Sustaining turtles

Posted on March 23, 2016

Freshwater turtle populations are very vulnerable to increases in adult mortality, such as those caused by the incidental capture of turtles in commercial fishing nets. Modelling of data from Canada’s Lake Opinicon (780 ha) indicates that the loss of just two additional adult female map or painted turtles per year will lead to population extinction within 300-350 years. Such slow population declines are difficult to detect but can be avoided by the introduction of effective bycatch reduction programmes (e.g., mandatory exclusion devices and changes to fishing seasons).

Reference: Midwood, J.D. 2015. Bycatch mortality can cause extirpation in four freshwater turtle species Aquatic Conservation: Marine & Freshwater Ecosystems. 25, 71–80.