World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/tortoise): Tortoise — wildlife guide.

## Where do tortoises live, and what do they eat?
Testudinidae occupy an unusually broad ecological range. Species are native to sub-Saharan Africa, the Mediterranean basin, the Middle East, South and Southeast Asia, and the Americas from the southern United States to northern Patagonia. Island giants have evolved independently on Madagascar, the Galapagos Archipelago, and Aldabra Atoll in the Indian Ocean. Across these regions, tortoises inhabit deserts, semi-arid scrublands, dry savannas, Mediterranean maquis, tropical dry forests, and even humid rainforest margins — anywhere that seasonal warmth can sustain an ectotherm. Burrowing is common in arid species: the desert tortoise of North America digs tunnels more than a metre deep to escape lethal summer heat and winter cold, spending up to 95 percent of its life underground. Diet is overwhelmingly herbivorous — grasses, leaves, flowers, cacti, and fallen fruit form the bulk of intake — though most species opportunistically consume fungi, carrion, or invertebrates to supplement minerals. The giant tortoises of the Galapagos act as ecosystem engineers, dispersing seeds of large-fruited plants across islands and grazing vegetation in patterns that maintain open habitat for other species. Water is extracted chiefly from food, and some arid-adapted tortoises can store water in an accessory bladder beneath the shell.

## How do tortoises reproduce, and why does that make conservation harder?
Tortoise reproduction is built for longevity, not speed — a strategy that works well in stable environments but becomes a serious vulnerability when populations are driven down quickly. Sexual maturity is typically reached only after a decade or more of growth; in large species such as the Aldabra giant tortoise, females may not produce their first clutch until their late teens or twenties. Courtship involves males competing through shoving contests and ritual head-bobbing; in some species males possess a forwardly projecting gular scute — an extension of the lower shell — used as a weapon to flip rivals. Females excavate a flask-shaped nest with their hind feet, depositing between 1 and 30 eggs depending on species size, then abandon the nest entirely. Incubation takes 70 to 120 days at naturally fluctuating soil temperatures. Crucially, sex is not determined by genetics but by nest temperature — a phenomenon called temperature-dependent sex determination (TSD). Warmer nests produce more females; cooler nests more males. As average soil temperatures rise with climate change, researchers have documented skewing sex ratios in multiple species, including Galapagos giant tortoises, a demographic shift that can eventually limit reproduction even in populations that appear numerically stable. Hatchlings emerge with soft shells and face high predation from introduced mammals. Combined with the species' slow maturation, the loss of even a small number of breeding adults can push a local population below recovery threshold for decades.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/tortoise): Tortoise — wildlife guide.

## Why are so many tortoise species endangered?
A 2025 Nature Communications study found that 54 percent of all chelonian species now face extinction risk, and within Testudinidae the situation is even more severe: over 86 percent of species are threatened or already extinct, the highest average threat level of any turtle family. Several converging pressures explain this crisis. First, the illegal wildlife trade. Tortoises are captured en masse for the international pet market — rare island species can fetch thousands of dollars per individual as status symbols — and for food and traditional medicine, particularly across Asia. A 2023 anti-poaching operation in Madagascar rescued more than 3,200 critically endangered radiated, ploughshare, and spider tortoises that had been seized for export. Second, habitat destruction. Agricultural expansion, charcoal production, and urban development are eliminating the dry forests and savanna woodlands that many species depend on. Third, invasive species introduced by humans — rats, pigs, cats, and goats — prey on eggs and hatchlings or strip away the vegetation tortoises need to survive. Fourth, climate change threatens to feminise populations through TSD disruption and reduce the availability of food plants during increasingly intense droughts. The illegal pet trade and exploitation for food remain the largest direct drivers globally, with Asia identified as the epicentre of the extinction crisis — harbouring 32 of the 66 most critically threatened chelonian species.

## What conservation efforts are protecting tortoises, and can they recover?
The evidence from some of the most desperate cases shows that tortoises can recover — but only with sustained, well-resourced intervention. The Española giant tortoise of the Galapagos is the standout example: reduced to just 15 individuals in the 1960s, a captive breeding programme produced more than 2,000 offspring that were repatriated to the island. Today, over 3,000 Española tortoises breed naturally there. The Aldabra giant tortoise, once hunted to dangerously low numbers in the 19th century, rebounded to more than 100,000 individuals after harvesting was halted and the atoll was given protected status. Legal frameworks provide an essential foundation. All Testudinidae species are listed on CITES appendices — the most threatened on Appendix I (commercial trade banned), the remainder on Appendix II (requiring verified export permits). Targeted captive breeding centres, invasive predator eradication on island nesting sites, and community engagement with local populations near tortoise habitat have all demonstrated measurable impact. Genomic tools now allow conservationists to identify the island-of-origin of confiscated individuals and to detect surviving carriers of ancestral genetics in hybrid populations, enabling precise reintroduction planning. However, the sheer number of species in crisis, combined with the slow generational pace of tortoise recovery, means that preventing the initial collapse — through better trade enforcement and habitat protection — remains far more cost-effective than rescue after the fact.

## WARN work
WARN does not currently run field projects specifically for tortoises, as WARN's rescue and conservation partnerships are focused in its partner-network countries. This guide is offered as free educational content to support public awareness of one of the world's most threatened reptile groups. Understanding why ancient animals like the tortoise are vanishing — and what trade policies and habitat decisions drive that loss — matters everywhere, regardless of where on the globe the action is taken.

## Donation hook
Tortoises have survived for tens of millions of years — but they cannot outpace the modern threats of illegal trade and habitat loss without human intervention. Supporting WARN helps fund the habitat protection work that gives ancient animals like these a fighting chance.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/tortoise): Tortoise — wildlife guide.

## How long do tortoises live?
Lifespans vary considerably by species, but tortoises are among the longest-lived vertebrates on Earth. Most medium-sized species live between 50 and 100 years in the wild. Giant species — Aldabra and Galapagos tortoises — routinely exceed 100 years and credibly documented individuals have reached 150 years or more. Jonathan, a Seychelles giant tortoise living on the island of St. Helena, is believed to have hatched around 1832, which would make him roughly 193 years old in 2026 and the oldest known living land animal. Their exceptional longevity is linked to slow metabolisms, low oxidative stress, and a capacity for cellular repair that scientists are actively studying for insights into ageing.

## Can a tortoise come out of its shell?
No. A tortoise's shell is a permanent, living part of its body — not a detachable house. The carapace (upper shell) and plastron (lower shell) are formed from around 50 to 60 fused bones including modified ribs and vertebrae, all supplied with nerves and blood vessels. Tortoises can feel pressure on their shells and the shell can bleed if cracked. What they can do is retract their head, limbs, and tail inside the shell when threatened.

## What is the difference between a tortoise and a turtle?
All tortoises are turtles (order Testudines), but the term 'tortoise' specifically refers to members of the family Testudinidae — fully land-dwelling reptiles with high-domed shells, stumpy elephantine legs, and no webbing between the toes. Aquatic and semi-aquatic turtles have flatter shells and webbed or flippered feet adapted for swimming. In everyday British English, 'tortoise' means a land species while 'turtle' usually refers to sea turtles; in North American English the lines blur more.

## Why are tortoises so slow?
Tortoises' slow movement is a by-product of their anatomy and energy budget, not a flaw. Their heavy, domed shell and thick columnar legs are built for stability and load-bearing rather than speed. As ectotherms, they rely on ambient heat to fuel muscle activity, which limits burst performance. More importantly, their entire life strategy is built around conserving energy: a low metabolic rate allows them to survive on sparse vegetation, tolerate long dry seasons, and channel resources into longevity and shell maintenance rather than rapid locomotion.

## Are tortoises good pets?
Tortoises have complex welfare needs that make them challenging pets requiring serious long-term commitment. They can live 50 to 100-plus years, meaning they will outlive most owners. They need species-appropriate temperatures, UV-B lighting, correct humidity, varied plant-based diets, and adequate space to roam. Many species available in the pet trade were illegally wild-caught, contributing directly to population declines. Prospective keepers should research local laws, obtain only captive-bred animals from licensed breeders, and be prepared for a decades-long commitment.

## How many tortoise species are there?
Depending on the taxonomic authority, the family Testudinidae contains approximately 40 to 60 recognised living species across 11 to 16 genera. The number fluctuates as molecular studies reveal cryptic species or synonymise previously separate taxa. Well-known species include the Galapagos giant tortoise (Chelonoidis niger), the Aldabra giant tortoise (Aldabrachelys gigantea), the radiated tortoise (Astrochelys radiata), the Russian tortoise (Testudo horsfieldii), and the leopard tortoise (Stigmochelys pardalis).


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/gila-monster): Gila Monster — wildlife guide.

## One-line answer
The Gila monster is a heavy, slow-moving venomous lizard of the American Southwest, classified as Near Threatened by the IUCN due to habitat loss, road mortality, and climate-driven changes to its desert home.

## Introduction
The Gila monster (Heloderma suspectum) is the only venomous lizard native to the United States and one of only two venomous lizard genera on Earth. Heavy-bodied and slow-moving, it roams the Sonoran and Mojave desert scrub of the American Southwest and the Mexican state of Sonora, spending up to 98% of its life sheltering underground. Its striking beaded skin — a mosaic of black, orange, and pink osteoderms — is both armour and advertisement, warning predators of the potent venom delivered through grooved teeth in its lower jaw. Revered and feared in equal measure for centuries, the Gila monster has more recently earned scientific acclaim: a compound isolated from its venom became the basis for exenatide (Byetta), a landmark drug for treating type 2 diabetes. Despite this remarkable contribution to human medicine, the species is classified as Near Threatened on the IUCN Red List, with populations quietly declining under pressure from urban sprawl, road mortality, illegal collection, and a shifting monsoon climate.

