Abstract
We reviewed medical records from select wildlife rehabilitation facilities in California to determine the prevalence of injury in California Brown Pelicans (Pelecanus occidentalis), gulls (Larus spp.), and pinniped species (Zalophus californianus, Mirounga angustirostris, and Phoca vitulina) due to fishing gear entanglement and ingestion from 2001 to 2006. Of 9,668 Brown Pelican, gull, and pinniped cases described during the 6-yr study period (2001–06), 1,090 (11.3%) were fishing gear–related. Pelican injuries caused by fishing gear were most common in the Monterey Bay region, where 59.6% of the pelicans rescued in this area and admitted to a rehabilitation center were injured by fishing gear over the 6-yr period. The highest prevalence of fishing gear–related injury in gulls was documented in the Los Angeles/Orange County region (16.1%), whereas the highest prevalences in pinnipeds were seen in the San Diego region (3.7%). Despite these higher prevalences of gull and pinniped fishing gear–related injuries in these specific regions, there was no statistical significance in these trends. Juvenile gulls and pinnipeds were more commonly injured by fishing gear than adults (gulls: P=0.03, odds ratio=1.29; pinnipeds: P=0.01, odds ratio=2.07). Male pinnipeds were twice as likely to be injured by fishing gear as females (P<0.01, odds ratio=2.19). The proportion of fishing gear–related injury cases that were successfully rehabilitated and released (percentage of cases successfully rehabilitated to the point of release out of the total number of fishing gear–related injury cases) was high in all three species groups (pelicans: 63%; gulls: 54%; pinnipeds: 70%). Fishing gear–related injuries in Brown Pelicans and gulls were highest in the fall, but there was only a significant difference between seasons for fishing gear–related injuries in pelicans. Fishing gear–related injuries in pinnipeds most commonly occurred in summer; however, a statistical difference was not detected between seasons for pinnipeds. Derelict fishing gear—lost, abandoned or discarded sport and commercial line, nets, traps, etc.—in the marine environment is a significant cause of injury in California coastal marine wildlife. We evaluated data for stranded animals only; our results may underestimate the true number of coastal marine animals injured by lost or discarded fishing gear in California.