Capture recapture

We present data on capture and recapture of neotrop- ical migrants at constant-effort mist net sampling lo- cations in Utah between 1994 and 2002. Data were collected in accordance with MAPS (Monitoring Avian Productivity and Survivorship) protocols. Since 1994, a total of 23,789 birds have been captured (i.e., total cap- tures include new captures, recaptures, and unbanded individuals) representing 149 species. Data collected thus far provide some measure of site fidelity and long- evity for species breeding in and migrating through Utah. Of the 18,358 birds banded, 2,367 (12.9 percent) were subsequently recaptured at least once. The longest interval between initial capture and recapture was over eight years. Assessments of subcutaneous fat carried by each bird captured were also made in accordance with MAPS protocols. Using Yellow Warbler (Dendroica petechia) as an example, we calculated an estimated maximum travel distance (EMTD) that migrants can fly from Utah on the energy deri...

SUMMARY Capture-recapture methodology, originally developed for estimating demographic parameters of ani- mal populations, has been applied to human populations. This tutorial reviews various closed capture- recapture models which are applicable to ascertainment data for estimating the size of a target population based on several incomplete lists of individuals. Most epidemiological approaches merging di;erent lists and eliminating duplicate cases are likely

The oak decline is probably the most severe plant health problem faced in the Mediterranean region which is one of the habitats of community interest under the EU’s environmental legal regime. More information on the role of Cerambycids species in this decay is still needed. This paper reports the apparent survival rate (Phi) and recapture rate (P) for a population of Cerambyx welensii Küster (Coleoptera cerambycidae) in a highly degraded cork oak grove near the Doñana National Park (Huelva, Spain) as calculated using the mark-capture-recapture method. High and constants in the time values of apparent survival rates for males and females are detected. The male overall recapture rate (P) exceeded that of the female group with relatively low, but significant, values. The presence of transient individuals suggests a nucleus of population with many immigrants and emigrants in the study plot. The results are used to discuss various aspects of the insect biology, and the potential effect of the gradual deterioration of the studied ecosystem on theinsect population it supports.

�A b s t r a c t. Roads and highways represent one of the most important anthropogenic impacts on natural areas and contribute to habitat fragmentation, because they are linear features that can inhibit animal movement, thereby causing barrier effects by subdividing the populations adjacent to the roads. The study presented here aims to determine, to which extent roads act as a barrier, subdividing populations of three species of small forest mammals: bank vole, yellow-necked mouse and common shrew, and what is the relative importance of road width and traffic intensity on the barrier effect. The study was carried out at four �25 m long segments of roads, close to the city of ceske Budějovice. All segments crossed a forest. The capture-recapture method was applied to determine the crossing rates of animals. The traps were checked three times each day during four consecutive nights, in summer and in autumn. We found that: (�) roads strongly prevent crossing movements in all three stu...

Differences in alpha and beta bat diversity among montane rainforest and five shaded coffee plantations under different management regimes, as well as some environmental factors and vegetation parameters influencing bat richness, were evaluated for the first time in southeastern Chiapas, Mexico. In each site, bats were captured every 2 months from March 2004 to July 2005, with six mist-nets, during two nights, using the capture–recapture method. We captured 2970 individuals of 43 bat species. Montane rainforest had the greatest alpha diversity (H′ = 2.681; n = 37), whereas alpha diversity was similar among coffee plantations (H′ = 2.229–2.364; n = 23–26). The number of frugivorous and nectarivorous species was similar among the sites; the greatest exchange in species composition (beta diversity) occurred for insectivorous bats, which reduce their number in coffee plantations as pesticides are incorporated. Bat richness species was significantly related to the number of vegetation strata, height, and cover of trees. We suggest that coffee plantations could act as corridors, facilitating connection among different elements of the landscape in the Sierra Madre de Chiapas for some frugivorous and nectarivorous bats.

Conservation strategies for endangered species require accurate and precise estimates of abundance. Unfortunately, obtaining unbiased estimates can be difficult due to inappropriate estimator models and study design. We evaluate population–density estimators for tigers Panthera tigris in Kanha Tiger Reserve, India, using camera traps in conjunction with telemetry (n=6) in a known minimum population of 14 tigers. An effort of 462 trap nights over 42 days yielded 44 photographs of 12 adult tigers. Using closed population estimators, the best-fit model (program capture) accounted for individual heterogeneity (Mh). The least biased and precise population estimate ( (SE) []) was obtained by the Mh Jackknife 1 (JK1) [14 (1.89)] in program care-2. Tiger density ( (SE) []) per 100 km2 was estimated at 13 (2.08) when the effective trapping area was estimated using the half mean maximum distance moved (1/2 MMDM), 8.1 (2.08), using the home-range radius, 7.8 (1.59), with the full MMDM and 8.0 (3.0) with the spatial likelihood method in program density 4.1. The actual density of collared tigers (3.27 per 100 km2) was closely estimated by home-range radius at 3.9 (0.76), full MMDM at 3.48 (0.81) and spatial likelihood at 3.78 (1.54), but overestimated by 1/2 MMDM at 6 (0.81) tigers per 100 km2. Sampling costs (Rs. 450 per camera day) increased linearly with camera density, while the precision of population estimates leveled off at 25 cameras per 100 km2. At simulated low tiger densities, a camera density of 50 per 100 km2 with an effort of 8 trap nights km−2 provided 95% confidence coverage, but estimates lacked precision.

Cette etude se place dans le contexte des maladies infectieuses emergentes maintenant reconnues comme une menace majeure de la biodiversite. Engendrant un taux de mortalite atteignant 95 %, les epidemies a virus Ebola ayant affecte les populations de gorilles de plaine de l'Ouest (Gorilla gorilla gorilla) conduisirent a la classification de ce taxon comme " En danger critique d'extinction ". Cette etude s'interesse aux capacites de recuperation de ses populations. Grâce a des donnees uniques d'observation en phase pre- et post-epidemique, nous avons evalue l'impact de l'epidemie sur la structure et la dynamique sociale d'une population et estime son potentiel de recuperation au cours des six ans qui ont suivi. Nos resultats de demographie et de dynamique, couples a des approches statistique et de modelisation demographique detaillee au niveau des classes d'âge et de sexe, et integrant l'immigration, nous ont permis de mettre en evidence ...

Road traffic injuries are a major cause of preventable death in sub-Saharan Africa. Accurate epidemiologic data are scarce and under-reporting from primary data sources is common. Our objectives were to estimate the incidence of road traffic deaths in Malawi using capture-recapture statistical analysis and determine what future efforts will best improve upon this estimate. Our capture-recapture model combined primary data from both police and hospital-based registries over a one year period (July 2008 to June 2009). The mortality incidences from the primary data sources were 0.075 and 0.051 deaths/1000 person-years, respectively. Using capture-recapture analysis, the combined incidence of road traffic deaths ranged 0.192–0.209 deaths/1000 person-years. Additionally, police data were more likely to include victims who were male, drivers or pedestrians, and victims from incidents with greater than one vehicle involved. We concluded that capture-recapture analysis is a good tool to est...

SUMMARY We present here an assessment of trends in abundance of humpback whales in the North Atlantic Ocean based upon capture–recapture estimates of abundance using naturally marked individuals. A total of 24 estimates was calculated spanning 14 years. ...