Species composition,abundance and habitat association of rodents and insectivores from Chilalo–Galama Mountain range,Arsi, Ethiopia

A study on the ecology of rodents and insectivores on Mount Chilalo and the Galama Mountain range was conducted during August, 2007–April, 2008. Study grids were marked in nine randomly selected habitats. Sherman live traps and snap traps were used to capture the small mammals. A total of 2525 (including recaptures) individual rodents and insectivores were captured in 5488 (Sherman) and 1590 (snap) trap‐nights. Among the live‐trapped animals, 2037 (96.2%) and 80 (3.8%) were rodents and insectivores, respectively, that comprised 17 species. These were as follows: Arvicanthis abyssinicus, Arvicanthis blicki, Arvicanthis dembeensis, Lophuromys flavopunctatus, Lophuromys melanonyx, Mastomys natalensis, Mus mahomet, Otomys typus, Rattus rattus, Stenocephalemys albipes, Stenocephalemys albocaudata, Stenocephalemys griseicauda, Crocidura glassi, Crocidura flavescens and Crocidura thalia. Tachyoryctes splendens and Hystrix cristata were sighted but not captured. Endemics to Ethiopia constituted 60% of the trapped small mammals. Lophuromys flavopunctatus was the most abundant and widely distributed rodent species, while M. mahomet was the least. The altitudes between 3301 and 3400 m asl had the highest species composition and abundance although it is second in number of catches per trap‐nights. The majority of rodents and insectivores were associated with montane forest habitat, whereas the least were in the shrubland. Anthropogenic effects were witnessed affecting the distribution of small mammals.     

Habitat occurrence and feeding ecology of Crocidura montis and Lophuromys flavopunctatus on Mt. Elgon, Uganda

The distribution, habitat occurrence and feeding ecology of Crocidura montis and Lophuromys flavopunctatus coexisting in the afro‐alpine zone on Mt. Elgon, Uganda, are described. Crocidura montis was the only shrew species occupying the afro‐alpine zone, but was not found in forested habitats below 3200 m. While there was considerable overlap in habitat occurrence between the two species, C. montis was most abundant in the montane grassland and in drier sites while L. flavopunctatus occupied a wider range of habitats and wetter sites. C. montis ate a diversity of invertebrates, the most important being Coleoptera, Araneae and Lumbricidae. Invertebrates, mostly Diptera larvae, Lumbricidae and Coleoptera, formed a major component of the L. flavopunctatus diets, plus plant material (particularly Hepaticae and monocots). The arthropod components of the diets reflected their abundance in pitfall samples.     

Small mammals of the Bale Mountains, Ethiopia

A sample of 535 small mammals, caught over a range of altitudes from 1500 to 4000 m in the Bale Mountains, on various expeditions from December 1971 to August 1986, enables the altitudinal zonation of the species to be delimited. The most abundant species, Lophuromys flavopunctatus, ranged from near the lower tree line at 1550 m, right up through the forested zones and onto the Afro-alpine moorland at 3900 m. The endemic Praomys albipes also ranged through the forest from 1550 to 3200 m, but was replaced in open habitats between 2400 and 3900 m by Stenocephalemys griseicauda and between 3000 and 4000 m by S. albocaudata, which was relatively more abundant than its congener at higher altitudes. Other moorland species, including Crocidura fumosa, Otomys typus, Lophuromys melanonyx and Arvicanthis blicki were also commonest at 3800–4000 m, but, like the Stenocephalemys spp., penetrated to lower altitudes in open habitats. Mus mahomet was confined to lower altitudes (1510–3000 m) and open habitats, apparently replaced by Mus triton, not previously recorded from Ethiopia, in forested habitats at middle altitudes (1950–2400 m).     

