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Patterns of maternal expenditure in Plains bison (Bison bison bison) are equivocal, with different studies yielding conflicting results. Therefore, our objective was to investigate the unsettled question of differential maternal expenditure in Plains bison. By observing the nursing behavior of known age calves, we measured post birth maternal expenditure on sons and daughters between birth and 3 mo of age. Calf weights at 6 mo of age also were measured. Because male calves grow faster and are larger than females as adults, we predicted sons would attempt to acquire more energy via differential nursing behavior and would be heavier at 6 mo of age. The results of our t-tests revealed no significant differences between sons and daughters in any nursing behavior. Male calves, however, performed all behaviors approximately 12% (range 8–20%) more frequently than female calves. For example, despite the nursing attempts of sons being rejected nearly 13% more often than that of daughters, sons nursed about 10% more frequently and 9% longer than daughters did. This occurred despite mothers terminating nursing bouts equally for both sexes. Therefore sons appear to demand (and obtain) more energy from mothers than daughters. [ABSTRACT FROM AUTHOR]

We investigated if relative abundance of invertebrate prey for Athene cuniculariafloridana (Florida Burrowing Owl) differed between two pre-translocation (i.e., non-mined) sites and one translocation (i.e., reclaimed mine) site. We trapped a combination of 21 arthropod families and orders. We observed some differences among non-mined sites and the reclaimed mine site in invertebrate prey abundance and owl diet. Fewer than 50% (10 of 21) of trapped prey items were present in pellets, suggesting that our traps may have limited capture of particular prey. Additionally, it appears that owls were hunting in nearby aquatic habitats due to the remains of frogs, turtles, and crayfish in pellets. The general similarity in prey abundance and diet between the pre-translocation and translocation sites suggests that reclaimed mine sites may serve as adequate refugia for Florida Burrowing Owls. However, more work is needed to determine to verify the general applicability of our results. [ABSTRACT FROM AUTHOR]

Abstract: Since 1994 wild vicuñas have been captured and shorn for their wool, yet, there remains a noticeable lack of data regarding the possible influence of capture and shearing upon vicuña biology. Therefore, we assessed post-capture group composition, genetic relatedness, and paternity among animals that were captured for live shearing and release. We captured twenty-six groups (134 animals) on the Chilean Altiplano. Seventy-three percent of Male Groups (designated prior to chase) contained exclusively adult males upon capture, whereas remaining “Male Groups” contained crias and/or adult females and crias. Forty-seven percent of Family Groups (designated prior to chase) contained 1 adult male, adult females, and the number of crias≤the number of adult females. Remaining Family Groups contained no or multiple adult males, and more crias than adult females. Average relatedness among all vicuñas was −0.007. Paternity analysis revealed that 35% of crias were captured with their biological mother and that only 1 cria was captured with both biological parents. Based on previous observations of group composition in the wild, animals from different groups may separate and/or mix during the chasing stage. Improvement of the chasing technique and instituting a post-capture monitoring program may aid in the detection of medium- and long-term impacts regarding group stability, cria survival, and ultimately wool production. [Copyright &y& Elsevier]

One behavioral tactic that juvenile mammals can use to resolve conflict with adults is the reversion to behaviors of an earlier developmental stage. Therefore, we examined the appearance, body posture, and ontogenetic differences of submissive crouch behavior between juvenile male and female guanacos from birth to 9 months of age in Tortes del Paine National Park, Chile. On average, submissive crouches appeared 73 days after birth, and juvenile males displayed them more frequently than did juvenile females. Juvenile males also displayed more extreme body postures during submissive crouches than did juvenile females. Sex, group size, and season significantly influenced a juvenile's likelihood of displaying a submissive crouch. [ABSTRACT FROM AUTHOR]

Demography and spatial patterns of free-ranging American mink were documented by continuous year-round trapping and radiotracking along 24 km of the River Thames in England, United Kingdom. An estimated average of 7.19 ± 0.58 SE minks per month were present between May 1995 and August 1997. Kit and juvenile paternity was assessed using 7 microsatellite markers and we observed evidence that multiple paternity occurred in this population. Although males maintained territories during most of the year, they sired litters in areas beyond their territory boundaries. We suggest that a male's inability to monopolize paternity, along with a female's ability to continue ovulation after successful matings (i.e., superfetation) explains why males abandon territoriality during the breeding season. We suggest that the main function of a brief delayed implantation of this species may be to enable female mink to retain superfetation, which facilitates the fertilization of ova from different ovulations by different males. This mink model, consisting of disarticulating residency from fatherhood and the possibility of superfetation, may occur more widely among related species and requires a re-evaluation of mustelid sociobiology. [ABSTRACT FROM AUTHOR]

