Sampling Methods
Breeding Codes
Verification Form


    The Arkansas Audobon Society initiated the Arkansas Breeding Bird Atlas (ABBA) Project in 1994 for the purpose of developing a series of distributional maps for all species of birds that breed within the state.  Initial funding of the project came from the Arkansas Game and fish commission, the University of Arkansas, and the National Fish and Wildlife Foundation in Washington, D.C.  Data collection began in 1994.  Success of this project is dependant upon volunteers for data collection among the 875 total blocks within the state.


    The sampling unit is a 25km2 (9 square miles) block that has been randomly selected within each U.S. Geological Survey topographic map in Arkansas.  A total of 918 topographic maps cover the entire state of Arkansas, but 43 of these are more than 50% outside the state  and were deleted from the project.  That leaves a total of 875 blocks to be surveyed state-wide, which is about 12-15 blocks per county.
    Each volunteer receives an 8.5 by 11 inch copy of a map of a USGS quadrangle map with the location of the block clearly marked, and an 8.5 by 11 inch map of the plot itself.  Different classes of road types are shown on the maps, from interstates and state highways to dirt roads, logging roads, and roads on levees.  Major bodies of water are shown, as are major rivers and streams.  Cities and towns are also labeled.
    We would like to identify at least 75% of the possible breeding species within each survey block.  Blocks are considered complete when the target of 1/3 of the sightings in each of the three categories, i.e., 33% in possible, 33% in probable, 34% in confirmed.  The absolute number of hours necessary for completion of a block is difficult to estimate and will vary with habitat.  15 hours of observation with at least three visits is optimal for the "average" survey block.  The most important aspect of block coverage is not that every acre be surveyed, but rather that every habitat be surveyed at different times of day and at different times within the breeding season.

Breeding Codes(Possible, Probable, Confirmed)


    PO  -- The species is seen or heard within the safe dates, but not in appropriate breeding habitat.

    PX -- A species is seen or heard within the safe dates and is located within appropriate breeding habitat, but no   other information concerning breeding status was discovered.


    PS -- At least 7 singing individuals of a single species are located during a single visit within the safe dates.  This code assumes that singing birds within safe dates are either territorial or advertising for mates, but you have no further evidence to suggest this.

    PP -- A male and female which you assume to be paired are seen toogether within the safe dates, perhaps just foraging or resting.

    PT -- A male bird clearly showing territorial behavior within the safe dates,such as singing from the same perch on several different visits or aerial displays or chasing off intruding males.

    PC -- Courtship and/or copulation observed within the safe dates.

    PN -- To be used with hole nesting species where an individual repeatedly visits a possible nest site within the safe dates, but for which there is no other evidence of breeding.

    PA -- An individual or a pair appears very agitated, both in behavior and in alarm calls, within the safe dates.  This code should not be used for behavior that occurs in response to "pishing" or owl calls.

    PB -- Nest building by wrens and woodpeckers within the safe dates.  Both groups build dummy nests or roosting nests, whether they are mated or not.


    NB -- Nest building by species other than wrens and woodpeckers.

    BP -- Physiological evidence of breeding based on a brood patch.  Sometimes when a bird comes off the nest it will preen, and a clearly featherless area can be seen on its breast and/or belly.

    DD -- Distraction display.  Should only be used for a species which "injury feigning" is part of thee behavioral repertoire, for example Killdeer, Common Nighthawk, or Mourning Dove.

    UN -- Used nest found.

    FL -- Recently fledged young that are still dependent upon adults.  This requires that you see adults in attendance, either protecting or feeding the young.

    ON -- Occupied nest.

    FS -- Adult bird seen carrying a fecal sac.

    FY -- Adult with food for young.

    NE -- Nest found with eggs.

    NY -- Nest with young.


    A special thanks to all the volunteers that have put the time and effort in completing past and present atlas blocks.

This project is being coordinated by Kimberly G. Smith, Dept. of Biological Sciences, University of Arkansas.

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