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.     

Species composition,relative abundance and habitat association of small mammals along the altitudinal gradient of Jiren Mountain,Jimma, Ethiopia

To document the species composition, relative abundance and habitat association of small mammals, wet and dry season surveys were conducted along the altitudinal gradient of Jiren Mountain, Jimma area, Ethiopia. Sherman traps were used to capture small mammals from the six habitats: wetland, mixed plantation, open shrub, eucalyptus plantation, montane grassland and coffee plantation. The 393 trap nights, from the six habitat types, yielded 106 individual small mammals of tweleve species. The trapped rodents were Lophuromys flavopunctatus, Stenocephalemys albipes, Desmomys harringtoni, Mus mahomet, Lemniscomys barbarous, L. striatus, Tachyoryctes splendens, Mastomys natalensis and the insectivores Crocidura fumosa and C. turba. Two species of rodents Hystrix cristata and Helioscuirus gambianus were observed. Lophuromys flavopunctatus and S. albipes contributed 83.8% of the total capture. L. flavopunctatus, S. albipes and D. harringtoni were distributed in all habitats and gradients. T. splendens was captured from montane habitat, while the zebra mice were associated with the lower altitude habitats. Lophuromys flavopunctatus and M. natalensis extended their range deep into the coffee plantation habitats. Uncontrolled vegetation exploitation of the mountains for timber production and fire wood collection are the major threats. Conservation of the area to reduce the anthropogenic pressure is essential.     

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.     

Effects on bird abundance and species richness of edge restructuring to include shrubs at the interface between conifer plantations and moorland

Capsule?Bird species richness and (for most species) abundance were positively related to the extent of shrub cover at the interface between conifer plantations and moorland, but it appears that responses to shrub development vary between different bird guilds.

Aims?To assess the bird assemblages in both winter and breeding seasons at the interface between managed conifer plantations and open moorland, where that interface had been restructured to include a mosaic of shrubs and open ground.

Methods?Timed point counts were used to sample the birds at restructured plantation – moorland interface areas and also in neighbouring plantations (post- and pre-thicket age classes) and neighbouring moorland. Associations between species richness and abundances with measures of shrub cover and composition were assessed using GLMMs.

Results?A total of 60 bird species were recorded including 29 on lists of conservation concern, most of which were associated with shrub interface habitats. Species richness and, for most species, abundance were positively related to the extent of shrub cover. Positive relationships between shrub cover in interface areas and the abundance of some species in neighbouring plantations and open moorland suggested a resource subsidy to birds in neighbouring habitats. In contrast, some birds tended to be less abundant in plantations next to areas with more shrub cover. These species were more abundant in the shrub itself, suggesting redistribution by species with a preference for early successional shrub habitats.

Conclusions?The long-term management of shrub, especially with regard to successional development, is a challenging aspect of forest and landscape management that deserves further study.     

Habitat change and trade explain the bird assemblage from the La Chimba archaeological site in the northeastern Andes of Ecuador

The nature of tree‐line habitats in the Andes has long been a contentious topic in the ecological literature. Palynological studies suggest that a combination of anthropogenic and natural processes throughout the Holocene contributed to its present form and species composition. This is the first study to use zooarchaeological evidence to reconstruct possible prehistoric changes in these alpine habitats. I analysed the remains of birds from the La Chimba archaeological site in northern Ecuador to assess changes in the bird tree‐line community over three distinct phases (Early, 2640–2390 year BP; Middle, 2390–1994 year BP; Late, 1994–1700 year BP) of this prehistoric settlement. The elevation of this site (3200 m) places it near a steep elevational gradient in vegetation, with the modern tree‐line here at 3500–3600 m. Therefore, non‐local specimens of birds from the lowlands would hint at long‐distance trade. The composition of birds changes through time: species associated with high montane forest and shrubby páramos decrease and species from dry or open montane habitats increase. This trend is dominated by the decrease of Curve‐billed Tinamous Nothoprocta curvirostris (current elevational range 3000–3900 m) and a corresponding increase of specimens of Andean Tinamous Nothoprocta pentlandii (current elevational range 1000–2300 m). The large number of Andean Tinamous is surprising given that presently it occurs no closer than 300 km to the south of the La Chimba site. Overall, 18 of the 43 species of birds identified from La Chimba are likely to be the result of trade. This includes species from the eastern and western lowlands of Ecuador and one possible long‐distance transport from Peru. Prehistoric trade of birds and bird parts was probably common, and prehistoric anthropogenic landscape change and trade in birds should be considered as alternative explanations for species with disjunct populations in and across the Andes.     

