Surveys for Beached Marine Mammal and Seabird Carcasses: Annual Progress Report 2000

Holm, Greg

Excerpts: "Beached carcass surveys are performed to ascertain baseline information about seabird and marine mammal moratlity that occurs along the Redwood National and State Parks (RNSP) coastline. The main objectives of the surveys are to gather trend data on mortalities, and determine whether the mortalities resulted from natural or anthropogenic events. Documenting natural mortalities can help biologists monitor events such as the expected deaths of post-fledging and adult seabirds, fatal injuries from predation and other natural hazards, and diseases in a population. Also, the effects of natural events (e.g. El Nino) on a population could be monitored more effectively. The presence of petroleum products on carcasses can provide information on "background" levels of these contaminants in the marine system. In addition, baseline data on the presence of petroleum products on wildlife can be valuable for comparison when a large scale spill occurs. Entanglement in fishing gear and human trash, such as plastic bags and six-pack rings, has been documented as a cause of death for marine fauna and also needs to be monitored for frequency of occurrence within RNSP. Winter surveys (January, February, November, and December of 2000) were only conducted on Gold Bluffs Beach and Freshwater Spit, whereas all other surveys (March-October) were conducted on all 7 of the beach stretches. One hundred twenty three carcasses were detected [during the winter surveys]. Six hundred and ninety seven carcasses were detected [during the non-winter surveys]." Includes information on the species of seabirds and marine mammals detected and future survey recommendations. The appendices include maps of the beach stretches surveyed, RNSP beached carcass survey protocol, and a survey form.