Sunday, May 2, 2010

Oil spills: dead birds, bleeding seals...a Kauai example

A dozen years ago, an oil spill off O'ahu from Tesoro's single-point mooring off Barber's Point on O'ahu headed across the Kaieiewaho Channel to Kauai.

Within two weeks, gobs of tar started fouling the shorelines, oiled dead birds began washing up on Kauai beaches and monk seals displayed disturbing signs of respiratory distress, gagging and one appeared to be bleeding from the mouth.

To understand the immense damage posed by the current BP spill in the Gulf of Mexico, consider the impact of a comparatively small spill of thick bunker oil from the August 24, 1998, Tesoro spill.

At the recent projected spill rate of 210,000 gallons a day at the BP well site, the 1998 spill was tiny. At 4,900 gallons, it was the amount of oil released in just a half-hour of the BP spill.

A lot of the focus of the BP spill is on the coastline, and the impacts of oil in the coastal marshes and beaches, but the oil is killing animals offshore as well. The International Bird Rescue Research Center reported treating 33 birds from the spill, of which 14 died before release. It's not known how the released birds did. It's also not known how many other birds were impacted but never recovered.

One estimate is that less than one in four oiled birds ever gets found: “General recovery rates for oiled birds on shorelines range between 20 to 25% or less... the breeding and foraging behaviors of tropical seabirds increases the possibility that these birds could encounter oil and that oiled birds may not be observed or recovered,” says the final restoration plan from that spill.

On Kauai's shore, the oil impacted the reefs and nearshore marine life, from opihi and crabs to the gobies in tide pools. The impacts are outlined in the Final Restoration Plan and Environmental Assessment for the Tesoro spill.

Teams collected samples of the edible limpet, opihi, and found there were detectable oil compounds in their tissues: “Samples gathered … at the oiled boulder areas of Kipu Kai had total polycyclic aromatic hydrocarbon (PAH) concentrations ranging from 140 to 410 parts per million (ppm). This range of concentrations was higher than background levels. Several tissue samples had no detectable PAH's. A second round of representative sampling from the same location at a later point in time suggested that the impacts were not persistent,” the plan said.

The teams noted an oiled turtle as well as oiled monk seals, and some of the oiled seals appeared to be suffering trauma from the oil.

Trustees observed three Hawaiian monk seals during the first survey. The first monk seal (KK01) appeared relatively normal. The second (KK02), which may have been oiled, had its entire oral mucosa coated with a red, blood-like fluid. This animal also acted agitated. The third monk seal (KW01) appeared less than 10% oiled and acted normally.

The Trustees observed the first (KK01) and third (KW01) monk seals again during the second survey. The first (KK01) again appeared normal. The other (KW01) appeared normal initially, but later during the survey showed signs and behavior consistent with an upper respiratory tract infection. Such infection could be an effect of the oil, but neither the infection nor the presence of oil could be confirmed. Although the Trustees did not resight the other monk seal (KK02) from the first survey, they did observe two additional monk seals during this second survey. One (KK03) appeared possibly 1-5% oiled and relatively normal although it did exhibit some "gagging" behavior. The other monk seal (KW02) appeared possibly oiled, but seemed unaffected.”

The 1998 Tesoro spill was a small one, and presumably only a portion of it washed up onto Kauai shores, but its impacts were significant. It is difficult to imagine all the effects of the BP Gulf of Mexico spill on the marine and coastal environment.

Terrestrial reporters often display a sad misunderstanding of the marine impacts of an oil spill. The New York Times refers to the “imminent environmental disaster,” as if it's only going to be a problem if it hits the shore.

The Gulf fishing industry, including the famous shrimp and oyster fisheries, are already suffering. The Associated Press quoted one fisherman, Jimmy Rowell, 61, of Pass Christian, Mississippi.

"'It's over for us. If this oil comes ashore, it's just over for us,' Rowell said angrily, rubbing his forehead. 'Nobody wants no oily shrimp.'"

© Jan TenBruggencate 2010

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