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.     

Endemic gypsophytes composition delimitated by soil properties and altitude: From calciphytes to halophytes in the south–central Alborz Ranges

Specialized plant species have long served as geobotanical tools for locating mines and ores. Despite their importance, not much research has been dedicated to studying the ecology of endemic specialized plant species, such as those of gypsum or calcareous habitats. Here we describe and analyze the occurence of endemic plant species in gypsum habitats of the south–central Alborz Ranges (Semnan), Iran, in relation to altitude and soil properties. Ecological data and soil samples were collected from 120 plots along along an altitudinal gradient correlated with differences in soil properties. Forty seven plant species, including 6 species endemic to the Semnan area and 20 species endemic to Iran, were identified. The occurrence of the species were analyzed using canonical correspondence (CCA) and detrended correspondence Analysis (DCA), and based on the results the species were categorized as gypsophytes G₁ (1600–2245 m a.s.l.), calciphytes (1500–1700 m a.s.l.), gypsophytes G₂ (1300–1600 m a.s.l.) and halophytes (1100–1300 m a.s.l.). Gypsum content, elevation and salinity (Na content) were identified as the environmental factors having the largest effects on vegetation compositon. Endemic Semnan plant species included Astragalus fridae, Euphorbia gypsicola and Gypsophila mucronifolia at higher altitudes, and Astragalus semnanensis, Centaurea lachnopus and Nepeta eremokosmos at lower altitude gypsic soils. More frequent Iranian endemic plant species included Moltkia gypsaceae at higher altitudes, Echinops nizvanus and Acantholimon cymosum at lower altitude gypsic soils, Astragalus glaucacanthos, A. podolobus and A. microcephalus occurring mainly in calcic carbonate soil, and halophyte species such as Artemisia sieberi dominating at lower altitudes with more saline–alkaline soil.     

Community ecology of the terrestrial small mammals of Zakouma National Park,Chad

The terrestrial small mammal community of the Zakouma National Park (Chad) was assessed by live trapping in various habitats during the dry season. Nearly 3000 trap-nights yielded 505 captures of nine rodent and two shrew species, making up a representative small mammal community for the Sudanian savanna biotic zone. Murine rodents of the genusMastomys dominated, withM. erythroleucus andM. cf.kollmannspergeri occuring at similar abundances. The former was widespread and especially abundant in habitats with high tree cover. The latter was more localized, predominantly in annually flooded habitats characterized by a clay-rich soil, often withAcacia seyal as the main vegetation. Population structure differed between the two species, suggesting distinct reproductive strategies possibly linked with habitat preferences: theM. erythroleucus population comprised mainly young, immature individuals, whereasM. cf.kollmannspergeri was represented by older individuals, a significant fraction of which had already reproduced.Taterillus congicus andTatera kempi (gerbilline rodents), together withLemniscomys zebra, were mainly found in more open habitats with sand-rich soils.Arvicanthis niloticus, Acomys cf.johannis, Mus mattheyi andXerus erythropus were the other rodents captured, whereas shrews were represented byCrocidura fulvastra andSuncus sp.     