Distribution of small rodents and shrews in a lowland rain forest zone of Nigeria, with observations on their reproductive biology

This paper describes the habitat preferences of small rodents and shrews from April 1984 to March 1985 in four types of vegetation in a lowland rain forest zone of Nigeria. The vegetation types were high forest, scrub, farmlands and teak plantations in Ogba Forest Reserve, Nigeria. A collection of 359 small mammals, consisting of six species of small rodents and four species of shrews, was made in the study area. The small rodents and their percentage composition were Mus musculoides (26.2%), Praomys tullbergi (16.2%), Mastomys natalensis (7.0%), Lophuromys sikapusi (4.5%), Lemniscomys striatus (2.5%), and Arvicanthis niloticus (1.1%). The shrews were Crocidura nigeriae (19.5%), C. crossei (12.3%), C.grandiceps (7.8%) and C. ftavescens manni (3.1%). The vegetational distribution of the small rodents and shrews is discussed. In the high forest, seven species of small mammals were caught; these were Crocidura nigeriae, C. crossei, C.grandiceps, C.flavescens manni, Mus musculoides, Praomys tullbergi and Lophuromys sikapusi. Mus musculoides, Crocidura nigeriae and Praomys tullbergi were more abundant in the high forest. All the species of small mammals recorded in the study area, except Arvicanthis niloticus, were found in the scrub. In the farmlands, all ten species of small mammals were trapped. Mus musculoides was the commonest species in the farmlands. Three species of shrews, Crocidura crossei, C. grandiceps and C.flavescens manni, and also two species of small rodents, Mus musculoides and Mastomys natalensis were caught in the teak plantation. The reproductive data for Mus musculoides, Crocidura nigeriae and Praomys tullbergi show that breeding in these species occurs throughout most months of the year. Fecundity appears to be maximal in the wet season in Mus musculoides and Crocidura nigeriae and in the dry season in the case of Praomys tullbergi.     

Demography and habitat selection of small mammals on Zomba Plateau, Malawi

Small mammals were studied in tow montane grassland-forest areas on Zomba Plateau (1900m), Malawi, in 1984–85. Seasonal changes in numbers, age-structure and reproduction are given for the three commonest species. Mus triton (36%), Praomys delectorum (29%), and Lophuromys flavopunctatus (19%). Total population numbers for L. flavopunctatus and P. delectorum were lowest at the end of the dry season, and highest at the end of the wet season; reproduction is seasonal, and most young are born in the wet season. Mus triton did not exhibit such large fluctuations in numbers, and reproduced in both wet and early dry seasons. Each species was found in several habitats, but L. flavopunctatus showed a strong preference for unburnt grasslands, M. triton for burnt grasslands, and P. delectorum for forest and tangle habitats. Each species had a different population survival rate, and few individuals survived for more than 5–6 months. Trapped-revealed home ranges were about 3100 m² for L. flavopunctatus , and 2700 m² for M. triton . Monthly changes in grass biomass, cover and height were recorded and related to the numbers of small mammals. General features of the small mammals of African mountains, based on data from the Drakensberg, Ethiopia and this study. are presented.     

Species composition,abundance and habitat association of non-volant small mammals in Gibe Sheleko National Park,southwestern Ethiopia

The objective of this study was to assess the species composition, abundance and habitat association of non-volant small mammals from grassland, Acacia woodland, farmland, riverine forest, bushland and wooded grassland habitats in Gibe Sheleko National Park, southwestern Ethiopia. Data were collected using 49 Sherman live traps in 70 × 70 m sized girds and visual observations from December 2018 to August 2020. A total of 937 small mammals belonging to 10 species were captured and directly identified. The identified small mammal species and their relative abundance include Arvicanthis niloticus (7.04%), Crocidura olivieri (1.92%), Grammomys dolichurus (3.84%), Lemniscomys striatus (10.25%), Mastomys awashensis (24.55%), Mastomys natalensis (33.83%), Mus tenellus (0.85%), Myomys fumatus (6.30%), Rattus rattus (4.70%) and Stenocephalemys albipes (6.72%). Hystrix cristata, Xerus rutilus and Tachyoryctes splendens were documented through observation. The highest number of species (6) was registered at farmland and wooded grassland followed by bushland and riverine forest (5) and Acacia woodland and grassland (4). Lemniscomys striatus, M. awashensis and M. natalensis were common in all habitats. More, 216 (23.05%) individuals were recorded in farmland, while the least, 111 (11.85%) were recorded in Acacia woodland. The study area has various topographical land settings additional study is needed using different traps.     

