Amphibians, Reptiles and Fish
Alligator | Alligator Snapping Turtle | Arboreal Salamander | Black Rat Snake | Bull Shark | California Red-Legged Frog | Cheat Mountain Salamander | Chinook Salmon | Eastern Box Turtle | Eastern Fence Lizard | Flying Fish | Louisiana Pine Snake | Mangrove Rivulus | Mudminnows | Puerto Rican Boa | Puerto Rican Coqui | Pupfish | Rattlesnakes | Rainbow Trout or Steelhead | Sawfish | Sea Turtles | Southern Cricket Frog | Spotted Salamander | Texas Blind Salamander | Tiger Salamander | Tree Frogs | Toads | Wood Frog
To identify an animal as an amphibian, it should have each of these characteristics:
- Amphibians have a backbone. They are vertebrates.
- Amphibians are cold-blooded. They cannot regulate their own body temperature.
- Amphibians spend at least part of their lives in water and on land.
- Amphibians do not have scales and their skin is permeable (molecules and gases can pass through).
- Amphibians have gills for at least part of their lives. Some species have gills only as larvae, while others can have gills throughout their lives.
- Most amphibians go through metamorphosis.
Amphibians are frogs, toads, salamanders, caecilians and newts. Some common amphibians are bullfrogs, American toads, mole salamanders and hellbenders. What amphibians can you identify in your community?
To identify an animal as a reptile, it should have each of these characteristics:
- Reptiles have a backbone. They are vertebrates.
- Reptiles are covered in scales.
- Reptiles breathe with lungs.
- Most reptiles lay eggs. Some reptiles, like the boa constrictor, give birth to live young.
- Almost all reptiles are cold-blooded. One of the exceptions is the leatherback sea turtle, which can regulate its body temperature to some degree.
Some common reptiles are the American alligator, garter snakes, sea turtles and a monitor lizard. What reptiles can you identify in your neighborhood?
To identify an animal as a fish, it should have these characteristics:
- Fish live in water.
- Fish have a backbone. They are vertebrates.
- Fish breathe using gills. They absorb oxygen through the gills.
- Almost all fish are cold-blooded. Two of the exceptions are the tuna and the Pacific salmon shark, which can raise their body temperature to some degree.
- Some fish have scales.
Some common fish are catfish, sharks, salmon, trout and sturgeon. What fish can you identify in your local stream, pond or wetland?
How are Amphibians, Reptiles and Fish Doing Worldwide and in the United States?
The International Union for Conservation of Nature (IUCN) Red List reports that an estimated ~8,700 reptiles, ~6,340 amphibians and ~30,000 fish have been identified worldwide. These numbers are continuously changing as scientists make new discoveries and classifications. Of the 1,385 reptile species studied by the IUCN, 31% are threatened or extinct. 37% of the 3,481 fish species studied are threatened or extinct.
Amphibians are the most threatened class of animals in nature. They are extremely susceptible to environmental threats, because of their porous eggs, semi-permeable skin and because amphibians spend at least part of their lives in water. Every major threat, from pollution to global warming and disease, affect amphibians and this has put them at serious risk. According to the IUCN, 32% of amphibians are either threatened or extinct and over 42% are declining in number. Even more worrying is that we do not have sufficient data to study the health of a quarter of the amphibians on Earth – they could be going extinct and we would not even know.
In the United States, there are over 230 amphibians, over 280 reptiles and approximately 800 species of fish. Each of these categories has species represented on the US Endangered Species List. Together, more than 170 amphibian, reptile and fish species are threatened or endangered. A few of the familiar species on the Endangered Species List are the Chinook salmon, the steelhead, green sea turtle, and the Wyoming toad.