We investigated the distribution, habitat characteristics and conservation value of mating areas in a wild population of guanacos in Torres del Paine National Park, Chile. Copulating guanacos were observed directly during December–January 1994–1995, 1995–1996 and 1997–1998. The timing of the breeding season was homogeneous across years. Copulation sites occurred in vega (ephemeral wetland) habitats (48.6%) greater than expected based on their relative availability (12.6%). A multivariate habitat analysis revealed that habitat composition of breeding habitats differed significantly from non-breeding areas (P <0.001). Availability of trees and shrubs (breeding=5.5%; non-breeding=35.6%; P <0.001) and grassland (breeding=34.6%; non-breeding=9.5%; P <0.001) contributed most to the variation in habitat types among areas. Relative occurrence of pumas was significantly lower in breeding areas (P=0.04). The spatial arrangement of mating sites was similar among years suggesting that adult female and male guanacos exhibited site fidelity to breeding sites. Since vegas were important habitats for mating it is critical that natural resource managers consider the importance of these ephemeral wetland resources to ensure for proper reproduction and viability of local guanaco populations. [Copyright &y& Elsevier]

Focuses on a study which investigated the influence of population density and meteorological conditions on birth mass of guanacos in Chile from 1987 to 1996. Factors affecting mass at birth in wild ungulates; Materials and methods; Results of the study.

Describes the development and characteristics of microsatellite primers designed for the guanaco, Lama guanicoe and their utility for the South American camelids. Isolation of microsatellite loci using a modified non-radioactive capture-hybridization method; Annealing of the biotinylated capture probe to the linkered DNA.

Nectophrynoides asperginis (Bufonidae) is a small toad endemic to the spray zone of the Kihansi River waterfall in Tanzania, Africa. This species was declared extinct-in-the-wild by the International Union for Conservation of Nature (IUCN) following construction of a hydroelectric dam that reduced the flow of the waterfall. The species is now limited to ex situ populations at the Wildlife Conservation Society's (WCS) Bronx Zoo, New York, the Toledo Zoo, Ohio, and two newer facilities in Tanzania. Much of the natural history of N. asperginis remains unknown, though it is known they are a sexually dimorphic species. Typically, males are smaller than females and possess distinctive dorsolateral inguinal patches (IP). Males appear to display these patches to conspecifics, but their function remains unknown. We created a five-grade schema to categorize the IPs by visual prominence accounting for both patch size and color, with Grade 1 being the least and Grade 5 being the most prominent. We hypothesized that a positive association exists between male IP grade and the snout-urostyle length (SUL) of females they amplexed. Therefore, we measured SUL and body mass in 91 pairs of amplexing N. asperginis and assessed the relationship of IP grade to female SUL in the amplexed pairs. Statistical analysis revealed a significant positive correlation (Spearman's rho = 0.250, P = 0.017) between male IP grade and the SUL of females being amplexed. This study suggests that IP grade is associated with mate assortment in N. asperginis, and it represents one of the first glimpses into the complex social interactions of this extinct-in-the-wild amphibian. [ABSTRACT FROM AUTHOR]

We investigated patterns of maternal expenditure and its influence on juvenile survival in the polygynous monomorphic guanaco (Lama guanicoe) in southern Chile from 1990 to 1994. Birth weight and growth rate (until age 1) of males and females were similar. Suckling rates of males and females were not significantly different, although mothers of males rejected suckling attempts more often than mothers of females during fall and winter. Mothers with sons terminated suckling boutsin equal proportion as did mothers with daughters. Our estimated level of reproductive effort for guanacos falls within the range of species exhibiting no sex-biased maternal expenditure on offspring. Mean yearly birth weight was negatively correlated with population density. Mean suckling time throughout the year differed among cohorts, as did the mean number of suckling attempts and rejected suckling attempts per hour throughout the year. Juvenile survival was estimated untilage 1. Of the models with five covariates including juvenile sex, birth weight, adult female aggression toward taggers, mean suckling time, and population density, only mean suckling time and population density were significantly related to survival. The risk ratio for mean suckling time indicates that the risk of mortality increases as suckling time increases, whereas the risk ratio for population density indicates that the risk of mortality decreases as population density increases. Under some conditions increasing population density may be correlated with lower offspring birth weight, yet enhanced juvenile survival. This effect on survival was possibly associated with the number of predators on the study area from year to year. [ABSTRACT FROM AUTHOR]

