Distribution Of Small Mammals Research Articles

A multi-taxa approach reveals contrasting responses of arthropod communities and related ecosystem services to field margin proximity and crop type

Agricultural intensification and landscape simplification are among the major drivers of biodiversity loss in agricultural landscapes. Increasing field edges might be a key solution for enhancing biodiversity and related ecosystem services within arable fields. In this study, we investigated the spatial distribution of nine arthropod groups and weed seed and pest predation rates across different distances from field edges and crop types. Furthermore, we tested the relationship between local carabid abundance and species richness and directly measured weed seed and pest predation rates. Most of the investigated taxa were not affected by field margin proximity, except for carabid species richness and the abundance of bees and wasps, hoverflies, and myriapods, which were high near the edge. We found a higher abundance of carabids and herbivores in oilseed rape compared to other crops, while hoverflies, bees and wasps were more abundant in cereal. True bug abundance was significantly higher in oilseed rape interiors compared to edges. Weed seed predation and pest predation by small mammals were the highest at 36 m from the field margin, probably due to small mammal distribution, while pest predation by arthropods did not show any significant pattern. Both weed seed predation rate and arthropod pest predation were positively related to carabid abundance and negatively to species richness. Contrasting responses across nine investigated arthropod taxa indicate that re-designing agricultural landscapes to support biodiversity across taxa will be challenging, and further studies are needed to fully understand the spatial distribution of arthropods and related ecosystem services in agricultural landscapes.

Shrew Communities in Mediterranean Agro-Ecosystems of Central Greece: Associations with Crop Types, Land Uses, and Soil Parameters.

Shrew communities play a crucial role in a diverse range of natural, urban, and agricultural ecosystems. We used Barn owl diet analysis as the ideal proxy to assess small-mammal distribution patterns on large spatial scales. More than 10,000 pellets were analyzed from Thessaly, the largest agricultural prefecture located in central Greece. A total of more than 29,000 prey items were identified, one of the largest datasets used in similar analyses in Europe. Three discrete shrew species were present in Thessaly agricultural plains, central Greece (Güldenstädt's shrew Crocidura gueldenstaedtii, Bi-coloured shrew Crocidura leucodon, and Pygmy white-toothed shrew Suncus etruscus), which comprised a total of 7452 shrews, representing 25.64% of the total small-mammals' dataset. C. gueldenstaedtii and S. etruscus demonstrated strong associations with heavy argillaceous-clay soils and Vertisol soil types, whereas S. etruscus was also associated with non-irrigated land and non-intensive cultivated plots. C. leucodon demonstrated no significant associations to any environmental gradient and demonstrated habitat plasticity, most possibly shaped by existing resources and competition. Our study highlights the important insights gained from Barn owl diet analysis in respect of small-mammal assemblages on broad geographical scales, and the inclusion of soil parameters as drivers of habitat suitability and distribution patterns for small-mammal responses.

Sharing space between native and invasive small mammals: Study of commensal communities in Senegal.

Urbanization processes are taking place at a very high rate, especially in Africa. At the same time, a number of small mammal species, be they native or invasive, take advantage of human-induced habitat modifications. They represent commensal communities of organisms that cause a number of inconveniences to humans, including potential reservoirs of zoonotic diseases. We studied via live trapping and habitat characterization such commensal small mammal communities in small villages to large cities of Senegal, to try to understand how the species share this particular space. Seven major species were recorded, with exotic invasive house mice (Mus musculus) and black rats (Rattus rattus) dominating in numbers. The shrew Crocidura olivieri appeared as the main and more widespread native species, while native rodent species (Mastomys natalensis, M. erythroleucus, Arvicanthis niloticus and Praomys daltoni) were less abundant and/or more localized. Habitat preferences, compared between species in terms of room types and characteristics, showed differences among house mice, black rats and M. natalensis especially. Niche (habitat component) breadth and overlap were measured. Among invasive species, the house mouse showed a larger niche breadth than the black rat, and overall, all species displayed high overlap values. Co-occurrence patterns were studied at the global and local scales. The latter show cases of aggregation (between the black rat and native species, for instance) and of segregation (as between the house mouse and the black rat in Tambacounda, or between the black rat and M. natalensis in Kédougou). While updating information on commensal small mammal distribution in Senegal, a country submitted to a dynamic process of invasion by the black rat and the house mouse, we bring original information on how species occupy and share the commensal space, and make predictions on the evolution of these communities in a period of ever-accelerating global changes.