## Takeaway
The Gila monster is the only venomous lizard native to the United States, delivering venom through grooved lower-jaw teeth rather than hollow fangs.

## Takeaway
It spends as much as 98% of its life underground or in sheltered retreats, emerging mainly in spring to forage and mate.

## Takeaway
A compound in its venom — exendin-4 — led directly to exenatide (Byetta), the first GLP-1 receptor agonist approved for type 2 diabetes in 2005.

## Takeaway
The species is IUCN Near Threatened (assessed 2007), with populations declining primarily due to urban development, agricultural expansion, road mortality, and illegal collection.

## Takeaway
Climate change is now an acute threat: delayed monsoon seasons — even by just two weeks — can push individuals beyond their approximately 80-day dehydration tolerance window, and drought years are linked to a 20–30% drop in juvenile survival.

## Takeaway
Both its range states (USA and Mexico) protect the Gila monster by law, and international trade is regulated under CITES Appendix II.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/gila-monster): Gila Monster — wildlife guide.

## What is a Gila Monster?
The Gila monster (Heloderma suspectum) is a large, heavily built lizard belonging to the ancient family Helodermatidae — a lineage whose fossil record extends back more than 98 million years to the Cretaceous period, making these lizards older than the mass-extinction event that ended the dinosaurs 66 million years ago. Adults typically measure 40–56 cm (16–22 in) in total length and weigh between 550 and 800 g (1.2–1.8 lb), making them among the heaviest lizards in North America. The species is instantly recognisable by its armour of rounded, bead-like scales — osteoderms, which contain small bones beneath the skin surface — arranged in vivid patterns of black and orange or pink. This pattern is not fixed: the two recognised subspecies differ visibly, with the Reticulate Gila monster (H. s. suspectum) showing a more mottled, network-like pattern across the Sonoran and Chihuahuan deserts, while the Banded Gila monster (H. s. cinctum) displays cleaner alternating bands across the back in the Mojave Desert and northwestern Arizona. The tail serves as a fat-storage organ, swelling during times of plenty and shrinking during drought or winter dormancy. Unlike venomous snakes, which inject toxin through hollow fangs, the Gila monster chews its prey, working venom along grooves in enlarged lower-jaw teeth via capillary action. The result can cause severe pain, a drop in blood pressure, and swelling in humans — though bites are rarely if ever fatal when appropriate care is received.

## Where does the Gila Monster live?
Gila monsters are endemic to the arid and semi-arid zones of the American Southwest and northwestern Mexico. Their core range covers western and southern Arizona and extends into southern Sonora, Mexico, with peripheral populations in extreme southeastern California, southern Nevada, southwestern Utah, and southwestern New Mexico. They are most abundant in the Sonoran Desert, particularly in mountain foothills dominated by saguaro cacti and palo verde trees, and in rocky desert scrub where boulders, crevices, and pack-rat middens provide shelter. They also occupy semi-desert grasslands and venture along desert washes that channel seasonal runoff into valley floors. The lizard is fossorial by nature, retreating underground for the majority of the year. Activity above ground peaks between late April and mid-June, when temperatures are warm but not yet lethal, with occasional nocturnal activity following summer monsoon thunderstorms. Individuals rely on a mosaic of shelter sites within a well-defined home range, which in males can cover up to 60 hectares (150 acres). One long-term study recorded Gila monsters spending the equivalent of fewer than three months per year above the surface, making them among the most reclusive large reptiles in North America.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/gila-monster): Gila Monster — wildlife guide.

## What does the Gila Monster eat — and how does its venom work?
Gila monsters are opportunistic carnivores that feed infrequently but consume large meals when prey is available. Their diet includes small mammals (young rabbits, mice, and ground squirrels), bird eggs, lizard eggs, snake eggs, turtle eggs, and occasionally nestling birds. Juveniles can consume food equivalent to 50% of their body weight in a single sitting; adults manage roughly 35%. This capacity to store energy in the tail means that three or four large meals can sustain an individual for an entire year — an extraordinary physiological adaptation to desert life where prey can be scarce and unpredictable. The Gila monster's venom is produced in modified salivary glands in the lower jaw and is not injected but rather chewed into wounds. The venom is not neurotoxic; it is dominated by kallikrein-like serine proteinases and phospholipase A2, which trigger the release of bradykinins that cause intense pain, hypotension, and oedema. Additional components include hyaluronidase and helodermin. Despite the venom's potency, Gila monsters rarely bite humans unprovoked; they are docile unless handled or cornered. Of far greater scientific interest is the peptide exendin-4, discovered in Gila monster venom in the 1990s. Exendin-4 shares roughly 53% structural similarity with human glucagon-like peptide-1 (GLP-1) and stimulates insulin release in a glucose-dependent manner. This discovery led directly to exenatide (brand name Byetta), approved by the US FDA in 2005 as the first GLP-1 receptor agonist for type 2 diabetes — a drug class that has since helped millions worldwide.

## Why is the Gila Monster Near Threatened?
The IUCN Red List assessed the Gila monster as Near Threatened in 2007, noting that the species is probably in significant decline — though at a rate likely below the 30% threshold over three generations that would trigger Vulnerable status. The assessment authors (Hammerson, Frost, and Gadsden) identified habitat loss from urban and agricultural development as the primary driver, affecting the bulk of the species' US range where desert cities have expanded dramatically since the mid-twentieth century. Road mortality represents the second most significant threat: Gila monsters move deliberately across the landscape during their spring active season and are poorly equipped to avoid vehicles. Illegal collection for the pet trade remains a persistent pressure despite strong legal protections in all US range states; the animals are charismatic and command high prices. Climate change is now widely recognised as an acute and escalating threat. Research documents that delayed monsoon onset — even a shift of just two weeks — can push individuals beyond the approximately 80-day dehydration tolerance window provided by their urinary bladder water reserves, while drought years correlate with a 20–30% drop in juvenile survival. Modelling studies project that suitable Gila monster habitat in the Mojave Desert will shrink significantly under higher-emissions scenarios through 2070–2100, with the range slowly shifting northward. Their slow reproductive rate — sexual maturity at 3–5 years, clutches of only 2–12 eggs, and an approximately 9-month incubation period — means populations recover slowly from any localised setback.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/gila-monster): Gila Monster — wildlife guide.

## How is the Gila Monster protected?
The Gila monster benefits from a robust but imperfect set of legal protections. In the United States, it is protected by state law in every state where it occurs: Arizona, Nevada, California, Utah, and New Mexico all prohibit take, possession, or harm without a special permit. At the federal level, the US Fish and Wildlife Service lists the Gila monster as a species of conservation concern, and the Banded subspecies (H. s. cinctum) has its own separate profile. In Mexico, the species is listed as Protected (Protección Especial) under the official wildlife standard NOM-059-SEMARNAT. Internationally, the Gila monster is listed on CITES Appendix II, meaning international commercial trade requires documentation to ensure it does not threaten wild populations. Conservation challenges persist nonetheless: enforcement in remote desert terrain is difficult, and legal loopholes in some jurisdictions have historically allowed captive-bred animals to mask wild-caught individuals in the trade. Ongoing research programmes — including long-term radio-telemetry studies tracking home range use, monsoon dependency, and body condition — continue to generate data that inform state-level management plans. Protected area coverage of the range is partial; much prime habitat in Arizona's Sonoran Desert falls within private ranchland or unprotected public land, making voluntary stewardship and landowner education important components of any meaningful conservation strategy.

## WARN work
WARN does not currently run field projects for the Gila monster — its range lies entirely within the United States and Mexico, outside the countries where WARN's partners work in-network countries. This guide is offered as free educational content, because public understanding of threatened species everywhere is the foundation of a culture that values wildlife. When people learn why a desert lizard matters — medically, ecologically, and in its own right — that awareness strengthens the case for conservation investment worldwide.

## Donation hook
The Gila monster is a reminder that the natural world holds solutions to human diseases we have not yet imagined — but those solutions depend on wild populations surviving long enough to be studied. Supporting WARN helps fund the kind of habitat protection and wildlife education work that keeps ecosystems intact, wherever threatened animals live.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/gila-monster): Gila Monster — wildlife guide.

## Is the Gila monster dangerous to humans?
A Gila monster bite is extremely painful and can cause swelling, nausea, low blood pressure, and weakness, but there are no reliably documented human fatalities from a Gila monster bite in modern medical records. Bites almost always occur when humans attempt to handle or provoke the animal. The lizard is slow-moving, non-aggressive, and will typically attempt to retreat before biting.

## How did a Gila monster venom compound lead to a diabetes drug?
Scientists discovered that Gila monster venom contains a peptide called exendin-4, which shares about 53% structural similarity with the human hormone GLP-1 and stimulates insulin release in a glucose-dependent manner. A synthetic version — exenatide, sold as Byetta — was approved by the US FDA in 2005 as the first GLP-1 receptor agonist for type 2 diabetes, a drug class now used by tens of millions of people globally.

## How long can a Gila monster go without eating?
Gila monsters can survive for many months — potentially over a year — without eating, drawing on fat reserves stored in their thick tails. In the wild, they typically consume only a few large meals per year during their brief active season in spring. Adults can consume food equivalent to roughly 35% of their body weight in a single feeding.

## Why does the Gila monster spend so much time underground?
Spending up to 98% of their lives underground or in sheltered retreats is a key survival strategy in the extreme desert environment. Underground temperatures remain far more stable than the lethal surface heat of a Sonoran summer, and sheltering minimises water loss. Gila monsters also store water in their urinary bladder, which can provide roughly 80 days of buffer against dehydration before they must drink. They emerge mainly in the cooler mornings of spring and early summer, retreating again as temperatures climb.

## Are Gila monsters legal to keep as pets?
In the United States, Gila monsters are protected by law in every state they inhabit — Arizona, Nevada, California, Utah, and New Mexico — and possession without a permit is illegal. International trade is regulated under CITES Appendix II. Some jurisdictions allow captive-bred animals with proper permits, but the legality is complex and varies by location. Wild collection is universally prohibited.

