Nature Oddities - Those Insidious Cowbirds

Back in the early part of spring, my friend and I watched as a pair of Common Yellowthroats were obviously building a nest. We watched them flying in and out of a blackberry patch bringing in nesting material. A week or so later when in the same area, we witnessed a pair of Brown-headed Cowbirds lurking about watching. My friend commented potential trouble.

More truthful words had never been spoken. Today I watched in amazement at the result of what happens when a nest has been parasitized. I stood for at least 45 minutes and watched the spectacle. What caught my attention was the considerable size difference. The fledgling Cowbird is twice the size of the Yellowthroat. What an absolute bizarre sight. A fledging Yellowthroat was also nearby but got no attention.

The adult Yellowthroat was working tirelessly trying to feed this young Cowbird whose appetite seemed endless and stomach bottomless. On a few occasions it would stop short trying to get the fledging Cowbird to move. It however was pefectly content to sit and wait for food to appear. There was the occasional preening to remove molting feathers and a stretch every now and then but would soon settle back down resting on the branch.

During one of the extended hunting trips by the Yellowthroat, the fledgling Cowbird stood up looking about then started makings its little pitty calls and ruffling wings. The term slothenly came to mind. This shot gives a good prespective and how large the young Cowbird is.

As it appeared it would be an all day feeding event, I took my leave. Whether it is imprinting or some other unknown connection of nature, it surprises me that the adult Yellowthroat continued to feed such a large bird leaving its on species off-spring to fend for itself. You would think that something in nature would signal that this is a bird of a different feather. I guess that instinct to feed when a mouth is gapping open is just too great.