That Dead Bird on Your Beach Holds Clues to Ocean Health



Lohrmann (left) and Garrison survey Sunset State Beach in Watsonville.


Birds have often been heavily scavenged, but most can still be identified.


BeachCOMBERS volunteers Donna Lohrmann (left) and Judy Garrison.


Garrison clips a toe from each bird to show it has been counted this month.


Seabird stomach contents are weighed and sorted into petri dishes.

Story & photos by Kelly Servick | KUSP News
For the average beachgoer, dead animals on the shore are a gruesome distraction from the beauty of the sand and surf. But for a team of volunteers and scientists on the Central Coast, they’re valuable forensic clues. An ongoing project seeks to document these animals and reveal the startling amount of plastic in their stomachs.

Judy Garrison and Donna Lohrmann are out for a morning walk on Manresa State Beach near Watsonville. Their pace quickens when they spot a heap of feathers ahead. With rubber gloves, Garrison picks up the bird carcass and turns it over. It has begun to decompose and has lost some of its innards. It has a nauseating smell.

Garrison and Lohrmann will document every dead bird and mammal they find on this three-and-a-half-mile stretch of coast. As volunteers with a project called BeachCOMBERS, they help scientists monitor the ocean by counting the unlucky creatures that have died and washed ashore. BeachCOMBERS volunteers are trained to identify local species, even when they’re decayed or scavenged. To make sure nothing gets double-counted next month, they clip a toe from each bird with wire cutters.

Secret Lives of Seabirds

Teams of BeachCOMBERS have been scouring the Central Coast for the last fifteen years. Every month, 74 volunteers survey nearly 30 miles of beach. The bodies on the shore offer a glimpse into a world that scientists can’t access any other way.

“A lot of these birds only come to islands to nest, and the rest of the year, they’re out on the open sea,” says seabird biologist Hannah Nevins of the Department of Fish and Wildlife, who manages the project. “Where they go, what they eat and when they mature – all that kind of information isn’t known for a lot of these species.”

Once scientists know how much death is normal, they can identify a spike that suggests something’s wrong. In the past, BeachCOMBERS have traced deaths back to:

  • toxic algal blooms, which sometimes create a “mystery goop” in seabird feathers and compromise their waterproof qualities
  • oil spills, like discharge from the 1953 wreck of the S.S. Luckenback in San Francisco Bay (BeachCOMBERS data led to a 22.7 million-dollar cleanup effort.)
  • harmful fisheries, whose use of gill netting can trap and kill birds or mammals diving in the area

Troubling Finds

When volunteers come upon freshly dead seabirds, they send them to the Marine Wildlife Veterinary Care and Research Center at Long Marine Labs for a necropsy – the animal version of an autopsy. Marine biologist Erica Donnelly-Greenen performs the necropsies, sorts through the birds’ stomach contents and categorizes them in Petri dishes.

“It gives us a glimpse of what the birds are coming across out there: not just their prey items, but also all the debris that humans are creating that ends up in our ocean and our waterways,” she says.

Birds in the family Procellariidae, like fulmars and petrels, forage for food over large areas of open ocean, and as Donnelly-Greenen has discovered, some things they scoop up aren’t fit to eat. She says birds collected from California beaches contain surprising amounts of debris, including pieces of plastic, fishing line and balloons. Of the northern fulmars in the lab, 98 percent had plastic in their stomachs.

“We’ve also found an entire glow stick in one of the albatross stomachs,” she says. “So that’s a little bit alarming, because that’s a pretty large fragment.”

Not all human impacts are as obvious as a glow stick inside an albatross, but changes in the abundance or range of the species on the beach can reflect more subtle changes in climate. While the scientists explore the data, volunteers will keep feeding the database, one bird at a time.

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