## How is climate change affecting Gila monsters?
Climate change is disrupting the timing and intensity of the summer monsoon rains that Gila monsters depend on for hydration and food availability. Research indicates that a monsoon delay of as little as two weeks could push individuals past their approximate 80-day dehydration tolerance threshold. Drought years are also linked to a 20–30% reduction in juvenile survival. Habitat-suitability models predict that the Mojave Desert population — the northernmost part of the range — faces the sharpest projected habitat loss by the end of this century.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/black-mamba): Black Mamba — wildlife guide.

## One-line answer
The black mamba (Dendroaspis polylepis) is the longest venomous snake in Africa, capable of speeds up to 19 km/h, with a potent neurotoxic venom that is nearly 100% fatal if untreated — yet it is listed as Least Concern by the IUCN and remains ecologically important as a predator of rodents and small mammals across sub-Saharan Africa.

## Introduction
The black mamba (Dendroaspis polylepis) is Africa's longest venomous snake and one of the most mythologised reptiles on Earth. Despite its fearsome reputation, this sleek elapid is not black at all — its common name refers to the inky-dark interior of its open mouth, a threat display it uses before striking. Adults typically reach 2–2.5 metres, with exceptional individuals recorded at up to 4.3 metres. Found across the savannas, rocky hillsides, and woodland edges of sub-Saharan Africa, the black mamba is a fast-moving, predominantly diurnal predator that helps control rodent populations across some of the continent's most biodiverse ecosystems. Understanding this snake — its biology, its venom, and its true temperament — is the first step toward human-wildlife coexistence in the regions where it lives.

## Takeaway
The black mamba is named for the dark interior of its open mouth, not its skin colour — its body is typically olive, grey, or brownish.

## Takeaway
It is the world's fastest land snake, capable of reaching 16–19 km/h according to Guinness World Records, though it uses speed primarily to flee rather than to pursue prey.

## Takeaway
Venom is predominantly neurotoxic, containing dendrotoxins and alpha-neurotoxins; without prompt antivenom treatment, a bite is considered almost universally fatal.

## Takeaway
Black mambas are shy and prefer to escape confrontation — the vast majority of bites occur when a snake is cornered, handled, or accidentally stepped on.

## Takeaway
The species plays a critical ecological role as a top predator controlling rodent and small-mammal populations throughout sub-Saharan savannas.

## Takeaway
Snakebite is a WHO-recognised Neglected Tropical Disease; antivenom shortages in sub-Saharan Africa mean that even survivable bites regularly cause preventable deaths.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/black-mamba): Black Mamba — wildlife guide.

## What is the black mamba and how is it identified?
The black mamba (Dendroaspis polylepis) is a large, fast-moving, highly venomous snake belonging to the family Elapidae — the same group that includes cobras, mambas, and coral snakes. Its scientific name translates loosely to 'many-scaled tree asp', though adult black mambas are largely terrestrial. The common name is genuinely misleading: the snake's dorsal scales range from uniform olive and grey to brownish-khaki, occasionally with faint blue-grey iridescence. The characteristic 'blackness' is exclusively the dark blue-black lining of the open mouth — a dramatic gape used as a warning display when the snake feels threatened.

Adults average 2–2.5 metres in length, but specimens up to 4.3 metres have been recorded, making it the longest venomous snake native to Africa and the second longest in the world after the king cobra. The body is slender and slightly compressed, with a distinctive coffin-shaped head, smooth scales, and alert, round, medium-sized eyes. Black mambas lack a hood and do not rear up dramatically at rest; instead, they hold the front third of the body erect when threatened, mouth agape, before either fleeing or striking. The tail is long and tapers to a fine point. Juveniles are paler than adults and often have a greenish hue that darkens with age.

## Where do black mambas live and what is their habitat?
Black mambas have one of the widest distributions of any African venomous snake, inhabiting a large arc of sub-Saharan Africa. Their confirmed range runs from Burkina Faso in West Africa through the horn of Africa — including Ethiopia, Somalia, and Kenya — and southward through Tanzania, Mozambique, Zimbabwe, Botswana, and into South Africa and Namibia. They are most abundant in southern and eastern Africa; presence further west, including unconfirmed historical sightings from Senegal, remains disputed.

Habitat preferences are varied but the species strongly favours open or semi-open environments: dry savanna, rocky hillsides, woodland edges, dense scrub, and bushy vegetation. The snake is largely terrestrial but is an adept climber and will ascend rocky outcrops, low trees, and tall shrubs in pursuit of prey or when seeking shelter. Unlike the more arboreal green mambas, the black mamba typically hunts on the ground.

Black mambas are strongly site-faithful: individuals return repeatedly to the same shelter — a rock crevice, a termite mound, or a hollow log — and may occupy the same retreat for years. Home ranges vary with habitat quality. In agricultural landscapes and areas of expanding human settlement, preferred habitat is being steadily fragmented, forcing snakes into contact with people more often. Elevation range extends from sea level to over 1,000 metres in suitable habitat across East Africa.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/black-mamba): Black Mamba — wildlife guide.

## How dangerous is the black mamba's venom?
The black mamba's venom is among the most complex and rapidly acting of any snake. It is predominantly neurotoxic, composed of multiple components — principally dendrotoxins (which block voltage-gated potassium channels, causing sustained neuronal firing and involuntary muscle contractions) and alpha-neurotoxins (which block neuromuscular junctions, producing flaccid paralysis). A single defensive bite can deliver 100–120 mg of venom (dry weight), with very large individuals capable of delivering substantially more across repeated strikes.

Symptoms onset rapidly: tingling, sweating, hypersalivation, and abdominal pain can appear within ten minutes of a significant bite. Neurological collapse — confusion, ptosis, difficulty swallowing, and progressive respiratory paralysis — typically follows within 30–60 minutes. Without antivenom or mechanical ventilation, death from respiratory failure can occur in as few as 7 to 15 hours. Untreated black mamba envenomation is considered to carry a near-100% case fatality rate.

Antivenom is effective if given promptly and in adequate quantities, but in many rural areas of sub-Saharan Africa it remains dangerously scarce. The WHO designated snakebite envenoming a Neglected Tropical Disease in 2017 and set a target of halving global snakebite deaths and serious injuries by 2030. In sub-Saharan Africa alone, estimates suggest approximately 500,000 snakebite envenomings occur annually, resulting in around 20,000–32,000 deaths. The black mamba, as one of the continent's most medically significant species, sits at the heart of this public-health challenge.

## What does the black mamba eat and how does it hunt?
The black mamba is a generalist carnivore and an efficient sit-and-ambush predator, though it will actively forage when prey density is low. Its diet consists primarily of warm-blooded vertebrates — small mammals including rodents, shrews, bats, and rock hyraxes, plus birds such as nestlings and fledglings raided from low vegetation. Hatchlings and juveniles begin with smaller lizards and small rodents, shifting toward larger prey as they grow.

The species is predominantly diurnal, hunting during daylight hours and returning to its shelter before nightfall. When prey is detected by its acute vision and chemosensory (Jacobson's organ) system, the mamba delivers a rapid, pre-emptive strike — often multiple strikes in quick succession — injecting venom before retreating. The fast-acting neurotoxin incapacitates prey within seconds, allowing the snake to track and swallow the animal headfirst without a prolonged struggle.

The black mamba's ecological role as a rodent predator is significant. In agricultural zones across southern and eastern Africa, mambas help limit populations of crop-raiding and disease-carrying rodents. Removing them from an ecosystem — as frequently occurs through persecution — can lead to rodent population spikes, with knock-on effects for both crops and zoonotic disease transmission. This makes the black mamba, despite its fearsome reputation, an ecologically valuable member of savanna and woodland communities.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/black-mamba): Black Mamba — wildlife guide.

## What are the main threats facing the black mamba today?
The IUCN classifies the black mamba as Least Concern, reflecting its wide distribution and stable population trend across most of sub-Saharan Africa. However, localised pressures are eroding populations in certain parts of its range and warrant ongoing attention.

Habitat loss and fragmentation rank as the primary structural threat. Expanding agricultural land, urban growth, and road networks in southern and eastern Africa are steadily reducing the areas of intact savanna and rocky scrub that black mambas depend on. Habitat fragmentation also increases human-snake contact, which in turn elevates persecution risk.

Fear-driven killing is the most direct human threat. Black mambas near homesteads or farmland are routinely killed on sight, often by communities with good reason to be cautious about their venom but limited access to information about the snake's behaviour. Education programmes that teach people how to identify mambas, avoid bites, and respond appropriately to encounters reduce both human fatalities and retaliatory killings.

Road mortality, incidental capture in snare-based bushmeat hunting, and very limited use in traditional medicine represent additional, more minor pressures. The species is not currently the subject of significant commercial trade, and no CITES listing applies to it. The greatest near-term conservation concern is ensuring that antivenom access and snakebite education keep pace with human population growth in mamba-range countries.

## WARN work
WARN does not currently run field projects for the black mamba, and this guide is offered as free educational content to support broader wildlife literacy. Understanding Africa's most misunderstood snake — and reducing fear-driven persecution through knowledge — is a conservation goal that benefits entire ecosystems. WARN's active rescue and conservation partnerships focus on its partner-network countries, but the organisation believes that public education about any threatened or ecologically critical species makes a meaningful difference wherever people care enough to read about them.

## Donation hook
Wild Africa's ecosystems depend on predators like the black mamba to keep rodent populations in check — yet fear and misinformation mean thousands are killed every year. Supporting WARN helps fund the kind of wildlife education that turns fear into understanding, reducing persecution of misunderstood species the world over.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/black-mamba): Black Mamba — wildlife guide.