Summary 1. The Chilean National Forestry and Park Service is striving to implement a guanaco management programme of sustained-yield use. To achieve this, the rate, variation and causes of juvenile guanaco mortality must be understood thoroughly. Therefore, we monitored the survival of 409 radio-collared juvenile guanacos in Torres del Paine National Park, Chile, from 1991 to 1996. 2. The Kaplan–Meier product limit estimator of survival for staggered entry was calculated, and survival rates between juvenile males and females and among years were compared using the lifetest procedure in SAS. The Cox proportional hazards model was used to relate mortality rate to explanatory variables such as juvenile sex, birth weight, adult female aggression towards researchers during the capture and tagging of newborns, population density, and mean monthly winter snowfall. 3. Mean juvenile survival rate (ŝ) was 0·38, but varied between 0·31 and 0·55. Survival rates between the sexes were not significantly different, although male survival was lower than that of females. Mortality rate was highest during the first 14 days after birth. Most deaths occurred between birth and 7 months of age. 4. The risk of mortality increased by almost 6% with every 1 cm increase in winter snowfall, whereas the risk of mortality decreased by almost 24% as adult female aggression increased towards researchers. 5. Current management objectives are aimed at the implementation of a rational harvest of guanacos on the Chilean side of the island of Tierra del Fuego. Our results provide improved and updated estimates of juvenile guanaco survival and will aid in the modelling of harvest rates of guanacos in southern Chile. Future proposed harvests from wild populations in southern Chile need to consider the rate and variation of this critical life-history parameter. [ABSTRACT FROM AUTHOR]

The article focuses on a study which involved the statewide distribution and habitat use of Florida Burrowing Owl (Athene cunicularia floridana) in remote, nonurban areas. Researchers visited Burrowing Owl sites from historical databases followed by the quantification of land cover within empirically-derived distances around burrows which have confirmed or probable breeding activity. It is believed that the result of the quantification can help wildlife managers in understanding habitat usage in nonurban areas. According to the researchers, there is a need for increased surveys and conservation efforts in nonurban areas in addition to enhanced cooperation with landowners.

The article presents a study which compares the availability of prey and diet to Florida Burrowing Owls in urban and rural areas. The study determined the differences in the owl's ecology in rural and urban areas in the basis of analysis of pellets, insects and arachids which is the frequent food of the species. It cites that this is the first comparison of prey and diet available for owl populations in urban and rural areas.

The extent and geographic patterns of molecular genetic diversity of the largest remaining free-ranging cheetah population were described in a survey of 313 individuals from throughout Namibia. Levels of relatedness, including paternity/maternity (parentage), were assessed across all individuals using 19 polymorphic microsatellite loci, and unrelated cheetahs (n = 89) from 7 regions were genotyped at 38 loci to document broad geographical patterns. There was limited differentiation among regions, evidence that this is a generally panmictic population. Measures of genetic variation were similar among all regions and were comparable with Eastern African cheetah populations. Parentage analyses confirmed several observations based on field studies, including 21 of 23 previously hypothesized family groups, 40 probable parent/offspring pairs, and 8 sibling groups. These results also verified the successful integration and reproduction of several cheetahs following natural dispersal or translocation. Animals within social groups (family groups, male coalitions, or sibling groups) were generally related. Within the main study area, radio-collared female cheetahs were more closely interrelated than similarly compared males, a pattern consistent with greater male dispersal. The long-term maintenance of current patterns of genetic variation in Namibia depends on retaining habitat characteristics that promote natural dispersal and gene flow of cheetahs. [ABSTRACT FROM AUTHOR]

We present the first use of necklace radio transmitters to document the home range and dispersal of juvenile Burrowing Owls (Athene cunicularia floridana) during the breeding and post-breeding period in rural Florida. Juvenile Burrowing Owls (n = 4) were detected close to main and satellite burrows during 65 day-time relocations. Home range estimates (95% kernel) for juvenile owls varied from 98 to 177 m². Juvenile Burrowing Owls were not detected near main and satellite burrows during three evening relocations. Dispersal of juvenile owls coincided with flooding of burrows during the rainy season. Juvenile owls upon fledging used an extensive patch of saw palmetto (Serenoa repens) before dispersing beyond the range of ground telemetry capabilities. Aerial telemetry assisted in locating one juvenile Burrowing Owl using scrub oak (Quercus spp.) habitat approximately 10.1 km southeast of its main and satellite burrows. [ABSTRACT FROM AUTHOR]

Studies the early mortality of newborn guanacos by birth mass and hematological parameters. Methodology used; Percentage of newborn guanacos that died within 10 days of life; Results of the study.

