Following the life of a nest is an enriching time of discovery that gives a participant the opportunity to make an important scientific contribution. At the same time it must be done very carefully. Please read the nest monitoring guidelines below. The guiding principle to responsible nest monitoring is conducting observations with as little disturbance as possible.
In short, nest monitoring tracks a nest attempt throughout portions or the entire cycle of building, laying, incubating, nestling, and fledgling stages. Several kinds of data are recorded including dates and numbers of eggs, nestlings, and fledglings. Data for at least three visit dates with associated information are required, including the final visit that determines nest fate. It is essential that a nest is monitored until its fate is known, whether it was predated, abandoned, or successful. A nest is considered successful if it produces at least one young of the same species. Nest fate is critical for determining how well bird populations are surviving. While the focal banding species are a higher priority, Nestwatch receives nest data on any species.
Nest monitoring closely follows activities prescribed on the nest data sheet which was provided for you during the backyard visit or can be downloaded here. Depending on when the nest was found within the cycle and whether the nest failed (e.g. predated, abandoned) will determine how much monitoring occurs.
Timing of the Nesting Season and Nest Monitoring
Since Nestwatch includes several geographic regions from Florida to Massachusetts, the nesting season can begin at different times of the year. In general, year-round resident birds (e.g. Chickadees, Carolina Wrens, Cardinals) will begin nesting about mid-March in the Southeast and about a month later in the Northeast. Long distance migratory birds (e.g. House Wrens, Gray Catbirds) begin nesting about one month later for each respective region (mid-April in the Southeast to mid-May in the Northeast).
It’s important to keep in mind that the majority of breeding bird species will attempt more than one nest per breeding season, particularly if earlier nest attempts fail. Any nest attempt can be monitored.
Generally, nests are built very quickly within two to three days. Eggs are then laid at the rate of one per day. Beginning the day before the last egg is laid, most songbirds will begin 11-14 days incubating. Most songbird eggs hatch within 24−48 hours of each other. Once hatching occurs, 10-18 days are needed depending on the species for nestlings to develop sufficiently before they can fledge. This Nest Cycle Guide outlines the duration of incubation and nestling periods for Nestwatch focal species.
Nest Monitoring Guidelines
Nestwatch accepts nest data from any bird species. A nest does not have to be a species from our focal list.
Some questions can be answered far from the nest. For example, whether the nest is still being built, if it is still active, if eggs have hatched (i.e. if adults are carrying food to nestlings). But the most amount of data relies on quick and careful nest visits at close-range.
Avoid nests during nest building and the first few days of incubation. Use binoculars from a distance or check the nest when adults are not present, e.g., when the female occasionally leaves the nest to feed.
Do not check in the early morning. Check nests in the afternoon, since most females lay their eggs in the morning. Eggs and young nestlings get cold quickly if left alone in the morning.
Do not check nests at or after dusk. Females may be returning to the nest for the night.
Do not approach nests when young are close to fledging. When the young are disturbed during this stage, they may leave the nest prematurely. Young that fledge prematurely usually do not stay in the nest despite attempts to return them leaving them with little chance of survival. Once the young 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. If the weather is cold, damp, or rainy, postpone checking the nest until another day. Checking nests during this time can be very stressful for birds.
Be wary of nest predators. Be sure dogs, cats, crows, or jays are not following you or watching you. Nest predators are everywhere.
Do not leave a dead-end trail during nest-checking. Whenever possible, take a different route away from the nest site than the route you took to reach it. Walking a back-and forth route to the nest leaves a dead-end trail at the nest that can lead predators directly to the nest. Instead, make a loop to and from the nest.
Minimize disturbance at the nest. Do not startle parents on your approach the nest as this may cause eggs or young to get knocked out. Ideally, wait a few minutes to see if adults leave the nest on their own. The ideal time to quickly check a nest is when parents are absent. Sometimes waiting a short period of time for parents to leave 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. Avoid touching nests, eggs and young. Remember to wait until you are at least 10 meters from the nest before recording your field notes.
How often to visit a nest: The building and incubation stages are the most sensitive periods in the nest cycle. When birds are building avoid the area immediately around the nest. During incubation, visit the nest every three days. During the nestling stage, you can visit the nest every two days.
Follow the nest stage protocol above rigorously. Remember, make at least three observations per nest including the final one that determines nest fate.
Brood Parasitism. Brown-headed cowbirds, common to all Nestwatch regions, lay their eggs in the nests of other species. Host species raises cowbird chicks as their own most often at the expense of the host's offspring.
If you miss a day or can't determine the exact days of clutch completion or hatching it's OK. This is a learning process and nobody is perfect. If you have to be gone for an extended period, maybe ask a friend for help or contact us.