## Is the black mamba really black?
No. The black mamba's body is olive, grey, or brownish — not black. The name comes from the deep blue-black colour inside its mouth, which it displays open-mouthed as a warning when it feels threatened. This coffin-shaped gape is one of the snake's most distinctive identifying features.

## How fast can a black mamba move?
The black mamba is the fastest land snake in the world. According to Guinness World Records, it can reach speeds of 16–19 km/h (10–12 mph) in short bursts over level ground. It uses this speed primarily to escape predators or move between refuges, not to chase prey. Most people can outrun a black mamba on open ground.

## What should you do if you are bitten by a black mamba?
A black mamba bite is a medical emergency. Keep the victim calm and still to slow venom spread, immobilise the bitten limb below heart level, and get to a hospital with antivenom as fast as possible. Do not cut, suck, tourniquet, or apply electric shock — these measures are ineffective and cause harm. Time to antivenom is the single most important factor in survival.

## Are black mambas aggressive toward humans?
Black mambas are not naturally aggressive toward humans and prefer flight over confrontation. Nearly all documented bites occur when a snake is cornered, accidentally stepped on, or deliberately handled. Given a clear escape route, a black mamba will almost always retreat rather than strike. The widespread perception of unprovoked aggression is a myth that contributes to unnecessary killings.

## What do black mambas eat?
Black mambas are carnivores that prey mainly on small mammals — rodents, hyraxes, shrews, and bats — as well as birds, particularly nestlings and fledglings. They are primarily diurnal hunters that use both ambush and active foraging strategies, detecting prey through vision and chemosensory cues via their forked tongue and Jacobson's organ.

## Is the black mamba endangered?
The black mamba is classified as Least Concern on the IUCN Red List, with a stable population across its broad sub-Saharan range. It is not endangered as a species. However, localised populations face pressure from habitat loss, road mortality, and fear-driven persecution, and the species is not protected by any CITES appendix listing, meaning commercial trade is theoretically unrestricted.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/piranha): Piranha — wildlife guide.

## One-line answer
The piranha is a freshwater fish native to South American river systems, most abundant in the Amazon basin, where it serves as both predator and scavenger; the red-bellied piranha (Pygocentrus nattereri) is rated Least Concern by the IUCN but faces growing pressure from deforestation, dam construction, and mercury pollution across its range.

## Introduction
Few animals carry a more distorted reputation than the piranha. Immortalised in horror films and sensational travel writing — most notoriously by Theodore Roosevelt after his 1914 Amazon expedition — piranhas are widely imagined as frenzied, unstoppable predators capable of reducing a cow to a skeleton in seconds. The reality is far more nuanced and, frankly, more fascinating. Of the roughly 30 to 60 recognised piranha species across South America's great river basins, the red-bellied piranha (Pygocentrus nattereri) is the most studied and the most feared, yet research consistently shows it schools primarily for self-defence, subsists heavily on seeds and fin-fragments, and plays an irreplaceable ecological role as scavenger and nutrient recycler in the Amazon, Orinoco, Paraguay–Paraná, and São Francisco river systems.

## Takeaway
Piranhas school primarily as a defence against their own predators — caimans, river dolphins, and fish-eating birds — not to hunt in cooperative packs.

## Takeaway
The red-bellied piranha (Pygocentrus nattereri) is rated Least Concern by the IUCN (assessed December 2020) and is not listed on any CITES appendix.

## Takeaway
Documented fatal attacks on humans are exceedingly rare; of 711 reported incidents, over 82% were classified as mild, single-bite defensive responses.

## Takeaway
Piranhas are ecological omnivores: fruits, seeds, insects, fin-clips, and carrion all feature in their diet, making them important seed dispersers and nutrient recyclers.

## Takeaway
Deforestation, large hydroelectric dams, agricultural runoff, and illegal gold mining (which deposits mercury into river systems) are the principal long-term threats to piranha habitat.

## Takeaway
Amazon fish including carnivorous piranhas can bioaccumulate mercury at concentrations exceeding Brazil's legal limits for human consumption, posing risks to riverside communities.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/piranha): Piranha — wildlife guide.

## What is a piranha and how is it classified?
Piranhas are freshwater ray-finned fish belonging to the subfamily Serrasalminae within the family Serrasalmidae, order Characiformes — the same broad group that includes tetras and characins. The genus Pygocentrus contains the three species most associated with the "dangerous piranha" label: P. nattereri (red-bellied piranha), P. piraya (San Francisco piranha), and P. cariba (black-spot piranha). Serrasalmus and Pristobrycon add dozens of further species, many of which are largely herbivorous or piscivorous rather than the generalised omnivores of popular imagination. The total number of recognised piranha species is debated — estimates range from around 30 to more than 60, depending on taxonomic authority — reflecting the group's explosive evolutionary diversification across South American waterways. What unites them is a distinctive body plan: laterally compressed, deep-bodied, and equipped with a single row of interlocking, blade-like teeth in each jaw. Unlike sharks, which replace teeth individually throughout life, piranhas shed and replace teeth in quarter-jaw blocks, maintaining a continuous cutting edge. The lower jaw is heavily muscled and slightly protruding, giving the fish its characteristic blunt-snouted profile.

## Where do piranhas live and what habitats do they prefer?
Piranhas are native exclusively to South America, with the red-bellied piranha occupying the broadest range of all piranha species. Its territory spans the Amazon basin in Brazil, Bolivia, Colombia, Ecuador, and Peru; the Orinoco system in Venezuela and Colombia; the Guiana river systems; and the Paraguay–Paraná drainage extending into Argentina and Paraguay. This places the species firmly within WARN's in-network conservation focus countries of Brazil and Colombia, where Amazonian and Orinocan river systems support some of the world's most biodiverse freshwater environments.

Piranhas are habitat generalists within tropical fresh water. They thrive in fast-flowing river channels, flooded varzea forests during the wet season, shallow oxbow lakes, and murky blackwater tributaries. Water temperature between 24 °C and 28 °C is optimal. Seasonal flooding is ecologically critical: when the Amazon expands to cover millions of hectares of rainforest between December and May, piranhas move into inundated woodland to feed on fallen fruits and invertebrates, performing an underappreciated role as seed dispersers. As waters recede in the dry season, fish become concentrated in shrinking pools, food competition intensifies, and piranhas — stressed and crowded — become genuinely more reactive, which accounts for the higher incidence of defensive bites reported during low-water months.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/piranha): Piranha — wildlife guide.

## What do piranhas eat, and are they really dangerous to humans?
The piranha's diet is far more varied than Hollywood suggests. Studies of stomach contents from wild-caught red-bellied piranhas reveal fish flesh, fin fragments nipped from living prey, insects, crustaceans, aquatic invertebrates, seeds, and ripe fruits. At certain times of year, plant material dominates the diet. This broad omnivory means piranhas function simultaneously as apex micropredators, scavengers, and seed dispersers — a combination that makes them disproportionately important for ecosystem function.

The piranha's teeth are phenomenally efficient tools. Adult P. nattereri produce bite forces exceeding 84 newtons, and the interlocking enamel blades slice rather than crush, allowing rapid processing of tough prey. Even so, the animals direct this weaponry at humans only under specific conditions. A 2025 peer-reviewed study published in a Brazilian medical journal reviewed 711 reported piranha–human incidents: more than 82% were classified as mild, involving a single defensive bite — typically to a finger or toe — associated with a male fish guarding its nest. Documented human fatalities attributed solely to piranha attack are essentially absent from the scientific record; most fatal drowning incidents in piranha-inhabited waters appear to involve scavenging on individuals already deceased.

Piranhas are themselves hunted by caimans, giant otters, river dolphins, and large wading birds. Their schooling behaviour, once interpreted as cooperative predatory strategy, is now understood by researchers primarily as an anti-predator response: individuals in larger shoals recover baseline physiological stress markers faster after a simulated predator encounter than those in small groups.

## What are the main threats to piranhas and their Amazon habitat?
Despite the red-bellied piranha's Least Concern IUCN status, the Amazon basin that sustains it is under severe and accelerating pressure. The primary threats operate at the ecosystem level rather than targeting piranhas directly, but their cumulative impact on freshwater fish communities is profound.

Deforestation drives siltation, raises water temperatures, and destroys the riparian and flooded forest habitats that piranhas rely on for shelter and food during the wet season. Agricultural conversion — particularly for soy cultivation and cattle ranching — is the dominant driver of Amazon deforestation. Hydroelectric dam construction compounds these effects: large dams fragment river corridors, block the seasonal flood pulses that trigger piranha spawning, and reduce downstream delivery of sediments and nutrients by as much as 64%, according to modelling of six proposed Andean dam projects. This nutrient impoverishment ripples up the food web, reducing the fish prey populations that piranhas depend on.

Illegal gold mining (garimpo) releases elemental mercury into river systems, where it methylates and bioaccumulates through aquatic food chains. A 2026 study found that carnivorous fish in the Amazon — including piranhas — contained mercury concentrations exceeding Brazil's legal limits for human consumption, threatening both the fish community and the riverine communities who rely on them as a protein source. Overfishing exerts additional pressure, though piranhas are more often caught as bycatch than as targeted species. Together, these threats create a slowly deteriorating baseline that even abundant, resilient species such as P. nattereri cannot indefinitely absorb.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/piranha): Piranha — wildlife guide.

## How do piranhas reproduce and raise their young?
Red-bellied piranhas typically spawn during the South American wet season, when rising floodwaters signal optimal conditions. Courtship involves males and females circling one another in an extended display before the male excavates a shallow, bowl-shaped nest in sandy or silty substrate. The female deposits between 4,000 and 6,000 eggs into this prepared pit, which the male fertilises externally before taking up guard duty. Egg incubation lasts approximately two to three days under warm Amazonian water temperatures, and the larvae become free-swimming within a week of hatching.