Genetic diversity of Lotus corniculatus in relation to habitat type,species composition and species diversity

The genetic variability of Lotus corniculatus, a common and important fodder legume, was studied in relation to habitat type and to species diversity at a local level. The study was conducted in Cholomontas mountain, northern Greece, at altitudes of 760–870 m. Genetic material was selected from four forested, at the edge of forest, and four open grassland sites, and was studied with the aid of ISSR molecular markers. The plant cover at each study site was measured and the floristic composition was estimated. The percentage of graminoides increased in grassland sites with high grazing intensity, while the abundance of legumes, including L. corniculatus, forbs and woody species, increased in forested sites with low grazing intensity. Gene diversity H_E within the studied populations of L. corniculatus ranged from 0.167 to 0.213 and Shannon index (I) from 0.269 to 0.340. Genetic differentiation was detected between habitats as well as among the populations in each habitat, although it was low, 3% and 7% respectively. However, genetic differentiation was significant within the populations (90%). Genetic diversity of L. corniculatus was not correlated with species diversity (richness and evenness) either within or between populations, while was negatively correlated with L. corniculatus abundance.     

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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How Does Chytrid Infection Vary Among Habitats? The Case of Litoria wilcoxii (Anura, Hylidae) in SE Queensland, Australia

Most analyses dealing with the geographical distribution of the chytrid fungus (Batrachochytrium dendrobatidis) have been performed on large geographical scales and data on more localized distribution of the chytrid within catchments are scarce. In this study, we compare the prevalence and intensity of infection of chytrid within and outside rainforest habitats at five independent catchments in southeast Queensland. In each catchment, we sampled adult Litoria wilcoxii along two transects on the same stream: one in forested areas, and the other in open nearby farmland. We analyzed swabs using quantitative PCR techniques. Male frogs were in higher densities in open habitats compared with the nearby forested areas. Infected male frogs were found in all catchments surveyed; however, prevalence of B. dendrobatidis in adult males was higher in the forested habitats than in the open habitats in four of the catchments. There was no significant difference in intensity of infection between forested and open habitats. For adult females and juveniles, sample sizes were not high enough for comparisons. Our results suggest that habitat influences chytrid prevalence and open areas may provide refuge from chytrid-induced population declines.     

Butterfly diversity and historical land cover change along an altitudinal gradient

Land cover and climate change are both major threats for biodiversity. In mountain ecosystems species have to adapt to fragmented habitats and harsh environmental conditions but so far, altitudinal effects in combination with land cover change have been rarely studied. The objective of this study was to determine the effects of altitude and historical land cover change on butterfly diversity. We studied species richness patterns of butterflies occuring in wetlands and other open habitats along an altitudinal gradient in a low mountain region (340–750 m a.s.l., Bavaria, Germany) with drastic loss of open habitats within the last 40–60 years. We recorded in 27 sites a total of 4,523 individuals of 49 butterfly species and five species of burnet moths. Species richness peaked at mid elevation and increased with patch size. Land cover change was most pronounced at high altitudes, but neither current open habitats, nor the historical loss of open habitats affected the species richness of butterflies. Neither open land specialized butterflies nor generalist and forest species were significantly affected by the loss of open habitats. However, increasing forest area in high altitudes reduces possible refuge open habitats for butterflies at their thermal distribution limits. This could lead to extinction of such butterfly species when temperatures further rise due to global warming.     

Comparison of soil seed banks of habitats distributed along an altitudinal gradient in northern Iran

In this study we investigated the variations in soil seed banks along an altitudinal gradient in the Alborz mountains, Iran, covering three habitats from lower to upper altitudes: forest, forest-subalpine grassland ecotone and subalpine meadow. In each habitat from 1850 to 2400 m, 20 quadrats were established along four transects, and the above-ground vegetation and the germinable seed banks were determined. Results show that the similarity between seed bank and vegetation was lowest in the ecotone located at intermediate altitudes. Together with the contrasting highest density and species diversity of seeds at these altitudes, the ecotonal role of this habitat was confirmed.We found evidence that lower altitudes could act as storage for seeds of some species growing at higher altitudes; the role of the ecotone was more prominent as a reserve for the meadow plant seeds than the role of the forest as a reserve for seeds of the meadow and ecotone habitats. Soil seed banks, particularly from the ecotone, can be used for restoring vegetation in some degraded sites.     