Species composition and community structure of small pest rodents (Muridae) in cultivated and fallow fields in maize‐growing areas in Mayuge district,Eastern Uganda

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Ecology of a typical West African Sudanian savannah rodent community

The small‐mammal community of a typical Sudanian savannah area of south‐eastern Senegal was studied by way of intensive sampling at the beginning (July) and at the end (November) of the rainy season. A total of 5931 trapnights and 200 pitfallnights yielded 767 small mammals, including 757 rodents of 12 species, as well as a few shrews and hedgehogs. Accumulation curve indicated that the rodent community was well sampled. Murine rodents were far more numerous than gerbilline rodents, and among them, Mastomys erythroleucus was the dominant species, being caught in high numbers in all habitats. Arvicanthis niloticus and Praomys daltoni were also abundant, followed by Mastomys natalensis and Gerbilliscus guineae. Abundances were high at the beginning of the rainy season when reproductive activity was low in all species. At the end of the rainy season, murine rodents were actively involved in reproduction, while gerbilline rodents were at their lowest density. Significant changes in relative abundance among habitats (including human dwellings) were observed between periods in some species, suggesting seasonal trends in habitat preferences. This may help species coexistence in this species‐rich rodent community, in an area likely to be submitted to significant habitat alterations in the years to come.     

Species diversity and abundance of small mammals in Nechisar National Park,Ethiopia

Species diversity and abundance of small mammals were studied in Nechisar National Park, Ethiopia, during August 2008 – March 2009. Twenty species of rodents and four species of insectivores were recorded from the study area. Mastomys natalensis (17.37%), Arvicanthis dembeensis (17.09%), Mastomys erythroleucus (8.90%), Stenocephalemys albipes (8.76%), Arvicanthis niloticus (8.19%), Acomys cahirinus (7.34%), Lemniscomys striatus (6.92%), Gerbilliscus nigricauda (6.21%), Grammomys dolichurus (3.67%), Gerbilliscus robusta (2.12%), Mus proconodon (1.98%), Mus mahomet (1.41), Dendromus melanotis (1.27%), Arvicanthis abyssinicus (1.13%), Mus musculus (0.99%), Praomys fumatus (0.85%), Xerus erythropus (0.85%), Lemniscomys barbarus (0.71%), Mus tenellus (0.71%) and Otomys typus (0.28%) were the rodents and their respective relative abundance in the study area. Crocidura olivieri (1.55%), Crocidura fumosa (0.85%), Crocidura bicolor (0.57%) and Elephantulus rufescens (0.28%) were the insectivores recorded with their respective relative abundance. Mastomys natalensis was the most abundant and O. typus and E. rufescens were the least (two each). Diversity of small mammals ranged from 2.299 to 2.625 with an average of 2.412. The highest small mammal diversity was in grasslands and the lowest was in Lake Chamo shore. Small mammal density varied from 5 to 43 ha^?1 and biomass varied from 244 to 2559 g ha^?1 with significant changes in relation to seasons and habitats.     

Diversity patterns of small mammals in the Zambales Mts., Luzon, Philippines

In 2004 and 2005, we conducted a survey of the small mammals on Mt. Tapulao (=Mt. High Peak, 2037 m) in the Zambales Mountains, Luzon Island, Philippines in order to obtain the first information on the mammals of this newly discovered center of endemism. We also tested two hypotheses regarding the relationship of species richness with elevation and the impact of alien species on native mammals. The survey covered five localities representing habitats from regenerating lowland rain forest at 860 m to mossy rain forest near the peak at 2024 m. We recorded 11 species, including 1 native shrew, 1 alien shrew, 8 native rodents, and 1 alien rodent. Two species of Apomys and one species of Rhynchomys are endemic to Zambales; this establishes the Zambales Mountains as a significant center of mammalian endemism. Species richness of native small mammals increased with elevation, from five species in the lowlands at 925 m to seven species in mossy forest at 2024 m; total relative abundance of native small mammals increased from 925 to 1690 m, then declined at 2024 m. Alien small mammals were restricted to highly disturbed areas. Our results support the prediction that maximum species richness of small mammals would occur in lower mossy forest near the peak, not near the center of the gradient. Our results also support the hypothesis that when a diverse community of native Philippine small mammals is present in either old-growth or disturbed forest habitat, “invasive” alien species are unable to penetrate and maintain significant populations in forest.     