Parental care is notably more active in piranhas than in many teleost fish: the male guards the nest aggressively against intruders — including wading humans — which is the most common trigger for defensive bites documented in the scientific literature. Once the fry disperse, they adopt a schooling lifestyle from the outset, finding safety in numbers against the diverse array of piscivores that target juvenile piranhas.

Growth is relatively rapid; red-bellied piranhas reach sexual maturity within their first year in warm, food-rich conditions. Adults commonly reach 25 to 35 centimetres in length and up to 3.9 kilograms in weight, though specimens approaching 50 centimetres have been recorded. Maximum lifespan in the wild is estimated at up to 25 years, though average survival is considerably shorter given predation and environmental pressures. In well-maintained captive settings, individuals routinely live 15 to 20 years.

## WARN work
WARN runs active rescue and conservation programmes in Brazil and Colombia — two countries at the heart of the piranha's Amazonian and Orinocan range. While WARN's focus in these countries centres on terrestrial and semi-aquatic wildlife rescue rather than piranha-specific projects, the health of the Amazon's freshwater ecosystems is inseparable from the welfare of all wildlife living in and around them. Education about species like the piranha — demystifying their true role and highlighting the real threats to their habitat — is a cornerstone of how informed public support translates into protection for the broader Amazon biome.

## Donation hook
Healthy piranha populations are a barometer of healthy Amazonian rivers. When mercury from illegal mining or sediment from deforestation degrades those waters, the entire freshwater food web — from the smallest invertebrate to the largest river dolphin — suffers. Supporting WARN's work in Brazil and Colombia helps protect the river ecosystems that species like the piranha, and the communities who depend on them, call home.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/piranha): Piranha — wildlife guide.

## Can piranhas really skeletonise a human or large animal in minutes?
No. The image of piranhas reducing a body to bones in moments is a persistent myth amplified by staged demonstrations — Theodore Roosevelt famously witnessed a frenzied attack on a cow that had been kept hungry and then deliberately introduced to a confined shoal. Under natural conditions, piranha feeding frenzies of that intensity are extremely unusual. Most wild encounters with humans result in a single defensive bite, and documented human fatalities attributed solely to piranha attack are absent from peer-reviewed scientific records.

## How many species of piranha exist?
Taxonomists recognise between approximately 30 and 60 piranha species, depending on the classification system used, all within the subfamily Serrasalminae of the family Serrasalmidae. The three Pygocentrus species — P. nattereri (red-bellied), P. piraya (San Francisco), and P. cariba (black-spot) — are the most studied and most associated with aggressive behaviour. Many other piranha species are largely herbivorous or feed primarily on fin tissue rather than flesh.

## Are piranhas endangered?
The red-bellied piranha (Pygocentrus nattereri) is assessed as Least Concern on the IUCN Red List (last evaluated December 2020), meaning it is not currently considered threatened with extinction. No piranha species is listed on any CITES appendix. However, growing pressures on the Amazon basin — deforestation, hydroelectric dams, mercury pollution from illegal gold mining, and agricultural runoff — are degrading the freshwater habitats that sustain piranha populations over the long term.

## Why do piranhas school together?
Research published in the journal Biology Letters demonstrated that piranhas school primarily as a defence against their own predators, which include caimans, giant otters, Amazon river dolphins, and large birds such as herons and cormorants. Individuals in larger shoals showed lower physiological stress responses after a simulated predator attack than those in small groups, supporting the hypothesis that schooling is an anti-predator adaptation rather than a cooperative hunting strategy.

## Do piranhas help the Amazon ecosystem?
Yes, significantly. Piranhas act as scavengers, removing carcasses and recycling nutrients back into the water column. As seasonal omnivores, they consume ripe fruits and seeds during the flooded forest season and void viable seeds downstream, contributing to plant dispersal and forest regeneration. By cropping fin tissue from larger fish they also regulate populations of prey species. This multi-functional ecological role makes them important indicators of river health.

## Is it safe to swim in the Amazon where piranhas live?
Local Amazonian communities routinely bathe and fish in piranha-inhabited waters. Risk is low under normal conditions but increases during the dry season when falling water levels concentrate fish in smaller pools, reduce food availability, and heighten stress-related reactivity. Open wounds, struggling fish on lines or in nets, and disturbance near nesting males are the most consistent risk factors identified in medical literature. The vast majority of reported incidents involve a single bite to a finger or toe rather than a sustained attack.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/sturgeon): Sturgeon — wildlife guide.

## One-line answer
Sturgeons (family Acipenseridae) are ancient, armoured freshwater and anadromous fish of the Northern Hemisphere; they are the most endangered group of animals on Earth, with 17 of 26 surviving species listed as Critically Endangered on the IUCN Red List, driven to the brink by poaching for caviar, dams that block migration, and widespread habitat loss.

## Introduction
Sturgeons are among the oldest vertebrates still swimming in our rivers and seas. Members of the family Acipenseridae, these armoured giants first appeared some 200–250 million years ago, surviving the mass extinction that ended the dinosaurs almost unchanged. Twenty-six species in the broader order Acipenseriformes survive today — one, the Chinese paddlefish, was declared extinct in 2022 — ranging from the diminutive sterlet (up to ~16 kg) to the colossal beluga, which can exceed 1,500 kg and live for over a century. Found across the rivers, lakes and coastal seas of the Northern Hemisphere, sturgeons are anadromous travellers, fattening in deep estuaries and open seas before ascending freshwater rivers to spawn. Yet despite their ancient resilience, sturgeons now carry the grim distinction of being the most threatened group of species on the planet, with every remaining species threatened by poaching, pollution, dams and climate change.

## Takeaway
Sturgeons have existed for over 200 million years, yet more than half of all surviving species could vanish within our lifetime.

## Takeaway
Wild populations have crashed by an estimated 94% since 1970, the most catastrophic decline of any vertebrate group.

## Takeaway
The primary driver is illegal poaching for caviar, with beluga caviar fetching over $1,500 per pound on luxury markets — wild black-market prices run far higher.

## Takeaway
Hydropower dams on rivers like the Danube and Volga block spawning migrations that can exceed 1,700 km, cutting fish off from the gravel beds they need to reproduce.

## Takeaway
Hatchery restocking programmes on the Danube are releasing hundreds of thousands of fingerlings annually, but natural reproduction remains critically rare.

## Takeaway
International trade in all sturgeon species is regulated under CITES, with two species — the Baltic sturgeon and the shortnose sturgeon — prohibited from commercial trade under Appendix I.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/sturgeon): Sturgeon — wildlife guide.

## What is a sturgeon?
Sturgeons belong to the order Acipenseriformes and the family Acipenseridae, a lineage so ancient it predates the earliest flowering plants. Their body plan is strikingly primitive: a mostly cartilaginous skeleton, five rows of bony plates called scutes running the length of the body, a heterocercal tail in which the upper lobe is longer than the lower, and a flattened rostrum tipped with four sensitive barbels that trail just ahead of a toothless, protrusible mouth. That mouth works like a vacuum nozzle, hovering over riverbeds to suck up insect larvae, worms, crustaceans and small molluscs. Sturgeon range enormously in size. The sterlet (Acipenser ruthenus), the smallest of all sturgeon species, reaches a maximum of around 1.2 m and roughly 16 kg, while the beluga (Huso huso) is the world's largest freshwater fish and the third-most-massive living bony fish by weight, historically recorded at more than 7 m long and 1,571 kg. Lifespans are equally extraordinary: female lake sturgeon have been confirmed at 150 years of age, and beluga are known to exceed a century. Late sexual maturity — females may not spawn until they are 20–25 years old — makes each breeding adult irreplaceable, and population recovery from over-harvest agonisingly slow.

## Where do sturgeon live?
The 26 surviving sturgeon and paddlefish species in the order Acipenseriformes divide their lives between saltwater feeding grounds and freshwater spawning rivers across the Northern Hemisphere. The greatest diversity sits in the Caspian and Black Sea basins, where beluga, Russian, Persian, stellate and other sturgeons once ascended the Volga, Ural, Don, Danube and Kuban rivers in colossal seasonal runs. The Amur River along the Russia–China border hosts Kaluga and Amur sturgeons, while North America supports white, lake, Atlantic, shortnose, green and gulf sturgeons across its major river systems from the St Lawrence to the Sacramento. European rivers historically carried eight species as far inland as Germany, though the Iron Gate dams on the Danube now cap upstream migration at roughly 860 km from the river mouth, confining fish to the lower stretch and cutting them off from historic breeding sites in Hungary, Austria and Germany. Most sturgeon are anadromous, spending years at sea before returning to the very river stretch where they hatched, guided by olfactory memory. Spawning habitat is highly specific: sturgeons need fast, oxygen-rich current over clean gravel or cobble substrate at precise temperature windows. Siltation from land runoff, dredging and mineral extraction can render entire river reaches functionally sterile for reproduction.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/sturgeon): Sturgeon — wildlife guide.

## Why are sturgeon critically endangered?
The IUCN Red List assessment published in July 2022 confirmed that sturgeons are the most threatened group of species ever evaluated: 17 of 26 surviving species are Critically Endangered, one — the Yangtze sturgeon — is Extinct in the Wild, and the Chinese paddlefish was formally declared extinct. Global wild populations have collapsed by an estimated 94% since 1970. The drivers are mutually reinforcing and severe. Poaching and illegal caviar trade sit at the centre of the crisis. Beluga caviar can retail for over $1,500 per pound — and black-market prices run far higher — making a gravid female worth tens of thousands of dollars. From 2016 to 2022, 337 sturgeon wildlife crimes and nearly 1,000 seizures were recorded across the Lower Danube region alone. CITES regulates international trade in all species, with Baltic and shortnose sturgeons listed under Appendix I (commercial trade banned) and all others under Appendix II. But enforcement remains inconsistent: surveys in Bulgaria, Romania, Serbia and Ukraine found roughly one third of sturgeon products on sale were illegal. Hydropower dams compound the damage by cutting off migration routes; the Iron Gate complex on the Danube alone wiped out access to the upstream spawning beds that once sustained six species. Sand and gravel mining, agricultural runoff, river channelisation and warming water temperatures round out a pressures profile that offers sturgeons almost no refuge.

