Gulf coast ecology

The Gulf of Mexico remains a region in peril as the long-term effects of erosion, rising sea levels, anthropogenic disturbance such as oil spills and natural disasters like hurricanes combine to gradually deteriorate the ecosystem over time. While recent management efforts have aided in slowing some declines, such as the loss of several barrier island chains, more integrative work is necessary in order to understand the processes that affect the rich ecological community supported by the Gulf. This approach will help to preserve a piece of the natural world that is commercially, recreationally, and biologically vital.

 
 

Our current research in the area is focused on the foraging ecology of the brown pelican (Pelecanus occidentalis), an iconic symbol of the Gulf and a top predator about which there is still much to be learned. In 2012, we began monitoring the movements of breeding individuals nesting on colonies throughout the region and considering various endogenous and exogenous factors that may influence their foraging behavior. This initial work suggested that variability in prey abundance across the region could be key to understanding brown pelican movement ecology and nest success at the regional scale. Brown pelicans feed almost entirely on gulf menhaden (Brevoortia patronus), a schooling fish species that is also economically important to human fisheries. Menhaden schools are known to respond to changes in the environment, including large disturbances such as the emergence of marine hypoxic zones. In collaboration with NOAA and Dr. Paul Leberg from the University of Louisiana at Lafayette, post-doctoral fellow Dr. Scott Walter and PhD student Brock Geary are using GPS tags on pelicans and analysis of fisheries data to study the relationships between menhaden distribution and abundance, environmental variability, fisheries productivity, and pelican nesting success

 

While holding important implications in brown pelican biology, our research will also make contributions to a larger body of ecological theory concerning the evolution of predator foraging strategies in environments that are patchy and unstable at a variety of scales. Our modeling of annual variability in prey availability and pelican nesting success also has the potential to incorporate other members of the Gulf coast community in the future, enabling us to more comprehensively explain and project changes in the ecology of the region. This will allow for our involvement in informed recommendations for coastal restoration, fisheries regulation, and local education and environmental awareness.

 

 

Related Publications


2014

Walter, S. T., M. R. Carloss, T. J. Hess, and P. Leberg. 2014. Demographic trends of Brown Pelicans in Louisiana before and after the Deepwater Horizon oil spill. Journal of Field Ornithology 85:4 421-429. PDF

2014

Walter, S.T., P. L. Leberg, J. J. Dindo, and J. Karubian. 2014. Factors influencing Brown Pelican (Pelecanus occidentalis) foraging movement patterns during the breeding season. Canadian Journal of Zoology 92:885-891. PDF

2013

Walter, S.T., M.R. Carloss, T.J. Hess, G. Athrey, and P.L. Leberg. 2013. Brown Pelican movement patterns and population structure. Condor 115:788-799. PDF

2013

Walter, S.T., M.R. Carloss, T.J. Hess, and P.L. Leberg. 2013. Hurricane, habitat degradation, and land loss effects on Brown Pelican nesting colonies. Journal of Coastal Research 29:187-195. PDF

2013

Walter, S.T., M.R. Carloss, T.J. Hess, G. Athrey, and P.L. Leberg. 2013. Brown Pelican (Pelecanus occidentalis) colony initiation attempts: Translocations and decoys. Waterbirds 36:53-62. PDF