Sunday, July 1, 2012

Killdeer Nests or Non-nests, such as they are.


Killdeer eggs lying on the ground next to the driveway of my Sister and Brother-in-Law in Paris, Texas; 6/22/2011.
The past couple of posts this weekend have dealt with nesting habits of some birds: Friday - "The Nestbuilders" and Saturday - "birds that use man-made structures." Then there is the famous Killdeer which won't build any nest at all, nor will it use human constructed structures  Instead it lays its eggs on the bare ground, usually in an open grassy or gravelly area which has an environment where the eggs will be almost invisible, surrounded by pebbles, cinders, gravel, twigs, etc. It finds a small depression in the ground or might even scrape a very shallow hollow. Their eggs (Above) have a lot of brownish blotches and spots on a buffy background, perfect for blending in with its background. Killdeers will lay their eggs in such places as on the edges of parking lots, on the sides of roads or driveways ( as in the case Above), and on grassy pebbly beaches. When I visited my Sister and her husband in Texas last summer, Dan, my Brother-in-Law, told me that a pair of Killdeers layed eggs on the gravel of his driveway. He said he had to put a small log next to the nest (I mean eggs) so they wouldn't accidently run over them with their vehicles. As visible as the eggs are in the photo (Above), it took me quite a while to find them, even after Dan gave me a detailed description of where I would find them. They were hidden very well in broad daylight. 
A Killdeer feigning its broken wing routine, Olsen Lake, Rock Cut State Park; 5/5/2012.
The same Killdeer pretending to be prey,  Olsen Lake, Rock Cut State Park; 5/5/2012.
This Spring, while scanning Olsen Lake for water birds, there was quite a commotion inside the fence that bordered the beach. Two Killdeers were screaming their very loud and familiar and incessant "kill-deer - kill-deer - kill-deer..." call. One of the pair would fly away, then come back hop around the ground, fly away again, and repeat this several times. The other Killdeer put on its "broken-wing" display (Above). I knew then there was a nest (umm ...I mean eggs) on the ground somewhere on the other side of the fence. When a Killdeer feels that danger (me in this case) has approached too close to their eggs, it will put on a display in which it pretends it has a broken wing; therefore, offerring itself up as prey to the encroaching enemy. The idea is that predators will tend to go after the weakest link of a herd. So if I was the predator, I would then follow the "injured" Killdeer, beacuse it will be an easy prey, whose aim is to protect the eggs by leading me away from where the eggs lie. Of course, I hadn't any intention to follow the Killdeer and I certainly was not about to climb or leap over the chest high fence to get to them. This confused the Killdeer, and it would switch from its "broken-wing display" to running normal, then going back to its "act." It did this several times before it decided I was not  danger. I likewise decided I had better leave before it exhausted itself.

Below is a link to a video I found on youtube that does a good job showing how well the eggs and the bird are camouflaged by the surroundings and a nice example of the "broken-wing display" behavior.

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