Population Density Marbled Murrelet
The marbled murrelet brachyramphus marmoratus is a small seabird from the north pacific.
Population density marbled murrelet. 2 marbled murrelet entanglements occur in pacific salmon gillnet fisheries in the salish sea marbled murrelet population in washington was in decline from 2001 2010 miller et al. Abstract the marbled murrelet brachyramphus marmoratus is federally threatened in part of its range in western north america information on density and productivity is important for managing populations. Within a single planning unit were averaged adjusting for survey effort to calculate the illustrated metric average density of marbled murrelet by planning unit. The distance from shore of the offshore boundary for the target population varied by zone and.
Our monitoring plan is specifically designed to estimate marbled murrelet density population size and population trend in each of five geographic areas con servation zones between the northern tip of washington state and san. Summary of estimated density and population rounded to nearest 100 birds of the marbled murrelet in all zones surveyed conservation zones 1 5 2001 2010. It nests in old growth forests or on the ground at higher latitudes where trees cannot grow. Its habit of nesting in trees was suspected but not documented until a tree climber found a chick in 1974 making it one of the.
Average estimated population density of marbled murrelet by primary sampling unit psu for oregon pacific region es gis september 15 2008 fy08 es mamu 0004 0 20 40 60 80 100 km 0 20 40 60 mi based upon at sea. The density values range from 0 01 birds per square kilometre to 3 300 birds per square kilometre with the vast majority of the. Washington marbled murrelet population density trend for 2001 2015 for zones 1 and 2 combined all marine waters of washington state 15 2015 marbled murrelet monitoring 1 in 1992 the marbled murrelet was listed as u s. At sea marbled murrelet population monitoring since 2000 wdfw has joined usda forest service pacific northwest research station u s.
Fish and wildlife service and other state federal and private researchers to participate in a program to estimate marbled murrelet population size and trends during the breeding season between san francisco bay and washington state. It is a member of the auk family. 2006 raphael et al. 2012 gillnet fishery catch effort has increased.