Maternal effects on anogenital distance in a wild marmot population

Peer reviewedPublisher PD

Effectiveness of habitat management in the recovery of low-density populations of wild rabbit.

Understanding the relationship between spatial patterns of landscape attributes and population presence and abundance is essential for understanding population processes as well as supporting management and conservation strategies. This study evaluates the influence of three factors: environment, habitat management, and season on the presence and abundance of the wild rabbit (Oryctolagus cuniculus), an important prey species for Mediterranean endangered predator species. To address this issue, we estimated wild rabbit presence and abundance by latrine counting in transects located in 45 plots within a 250×250 m grid from June 2007 until June 2009 in a 1,200 ha hunting area in southern Portugal.We then analyzed how wild rabbit presence and abundance correlatewith the aforementioned factors. Our results showed that the main variable influencing wild rabbit presence and abundance was the distance to the artificial warrens. North and northeast slope directions were negatively related to wild rabbit presence. Conversely, rabbit presence was positively correlated with short distances to ecotone, artificial warrens, and spring. Regarding rabbit abundance, in addition to artificial warrens, soft soils, bushes, and season also had a positive effect. We found that environmental variables, management practices, and season each affect wild rabbit presence and abundance differently at a home range scale in low-density population. Thus, our major recommendations are reducing the distance to artificial warrens and ecotone, ideally to less than 100 m, and promoting habitat quality improvement on slopes with plenty of sun exposure

Environmental effects and individual body condition drive seasonal fecundity of rabbits: identifying acute and lagged processes

The reproduction of many species is determined by seasonally-driven resource supply. But it is difficult to quantify whether the fecundity is sensitive to short- or long-term exposure to environmental conditions such as rainfall that drive resource supply. Using 25 years of data on individual fecundity of European female rabbits, Oryctolagus cuniculus, from semiarid Australia, we investigate the role of individual body condition, rainfall and temperature as drivers of seasonal and long-term and population-level changes in fecundity (breeding probability, ovulation rate, embryo survival). We built distributed lag models in a hierarchical Bayesian framework to account for both immediate and time-lagged effects of climate and other environmental drivers, and possible shifts in reproduction over consecutive seasons. We show that rainfall during summer, when rabbits typically breed only rarely, increased breeding probability immediately and with time lags of up to 10 weeks. However, an earlier onset of the yearly breeding period did not result in more overall reproductive output. Better body condition was associated with an earlier onset of breeding and higher embryo survival. Breeding probability in the main breeding season declined with increased breeding activity in the preceding season and only individuals in good body condition were able to breed late in the season. Higher temperatures reduce breeding success across seasons. We conclude that a better understanding of seasonal dynamics and plasticity (and their interplay) in reproduction will provide crucial insights into how lagomorphs are likely to respond and potentially adapt to the influence of future climate and other environmental change.Konstans Wells, Robert B. O’Hara, Brian D. Cooke, Greg J. Mutze, Thomas A.A. Prowse, Damien A. Fordha

Diurnal pattern of pre-weaning den visits and nursing in breeding pairs of captive dingoes (Canis dingo)

The period before pups are weaned represents a key developmental stage for canids that is directly related to the survivability of the pack. Yet our understanding of the role of the parents during this period when pups are confined to a den is rather limited. We sought further insight into this period by observing diurnal patterns of pre-weaning den visits and nursing behaviour in a captive population of dingoes (Canis dingo). We continuously video-monitored behaviour at dens of four captive, genetically pure, dingo pairs (one litter each) during the first three postpartum weeks just before the start of weaning. Mothers occupied the den almost continuously during the night, but significantly less so during the day, and consistently spent most den time nursing. Fathers were largely absent from inside the den despite lack of apparent aggression from females, low outside temperatures, and space for them inside. They spent a large percentage of time on top of the den, suggestive of sentinel duty, although further experiments are necessary to substantiate this. Although limited to captive animals, our observations are consistent with scant reports of bi-parental care in wild dingoes and with suggestions in the literature that reduced parental care in household and free-ranging domestic dogs might be, at least partly, due to the weakening of bi-parental care during their long history of close association with and dependence on humans. © 2018 Deutsche Gesellschaft für Säugetierkund

Pattern of nipple use by puppies: A comparison of the dingo (Canis dingo) and the domestic dog (Canis familiaris)

Surprisingly little information is available about the behavior of newborn mammals in the functionally vital context of suckling. We have previously reported notable differences in the pattern of nipple use by kittens of the domestic cat and puppies of the domestic dog. Whereas kittens rapidly develop a "teat order," with each individual using principally 1 or 2 particular nipples, puppies show no such pattern. We asked whether the more "chaotic" behavior seen in puppies of the domestic dog (Canis familiaris) could be the result of relaxed selection due to domestication. In a first test of this hypothesis, we studied suckling behavior in 4 litters of wild-type captive dingoes (Canis dingo), a canid species that has inhabited the Australian mainland in substantial numbers for at least 5,000 years with minimal human influence. On all measures of individual puppies' behavior-time spent attached to nipples, lack of individual use of particular nipples and consequent absence of a teat order, lack of synchronized suckling with other littermates, lack of agonistic behavior-we found no differences between the 2 species. In conclusion, we suggest that the difference between the pattern of suckling behavior of kittens of the domestic cat (and other felids) and the domestic dog is not an artifact of domestication, but rather reflects phylogenetic differences between felids and canids as a consequence of their different lifestyles and associated patterns of parental care. These findings emphasize the need for comparative studies to avoid simplistic generalizations from 1 or 2 species across broad taxonomic groups