Mapping small mammal optimal habitats using satellite-derived proxy variables and species distribution models.

Small mammal species play an important role influencing vegetation primary productivity and plant species composition, seed dispersal, soil structure, and as predator and/or prey species. Species which experience population dynamics cycles can, at high population phases, heavily impact agricultural sectors and promote rodent-borne disease transmission. To better understand the drivers behind small mammal distributions and abundances, and how these differ for individual species, it is necessary to characterise landscape variables important for the life cycles of the species in question. In this study, a suite of Earth observation derived metrics quantifying landscape characteristics and dynamics, and in-situ small mammal trapline and transect survey data, are used to generate random forest species distribution models for nine small mammal species for study sites in Narati, China and Sary Mogul, Kyrgyzstan. These species distribution models identify the important landscape proxy variables driving species abundance and distributions, in turn identifying the optimal conditions for each species. The observed relationships differed between species, with the number of landscape proxy variables identified as important for each species ranging from 3 for Microtus gregalis at Sary Mogul, to 26 for Ellobius tancrei at Narati. Results indicate that grasslands were predicted to hold higher abundances of Microtus obscurus, E. tancrei and Marmota baibacina, forest areas hold higher abundances of Myodes centralis and Sorex asper, with mixed forest-grassland boundary areas and areas close to watercourses predicted to hold higher abundances of Apodemus uralensis and Sicista tianshanica. Localised variability in vegetation and wetness conditions, as well as presence of certain habitat types, are also shown to influence these small mammal species abundances. Predictive application of the Random Forest (RF) models identified spatial hot-spots of high abundance, with model validation producing R2 values between 0.670 for M. gregalis transect data at Sary Mogul to 0.939 for E. tancrei transect data at Narati. This enhances previous work whereby optimal habitat was defined simply as presence of a given land cover type, and instead defines optimal habitat via a combination of important landscape dynamic variables, moving from a human-defined to species-defined perspective of optimal habitat. The species distribution models demonstrate differing distributions and abundances of host species across the study areas, utilising the strengths of Earth observation data to improve our understanding of landscape and ecological linkages to small mammal distributions and abundances.

Small mammals of a northern salt-affected grassland

Abstract While many studies have characterized small mammals of the southern and central Great Plains (USA), far fewer have documented small mammals of the northern Great Plains which differ dramatically in plant structure and composition. We examined the presence and distribution of small mammals captured at a salinity-affected grassland in northeastern North Dakota (2018–2021). We captured 12 species from 8 genera including Microtus pennsylvanicus (n = 724), Peromyscus (maniculatus) sonoriensis (n = 114), Sorex cinereus (n = 54), and Zapus hudsonius (n = 43). We evaluated the extent to which these species varied with plant and environmental characteristics. M. pennsylvanicus was positively associated with plant cover and soil moisture and P. (maniculatus) sonoriensis was positively associated with forb cover and negatively associated with litter and elevation. Z. hudsonius was negatively associated with forb cover and soil moisture and S. cinereus was positively associated with cover and negatively associated with salinity. These species associated with their environments differently than their more southern counterparts and reinforce the notion that not all areas, even in relatively intact grasslands, are available to all species. Future studies are needed to further examine more infrequently captured species, including a Sorex hoyi, an Onychomys leucogaster, and eight Myodes gapperi in this region.

