Living with the enemy: activity rhythms of the red fox and some potential preys in an urban environment

The present study aimed at investigating the activity rhythms of the red fox Vulpes vulpes and three potential preys (i.e. the European hedgehog Erinaceus europaeus, the wood mouse Apodemus sylvaticus, and the Norway rat Rattus norvegicus) in an urban environment. Data were collected as a part of a camera trapping survey, carried out within the municipality of Padua (northeastern Italy). In order to analyse species activity patterns, the R overlap package was used and then the Watson-Wheeler test was run to evaluate whether two overlaps were significantly different. Results show that all the investigated species have nocturnal activities, with “moderate” temporal activity overlap between the red fox and its potential prey. The Watson-Wheeler test showed that the hedgehog was the only potential prey that did not show significant differences in the hours of activity compared to those of the red fox. Instead, statistically significant differences were recorded when the activity rhythm of the red fox was compared with that of the wood mouse or the Norway rat. This may indicate the development of antipredator behaviour or the possibility that the red fox is seeking anthropogenic food sources instead of wild prey or, alternatively, other preferred food items.

Synchronous seasonality in the gut microbiota of wild wood mouse populations

1. The gut microbiome performs many important functions in mammalian hosts, with community composition shaping its functional role. However, what factors drive individual microbiota variation in wild animals and to what extent these are predictable or idiosyncratic across populations remains poorly understood. 2. Here, we use a multi-population dataset from a common rodent species (the wood mouse, Apodemus sylvaticus), to test whether a consistent set of 'core' gut microbes is identifiable in this species, and to what extent the predictors of microbiota variation are consistent across populations. 3. Between 2014 and 2018 we used capture-mark-recapture and 16S rRNA profiling to intensively monitor two wild UK mouse populations and their gut microbiota, as well as characterising the microbiota from a laboratory-housed colony of the same species. 4. Although broadly similar at high taxonomic levels and despite being only 50km apart, the two wild populations did not share a single bacterial amplicon sequence variant (ASV). Meanwhile, the laboratory-housed colony shared many ASVs with one of the wild populations from which it is thought to have been founded decades ago. Despite strong taxonomic divergence in the microbiota, the factors predicting compositional variation in each wild population were remarkably similar. We identified a strong and consistent pattern of seasonal microbiota restructuring that occurred at both sites, in all years, and within individual mice. While the microbiota was highly individualised, seasonal convergence in the gut microbiota among individuals occurred in late winter/early spring. 5. These findings reveal highly repeatable seasonal gut microbiota dynamics across distinct populations of this species, despite divergent taxa being involved. Providing a platform for future work to understand the drivers and functional implications of such predictable seasonal microbiome restructuring, including whether it might provide the host with adaptive seasonal phenotypic plasticity.

Ecological Analysis of the Helminth Community of the Wood Mouse, Apodemus sylvaticus, along an 18-Year Post-Fire Regeneration Period in a Mediterranean Ecosystem

The role of helminths of the wood mouse, Apodemus sylvaticus, as biological indicators of the post-fire regeneration process in Serra Calderona Natural Park, a Mediterranean forest ecosystem located between the provinces of València and Castelló (Valencian Country, Spain), has been analysed for almost twenty years. The helminth ecological analysis of 917 A. sylvaticus (675 originating from the burned area and 242 originating from the control area) has been carried out between the 2nd and 18th post-fire years. The influence of intrinsic (host population density, sex and age) and extrinsic (site, period and year of capture, climate variables) factors on the post-fire evolution of the helminth community of the wood mouse, and the biodiversity, species richness and life cycle of the helminth species was studied. Taking into account the most important results obtained, various aspects of the helminth community dynamics of the wood mouse are confirmed as biological indicators of the post-fire regeneration process in Mediterranean ecosystems. The still existing differences between the two areas are mainly related to the influence of climate variables on the post-fire regeneration process. Moreover, the important role that helminth parasites of the wood mouse play as biological indicators of this process in Mediterranean ecosystems is demonstrated.

