Bio tech Mary Anne has checked in with the most recent news from South Core Banks. The two satellite tracked oystercatchers, UP and CF7, have not had good luck this season, and good luck is necessary to hatch eggs and raise chicks when there are predators to contend with.
UP and his mate, UR, had lost their first nesting attempt when their lone chick disappeared a few weeks ago. However, they came back with a two-egg nest on June 2. However, this nest, too, was lost on June 18. Mary Anne found the empty scrape that morning. Thanks to recent rain, there were no visible tracks or any other indication of the cause of failure.
Meanwhile, CF7, which had lost both of her nests to raccoons, has been hanging out with a flock of other adult oystercatchers several miles from her territory. Since her mate is unbanded, she could have been with him. After they have failed to nest successfully, oystercatchers may continue to occupy and defend their territory, or they may abandon it altogether. Even if they stay on it, gradually, they lose interest.
CF7 is probably beginning to transition from a breeding “mood” to a migration and winter “mood.” Instead of being intolerant of any other oystercatchers besides her mate (and chicks, if she were to have any), she will prefer to spend time roosting with groups of other oystercatchers. These changes in behavior are determined by the birds’ hormone levels, which are probably influenced by the length of day, as well as the presence of young to care for.