Ecosystem engineers create physical changes in abiotic and biotic material, and through this process control the availability of resources for other species. Predators that abandon large portions of their prey may be ecosystem engineers that create habitat for carrion-dependent invertebrates that utilize carcasses during critical life-history periods. Between 04-May-2016 and 04-Oct-2016, we sampled beetle assemblages at 18 carcasses of prey killed by pumas and matching control sites in the southern Greater Yellowstone Ecosystem, USA, to measure the extent to which beetle families utilized these carcass "habitats". We used generalized linear-mixed models and linear-mixed effect models to examine changes in beetle abundance, species richness, and Simpson's Index of Diversity. We estimated kill rates and carrion production rates for individual pumas to better assess the impact of pumas on invertebrate communities. We collected 24,209 beetles representing 215 species. We identified eight beetle families that had significantly higher abundance at carcasses than control sites. Carcasses had a statistically large to very large effect (determined using Cohen's d) on beetle abundance, richness, and diversity for the initial 8 weeks of sampling. Our research revealed strong effects of an ecosystem engineer on beetle assemblages while highlighting the potential role of apex predators in creating and modifying physical habitats for carrion-dependent species. This suggests that there may be consequences for invertebrate communities where apex predators exist at reduced numbers or have been eradicated. The ecological role of invertebrates is often overlooked, yet they are essential taxa that provide critical ecological services upon which we depend. [ABSTRACT FROM AUTHOR]

We compared injuries resulting from two different capture methods, i.e. trailing hounds and foot snares, for pumas Puma concolor in a mixed landscape with open grasslands and limited 'retreat' habitat in southern Chilean Patagonia. Injury scores were not significantly different for the two methods, although the small sample size for captures made with snares likely influenced our findings. Based on a potential range of 0-400, the mean injury score for pumas caught using hounds was 56.3 6 132.9 (SD). The mean puma injury score for five animals caught in snares was 3.8 6 1.1. Pumas were injured and/or killed in 86% of captures using trailing hounds. The number of hounds used in a capture attempt did not predict the likelihood of successfully catching a puma (P=0.35), whereas there was a strong relationship between the number of dogs and the likelihood of a fight with the puma (P<0.0001). The odds ratio calculation predicted a 14.7%increase in the likelihood of a fight between puma and hounds with the addition of each dog to the chase. Our results highlight the potential risks associated with trailing hounds in open landscapes. We suggest guidelines for the use of hounds in predominantly open landscapes, and that alternative capture methods such as foot snares should be considered as a potentially safer alternative. Lastly, we make recommendations for the development of injury assessment systems more relevant to catch-and-release research. [ABSTRACT FROM AUTHOR]

Predator tourism is one strategy to improve tolerance for predators, and support biodiversity and ecosystem health. Torres del Paine National Park (TdP) – a UNESCO Biosphere Reserve in southern Chile - supports productive livestock industries and nascent puma tourism. We compared interviews conducted in the region prior to puma tourism, with results from interviews collected across 45 ranches post-puma tourism. We assessed rancher attitudes regarding pumas, puma-livestock conflict, puma tourism, and linked them with socio-ecological factors. Respondents who viewed pumas as a threat experienced higher livestock losses. Respondents who reported higher sheep losses were inclined to support the lethal removal of livestock-killing pumas, and to initiate a puma hunt, whereas respondents who supported puma tourism disagreed with hunting pumas. Using the Potential for Conflict Index, we found that participants exhibited the highest consensus on the benefit of puma tourism and the lowest consensus over lethal removal of pumas. Our results suggest predator tourism has increased tolerance for pumas but is creating new potential for conflict. Previous to puma tourism, ranchers were almost entirely negative about pumas and unanimously supported illegal puma hunting. Now, most believe that pumas are part of Patagonia's heritage. This divide was best explained by distance to TdP: ranches closer to TdP experienced greater losses to pumas but had neighbours that benefitted most from puma tourism. Therefore, we suggest that tourism revenues supplement community compensation insurance programs that reimburse rancher losses to pumas to mitigate the growing divide between those benefiting from pumas and those experiencing economic hardship. • Predator tourism has increased tolerance for pumas, but is creating new potential for conflict among ranchers. • Respondents who reported higher sheep losses were inclined to support the lethal control of livestock-killing pumas. • Respondents who supported puma tourism disagreed with hunting pumas. • Ranches closer to the National Park benefitted most from puma tourism but had neighbours that suffered the greatest costs. [ABSTRACT FROM AUTHOR]