The physiological and behavioural impact of, as well as preference for, enriched versus barren environments was determined for captive eastern box turtles (
Terrapene carolina carolina). Thirty-eight ...box turtles were randomized to either barren (flat newspaper substrate) or enriched (cypress mulch substrate, shredded paper and a hide box) enclosures for a 1-month period. Complete blood counts, fecal corticosterone, and body weights were measured at the beginning and end of the test period. Activities performed within the two environments were also compared.
Turtles in enriched enclosures had a significantly lower heterophil to lymphocyte ratio (H/L) at the end of the treatment period (
p
=
0.01). Enriched-housed turtles also spent significantly less time engaged in escape behaviour (
p
<
0.01). There was no significant difference in fecal corticosterone or body weight change between the two treatment groups.
At the beginning of the study, each turtle was placed in a preference test system in which it could move freely between a barren and enriched environment. Relative-dwelling time (RDT) was determined for each environment. Turtles showed a distinct preference for the enriched environment (90.9% median RDT,
p
<
0.01). After the 1-month housing experiment turtles were revaluated for preference to determine if previous housing experience affected choice. Turtles continued to prefer an enriched environment regardless of prior housing conditions (97.6% median RDT,
p
<
0.01).
Results of this study demonstrate that the captive housing environment impacts the physiology and behaviour of box turtles, and suggest housing modifications that encourage typical species-specific behaviour should be provided.
Accurate understanding of habitat quality is a critical component of wildlife management. We developed a definition of high-quality foraging habitat for the red-cockaded woodpecker (Picoides ...borealis), a federally endangered, cooperatively breeding bird species, from analyses of resource selection and habitat use, relationships between fitness measures and habitat features, and an extensive literature review. In the North Carolina Sandhills, use of foraging habitat at the level of individual trees, habitat patches, and forest stands was strongly and positively related to age and size of pines (Pinus spp.). Use of habitat patches and forest stands was greatest at intermediate densities of medium-sized and large pines and was negatively associated with hardwood and pine midstory. Size of red-cockaded woodpecker groups, an important fitness measure for this species, was positively related to density of old-growth pines within the home range and negatively related to density of medium-sized pines and height of hardwood midstory. Similar results were reported by 2 other studies. High-quality foraging habitat for red-cockaded woodpeckers, therefore, contains sparse or no midstory, intermediate densities of medium-sized and large pines, and old-growth pines in at least low densities. Although we documented a relationship between group size and the amount of habitat meeting our definition of "high quality," we were unable to identify the optimum amount of high-quality habitat to provide per group because most study groups had relatively little high-quality foraging habitat. Both fitness and habitat selection in our study population may be constrained by quality and quantity of foraging habitat. James et al. (2001) recommended, and we strongly agree, that foraging habitat be managed for abundant herbaceous ground cover, low densities of small and medium-sized pines, and moderate densities of large pines. We also stress the importance of old-growth pines in foraging habitat. Because the structure of high-quality foraging habitat is similar to that of high-quality nesting habitat, we recommend that management of these 2 be increasingly integrated.
Roads pose many threats to wildlife including wildlife–vehicle collisions, which are a danger to humans as well as wildlife. Bridges built with provisions for wildlife can function as important ...corridors for wildlife passage. We used video surveillance to record wildlife passage under a bridge near Durham, North Carolina, USA, to determine whether it functioned as a wildlife underpass. This is particularly important for white-tailed deer (Odocoileus virginianus) because forests associated with the bridge created a corridor between 2 natural areas. We calculated detection probabilities and estimated the number of crossings as observed crossings divided by detection probability. We observed 126 crossings by >10 species of mammals. Detection probability was 42%; therefore, an estimated 299 wildlife crossings occurred. We observed 75 deer: 17 deer approached the underpass and retreated. We estimated sighting 40% of deer crossings and 92% of deer approaches. Thus, an estimated 185 deer crossings and 18 approaches occurred. As an index of road mortality, we conducted weekly surveys of vehicle-killed animals on a 1.8-km section containing the underpass. We discovered only 5 incidences of animals killed by vehicles. The size and design of the bridge promoted wildlife use of the underpass, providing landscape connectivity between habitats on opposite sides of the highway and likely increasing motorist safety. Thus, bridges in the appropriate landscape context and with a design conducive to wildlife use, can function as a corridor to reduce the effects of fragmentation.
Summary Background Postoperative surgical site infections are one of the most frequent complications after open abdominal surgery, and triclosan-coated sutures were developed to reduce their ...occurrence. The aim of the PROUD trial was to obtain reliable data for the effectiveness of triclosan-coated PDS Plus sutures for abdominal wall closure, compared with non-coated PDS II sutures, in the prevention of surgical site infections. Methods This multicentre, randomised controlled group-sequential superiority trial was done in 24 German hospitals. Adult patients (aged ≥18 years) who underwent elective midline abdominal laparotomy for any reason were eligible for inclusion. Exclusion criteria were impaired mental state, language problems, and participation in another intervention trial that interfered with the intervention or outcome of this trial. A central web-based randomisation tool was used to randomly assign eligible participants by permuted block randomisation with a 1:1 allocation ratio and block size 4 before mass closure to either triclosan-coated sutures (PDS Plus) or uncoated sutures (PDS II) for abdominal fascia closure. The primary endpoint was the occurrence of superficial or deep surgical site infection according to the Centers for Disease Control and Prevention criteria within 30 days after the operation. Patients, surgeons, and the outcome assessors were masked to group assignment. Interim and final analyses were by modified intention to treat. This trial is registered with the German Clinical Trials Register, number DRKS00000390. Findings Between April 7, 2010, and Oct 19, 2012, 1224 patients were randomly assigned to intervention groups (607 to PDS Plus, and 617 to PDS II), of whom 1185 (587 PDS Plus and 598 PDS II) were analysed by intention to treat. The study groups were well balanced in terms of patient and procedure characteristics. The occurrence of surgical site infections did not differ between the PDS Plus group (87 14·8% of 587) and the PDS II group (96 16·1% of 598; OR 0·91, 95% CI 0·66–1·25; p=0·64). Serious adverse events also did not differ between the groups—146 of 583 (25·0%) patients treated with PDS Plus had at least one serious adverse event, compared with 138 of 602 (22·9%) patients treated with PDS II; p=0·39). Interpretation Triclosan-coated PDS Plus did not reduce the occurrence of surgical site infection after elective midline laparotomy. Innovative, multifactorial strategies need to be developed and assessed in future trials to reduce surgical site infections. Funding Johnson & Johnson Medical Limited.
