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Accurate representations of canopy cover are essential for directing natural resource management efforts targeted at issues such as carbon storage, habitat modeling, fire spread, water resources, and ecosystem services. A two-phase classification approach utilizing an iterative classification of high-resolution aerial imagery to develop training data for a regional-scale classification of percentage woody canopy cover (PWCC) using Sentinel-2 imagery is presented in this study, and is tested for a large portion of South Texas (9,200,000 ha). The modeled PWCC for the study area belonged to the respective classes as follows, PWCC0 = 26%, PWCC90 = 14%, PWCC10 = 12%, PWCC80 = 8%, PWCC20 = 7%, PWCC30 = 7%, PWCC70 = 6%, PWCC50 = 5%, PWCC40 = 5%, and PWCC60 = 5%. Statistics indicated that the overall weighted accuracy for the mapped PWCC classes (Aow) was 0.82 and that the overall weighted kappa ( k w) was 0.49. To demonstrate the usefulness of the PWCC mapping approach to produce reasonable canopy cover estimates, the relative accuracies of modeled PWCC and other similar canopy cover products (LANDFIRE, NLCD) for the study area were summarized. MAE and RSS values were calculated based on five sample areas of directly measured LiDAR canopy cover estimates. The PWCC mapping approach presented here exhibited significantly MAE values for 5 out of 5 sample areas, and lower RSS values for 4 of 5 sample areas. By class MAE and RSS values were lower for all percentage cover classes. Overall, comparisons of the mapping result with high-resolution aerial imagery and the quantitative assessments indicated that the approach presented here was effective for developing highly detailed canopy cover estimates that can be used for planning and modeling at multiple scales (e.g. regional or local). Additionally, this approach can be employed by individual researchers and is less time and resource consumptive when compared to other large scale approaches. To date, only a limited number of existing studies have focused on approaches that can be used to map tree canopy cover for large areas.

Much of the evidence for the evolution of humans has been preserved in caves and rock art that has been found on all the occupied continents. Early human cultures dating back at least 64,000 years to the Neanderthals in southern Europe created basic symbols and hand stencils on cave walls. Isolated indigenous people to this day create works of art on rocks and shelters, but it is the sophisticated paintings of ice-age animals from cave sin France and Spain that have attracted the most study by prehistorians. There are about 340 documented European caves containing art ranging from simple figurines and symbols scratched on the cave walls to complex friezes covering a large wall with many different animals shown in detail. The serious study of these paintings started with the discovery of paintings in Altamira Cave in northern Spain in 1879. Other well-documented art caves from southern France include Lascaux Cave, Chauvet Cave, Niaux Cave, and Cosquer Cave.

Antibody responses were examined among 998 bighorn sheep (Ovis canadensis) in California (USA) to determine spatial patterns of pathogen exposure. Using a shifting frame analysis, a specific geographic region was delineated that contained bighorn sheep with higher (P0.05) levels of multiple exposure (antibodies detected againstor = two pathogens), as well as higher prevalence values for eight of ten individual pathogens. This region in southwestern California encompassed all of the peninsular populations of bighorn sheep recently proposed for listing as endangered by the U.S. Fish and Wildlife Service.

Abstract. Slender mongooses, Herpestes sanguineus , are solitary but males sometimes form loose, non-aggressive associations. Since 1975, sightings of marked animals in the Serengeti National Park, Tanzania, indicate that (1) up to four males may jointly use the same home range, each of which may overlap the ranges of up to six females but no other males; (2) association membership can be stable for up to 7 years; (3) members of an association generally appear on the study site together as young adults, presumably having immigrated from off the study site; and (4) larger associations have persisted for longer periods. DNA fingerprinting confirms that paternity is not monopolized by any single association member, and that association members can be closely related. These results suggest that associations of male slender mongooses are coalitions that exclude other males from access to females within a common territory. Coalitions have also been reported within other mongoose species; this form of escalated mate competition, which has been generally associated only with certain primates and felids, may be more widely distributed.

Abstract. Dwarf mongooses, Helogale parvula, are group-living carnivores in which the oldest male and female dominate reproduction, while subordinates tolerate reproductive suppression and provide care for the offspring of the oldest pair. Subordinates of both sexes, however, mate and subordinate females occasionally become pregnant. In addition, a model of 'power-sharing' in social groups (Vehrencamp 1983, Anim. Behav., 31, 667-682) predicts that dominant individuals should cede some fitness to subordinates, particularly older, higher-ranking individuals not closely related to the dominants, in order to retain them within the group. Human multilocus probes (Jeffreys' 33.15 and 33.6) were used to 'fingerprint' dwarf mongooses from nine different packs in the Serengeti National Park, Tanzania. The results demonstrate that subordinates of both sexes obtain direct fitness: 24% of young had subordinate fathers, while 15% had subordinate mothers. Multiple paternity can occur within a single female's litter. Those subordinates that reproduced were of high social rank and tended to be distantly related to the same-sex dominant, as predicted by Vehrencamp's model. The number of yearlings produced by subordinate females was similar to that predicted by the model. Subordinate males father a relatively high proportion of offspring given their frequency of mating, while subordinate females mate relatively more often than they produce offspring, consistent with previously inferred differences between the mechanisms of male and female reproductive suppression (Creel et al. 1992, Anim. Behav., 43, 231-245). Even though DNA analyses indicate that subordinates produced a substantial proportion of young born in this population, the magnitude of direct fitness obtained by subordinates was still low compared with the magnitude of indirect fitness obtained by helping.

