Nest Monitoring Guidelines
You should make at least three observations per nest, including the final observation to determine the nest fate (whether the nest was successful).
The building and incubation stages are the most sensitive periods of the nest cycle. When birds are building, avoid the area immediately surrounding the nest. During incubation, visit the nest every three days. During the nestling stage, plan to visit the nest every two days.
Some questions can be answered far from the nest. Is the nest still being built? Is it still active? Have the eggs hatched (i.e., are adults carrying food to nestlings)? But most data relies on quick and careful nest visits at close range.
A nest is considered successful if it results in at least one fledgling, or young bird, of the same species.
How can I continue to monitor a nest during the building and incubation stages without disturbing the birds?
Nests should be avoided during nest building and the first few days of incubation. Use binoculars from a distance, or check the nest when adults are not present, such as when the female occasionally leaves the nest to feed.
Check nests in the afternoon. Do not check nests in the early morning, because most females lay their eggs in the morning. Eggs or young nestlings can also quickly become cold if left alone in the morning. Also avoid checking nests at or after dusk, because females may be returning to the nest for the night.
No, avoid touching nests, eggs and young.
No, do not approach nests when young are close to fledging (leaving the nest). Despite being quite mobile inside a nest, nestlings still may have to undergo significant development before being able to fledge. If young birds are disturbed during this stage, they may leave the nest prematurely unable to fly. Birds that fledge prematurely do not usually stay in the nest despite attempts to return them, which leaves them with little chance of surviving. Once the young birds are fully feathered, you can check the nest from a distance with binoculars to determine if the parents are still actively feeding the young.
Avoid nests during bad weather, because checking nests during this time can be very stressful for birds. If the weather is cold, damp or rainy, postpone checking the nest.
No, you should wait until you are at least about 30 feet (10 meters) from the nest before stopping to record data.
Be wary of nest predators, and do not approach a nest if you see one. Be sure dogs, cats, crows or jays are not following or watching you. Nest predators are everywhere.
Whenever possible, take a different route away from the nest site than the route you took to reach it. This will help you avoid leaving a dead-end trail to the nest. Walking a back-and-forth route leaves scent trails that predators can use to later find and disturb the nest.
Minimize disturbance and do not startle the parents as you approach, as this may cause eggs or young to be knocked out of the nest. The best time to quickly check a nest is when parents are absent. Wait a few minutes to see if adults leave the nest on their own before approaching. Sometimes, a short wait is all it takes.
Nest boxes should be lightly tapped first to allow the parent to slip away before you stare directly into the box. Use small mirrors attached to poles for nests that are out of reach.
Brood parasites rely on other birds to raise their young. Brown-headed cowbirds, a species common to all Nestwatch regions, lay their eggs in the nests of other birds. Those birds, called host species, then raise cowbird chicks as their own—often at the expense of the host's own offspring. Be mindful of the number of cowbird eggs or young you see when monitoring a nest. Cowbird young develop very quickly and usually crowd the host young.