Brown Pelicans Failing to Breed

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Brown Pelican

Malibu seems to have more V-shaped pelican squadrons flying along the coast than ever before, and there’s a reason.  

Most haven’t bothered to make the annual trip to the Channel Islands or Baja Mexico to breed and raise their young. In fact, experts say many haven’t bothered going for the last four or five years.

The 2014 pelican breeding season is proving to be the worst yet, reaching the lowest levels recorded since the pesticide DDT, which prevented eggs from hatching, was banned in 1972. The birds had been placed on the endangered species list for over 30 years, until 2009. Now, their future is uncertain once again.

The few pelicans that tried traveling to the breeding grounds often came back early after their nesting attempts failed due to lack of food. 

“It’s about five months from courtship until the young leave the nest,” said Dan Anderson, professor emeritus of wildlife biology at UC Davis. “They need from 100 to 150 pounds of fish for each of the young they raise.”

As scientists try to pinpoint a reason, most signs point to a severe decline in the sardine population — a staple in the brown pelican diet.

Oil-rich sardines have declined precipitously along the West Coast since 2007, and the pelican population has declined along with it.

The National Oceanic and Atmospheric Administration (NOAA) has come under fire for poor fish management practices that allowed overfishing of sardines since 2007, causing the starvation and malnourishment of not just pelicans, but many other seabirds and marine mammals.

Desperately hungry pelicans are showing up in all sorts of unusual places and not following their usual yearly breeding timetables.

Dan Cooper, a biologist who has monitored birds at Malibu Lagoon for various agencies since 2005, said he first noticed the birds’ altered schedule in mid-April. 

“I was just sort of flabbergasted at seeing 3,500 brown pelicans resting in Malibu Lagoon,” Cooper said. “I checked my notes, and I’ve seen hundreds, but never anything like that.” 

At that time of year, most adults should have been nesting and raising young on offshore islands. The lagoon flock has since dispersed.

In an email, Cooper said he had received reports of 10,000 brown pelicans on East Sand Island, Ore., as well as reports of hundreds showing up on Monterey Bay—places they would not normally be this time of year.

In fact, biologists were shocked when pelicans were first observed attempting to start a breeding colony in Oregon. 

“To me, it was earth-shaking,” biologist Deborah Jaques told the Statesman Journal last month. “It’s never been recorded in modern history to have pelicans nesting this far north. The farthest north they’ve been known to nest before was Monterey in the ‘50s. Other than that, it’s always been confined to Southern California.”

“It’s possible pelicans are lacking the food they need farther south and are finding it farther north…And they’re not just coming up north earlier, they’re also staying later in the year,” Jaques said.

Biologist Dan Roby, in an Oregon Public Broadcasting article, thinks the change could also “be linked to global climate change, because quite a few birds are shifting their range farther and farther north as the climate warms.”

In U.C. Davis News & Information last month, Anderson said that in his just-completed 46th annual pelican breeding survey from Baja Mexico, where 80-90 percent of pelicans hatch, California’s brown pelican breeding numbers have collapsed, and are estimated to be 99 percent lower than normal.

“It’s been an almost complete failure to breed, which is quite unusual,” Anderson said. “One island we study would normally have 8,000-10,000 young, and only had 20 young…That’s what we call a bust—the bottom dropped out.”

Biologist Laurie Harvey found similar results on the Channel Islands. Independently monitoring pelicans in 2012, she told Yale Environment 360 that she found only five chicks on Anacapa Island, whereas six years earlier, there were 10,000. In 2013, Kate Faulkner of NPS said production was “very poor.”

Low breeding numbers could also be associated with El Niño’s ocean warming effects, but pelicans are showing signs of trouble well ahead of the El Niño.

“Populations do decline somewhat during El Niño years, but not as drastically as what we saw widespread this year,” Anderson said. “During most El Niño events we’ve seen, numbers of nesting attempts drop by at least half to two-thirds, but it drops from thousands to hundreds, not to 10 or less.”