Monday, July 27, 2009

460A is Finally a Daddy!

The last two weeks at the Audubon Center at Francis Beidler Forest have been filled with summer camp, so the blog has not been updated as frequently as we would like.

With time now available, we would like to update you on some of the stories from this first year of Project PROTHO. The season is rapidly drawing to a close and the Prothonotary Warblers (Protonotaria citrea) of Beidler Forest will be migrating south to their wintering ground in Central America and northern South America. Stay tuned...with the birds now banded, we may find out exactly where on the planet the Beidler Forest Prothonotary Warblers spend the winter.

Previous blog entries highlighted the banding of 460A (March 31, 2009 & April 9, 2009) and his subsequent shift toward the less-desirable territory at the edge of the swamp. The map image shows several territories with 460A's being the bright yellow near the first fork along the boardwalk. His territory expanded slightly during the season. 460A was almost always the first Prothonotary Warbler visitors would encounter. He would come close to the boardwalk and seemed to always be singing. We commented that with all the effort 460A was investing in the breeding ritual, despite his less-than-stellar territory, he should have attracted at least one female. As other Prothonotary Warbler pairs were taking their fledglings out of the swamp to the habitat of the adjoining higher ground, it appeared that 460A would end the breeding season alone. Not surprisingly, we were wrong.

Although other pairs began the process of reproducing their species earlier than 460A, many of those nests failed or fledged fewer chicks than were hatched. Some of the attrition was due to predation, but some was the result of parasitism in the form of a Brown-headed Cowbird chick (see story here). The Cornell Lab of Ornithology has published an article on why some songbirds may tolerate cowbird chicks in their nests, "Extortion Rackets and Egg-Farming by Cowbirds."

In the end, 460A found a mate and they made a nest behind the interpretive sign at #3. Three chicks hatched and were banded once their legs had reached their adult size. Observers have seen the parents feeding two of the fledglings, including caterpillars found hidden within curled, brown leaves.

We look forward to next spring and the return of the banded Prothonotary Warblers. What else will they be able to teach us?

Images by Mark Musselman

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