Les hommes ont oublié cette vérité. Mais tu ne dois pas l'oublier, dit le renard. Tu deviens responsable pour toujours de ce que tu as apprivoisé.
Le Petit Prince, chap. 21

Tuesday 24 February 2015

Cats as predators of endangered bats

Rocha, R. 2015. Look what the cat dragged in: Felis silvestris catus as predators of insular bats and instance of predation on the endangered Pipistrellus enmaderes. Barbastella 8 (1) .

This note reports the predation of a threatened Madeira pipistrelle bat by a domestic house cat. This represents the first confirmed record of cat predation upon a Macaronesian bat and adds to an increasing body of evidence suggesting that free-ranging cats pose a strong negative impact to native insular vertebrate populations.

Monday 23 February 2015

A critical review of habitat use by feral cats

Doherty, T. S., Bengsen, A. J., & Davis, R. A. (2015). A critical review of habitat use by feral cats and key directions for future research and management. Wildlife Research, 41(5), 435-446.

Feral cats (Felis catus) have a wide global distribution and cause significant damage to native fauna. Reducing their impacts requires an understanding of how they use habitat and which parts of the landscape should be the focus of management. We reviewed 27 experimental and observational studies conducted around the world over the last 35 years that aimed to examine habitat use by feral and unowned cats. Our aims were to: (1) summarise the current body of literature on habitat use by feral and unowned cats in the context of applicable ecological theory (i.e. habitat selection, foraging theory); (2) develop testable hypotheses to help fill important knowledge gaps in the current body of knowledge on this topic; and (3) build a conceptual framework that will guide the activities of researchers and managers in reducing feral cat impacts. We found that feral cats exploit a diverse range of habitats including arid deserts, shrublands and grasslands, fragmented agricultural landscapes, urban areas, glacial valleys, equatorial to sub-Antarctic islands and a range of forest and woodland types. Factors invoked to explain habitat use by cats included prey availability, predation/competition, shelter availability and human resource subsidies, but the strength of evidence used to support these assertions was low, with most studies being observational or correlative. We therefore provide a list of key directions that will assist conservation managers and researchers in better understanding and ameliorating the impact of feral cats at a scale appropriate for useful management and research. Future studies will benefit from employing an experimental approach and collecting data on the relative abundance and activity of prey and other predators. This might include landscape-scale experiments where the densities of predators, prey or competitors are manipulated and then the response in cat habitat use is measured. Effective management of feral cat populations could target high-use areas, such as linear features and structurally complex habitat. Since our review shows often-divergent outcomes in the use of the same habitat components and vegetation types worldwide, local knowledge and active monitoring of management actions is essential when deciding on control programs.

Sunday 22 February 2015

Unwanted and unexpected results of low-intensity feral cat culling

Lazenby, B. T., Mooney, N. J., & Dickman, C. R. (2015). Effects of low-level culling of feral cats in open populations: a case study from the forests of southern Tasmania. Wildlife Research, 41(5), 407-420.
Context: Feral cats (Felis catus) threaten biodiversity in many parts of the world, including Australia. Low-level culling is often used to reduce their impact, but in open cat populations the effectiveness of culling is uncertain. This is partly because options for assessing this management action have been restricted to estimating cat activity rather than abundance.

Aims: We measured the response, including relative abundance, of feral cats to a 13-month pulse of low-level culling in two open sites in southern Tasmania.

Methods: To do this we used remote cameras and our analysis included identification of individual feral cats. We compared estimates of relative abundance obtained via capture–mark–recapture and minimum numbers known to be alive, and estimates of activity obtained using probability of detection and general index methods, pre- and post-culling. We also compared trends in cat activity and abundance over the same time period at two further sites where culling was not conducted.

Key results: Contrary to expectation, the relative abundance and activity of feral cats increased in the cull-sites, even though the numbers of cats captured per unit effort during the culling period declined. Increases in minimum numbers of cats known to be alive ranged from 75% to 211% during the culling period, compared with pre- and post-cull estimates, and probably occurred due to influxes of new individuals after dominant resident cats were removed.

Conclusions: Our results showed that low-level ad hoc culling of feral cats can have unwanted and unexpected outcomes, and confirmed the importance of monitoring if such management actions are implemented.