Unexpected involvement of a second rodent species makes impacts of introduced rats more difficult to detect

Rodent predators are implicated in declines of seabird populations, and removing introduced rats, often, but not always, results in the expected conservation gains. Here we investigated the relationship between small mammal (Norway rat, wood mouse and pygmy shrew) abundance and Manx shearwater breeding success on the island of Rum, Scotland, and tested whether localised rodenticide treatments (to control introduced Norway rats) increased Manx shearwater breeding success. We found that Manx shearwater breeding success was negatively correlated with late summer indices of abundance for rats and mice, but not shrews. On its own, rat activity was a poor predictor of Manx shearwater breeding success. Rat activity increased during the shearwater breeding season in untreated areas but was supressed in areas treated with rodenticides. Levels of mouse (and shrew) activity increased in areas treated with rodenticides (likely in response to lower levels of rat activity) and Manx shearwater breeding success was unchanged in treated areas (p < 0.1). The results suggest that, unexpectedly, negative effects from wood mice can substitute those of Norway rats and that both species contributed to negative impacts on Manx shearwaters. Impacts were intermittent however, and further research is needed to characterise rodent population trends and assess the long-term risks to this seabird colony. The results have implications for conservation practitioners planning rat control programmes on islands where multiple rodent species are present.

DNA metabarcoding dietary analyses of the wood mouse Apodemus speciosus on Innoshima Island, Japan, and implications for primer choice

We used DNA metabarcoding to assess the seasonal diets of the large Japanese wood mouse, Apodemus speciosus (Muridae, Rodentia), in forest edges adjacent to citrus orchards on Innoshima Island, Japan. We used one chloroplast and three mitochondrial DNA barcoding markers to determine mouse diets. Among the various plant and invertebrate diets, A. speciosus typically consumed Chinese cork oak (Quercus variabilis) in early spring (likely acorns preserved during winter) and gypsy moths (Lymantria dispar, a forest pest) in late spring and summer. In addition, we found that A. speciosus also preyed on orchard pests, including the gutta stink bug and other potentially harmful invertebrates. The season during which A. speciosus preyed on stink bugs corresponded with the harvest of orchard products. This study revealed several of the ecological roles of A. speciosus within the boundary zone between forest and human ecosystems. Furthermore, based on the performance of various mitochondrial markers in dietary profiling of invertebrate food items, we recommend the multi-locus DNA metabarcoding method to comprehensively assess the diet of A. speciosus.

Winter diet of Long-eared Owls (Asio otus) in the southern Pannonian Plain (Serbia, Vojvodina)

Owl diets undergo qualitative changes across the different regions of their area of distribution. During the four winters (from 2014–15 to 2017–18), Long-eared Owls’ pellets were collected at three winterroosts located at the southern part of Pannonian Plain, in the Serbian province of Vojvodina. In 8070 prey items from pellets, we identified 16 mammal and 32 bird species. The Common Vole was the dominant prey species with a proportion in a range from 27.4% to 71.6%. The Muridae family formed a supplementary part of the diet: Mus sp., wood mouse and harvest mouse, during all winters. Birds were also a major supplementary prey during winter 2014–15, comprising 10.6%. A comparison of our results with the diet of Long-eared Owls wintering at the northern Pannonian plain (southwestern Slovakia) indicated an increase the proportion of some species in the southern part. How different land uses in agriculture and environmental conditions may be reflected in the food supply are discussed in relation to the diet composition of Long-eared Owls and an environment whose is richer provides both growing diversity in the diet of these owls and an expansion of their food niche. Our study described the Long-eared Owl as opportunistic predators expanding their food niche in the presence of diversified prey.