We used spatial autocorrelation of allele frequencies to examine local structure in a population of bannertailed kangaroo rats for which Wright's isolation-by-distance model seems applicable, and for which we can estimate neighborhood size based on 10 years of data on de- mography and dispersal. The uniform dispersion and strong philopatric tendencies of this species provide a test case for the idea that restricted dispersal can lead to local genetic structure in small mammals. Whether we considered such complications as nonnormal dispersal distances, variation in lifetime reproductive success, fluctuating population density, and adult as well as juvenile dispersal, our estimate of effective population size was fewer than 15 animals. Nevertheless, data from four polymorphic allozyme loci analyzed over a range of separations between 50 m (ap- proximately one home range diameter) and 1,000 m detected no evidence for spatial clustering of alleles. One resolution of this apparent paradox is that "gamete dispersal," caused by the movements of males away from their residences during the breeding season, may be a significant (and un- measured) component of gene dispersal. Our analyses alsa demonstrate that a decline in population density may actually increase neighborhood size. A more general implication is that even extremely philopatric mammals have effective population sizes large enough to prevent the development of local genetic structure.

A morphometric study of Psoroptes spp. mites was conducted to address difficulties encountered in species identification and to provide insights into the phylogenetic relationships between mites found on different hosts. A discriminant analysis employing 9 morphologic characters revealed that the lengths of the outer opisthosomal setae and the lateral margins of the opisthosomal knobs were the 2 most important characters for grouping mites according to host species. This analysis clearly separated mites collected from allopatric populations of bighorn sheep, rabbits, and cattle into discrete groups. However, differences were not detected between mites collected from sympatric populations of infested mule deer and bighorn sheep, suggesting that these mites were not host specific and represented a single interbreeding population. Differences also were not detected among mites collected from the ears and body of bighorn sheep and rabbits, demonstrating that the location of mites on a given host should not be used as a primary criterion in species identification.

La variation des allozymes a ete etudiee chez D.s, dans deux populations afin d'examiner le niveau d'heterogeneite genetique intra et inter-population suite a de courtes distances de dispersion des 2 sexes

The woody vegetation and associated soil-site variables from a range of upland to swamp sites were measured using 480 0.04 ha plots from Little Black Slough, Goose Pond and Horseshoe Lake in Illinois, and Mingo Wildlife Refuge, Missouri. Multiple regression, correlation, and factor analysis were used to relate soil-site data to vegetation structure and composition. Coenoclines of both the understory and overstory were constructed to represent the upland-swamp vegetation gradient of the region near the northern terminus of the southern floodplain forest. Percent sand, depth of flooding, and silt content were variables most strongly related to the understory coenocline. Depth of flooding, and clay content were most strongly related to the overstory coenocline. Beta diversities of the understory and overstory coenoclines were 5.8 and 6.9HC. Understory density and overstory basal area increased and species richness and heterogeneity decreased along the upland-swamp gradient. Classification techniques identified three or four major overstory vegetation types within each study area. The 15 overstory types were ordinated and environmental characteristics summarized for each. Mingo Wildlife Refuge had the least flooding and lowest soil clay content. Classification of all 480 plots from the four study areas identified three major understory groups (mesic, floodplain and swamp) and eight overstory groups. These eight include aQuercus velutina-Q. alba, Quercus rubra-Q. alba, Liquidambar styraciflua-Ulmus americana, Quercus phellos-Q. palustris, Quercus lyrata-Acer rubrum, Acer rubrum-Nyssa aquatica, Nyssa aquatica-Taxodium distichum and aTaxodium distichum-Nyssa aquatica type arranged from upland to swamp.

We report natal dispersal distances for 331 banner—tailed kangaroo rats (Dipodomys spectabilis) at high and low population density. The data were collected in 29 censuses of marked individuals in two populations over 8 yr. One population underwent four—fold variation in density. The other was consistently at high density. Because the number of burrow systems (i.e., breeding sites) remained fairly constant, we interpret changes in density as changes in degree of habitat saturation. Dispersal distances were shorter and the proportion of philopatric young (moving less than a home range diameter) was greater at high density than at low density. This result does not conform to models of dispersal based on studies of cycling small mammals or to a simple competition model of dispersal. All data are consistent with a habitat saturation model, which holds that high—density saturated conditions favor philopatric tendencies in offspring. See full-text article at JSTOR