Implications: If culling is used to reduce cat impacts in open populations, it should be as part of a multi-faceted approach and may need to be strategic, systematic and ongoing if it is to be effective.

Influence of hybridization on coyote range expansion

Ellington, E. H., & Murray, D. L. (2015). Influence of hybridization on animal space use: a case study using coyote range expansion. Oikos.

Hybridization between animal species is likely to increase as distributional and reproductive barriers continue to break down due to anthropogenically driven changes in habitat and climate. Yet, the influence of hybridization on ecological interactions and ecosystem function remains understudied. Animal space use, an important component of ecosystem dynamics, is a complex relationship between intrinsic factors, which hybridization can influence, and extrinsic factors, such as environmental heterogeneity. Using the coyote Canis latrans, a well-studied species with a long history of hybridization with wolves and dogs Canis spp., we sought to assess the influence of hybridization relative to environmental factors in determining animal space use. We conducted a meta-regression analysis of 67 datasets on coyote home range size across North America and generated models to predict coyote home range size. Climate (latitude) and environmental variability played important roles in determining patterns of coyote space use, likely through their influence on availability of prey resources. However, we found hybridization to be the preeminent factor driving variation in coyote space use, with non-introgressed populations having considerably smaller home ranges than those from within the Canis hybrid zone of eastern North America. This pattern was upheld despite the variation in environmental factors between areas inside and outside the Canis hybrid zone. Our findings suggest that hybridization may serve as an important factor affecting ecosystems, as hybrids may have altered space requirements, and presumably different niche dimensions, compared to parental species. This, in turn, may influence the role that particular species play within communities.

See more about wild canid hybridisation with dogs

Sunday 15 February 2015

Abandonment of dogs in Latin America: review of literature

ALVES A.J.S.; GUILOUX A.G.A.; ZETUN C.B.; POLO G.; BRAGA G.B.; PANACHÃO L.I.; SANTOS O.; DIAS R.A. 2013 Abandono de cães na América Latina: revisão de literatura /Abandonment of dogs in Latin America: review of literature / Revista de Educação Continuada em Medicina Veterinária e Zootecnia do CRMV-SP / Continuous Education Journal in Veterinary Medicine and Zootechny of CRMV-SP. São Paulo: Conselho Regional de Medicina Veterinária, 11, 2: 34 – 41.

The relinquishment of animals is frequent and common throughout all the Latin America, causing losses in the areas of public health, social, ecological, economic and animal welfare. Among the main causes of pet relinquishment are behavioral problems, lack of space in houses, the lifestyle of the owner, lack of information about the owner responsibilities and costs associated with the keeping of animals. The number of laws related to animal welfare has been growing, due to pressure from the civil population but abandoned animals are a problem of responsibility of all the society. The role of the veterinarian is to inform and educate their customers about the topic. Reduce the relinquishment animal is a public challenge with cultural and long-term solution, and needs the closer look of the whole society.

Friday 13 February 2015

on twitter ...

Thursday 12 February 2015

Are birds winners or loosers in cities?

Shochat, E. 2004. Credit or debit? Resource input changes population dynamics of city-slicker birds. Oikos 106:622-626.

The underlying evolutionary mechanisms of urban bird populations have hardly been studied. High food density and low predation risk serve to explain the global pattern of extremely high urban bird population densities. Both these bottom-up and top-down effects are paradoxical since the per capita amount of food is small due to competition, and domestic predator density is high in cities. The bottom-up paradox can be resolved by taking into account the high food resource-predictability in cities. Concerning the top-down effect, recent studies suggest that at least when it comes to nest predation the effect of cats is minor. I suggest that the combination of high food predictability and low predation risk in cities alter bird foraging behaviour, which in turn affects population dynamics. In terms of density, the result is that bird populations exceed the carrying capacity of the urban environment, costing heavily on body condition and/or life span. Under such conditions the population should consist of a few winners and many losers. Only the winners have sufficient access to food resources and the opportunity to reproduce. The highly predictable continuous input of food in the urban environment allows them to “live on their credit”. They may trade off between offspring body condition and clutch size. In the lack of predation, the losers among the fledglings may survive for a relatively long period, getting just enough energy to survive. Though they may never become healthy enough to reproduce, they will have a major contribution to the observed population density. Results of several case studies seem to support the credit card hypothesis and suggest that it can serve as a general rule for the evolution of animal populations and communities in highly predictable human managed environments.

