Frogs crucial to health of environment - via Herp Digest

September 16 2015 

By KAMCILLA PILLAY, LOL SciTech

Durban - Superstition and noise are the main reasons for getting rid of frogs, say experts, and as winter gives way to spring, the race to get rid of the amphibians seems to be on.

Nick Evans and Dr Jeanne Tarrant, Endangered Wildlife Trust’s Threatened Amphibian Programme’s (TAP) field officer and manager respectively, told the Daily News the animal was the most threatened of all vertebrates globally.

“A lot of people think they are bad luck, or harmful. At this time of year, as they emerge from their winter slumber, the biggest complaint from many people is about the noise our frogs, especially the toads, make at night, keeping some folk from sleeping peacefully.”

Many choose to get rid of their ponds.

“But first, think, wouldn’t you much rather have the sounds of nature than the sounds of traffic or the blaring music from a house party? Come on, it’s not so bad.”

They said that could cause people to go to “quite drastic lengths”, including moving them long distances away from their homes and, in some cases, inflicting “cruelty and death” on these small creatures.

“Frogs are crucial in our environment for many reasons. They are one of the most important animals in the food chain. In many ecosystems, especially forests, adult frogs can be extremely abundant. This is because they provide food to a vast array of animals, especially birds and other small animals, including frogs themselves.”

They said tadpoles did “a great job” in freshwater environments, by cleaning rivers, dams and ponds, by feeding on algae.

“(They) are major predators and consume a large number of insects in a single night, especially the ones people can’t stand, like flies and mosquitoes. Instead of buying all sorts of poisons to eradicate those insects, which impact our environment, let your frogs (do the work).”

They advised people to become more aware of the different frog species in Durban.

“You can go in your own garden, if you have a pond or stream. Or you can go to a local park or wetland. You would have to then go in a group though, as the world’s most dangerous animal, the human, also sometimes occur in the same areas as frogs.”

South Africa, say Nick Evans and Dr Jeanne Tarrant, Endangered Wildlife Trust’s Threatened Amphibian Programme’s (TAP) field officer and manager respectively, is ranked fourth in terms of the number of threatened amphibian species in the Afro-tropical realm.

“Overall, 43 percent of our frog species are endemic to the country, meaning they don’t occur anywhere else. Of these, 35 percent are in a threatened category, and all but one of the threatened species are endem-ic… The main threat, which affects all wildlife, is loss of habitat.

“Wetlands, river systems, grasslands and forests continue to be destroyed, thanks to an ever-increasing human population and the growing demands placed on our natural resources.”

They explained that Southern Africa had a rich diversity of amphibians with 160 known species, of about 5 500 worldwide.

“Here in KwaZulu-Natal, we are lucky to have the most species-rich and diverse area for frogs in the country. Just in and around Durban, we have over 25. We have some threatened and endangered species too, such as the critically endangered Pickersgill’s Reed Frog (who live in) around 20 wetlands. There are about five sites in greater Durban.”

Frogs, because they live in both water and on land, are regarded as “bio-indicators”.

“The presence of frogs can tell you quite a lot about a certain area, like a wetland, for example. If frogs are present, that usually means the water quality is good, which leads to the presence of insects as well. Frogs have a very sensitive skin, and actually breathe through it, so they do not cope well with pollution. If an area is polluted with chemicals and other toxins, there will be no frogs around.”

They said frogs in South Africa, unlike other places, were not toxic and so were harmless.