Animals Endangered Species 13 Amazing and Critically Endangered Frogs By Margaret Badore Senior Editor Columbia University Sarah Lawrence College Maggie Badore is an environmental reporter based in New York City. She started at Treehugger in 2013 and is now the Senior Commerce Editor. our editorial process Facebook Facebook Twitter Twitter Margaret Badore Updated September 11, 2020 Mark Newman / Getty Images Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species Introducing the frog: An animal that absorbs water through its skin and whose populations serve as an early warning sign of a decline of their aquatic habitat. These tail-less amphibians are wonderfully diverse, but sadly many species find themselves in an increasingly inhospitable world. All of the frogs featured here are listed as critically endangered by the International Union for Conservation of Nature. We hope that learning about these creatures will inspire readers to act to conserve their precious habitats. 1 of 13 Lemur Leaf Frog Frogmana / WIkimedia Commons / CC BY-SA 4.0 The lemur leaf frog (Agalychnis lemur) once found in abundance has all but vanished from Costa Rica. The species has lost over 80% of its population in Panama during the past 10 years. Like many endangered frogs, an infectious fungal disease called chytridiomycosis has led to the decline. The fungus has infected amphibians in many parts of the globe, including North and South America, the Caribbean, and Australia. 2 of 13 Dusky Gopher Frog Glen Johnson, USFWS / Flickr / CC BY 2.0 The dusky gopher frog (Lithobates sevosus) population, in the longleaf pine forests of Mississippi and Louisiana, numbers around a mere 100 frogs. Efforts to impose conservation measures gave rise to a Supreme Court case that had the frogs on the losing side. Timber interests, as well as predatory fish in stock ponds, have degraded the frog's habitat. 3 of 13 Anodonthyla Vallani Miguel Vences et al. / Wikimedia Commons / CC BY 3.0 Anodonthyla vallani faces extinction due to human threats to the single small habitat in the Ambitanetely Reserve in Madagascar they call home. Illegal woodcutting, livestock overgrazing, and forest fires hamper conservation efforts. Scientists suspect that the species would not be able to adapt to another location. Curiously, these frogs are found around nine feet off the ground in trees and remain active in dry conditions. 4 of 13 Variable Harlequin Frog Brian Gratwicke / Wikimedia Commons / CC BY-SA 3.0 Once believed to be extinct, the variable harlequin frog (Atelopus varius) only survives in one small area of Costa Rica under threat from a landslide. The range of this frog once stretched across Costa Rica to Panama. The exact reasons for this species’ decline are unknown, but habitat loss and chytridiomycosis present two possible theories. These frogs are found along streams and are active during the day. 5 of 13 Bale Mountains Treefrog Malcolm Largen / Encyclopedia of Life The Bale Mountains treefrog (Balebreviceps hillmani) only inhabits a shrinking area of tree heather of less than 2 square miles in Ethiopia's Bale Mountains National Park. Despite the seeming protection of a national park, humans are the primary threat to these frogs. The fencing of the land for cattle grazing and firewood collection makes the land inhospitable to the frogs. Long-running conservation programs in the area do not have amphibian specific efforts. 6 of 13 Williams’ Bright-eyed Frog Franco Andreone / Wikimedia Commons / CC BY 2.5 The Williams’ bright-eyed frog (Boophis williamsi), called one of the most threatened species in Madagascar, lives under constant threat of fires and habitat loss resulting from illegal logging. It lives on the mountain top of Ankaratra Massif, at an altitude of over 8,000 feet above sea level. The highly localized population numbered only 46 individuals in one survey. 7 of 13 Taita Hills Warty Frog Patrick Kinyatta Malonza / Wikimedia Commons / CC BY-SA 3.0 The Taita Hills warty frog (Callulina dawida) got its name from the severely fragmented forests of southeastern Kenya. Over half of these keystone frogs live in areas isolated because of breaks in the native habitat caused by eucalyptus and pine plantations. Fragmented habitats lead to population decline because of the high rate of inbreeding. There is some good news for this species: the Taita Hills now has protection as a key biodiversity area, and there are plans to turn some tree plantations in the area back into native forests. 