Sea level rise may increase extinction risk of a saltmarsh ontogenetic habitat specialist

Specialist species are more vulnerable to environmental change than generalist species. For species with ontogenetic niche shifts, specialization may occur at a particular life stage making those stages more susceptible to environmental change. In the salt marshes in the northeast U.S., accelerated sea level rise is shifting vegetation patterns from flood‐intolerant species such as Spartina patens to the flood‐tolerant Spartina alterniflora. We tested the potential impact of this change on the coffee bean snail, Melampus bidentatus, a numerically dominant benthic invertebrate with an ontogenetic niche shift. From a survey of eight marshes throughout the northeast U.S., small snails were found primarily in S. patens habitats, and large snails were found primarily in stunted S. alterniflora habitats. When transplanted into stunted S. alterniflora, small snails suffered significantly higher mortality relative to those in S. patens habitats; adult snail survivorship was similar between habitats. Because other habitats were not interchangeable with S. patens for young snails, these results suggest that Melampus is an ontogenetic specialist where young snails are habitat specialists and adult snails are habitat generalists. Temperature was significantly higher and relative humidity significantly lower in stunted S. alterniflora than in S. patens. These data suggest that thermal and desiccation stress restricted young snails to S. patens habitat, which has high stem density and a layer of thatch that protects snails from environmental stress. Other authors predict that if salt marshes in the northeast U.S. are unable to migrate landward, sea level rise will eliminate S. patens habitats. We suggest that if a salt marsh loses its S. patens habitats, it will also lose its coffee bean snails. Our results demonstrate the need to consider individual life stages when determining a species’ vulnerability to global change.     

Abundance responses of frugivorous bats (Stenodermatinae) to coffee cultivation and selective logging practices in mountainous central Veracruz,Mexico

Shifting and permanent cultivation, selective logging, cattle production and coffee plantations are among the most important factors in montane cloud forest conversion and disturbance. Although shaded-coffee plantations can contribute to the preservation of local species richness, abundance of organisms could be determined by habitat resource availability in agricultural landscapes. We compared abundance of Sturnira and Artibeus bats (Phyllostomidae, Stenodermatinae), in shade coffee plantations and disturbed cloud forest fragments, which represent habitats with different chiropterochorous plant density. We also investigated the relationship between bat species abundance and food plant richness, abundance and diversity. We captured 956 bats, 76% in cloud forest fragments and 24% in shaded coffee plantations. Abundance of Sturnira spp. (small bats) was greater in cloud forest than in coffee plantations, but Artibeus spp. (large bats) abundance was similar in both habitats. Chiropterochorous plant abundance was positively related with bat abundance for Sturnira spp., while chiropterochorous plant richness and diversity were negatively related for Artibeus spp. This suggests that frugivorous bats with different morphological and ecological characteristics respond differentially to anthropogenic activities. For landscape management purposes, the maintenance and augmentation of diverse food resources, for frugivorous bats with different foraging requirements in coffee plantations, will benefit the resilience of bats to modification of their natural habitat.     

Avian species diversity in different habitat types in and around North Nandi Forest,Kenya

Forest fragmentation and degradation leads to formation of modified habitats whose ability to support existing avifaunal diversity is still largely unknown. Bird diversity in indigenous forest, disturbed forest, plantation forest and farmlands adjacent to North Nandi Forest reserve was studied between January 2015 and June 2015. The distribution of bird feeding guilds in these habitat patches was also evaluated. Birds were surveyed using point counts, timed species counts and line transects and classified into six feeding guilds. A total of 3,232 individual birds of 151 species were recorded in the four habitats. Significant difference on bird abundance across the four habitats (F = 15.141, P ≤ 0.05, df = 3, 1121) was noted. Shannon–Weiner diversity index H′ for bird community ranged from 3.06 for plantation forest to 4.05 for disturbed forest showing a relatively diverse bird community. Insectivores (F = 3.090, P ≤ 0.05, df = 3, 297) dominated the foraging species assemblage in all the habitats significantly. Linear regression analysis revealed a strong linear relationship on bird species richness and abundance with vegetation variables (P < 0.01 in all cases). The results indicate that disturbed forest and indigenous forest support high bird species richness than plantation forest and farmlands. However, high bird abundance was observed in farmlands and plantation forest as opposed to indigenous forest and disturbed forest as they provide dispersal routes over a short distance and are important for creating corridors between primary forests.     

