I did the math. Marbled Murrelet populations across their range have plummeted since 2004--from an estimated 947,500 to just over 365,000--yet this lower number isn't widely known. Why not?
I am not exactly sure, but I know this much: murrelets are notoriously difficult to survey, survey effort is not consistent across the bird's range (Alaska, British Columbia, Washington, Oregon, California), confidence intervals can be enormous and can make estimates look like guesswork. However, you cannot hide the downward trend here even if these estimates are a 100,000 birds off.
Sadly, it behooves some land-management agencies to use the higher estimate--close to a million murrelets--because it implies an abundant, healthy population of this imperiled seabird. It is much easier to let Alaska to log its Tongass National Forest or Washington its Olympic Peninsula rainforests, for instance, if we tell ourselves there are nearly a million murrelets on the Pacific Coast.
When the timber industry fought (again) to remove the Marbled Murrelet from the list of federally endangered species in 2008, they lost their case in the U.S. Court of Appeals in 2015 in part because because of the documented differences in how murrelets are managed between the U.S. and British Columbia. Underlying this decision, however, was the knowledge of the precipitous decline of murrelets in Alaska where most of the murrelet population occurs (but where they do not receive protection under the U.S. Endangered Species Act).
We can no longer depend on Alaska to serve as the great sanctuary for Marbled Murrelets. We cannot develop conservation strategies for this species if we believe (or want to believe) that there are "enough" murrelets in Alaska and British Columbia. Scientists have documented distinct populations of the Marbled Murrelet across its range. We need to protect all of these populations to preserve genetic diversity and resilience of this species.
In Washington state, where I live, Marbled Murrelet populations are carefully monitored under the Northwest Forest Plan. The latest report shows a strongly negative population trend from 2000-2013 of -4.6% at the state scale. Over this same period, a decline of -3.9% was observed in the Strait of Juan de Fuca and San Juan Islands (Conservation Zone 1) and a -6.7% decline on Washington's Outer Coast (Conservation Zone 2).
Clearly, we are not doing enough to save the Marbled Murrelet from extinction. We need to do more, better, sooner.
The first--and perhaps most difficult step is to remove the beautiful image of a million murrelets from your imagination.
Sources for population data:
WA-OR-CA: G. Falxa, M. Raphael. The Northwest Forest Plan—The First Twenty Years (1994-20013) Status and Trends of Marbled Murrelet Populations and Nesting Habitat.
BC:.Environment Canada. 2014. Recovery Strategy for the Marbled Murrelet (Brachyramphus marmoratus) in Canada. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa. v + 49 pp.
Alaska: Piatt, J.F., Kuletz, K.J., Burger, A.E., Hatch, S.A., Friesen, V.L., Birt, T.P. , Arimitsu, M.L., Drew, G.S., Harding, A.M.A., and K.S. Bixler, 2007, Status review of the Marbled Murrelet (Brachyramphus marmoratus) in Alaska and British Columbia: U.S. Geological Survey Open-File Report 2006-1387, 258 p.