2023 was an exciting year for Common Terns at Presqu’ile Provincial Park. Since 2013, when we started novel management to exclude predators from protected tern breeding areas, this declining colony has stabilized and begun to increase, even in the face of challenges from record high-water levels in Lake Ontario. Over the last three years, this management success has led to a dramatic increase in the size of the tern colony.
The 2023 breeding season built on this success, with 340 nests laid (over twice the number laid last year) and a record number of fledglings leaving the colony (> 400 chicks) despite some predation by a mink late in the season. We collaborated with park staff to implement social attraction systems, colony surveillance methods, and monitor all nests, eggs, and chicks in the colony. We provided advice as park staff expanded protected areas by over 60%, providing a total of 390 m2 of protected area (sufficient for ~400 or more nests). To inform future management approaches, we continued long-term demographic studies (to assess immigration and recruitment), examined tern diets using genetic techniques, and explored acoustic methods for colony monitoring.
We are optimistic that future years will bring continued success for conservation and restoration work at Presqu’ile and are grateful, as always, for the Friends’ continuing support of these efforts to restore this regionally declining species.