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Brown Pelican (Pelecanus occidentalis)

Written by ABNC Volunteer David Ozro Woods. David is a PhD student of Ecology & Evolution at the University of Houston. He has a bachelor's degree in Natural Resources: Conservation Biology with minors in Marine Science and Plant Science.

The Brown Pelican is a somewhat comical but still elegant large bird that preys on small fish including menhaden, smelt, and anchovies. They hunt by plunge-feeding from far above the water so as to stun their prey before they scoop them up into their throat poaches. Smaller birds have been spotted stealing fish right out of their mouths! They have a long lifespan, typically of around 30 years with the oldest known individual living to be 43.

A P. occidentalis juvenile filling its throat poach with water hoping to catch lunch. (Photo credit: Gary Seloff)

P. occidentalis used to be on the endangered species list since 1970; however, the bird was removed from the list in 2009 following a remarkable recovery in the preceding decades. There are now an estimated 650,000 individuals of P. occidentalis worldwide according to the United States Department of the Interior, which is the highest count ever recorded for the species. Large-scale conservation efforts have been massively important to the recovery of this species, and are a testament to our ability to restore endangered species.

An adult P. occidentalis basking in the sun. Their plumage becomes much more vibrant as they reach adulthood. (Photo credit: Gary Seloff) 

The major reason for the decline of P. occidentalis during the early twentieth century was due to the pesticide DDT (dichloro-diphenyl-trichloroethane), developed as the first synthetic insecticide in the 1940s. It was commonly used to combat mosquito-borne illnesses and was incredibly successful in doing so. Because of this, it was quickly adopted worldwide. However, DDT did not just affect bothersome insects, it built up in the food chain and affected wildlife at all levels, especially birds. Birds that have DDT built up in their system lay fragile eggs, which break before the chick is ready to hatch and thus undermine the bird’s ability to reproduce. This caused massive population crashes in many predatory bird species, including P. occidentalis. It has also been shown to be a probable carcinogen. DDT use has since been discontinued in the United States, but due to the long-lasting nature of the chemical there are still concerns surrounding it.

A majestic adult P. occidentalis in flight. (Photo credit: Gary Seloff)

Pelicans are a special sighting here at the Armand Bayou Nature Center. We are graced by these iconic birds that have recovered from near extinction in recent memory, and are now common and majestic coastal birds here in Houston. They serve as a perpetual reminder of what can be accomplished in conservation if we all work together towards a common goal.

A juvenile P. occidentalis having just caught a small fish. (Photo credit: Gary Seloff)

Further reading:

https://www.allaboutbirds.org/guide/Brown_Pelican/overview

https://www.audubon.org/field-guide/bird/brown-pelican

https://www.americanoceans.org/facts/are-brown-pelicans-endangered/

https://www.epa.gov/ingredients-used-pesticide-products/ddt-brief-history-and-status