USDA Forest Service
 

Pacific Southwest Research Station

 

Pacific Southwest Research Station
800 Buchanan Street
Albany, CA 94710-0011

(510) 559-6300

United States Department of Agriculture Forest Service. USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.

Research TopicsWildlife & Fish: Bird Monitoring

Offshore Monitoring Methods for Marbled Murrelets

Marbled Murrelet, breeding plumage. Photo: Copyright Ron LeValleyThe Marbled Murrelet is elusive in its terrestrial environment, and offshore monitoring has been determined to be the best method to monitor the population (Madsen et al 1999). We started surveying Marbled Murrelets in the marine environment in 1989. We have used both land-based and offshore monitoring, eventually focusing on and refining offshore survey methods.

In 2000, we worked with the Northwest Forest Plan Marbled Murrelet Monitoring Team (the Team) to develop the current offshore protocol (see Raphael et al. 2007). It is designed to monitor population estimates and trends with a standardized sampling design in California, Oregon, and Washington.

We are now working to incorporate our earlier offshore surveys (1989-1999) with the new survey design, in order to assess long-term trends of the murrelet population in northern California and southern Oregon.

Reproductive success is also best monitored at sea, as murrelet nests are difficult to find. In 1993, we developed methods to monitor productivity using offshore surveys (Ralph and Long 1995) and are working with the Team to standardize methods across their range. We are currently looking at differences in distribution between adult and juvenile murrelets at sea based on distance from shore (reflecting differences in water depth), habitat, and other factors.

Publications
  • Ralph, C.J., G. Hunt, J. Piatt, and M. Raphael (Eds.). 1995. Ecology and conservation of the Marbled Murrelet. Gen. Tech. Rep. PSW-GTR-152. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture. 420 pp.
  • Strachan, G., M. McAllister, and C.J. Ralph. 1995. Marbled Murrelet at-sea and foraging behavior. pp. 117-128 in Ecology and Conservation of the Marbled Murrelet. Gen. Tech. Rep. PSW-GTR-152. Albany, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture.

Population monitoring

Productivity monitoringMarbled Murrelet chick on the forest floor

Additional publications can be found in our Publications List .

Last modified by L.L. Long

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Last Modified: Mar 28, 2013 03:37:34 PM