Evaluation of Attractants to Improve Trapping Success of Nutria on Louisiana Coastal Marsh

ABSTRACT Nutria (Myocastor coypus) are an important part of the Louisiana (USA) fur industry, but high densities of nutria cause extensive damage to coastal marsh ecosystems. Hence, there is a need to develop improved methods for targeted management of nutria. We screened 14 olfactory cues as potential lures for nutria, first in controlled settings and then in the field, to see if nutria capture rates using foothold traps would increase. In Y-maze trials, nutria most frequently selected olfactory cues of a synthetic formulation of nutria anal-gland secretion and nutria fur extract. We examined the 3 most selected attractants in Y-maze trials and female nutria urine under field conditions to compare trapping success over untreated traps. Capture probability was nearly 2.5 times greater for fur wash than control and 2 times greater for urine than control (relative risk = 2.43 and 2.01, respectively). The results suggest that use of semiochemicals and synthetic formulations of semiochemicals increased nutria trapping success. Development and use of effective synthetic semiochemicals could benefit resource managers nationwide who are responsible for reducing damage caused by this invasive herbivore.     

Parental Development of Eimerian Coccidia in Sandhill and Whopping Cranes1

In contrast with isosporoid species of coccidia that have established extraintestinal phases of development, the eimeriids, except for a few species, generally have been considered inhabitants of the intestinal tract. Eimeria infection in sandhill cranes (Grus canadensis) and whooping cranes (G. americana) may result in disseminated visceral coccidiosis. Nodules were observed in the oral cavity of 33% (n = 95) of the G. canadensis at the Patuxent Wildlife Research Center (PWRC) in Laurel, MD. Necropsy of six of the afflicted cranes revealed granulomatous nodules in many tissues and organs. Histologic studies disclosed protozoan organisms morphologically resembling schizonts in the granulomas, and endogenous stages of coccidia were present in the intestines of four birds. Fecalysis of three of four sandhill cranes yielded oocysts of E. reichenowi and E. gruis. Only E. reichenowi-type oocysts were recovered from a dead whooping crane sample. Domestic broiler chicks each intubated with about 1 times 10⁶ pooled sporulated oocysts of E. reichenowi and E. gruis were not infected. Exposure of six incubator-hatched and hand-reared sandhill crane chicks to oocysts artificially (two chicks) and naturally (four chicks) resulted in typical infection of intestinal epithelium with invasion of subepithelial tissues extending to the muscular layer and widespread extraintestinal development. Asexual and sexual stages occurred primarily in macrophages in the liver, spleen, heart, and lung. In the lung, oocysts were found in bronchial exudate and epithelial lining cells. Six of ten G. canadensis chicks, one adult G. americana, and three of five G. americana chicks that died naturally at PWRC had disseminated visceral coccidiosis.     

Long-Term Retention of a Relocated Population of Gopher Tortoises

Abstract: Relocations of gopher tortoises (Gopherus polyphemus) in Florida, USA, are frequently employed as mitigation tools when tortoises occupy land desired for development. Here we present information about retention and health of a relocated population of gopher tortoises 17 years after relocation. We combine our 17-year postrelocation data with earlier surveys 1 year and 2 years postrelocation to examine whether retention rates change over time. We also evaluate whether retention rates vary by age and gender. Of 74 gopher tortoises relocated in 1985, 31 were present in 2002. We found a 1-year retention rate of 42%, with retention rates of 100% each year thereafter, when we used the percentage of relocated individuals captured at each survey. We found a 1-year retention rate of 73%, a retention rate of 92% from year 1 to year 2, and an overall retention rate of 98.5% from year 2 through year 17, based on the assumption that all individuals present in later surveys were present in earlier surveys. We found no significant difference in retention rate over the 17-year period for adults and juveniles and for adult males and females. Relocated gopher tortoises showed natural growth patterns, indicating good health, but 35% of these gopher tortoises had ≥1 symptom of upper respiratory tract disease, a disease associated elsewhere with population declines of tortoises. Thus, retention rates of relocated gopher tortoises change over time, with relatively low retention during the first year postrelocation but nearly 100% retention in subsequent years. In general, our study shows that relocations can successfully lead to long-term retention of gopher tortoises, but we predict that without management (e.g., fire management and predator control) this relocated population is not viable.     

Evaluation of Techniques for Categorizing Group Membership of White-Tailed Deer

Abstract: We studied sexual segregation, particularly patterns of group membership for white-tailed deer (Odocoileus virginianus), in Lincoln County, Minnesota, USA, to evaluate current techniques used to categorize animals when studying sexual segregation. We categorized group membership according to Hirth (1977) and grouped individuals using our solitary categorization method. Our solitary method was most sensitive to changes in behavior and physiology exhibited by reproductively active females and their association with other deer during sexual segregation.     

Fourteen polymorphic microsatellite loci characterized in the house sparrow Passer domesticus (Passeridae,Aves)

We characterized 14 polymorphic microsatellite loci in the house sparrow Passer domesticus. Four loci were isolated from house sparrow genomic libraries and 10 loci were identified by testing 100 loci that had been originally isolated in other passerine species. Loci were characterized in 37–54 unrelated sparrows from British and Norwegian populations. Each locus displayed between two and 31 alleles, with the observed heterozygosity ranging between 0.30 and 0.91.