Wednesday 11 February 2015

Photographic evidence of feral cat predation on Tasmanian fauna

Fancourt, B. (2015). Making a killing: photographic evidence of feral cat (Felis catus) predation of a Tasmanian pademelon (Thylogale billardierii). Australian Mammalogy.

Feral cats (Felis catus) have contributed to the extinction of numerous Australian mammals and are a major threat to many species of conservation significance. Small mammals are considered to be those at greatest risk of cat predation, with risk typically inferred from dietary studies. However, dietary studies may provide only weak inference as to the risk of cat predation for some species. The most compelling evidence of predation risk comes from direct observation of killing events; however such observations are rare and photographic evidence is even rarer. I present photographic evidence of a feral cat killing and consuming an adult female Tasmanian pademelon (Thylogale billardierii). This observation provides direct evidence that feral cats can kill prey up to 4 kg in body mass, with potential implications for the conservation of medium-sized mammals.

Tuesday 10 February 2015

A Feral Cat hunting for a Streaked Shearwater chick

SHIOZAKI,Tatsuya,  Masaki SHIRAI, Masato OSUGI, Maki YAMAMOTO, and Ken YODA. 2014. Predation by Feral Cat on Streaked Shearwater chicks on Awashima. Jpn J Ornithol 63(1) 2014, doi:10.3838/jjo.63.1

Sunday 8 February 2015

Feral cat suppression by apex predator reduces the risk of predation perceived by small prey

Gordon, C. E., Feit, A., Grüber, J., & Letnic, M. (2015). Mesopredator suppression by an apex predator alleviates the risk of predation perceived by small prey. Proceedings of the Royal Society B: Biological Sciences, 282(1802), 20142870.

Predators can impact their prey via consumptive effects that occur through direct killing, and via non-consumptive effects that arise when the behaviour and phenotypes of prey shift in response to the risk of predation. Although predators' consumptive effects can have cascading population-level effects on species at lower trophic levels there is less evidence that predators' non-consumptive effects propagate through ecosystems. Here we provide evidence that suppression of abundance and activity of a mesopredator (the feral cat) by an apex predator (the dingo) has positive effects on both abundance and foraging efficiency of a desert rodent. Then by manipulating predators' access to food patches we further the idea that apex predators provide small prey with refuge from predation by showing that rodents increased their habitat breadth and use of ‘risky′ food patches where an apex predator was common but mesopredators rare. Our study suggests that apex predators' suppressive effects on mesopredators extend to alleviate both mesopredators' consumptive and non-consumptive effects on prey.

Saturday 7 February 2015

Pet food as an attractant for domestic and wild mesocarnivores

Theimer, T. C., Clayton, A. C., Martinez, A., Peterson, D. L., & Bergman, D. L. (2015). Visitation rate and behavior of urban mesocarnivores differs in the presence of two common anthropogenic food sources. Urban Ecosystems, 1-12.

Cat food left out for feral and domestic cats and bird seed spilled from backyard bird feeders are two common anthropogenic food sources that may attract non-target animals like urban mesocarnivores but no studies have quantified mesocarnivore visitation at these food sources. We used motion-activated video cameras to monitor mesocarnivore use of spilled bird seed below 25 bird feeders maintained by residents in four neighborhoods in Flagstaff, Arizona, June-September 2012 and 2014. During the first five nights of monitoring only seed that spilled naturally below feeders was available. On each of the subsequent five nights, we placed a bowl of commercially available dry cat food below feeders so that both spilled seed and cat food were present. In both years, after cat food was added, the number of visits by striped skunks (Mephitis mephitis), raccoons (Procyon lotor) and domestic cats (Felis cattus) doubled and the number of times two animals were present simultaneously also increased. Aggressive interactions, in the form of displays or contacts, increased for all species combinations but significantly only between skunks in the presence of cat food. These results demonstrate that both spilled bird seed and cat food may be exploited frequently by urban mesocarnivores and that the type of food can elicit different behavioral responses that could have important implications for human-wildlife conflict and disease transmission.

