Cat-wildlife interactions and zoonotic disease risk: a call for more and better community science data

Due to their close interaction with both wildlife and humans, free-ranging domestic animals are well-suited to act as conveyors of zoonotic pathogens. Yet, although cats Felis catus are major predators of bats and other groups of zoonotic concern (e.g., rodents and birds), mounting evidence suggests that their role in the emergence of zoonotic diseases may be unappreciated. Here, we use bat–cat information extracted from the popular iNaturalist platform as a case in point to illustrate the potential of community science and social media to expand our understanding of pet-wildlife interactions. Although observations of cats preying on bats were more prevalent in Europe and North America, evidence of such interactions was documented across different geographic regions, revealing a relatively high incidence of bat predation by cats and providing evidence of cat–bat interactions previously unreported in the scientific literature. The lack of surveillance focused on cats and other pets as bridging hosts for zoonotic spillover events is concerning, considering the recognised risks they pose. Community science is a relatively untapped source of information for pet-wildlife interactions of zoonotic relevance. It is crucial that we gain a better understanding of the interaction between free-ranging pets and wildlife to better understand their potential contribution to past and future disease outbreaks. Failing to do so not only jeopardises human health but also puts pets at risk

Sensibilité des populations de roussettes ( Mégachiroptères, Pteropodidae) aux prélèvements cynégétiques et aux prédateurs introduits : une approche éco-démographique en Nouvelle Calédonie

The destruction and degradation of natural habitats, invasive species and overexploitation are the three main threats to biodiversity to date. There is an urgent need to accurately assess the threats to declining and even threatened species, particularly those that are exploited, and to develop evidence-based management solutions.. Here we present a study on tbe population status oftwo sympatric flying fox species, Pteropus ornatus (endemie) and P. tonganus (native), and the impact of hunting and predation by the ferai catFelis catus in New Caledonia. The study offlying fox roost occupancy in the North Province shows a 33% disapearance in 40 years. The flying fox population on Grande Terre is estimated at about 735,000 individuals (ofboth species) and the annual hunting rate at 7%. Integrated stochastic modelling of this population suggests tbat current harvesting levels could lead to a decline of up to 80% in the next 30 years. Temporary hunting ban and/or protected areas appear, in addition to being combinable, to be the most acceptable and effective management options for hunters. An analysis of tbe data available worldwide shows that ali forms of cats prey on bats in all habitats and tbat this tbreat is probably largely underestimated. Finally, initial results suggest tbat flying fox predation by ferai cats in New Caledonia is ofthe same order of magnitude as hunting. This study proposes a framework for assessing the sustainability of hunting game species in an integrated adaptive management approach, taking into account other threat factors such as invasive species

Sensitivity of flying fox (Megachiroptera, Pteropodidae) populations to hunting and introduced predators : an eco-demographie approach in New Caledonia.

