More than 6,700 species of amphibians (frogs, toads, and salamanders) have been identified on earth. however, studies show that many populations have declined or vanished recently. 1. why are amphibian populations declining? explain at least two reasons thoroughly. 2. what specific actions are being taken to declining amphibian populations? 3. why is the loss of amphibian populations significant? why should we care? 4. similarly but on a larger scale, tropical rainforest ecosystems are also disappearing. why is this loss significant?