Large forest fragments outside protected areas are important for sustaining amphibian diversity

Patch size matters for amphibians in tropical fragmented landscapes

Mauricio Almeida-Gomesa, Marcus Vinícius Vieiraa,Carlos Frederico Duarte Rochab,

Jean Paul Metzgerc and Greet De Costerc.

Biological Conservation, Volume 195, March 2016, Pages 89–96

Fragment size is considered to be the main factor deciding species diversity for most taxa, but it is not well known how it affects amphibian diversity. In this new study the researchers contend that may be the scale at which previous studies were conducted was too small (only few forest fragments and/or a small range of fragment sizes considered) and/or the sampling method was not the most optimal one. Here the researchers investigated whether amphibian diversity is affected by patch size in the largest study (in terms of number of fragments and range of fragment sizes) ever conducted in tropical forests. The site selected was Brazilian Atlantic Forest, a highly threatened biodiversity hotspot.

The researchers found that, larger fragments had more species, more integer communities and a larger diversity of reproductive modes than smaller ones. The researchers contend that the result of their study  indicate that continuous forests are irreplaceable for amphibian conservation, but also show that large forest fragments outside these areas are important for sustaining amphibian diversity.

The study gives the first robust empirical evidence for the importance of fragment size for amphibian persistence in tropical fragmented landscapes. It also highlights the need for an adequate sampling design and method that enable the detection of a higher number of species.