Lunar illumination shapes small mammal activity in lowland agricultural landscapes

The behavioural patterns of small mammalian prey species have been shown to be widely impacted by predator avoidance. Cues to avoid predation may come from the predator itself or environmental cues, such as moonlight and available vegetative cover. We investigated how the activity of the bank vole Myodes glareolus, field vole Microtus agrestis, wood mouse Apodemus sylvaticus and the common shrew Sorex araneus were impacted by changes in habitat and lunar light conditions across a range of habitats (mainly grassland protected sites) in Lincolnshire (UK). Microhabitat vegetation density as well as weather conditions were recorded across all trap sites, with Longworth traps set overnight and the successfully captured species recorded the following morning. Overnight temperature was found to positively influence capture rate across all species. The lunar phase was found to significantly impact capture rate, with the gibbous lunar phase providing the highest capture rate across species. The interaction between illumination and vegetation density was also found to impact activity levels in the bank vole and wood mouse, with the bank vole showing higher activity in thick vegetation at low light levels and across habitats at higher light levels, whereas wood mice were more often captured in intermediate cover at low and intermediate illumination but across a range of habitats at brighter illumination. In combination, it suggests that small mammal activity is altered to potentially reduce predation risk. However, in this community at least, brighter lunar illumination leads to increase activity.

The occurrence of Sumatran tiger (Panthera tigris sumatrae) in an industrial plantation forest area, North Sumatra, Indonesia

Sumatran tiger lives in the remaining forests on the Sumatra island, both in conservation and production areas. There are not many tiger monitoring activities conducted in production forest. Using camera traps this occupancy survey of Sumatran tiger (Panthera tigris sumatrae) carried out in a plantation forest area of PT. Toba Pulp Lestari (PT. TPL) to obtain information and monitor tiger presence in the area. However, there were no Sumatran tigers captured by the camera traps during the occupancy activities. The existence of Sumatran tiger was proven by the finding of footprints and scrapes. Other species were photographed by the camera traps, such as marbled cat ((Pardofelis marmorata), pig-tailed monkey (Macaca nemestrina), treeshrew (Tupaia sp.), Asian palm civet (Paradoxurus hermaphroditus), lizards (Eutropis sp.), Hoogerwerf’s pheasant (Lophura hoogerwerfi), wood mouse (Apodemus sylvaticus) as well as birds. It is assumed that the Sumatran tiger didn’t cross the location of research during the camera installation period. However, there are several other reasons why Sumatran tigers weren’t captured by camera traps, such as the camera traps observation time was too short and didn’t cover a larger area, so it lessens the opportunity of encounter with Sumatran tiger.Harimau Sumatera hidup di hutan yang masih tersisa di pulau Sumatera, baik di kawasan hutan konservasi maupun hutan produksi. Kegiatan pemantauan harimau di hutan produksi belum banyak dilakukan. Dengan menggunakan camera trap, survei okupansi harimau sumatera (Panthera tigris sumatrae) ini dilakukan di areal konsesi hutan tanaman industri PT. Toba Pulp Lestari (PT. TPL) untuk mendapatkan informasi dan memantau keberadaan harimau di kawasan tersebut. Namun, tidak ada harimau sumatera yang terfoto oleh kamera trap selama kegiatan survei okupansi. Keberadaan harimau sumatera dibuktikan dengan ditemukannya jejak tapak dan cakaran. Selain itu, terdapat ppesies lain yang terfoto oleh kamera trap, seperti kucing batu ((Pardofelis marmorata), beruk (Macaca nemestrina), tupai tanah (Tupaia sp.), musang pandan (Paradoxurus hermaphroditus), kadal (Eutropis sp.), sempidan aceh (Lophura hoogerwerfi), tikus hutan (Apodemus sylvaticus) serta burung. Diasumsikan bahwa harimau sumatera tidak melintasi lokasi penelitian selama masa pemasangan kamera. Namun, terdapat beberapa alasan lain mengapa harimau sumatera tidak terfoto kamera trap, seperti waktu pengamatan kamera trap yang terlalu singkat dan tidak mencakup area yang lebih luas, sehingga memperkecil peluang perjumpaan dengan harimau sumatera.