Diversity of rodents and shrews along an elevational gradient in Bwindi Impenetrable National Park, south-western Uganda

Small mammal species diversity in the major vegetation zones of Bwindi Impenetrable National Park is discussed in relation to altitude. Species richness of the small mammals was found to decrease with an increase in altitude. The main factors accounting for the observed diversity are the wide altitudinal variation and a complex array of vegetation types. Sixty‐seven species of rodents and shrews were found to exist in the Park; 47 of which were rodents and 20 shrews. Of these, 26 species are new to the Bwindi Park list. Three species have probably not been described before. The study found 10 species of small mammals to be Albertine Rift endemics. Three genera are recorded in Uganda for the first time: Rwenzorisorex, Suncus and Paracrocidura. Five species are new records for East Africa. These are Crocidura stenocephala, Lophuromys rahmi, L. medicaudatus, Paracrocidura maxima and Hylomyscus aeta. Because of the high endemism of plants, butterflies, birds and now of small mammal species, Bwindi forest is a unique biodiversity hotspot and is among the highest conservation priorities in the Albertine Rift.     

Bird Populations in Rustic and Planted Shade Coffee Plantations of Eastern Chiapas, México

Much of the remaining “forest” vegetation in eastern Chiapas, Mexico is managed for coffee production. In this region coffee is grown under either the canopy of natural forest or under a planted canopy dominated by Inga spp. Despite the large differences in diversity of dominant plant species, both planted and rustic shade coffee plantations support a high overall diversity of bird species; we recorded approximately 105 species in each plantation type on fixed radius point counts. We accumulated a combined species list of 180 species on repeatedly surveyed transects through both coffee plantation types. These values are exceeded regionally only by moist tropical forest. Of the habitats surveyed, shade coffee was second only to acacia groves in the abundance and diversity of Nearctic migrants. The two plantation types have similar bird species lists and both are similar in composition to the dominant woodland—mixed pine-oak. Both types of shade coffee plantation habitats differ from other local habitats in supporting highly seasonal bird populations. Survey numbers almost double during the dry season—an increase that is found in omnivorous migrants and omnivorous, frugivorous, and nectarivorous resident species. Particularly large influxes were found for Tennessee warblers (Vermivora peregrina) and northern orioles (Icterus galbula) in Inga dominated plantations.     

Survival and Growth of Juvenile Bromeliads in Coffee Plantations and Forests in Central Veracruz,Mexico

Shade coffee plantations can be important refuges for epiphytes, but are not suitable for all species. To test if the performance of early life stages, often the most sensitive phase, is responsible for the species’ ability to colonize coffee plantations, we compared growth and mortality rates of three epiphytic bromeliad species that differ in their ability to colonize secondary arboreal vegetation by transplanting juveniles to trees in forests, and shade trees in old and young coffee plantations in Central Veracruz, Mexico. Growth rates of Tillandsia viridiflora, generally restricted to forests, and Tillandsia juncea, an early colonizer, were related to the pattern of the species occurrence among habitats with growth rates of T. viridiflora being generally higher in forests and growth of T. juncea higher in coffee plantations. Performance of the third species, Tillandsia heterophylla, which is intermediate in habitat preference, was not clearly related to habitat. No difference in growth rates was found between plants transplanted in wet or dry season. In general, mortality in transplanted bromeliads was relatively low (mostly < 5% per month). In coffee plantations herbivory had a severe effect during part of the wet season, when mortality in young coffee plantations reached between 15 and 24 percent per month. Given the substantial contribution of herbivory to the mortality of juvenile plants and the significant differences between habitats, herbivory may be co‐limiting the colonization of young coffee plantations by some epiphytic bromeliads.     

Effects of habitat,season, and age on winter fat storage by migrant and resident birds in Jamaica

