Another entry in Abby’s Birdbrained Summer. Abby, the summer communication intern for the Coast Office of Audubon North Carolina, is visiting sites with Audubon’s field staff and our community of volunteers. After she goes into the field, she’ll post blogs detailing her experiences.
The south end of Wrightsville Beach has been a prime nesting site for shore birds since 2009. In 2009 and 2010, birds started breeding at Mason Inlet on the north end of the island, but relocated their colonies to the south when their original nests failed. They have been nesting on the south end without first trying at Mason Inlet since 2011. Currently, Audubon is monitoring nests of Least Terns, Common Terns, Black Skimmers, and American Oystercatchers within the posting. I went to monitor the nests with Lindsay Addison, the coastal biologist, and Carlie Thieman, a UNCW environmental studies student and Audubon intern.
The first thing I noticed within the posting was the noise. Black Skimmers sounded like dogs barking, and the Least Terns made their high-pitched calls. The birds thought we were intimidating, but crows are the biggest threat to the colonies on south Wrightsville Beach this year. Crows are notorious Least Tern egg-snatchers. When they come near, all the birds ascend from their nests in hopes of chasing away the predator. They are willing to sacrifice their nest for the good of the colony.
There had been heavy rainfall prior to the morning I went to monitor with Carlie and Lindsay. The Common Terns that nested on the apex of a dune had their nest washed away; their eggs rolled down the hill with the rain. When we got close to active nests, the Common Terns were not shy about protecting their eggs. Lindsay assured me that they would dive-bomb Carlie first, because they were familiar with her. Even if she changes her hat and clothing, the birds target her because she intrudes on their nests frequently. They don’t understand that productivity monitoring is in their best interest. Carlie has found fifteen Common Tern Nests in the posting this year.
The Black Skimmers reacted much differently than the terns. One limped around the beach and pretended to be injured, so a predator would go after the adult skimmer instead of its nest. The American Oystercatchers were very disturbed when we came near, and emitted a rapid piping. One pair employed the false brooding tactic; they sat down on the beach and pretended their nest was in a different location to draw the threat away from the actual nest. Lindsay guessed that the oystercatchers were acting so upset because they had a chick, and she was correct. We found the fluffy hatchling hiding in the grass on a dune. It was the first oystercatcher chick to hatch on Wrightsville Beach this summer, but it was not the last. The second south end pair's eggs hatched over Memorial Day Weekend.
