Sentinels of the Pacific: What Seabirds Tell Us about the Oil Industry

Sentinels of the Pacific: What Seabirds Tell Us about the Oil Industry
An oil-contaminated shearwater 09B-38379, banded 26 August 2017.Scott Simon

When ornithologist Hisashi Sugawa of the Bird Banding Association invited me this May to accompany his team to the ongoing investigation of the Streaked Shearwater (Calonectris leucomelas) on Kanmuri Island, an uninhabited island under the jurisdiction of Maizuru City in Kyoto Prefecture, I accepted with enthusiasm. This monitoring project, sponsored by the Maizuru Board of Education with the assistance of the Japan Maritime Self-Defense Force, has been ongoing since 1971. Due to the presence of the birds and the sensitive ecology, the island was declared a National Monument in 1924. Landing is prohibited except for scientific and religious purposes (there are three tiny Shinto shrines on the island). I hoped to learn more about the shearwaters and the ornithologists as part of my research on human–bird relations in the Western Pacific. I did not expect that the birds I encountered on this four-day trip would also present me with a lesson about the nature of the global economy.

According to the IUCN, the Streaked Shearwater has a global population of about 3,000,000 individuals and is thought to be decreasing. Every summer, they breed on the coast and offshore islands of Japan and Russia, as well as on islands of China, North Korea, and South Korea. During the winter, they migrate as far south as Australia and New Guinea. The IUCN Red Book lists shearwaters as near threatened, mostly due to threats from introduced rats and feral cats, but also due to fisheries bycatch. Radioactivity from the Fukushima nuclear accident may also have negatively impacted birds on Mikura Island.

Excellent photos and research data (in Japanese) can be found on the project website. I was amazed by the evening spectacle when shearwaters return to roost for the night. Thousands of them swoop across the horizon in behaviour called dynamic soaring. The birds fly against slower winds near the waves, gain altitude, catch stronger velocity winds, and then dive back to the sea. The Japanese name for the bird—oomizunagidori, meaning “the bird that scythes down the waters”—is derived from this flight. Just after sunset, thousands or more form dramatic “bird pillars” while swooping down to the island. Spending most of the night noisily courting, mating, and renovating burrows, they sleep for about three hours before diving off cliffs or trees to take flight before dawn. They assemble on the water in behaviour called ashiarai, or “foot washing,” before taking off to forage for fish and squid. Fishers appreciate them because they indicate spots where these catches can be found. Sugawa’s research shows that the birds have amazing breeding site fidelity, coming back to the same site within their colonies with about the same accuracy as Canadian humans coming back from Florida every spring.

In the evenings, the team caught birds in pre-defined transect squares near one of the shrines. If a bird already has a serially numbered metal ring on its leg, the number is dutifully recorded. If an un-ringed individual is caught, a ring is attached and the number noted. The birds are weighed and measured before being released. This research allows Sugawa and his colleagues to monitor the population and health of the colony. The oldest recorded shearwaters are at least 36 years old. They cannot know their age at the moment of banding, but the bands recorded date back to that time. Hardy birds indeed!

On the second morning, as the sun rose and the last stragglers emerged from the forest, Sugawa suddenly stopped to look carefully at one of the birds. On its breast and the top of its head were traces of a dirty, gummy substance. He examined it carefully, taking a sample and handing it over to a chemistry teacher for chemical analysis. This male bird measured 105.8mm (Total Head Length) and weighed 579 grams. Sugawa noted the possibility that it could have encountered pollution from the Iranian Sanchi oil tanker that sank off the coast of China on 14 January after colliding with a cargo ship and catching fire.

The CBC reported the spill in January as being “the size of Paris,” but little is known about its effects because it is a different kind of petroleum than that discharged in the Exxon Valdez and Deepwater Horizon disasters. Condensate, a by-product of natural gas production, does not clump into black globules that mire animals in muck. Nonetheless, experts are concerned that toxic condensate could contaminate fish destined for human consumption and note that birds are also at risk. Scientists at the UK National Oceanography Centre predicted that the spill could reach the southern shores of Honshu, and the Sea of Japan. Admittedly, only one bird out of 304 might have been contaminated by this spill. Maybe the condensate evaporates and dissolves enough that damage inflicted on seabirds is limited. Or maybe we failed to notice the birds that died because of the spill. After all, research from Korea suggests that shearwaters are already threatened by micro-spills and the “chronic oil pollution” that results from the inefficient extraction, transportation, and consumption of oil. It took just that one bird to draw my attention to an already existing problem. Sugawa reported it to an ornithological oil monitoring group.

Anthropologist Frédéric Keck saw the amateur birdwatchers of Taiwan and Hong Kong as “sentinels of environmental change.” Professional ornithologists, with long-term monitoring projects that sometimes span decades, are even more so. Attention to the impact of petroleum on birds suggests that we need to think of various international agreements comprehensively and in relationship to one another. How, for example, does the shipment of oil from Canada threaten the goals of the Convention on Biological Diversity, the Migratory Bird Treaty Act, or the Ramsar Convention on Wetlands? What impact do our political and economic decisions have on non-human lives? These are critical questions for Canada as we debate oil sands development, pipelines, and shipping routes through coastal British Columbia to Asia.

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