Bird Nest Predation
On the 18th of April, a pair of Northern Cardinals
selected a nest site near the top of a dense, 8 foot holly tree, a
foundation planting that obscures about 1/4 of our open front porch.
They located the nest under the overhang of the roof, facing our front
door. By the 21st, a clutch of three eggs had been laid and Mrs. C began
to sit on the nest. We succeeded at keeping a low profile, despite the
near proximity to our main entrance. She was relaxed and seemingly
unworried by our quiet comings and goings. Yesterday morning, all was
well, but sometime around midday, after almost a week of incubation, all
three eggs and, it appears, Mrs. C, vanished without a trace!
There is no obvious disturbance or damage to the nest or the immediate
area. The interior of the nest is pristine ~ no feathers, eggshell bits,
membrane material. Cats are rarely a problem. In addition to the typical
Blue Jays and Crows, we have a lot of squirrels, raccoons, opossums,
skunks and even a pair of red-tail hawks on our wooded acre and the
surrounds. Due to, I believe, some nearby housing construction, I have
observed a opossum during the day several times this past week and have
noticed a new arrival, a woodchuck. With temperatures in the 50's, I
think it is too chilly for snakes to be active. What would be your best
guess as to what
happened? Any chance the pair will return to the same nest and try again?
There are so many potential predators that it is hard to say. Probably
raccoons or opossums. They often will carry off the eggs. Cardinals nest
fairly close to the ground so even cats and dogs can be a
menace. Woodchucks or squirrels? No! They will not be interested, wrong
food. This probably happened at night.
Cardinals re-nest a number of times in a season. The pair in my backyard
was still feeding their own successful brood in mid September. Three of them!
There is no way to know for sure but the possum is an unlikey culprit,
woodchuck certainly not. Cats would be suspect, even if you don't regularly
see them, if the eggs had hatched, but I don't think a cat would take eggs.
Even with the cool temperatures a snake is a possibility, and they leave no
evidence. Crow is a good possibility, they often raid nests and might well
carry off the eggs without leaving any evidence behind. Blue jays could do
the same but are less likely to, being nearer the same size as the
cardinals. If this is the scenario then the female cardinal is probably
alive and well somewhere, and will most likely nest again, but not in the
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Update: June 2012