Indirect Human Influences in Fear Landscapes: Varying Effects of Moonlight on Small Mammal Activity along Man-Made Gradients of Vegetation Structure

Risk of predation is one of the main constraints of small mammal distribution and foraging activity. Aside from numerical effects on population size due to the presence and abundance of predators, indirect cues, such as vegetation structure and moonlight, determine patterns of activity and microhabitat use by small mammals. Indirect cues are expected to interact, as shading provided by vegetation can suppress the effects of changing moonlight. We analyzed the effects of moonlight levels on the activity patterns of three common small mammal species in Mediterranean habitats, and tested whether moonlight effects were modulated by shadowing associated with the development of tall vegetation due to spontaneous afforestation following land abandonment. A. sylvaticus, a strictly nocturnal species, decreased activity under moonlight with no interactive effects of vegetation cover. C. russula showed no activity change with moonlight levels and M. spretus increased activity, although activity in both species was mostly determined by vegetation cover, that favored it. The effects of moonlight on small mammal activity were not homogeneous among species, nor were the interactive effects of man-made gradients of habitat structure, a fact that will produce community changes along vegetation gradients mediated by varying fear landscapes.

Mammals in Tawny Owl (Strixaluco) pellets from Kharkiv Region, Ukraine.

The Tawny owl (Strixaluco) is a common owl species in Europe, demonstrating generalist diet strategy. Its main prey are small rodents and numerous studies show that the composition of its diet broadly reflects changes in prey species abundance in its habitats. Due to strictly sedentary habits of adult birds and their year-round territoriality, it is possible to locate habitats of their prey with a precision of several hundred metres. Analysis of owl pellets is a traditional method in faunistic studies to provide data on distribution of small mammals, especially cryptic species which are hard to be found using trapping. Here, we present a dataset on mammals found in Tawny owl pellets collected during up to 13-year studies in the Kharkiv Region, Ukraine in three territories. Data from two territories were collected in a systematic way and allowed us to make analysis of seasonal, year-to-year and habitat variability in the Tawny owl diet and local mammal species composition.

An ecoregionalization of the Sierra Madre Occidental, México, based on non-volant, small mammal distributions

ABSTRACT The Sierra Madre Occidental (SMO) is the largest mountain range in Mexico, spanning nearly 1,400 km from northwest to southeast. It is a region of high ecological complexity, yet, few attempts at ecoregionalization are available. Using Maxent and five high-resolution (30 m) physiographic layers, we generated niche models for 33 species of small, non-flying mammals. We generated a proposal of regions based on the proportion of overlap of all possible pairs of species niches (ordinated using PCoA) and environmental data. We compared the resulting ecoregionalization with the most detailed regionalizations of the SMO available, based on floristic, vegetational, and bird distribution data. PCoA revealed two major axes of variation related to elevation and humidity, and therefore to vegetational composition. Our regionalization is consistent with previous regionalizations in recognizing a tropical and a xerophilous region, but not a transitional Madrean Tropical. We identified the highlands as a north-south continuum, and a transitional region was identified between the xerophilous and highland areas. Differences in ecoregional patterns in taxa as different as mammals and plants, are evidence that the SMO’s complexity goes beyond the more traditional Nearctic-Neotropical subdivision.

Distribution of Four Vole Species through the Barn Owl Tyto alba Diet Spectrum: Pattern Responses to Environmental Gradients in Intensive Agroecosystems of Central Greece.

Voles are the most common vertebrate pests in European agriculture. Identifying their distribution and abundance patterns provides valuable information for future management. Barn Owl diet analysis is one of the optimum methods used to record small mammal distribution patterns on large spatial scales. From 2003 to 2005, a total of 10,065 Barn Owl pellets were collected and analyzed from 31 breeding sites in the largest agroecosystem in Greece, the Thessaly plains. A total of 29,061 prey items were identified, offering deep insight into small mammal distribution, specifically voles. Four discrete vole species (Harting's vole Microtus hartingi, East European vole Microtus levis, Thomas's pine vole Microtus thomasi, and Grey dwarf hamster Cricetulus migratorius) comprised 40.5% (11,770 vole prey items) of the total Barn Owl prey intake. The presence and abundance of the voles varied according to underlying environmental gradients, with soil texture and type playing a major role. M. levis showed no significant attachments to gradients, other than a mild increase in Mollisol soils. It was syntopic in all sites with M. hartingi, which was the dominant and most abundant small mammal species, preferring non-arable cultivated land, natural grasslands, set-aside fields, and fallow land. M. thomasi was strictly present in western Thessaly and strongly associated with a sandy-clay soil texture and Alfisol soils. C. migratorius was the least represented vole (162 items), exclusively present in eastern Thessaly and demonstrating a stronger association with cereals, Mollisol soils, and an argillaceous-clay soil texture. This is the first study in Greece at such a large spatial scale, offering insights for pest rodents' distribution in intensive agroecosystems and their response to environmental gradients including soil parameters.

