Rockefeller Wildlife Refuge
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Current Staff and Collaborative Research

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Alligator
Recent alligator research led by Dr. Ruth Elsey at Rockefeller Wildlife Refuge (RWR) has focused on nesting biology, DNA/genetic studies, and culture studies to refine alligator growth and nutrition. We have recently published studies on commensal nesting nesting species in alligator nests (Elsey et al. 2013), sex ratios in wild American alligators (Elsey and Lang 2014), and microbial symbioses in alligators (Keenan and Elsey 2015).  We have also investigated the impact of invasive feral swine on alligator nests (Elsey et al. 2012) and a three year summary of this problem was presented at a conference in 2014 (Elsey 2015, in press).  The juvenile alligator growth studies are directly applicable for alligator husbandry recommendations made to our state’s alligator farmers.  Recent investigations related to our farm-release to the wild program have documented long-term survival in farm-released alligators (Elsey 2013) and interstate movement of alligators (Elsey and Flynt 2013).  Visiting researchers are often hosted at RWR for collaborative projects of mutual interest. Molecular ecology techniques, such as use of microsatellites and stable isotopes, are beyond the scope of our field site, but working with university professors and graduate students has led to many new findings. Field studies on-site recently documented multi-year, multiple paternity and nest-site fidelity in some alligators, often over several years (Elsey et al. 2008; Lance et al. 2009).  Many researchers from prestigious universities have visited RWR to collect valuable samples for their novel studies. 

For more information about the Alligator Program in Louisiana (including information about tag allocations, permits, and regulations), visit the Louisiana Department of Wildlife and Fisheries website.

Waterfowl

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Studies on Mottled Ducks (Anas fulvigula) at RWR have been ongoing since the mid 1980s, with increasing effort since the 1990s when neighboring Texas observed Mottled Duck population declines. Starting in 1994, Coastal and Non-game Resources Division personnel (including RWR) have banded >40,000 Mottled Ducks.  Annual banding operations occur during the summer to catch flightless juveniles and molting adults, while also permitting research-related projects.  Mottled Ducks exhibit high site fidelity, and subsequently, many are harvested by hunters within 10-15 miles of where they are banded. However, a few stray from coastal Louisiana including one female that was harvested in South Dakota, the farthest north recorded for the species.  The most recent research project is to document hybridization and population genetic structure of the western Gulf Coast population of Mottled Ducks (in collaboration with Robert Ford and Dr. Sabrina Taylor of Louisiana State University).  

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Black-bellied Whistling Ducks (BBWD; Dendrocygna autumnalis) have greatly expanded their range since the mid 1990s to include southern Louisiana and recently as far east as the Carolinas. BBWD banding efforts have been ongoing in Louisiana since 2010 in collaboration with LDWF Waterfowl Biologist Paul Link.  These efforts have included southwestern Louisiana and areas surrounding RWR.  Pilot research by Dr. Bruce Davis (former RWR biologist) used satellite telemetry to investigate home range and movements of male BBWDs.  RWR is contributing towards further understanding this species in southern Louisiana.  However, future research is needed with this species to determine the annual survivorship, home range, and movements of this rapidly range-expanding species.

RWR biologists have been aerially surveying all LDWF coastal refuges and WMAs since the early 2000s.  Waterfowl surveys on established transects or zones are conducted 3-5 times per year before, during, and after the waterfowl hunting season. Waterfowl species are counted for each refuge/WMA, and thus, a long-term dataset has been developed for all coastal areas and for different waterfowl species.  Currently, Dr. Will Selman is working with Larry Reynolds (LDWF Waterfowl Program Leader) and Dr. Kevin Ringelman at Louisiana State University to determine long-term trends of waterfowl species in coastal Louisiana. 

Non-game Birds

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Along with waterfowl, RWR staff are also involved with non-game bird species monitoring and conservation. Recently, RWR biologists completed a year-long bird inventory of Rabbit Island, the most important colonial waterbird nesting island in Calcasieu Lake (Cameron Parish). Rabbit Island harbors the only Brown Pelican (Pelecanus occidentalis) nesting colony in southwestern Louisiana (~2000 nests), with 60+ species also observed on the island.  This includes observing nesting American Oystercatchers (Haematopus palliatus) and Reddish Egrets (Egretta rufescens) on the island, the first such nesting records for either species in southwestern Louisiana.  Both of these birds are poorly understood in coastal Louisiana and future research will investigate the nesting ecology of both species in Louisiana. We also plan to track Reddish Egrets throughout coastal Louisiana to determine important foraging areas, movements, and seasonal habitat use (in collaboration with LDWF Natural Heritage biologists).  

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RWR has annually conducted Piping Plover (Charadrius melodus) winter surveys along beaches in southwestern Louisiana, but little else is known about shorebird communities in southwestern Louisiana.  Dr. Will Selman is collaborating with Abigail Arfman and Dr. Eddie Lyons from McNeese State University to investigate seasonal abundance of shorebirds and benthic prey items at four beaches in Cameron Parish (including Rockefeller Beach).  Each beach is structurally different from the others, with each beach likely harboring a unique community of shorebirds and prey items.

Diamondback Terrapins

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Recent Diamondback Terrapin (Malaclemys terrapin) research led by Dr. Will Selman has focused on terrapin distribution and abundance in southwestern Louisiana, particularly to determine if terrapin populations persist in historical localities and/or if they occur in new locations.  Ultrasound and radiographic studies (i.e., x-rays) are also ongoing to document the specifics of terrapin reproduction, including documenting clutch size (number of eggs) and clutch frequency (number of clutches per nesting season).  Terrapin research has also investigated population structure and demography, with other questions focusing on population genetics of terrapins in Louisiana, temporal and spatial variation in diet, and pattern/color analysis; many of the latter topics are collaborative projects with graduate students.