Tuesday 3 February 2015

Community knowledge, attitude and practice of rabies in Ethiopia

Serebe, S. G., Tadesse, K. A., Yizengaw, H. A., & Tamrat, S. M. (2014). Study on community knowledge, attitude and practice of rabies in and nearby Gondar town, North West Ethiopia. Journal of Public Health and Epidemiology,6(12), 429-435.

Rabies is one of the disastrous diseases for both animal and human beings. Questionaire based cross-sectional study was conducted in and nearby Gondar town from November 2013 to June 2014. A semi-structured questionnaire was administered to 139 respondents comprised of 96 from urban and 43 from peri-urban areas to assess knowledge, attitude and practice of community about rabies. The current study generally illustrated the presence of significant difference on knowledge and practice of the respondent from urban and peri-urban areas (P < 0.05). Although more than (96%) of the respondents were familiar with the disease, there is mis-perception about the cause and means of transmission of the disease. Starvation and thirst were mentioned by (49.6%) of the respondents as causes of the disease in dogs and 21.6% of them stated any type of contact (irrespective of the skin condition) with saliva of affected individual can transmit the diseases. The result also established that 124 (91.9%) of the respondents were aware that human and other different species of domestic animals can be affected by rabies. However, all respondents (100%) in peri-urban area perceived dog as the only source of infection for human being. Traditional medicine was stated as method of treatment in case of dog bite by 46% of the respondents whereas, 41.7% of respondent used post exposure vaccination. Only 35.8% of the respondent did vaccinate their dogs and level of low vaccination practice was higher in peri-urban area. Raising awareness about dog vaccination and improving access and affordability of the vaccine should be considered in control of the disease.

Feral cat diet in Australia

Doherty, T.S., R. A. Davis, E. J. B. van Etten, D. Algar, N. Collier, C.R. Dickman, G. Edwards, P. Masters, Russell Palmer & S. Robinson. 2015. A continental-scale analysis of feral cat diet in Australia. Journal of Biogeography.

Reducing the impacts of feral cats (Felis catus) is a priority for conservation managers across the globe, and success in achieving this aim requires a detailed understanding of the species’ ecology across a broad spectrum of climatic and environmental conditions. We reviewed the diet of the feral cat across Australia and on Australian territorial islands, seeking to identify biogeographical patterns in dietary composition and diversity, and use the results to consider how feral cats may best be managed.

Australia and its territorial islands.

Using 49 published and unpublished data sets, we modelled trophic diversity and the consumption of eight food groups against latitude, longitude, mean temperature, precipitation, environmental productivity and climate-habitat regions.

We recorded 400 vertebrate species that feral cats feed on or kill in Australia, including 28 IUCN Red List species. We found evidence of continental-scale prey-switching from rabbits to small mammals, previously recorded only at the local scale. The consumption of arthropods, reptiles, rabbits, rodents and medium-sized native mammals varied with different combinations of latitude, longitude, mean annual precipitation, temperature and environmental productivity. The frequency of rodents and dasyurids in cats’ diets increased as rabbit consumption decreased.

Main conclusions
The feral cat is an opportunistic, generalist carnivore that consumes a diverse suite of vertebrate prey across Australia. It uses a facultative feeding strategy, feeding mainly on rabbits when they are available, but switching to other food groups when they are not. Control programmes aimed at culling rabbits could potentially decrease the availability of a preferred food source for cats and then lead to greater predation pressure on native mammals. The interplay between cat diet and prey species diversity at a continental scale is complex, and thus cat management is likely to be necessary and most effective at the local landscape level.

Monday 2 February 2015

Effectiveness of the Birdsbesafe® anti-predation collar

Hall, C. M., Fontaine, J. B., Bryant, K. A., & Calver, M. C. (2015). Assessing the effectiveness of the Birdsbesafe® anti-predation collar cover in reducing predation on wildlife by pet cats in Western Australia. Applied Animal Behaviour Science.

