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West Side Highway, LA, United States

Elsey R.M.,5476 Grand Chenier Highway | Lang J.W.,University of Minnesota
Southeastern Naturalist | Year: 2014

The sex of American Alligator (Alligator mississippiensis) hatchlings is determined by the egg temperature during the middle third of the 9-12 week incubation period. As a consequence, predictable sex ratios are possible for clutches incubated in constant temperatures in the laboratory, but naturally occurring sex ratios of American Alligator hatchlings from wild nests exposed to fluctuating temperatures are not well documented. Over a 5-year period (1995-1999), we determined the sex of American Alligator hatchlings from wild nests left in the field until after sex was irreversibly determined. A total of 6226 hatchlings from 232 naturally incubated wild nests showed a strong female bias (71.9% females, yearly range = 62.3-89.4% females). Most nests (64.2%) produced hatchlings of both sexes. Of the remaining clutches that produced exclusively one sex (83 nests), 78 nests produced all females, and 5 nests produced only male hatchlings. For the 2 years in which nest-cavity temperatures were known, higher temperatures led to production of significantly more male hatchlings (P < 0.001 for both 1997 and 1999). Knowledge of natural sex ratios of hatchlings can aid in the management and harvest of this commercially valuable species, and in understanding sex-ratio bias in American Alligator populations. Source


Elsey R.M.,5476 Grand Chenier Highway | Platt S.G.,Wildlife Conservation Society | Shirley M.,Louisiana State University
Southeastern Naturalist | Year: 2015

In Louisiana, Castor canadensis (North American Beaver) rarely occur in coastal marshes and are far more common in forested wetlands. We recently observed a North American Beaver lodge in a coastal marsh that was constructed partly of commercial lumber, possibly made available by recent hurricanes. The animals may have used lumber for lodge construction due to the dearth of trees or other woody vegetation in coastal marshes. This observation points to the adaptability of North American Beaver when choosing materials for lodge construction. Source


Elsey R.M.,5476 Grand Chenier Highway | Mouton E.C.,415 Darnall Road | Kinler N.,415 Darnall Road
Southeastern Naturalist | Year: 2012

Rapid spread of the introduced Sus scrofa (Feral Hog) is a major concern for many landowners and land managers due to its destructive rooting behavior which damages natural habitats. Feral Swine have also been reported as infrequent predators of Alligator mississippiensis (American Alligator) eggs, with only seven nests lost in three prior studies combined (Fogarty 1974, Ruckel and Steele 1984, Woodward et al. 1992). In response to increasing reports by Louisiana landowners of Alligator nest losses due to Feral Swine, we sent a questionnaire addressing this issue to licensed Louisiana Alligator farmers who are permitted to collect eggs from wild nests. Over half (51.4%) of the farmers reported loss of Alligator nests in 2011; some 590 nests were damaged or destroyed on 36 separate properties across the state. Four farmers, some of whom have twenty or more years of experience collecting Alligator eggs, reported this is the first year in which they have lost nests to Feral Swine. Other farmers reported seeing wild hogs while in the field or seeing sign of hogs, which suggests future potential losses may be incurred and that the range and population level of this non-native species is expanding in important Alligator nesting habitat in Louisiana. Nearly all farmers who had nests destroyed by Feral Swine (94.7%) reported hog damage is increasing on their properties. Some farmers reported that hog removal efforts limited their Feral Swine damage this year relative to past years. In addition to deleterious effects on wetlands habitats caused by Feral Swine, the financial impact of loss of the Alligator egg revenue is significant. Source


Rehorek S.J.,Slippery Rock University | Duffy M.,Slippery Rock University | Duffy M.,Lake Erie College | Zacherl J.R.,Slippery Rock University | And 4 more authors.
Journal of Morphology | Year: 2014

The location and distribution of mucosal sensory structures of the crocodilian oral cavity are poorly understood. Although there are several descriptions of these structures in adults, nothing is known about their development. The purpose of this study was to document location, morphology, and relative abundance of these mucosal sensory structures in both hatchling and subadult alligators. Numerous mucosal sensory structures and pale staining dome-shaped papillae were observed only in the upper palate and tongue. In hatchlings, these papillae, which house either mechanoreceptive or chemosensory (taste buds) structures, were larger and more prevalent on the tongue than the upper palate. In the subadult, however, these papillae housed primarily mechanoreceptive structures and possibly degenerate taste buds. Although the presence of the mechanoreceptive structures in the palates of the suabadult alligator are to be expected, the loss of most taste buds is hitherto undocumented. Thus, there is morphological support for an ontogenetic shift in the role of the sensory palate, from a prey detection gustatory sensory system in hatchlings to a prey-manipulative mechanoreceptive system in subadults. © 2014 Wiley Periodicals, Inc. Source

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