GCBO Area Search Criteria
o The area search method does not attempt to follow fixed transects. It assumes that birds are censured on foot, not by automobile. The routes covered are often pre-existing trails or roads through the habitat. Surveys should last a minimum of one hour. Longer search times are permitted as long as the exact time spent is noted.
o Observers should proceed at a pace that allows them to detect and identify all or almost all birds encountered.
o The number of individuals for each species should be counted or estimated in the case that many individuals of a species are encountered.
o Observers should record the date, location, time at which the coverage begins and ends and estimate the distance covered. There is a place in eBird and on GCBO Field Cards to note the start time and duration of survey.
o Additionally, survey data will be more valuable if the number of observers and an estimate of the area covered are recorded.
o Additional information of interest (weather conditions, interesting behaviors, names of observers, etc.) can be recorded in the "comment" box in eBird or on the GCBO Field Card.
o Enter the data into eBird (http://www.ebird.org), Note that to enter the data yourself, you must have or create a username and password on eBird.
GCBO Banding Methodology
Any banding must be carried out by a licensed banding station at one of our Partner Sites. The primary data collected should be species, age and/or sex (if possible), and number of nets and net time. All recommendations suggested by Hussel and Ralph below, such as placement and number of nets, should be followed if possible.
Banding description and considerations (from Hussel and Ralph, 1998) :
Most standardized capture procedures will involve only the use of mist nets. However, Heligoland traps or other traps (including baited traps) could be used for the same purposes. The count of newly-arrived birds should be the capture rate (e.g. birds/net-hour) of newly captured individuals. Standardized capture can also be a component of an estimated total. While standardization of effort is very important, at some sites, such as some exposed coastal locations, it may be difficult to maintain an adequately standardized trapping or netting procedure, due to frequent adverse weather, wide fluctuations in bird numbers, and/or habitat changes. In these circumstances, we do not recommend banding captures as the only, independent count method, but they can still be used as a component of a daily estimated total and to determine age and sex composition of the population. To further standardization, net and trap sites should be clearly identified and marked and set in exactly the same positions each year, if at all possible. The array of nets and traps should allow the participants to visit them within 10-15 minutes when no birds are present. The number and types of nets and traps should remain constant from hour to hour and year to year, as these variables can affect capture totals. We suggest that bait not be used with a standardized Heligoland trap or mistnetting program, because it is difficult to use consistently and may influence stopover behavior of migrants. Unavoidable changes in position, number or type of nets or traps (e.g. dimensions, mesh size) should be documented. The nets and traps should be operated during the same number of hours during the same standard time period each day, starting at a constant clock time or at a constant time relative to sunrise. For monitoring nocturnal migrants, an early morning start at the same time relative to sunrise is preferred. Nonetheless, even during the standard period, the trapping or netting operation should be stopped if conditions arise that endanger the safety of the birds (e.g., severe weather, more birds captured than can be safely handled, predator problems). Non-standard opening and closure times of nets and traps should be recorded. Partial closure and opening of the array of nets and traps should be avoided whenever possible.
RECOMMENDED METHODS FOR MONITORING BIRD POPULATIONS BY COUNTING AND CAPTURE OF MIGRANTS by David J. T. Hussell, Ontario Ministry of Natural Resources, P.O. Box 5000, Maple, Ontario L6A 1S9, Canada, and Environment Canada (Ontario Region), 49 Camelot Drive, Nepean, Ontario K1A 0H3, Canada and C. John Ralph, U.S.D.A. Forest Service, Redwood Sciences Laboratory, 1700 Bayview Drive, Arcata, California 95521 U.S.A. for the Intensive Sites Technical Committee of the Migration Monitoring Council