British Columbia Marbled Murrelet Occupied Detection Surveys: Digital dataset

This data set contains the most complete known Marbled Murrelet occupancy
detections at inland stations at georeferenced locations throughout British
Columbia. Detection information includes total number of detections, total
number of audio, visual, audio and visual, and total occupied detections. When
more than one survey took place at a particular station, the survey information
is summed for a total detection. Summation can occur within years, or across
years. The number of surveys conducted, and the years the surveys took place
will be noted when available.

This database is a compilation of many sources and “occupied detection” is in
some cases defined by the original scientists. Otherwise protocol is set by
the Pacific Seabird Group (2000) as 1) Birds flying below canopy, through,
into, or out of forest canopy, 2) Birds perching, landing, or attempting to
land, or 3) Birds calling from a stationary position. A call is stationary
when more than 3 calls are heard.