Alberta Piping Plover Predator Exclosure and Population Monitoring Program 2005
Author(s)
Roy Schmelzeisen, Lance Engley, Amanda Rezansoff and Dave Prescott
Summary
Nest predation continues to be a significant limiting factor to the Great Plains piping plover population. Previous studies conducted in east-central Alberta and in the United States have shown that the use of predator exclosures can significantly reduce piping plover nest predation. Since 2002, predator exclosures have been applied to as many nests as possible in Alberta with the goal of increasing nest success and ultimately enhancing fledging success.
As a part of this program, annual surveys are conducted on core breeding lakes in order to better gauge population numbers and movement. These surveys complement the International Census conducted every five years across North America and are designed to monitor changes in populations and distribution. They also provide researchers with an opportunity to re-sight piping plovers banded in Alberta in previous years, as well as those banded in other jurisdictions. The information collected from band recoveries assists wildlife managers in determining dispersal patterns as well as adult and juvenile survival and complements the banding program being undertaken in Saskatchewan.
Predator exclosures used during the 2005 field season followed the same specifications as the 2004 models (Engley et al. 2004). Both models were small, quick to apply and of a similar design, the only difference being that one design was prefabricated by a steel manufacturer and reinforced with 3/16 gauge steel. Both designs were initially topped with a 2 cm x 2 cm plastic mesh; however, other materials were applied in response to coyote attacks on exclosed nests in which the netting failed to prevent the coyotes from preying upon the eggs. These materials included a second layer of 2 cm x 2 cm plastic mesh, 1.25 cm x 1.25 cm hardware cloth, 1 cm x 1 cm steel mesh, or 5 cm x 5 cm stucco wire (the same material used to construct the sides).
A total of 119 nests were found in 2005. Of the 109 exclosed nests with known fate, apparent nest success was 85.3% (93/109). The fate of only one of 6 unexclosed nests was known and that nest was preyed upon. Mayfield nest success was calculated to be 38.3% for unexclosed nests and 77.3% for exclosed nests.
Population inventories were carried out on 28 waterbodies. In Alberta, a total of 206 adults were located on 22 different waterbodies and an additional 34 adults were seen on the adjacent lakes in Saskatchewan. Increased water levels led to a much higher number of birds on some lakes that have been dry for the past several years. Piping plovers were located on Mott Lake, on Canadian Forces Base Wainwright, for the first time. Fledging success was calculated to be 21.6% and we calculated that 0.74 chicks per pair were fledged in 2005.
All activities carried out during the course of this project were done in support of the “Alberta Piping Plover Recovery Plan 2005-2010”. In particular, these activities were conducted to address Section 8.2 Productivity Enhancement, Section 8.3 Information and Outreach and Section 8.4 Population Monitoring and Research of the Recovery Plan. Results from this project were presented at the fall 2005 Alberta Piping Plover Recovery Team meeting.