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Iowa 1985-1990 (pending review)


General Methods
Sampling & coverage of blocks

Iowa was divided into approximately 6mi x 6mi townships based on the old township-range system. Each township was then divided into four 3mi x 3mi quarter blocks. The southeast quarter of every other township was designated as a standard block. Priority blocks were selected based on their unique or representative natural features; every county had at least one priority block. ("Standard" and "priority" blocks in Iowa BBA are respectively treated as "priority" and "non-priority" blocks in our website to match our definitions.)

View blocks in the Mapping Tool >>

Coordination of coverage
Management of this project was accomplished with the help of volunteers from Iowa's birding community, IDNR personnel, and individuals from other natural resource agencies. Regional coordinators were found to be inactive.

Breeding Evidence Codes
Code Code description  (see handbook for full description & use suggestions)
OB Category - Observed: not breeding evidence
O Species (male or female) observed in a block during its breeding season with no evidence of breeding. Not in suitable nesting habitat. Includes species such as vultures or raptors flying over, or a colonial nesting species not at a nesting colony.
PO Category - possible breeding evidence
H Species observed in suitable nesting habitat during its breeding season.
X Singing male present in suitable nesting habitat during its breeding season.
PR Category - probable breeding evidence
P Pair observed in suitable nesting habitat during its breeding season.
T Permanent territory presumed through defense of territory (e.g. chasing individuals of the same species).
C Courtship behavior or copulation.
N Visiting probable nest site.
A Agitated behavior or anxiety calls from adult.
B Nest building by wrens or excavation of holes by woodpeckers.
M 7 or more singing or territorial birds of a species detected within a block on one day.
CO Category - confirmed evidence of breeding
NB Nest building at the actual nest site.
PE Physiological evidence of breeding, e.g. highly vascularized, edematous brood patch or egg in oviduct based on bird in hand. (For banders.)
DD Distraction display or injury feigning.
UN Used nests or egg shells found. Must be carefully identified, if they are to be accepted.
FL Recently fledged young (either precocial or altricial) incapable of sustained flight, restricted to natal area by dependence on adults or limited mobility.
ON Adults entering or leaving a nest site in circumstances indicating occupied nest. To be used for nests which are too high (e.g. the tops of trees) or enclosed (e.g. chimneys) for the contents to be seen.
AY Attending young: adult carrying fecal sac or food for young; not used for terns or Osprey.
NE Nest with egg(s).
NY Nest with young seen or heard.
Habitat Codes
- - this atlas does not record habitat on the field card - -

Where this information came from
Most of the information on this page is from the project's publication or Handbook (guide for field work).
U.S. Department of the Interior || U.S. Geological Survey || Patuxent Wildlife Research Center  Laurel, MD, USA 20708-4038
This site is:
Information contained in this application does not necessarily have the endorsement of USGS.

Last updated: Site - May 2014; Content - various, depending on atlas.
Page generated on: 24-Jan-2018