Why worry about frogs?


First off, I should point out that the image shown here is of a toad, not a frog.  The honest truth is that I wasn’t sure what it was when I photographed it.  I was walking with my daughters in a childrens’ play area near a local wildlife reserve when we spotted it hopping across our path. The kids were delighted, and so was I. It was only later on that my learned colleague, Stephen Price, pointed out that it was a toad. You see, I am in no way an expert on amphibians. I just like them, and in the course of some recent research, I happen to have also discovered that they are terribly important to human wellbeing.

In case, like me, you are also not an amphibian expert (and if you are, please feel free to skip to the next paragraph, or perhaps to comment on this post and correct me where necessary – it is highly likely that some corrections are needed!), amphibians include frogs, toads, newts, salamanders and caecilians (which look a bit like large earthworms, and live almost entirely underground or underwater: see Amphibian Ark).  My fascination with amphibians, like that of many people, arose from the astonishment I felt as a child when witnessing the process of metamorphosis taking place, as frogspawn became tadpoles and then froglets, in my own back garden.

This fascination, combined with my veterinary interests, led to my recent publication of an article on the detection and reporting of an important amphibian disease, Ranavirus. I found that there is a need to harmonise methods of testing for and reporting the disease, to improve the collection of data which will help us to understand and perhaps mitigate the effects of the disease.  It’s a difficult task, to gather information from many sources and present it so that it can be utilised and understood.  You may ask, why is it worth the effort?

In the first place, diseases like Ranavirus can drastically affect numbers of amphibians. The Center for Biological Diversity asserts that earth is currently in the midst of the sixth mass extinction event of the past half billion years. The global amphibian assessment of 2004 found that amphibians were more threatened, and were declining more rapidly, than either birds or mammals. Amphibian declines are significant.

In the second place, humans trade in amphibians, and the movement of amphibians in this trade has contributed to the emergence of ranavirus as a threat to amphibian survival. We are culpable in the spread of the disease, and also capable of limiting it.  But again, you could ask why? Why does it matter if there are a few less frogs around? There are so many things to concern us in the world right now.  Do frogs (or toads, newts, whatever) really matter?

Of course, you’ve guessed that I am going to tell you that they do.  But they really, really do. Because to lose species upon species of amphibian is to lose huge amounts of genetic material. This material, the earth’s biodiversity, is our planet’s bank account.  To cope with changes (and there are certainly plenty of those around), the living planet needs to have the genetic capacity to adapt.  Apart from being a genetic resource, amphibians can be sources of food and of medicines. They also perform important functions (or ecosystem services). By eating and competing with mosquitoes, they control numbers of these insects, which transmit diseases such as malaria.   They are involved nutrient cycling, which produces fertile soil, so they assist in food production, even for those of us who don’t eat frogs.

Amphibians are fascinating.  I want my children’s children to see them metamorphosing, just as I did.  So I think they are inherently worth protecting.  But perhaps a bigger motivation is that if we don’t protect these species, our own species will suffer as a consequence.

Read more on the importance of amphibians in my article for The Conversation, on Great Crested Newts.