Boosting Recovery Of Endangered Piping Plovers With Predator Exclosures – WWF-Funded Success!
In May this year, WWF’s Director of Species Conservation, Pete Ewins, visited one of our Endangered Species Recovery Fund (ESRF) projects in Alberta. This project, studying piping plovers, is led by piping plover expert Lance Engley from the Alberta Conservation Association. On the day of Pete’s visit, the tiny lake east of Edmonton had six pairs of piping plovers already incubating eggs, or establishing territories along the sandy/gravel shorelines.
The piping plover has been listed as ‘endangered’ in Canada since 1985. In Alberta, the piping plover population has been surveyed thoroughly. Census results showed a population decline of 50 percent between 1986 and 2001. Research supported annually over the past 20 years by the WWF-administered ESRF has shown very clearly that predation of eggs is one of the biggest problems for the Great Plains/prairie population, limiting its recovery. Although few people have actually witnessed predation of plover eggs, through their research, field biologists know that the main egg predators are crows, gulls and mammals such as raccoons, fox, coyote and skunks.
The piping plover has been listed as ‘endangered’ in Canada since 1985. In Alberta, the piping plover population has been surveyed thoroughly. Census results showed a population decline of 50 percent between 1986 and 2001. Research supported annually over the past 20 years by the WWF-administered ESRF has shown very clearly that predation of eggs is one of the biggest problems for the Great Plains/prairie population, limiting its recovery. Although few people have actually witnessed predation of plover eggs, through their research, field biologists know that the main egg predators are crows, gulls and mammals such as raccoons, fox, coyote and skunks.
Piping plover (Charadrius melodus), Canada
Since 2002, around the fringes of shallow saline nesting lakes in Alberta, a dedicated team of field biologists, often working with local landowners, have installed predator exclosures around as many nests as possible to increase nesting success. These exclosures allow the piping plovers to enter the nest but exclude their predators. The incubating plover simply runs between the holes in the mesh of the exclosure, and is protected from most predators, since the cage is securely nailed down to the beach with 25 cm (10 inch) nails! By the end of May, Engley and his team would have all the active nests that Pete visited enclosed within predator exclosures.
Piping plover eggs and expert Lance Engley from the Alberta Conservation Association.
Initial trials found that the predator exclosures doubled nesting success, which led to the large scale management program in Alberta. Since 2001, the Alberta piping plover population has increased by over 95 percent, from 150 adults to the 295 adults counted in 2008! WWF-Canada, with the help of our supporters, is proud to have been a part of this species recovery success story.
This project does emphasize how long these efforts can take to succeed. It also demonstrates that in habitats that have become heavily fragmented and altered (such as Alberta’s agricultural areas) some predatory species can exert huge negative pressures on more specialized and sensitive wildlife.
This project does emphasize how long these efforts can take to succeed. It also demonstrates that in habitats that have become heavily fragmented and altered (such as Alberta’s agricultural areas) some predatory species can exert huge negative pressures on more specialized and sensitive wildlife.