Many pet cats hunt and, irrespective of whether or not this threatens wildlife populations, distressed owners may wish to curtail hunting while allowing their pets to roam. Therefore we evaluated the effectiveness of three patterned designs (simple descriptions being rainbow, red and yellow) of the anti-predation collar cover, the Birdsbesafe® (BBS), in reducing prey captures by 114 pet cats over 2 years in a suburban Australian context. The BBS offers a colourful indicator of a cat's presence and should therefore alert prey with good colour vision (birds and herpetofauna), but not most mammals with limited colour vision. We also interviewed the 82 owners of cats in the study about their experience using the BBS and their assessment of the behavioural responses of their cats.
In the first year of the study, which focused on the effectiveness of different BBS colours, captures of prey with good colour vision were reduced by 54% (95% CL 43% - 64%) when cats were wearing a BBS of any colour, with the rainbow and red BBS more effective than the yellow when birds were prey. Captures of mammals were not reduced significantly. The second year assessed the rainbow BBS alone, and those data combined with rainbow data in the first year found a significant reduction of 47% (95% CL 43% - 57%) in capture of prey with good colour vision, with no effect of differences across years. We found no evidence that cats maintained a lower predation rate once the BBS was removed. Seventy-nine per cent of owners reported that their cats had no problems with the BBS and another 17% reported that their cats adjusted within 2 days. Fourteen owners reported that their cats spent more time at home and ate more while wearing the BBS. Two owners reported their cats stayed away from home more while wearing it. Sixty-four per cent of owners using the red collar, 48% using rainbow and 46% using yellow believed that it worked. Overall, 77% of owners planned to continue using the BBS after the study had finished. The BBS is an option for owners wishing to reduce captures of birds and herpetofauna by free-ranging cats, especially where mammalian prey are introduced pests. To date, the BBS is the only predation deterrent that reduces significantly the number of herpetofauna brought home. It is unsuitable where endangered mammalian prey or large invertebrates are vulnerable to predation by pet cats.

Sunday 1 February 2015

Humane attitude against dog-culling in Romania

Creţan, R. (2015). Mapping protests against dog culling in post‐communist Romania. Area.

This paper explores the spatial expressions and ethical implications of culling dogs. The harsh treatment of street dogs by the Romanian government's hired companies, following the mauling of a child, generated a divide in the opinions of those in authority, animal rights NGOs and the general public. Beyond the case study stands a wider geographical analysis of the media reporting of the protest events on culling dogs and a public opinion survey about the welfare of dogs in Romania. Basing on the theoretical framework of the literature on more-than-human geographies, this contribution presents a critical review of the public response to governmental measures to rapidly implement a street dog law. Different discourses and counter-discourses are considered, from which a framework for improving the ethics of culling dogs could be built.

Cat predation risk contribute to senescence in swallows

BALBONTÍN, J., & MØLLER, A. 2015. Environmental conditions during early life accelerate the rate of senescence in a short-lived passerine bird. Ecology

Environmental conditions experienced in early life may shape subsequent phenotypic traits including life history. We investigated how predation risk caused by domestic cats (Felis silvestris catus) and local breeding density affected patterns of reproductive and survival senescence in Barn Swallows (Hirundo rustica) breeding semicolonially in Denmark. We recorded the abundance of cats and the number of breeding pairs at 39 breeding sites during 24 years and related these to age-specific survival rate and reproductive senescence to test predictions of the life history theory of senescence. We found evidence for actuarial senescence for the first time in this species. Survival rate increased until reaching a plateau in midlife and then decreased later. We also found that survival rate was higher for males than females. Local breeding density or predation risk did not affect survival as predicted by theory. Barn Swallows with short lives did not invest more in reproduction in early life, inconsistent with expectations for trade-offs between reproduction and survival as theory suggests. However, we found that the rate of reproductive decline during senescence was steeper for individuals exposed to intense competition, and predation pressure accelerated the rate of reproductive senescence, but only in sites with many breeding pairs. These latter results are in accordance with one of the predictions suggested by the life history theory of aging. These results emphasize the importance of considering intraspecific competition and interspecific interactions such as predation when analyzing reproductive and actuarial senescence.
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