Debris carried on ocean currents washes up on shorelines all over the world. Not only is this human-generated problem unsightly, it is a major hazard to the marine environment and harmful to the animals who live and depend on the sea.
Here on Midway Atoll, marine debris is a problem that is visible on otherwise pristine white beaches; nets and other kinds of discarded materials wash up on shore in quantities of over 100 pounds per week. All of this debris is a major danger for sea animals such as endangered Hawaiian monk seals. However, creatures of the water are not the only animals affected by sea-borne trash; marine debris poses a threat to the health of the thousands of albatross chicks that hatch on Midway every year.
A Plastic Diet
Over eons of evolution, Laysan Albatrosses learned that they could eat just about anything that floated on the ocean. Adult albatrosses thrive on squid, fish and flying fish eggs, digesting everything except tough squid beaks and eye lenses, fish otoliths (ear bones), as well as other floating organic matter. When a mass of this tough material has accumulated in a bird's stomach, it is passed up the throat and back out into the environment in an oval package called a "bolus." This is much like the process in which an owl regurgitates indigestible mice bones in an owl pellet. Squid and fish are so nutritious that during the time when albatrosses are raising their chicks, an oily slurry of partially digested squid and fish can be fed directly to their young from the adults' open mouths.
In recent times, humans have added plastics to the albatrosses' menu. When foraging over the open ocean, adult albatrosses unknowingly consume floating plastic and return to feed it to their young. It is possible that albatrosses ingest so much plastic because of their habit of preying on the eggs of flying fish. Flying fish lay long strings of garnet-colored eggs and attach them to objects floating at sea. Up until the invention of plastic, the fish used floating bits of wood and pumice, but now these natural items are outnumbered by floating plastic pieces. As a result, adult albatrosses often take in plastic while gathering fish eggs. Laysan Albatrosses eat greater volumes and more varieties of plastics than any other seabirds. Plastics can comprise up to 50% of the indigestible material in an albatross' intestinal tract, leading to problems such as:
Plastic Cigarette Lighters
Anyone visiting Midway would notice the abundance of plastic lighters scattered amid the landscape. In a two-and-a-half month period, volunteers collected well over 1000 lighters while working on the atoll.
(cigarette lighters collected by volunteers; picture by D. Tsukayama)
The overwhelming majority of these lighters were collected in the interior of Sand Island, far from the shoreline. Therefore, it is logical to assume that these lighters were fed by albatross adults to their chicks while on nesting grounds. Lighters and other plastic are a common component of albatross boluses; some are found as dramatic evidence causing albatross death.
How can the Plastic Problem be solved?
We all live on planet Earth, our home in the cosmos. Ocean currents do not distinguish from which wharf or ship marine plastic originates. Cigarette lighters and other plastic wastes that are not properly disposed of have greater consequences than we might initially perceive. A cigarette lighter tossed overboard anywhere in the North Pacific can wind up in an albatross' stomach on Midway Atoll. Here are some ideas on how to solve the problem:
Ideas, photos, and cigarette lighters
were contributed by: Daniel Tsukayama, Barbara Mayer, Ralph
Wuscher, Suzie Rashkis, Greg Schubert, Alex Wollin, David
Liittschwager, Cindy Carlisle, Misty Niemeyer, Howard
Rhinehart, Michelle Caudle, Mark Defley, Nick Nicolle,
Rebecca Overfield, John Sprague, Barbara Johnson, Susan
Middleton, John Klavitter, Lynsey Clowers, Bailey Bodeen,
Tanzie Bodeen, and other volunteers at Midway Atoll
National Wildlife Refuge. Summer 2003 "Leave only
by B. Mayer)
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Mahalo to Kamehameha Schools for providing server support.
Ideas, photos, and cigarette lighters were contributed by:
Daniel Tsukayama, Barbara Mayer, Ralph Wuscher, Suzie Rashkis, Greg Schubert, Alex Wollin, David Liittschwager, Cindy Carlisle, Misty Niemeyer, Howard Rhinehart, Michelle Caudle, Mark Defley, Nick Nicolle, Rebecca Overfield, John Sprague, Barbara Johnson, Susan Middleton, John Klavitter, Lynsey Clowers, Bailey Bodeen, Tanzie Bodeen,
and other volunteers at Midway Atoll National Wildlife Refuge.
"Leave only footprints......"
(picture by B. Mayer)