An updated biogeographic evaluation of endemism and conservation of small mammals from Chile

AbstractEcological factors such as temperature, precipitation, and vegetation type have been reported to influence biogeographic patterns (e.g., species distribution, richness, and endemism) in mammals. In Chile, these patterns only had been explored in selected mammal groups from certain localities. In this study, we describe and analyze biogeographic patterns for all small mammals (marsupials, armadillos, bats, rodents), reported until 2020, in different climatic and ecological regions from continental Chile. Using a compiled database of 89 species, we estimated their distributional similarity, described and characterized richness and areas of endemism using Bayesian and Parsimony Analysis of Endemism, and linked species distribution with conservation status according to the IUCN Red List. We found three similarity units of species distribution based on climate: Arid, Temperate, and Polar; higher richness and endemism in north and south-central Chile; two areas of endemism, one in north and one in south; and a hotspot in south-central Chile. Finally, species of greater conservation concern showed a similar and small distribution range. The concordance in the distribution of the species with Chilean climatic regions (as determined by precipitation and temperature) suggest that the spatial distribution of Chilean small mammals is influenced strongly by those abiotic factors. This also could explain the patterns of richness and endemism and, therefore species hotspots. Variations of climatic factors therefore should be considered in explaining biogeographic patterns and conservation plans of Chilean small mammal species, because species of greater concern tend to be associated and having similar distributional characteristics.

DIVERSITY OF NON-VOLANT SMALL MAMMALS IN PULAU TINGGI, JOHOR, MALAYSIA

A non-volant small mammal survey was conducted at Pulau Tinggi between July and September 2019. This study aimed to provide baseline data for non-volant small mammals in Pulau Tinggi by setting 55 cage traps and 20 pitfalls for 44 trapping nights. A total of 20 individuals of non-volant small mammals were documented, representing five species from three families: Soricidae, Sciuridae and Muridae. The Rajah spiny rat (Maxomys rajah) and the Red spiny rat (Maxomys surifer) were the most abundant species (n=6) of non-volant small mammals in Pulau Tinggi. The Malayan field rat (Rattus tiomanicus) was the least species (n=1). The Malayan shrew (Crocidura malayana) is the only shrew recorded on the island. The analysis of similarities between our study site and other Malaysian islands reveals that Pulau Tinggi shares more similarities with Pulau Pangkor and Pulau Perhentian than Pulau Tioman. The small mammal richness on Pulau Tinggi is relatively low compared to other islands, most likely due to the study site’s limited coverage and time constraints. Long-term monitoring is required to determine the true diversity of species and distribution of small mammals on Pulau Tinggi.

First record of a least weasel in Nunavik

The spatial distributions of several small mammals in Nunavik, Québec, Canada, currently do not rely on any recorded observations due to the rarity of wildlife surveys in that area. This is concerning because understanding changes in wildlife populations in response to the rapidly warming Arctic requires knowledge of prior population states. On 18 July 2021, my assistant and I captured a least weasel ( Mustela nivalis Linnaeus, 1766) alive, 11 km southwest of Salluit during a live-trapping session of lemmings and voles. Identification was done with the small body mass (44 g), the presence of prominent testicles indicating maturity, short length of the tail, and pale colour at the tip of the tail. All these criteria combined fit only the description of least weasels. According to the available records for this species, this observation is the first one confirmed in Nunavik. This Low Arctic area was already included in the species distribution described in the literature, but no record supported it up to now. It is of particular importance considering this species is susceptible to be designated as threatened or vulnerable in the province of Quebec according to the Centre de données sur le patrimoine naturel du Québec.