La dégradation des habitats naturels, les espèces exotiques envahissantes et la surexploitation sont les trois principales menaces pesant sur la biodiversité à ce jour. Nous présentons ici des travaux sur 1'état des populations de deux espèces de roussettes sympatriques, Pteropus ornatus (endémique) et P. tonganus (native) et l'impact de la chasse et de la prédation par le chat haret Felis catus, en Nouvelle-Calédonie. L'étude de l'occupation des gîtes de roussettes en province Nord met en évidence une disparition de 33% en 40 ans. La population de roussettes sur la Grande Terre est estimée à environ 735 000 individus (des deux espèces confondues) et le taux de prélèvement de chasse annuel à 7%. La modélisation stochastique intégrée de cette population suggère que les prélèvements actuels pourraient conduire à un déclin de près de 80% dans les 30 prochaines années. Les mises en place de moratoires temporaires et/ou de zones protégées apparaissent, en plus d'être combinables, comme les options de gestion les plus acceptables pour les chasseurs mais aussi la plus efficaces. Une analyse des données disponibles au niveau mondial montre que toutes les formes de chats s'attaquent aux chauves-souris dans l'ensemble des habitats et que cette menace est sans doute largement sous-estimée. Enfin, des premiers résultats suggèrent un taux prédation des roussettes par les chats harets en Nouvelle-Calédonie de même ordre de grandeur que celui de la chasse. Cette étude propose un cadre d'évaluation de la soutenabilité à la chasse d'espèces gibier dans une démarche de gestion adaptative intégrée en prenant en compte d'autres facteurs de menace tels que les espèces invasives.Habitat degradation, invasive species and overexploitation are currently tbe three main threats to biodiversity. Here we present a study on tbe population status oftwo sympatric flying fox species, Pteropus ornatus (endemie) and P. tonganus (native), and the impact of hunting and predation by the ferai catFelis catus in New Caledonia. The study offlying fox roost occupancy in the North Province shows a 33% disapearance in 40 years. The flying fox population on Grande Terre is estimated at about 735,000 individuals (ofboth species) and the annual hunting rate at 7%. Integrated stochastic modelling of this population suggests tbat current harvesting levels could lead to a decline of up to 80% in the next 30 years. Temporary hunting ban and/or protected areas appear, in addition to being combinable, to be the most acceptable and effective management options for hunters. An analysis of tbe data available worldwide shows that ali forms of cats prey on bats in all habitats and tbat this tbreat is probably largely underestimated. Finally, initial results suggest tbat flying fox predation by ferai cats in New Caledonia is ofthe same order of magnitude as hunting. This study proposes a framework for assessing the sustainability of hunting game species in an integrated adaptive management approach, taking into account other threat factors such as invasive species

Make flying-fox hunting sustainable again: Comparing expected demographic effectiveness and hunters’ acceptance of more restrictive regulations

International audienc

Exploring the potential for online data sources to enhance species threat mapping through the case study of global bat exploitation

Expanding digital data sources, including social media and online news, provide a low-cost way to examine human-nature interactions, such as wildlife exploitation. However, the extent to which using such data sources can expand or bias understanding of the distribution and intensity of threats has not been comprehensively assessed. To address this gap, we quantified the geographical and temporal distribution of online sources documenting the hunting and trapping, consumption, or trade of bats (Chiroptera) and compared these with the distribution of studies obtained from a systematic literature search and species listed as threatened by exploitation on the International Union for Conservation of Nature Red List. Online records were collected using automated searches of Facebook, Twitter, Google, and Bing and were filtered using machine classification. This yielded 953 relevant social media posts and web pages, encompassing 1099 unique records of bat exploitation from 84 countries. Although the number of records per country was significantly predicted by the number of academic studies per country, online records provided additional locations and more recent records of bat exploitation, including 22 countries not present in academic literature. This demonstrates the value of online resources in providing more complete geographical representation. However, confounding variables can bias the analysis of spatiotemporal trends. Online bat exploitation records showed peaks in 2020 and 2014, after accounting for increases in internet users through time. The second of these peaks could be attributed to the COVID-19 outbreak, and speculation about the role of bats in its epidemiology, rather than to true changes in exploitation. Overall, our results showed that data from online sources provide additional knowledge on the global extent of wildlife exploitation, which could be used to identify early warnings of emerging threats and pinpoint locations for further research.</p

Rapid recolonisation of feral cats following intensive culling in a semi-isolated context

