When April’s National Geographic came in the mail, I ripped into it eagerly. I flipped through the pages, looking at the breath-taking photography, and saw an article on the worldwide frog crisis. Immediately, I started talking to the Spousal Unit about the article, and how I hoped to learn more. I was expecting him to already have the basic knowledge that I had. After all, he works for a research university, in a department that specifically deals with animal research. He also sends me cool science articles, plenty of them about ecology, on a regular basis. Plus, there’s a huge wall of information about this very topic at our local zoo. Still, if he didn’t know about it, I realized that what I considered to be common knowledge probably is not. I’ve done a lot of reading on this issue, so I’ll do my best to give a layman’s summary.
Since the 1980s, the worldwide amphibian population has been disappearing. This isn’t an isolated issue in certain regions of the world, or only previously known threatened or endangered species. This is a mass extinction, where the biodiversity of the world is being destroyed. Yes, local issues play a part, but around a third of all amphibian populations are threatened. In particular, the frog population is diminishing at an astonishing rate. The problem has many roots, and isn’t completely understood by scientists. A few known factors are habitat destruction, climate change, pollution, and disease.
Since amphibians are affected by changes in both land and water habitats, they are doubly at risk when their world is polluted. Amphibians take in needed oxygen through their skin. Deforestation deprives many of these animals of a home. Humans hold most of the blame for habitat destruction and pollution that is devastating their lands, of course. Several diseases are rampaging the populations as well. The introduction of non-native species, such as trout, also contributes to the decline.
The chytridiomycosis, or chytrid, fungus is particularly virulent. (Actually, can I really use the word “virulent” to describe a fungus? Oh well, I just did. Onward.) One theory is that the disease originated from African clawed frogs. These frogs were initially exported for pregnancy tests and make up the majority of frogs used in research at many universities today. Human scrambling of ecosystems strikes again. Chytrid has spread to every continent amphibians are found. It does not kill carrier infant populations, but adults are dying everywhere.
Amphibians play a vital role in the food chain, controlling rid of insect populations and providing food for other animals. That web is a delicate balance, and tampering with it can have unforeseen effects on humans down the road. Frogs, especially, are used widely in medicines. They are filled with substances that are of use to humans. Amphibians are used in all sorts of research, teaching us about the world. They are considered bioindicators. That very fragility that makes them susceptible to changes in the environment is also used as an indicator of general health. If all the frogs are dead, well, we’ve pretty much fouled things right up, haven’t we?
Humans may be to blame for many of the causes, but we’re also working on solving the issue. For the common person, the most responsible step is to reduce your “ecological footprint.” We should all be mindful of the way we’re walking through the world in general anyway. Research into other issues, and integrated solutions are escalating. Now that chytrid has been identified as a major culprit, there are some promising advances in treating by capture and rerelease into the home environment. Since tadpoles can be carriers, this is very hopeful. The Amphibian Ark project focuses on protecting a captive population of 500 species to be released whenever the crisis seems to have stabilized. Scientists are working on regenerating homes for these froggies. The video I linked to yesterday is an example of the types of work that will be necessary to make ecosystems for ready amphibians to reinhabit.
