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Instructions for Recording Data in the Field

Download the Project NestWatch code sheets

Please note that the field data sheets are for your use only
and should not be sent in to BSC.

The most important information to report about a nest is:

  1. The identity of the species;
  2. The nest location;
  3. Visit date and nest contents each time you check the nest.

This is the minimum data to collect for useful analysis. See below for further details on what information to collect and how to record it.

Key points to remember

  • Report every active nest. Information on failed nesting attempts is just as important as information on successful ones!
  • Each nest attempt counts for one record. If a nest was used twice in the same season by the same pair of birds, these are considered as two separate attempts. For the second attempt, make a note in the Comments section that the nest was used previously in the same nesting season.
  • If you are unsure of the species you have monitored, do not report any information.
  • If you have made unusual observations, please make a special note in the Comments section to emphasize that the entries are correct (e.g., if you have recorded an abnormally long incubation period, or a very early laying date).
  • If you find a nest of a poorly known species, a species outside its normal range, or the first record for a species in a particular region, good photographic evidence of the nest, adult, or both is encouraged! If you are unsure of the importance of a record, contact us for more information, preferably while the nest is still active.

General Information

Bird species name: Please identify the parents carefully. If you're a beginner, concentrate on common species that are easy to identify, such as American Robin and Tree Swallow. Only report nests for which you are certain of the species.

Nest label: If you're monitoring more than one nest, give each nest an individual identifier, such as a nest code or number.

Nest Location

If possible, record the exact coordinates of the nest, either in UTM (Universal Transverse Mercator) or latitude/longitude (degrees, minutes, seconds). If you have a GPS (Global Positioning System), this is the most precise way to tell us about the location of the nest (use the NAD83 datum). If you have access to a topographic map of your area, you can also calculate your UTM coordinates. If you don't have access to either method, you can find your approximate location by using the online mapping tool available on the data entry page, or simply provide the postal code of the area where the nest was located.

Nest Visit Information

Record the date, time, and number of eggs or young present on each nest visit. If you can't determine the number of eggs or young on some visits (e.g., an adult was sitting on the nest) do not guess the number - simply put a question mark (?) in the appropriate field(s). Make a note in the Comments explaining why you were unable to determine the number of eggs and/or young.

As some species lay eggs in nests of other species, you have space to enter information for the host and the parasite species separately. The host is the primary species occupying the nest; it is the one incubating the eggs and providing parental care. The parasite is the species that laid its eggs in the host's nest; it does not incubate eggs and does not provide parental care. If the nest you monitored contained one or more eggs or young of a parasite species, record the number of eggs or young in the appropriate fields. Record the species of parasite, if known. The most common parasite species in North America is the Brown-headed Cowbird.

Use the Visit Status Codes to describe the stage of development of the nest, eggs, and young, as well as the observed activities of the adults for each visit. Recording the state of growth of the young can be very valuable for estimating laying dates and/or the hatching date, especially if the nest was found at the nestling stage. For example, young American Robins hatch blind and mostly naked; they usually open their eyes at the age of five days. Recording the activity of adult birds can help determine the stage of the nest, particularly when the contents cannot be seen. For example, an adult sitting tight on the nest implies that the nest contains eggs and/or small young; adults regularly going to/from the nest with food implies that young are present.

Nest Outcome

Complete this section after the nesting attempt is finished. A nest is considered successful if at least one young fledges. Indicate with the Outcome Codes the best evidence you have that at least one young left the nest successfully, even if you are not sure they all made it. You can use two codes, if needed. If you indicate a failure, please enter the code corresponding to the stage when it occurred (E=egg, J=young, X=egg or young).

If the parents start a new clutch after a failed nesting attempt, this is considered a new nest and will require a new nest record. Make a note in the Comments section that this nest is a re-nest.

If you did not visit the nest until the end, or if you find an empty nest and cannot assess whether the attempt was successful or not, you should indicate that the outcome was Unknown. You may also sometimes have evidence that some young fledged while others did not (e.g., if some were dead in the nest). In this case you should indicate both a success and a failure code. If the nest also contained a Brown-headed Cowbird, use the Comments section to indicate which young fledged.

Nest Site Description

Nest site: Choose one category only for each of IN, ON, and UNDER. For example, if the nest was in a live tree, you would write A (live tree) in the box IN, and leave the other boxes blank. In some cases, you may need to use two or all three elements (e.g., nest located IN a hedgerow and UNDER a live tree). Mark any checkboxes that apply to the nest site itself. Also indicate the nest site type (unenclosed, ledge, nest box, etc.) and other relevant details about the nest. Unenclosed refers to any nest that is not in a cavity or nest box. If the bird uses another bird or mammal's nest, please give details of the species, if known, in the Comments section. If you are not sure what to indicate in a section, you can leave it blank.

Exposure: Estimate how well you think the nest is hidden from predators. Although this is a subjective measure, it is unlikely that one person's Well Hidden will be another's Exposed.

Slope: Indicate if the ground close to the nest you monitored, or the ground supporting the nest structure (e.g., a tree) was flat or sloped or vertical (i.e., a cliff).

Direction of slope (aspect) and direction of nest hole: If you reported that the ground was sloped, indicate the direction in which the slope was facing. The direction of the slope is defined by the direction you are facing when walking towards the bottom of the slope. Similarly, if the nest was in a natural cavity or a nest box, indicate the direction the entrance is facing.

Nest height above ground / water: Record nest height to the nearest 0.1m if below one metre, and as accurately as possible if above one metre. Please give figures to one decimal place. If the nest is on the ground, on a sloping bank or in a ditch, give the height as 0m (zero). In cases where the nest is in a bush in a ditch, give the height to the base of the bush and not to the bottom of the ditch. If the nest is that of a ground nesting species, please always write a zero rather than leaving a blank space.

Habitat Description

For Simplified data entry:

The habitat is the area immediately surrounding the nest. Each habitat is described by a class (e.g., woodland, human sites, etc.) and a sub-class (e.g., the sub-class options for woodland habitat are: deciduous, coniferous, or mixed woodland). If no sub-class applies, use zero (0) for Undefined.

Example: If you find an American Robin nesting in one of the cedars behind your house, you would indicate: Class: D. Human sites and Sub-class: 1. Urban. In the Comments section, you can write that the tree supporting the nest was a cedar.

For Advanced data entry:

In the advanced data entry option you can record two habitat types for each nest. The 1st habitat is the habitat containing the nest; the 2nd major habitat is the habitat within 100m of the nest.

Each habitat is described by a class and a sub-class, as in the simplified version, and you can also provide further details on the habitat using structure and modification descriptions.

Example: If you find a Barn Swallow nest in your boathouse at the cottage, the 1st habitat would be Class: D. Human sites and Sub-class: 2. Rural. You could then further describe the 1st habitat with structure and modification codes. Use 2nd habitat codes to describe the area around the boathouse. For example it might be Class: F. Wetlands with mainly open water; Sub-class: 3. Small lake; Structure: K. Mud shore; Modification: 7. Bordered by grassland/farmland.

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