Most small birds wintering in the tropics should show little subcutaneous fat deposition (SFD), except in habitats where food availability may decline in late winter or, for some resident species, to prepare for incubation or brooding fasts. However, these predictions need re‐examination in light of a new, precise, cross‐validated method to compare SFD among habitats and species. We sampled 170 Nearctic‐Neotropical migrant and 279 resident birds during early and late winter in 1993 and 1994 in Jamaica, West Indies. Habitats, from greatest to least expected availability of insect prey, were (1) mangrove forest, (2) montane/foothills forest and cultivation, (3) dry limestone forest, and (4) acacia scrub. Percent lipid, estimated from multiple‐regression models using visual fat scoring (0–8 scale), total‐body electrical conductivity, and a variety of morphometrics, was categorized by percentile ranks to determine if SFD varied by habitat, season, or age for all species, resident species, migrant species, and several individual species. SFD averaged ~ 13% total mass for all birds, ranging from 8–24% for well‐sampled species. The few bird species in acacia scrub, primarily two facultative long‐distance migrants, averaged ~ 26% lipid content, significantly more than birds in other habitats. Most birds did not vary in SFD in the other three habitats, although Common Yellowthroats (Geothlypis trichas) had greater SFD in dry limestone habitat than in montane habitat. Bananaquits (Coereba flaveola) and Jamaican Euphonias (Euphonia jamaica) in montane habitat, especially in early winter, had higher SFD than other resident species. Contrary to our prediction, adults and juveniles had similar SFD, with the exception of juveniles having more SFD than adults in acacia scrub habitat. Winter fat deposition (or, in some cases, muscle‐protein catabolism) in the tropics may be an overlooked strategy, potentially important as a hedge against fasting for floaters, facultative migrants, some territorial migrants in habitats with seasonal declines in food resources, and some resident species prior to breeding.     

First Detection of Mycobacteria in African Rodents and Insectivores, Using Stratified Pool Screening

With the rising number of patients with human immunodeficiency virus (HIV)/AIDS in developing countries, the control of mycobacteria is of growing importance. Previous studies have shown that rodents and insectivores are carriers of mycobacteria. However, it is not clear how widespread mycobacteria are in these animals and what their role is in spreading them. Therefore, the prevalence of mycobacteria in rodents and insectivores was studied in and around Morogoro, Tanzania. Live rodents were trapped, with three types of live traps, in three habitats. Pieces of organs were pooled per habitat, species, and organ type (stratified pooling); these sample pools were examined for the presence of mycobacteria by PCR, microscopy, and culture methods. The mycobacterial isolates were identified using phenotypic techniques and sequencing. In total, 708 small mammals were collected, 31 of which were shrews. By pool prevalence estimation, 2.65% of the animals were carriers of mycobacteria, with a higher prevalence in the urban areas and in Cricetomys gambianus and the insectivore Crocidura hirta. Nontuberculous mycobacteria (Mycobacterium chimaera, M. intracellulare, M. arupense, M. parascrofulaceum, and Mycobacterium spp.) were isolated from C. gambianus, Mastomys natalensis, and C. hirta. This study is the first to report findings of mycobacteria in African rodents and insectivores and the first in mycobacterial ecology to estimate the prevalence of mycobacteria after stratified pool screening. The fact that small mammals in urban areas carry more mycobacteria than those in the fields and that potentially pathogenic mycobacteria were isolated identifies a risk for other animals and humans, especially HIV/AIDS patients, that have a weakened immune system.     

Species diversity and population dynamics of rodents in a farm‐fallow field mosaic system in Central Tanzania

A Capture‐Mark‐Recapture study was undertaken in Central Tanzania to compare variations in community structure and population dynamics of rodents in two types of habitats. The study was conducted in fallow field mosaic habitat dominated by perennial and annual grasses (grid BEA) and a more heterogeneous habitat (grid BEB) which was previously woodland cleared of most trees with vegetation dominated by shrubs, bushes, scattered trees and perennial grass. The relative abundance of rodents in BEA was: Mastomys natalensis (73.5%) > Aethomys chrysophilus (8.9%) > Gerbilliscus vicina (7.3%) > Arvicanthis neumanni (6.1%) > Acomys spinosissimus (4.1%) and for grid BEB: M. natalensis (67.6%) > G. vicina (11.2%) > A. neumanni (10.3%) > A. chrysophilus (7.6%) > A. spinosissimus (2.9%). Graphiurus sp., Mus minutoides, Saccostomus mearnsi, Lemniscomys striatus and L. griselda were rare and only occasionally trapped in BEB. Spatial variations in population density were non‐significant except for A. chrysophilus. Significant temporal variations within grids were observed, with synchrony of population peaks for some species. The rare species boosted species richness of grid BEB rather artificially, without significantly contributing to higher species diversity. Temporal variations in Simpson’s Diversity indices between grids were non‐significant except for three out of twenty‐one trapping sessions.