Vegetation cover and spatial distribution of small mammals in the conditions of woodland large city park (Nizhny Novgorod)

The paper is devoted to the study of ecological connectivity vegetation cover and microtine rodents spatial distribution in the conditions of the Nizhny Novgorod woodland park. The oak forest of National Research Lobachevsky State University of Nizhny Novgorod Botanical Garden with partial anthropogenic transformation was chosen as a site of the study. We used five various plant communities represented by linden trees. The dominant in all ecosystems on the test areas is the red vole (73%), the codominant is the pygmy wood mouse (21%). The yellow-necked mouse has been observed only in several communities. It has been revealed that a decrease in the biodiversity of plant communities due to an increase in the degree of individual species dominance marked by BergerParker index doesnt entail significant negative consequences for small mammals. It is possible that the dominants in vegetation cover create a favorable microclimate for small mammals. The PCA analysis shows the presence of two significant factors for the distribution of microtine rodents. The first factor is associated with the balance of humidity and illumination, the second with nitrogen availability in combination with low illumination. The ecological divergence of niches in two species of mice (pygmy wood mouse and yellow-necked mouse) was observed. In relation to the projective cover, the bank vole occurs both at very high (90%) and low (30%) values, which confirms the ecological plasticity of that species. For yellow-necked and pygmy wood mice, the optimal values of projective cover in studied communities range from 70 to 90%. However, yellow-necked mice can also live in plant communities with a plant cover index about 4050%.

Human Disturbance and Geometric Constraints Drive Small Mammal Diversity and Community Structure along an Elevational Gradient in Eastern China.

Simple SummaryBiodiversity patterns and mechanisms along elevational gradients have long been the focus of conservation research. However, few studies have been conducted in mountainous areas of eastern China, especially for small mammals. In this study, we used a standard sampling method to survey small mammals along the gradient of Qingliang Mountain in eastern China and analyzed the patterns and mechanisms of diversity and community structure. We found inconsistencies between different diversity dimensions. Functional and phylogenetic structures were mainly clustered but showed opposite elevation patterns. Human disturbance and MDE were the main drivers of the diversity patterns, but with contrasting effects on different dimensions. These findings emphasize the importance of a multiple dimensions approach to biodiversity conservation and call for increased conservation efforts in the low and middle elevation regions.Understanding the mechanisms influencing patterns and processes of biological diversity is critical to protecting biodiversity, particularly in species-rich ecosystems such as mountains. Even so, there is limited knowledge of biodiversity patterns and processes in the mountains of eastern China, especially about small mammals. In this study, we examined the taxonomic, functional, and phylogenetic diversity of small mammal distribution and community structure along the elevational gradient of Qingliang Mountain, eastern China. We then evaluated how they are influenced by space (area and mid-domain effect (MDE)), environment (temperature, precipitation, and normalized difference vegetation index (NDVI)), and human disturbance. The results showed hump-shaped patterns of taxonomic and phylogenetic diversity along elevation gradients, peaking at 1000 m, unlike functional diversity, which peaked at lower elevations (600 m). The mean pairwise distance and mean nearest taxon distance of functional and phylogenetic variance (MFD and MPD, respectively) were also incongruent. The MFD and MPD showed hump-shaped patterns along elevations; however, unlike MFD, which peaked at lower elevations (600 m), MPD peaked at higher elevations (1200 m). The mean nearest functional taxon distance (MNFD) decreased, while the mean nearest phylogenetic taxon distance (MNTD) increased along the elevation gradient. The higher elevations were functionally more clustered, while the lower elevations were phylogenetically more clustered, suggesting that environmental filtering for traits was stronger at higher elevations. In comparison, phylogenetic conservatism of ecological niches had a stronger influence at lower elevations. The diversity and community structure indices were inconsistently explained, with human disturbance and MDE accounting for the biggest proportions of the model-explained variances. Overall, the results confirm that environmental filtering and human disturbance significantly influence small mammals’ diversity and community structure. These findings also emphasize the need for increased conservation efforts in the middle and lower elevation regions of Qingliang Mountain.

