Teenage murrelet discovery a highlight of season

  • Sep. 2, 2005 5:00 a.m.

By Heather Ramsay–Finding a 17 year-old ancient murrelet was one of the highlight of another successful field season on Limestone Island says Laskeek Bay executive director Greg Martin.
Along with the 462 ancient murrelet chicks banded during May and part of June, the black oystercatcher survey, sea surveys and more, staff recaptured an adult murrelet first banded in 1990.
Mr. Martin says scientists don’t have a good idea of how long ancient murrelets live, so finding this bird was significant.
The bird was an active breeder when caught, and since ancient murrelets must be at least two years old to breed, the bird is at least 17 years old.
“And it is still breeding,” says Mr. Martin.
The ancient murrelet chick count was up slightly from last year, but still lower than previous years, says Mr. Martin. June 6 was the last night of banding and the first night that no chicks tumbled through the forest toward the sea.
Another highlight was finding five of the 10 nest boxes built for pigeon guillemonts occupied. These boxes were designed in 2001by Tony Gaston, the seabird biologist who helped found the organization. The birds nest in the upper reaches of the tidal zone on rocky ledges, so it is often difficult to observe them in their natural nest cavities.
“This is the highest occupancy rate and the first time we’ve seen chicks in them,” said Mr. Martin.
Although there was a successful seabird breeding season on the islands, Mr. Martin is concerned about ocean trends to the south.
“There are sad things going on in the oceans to the south of us,” he says.
Scientists on Triangle Island, an important seabird colony off the north tip of Vancouver Island, witnessed the worst breeding year on record.
Out of 500,000 pairs of Cassin’s auklets, half the world’s population, not one chick has survived.
Mr. Martin says the problem seems to be due to the lack of oceanic plankton. An upwelling of cold ocean current causes plankton blooms, but the phenomena didn’t occur this year for reasons still unclear. Some think it may be due to global warming.
On Limestone there were 51 active Cassin’s Auklet burrows, locally a jump up from last year, but only a microcosm of the world population.
“We haven’t had the collapse in the food web from warm waters here. But is this a trend? Is it going to happen to us,” asks Mr. Martin.
He says Laskeek Bay scientists are going to continue to keep a close watch on ocean conditions and seabird populations on the islands and will be comparing data with that from the south.