Entangled seabird and marine mammal reports from citizen science surveys from coastal California (1997-2017).

Marine fauna in the California Current System is susceptible to entanglement in anthropogenic debris. We examined beach survey data from six California counties to describe trends of entangled marine birds and mammals (1997-2017). Surveyors reported 357 cases of entanglements among 65,604 carcasses. Monterey County had the greatest average entanglement rate (0.007) of surveyed counties, however, was not statistically different from Santa Cruz (p > 0.05). Twenty-six seabird species (97%) and three marine mammal species (3%), and three non-marine birds were affected. Numerically, Common Murre (23%), Brandt's Cormorant (13%), Western Gull (9.6%), Sooty Shearwater (8%) and Brown Pelican (7%) were the most affected due to abundance, but their entanglement rates were not statistically different (p > 0.05). The most vulnerable species were those frequently documented as entanglement despite low deposition numbers (Merganser spp. 25%). Entangling material consisted primarily of monofilament line (some hooks/lures), but other entanglement items were reported.

Prey and plastic ingestion of Pacific Northern Fulmars (Fulmarus glacialis rogersii) from Monterey Bay, California.

Marine plastic pollution affects seabirds, including Pacific Northern Fulmars (Fulmarus glacialis rodgersii), that feed at the surface and mistake plastic for prey or incidentally ingest it. Direct and indirect health issues can result, including satiety and possibly leading to inefficient foraging. Our objective was to examine fulmar body condition, identify cephalopod diet to species, enumerate and weigh ingested plastic, and determine if prey number and size were correlated with ingested plastics in beach-cast fulmars wintering in Monterey Bay California (2003, n=178: 2007, n=185). Fulmars consumed mostly Gonatus pyros, G. onyx, and G. californiensis of similar size for both years. We found a significant negative correlation between pectoral muscle index and average size of cephalopod beaks per stomach; a significant increase in plastic categories between 2003 and 2007; and no significant correlation between number and mass of plastic compared with number and size of prey for either year.