Rethinking Habitat Occupancy Modeling and the Role of Diel Activity in an Anthropogenic World

Current methods to model species habitat use through space and diel time are limited. Development of such models is critical when considering rapidly changing habitats where species are forced to adapt to anthropogenic change, often by shifting their diel activity across space. We use an occupancy modeling framework to specify the multistate diel occupancy model (MSDOM), which can evaluate species diel activity against continuous response variables that may impact diel activity within and across seasons or years. We used two case studies, fosas in Madagascar and coyotes in Chicago, Illinois, to conceptualize the application of this model and to quantify the impacts of human activity on species spatial use in diel time. We found support that both species varied their habitat use by diel states—in and across years and by human disturbance. Our results exemplify the importance of understanding animal diel activity patterns and how human disturbance can lead to temporal habitat loss. The MSDOM will allow more focused attention in ecology and evolution studies on the importance of the short temporal scale of diel time in animal-habitat relationships and lead to improved habitat conservation and management

Exploring and interpreting spatiotemporal interactions between native and invasive carnivores across a gradient of rainforest degradation

Studies of elusive carnivores often rely on passive sampling when investigating either spatial or temporal interactions. However, inference on behavioral mechanisms are usually lacking. We present an analysis that combines previously published spatial co-occurrence estimates and temporal kernel density estimates to explore spatiotemporal interspecific interactions. We do so by deriving a spatiotemporal value (STV) that is a relative measure of potential interaction in both niche dimensions, across a gradient of degradation, for rainforest carnivore pairs in Madagascar. We also use a conceptual framework to provide insight into the potential behavioral mechanisms of habitat selection. Of the six native and three invasive carnivores, we estimate the spatiotemporal interactions for twelve pairings, which range from no spatial/temporal relationship (n = 5) to spatiotemporal aggregation or segregation (n = 7). We visualized these spatiotemporal interactions along a fragmentation gradient and demonstrate that these interactions are not static, as STV overlap increases with increasing anthropogenic disturbance. Of the three invasive carnivores (free-ranging dogs Canis familiaris, cats Felis species, and small Indian civets Viverricula indica) the latter had the highest number of spatial occurrence (n = 4) and spatiotemporal overlap (n = 4) relationships with native carnivores. Our results highlight the potential for increasing direct and indirect interactions between native and invasive species as forest degradation and invasive predators increase. Our approach allows us to better understand adaptive behaviors, plasticity in temporal activity, community assemblage, and to develop targeted conservation strategies to manage ecological communities in rapidly changing ecosystems

Preliminary survey of the threatened carnivores in the Daraina Loky-Manambato Protected Area, Madagascar

