While working in a Lyme forest this past July I came upon a yellow-billed cuckoo incessantly belting its alarm call somewhere over my head. Thinking it was merely reacting to my presence, I proceeded on quickly to avoid causing any further disturbance. Roughly 15 minutes later I returned to the same area hearing the same noise- this time I looked up. I looked up and saw an eastern ratsnake slithering into the nest of a yellow-billed cuckoo who was perched several feet away scolding helplessly.
The photo is a bit dark, but you can see the snake (>4 ft in length) looped around in a heart shape with its head in the upper right, staring directly at my iPhone (note the white throat). The nest itself is loose assemblage of twigs, typical of the cuckoo, located approximately 15 feet off the forest floor in a small tree. I wasn't able to see if the snake had consumed any eggs or nestlings, but judging by the cuckoo's dedication to deterrence, it's likely that the snake was onto something. After the quick snapshot, I moved on to let the situation play out.
This was a first for me, and definitely an opportunistic moment as visual observations of nest depredation by snakes is a rare. Current research on the subject typically relies on video monitoring and/or telemetry of snakes to document these events in a systematic manner. The impact of nest depredation on bird populations or behavior likely varies drastically among habitats, landscape structures, and community assemblages (Cox 2012, Weatherhead 2010), making it difficult to draw general conclusions. Birds receive a great deal of our conservation efforts, and in the Northeast some populations may be negatively affected by nest depredation, but there are also several snake species of conservation concern (timber rattlesnake, smooth green snake, eastern hognose snake, eastern ribbon snake) that may rely on eggs and nestlings as a vital food source. 2013 is, after all, the Year of the Snake, not the year of the neotropical migrant...
This was a first for me, and definitely an opportunistic moment as visual observations of nest depredation by snakes is a rare. Current research on the subject typically relies on video monitoring and/or telemetry of snakes to document these events in a systematic manner. The impact of nest depredation on bird populations or behavior likely varies drastically among habitats, landscape structures, and community assemblages (Cox 2012, Weatherhead 2010), making it difficult to draw general conclusions. Birds receive a great deal of our conservation efforts, and in the Northeast some populations may be negatively affected by nest depredation, but there are also several snake species of conservation concern (timber rattlesnake, smooth green snake, eastern hognose snake, eastern ribbon snake) that may rely on eggs and nestlings as a vital food source. 2013 is, after all, the Year of the Snake, not the year of the neotropical migrant...