Will checking nests increase the risk of predation?
Nest predation by crows, jays, chipmunks, weasels, squirrels, skunks, raccoons, snakes, small rodents, cats, and birds of prey is a common cause of nest failure. Observers often fear that increased predation may result from the observer leaving a track or scent-trail to nests. However, a two-year investigation of this possibility by the British Trust for Ornithology showed that nests visited frequently had similar success rates as other nests left undisturbed between laying and fledging. This finding has been supported by the consistency of the results obtained from different observers’ records. Predation in the absence of human involvement has also been demonstrated by searches of completely undisturbed areas late in the season. Such findings are consistent with the normal high annual mortality of songbirds species. However, you should still do your best to minimize bringing attention to the nest.