Sick pelicans are turning up across Santa Cruz County. Here’s what might be happening.

Phoenix Rumbaugh has volunteered with Native Animal Rescue of Santa Cruz County in Live Oak for about three years now, but he’s never seen the number of injured and sick pelicans he has in the past couple of weeks. 

Just last week, he said, NAR started getting more calls about pelicans, and Rumbaugh took on some more volunteer hours to help address the mystery. Rescuers caught over 40 affected pelicans in just three days. The pelicans have been found starving, malnourished and disoriented around Santa Cruz and its beaches, particularly Cowell Beach. Rescuers have responded to so many calls over the past two weeks that NAR’s shelter is beginning to fill to capacity.

“We’ve been getting significantly more calls in general, but once we go down there, there’s a much larger population,” said Rumbaugh. “[On Sunday,] I got a call about one bird, and when I went down to the beach there were 10.”

NAR wildlife technician Amy Red Feather said that normally, the organization would see two or three sick birds a week. Since April 8, the organization has received 115 pelicans, and is currently caring for 30 of them in its Santa Cruz County facility. She added that International Bird Rescue (IBR) in Fairfield and the Monterey County Society for the Prevention of Cruelty to Animals (SPCA) have taken some of the sick pelicans to lighten the burden on NAR: “It’s been a huge amount more than what we normally see.” 

Rumbaugh’s first — and biggest — concern was the possibility of avian flu taking its toll on the local bird population. Since January 2022, a subtype of highly pathogenic avian influenza has caused the largest outbreak of the disease in recorded history, and has spread to all corners of the globe. Thankfully, said Rumbaugh, IBR has tested the pelicans it has for bird flu and all those tests have come back negative. He added that IBR is taking as many of the birds as it can, but it has limited space as well: “This is an unprecedented amount of birds.”

So if it isn’t avian flu, then what could be causing the widespread ailments? 

The folks at NAR have a couple ideas. Red Feather says it appears that starvation is the main driver of the birds’ disoriented, unusual behavior and illness. She said that NAR staff are giving the birds a lot of fish every day, and they’re eating it immediately. The birds still have to double their current weight in order to be deemed fit for release.

Red Feather said this apparent difficulty in finding food might be a purely natural coincidence. She said that sometimes local fish numbers dwindle simply because the fish have traveled out of the area. There are far more fish in San Francisco Bay right now than in Monterey Bay, Red Feather said. The lack of easily accessible food could be causing the birds’ tendency to eat items they shouldn’t be eating as well as their general confusion.

“From what I heard, International Bird Rescue is going to be releasing these pelicans somewhere where there’s more fish,” she said. “So it could be completely natural.”

The second, and more dramatic, hypothesis is that the birds are dealing with domoic acid poisoning. That can happen when algae accumulates in shellfish and smaller fish, which then poisons the predators that hunt the animals. This phenomenon is now often cited as the cause of a large seabird attack in Capitola in 1961 — which ended up serving as the inspiration for some of the events depicted in Alfred Hitchcock’s iconic avian-themed thriller “The Birds.”

“Seabirds like to eat small bait fish like anchovies and sardines, and those have a tendency to build up all of those toxins and become toxic to the birds,” said Rumbaugh. “When they get poisoned by this, they lose their sense of direction.”

“That could happen at any time,” said Red Feather, adding that there have been reports of pelicans stumbling into restaurants and bars, which could back up the domoic acid poisoning theory. “If we see more of them starting to act really bizarre, that could be a stronger hypothesis that we may be dealing with domoic acid.”

But as of now, there are no clear answers. Red Feather said IBR scientists are working to figure out the cause, and she is confident they will find an answer. However, there might not be a definitive conclusion for some time.

“We don’t usually find out until after the incident is over,” she said. “We’re usually the last to find out what causes the problems in the food chain and with the animals.”

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