International audienceInvasive feral cats threaten biodiversity at a global scale. Mitigating feral cat impacts and reducing their populations has therefore become a global conservation priority, especially on islands housing high endemic biodiversity. The New Caledonian archipelago is a biodiversity hotspot showing outstanding terrestrial species richness and endemism. Feral cats prey upon at least 44 of its native vertebrate species, 20 of which are IUCN Red-listed threatened species. To test the feasibility and efficiency of culling, intensive culling was conducted in a peninsula of New Caledonia (25.6 km²) identified as a priority site for feral cat management. Live-trapping over 38 days on a 10.6 km² area extirpated 36 adult cats, an estimated 44% of the population. However, three months after culling, all indicators derived from camera-trapping (e.g.,abundance, minimum number of individuals and densities) suggest a return to pre-culling levels. Com- pensatory immigration appears to explain this unexpectedly rapid population recovery in a semi-isolated context. Since culling success does not guarantee a long-term effect, complementary methods like fenc- ing and innovative automated traps need to be used, in accordance with predation thresholds identified through modelling, to preserve island biodiversity. Testing general assumptions on cat management, this article contributes important insights into a challenging conservation issue for islands and biodiversity hotspots worldwide

Flying Fox Hemolytic Fever, Description of a New Zoonosis Caused by Candidatus Mycoplasma haemohominis

International audienceBackground : Hemotropic mycoplasmas, previously classified in the genus Eperythrozoon, have been reported as causing human infections in Brazil, China, Japan, and Spain.Methods : In 2017, we detected DNA from Candidatus Mycoplasma haemohominis in the blood of a Melanesian patient from New Caledonia presenting with febrile splenomegaly, weight loss, life-threatening autoimmune hemolytic anemia, and hemophagocytosis. The full genome of the bacterium was sequenced from a blood isolate. Subsequently, we retrospectively (2011–2017) and prospectively (2018–2019) tested patients who had been hospitalized with a similar clinico-biological picture. In addition, as these patients had been in contact with frugivorous bats (authorized under conditions for hunting and eating in New Caledonia), we investigated the role of these animals and their biting flies by testing them for hemotropic mycoplasmas.Results : There were 15 patients found to be infected by this hemotropic mycoplasma. Among them, 4 (27%) died following splenectomy performed either for spontaneous spleen rupture or to cure refractory autoimmune hemolytic anemia. The bacterium was cultivated from the patient’s blood. The full genome of the Neocaledonian Candidatus M. haemohominis strain differed from that of a recently identified Japanese strain. Of 40 tested Pteropus bats, 40% were positive; 100% of collected bat flies Cyclopodia horsfieldi (Nycteribiidae, Diptera) were positive. Human, bat, and dipteran strains were highly similar.Conclusions : The bacterium being widely distributed in bats, Candidatus M. haemohominis, should be regarded as a potential cause of severe infections in humans

Monitoring hunted species of cultural significance: Estimates of trends, population sizes and harvesting rates of flying-fox (Pteropus sp.) in New Caledonia

International audienceAssessing population trends and their underlying factors is critical to propose efficient conservation actions. This assessment can be particularly challenging when dealing with highly mobile, shy and nocturnal animals such as flying-foxes. Here we investigated the dynamics of hunted populations of Pteropus ornatus and P. tonganus in the Northern Province of New Caledonia. First, an ethno-ecological survey involving 219 local experts identified 494 flying-fox roosts. Current status was assessed for 379 of them, among which 125 were no longer occupied, representing a loss of 33% over ca. 40 years. Second, species-specific counts conducted at 35 roosts, and a sample of animals killed by hunters, revealed that the endemic species, P. ornatus, was dominant (68.5%). Between 2010 and 2016, 30 roosts were counted annually during the pre-parturition period. Roosts size averaged 1,425 ± 2,151 individuals (N = 180 counts) and showed high among-year variations (roost-specific CV = 37-162%). If we recorded significant inter-annual variation, we did not detect a significant decline over the 7-yr period, although one roost went possibly extinct. Population size of the two species combined was estimated at 338,000−859,000 individuals distributed over ca. 400 roosts in the Northern Province. Flying-foxes are popular game species and constitute traditional food for all communities of New Caledonia. Annual bags derived from a food survey allowed us to estimate harvesting rates at 5-14%. Such a level of harvesting for species with a 'slow' demography, the occurrence of poaching and illegal trade, suggest the current species use might not be sustainable and further investigations are critically needed. PLOS ONE | https://doi.org/10.1371/journal.pone