A Decade-Long Change in the Elevational Distribution of Non-Volant Small Mammals on Mount Meru, Tanzania

Understanding species distribution across elevational gradients is crucial for developing conservation strategies for montane biotic systems. A survey of small mammals was conducted on Mount Meru at six elevations, ranging between 1500 m and 3650 m. A total of 803 small mammal individuals, including 2 shrew species and 13 rodent species, were documented. Of these, Crocidura newmarki and Lophuromys verhageni were endemic on Mount Meru. Species richness was highest at mid–elevations, which is in line with the global pattern for small mammals. Prior to our study, the most complete data on small mammals on Mount Meru was collected in 2009. Our study provides an opportunity to show how small mammal elevational distribution has changed, over the last decade. We found six species (Arvicanthis niloticus, Mastomys natalensis, Lemniscomys striatus, Dasymys incomtus, Cricetomys ansorgei, and Montemys delectorum), which were not documented in 2009, but did not find Otomys tropicalis. Interestingly, the community composition at higher elevations in 2021 resembles that at lower elevations in 2009, suggesting that small mammal species have moved their range upward over time. Climate change could be a factor associated with the distributional shift found.

Changing land cover and small mammal habitats: Implications for landscape ecological integrity

This paper adds to the landscape ecological integrity (LEI) literature by emphasising the need to move beyond the assumption of a linear relationship between fragmentation metrics and ecological integrity. This study argues that such a relationship is weak or even non-existent when not associated with specific species or ecological process. Thus, using the Greater Accra Region of Ghana as a case, this study assessed the quality and spatio-temporal distribution of terrestrial small mammal habitats, as influenced by changing land cover, highlighting the implications for LEI. First, the study used fragmentation statistics to model changing land cover from 1986 to 2020. This was followed by the use of the Leo Breiman's random forest algorithm to predict small mammal distribution in the same period. The results showed that normalized difference vegetation index (NDVI) has a high predictive importance on small mammal distribution. Decreasing the vegetated areas does not necessarily lead to a decrease in species habitats. However, the decreasing forest areas and shrub-lands leads to a statistically significant increase in small mammal population in built-up areas while their population reduced within farmlands. The paper concludes that an increase in small mammal habitats in built-up areas does mean improved landscape ecological health, considering that these built-up areas are not natural abodes.

Distribution and functional traits of small mammals across the Mediterranean area: landscape composition and structure definitively matter

• Small mammals’ taxonomic and functional composition vary with landscape pattern. • Species assemblages tend to be simpler in anthropogenic landscapes. • Seminatural and anthropogenic landscapes influence functional composition. • Understanding community assembly could help prioritise conservation actions. Mediterranean landscapes constitute a biodiversity hotspot where species distribution and composition have been shaped by a long history of traditional land use. In this work, we investigated the effects of landscape patterns on community composition and the functional, morphological, and ecological traits of 21 small mammal species in the Mediterranean region. We extracted species abundance and trait data from 86 georeferenced Common Barn-owl pellet sites collected in Central Italy, covering 33,000 km 2 , and stored in the OpenMICE database. Additionally, we measured 12 landscape metrics on land cover maps produced at intervals coeval with pellet collection dates. We explored the variation in species composition against landscape pattern metrics using canonical correspondence analysis (CCA). Moreover, we analysed the relationships among small mammals’ occurrence, their life history traits, and landscape pattern metrics using the fourth-corner model approach. Our results highlighted the key role of landscape composition and configuration in shaping small mammal species composition and their functional traits. Species and trait composition varied along two main landscape gradients, with a simplification of species assemblage towards increasing human pressure (i.e., artificial surfaces and agricultural areas) and decreasing cover of seminatural areas. The observed variability of species assemblages and functional traits across Mediterranean landscape gradients highlights the need to preserve diverse ecosystems and land cover types to maintain small mammal biodiversity and related ecosystem functioning.