## How do sturgeon reproduce and how long do they live?
Sturgeon reproduction is an event of biological extravagance and exquisite timing. Adults are triggered to migrate by rising spring water temperatures and flows, sometimes travelling more than 1,000 km to reach natal gravel beds. A large female beluga may carry 20–25% of her body weight in eggs — a single fish can yield 100 kg of roe — and she releases them across clean substrate where males fertilise them externally. Larvae hatch within a few days, are carried downstream to slower waters, and begin the decades-long journey to adulthood. The slow pace of maturation is the family's greatest vulnerability. Russian sturgeons in the Caspian do not reach sexual maturity until 10–16 years; beluga females may wait 20–25 years for their first spawn, and thereafter they do not breed every year. Lake sturgeon females in North America have been confirmed at 150 years of age. This life history strategy evolved in a world of stable, productive river systems where a fish could afford to grow slowly and breed repeatedly over a long lifetime. In a world of nets, dams and polluted rivers, it becomes a slow-motion path to local extinction, because the loss of a single adult female may represent two decades of vanished reproductive potential.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/sturgeon): Sturgeon — wildlife guide.

## What conservation efforts are underway to save sturgeon?
Scientists and river managers have responded to the sturgeon crisis with a suite of interventions, though experts caution that none substitutes for addressing root causes. Hatchery programmes are the most widespread tool: in the Austrian Danube, 35,380 sterlets were released in 2024 alone, and a floating hatchery station in Vienna is now producing fish for the EU-funded LIFE-Boat4Sturgeon project, which runs to 2030 and targets four Danube species. In June 2025, over 1,500 young Russian sturgeons and 15 larger beluga were released into the Danube near Fetesti, Romania, in one of the most recent stocking efforts. Romania indefinitely banned wild-sturgeon fishing and trade in 2021 — a milestone legal protection on one of the last rivers with reproducing wild populations. Monitoring in 2024 detected juvenile sterlets in Lower Austria for the first time in over 40 years, raising cautious optimism that natural reproduction may be resuming. In a parallel breakthrough in June 2025, researchers witnessed the first confirmed natural spawning of the Yangtze sturgeon in the wild in decades, in a relatively undammed tributary of the upper Yangtze. Campaigns to restore fish-passage around major dams, reduce sand-dredging, and phase out illegal caviar supply chains are also underway. Internationally, IUCN's Sturgeon Specialist Group coordinates research and policy, while CITES trade reporting requirements provide a mechanism — if imperfectly enforced — to police the global caviar market.

## WARN work
WARN does not currently run projects for sturgeon — their Northern Hemisphere river and sea range lies outside WARN's operational countries — and this guide is offered as free educational content. Understanding why an ancient lineage tips toward extinction, and how poaching for a luxury product can undo 200 million years of evolution, strengthens the public case for wildlife protection everywhere.

## Donation hook
Every wildlife habitat protected — whether a river corridor, wetland or coastal estuary — is a lifeline for species fighting extinction. Supporting WARN's habitat protection work keeps ecosystems intact for the animals that depend on them most.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/sturgeon): Sturgeon — wildlife guide.

## What is the most endangered sturgeon species?
Multiple sturgeon species share Critically Endangered status, but the beluga (Huso huso) and Russian sturgeon (Acipenser gueldenstaedtii) are among the most iconic and deeply threatened. The Chinese paddlefish (Psephurus gladius) was declared extinct following the 2022 IUCN reassessment, and the Yangtze sturgeon (Acipenser dabryanus) is listed as Extinct in the Wild — meaning it persists mainly through captive breeding. In a significant development in June 2025, scientists witnessed the first confirmed natural spawning of Yangtze sturgeon in the wild in decades, offering cautious hope.

## Why is caviar so damaging to sturgeon populations?
Caviar is harvested from female sturgeon eggs, and in wild fisheries this almost always means killing the fish. A large beluga female can produce up to 100 kg of roe worth tens of thousands of dollars, creating enormous financial incentive to poach even at low population densities. Because females take 20–25 years to reach first maturity, removing a single breeding female eliminates decades of future reproductive output from the population.

## Are any sturgeon species safe from extinction?
Of the 26 surviving species in the order Acipenseriformes, none is currently assessed as Least Concern. North American species such as lake sturgeon have shown some stability thanks to decades of commercial fishing bans and hatchery support, but they remain vulnerable given their slow reproduction and ongoing habitat pressures. All sturgeon continue to face existential risk without sustained management.

## How do dams affect sturgeon?
Sturgeons are anadromous, meaning they migrate from saltwater feeding grounds into freshwater rivers to spawn on specific gravel beds. Hydropower dams block these migration corridors completely. The Iron Gate dams on the Danube, for example, confine migratory sturgeons to approximately 860 km of the lower river, eliminating access to historic breeding sites across Hungary, Austria and Germany. On the Volga, dam construction reduced available beluga spawning habitat to just 12% of its former extent. Without fish-passage infrastructure — which few major dams on sturgeon rivers currently provide — entire river sections become reproductively inaccessible.

## Can aquaculture save wild sturgeon?
Aquaculture produces most of the world's legal caviar today and reduces pressure on wild stocks, but it cannot restore self-sustaining wild populations on its own. Hatchery-reared fish must still navigate polluted, fragmented rivers when released, and genetic diversity can narrow in captive populations over generations. Conservation scientists view hatchery restocking as a bridge measure — essential in the short term to prevent collapse — but insist that habitat restoration, anti-poaching enforcement, and dam mitigation are the only paths to genuine recovery.

## Is it legal to buy and sell sturgeon caviar?
International commercial trade in all sturgeon species is regulated by CITES. Two species — the Baltic sturgeon (Acipenser sturio) and the shortnose sturgeon (Acipenser brevirostrum) — are listed under CITES Appendix I, meaning no commercial international trade is permitted. All other species are listed under Appendix II, requiring export permits and import documentation. The United States banned import of wild beluga caviar in 2005. Illegal trade persists regardless: surveys in several Eastern European countries found a significant proportion of caviar products on sale without legal documentation.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/shoebill): Shoebill — wildlife guide.

## One-line answer
The shoebill (Balaeniceps rex) is a Vulnerable African swamp bird famous for its massive shoe-shaped bill and motionless hunting posture; roughly 5,000–8,000 individuals remain in Central and East African wetlands.

## Introduction
The shoebill (Balaeniceps rex) is one of Africa's most unmistakable birds — a tall, grey, stork-like waterbird with an enormous shoe-shaped bill and a patient, almost unnerving stillness. Standing up to 1.4 m tall with a wingspan near 2.5 m, it hunts in papyrus swamps and floating wetlands of Central and East Africa, spearing lungfish, catfish and juvenile crocodiles with a bill that can exceed 19 cm in length. Listed as Vulnerable on the IUCN Red List with an estimated 5,000–8,000 individuals and a decreasing population trend, the shoebill faces habitat drainage, nest disturbance, illegal capture for zoos and drowning in fishing nets. Uganda's Mabamba Swamp and Zambia's Bangweulu Wetlands are among the best-known strongholds — but the species needs intact wetland corridors across South Sudan, DRC and Tanzania to survive long term.

## Takeaway
The shoebill's bill is one of the largest among living birds — adapted to grasp lungfish and other swamp prey.

## Takeaway
Shoebills hunt by standing motionless for long periods, then striking with explosive speed.

## Takeaway
Vulnerable on the IUCN Red List — wetland drainage and nest disturbance are primary threats.

## Takeaway
Central and East African papyrus swamps — Uganda, South Sudan, Zambia, Rwanda — hold most populations.

## Takeaway
Illegal capture for zoos and drowning in fishing nets add mortality beyond habitat loss.

## What is a shoebill?
The shoebill is the sole living species in genus Balaeniceps and family Balaenicipitidae — phylogenetically placed among pelicans and hamerkops despite its stork-like appearance. Adults are mostly grey with a small crest, pale eyes and long black legs. Juveniles are browner. The bill is broad, hooked at the tip and deeply keeled — shaped to grip slippery lungfish (Protopterus) and other swamp vertebrates. Shoebills are largely silent except for bill-clapping displays and rare low murmurs at the nest. They can live 35 years or more in captivity; wild lifespan is less documented but likely decades with sufficient wetland food.

## Where does the shoebill live?
Shoebills inhabit freshwater swamps with papyrus, reeds and floating vegetation — especially where lungfish and catfish abound. Range spans South Sudan, Uganda, western Tanzania, Rwanda, eastern DRC, northern Zambia and patchily Central African Republic. They are absent from coastal mangroves and arid zones. Home ranges are large and tied to ephemeral flood cycles — birds move as water levels rise and fall. Mabamba Bay on Lake Victoria (Uganda) and Bangweulu Wetlands (Zambia) support tourism that funds local guards — when nest disturbance is controlled, breeding success improves.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/shoebill): Shoebill — wildlife guide.

## How does a shoebill hunt?
Shoebills are ambush predators — they stand frozen for minutes or hours, then lunge forward with wings spread for balance, snapping the bill shut on prey. Lungfish are a staple; frogs, snakes, monitor lizards, juvenile crocodiles and small waterbirds are also taken. Prey is decapitated or shaken before swallowing. Shoebills are solitary outside breeding — pairs defend nesting territories on floating platforms or papyrus mats. Two eggs are typical; siblicide often leaves one fledgling — a slow reproductive strategy that magnifies population sensitivity to disturbance.