Madagascar’s protected areas safeguard numerous threatened endemic plant and animal species, including Euplerid carnivores, considered to be the most threatened yet understudied group of carnivores globally. The Loky-Manambato Protected Area (PA) in northern Madagascar encompasses a unique transitional forest ecosystem that is under pressure from forest loss and fragmentation. We provide the first photographic survey of Madagascar’s carnivore community occupying this region with the aim of documenting carnivore species richness, relative activity (Trap Success), and spatial distribution (Naïve occupancy) across the landscape. To do this, we used 60 motion-activated cameras to survey along established trails in three forest patches across the Loky-Manambato PA: Antsahabe, Bekaraoka, and Antsaharaingy. We surveyed each forest for two weeks in September and October 2018. We collected 498 independent captures of fauna across the landscape, including five of the six endemic carnivores known to occupy eastern Madagascar: Galidia elegans, Galidictis fasciata, Eupleres goudotii, Fossa fossana, and Cryptoprocta ferox. We found F. fossana and G. elegans to be the most active and widely distributed carnivores, while C. ferox, G. fasciata and E. goudotii were the least. Additionally, we documented the presence of two invasive carnivores: Canis familiaris and Felis catus. These findings extended the northern-most known range of Galidictis fasciata (Antsahabe) and Fossa fossana (Bekaraoka) into the Loky-Manambato PA. Forest size was not a good predictor of activity or occurrence as the largest forest patch in Bekaraoka had the fewest captures of all carnivores. Our findings highlight some of the biodiversity within the Loky-Manambato PA and the need for effective management across this unique transitional forest ecosystem.  RÉSUMÉLes aires protégées de Madagascar protègent de nombreuses espèces végétales et animales endémiques menacées, y compris les carnivores eupléridés. Les carnivores eupléridés sont considérés comme l'un des groupes de carnivores les plus menacés mais les moins étudiés au monde. L'aire protégée (PA) de Loky- Manambato dans le nord de Madagascar englobe un écosystème forestier de transition unique qui subit la pression de la perte et de la fragmentation des forêts. Nous fournissons la première étude photographique de la communauté de carnivores de Madagascar occupant cette région dans le but de documenter la richesse en espèces de carnivores, l'activité relative (Trap Success) et la distribution spatiale (Naïve occupancy) à travers le paysage. Pour ce faire, nous avons utilisé 60 caméras activées par le mouvement pour surveiller le long des sentiers établis dans trois parcelles forestières à travers l’AP Loky-Manambato : Antsahabe, Bekaraoka et Antsaharaingy. Nous avons étudié chaque forêt pendant deux semaines en septembre et octobre 2018. Nous avons procédé à 498 captures indépendantes de la faune à travers le paysage, incluant cinq des six carnivores endémiques connus pour habiter l'Est de Madagascar : Galidia elegans, Galidictis fasciata, Eupleres goudotii, Fossa fossana et Cryptoprocta ferox. Nous avons constaté que F. fossana et G. elegans étaient les carnivores les plus actifs et les plus largement distribués, tandis que C. ferox, G. fasciata et E. goudotii étaient les moins nombreux. De plus, nous avons documenté la présence de deux carnivores envahissants : Canis familiaris et Felis catus. Ces découvertes ont étendu l'aire de répartition la plus septentrionale connue de Galidictis fasciata (Antsahabe) et de Fossa fossana (Bekaraoka) dans l’AP Loky-Manambato. La taille de la forêt n'était pas un bon prédicteur de l'activité ou de l'occurrence car la plus grande parcelle forestière de Bekaraoka avait la moindre présence de tous les carnivores. Nos résultats mettent en évidence une partie de la biodiversité au sein de Loky-Manambato PA et la nécessité d'une gestion efficace dans cet écosystème forestier de transition uniqu

Causative Agent of Canine Heartworm (Dirofilaria immitis) Detected in Wild Lemurs

The lemurs of Madagascar are threatened by human activities. We present the first molecular detection of canine heartworm (Dirofilaria immitis) in a wild non-human primate, the mouse lemur (Microcebus rufus). Zoonotic D. immitis infection has been associated with clinical pathology that includes serious and often fatal cardiac and pulmonary reactions. With human encroachment and associated increases in free-roaming dog populations in Madagascar, we examined lemurs for zoonotic canid pathogens. D. immitis presents a new potential conservation threat to lemurs. We highlight the need for wide-ranging and effective interventions, particularly near protected areas, to address this growing conservation issue

Assessment of the Threatened Carnivore Community in the Recently Expanded Rainforest protected Area Anjanaharibe-Sud Special Reserve, Madagascar

Madagascar is an island nation renowned for its biodiversity and species endemism, yet it is still largely understudied despite intense anthropogenic threats including forest loss and edge effects. Anjanaharibe-Sud Special Reserve is a recently expanded rainforest protected area that is lacking detailed surveys and assessments of the native carnivore community of the endemic family Eupleridae. To identify which terrestrial carnivores occupy the reserve and what anthro- pogenic disturbances and factors best explain their occurrence patterns, we deployed 35 motion- activated cameras to detect native and introduced carnivores. From November 2018 to February 2019, we collected 2918 unique capture events (all species) and confirmed the presence of 5 eup- lerids: Galidia elegans, Galidictis fasciata, Eupleres goudotii, Fossa fossana, and Cryptoprocta ferox. These results extend the known range of E. goudotii and G. fasciata. In the reserve, F. fossana and G. elegans were the most common and widespread native carnivores, while E. goudotii was the rarest. We highlight the negative impact of edge effects on G. fasciata and F. fossana and the threat posed by the free-ranging non-native carnivore C. familiaris. This study represents the first detailed survey and occurrence estimates of the carnivore community of this protected area, allow- ing comparison with other protected areas in Madagascar. Our empirical findings show that anthro- pogenic disturbance negatively impacts carnivore existence within the Anjanaharibe-Sud Special Reserve and provide important management recommendations for protecting the carnivore com- munity and the co-occurring wildlife living within this area

