December 1 marked the seasonal changing of the guard for PRBO Conservation Science biologists at the Farallon Islands National Wildlife Refuge. We set right to work monitoring survival, reproduction, and population growth of one of the most intensively studied northern elephant seal breeding colonies in the world.
On our first check of Sand Flat, we discovered an immature female elephant seal with a plastic strap (the kind used to bind stacks of newspapers) stuck tightly around her neck. The ring was cutting into her flesh, making a very nasty wound, choking her slowly and painfully, and ultimately would have resulted in her death. PRBO biologist Derek Lee fashioned a hook with a sharpened inner edge on a long pole, and was able to cut off the plastic strap. After four days she is still on the beach and her wound is healing nicely.
Although people think that plastic trash is going to the landfill, very often it washes out to sea and kills wildlife. About 80% of the plastic in the ocean has been transported from non-point source pollution from storm drains, creeks, rivers, streams and beaches into the ocean, where it becomes a threat to marine life. Clear plastic bags that look like jellyfish are eaten by endangered leatherback sea turtles. Albatrosses in the North Pacific (and other seabirds) feed small plastic items to their chicks, and they eventually die. Animals are entangled in plastic straps, rings, and nets, and either drown or slowly choke to death – we typically see at least a dozen ringnecked sea lions on the Farallones every year.
An enormous area twice the size of Texas that is covered with plastic debris swirls around the central Pacific Ocean, known as the Eastern Garbage Patch. There is also a smaller area off the coast of Japan known as the Western Garbage Patch. Areas in the oceans that concentrate plastic items and fragments can threaten thousands of seabirds, sea turtles, pinnipeds, and other marine animals. In fact, according to ecologist David Laist of the Marine Mammal Commission, plastics may kill as many marine mammals as oil spills, heavy metals, or other toxic materials.
Our incident on the Farallones serves as a reminder that vast amounts of plastic, which can persist up to 1,000 years, finds its way into our ocean and ends up having severe unintended consequences. This female elephant seal was lucky, but how many other marine animals are not? One way you can help is to reduce your own consumption of plastics, and to lobby your elected officials for local measures to control storm drain runoff.