Amphibians Under Threat

The April 2009 issue of National Geographic Magazine has an article about the dramatic, worldwide decline of amphibians (frogs and salamanders) due to a fungus that has been spreading rapidly over the last couple of decades.

The fungus, chytridiomycosis, targets the protein keratin which increases in frogs as they mature. So, a pond with the fungus may be teeming with tadpoles, but have no adult frogs. (And once those frogs mature, they will die too, and then the source of future tadpoles is gone...)

Even areas that are remote from civilization, like lakes high up in the Sierra mountains, have seen devastating die offs of frogs as the fungus has reached those seemingly isolated spots. The following quote seems to sum up the problem:

" 'Today's amphibians have taken not just a one-two punch, but a one-two-three-four punch. It's death by a thousand cuts,' says University of California, Berkeley, biol­ogist David Wake. Habitat destruc­tion, the introduction of exotic species, commercial exploitation, and water pollution are working in concert to decimate the world's amphibians."

Add to these other items the spread of the chytrid fungus, and the population of frogs and salamanders across the planet are in trouble. Hundreds of species have already gone extinct. Many other species are now found only in captivity, where scientists hope they can keep them around through breeding programs, and then reintroduce them to the wild once (if?) the situation with the fungus is resolved.

"Why care about frogs? 'I could give you a thousand reasons,' says herpetologist Luis Coloma. Because their skin acts not only as a protective barrier but also as a lung and a kidney, they can provide an early warning of pollutants. Their insect prey carries human pathogens, so frogs are an ally against disease. They serve as food for snakes, birds, even humans, playing a key role in both freshwater and terrestrial ecosystems. 'There are places where the biomass of amphibians was once higher than all other vertebrates combined,' says David Wake. 'How can you take that out of the ecosystem without changing it in a major way? There will be ecological consequences that we haven't yet grasped.' "

It all goes back to Aldo Leopold's rule about intelligent tinkering: be sure you keep all the parts.

For a quick slide show of frogs from around the world, click here!

Have you Hugged Your Salamander Today?

Meet the Tiger Salamander Ambystoma tigrinum, one of the few salamader species found in McHenry County. Our local Tigers can be as large as 14 inches, but are more likely to be 6-8 inches long. You are most likely to find one of these guys in a moist woodland under leaf litter - they tend to be very private, probably to avoid predators!

There are about 500 species of salamader worldwide, with the largest type found in China, and weighing in at 140 pounds and nearly 6 feet long!

In Illinois, the largest salamander is called a Hellbender, and can be two and a half feet long. They are found in fast moving streams in the southern part of the state, so don't expect to see one in McHenry County!

The Great Smoky Mountain National Park in North Carolina is considered the salamander capital of the World, boasting 30 different species ranging from the inch and a half long pygmy salamander to the 30 inch hellbender!

Salamanders are amphibians, meaning they spend part of their life on the land and part in the water. They are most closely related to frogs and toads, although they may visually resemble lizards (or snakes with little feet). Their skin must be kept moist or they dry up and die.

Many, but not all, salamanders breathe through their skin, making them highly susceptible to pollutants like pesticides or other chemicals, as these things are absorbed directly through the skin and into the organs.

Salamanders fill an important niche in the overall food chain. They are carnivores, meaning they eat other animals like insects, eggs, small fish, and even small rodents or young frogs. In turn, they are eaten by raccoons, possums, large birds like herons and hawks, snakes, turtles and other medium-sized carnivores.

Following the first big rain in the spring, when temporary pools of water flood, salamanders emerge from hibernation, and head out in search of something to eat and a place where they can meet salamanders of the opposite gender! This drive to reproduce often results in so-called "breeding events" in the temporary pools, where several salamanders gather to lay and fertilize eggs. (Kind of a salamander orgy.)

However, because the salamander is a small, reclusive critter, any given salamander is unlikely to have the opportunity to breed more than once in its lifeime! So, if you happen to chance upon a salamander breeding event in your local vernal pool one spring, just look away, and let them enjoy the party -- it might be the only party any of them ever attend!