Death event of seabirds points to larger global change, biologist says

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Josh Pennell
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A biologist who collected more than 200 dead and dying seabirds on Holyrood Beach in January has begun dissecting the specimens and the findings, though preliminary, suggest more devastating forces at work than the storm that blew the birds in.
A savage winter storm Jan. 12 and 13 created a "remarkable and unusual event," according to biologist and MUN professor Ian Jones.

That event is known as a "wreck" - an incident whereby birds in a weakened condition are blown toward land by heavy winds. In this case, the birds that formed the wreck were dovekies, or bull birds. Jones collected 228 dead and dying dovekies on Holyrood Beach that weekend.

"When picking up these birds it was immediately apparent that they were very emaciated. Very skinny. Very light in weight," Jones says.

Seeing so many freshly dead birds was a horrific sight, but also an exciting one from a scientific point of view.

Jones explains that the body temperature of a seabird is close to 40 C. When they die, residual heat in the body causes decomposition to occur very quickly. Jones placed each of the dead birds in a separate bag and took them to the university freezers, where they became a kind of frozen physiological moment in time.

"They provide a really remarkable window to provide scientists with a way of evaluating the cause of their death," says Jones.

Such information couldn't be deduced if the birds hadn't been frozen so quickly after death.

It was only recently Jones was able to look at the frozen dovekies. He had his fourth-year ornithology class help in conducting necropsies on 22 of the 228 birds - a small portion of the total, but the findings were still interesting. A healthy seabird will have a thick layer of subcutaneous fat, Jones says.

"As soon as we opened these birds, we looked for signs of subcutaneous fat and none of these birds had any fat on them at all, which is completely characteristic and diagnostic of starvation."

The gizzard of a bird is a muscular organ that grinds up food, and it's in this that Jones and his class expected to find the birds' last meal.

"There weren't any food items in their gizzards at all," he says.

There were a few unwelcome items, however. One of the first birds they opened had a two-centimetre by one-centimetre fragment of an Aquafina bottled water label and another similar piece of plastic in its gizzard.

"So basically the last thing this bird ate before it died were these two pieces of drifting plastic," says Jones.

About half of the birds they opened had foreign objects in their gizzards. Some had plastic and others had other man-made debris that will have to be identified with a microscope.

Plastic is extremely detrimental to a bird's health, as well as to other marine life such as fish, turtles, sharks and mammals. If a healthy bird eats plastic, it blocks the digestive tract, says Jones.

There are more and more reports of the amount of plastic floating around the oceans and this is one more anecodote of that, but suggesting these birds ate plastic and died from it is not the correlation, he says.

"That's an oversimplification of what's going on."

The dovekies breed in Arctic Norway and Greenland and move into Newfoundland waters to overwinter. The waters here are ordinarily cold and extremely productive. Jones says last January and the autumn previous, water temperatures around the island were a couple degrees higher than usual and that negatively affects ocean productivity.

"They just basically landed in a big patch of ocean with no food in it and they came ashore and starved," says Jones.

The problem is bigger than the event, he warns. Like the food chain, everything here is connected, he said, but the sequence the pieces form doesn't have the natural beauty of a food chain. The plastic in the ocean is an example of the pollution people cause. In many scientists' opinion, it's pollution that's causing global warming, and that global warming is causing changes to ecosystems such as a warming ocean temperature.

"(That's the) one caveat about this," says Jones.

Dovekies are fine after this one event, he says. But it's another anecodote in the story that points to larger change.

Organizations: Aquafina

Geographic location: Arctic Norway, Greenland, Newfoundland

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