8 of 13 Gregg’s Stream Frog 2012 Javier Sunyer / CalPhotos The IUCN expects the critically endangered Gregg's stream frog (Craugastor greggi) to lose over 80% of its population in the next 10 years due to chytridiomycosis fungus disease. Habitat loss in Guatemala and particularly Mexico, has also led to the decline. Gregg's stream frogs live in cloud forests and breed in freshwater streams. These tiny frogs only measure 1.4 inches from head to tail. 9 of 13 Booroolong Frog Ken Griffiths / Getty Images The booroolong frog (Litoria booroolongensis), once widespread in the Northern Tablelands of Australia, now appears to be extinct in that region. It remains as a small population in New South Wales near Tamworth. Chytridiomycosis serves as the most likely reason for the substantial decline. Weeds and willows encroaching on streams, as well as predatory non-native fish, have also harmed the population. 10 of 13 Rabb’s Fringe-limbed Tree Frog Brian Gratwicke / Flickr / CC BY 2.0 Only a single Rabb’s Fringe-limbed Tree Frog (Ecnomiohyla rabborum) has been heard since chytridiomycosis first became a threat in their area of Panama. The species is possibly already extinct and faces little chance of recovery due to luxury vacation home building and urbanization of their mountain forest home. 11 of 13 Corroboree Frog Melbourne Zoo The Corroboree Frog (Pseudophryne corroboree), native to Australia, saw a population decline of over 80% between the 1990s and early 2000s. It’s unclear what caused this loss, but conservationists have been successful at breeding these frogs in captivity. Researchers hope this captive population may one day help re-establish the Corroboree in the wild. 12 of 13 Honduras Spikethumb Frog Josiah H. Townsend / Calphotos / CC BY-SA 2.5 The Honduras spikethumb frog (Plectrohyla dasypus) was first listed as critically endangered in 2004. Another species threatened by chytridiomycosis, a 2007 survey showed 86% of the frogs infected with the fungus. Another detriment to the population is heavy foot traffic from tourism and researchers. The cultivation of coffee, flowers, and cardamom in their limited range in the Parque Nacional Cusuco, in northwestern Honduras, adds to the threats. 13 of 13 Anaimalai Flying Frog Kalyan Varma / Wikimedia Commons / CC BY-SA 3.0 Locally common, but critically endangered, Anaimalai Flying Frogs (Rhacophorus pseudomalabaricus) only thrive in unaltered subtropical mountain forests of the Indira Gandhi National Park and surrounding land. Sadly, those lands decrease yearly because of humans converting the forests into cultivated agricultural areas. These frogs have large webbed hands and feet that allow it to glide from tree to tree. What You Can Do to Help the Frogs Unfortunately, many frog species require research to determine whether they belong on the endangered list. New species of frogs are being discovered and described all the time. Protecting frog habitats is not only crucial for preventing certain species from going extinct, but also for understanding the full extent of frog diversity. The advice we give for protecting the human environment can also go a long way toward protecting the environment for all kinds of animals. Still, there are some things that you can do that particularly benefit frogs. Avoid Pesticides in Your Lawn and Garden Frogs are particularly susceptible to the chemicals used in pesticides, as work by biologists such as Dr. Tyrone Hayes has shown. Avoid using pesticides in your backyard, and you can also help support the use of fewer pesticides in agriculture by choosing organic food. Donate to a Frog-Friendly Conservation Effort Many excellent conservation efforts are going on around the world to prevent more species of frogs from going extinct. Consider donating to the Amphibian Rescue & Conservation Project in Panama or the Amphibian Ark, an organization supported by the International Union for Conservation of Nature and the World Association of Zoos and Aquariums.