Data from: Hunting, exotic carnivores, and habitat loss: anthropogenic effects on a native carnivore community, Madagascar

The wide-ranging, cumulative, negative effects of anthropogenic disturbance, including habitat degradation, exotic species, and hunting, on native wildlife has been well documented across a range of habitats worldwide with carnivores potentially being the most vulnerable due to their more extinction prone characteristics. Investigating the effects of anthropogenic pressures on sympatric carnivores is needed to improve our ability to develop targeted, effective management plans for carnivore conservation worldwide. Utilizing photographic, line-transect, and habitat sampling, as well as landscape analyses and village-based bushmeat hunting surveys, we provide the first investigation of how multiple forms of habitat degradation (fragmentation, exotic carnivores, human encroachment, and hunting) affect carnivore occupancy across Madagascar’s largest protected area: the Masoala-Makira landscape. We found that as degradation increased, native carnivore occupancy and encounter rates decreased while exotic carnivore occupancy and encounter rates increased. Feral cats (Felis species) and domestic dogs (Canis familiaris) had higher occupancy than half of the native carnivore species across Madagascar’s largest protected landscape. Bird and small mammal encounter rates were negatively associated with exotic carnivore occupancy, but positively associated with the occupancy of four native carnivore species. Spotted fanaloka (Fossa fossana) occupancy was constrained by the presence of exotic feral cats and exotic small Indian civet (Viverricula indica). Hunting was intense across the four study sites where hunting was studied, with the highest rates for the small Indian civet ( individuals consumed/year), the ring-tailed vontsira (Galidia elegans) ( consumed/year), and the fosa (Cryptoprocta ferox) ( consumed/year). Our modeling results suggest hunters target intact forest where carnivore occupancy, abundance, and species richness, are highest. These various anthropogenic pressures and their effects on carnivore populations, especially increases in exotic carnivores and hunting, have wide-ranging, global implications and demand effective management plans to target the influx of exotic carnivores and unsustainable hunting that is affecting carnivore populations across Madagascar and worldwide

Hunting, Exotic Carnivores, and Habitat Loss: Anthropogenic Effects on a Native Carnivore Community, Madagascar

<div><p>The wide-ranging, cumulative, negative effects of anthropogenic disturbance, including habitat degradation, exotic species, and hunting, on native wildlife has been well documented across a range of habitats worldwide with carnivores potentially being the most vulnerable due to their more extinction prone characteristics. Investigating the effects of anthropogenic pressures on sympatric carnivores is needed to improve our ability to develop targeted, effective management plans for carnivore conservation worldwide. Utilizing photographic, line-transect, and habitat sampling, as well as landscape analyses and village-based bushmeat hunting surveys, we provide the first investigation of how multiple forms of habitat degradation (fragmentation, exotic carnivores, human encroachment, and hunting) affect carnivore occupancy across Madagascar’s largest protected area: the Masoala-Makira landscape. We found that as degradation increased, native carnivore occupancy and encounter rates decreased while exotic carnivore occupancy and encounter rates increased. Feral cats (<i>Felis species</i>) and domestic dogs (<i>Canis familiaris</i>) had higher occupancy than half of the native carnivore species across Madagascar’s largest protected landscape. Bird and small mammal encounter rates were negatively associated with exotic carnivore occupancy, but positively associated with the occupancy of four native carnivore species. Spotted fanaloka (<i>Fossa fossana</i>) occupancy was constrained by the presence of exotic feral cats and exotic small Indian civet (<i>Viverricula indica</i>). Hunting was intense across the four study sites where hunting was studied, with the highest rates for the small Indian civet (<math><mrow>x<mo>¯</mo> = <mn>90</mn></mrow></math> individuals consumed/year), the ring-tailed vontsira (<i>Galidia elegans</i>) (<math><mrow>x<mo>¯</mo> = <mn>58</mn></mrow></math> consumed/year), and the fosa (<i>Cryptoprocta ferox</i>) (<math><mrow>x<mo>¯</mo> = <mn>31</mn></mrow></math> consumed/year). Our modeling results suggest hunters target intact forest where carnivore occupancy, abundance, and species richness, are highest. These various anthropogenic pressures and their effects on carnivore populations, especially increases in exotic carnivores and hunting, have wide-ranging, global implications and demand effective management plans to target the influx of exotic carnivores and unsustainable hunting that is affecting carnivore populations across Madagascar and worldwide.</p></div