Abstract
Common Tern (Sterna hirundo) breeding populations in inland areas of North America have experienced significant declines, particularly in the Canadian waters of the lower Great Lakes. Once home to two-thirds of the Great Lakes population, Presqu’ile Provincial Park maintained only a small breeding colony of Common Terns from the 1970s to the early 2010s. In 2008, a research program was started to understand the population status of this colony. This involved close collaboration between faculty at Penn State University and Ontario Parks staff, and identified poor reproductive success at this site. Although many factors contributed to this poor reproductive success for terns at this colony, regular nest predation in June and July by Black-crowned Night Herons (Nycticorax nycticorax) appeared to be pushing this colony towards abandonment. Based on this finding, innovative management began in 2013 with the development and implementation of predator exclusion grids. These structures are designed to eliminate avian nest predation, as well as competition for nesting space from gulls. Although straightforward in concept, the success of predator exclusion grids for tern management requires careful implementation, attention to detail and timely responses based on regular monitoring. Here, we provide design and construction details, implementation requirements and discuss applicability for other tern colonies. We hope that this new tool allows managers to eliminate avian predation threats faced by Common Terns elsewhere in their range.
Creative Commons License
Recommended Citation
Arnold, Jennifer M.; Oswald, Stephen A.; Tyerman, Donald J.; and Barker, Michael J.
(2023)
"Predator Exclusion Grids Protect Common Terns from Avian Nest Predators at Presqu’ile Provincial Park, Lake Ontario,"
Ontario Birds: Vol. 41
:
Iss.
3
, Article 5.
Available at:
https://digitalcommons.usf.edu/ontario_birds/vol41/iss3/5