The majestic pelican should have been spreading his wings, flying, feeding. But he wasn’t even eating today, or yesterday. What was wrong with him? It was a mystery to everyone — except the pelican. And he wasn’t talking…
Although it’s a familiar sight on many southern California beaches, seeing groups of brown pelicans, my recent trip to Ventura beach was the first time I’d witnessed this spectacular display for myself. To see these huge birds action was awe-inspiring, and I fell in love with them. Then, I heard about this year’s ‘pelican crisis’.
In May of this year, dozens of injured or starving pelicans began inundating local wildlife rescue centers. The birds seemed confused and hungry, but no signs of any known neurological/respiratory problems, or illnesses were reported. The CDFW was ‘unable to provide information on the underlying cause of this event at this time’. I wanted to know what was happening.
Starvation seemed to be the key factor in this crisis. Pelicans feed mainly on northern anchovy, the Pacific sardine, and sometimes, the Pacific mackerel. There has been a sharp decline in the Pacific Coast populations of sardines in recent years — some say as much as a 95% decline since 2006, largely due to over harvesting. Is this what was causing the pelican crisis?
Pelicans are one of many indicator species that can reveal the health of a marine ecosystem. Clearly, the California marine ecosystem is suffering, but, I looked back at the history of pelicans in crisis.
In the fall of 2009, Brown Pelicans were removed from the Endangered Species list due to their ‘significant recovery’.
But, in February of 2010, there was a similar pelican crisis. The birds found then also appeared ‘hungry and disoriented’, and were discovered to be eating unusual prey instead of sardines and anchovies. Many of the pelicans were reported to have some ‘unidentified residue’ on their feathers, but scientists did not identify the residue. Theories included red tide, pollution runoff, but nothing was reported.
The pelican’s initial species recovery in 2009 was largely due to the banning of DDT. However, in 2011, just two years after the pelican was removed from the endangered list (and one year after that crisis), a previously unknown DDT dump site was found off the California coast. Thousands upon thousands of barrels were shipped out to a secret location and dumped into the ocean. The site, on the ocean floor off the Palos Verdes Peninsula, is now the world’s largest deposit. One federal report stated the ecological consequences will last at least another century, because the DDT is slowly being released to the surface from the ocean floor.
The California brown pelican stays close to the shore to hunt for food — usually within five miles of land, and is one of the only pelicans that is a plunge diver. They usually dive from ten to thirty feet above the surface, but sometimes as much as one hundred feet. They can eat over four pounds of fish each day.
Are declining fish populations solely to blame for the crisis?
And is it overfishing, ecological, or…?
Scientists tested the fish off the Southern California coast and were surprised to discover that since the late 1970s, the levels of DDT contamination “haven’t gone down much at all,” according to Robert Risebrough, UC Berkeley research ecologist. Birds and mammals that feed on fish still suffer the effects, having the highest levels of DDT.
In May 2018, it happened again — a pelican crisis. Scores of birds were coming into bird rehab centers along the California coast. Most were starving and disoriented, some were anemic.
What is causing these repeated crises?
I checked the weather records, and, in all three cases, there was a significant heat spike right around the time of the crisis.
Warmer ocean temperatures can impact fish reproduction, migration patterns, and food availability. During recent marine heat waves, northern anchovy and Pacific sardine populations fluctuated dramatically — anchovy populations skyrocketed, while sardine populations declined. These species serve as baitfish for the commercial fishing industry, but also serve as a large part of the diet of sea birds and sea lions.
Is this the key?
Monitoring of brown pelicans, particularly during these crises, and the preservation of the pelican habitats, is crucial for the continued survival of the California brown pelican population. According to wildlife biologists, ‘pelicans can recover’.
Pelicans still face many threats — perhaps they need to be re-listed as endangered?
I will continue to enjoy seeing these intelligent birds along the shore, and listen for news that solves the pelican mystery.
