Wednesday, August 10, 2011

Northern leopard frog conservation in Alberta, Canada


For the third consecutive year, Calgary Zoo Centre for Conservation Research (CCR) biologists are weaving through masses of giant cattail, boot-sucking sloughs and the occasional herd of cattle to gain a better understanding of northern leopard frog ecology in western Canada.

In the last three decades for unknown reasons, the leopard frog has been disappearing from Alberta and the Pacific Northwest. There is a real concern among conservationists that the decline in the west could be hinting at the beginning of a larger continental decline. Attempts to stop this trend have been unsuccessful and it is widely accepted that a better understanding of the ecology of this species is needed.


Using intensive fieldwork and highly focused science, CCR researchers have been surveying for leopard frogs through 69 wetland sites across 90,000 square kilometres of southern Alberta. As they are sparsely distributed over a broad geographical range, leopard frogs can be difficult to detect in some habitats, making accurate population counts difficult. The survey information and measurements on water, climatic conditions and vegetation will be used in a mathematical model to develop a new high accuracy survey technique. Development of such a methodology will be essential for establishing the relationship between factors such as disease prevalence, habitat loss and fragmentation, water quality and leopard frog demographic parameters in Alberta and western Canada.

Preliminary results suggest that one-off site surveys historically used to monitor frogs in Alberta are likely to miss many of the individuals that are present at those sites. Survey accuracy can be improved by avoiding strong winds, wind chill and cold temperatures which limit frog activity and affect their detectability.

The five year study will help determine whether and to what extent northern leopard frogs are declining in the province, identify key habitats, find the best conditions to survey in and determine the amount of management necessary to ensure their long term survival.


Images from the Calgary Zoo, Alberta Canada

For more news on the Calgary Zoo see http://www.calgaryzoo.org/#axzz1Ug05YIgB

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