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Marbled murrelet

Photo of Marbled Murrelet

Scientific name: Brachyramphus marmoratus


Critical Habitat: Designated

Listing: In 1992, the Washington, Oregon, and California population of the marbled murrelet was federally listed as threatened. See the ECOS website for current information, including Federal Register documents, recovery plan and other recovery documents, 5-year reviews, critical habitat designation, habitat conservation plans, safe harbor agreements, and petitions.

Potential Range Map for Oregon

  • Habitat

    The marbled murrelet is a small, robin-sized, diving seabird that feeds primarily on fish and invertebrates in near-shore marine waters. It spends the majority of its time on the ocean, resting and feeding, but comes inland up to 80 kilometers (50 miles) to nest in forest stands with old growth forest characteristics. These dense shady forests are generally characterized by large trees with large branches or deformities for use as nest platforms. Murrelets nest in stands varying in size from several acres to thousands of acres. However, larger, unfragmented stands of old growth appear to be the highest quality habitat for marbled murrelet nesting. Nesting stands are dominated by Douglas fir in Oregon and Washington and by old-growth redwoods in California.

    Life History

    Marbled murrelets nest in Oregon from mid-April to mid-September. The sexually mature adult murrelet (at age 2 or 3 of an average 15-year lifespan) generally lays a single egg on a mossy limb of an old-growth conifer tree. Both sexes incubate the egg in alternating 24-hour shifts for 30 days. Murrelet chicks are virtually helpless at hatching and rely on the adults for food. The adults feed the chick at least once per day, flying in (primarily at dawn and dusk) from feeding on the ocean, carrying one fish at a time. The young fledge from the nest in about 28 days and appear to fly directly to the sea upon leaving the nest. Marbled murrelets have a naturally low reproductive rate because they lay only one egg per nest and not all adults nest every year.

    Reasons for Decline

    The primary cause of marbled murrelet population decline is the loss and modification of nesting habitat in old growth and mature forests through commercial timber harvests, human-induced fires, and land conversions, and to a lesser degree, through natural causes such as wild fires and wind storms. In general, forest management practices that maximize timber production cut and replant forest stands every 40 to 60 years. Since it takes 100 to 250 years to grow marbled murrelet nesting habitat, this time frame frequently does not allow old-growth characteristics to develop, thus eliminating large areas from providing future nesting habitat. Continued harvest of old growth and mature forests also perpetuates the loss and fragmentation of remaining habitat. Changing the existing habitat by fragmenting the forest into small patches of suitable habitat surrounded by open space also affects the habitat quality. Increased forest fragmentation can reduce nesting success by allowing increased predation of nests by raptors (great horned owls, sharp-shinned hawks, peregrine falcons) and corvids (jays, ravens, crows). 

    Climate change is likely to exasperate the impacts of continued nesting habitat loss and fragmentation.  In particular, anthropogenic climate change has the potential to substantially affect the coast redwood forests in California and Oregon by the late 21st century, in which this forest type is projected to experience a reduction of nearly one fourth of its range.  

    Marine environment threats include Harmful Algal Blooms (HABs), prey availability, and oil spills, gill net fishing and climate change which is projected to result in changes throughout the marine food web, further reducing prey quality and quantity. 

    Conservation Measures

    Areas of critical habitat have been designated within the three-state area to protect habitat and promote the recovery of the species. These areas include approximately 3 million acres of federal lands and almost one million acres of state, county, city and private lands. Over the next 50 to 100 years, the protected areas on federal lands should provide for an increase in suitable nesting habitat. Although timber continues to be harvested, timber sale programs on federal lands require consultation with the U.S. Fish and Wildlife Service to review and assess the potential impacts of the timber harvests on the marbled murrelet. In 1997, the Fish and Wildlife Service approved a recovery plan for the marbled murrelet that specified actions necessary to halt the decline of the species in the three-state area.

    References and Links

    Regulatory Information

    Listing Status: U.S. Fish and Wildlife Service. 1992. Final rule listing the marbled murrelet as threatened. Federal Register 57:45328-45337. 

    Critical Habitat: U.S. Fish and Wildlife Service. 1996. Final designation of critical habitat for the marbled murrelet. Federal Register 61:26256-26320. 

    Economic Analysis : U.S. Fish and Wildlife Service. 2007. Draft Economic Analysis of Critical Habitat Designation for the Marbled Murrelet. Report.; Federal Register 72:35025-35028. 

    Recovery Plan: U.S. Fish and Wildlife Service. 1997. Recovery Plan for the threatened marbled murrelet (Brachyramphus marmoratus) in Washington, Oregon and California. Portland, Oregon. 203 pp.

    Federal Register Documents: Listing Status, Regulatory documents, current recovery plan, other recovery documents, Critical Habitat. View documents

    Conservation Plans, Safe Harbor Agreements, Petitions.

    Status Reviews and Other Reports

    Assessment through 1995: Ralph, C.J., G. L. Hunt, Jr., M. G. Raphael, and J. F. Piatt, (Technical Editors). 1995. Ecology and Conservation of the Marbled Murrelet. General Technical Report PSW-GTR-152, Pacific Southwest Research Station, U.S.D.A. Forest Service, Albany, CA 

    10-Year Report: Northwest Forest Plan—The first 10 years (1994-2003): status and trends of populations and nesting habitat for the marbled murrelet. 

    15-Year Report: Northwest Forest Plan—the first 15 years (1994–2008): status and trend of marbled murrelet populations and nesting habitat.

    20-Year Report: Northwest Forest Plan—the first 20 years (1994–2013): status and trend of marbled murrelet populations and nesting habitat.

    5-Year Status Review: U.S. Fish and Wildlife Service. 2009. Final 2009 5-Year Status Review for the Marbled Murrelet.

    5-Year Status Review: U.S. Fish and Wildlife Service. 2019. Final 2019 5-Year Status Review for the Marbled Murrelet. 

    Synthesis of science to inform land management within the Northwest Forest Plan area. Gen. Tech. Rep. PNW-GTR-966. Chapter 5: Marbled Murrelet.

    Alaska and British Columbia: Status Review of the Marbled Murrelet (Brachyramphus marmoratus) in Alaska and British Columbia. USGS 2006. Abstract; Download Report

    Survey Protocols

    Inland Survey Protocol: Methods for Surveying Marbled Murrelets in Forests: A Revised Protocol for Land Management and Research. January 2003. 

    Other Marbled Murrelet Websites

    U.S. Geological Survey: Patuxent Bird Identification Center 
    Northwest Forest Plan Information

    Oregon State University Oregon Murrelet Project

    Cornell Lab of Ornithology - All about Birds - Marbled Murrelet

    Regional Ecosystem Office: Northwest Forest Plan Website 

    USDA Forest Service, Pacific Region: Northwest Forest Plan Website


    Last updated: January 6, 2020

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