The evolution of delayed dispersal and reproduction in cooperative breeders can be viewed as selection between alternative life-history tactics: (1) stay-and-foray (SAF), in which individuals delay ...dispersal and reproduction and compete for breeding vacancies in the vicinity of the natal territory, and (2) depart-and-search (DAS), in which individuals disperse soon after fledging to wander in search of a breeding vacancy. Using demographic data collected from red-cockaded woodpeckers (Picoides borealis), we evaluated a demographic model of the evolution of delayed dispersal and reproduction based on selection between these tactics. Because males of this species exhibit both tactics regularly, we could estimate all model parameters directly. Our estimates provide empirical support for key assumptions of demographic models of the evolution of delayed dispersal and reproduction, such as a disparity in survival between those adopting SAF and those adopting DAS during the first year of life, a low rate of successful dispersal in those practicing DAS, and low reproductive success at early ages among breeders. We show, in a population in which the fate of dispersers could be documented, that the fitness of individuals delaying dispersal and reproduction can equal or exceed that of individuals attempting early reproduction, even without indirect fitness benefits due to helping behavior.
We used cohort analyses and population cohort matrices to model a wild turkey (Meleagris gallopavo silvestris) population under perturbed (i.e., man-induced flooding on 3-yr intervals) and ...unperturbed (i.e., non-flood) conditions. The net reproductive rate$(R_{o})$of a cohort in which reproduction in the hatching-year (HY) age class was perturbed by flooding dropped to 0.460 from Ro= 1.383 for unperturbed cohorts. The Roof cohorts in which only after-hatching-year (AHY) age classes were exposed to flooding was >1.0. Cohort analyses demonstrated the importance to the population of nesting by HY hens and the significant effects on cohort reproductive potential of exposing the HY age class to flooding. Evaluation of population cohort matrices also suggested that flooding on a 3-year interval precludes sufficient reproduction to maintain this wild turkey population.
Serum samples and choanal cleft swabs were collected from livetrapped and hunter killed wild turkeys (Meleagris gallopavo) from Martin and Bertie counties, North Carolina (USA). Sera were tested for ...antibodies to Mycoplasma gallisepticum, Mycoplasma synoviae and Mycoplasma meleagridis by hemagglutination inhibition (HI). Sera from 33% (five of 15) of livetrapped turkeys were positive for antibodies to M. gallisepticum by HI, and all were negative for antibodies to M. synoviae and M. meleagridis. Choanal cleft swabs from 22 livetrapped and five hunter killed wild turkeys cultured in Frey's broth medium resulted in 23 mycoplasma isolations. Using direct immunofluorescence, 74% (17/23) were M. gallopavonis, and 26% (six of 23) were unidentified; no isolate was identified as M. gallisepticum, M. synoviae or M. meleagridis.
Understanding the habitat requirements of red-cockaded woodpeckers (Picoides borealis), an endangered species that continues to decline in the southeastern United States, is crucial to successfully ...reversing this trend. We developed a discriminant function using habitat characteristics within 0.25 mile (0.4 km) of the cluster center as independent variables and a demographic measure of fitness as the dependent variable to model habitat quality for 29 red-cockaded woodpecker groups in the North Carolina Sandhills. The best fit model, which included number of cavities, average diameter of overstory pines, and average understory height, correctly classified 23 of 29 sites. Mean values for good and poor sites were: number of cavities, 6.5 and 3.7; pine diameter at breast height (dbh), 35.0 cm (13.8 in) and 38.1 cm (15.0 in); and understory height, 1.89 m (6.2 ft) and 3.26 m (10.7 ft), respectively. Our management recommendations developed from this study include ≥7 cavities/group, average pine overstory >20 cm (8 in) dbh, and average understory height <1.8 m (6 ft) throughout nesting and foraging habitat.
We calculated a genetically based minimum viable population size of the red-cockaded woodpecker (Picoides borealis) using a formula derived from Hill (1972) and life history data from a long-term ...study. Based on published criteria for maintenance of genetic variability, a red-cockaded woodpecker population must contain 509 breeding pairs to be considered viable. It is likely that no existing population contains 509 breeding pairs. Genetically based estimates of population viability may not be valid, but if they are adopted as in the recovery plan for the red-cockaded woodpecker, the area required for a viable population would be ≥25,450 ha. The estimates of population size and area required for a viable population are considerably higher than those contained in the species' recovery plan (U.S. Fish and Wildl. Serv. 1985).