## Why is the shoebill Vulnerable?
The IUCN lists the shoebill as Vulnerable — population estimated at 5,000–8,000 and decreasing. Wetland conversion for agriculture, rice schemes and oil exploration drains core habitat. Nest trampling by cattle and disturbance from poorly managed tourism reduce breeding output. Illegal live capture for Middle Eastern and Asian zoos removes wild birds — CITES Appendix II regulates international trade but enforcement is weak. Bycatch and entanglement in fishing nets drown birds in shared waterways. Climate-driven shifts in flood timing may desynchronise shoebill breeding from lungfish availability — research ongoing.

## WARN work
WARN does not currently operate field projects in shoebill range countries — Uganda, South Sudan and Zambia lie outside WARN's active partner network in South Asia, Southeast Asia and South America. This guide is offered as free educational content linking African wetland conservation to the broader habitat-protection case WARN makes globally. Healthy wetlands in any continent underpin species from shoebills to freshwater turtles — habitat appeals fund partner-led protection where WARN does operate.

## Donation hook
Wetland habitats that sustain shoebills face the same drainage and fragmentation pressures as freshwater ecosystems worldwide. Supporting WARN habitat protection helps fund partner-led work keeping critical landscapes intact for wildlife and communities.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/shoebill): Shoebill — wildlife guide.

## Why is it called a shoebill?
The bill resembles a wooden shoe or clog — broad, flattened and hooked at the tip — unlike the narrow beaks of herons or storks.

## Is the shoebill a stork or a pelican?
Neither traditionally — molecular studies place shoebills closest to pelicans and hamerkops in order Pelecaniformes, though morphology is unique.

## How many shoebills are left?
IUCN estimates roughly 5,000–8,000 individuals globally — Vulnerable with a decreasing trend.

## Where can you see shoebills in the wild?
Uganda (Mabamba Swamp), Zambia (Bangweulu), South Sudan and Rwanda host guided tourism — choose operators that keep distance from nests.

## Are shoebills dangerous?
They can strike with the bill if cornered — powerful enough to injure a person. Wild birds should never be approached closely.

## What threatens shoebills most?
Wetland habitat loss, nest disturbance, illegal capture for zoos and drowning in fishing nets — climate shifts in flooding patterns add longer-term risk.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/bullfrog): American Bullfrog — wildlife guide.

## One-line answer
The American bullfrog (Lithobates catesbeianus) is North America's largest frog, reaching 9 to 20 cm in body length and weighing up to about 0.5 kg. It lives in and around ponds, lakes, marshes and slow streams, where the male's deep, resonant call carries far across the water.

## Introduction
The American bullfrog (Lithobates catesbeianus) is North America's largest frog, reaching 9 to 20 cm in body length and weighing up to about 0.5 kg. It lives in and around ponds, lakes, marshes and slow streams, where the male's deep, resonant call carries far across the water. A voracious carnivore, it will eat almost anything it can swallow, from insects to fish and small vertebrates. In the wild bullfrogs live around seven to nine years.

## Takeaway
The American bullfrog is a heavyweight among frogs, with a body 9 to 20 cm (3.5 to 8 inches) long and a weight of up to about 0.5 kg (1.1 lb).

## Takeaway
Bullfrogs are ambush carnivores with an enormous appetite and famously indiscriminate tastes.

## Takeaway
On land the bullfrog travels in long, powerful hops, launching itself with muscular hind legs that let it clear several times its own body length in a single leap.

## Size and appearance
The American bullfrog is a heavyweight among frogs, with a body 9 to 20 cm (3.5 to 8 inches) long and a weight of up to about 0.5 kg (1.1 lb). Its skin is olive-green to brownish, often mottled, with a pale, sometimes yellow throat in breeding males. A prominent fold of skin curves around each large, exposed eardrum, or tympanum, which in males is noticeably bigger than the eye. Powerful, fully webbed hind feet make it a strong swimmer and an impressive jumper.

## Diet and feeding
Bullfrogs are ambush carnivores with an enormous appetite and famously indiscriminate tastes. They eat insects, fish and small vertebrates, and larger individuals will take anything they can cram into their mouths, including other frogs, small snakes, mice, and even ducklings. The frog sits motionless until prey comes within range, then lunges forward and engulfs it, using its bulging eyes to help push the meal down its throat. This willingness to eat almost anything has helped it thrive across a wide range of wetlands.

## Movement on land and water
On land the bullfrog travels in long, powerful hops, launching itself with muscular hind legs that let it clear several times its own body length in a single leap. In the water it is an accomplished swimmer, its webbed feet driving it forward with strong kicks and its top speed reaching around 16 km/h (10 mph). When startled at the water's edge it will make a rapid dive, kicking down into mud or vegetation to hide. This ability to both hop and swim lets it move easily between land and water to hunt and escape danger.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/bullfrog): American Bullfrog — wildlife guide.

## The bullfrog's call
The bullfrog takes its name from the male's deep, booming call, often written as a resonant jug-o-rum that carries far across a pond on warm nights. He produces the sound by pumping air back and forth over his vocal cords while inflating a large throat sac, and the low pitch travels much further than the calls of smaller frogs. Males call to defend territory and to attract females during the breeding season, and a chorus of many bullfrogs can be heard from a considerable distance. Each male's call also signals his size, since bigger frogs produce deeper notes.

## Life cycle and tadpoles
Bullfrogs breed in late spring and summer, and a single female can lay a film of up to twenty thousand eggs across the water's surface. The tadpoles are exceptionally large and can take one to three years to complete their transformation into froglets, depending on climate. During this long larval stage they graze on algae and plant matter before switching to a carnivorous adult diet. Adult bullfrogs typically live around seven to nine years in the wild.

## WARN work
WARN does not run a dedicated american bullfrog programme — this guide is part of the World Animal Rescue Network's free educational library. The american bullfrog is currently widespread and not globally threatened, and this guide helps readers understand the pressures that can change that. Building public understanding of species like the american bullfrog supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

## Donation hook
If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/bullfrog): American Bullfrog — wildlife guide.

## How big do American bullfrogs get?
They are North America's largest frog, with a body 9 to 20 cm (3.5 to 8 inches) long and a weight of up to about 0.5 kg (1.1 lb). Females tend to be slightly larger than males.

## What do bullfrogs eat?
Bullfrogs are carnivores with a huge appetite, eating insects, fish and small vertebrates. Large individuals will swallow almost anything that fits in their mouths, including other frogs, small snakes, mice and even ducklings.

## Why are bullfrogs so loud?
Male bullfrogs make a deep, resonant call by pumping air over their vocal cords and inflating a large throat sac. The low pitch carries far across water, helping them defend territory and attract females.

## How long do bullfrogs live?
In the wild American bullfrogs live around seven to nine years. Their tadpoles alone can take one to three years to transform into froglets before adulthood.

## Can bullfrogs jump far?
Yes. Their powerful hind legs let them leap several times their own body length in a single hop. In water they are also strong swimmers, reaching speeds of around 16 km/h (10 mph).

## Are bullfrogs invasive?
Outside their native eastern North America they can be highly invasive. Their enormous appetite and rapid breeding let them outcompete and eat native amphibians where they have been introduced, making them a problem in parts of the western United States and beyond.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/cane-toad): Cane Toad — wildlife guide.

## One-line answer
The cane toad is a large, warty terrestrial toad native to the Americas, reaching up to 1 kg (2.2 lb). It secretes a powerful toxin from glands on its shoulders and is famous as a destructive invasive species in Australia, where it was introduced in 1935.

## Introduction
The cane toad is a large, warty terrestrial toad native to the Americas, reaching up to 1 kg (2.2 lb). It secretes a powerful toxin from glands on its shoulders and is famous as a destructive invasive species in Australia, where it was introduced in 1935. Cane toads commonly live 10 to 15 years.

## Takeaway
Cane toads are mostly active at night and are not shy of human settlements, often gathering under lights to catch insects.

## Takeaway
Unusually for amphibians, cane toads are opportunistic omnivores.

## Takeaway
The cane toad is native to the southern United States, Central America, and northern South America.

## Behavior and toxicity
Cane toads are mostly active at night and are not shy of human settlements, often gathering under lights to catch insects. Their main defense is bufotoxin, a potent poison stored in the large parotoid glands behind the eyes. Predators that bite or swallow a cane toad can be sickened or killed, which is why the species is so damaging where native animals have no resistance.

## Diet and feeding
Unusually for amphibians, cane toads are opportunistic omnivores. They eat beetles, ants, and other insects, but also small reptiles, frogs, rodents, and even pet food or kitchen scraps. This flexible diet helps them thrive in disturbed and human-modified habitats.

## Habitat and range
The cane toad is native to the southern United States, Central America, and northern South America. It was deliberately introduced to many regions, most infamously to Australia in 1935 to control sugarcane beetles. There it spread rapidly and became one of the country's worst invasive species.

## Conservation
In its native range the cane toad is listed as Least Concern and is not threatened. The conservation concern is the opposite: where it has been introduced, it poisons native predators and disrupts ecosystems. Management focuses on limiting its spread and protecting vulnerable native wildlife.

## WARN work
WARN does not run a dedicated cane toad programme — this guide is part of the World Animal Rescue Network's free educational library. The cane toad is currently widespread and not globally threatened, and this guide helps readers understand the pressures that can change that. Building public understanding of species like the cane toad supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

## Donation hook
If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/cane-toad): Cane Toad — wildlife guide.

## Are cane toads poisonous?
Yes. Cane toads secrete a powerful toxin called bufotoxin from glands behind their eyes. It can sicken or kill predators and pets that bite or swallow the toad.

## Why are cane toads a problem in Australia?
Cane toads were introduced to Australia in 1935 to control crop pests but instead spread widely. Their toxin kills native predators that have no resistance, making them one of Australia's most damaging invasive species.

## What do cane toads eat?
Cane toads are omnivores. They eat insects such as beetles and ants, as well as small reptiles, frogs, rodents, and even pet food or scraps.

