How Pelicans Have Thrived Despite Adversities
During a recent survey conducted in Santa Barbara, California, researchers found that the California brown pelican has a 70 percent survival rate. The findings are being used to aid conservation efforts to protect these birds. The study also found that there is a definite increase in the population of these birds as well. These birds have suffered from a variety of threats such as loss of habitat, loss of sardines, and marine toxins.
California brown pelican
Hundreds of brown pelicans have been rescued and cared for by the Santa Barbara Wildlife Care Network in the past month. The organization estimates that the survival rate of the rescued birds is 70 percent.
The California brown pelican (SCB) is a seabird that breeds on two islands in the Channel Islands: Santa Barbara Island and West Anacapa Island. The pelicans are protected in California as a marine species.
The SCB was listed as federally endangered in 1970 due to the impacts of pesticide DDT. The brown pelican made a remarkable recovery after DDT was banned. The species is now fully protected in California. The California Department of Fish and Wildlife (CDFW) is working with the U.S. Fish and Wildlife Service (USFS) to help the brown pelican recover.
The first two recovery criteria are met: habitat is protected and self-sustaining populations are established in Mexico. However, the third criterion, productivity, has yet to be met.
The goal of the brown pelican recovery plan is to return the SCB to self-sustaining population levels in the colonies. The plan also calls for long-term protection of food sources and essential habitat. It also calls for the establishment of additional nesting colonies in Mexico.
Nesting failures
Despite nesting failures, the California brown pelican has a 70 percent survival rate in Santa Barbara – a tiny island in the Southern California Sea. The island supports one of the largest nesting colonies in the West Coast.
California brown pelicans breed in two Channel Islands: Anacapa and Santa Barbara. They also nest in Baja California, Mexico. Despite the fact that their population has recovered to the extent of their East Coast cousins, they are still federally endangered.
They were once thought to be extinct. Their numbers were nearly wiped out by a pesticide called DDT. DDT changed eggshells and altered the pelicans’ ability to metabolize calcium. The pesticide was banned in 1972. Since then, the California brown pelican population has grown by about 712 percent.
Today, the population is thriving on windswept plateaus and rugged cliffs. The number of nesting pairs has been steadily increasing since 1985. Today, the California brown pelican population reaches 4,000 to 6,000 pairs.
The nesting success of California brown pelicans is closely tied to the number of food sources around the nesting sites. Anchovies are an important food source, but they are waning in numbers. In fact, anchovies are not replacing the sardines that have been the source of food for pelicans for hundreds of years.
Sea lions
Despite the presence of leptospirosis, which can lead to kidney failure or worse. The California sea lion population has stabilized. According to the U.S. Marine Mammal Protection Act of 1972, the population is sustainable when it has reached the maximum net productivity level.
Researchers are studying the long-term effects of this outbreak. According to Shawn Johnson, director of veterinary science at the Marine Mammal Center in San Francisco, “The number of cases is going to slow down. This is probably due to the fact that the sea lions are starting to get used to warmer waters. It also is due to the fact that they are moving north and they are starting to find new breeding grounds.”
During the first year, the pups are often sick. After they are rehabilitated, they can return to the sea. A typical rehab period takes 6 to 8 weeks.
Wetland and marine toxins
Hundreds of brown pelicans are flocking to the coasts of Southern California. This is the first inland breeding occurrence of these birds. They are commonly found on the southern coasts of the US. Their ranges also extend south to South America. They are listed as endangered by the U.S. Fish and Wildlife Service in 1972.
Brown pelicans are one of only two species of pelicans that dive into the ocean to catch food. They are known for eating Herring and smelt. They range in size from eight to ten pounds. The wingspan is six to seven feet. They are usually found in large flocks.
In the summer of 1996, more than a thousand California brown pelicans perished due to severe circumstances.
Scientists have been investigating algal toxins in the Salton Sea.
Loss of sardines
Whether it’s the first of June or the last of December, California brown pelicans haven’t been flying. In fact, they’ve been falling by the wayside since mid-May. The culprit: a disappearing Pacific sardine population, which has repercussions for the entire ecosystem.
As you can imagine, there hasn’t been a lot of sardine fishing activity. This is a bummer for commercial fishermen and the marine ecosystems that rely on this food source. In fact, the sardine population has been estimated at approximately 97,000 metric tons in 2015. The state of California has a historic fishing industry, with the “wetfish” industry making up about 80 percent of the state’s total fishing landings.
The “wetfish” industry consists of hundreds of species of fish and marine life that are fished in and around coastal waters. The sardine industry, in particular, is critical to California’s fishing industry as well as to the state’s economy as a whole.
Despite the plethora of regulations on the books, the sardine industry has largely failed to meet its fish stock and harvest requirements. This has resulted in unprecedented starvation among sea lions and other seabirds. In addition, the absence of sardines has resulted in widespread failure of nesting by Brandt’s cormorants.
Increase in population
During the winter of 2008-2009, a large number of pelicans began washing up on beaches in California. In the Pacific Northwest, 300 to 400 pelicans were reported perished during an event involving a winter storm. This is the first time a large number of pelicans have washed up on California beaches in recent memory.
The brown pelican is an iconic species of coastal habitats. It feeds on a variety of prey items, including mackerel, Pacific sardines, and northern anchovies. Being a long-lived species that can adapt to changing food sources. It is also a generalist in prey sources, which may result in populations that vary in size and distribution.
It was not until 2009 that it was removed from the endangered species list. This was touted as a successful recovery for the species.
Although there have been many documented adverse effects on nesting pelicans, it is not clear why these events occurred. They have been shown to adversely affect the success of pelicans, causing the abandonment of nests, and possibly starvation of nestlings.
Joe Jehl’s interest in pelicans
Throughout the past decade, California brown pelicans have been making a big push to nest on West Anacapa Island. However, productivity has remained below average for years. The breeding season on the island begins early May and continues through mid-August. In 1992, the breeding season was shorter.
In the 1990s, the US Fish and Wildlife Service removed the California brown pelican from its list of endangered and threatened species. The Migratory Bird Treaty Act, however, continues to protect the species. The California brown pelican is protected at several locations along both coasts of Baja.
The California brown pelican is a seabird, which lays three eggs. Its wingspan is over 6.5 feet. It has a brown body and a pale yellow head with an occipital crest. Weighing a whopping eight pounds. It has short dark legs and webbing between its four toes.
Its breeding range extends from the Channel Islands to central Mexico.
Provided by Antonio Westley
Disclaimer: This article is meant to be seen as an overview of this subject and not a reflection of viewpoints or opinions as nothing is definitive. So, make sure to do your research and feel free to use this information at your own discretion.