Small mammal species diversity and distribution in the Selous ecosystem, Tanzania

Threats to ecosystems are ever increasing from different drivers mostly being linked to anthropogenic activities. This has brought about various measures to restore/protect the wildlife in these areas. Considering the background of most protected areas in East Africa, small mammals have been given least attention, compared with large mammals, although they play a fundamental role in maintaining ecosystem health. It is therefore necessary to understand how small mammals are distributed in any given ecosystem as a baseline information to enable holistic and informed management. We investigated the diversity and distribution of small mammals in the Selous ecosystem, Tanzania. Two methods were used; Capture Mark Recapture (CMR) using grids of 70 m x 70 m and random placement of havahart traps in the selected habitats. Between July 2018 and June 2020, a total of 887 individuals belonging to 20 species were captured in 28 224 trap nights with 3% trap success. The small mammal species captured consisted of rodents (91.8%), Macroscelidea (3.9%), Carnivores (2.4%) Eulipotyphla (1.6%), and Primates (0.3%). Acomys ngurni (36%) and Aethomys chrysophilus (17%) were the most captured species, whereas Atilax paludinosus (0.23%), Helogale pervula (0.23%), Rattus rattus (0.23%) and Galerella sanguinea (0.11%) were the least contributing species. Acomys ngurui and Lemniscomys rosalia were the most distributed species occurring in all four habitats, whereas Cricetomys ansorgei, Rattus rattus, Mungos mungo and Genetta genetta had low occurrence. Grammomys selousi is reported for the first time in the northern part of the Rufiji River. Acomys ngurni abundance differed significantly (χ2 = 12, df = 3, p = 0.007) between the four habitats being higher in the seasonal riverine forest and across seasons (χ2 = 6, df = 2, p = 0.049), with more individuals occurring in the wet season. The Sable Forest habitat had the highest species diversity (H' = 2.065) and the lowest diversity (H' = 1.506) was recorded in perennial riverine forest/thickets. The highest species diversity (H' = 1.65) was recorded in the dry season and the lowest diversity in the wet season (H' = 1.445). Most small mammals were associated with seasonal riverine forest than other habitats. Overall, the results from this study show that, the park is rich in small mammal fauna. Therefore, considerations in updating the General Management Plan (GMP) and other plans to include the small mammals in the park management actions is recommended.

Occurrence and Habitat Use of Non-native Small Mammals in Upland Urban-Forest Environment in Northern Philippines

In the Philippines, few researches have been conducted about small mammals in urban areas at high elevation, where forests remain and non-native pest species can proliferate. Previous studies in Baguio City, Benguet Province reported three non-native species. This study extended these prior surveys by sampling in 13 localities, employing standard trapping method to document the distribution of species in an urban-forest setting. In 4,711 trap nights, 94 individuals were captured, consisting of four non-native species: Rattus exulans, Rattus tanezumi, Mus musculus, and Suncus murinus. Analysis of occurrence and relative abundance of species showed that small mammal distribution varied among the habitats, and appeared that variation may have been related to differences in vegetation structure or a habitat’s disturbance level. Rattus tanezumi was the most widespread, being especially common in backyard farms and in the public market. Suncus murinus was also widespread but less abundant than R. tanezumi. Rattus exulans was uncommon and restricted to certain area of a given habitat, particularly preferring weed-dominated areas. These suggest that non-native species are common and widespread in urban-forest setting but with apparent habitat preferences. The non-detection of native species is notable, suggesting that thorough studies can be done in the future.

The effect of the character of urban development on the small mammal communities in a northern city

Communities of small mammals on the territory of Yakutsk and in its vicinity have been studied. Residential areas, undeveloped sites, suburban zone, and agricultural lands are covered. A total of 2,736 cone-days and 525 trap-days are accumulated and 388 specimens of small mammals from 13 species belonging to Rodentia and Eulipotyphla orders are collected. The abundance of small mammals in different types of environment have varied from 2.2 to 22.9 individuals per 100 cone-days. The highest values of species diversity are found in the suburban zone in the areas of surviving natural biotopes. The zone of the city’s residential areas is characterized by the lowest abundance and species diversity of small mammals, primarily Eulipotyphla, and also by the presence of eusynanthropicMus musculus and Rattus norvegicus. The undeveloped territories of the city are characterized by a high total abundance of small mammals, but poor community composition, which is close in its structure to floodplain biotopes. Communities of agrocenoses are also poor, due to elimination of forest species, and characterized by uneven distribution of small mammals among the biotopes. On the whole, the anthropogenic effect of urbanization is manifested in poor composition of communities and changes in the dominance structure. The appearance of the house mouse in the zone of detached housing indicates intensifying urbanization of the territory and ongoing synantropization of the fauna.