Plastic-stuffed seabirds raise alarm for Australian ocean health

Plastic-stuffed seabirds raise alarm for Australian ocean health

What they found is shocking: of the 100 dead birds dissected this year, only four had not swallowed plastic. A bird had ingested more than 200 pieces of plastic, which is still not a record. Another ate “only” 125 pieces, but they were large, sharp fragments that weighed 35 grams, or about 8% of the bird’s body mass. Rarely is the plastic intact enough to bear a tag, but when it does it often reveals an Australian mark.

Dr Lavers holds a live shearwater on Lord Howe Island last week.

Dr Lavers holds a live shearwater on Lord Howe Island last week.

Adult shearwaters fly over the Tasman Sea between Sydney and Brisbane and skim plastic from the surface of the ocean to bring the chicks back to their burrows on Lord Howe Island. “They regurgitation feed the chicks, thinking they’re bringing them squid, but they lovingly feed their chicks to death,” Lavers says.

Plastic is removed from a dead shearwater on Lord Howe Island.

Plastic is removed from a dead shearwater on Lord Howe Island. Credit:Jenn Lavers/Adrift Lab

The 15-year study dataset shows year-to-year variability, but on average the amount of plastic ingested has increased and the health and condition of the birds has decreased. The young birds are smaller, have less body fat and in poorer condition, which puts the odds in their favor in their long migration.

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This year, plastic levels were exceptionally high, but it’s unclear why. Oceanographic conditions could be driving the change, or perhaps the prey are scared and the birds are desperate and ready to consume things they normally wouldn’t eat.

Overall, scientists still don’t understand why some species of birds eat large amounts of plastic and others don’t.

Seabirds have an incredible sense of smell that guides them to fish, and the current theory is that over time plastics develop an algae-rich “biofilm” on the surface that emits the same chemical released by plastics. schools of fish.

This plastic has been in the ocean for so long that it no longer looks or smells like plastic, and wildlife assumes it is edible.

Lavers’ work takes a heavy emotional toll on her and her younger colleagues. Plastics are everything she reads, talks about, studies and thinks about, she says: “I feel like I live, eat and breathe plastics.” And that makes it hard to have hope. When single-use plastics or balloons outside are banned, as they were in Victoria last year, people expect her to be thrilled.

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But that’s not enough, she says. “We need the rate of positive change to match the rate of negative change in birds. As a human society, we have always relied on seabirds as sentinels. This 15-year dataset tells us what we need to know: plastic is on the rise and its health is on the decline. When are we going to listen?

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