## How big do cane toads get?
Cane toads commonly reach 10 to 15 cm (4 to 6 in) and can weigh up to about 1 kg (2.2 lb), making them one of the largest toads in the world.

## How long do cane toads live?
In the wild cane toads typically live 10 to 15 years, and they can live even longer in captivity.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/goliath-frog): Goliath Frog — wildlife guide.

## One-line answer
The Goliath frog is the largest living frog, growing up to 32 cm (13 in) long and weighing as much as 3.3 kg (7.3 lb). It lives only in fast-flowing rivers of Cameroon and Equatorial Guinea in West Africa.

## Introduction
The Goliath frog is the largest living frog, growing up to 32 cm (13 in) long and weighing as much as 3.3 kg (7.3 lb). It lives only in fast-flowing rivers of Cameroon and Equatorial Guinea in West Africa. This powerful frog is endangered and can live around 15 years.

## Takeaway
Despite their size, Goliath frogs are wary and quick to dive into rushing water when disturbed.

## Takeaway
Goliath frogs are carnivores that ambush prey near and in fast water.

## Takeaway
This giant frog has a small range in the rainforests of Cameroon and Equatorial Guinea, where it depends on clean, fast-flowing rivers and waterfalls.

## Behavior and strength
Despite their size, Goliath frogs are wary and quick to dive into rushing water when disturbed. They are remarkably strong and have been observed moving rocks weighing several kilograms to build small breeding pools at the river's edge. Lacking a vocal sac, they communicate with whistles and an open-mouthed call rather than a typical croak.

## Diet and feeding
Goliath frogs are carnivores that ambush prey near and in fast water. Adults eat insects, crustaceans, worms, fish, and other amphibians, and large individuals can take small snakes or even baby turtles. Powerful hind legs let them lunge at prey and leap several meters.

## Habitat and range
This giant frog has a small range in the rainforests of Cameroon and Equatorial Guinea, where it depends on clean, fast-flowing rivers and waterfalls. It needs well-oxygenated water and rocky riverbanks for breeding. Its narrow habitat makes it especially vulnerable to disturbance.

## Conservation
The Goliath frog is listed as Endangered, with populations falling due to habitat destruction from logging and agriculture, river pollution, and collection for food and the pet trade. Its limited range and slow reproduction make recovery difficult. Protecting intact river forest is essential to its survival.

## WARN work
WARN does not run a dedicated goliath frog programme — this guide is part of the World Animal Rescue Network's free educational library. The goliath frog faces documented conservation pressure in the wild, which is why clear, sourced public information about it matters. Building public understanding of species like the goliath frog supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

## Donation hook
If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/goliath-frog): Goliath Frog — wildlife guide.

## How big is the Goliath frog?
The Goliath frog is the largest frog in the world, reaching up to 32 cm (13 in) in body length and weighing as much as 3.3 kg (7.3 lb).

## Where do Goliath frogs live?
They live only in a small area of West Africa, in the fast-flowing rainforest rivers and waterfalls of Cameroon and Equatorial Guinea.

## What do Goliath frogs eat?
Goliath frogs are carnivores that eat insects, crustaceans, worms, fish, and other amphibians. Large individuals can even take small snakes or baby turtles.

## Are Goliath frogs endangered?
Yes. The Goliath frog is listed as Endangered by the IUCN, mainly due to habitat loss, river pollution, and collection for food and the pet trade.

## Can Goliath frogs jump far?
Yes. Their powerful hind legs allow them to leap several meters in a single jump, helping them escape predators and capture prey.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/glass-frog): Glass Frog — wildlife guide.

## One-line answer
Glass frogs are small tree frogs of Central and South American rainforests, famous for the translucent skin on their bellies that reveals their internal organs and beating heart. They are nocturnal, arboreal, and care for their eggs on leaves above streams.

## Introduction
Glass frogs are small tree frogs of Central and South American rainforests, famous for the translucent skin on their bellies that reveals their internal organs and beating heart. They are nocturnal, arboreal, and care for their eggs on leaves above streams. Most species live around 10 to 14 years.

## Takeaway
Glass frogs are named for the translucent skin on their undersides, through which the heart, liver, and digestive tract can be seen.

## Takeaway
These tiny frogs are insectivores that hunt at night among leaves near streams.

## Takeaway
Glass frogs live in humid montane and lowland rainforests of Central and South America, almost always near clear, flowing streams.

## Behavior and transparency
Glass frogs are named for the translucent skin on their undersides, through which the heart, liver, and digestive tract can be seen. Recent research found that some glass frogs become even more transparent while sleeping by tucking red blood cells into their liver. Their green backs help them blend with leaves by day, while they are active and vocal at night.

## Diet and feeding
These tiny frogs are insectivores that hunt at night among leaves near streams. They eat small insects such as flies, crickets, and ants, as well as spiders, snatching them with a quick tongue. Their small size limits them to equally small prey.

## Habitat and range
Glass frogs live in humid montane and lowland rainforests of Central and South America, almost always near clear, flowing streams. Males often guard clutches of eggs laid on leaves overhanging the water, so that hatching tadpoles drop into the stream below. They depend on clean water and dense streamside plants.

## Conservation
Many glass frog species are listed as Least Concern, but they are highly sensitive to deforestation, water pollution, and the amphibian fungal disease chytridiomycosis. Because they need pristine streams, they are useful indicators of rainforest health. Some narrow-range species are threatened or poorly known.

## WARN work
WARN does not run a dedicated glass frog programme — this guide is part of the World Animal Rescue Network's free educational library. The glass frog is currently widespread and not globally threatened, and this guide helps readers understand the pressures that can change that. Building public understanding of species like the glass frog supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

## Donation hook
If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/glass-frog): Glass Frog — wildlife guide.

## Why are glass frogs transparent?
Glass frogs have translucent skin on their bellies that lets you see their internal organs, including the beating heart. The transparency is thought to help them blend in and avoid detection by predators.

## What do glass frogs eat?
Glass frogs are insectivores that eat small insects such as flies, crickets, and ants, along with spiders, hunting at night among streamside leaves.

## Where do glass frogs live?
They live in humid rainforests of Central and South America, almost always near clear, flowing streams where they breed on overhanging leaves.

## How big are glass frogs?
Glass frogs are very small, with most species measuring only about 2 to 3 cm (0.8 to 1.2 in) in body length.

## Do glass frogs care for their eggs?
Yes. In many species the male guards the eggs, which are laid on leaves above a stream, keeping them moist and protected until the tadpoles hatch and drop into the water.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/hellbender): Hellbender — wildlife guide.

## One-line answer
The hellbender is the largest salamander in North America, reaching up to 74 cm (29 in) long. It is fully aquatic, living its whole life in clean, fast-flowing streams where it breathes mainly through the wrinkled folds of its skin.

## Introduction
The hellbender is the largest salamander in North America, reaching up to 74 cm (29 in) long. It is fully aquatic, living its whole life in clean, fast-flowing streams where it breathes mainly through the wrinkled folds of its skin. Hellbenders are long-lived, often surviving 25 to 30 years.

## Takeaway
Hellbenders are secretive, mostly nocturnal salamanders that hide by day under large flat rocks in the streambed.

## Takeaway
Hellbenders are carnivores whose diet is dominated by crayfish, along with small fish and aquatic insects.

## Takeaway
This giant salamander lives in cool, clear, fast-flowing rivers and streams of the eastern and central United States, particularly in the Appalachian region.

## Behavior and breathing
Hellbenders are secretive, mostly nocturnal salamanders that hide by day under large flat rocks in the streambed. They are fully aquatic and absorb most of their oxygen directly through the heavily wrinkled folds of skin along their bodies, which increase surface area in cool, oxygen-rich water. They rarely leave the stream and rely on clean, flowing water to survive.

## Diet and feeding
Hellbenders are carnivores whose diet is dominated by crayfish, along with small fish and aquatic insects. They hunt at night, using suction and a quick sideways snap of the jaws to capture prey. Healthy crayfish populations are essential to their survival.

## Habitat and range
This giant salamander lives in cool, clear, fast-flowing rivers and streams of the eastern and central United States, particularly in the Appalachian region. It needs rocky stream bottoms with large flat stones for shelter and nesting. Because it breathes through its skin, it is extremely sensitive to silt and pollution.

## Conservation
Hellbenders are listed as Vulnerable and have declined sharply across much of their range. The main threats are water pollution, siltation from erosion, dams, and disease, all of which degrade the clean streams they depend on. Captive breeding and stream restoration programs are working to recover populations.

## WARN work
WARN does not run a dedicated hellbender programme — this guide is part of the World Animal Rescue Network's free educational library. The hellbender faces documented conservation pressure in the wild, which is why clear, sourced public information about it matters. Building public understanding of species like the hellbender supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

## Donation hook
If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.


World Animal Rescue Network (https://worldanimalrescuenetwork.org/wildlife-guides/hellbender): Hellbender — wildlife guide.

## How big do hellbenders get?
Hellbenders are the largest salamanders in North America, reaching up to about 74 cm (29 in) in length and weighing as much as 1.5 kg (3.3 lb).

## How do hellbenders breathe?
Hellbenders breathe mainly through their skin. The loose, wrinkled folds along their body greatly increase surface area, letting them absorb oxygen directly from cool, fast-flowing water.

## What do hellbenders eat?
Hellbenders are carnivores that feed mostly on crayfish, along with small fish and aquatic insects, hunting at night on the streambed.

## Are hellbenders endangered?
Hellbenders are listed as Vulnerable by the IUCN and have declined across much of their range due to water pollution, siltation, dams, and disease.

## Are hellbenders dangerous to people?
No. Despite their fearsome name and appearance, hellbenders are harmless to humans. They are not venomous and pose no threat; they are simply large, secretive stream salamanders.