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Research Technical Report

Living Document is available here:

Coastal Ocean Mammal and Bird Education and Research Surveys (BeachCOMBERS), 1997–2017: Twenty Years of Monitoring the California Coast

Donnelly-Greenan, E., J. Harvey, A. DeVogelaere, H. Nevins, J. Lindsey, R. McMorran, J. Marek, C. Grant, M. Martin, S. Knaub, S.R. Benson, L. Chang, E.M. Phillips (created July 2019)

Living Document

SUMMARY (dated July 2019)

The Coastal Ocean Mammal and Bird Education and Research Surveys (BeachCOMBERS) program was created in 1997 with the objective to train citizen scientists to collect standardized scientific data within Monterey Bay National Marine Sanctuary (MBNMS). Since then, this citizen science program has greatly expanded: we have trained and coordinated more than 150 volunteers to monitor human and natural impacts to coastal wildlife by documenting the deposition of marine birds, mammals, and sea turtles from as far north as Santa Cruz County to as far south as Los Angeles County.

Program objectives are as follows: 1) obtain baseline information on rates of beach deposition of marine birds and mammals; 2) assess causes of seabird and marine mammal mortality; 3) assist resource management agencies in early detection of unusual rates of natural and anthropogenic mortality; 4) assess abundance of tar balls (oil patches) on beaches; 5) build a network of interacting citizens, scientists, and resource managers; and 6) disseminate related information to resources agencies, the public, and educational institutions.

BeachCOMBERS is a collaborative program that has successfully informed resource managers about wildlife impacts from anthropogenic and natural sources such as oil spills, starvation, fishery interactions, harmful algal blooms, plastic ingestion, and entanglements (e.g., Nevins and Harvey 2004, Jessup et al. 2009, Nevins et al. 2011, Donnelly-Greenan et al. 2014, Henkel et al. 2014, Donnelly et al. in prep). The program is a collaboration between Moss Landing Marine Laboratories (MLML), MBNMS, and other state and research institutions including the California Department of Fish and Wildlife (CDFW), US Geological Survey (USGS), and US Fish and Wildlife Service (USFWS) with the specific goal of using deposition of beach-cast carcasses as an index of sanctuary health (see Nevins et al. 2011).

When examining deposition data, the effects of mortality events can only be determined if adequate information on baseline deposition of beached organisms is available (Eguchi 2002, Nevins et al. 2011). Well-designed long-term beach monitoring programs provide consistent, reliable baseline data that can detect large-scale catastrophic events such as oil spills, but also can detect more subtle changes in environmental quality including increased frequency of harmful algal blooms and long-term chronic oiling, which may not be apparent with a short-term sampling design (Stenzel et al. 1988, Nur et al. 1997, Shumway et al. 2003). Between 1997 and 2007, we identified 28 unusual mortality events including 15 that were documented based on a significant increase in deposition greater than a baseline threshold level, and 13 other events where the main indicator was increased oiling (i.e., >2% of birds) or strandings of very rare species (Nevins et al. 2011). Several documented events were of regional significance occurring along the west coast of North America (e.g., 1997–1998 El Niño, 2003 Northern Fulmar die-off; Nevins et al. 2011).

With the completion of 20 years of survey data and additional surveyed beaches added, our goal was to reexamine trends over the geographic entirety of the program and to examine baseline data for the added survey areas (Santa Barbara through Los Angeles counties). Here, our objective is to provide an overview of carcass deposition trends, to identify species die-offs, examine oiled carcass baselines, and discuss the success of our citizen science program. Detailed review of entanglements, harmful algal bloom events, oiled birds and other events will be added to this report as supplementary scientific publications from our investigators and collaborators as they are produced and become available.