Response to cecropia cocoons of Mus musculus and two species of Peromyscus

Summary In rural areas cocoons of overwintering Hyalophora cecropia spum close to the ground are opened and the pupae eaten by small mammals, but in urban areas, where cecropia populations are much larger, the cocoons are almost never opened by mammals. Peromyscus leucopus noveboracensis and P. maniculatus bairdii are abundant in rural areas, but are largely replaced by Mus musculus in urban areas. In laboratory experiments P. l. noveboracensis invariably opened cecropia cocoons and ate the pupae. P. m. bairdii were slower to open cecropia cocoons and two of twelve did not open one at all. M. musculus, on the other hand, never opened cecropia cocoons although they gnawed the silk and ate uncovered pupae. Cocoons opened in the laboratory by the two species of Peromyscus cannot be distinguished from each other or from cocoons opened in the field.Part of the Ph. D. dissertation presented by the first author to the Department of Entomology, University of Illinois. This investigation was supported in part by PHS Training Grant no. 2-T01-GM 01076 from General Medical Sciences.     

Diversity,dynamics and reproduction in a community of small mammals in Upper Guinea,with emphasis on pygmy mice ecology

As part of a large survey on reservoirs of Lassa fever in Guinea, three villages were investigated in high endemic zone, close to Sierra Leone border. Biodiversity of the small mammal community is presented in this study through a standardized trapping in houses, cultivations and forest. Identification of the small mammals was based on morphology and by molecular technique for sibling species. Of the 1123 specimens collected in 2003–2005, we identified seventeen species (thirteen Muridae, four Soricidae), leading to high diversity (Shannon index = 1.6–1.8) and high equitability (evenness index = 0.7–0.8) in cultivations and forest. In houses conversely, the rodent community was dominated by Mastomys natalensis (95–98%), leading to low diversity and equitability. Dynamics and reproduction were investigated in two species of pygmy mice, Mus mattheyi and Mus minutoides, two species of Praomys, P. daltoni and P. rostratus, and in Mastomys erythroleucus. The pygmy mice were abundant in cultivations in early rainy season, and reproduced from rainy to dry season. Praomys daltoni was also found more abundant in cultivations and seemed to reproduce between rainy and dry season, whereas P. rostratus preferred forest and cultivations in late rainy season, and reproduced throughout the year. Finally, M. erythroleucus was more abundant in forest in dry season, and seemed to reproduce from late rainy to dry season. This species had a low occurrence (6.5%) in the Faranah’s zone, and probably lived at its southern limit in Guinea. The presence of other Murinae, such as M. natalensis, Praomys spp as possible competitors in the same habitats, is discussed. For the first time, this study relates population biology of pygmy mice with molecular identification.     

Metals and altitude drive genetic diversity of chironomids in Andean streams

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Ecology of the pteridophytes on the southern slopes of Mt. Kilimanjaro – I. Altitudinal distribution

140 taxa of 61 genera in 24 families of pteridophytes were recorded on the southern slopes of Mt. Kilimanjaro. These represent about one third of the entire pteridophyte flora of Tanzania. The families richest in species are the Aspleniaceae, the Adiantaceae, the Dryopteridaceae, the Thelypteridaceae and the Hymenophyllaceae. Due to its luxuriant montane rain forest, which receives a precipitation of up to over 3000 mm, Mt. Kilimanjaro is distinctly richer in pteridophyte species than other volcanoes in East Africa. However, compared with the mountains of the Eastern Arc, the number of pteridophytes on Mt. Kilimanjaro is smaller. This can be explained by the widely destroyed submontane (intermediate) forest rather than by the higher age of the Eastern Arc Mts.The altitudinal distribution of all ferns was investigated in 24 transects. On the southern slopes of Mt. Kilimanjaro they were found in an altitudinal range of 3640 m. Cyclosorus quadrangularis, Azolla nilotica, Azolla africana andMarsilea minuta are restricted to the foothills, while Polystichum wilsonii, Cystopteris nivalis and Asplenium adiantum-nigrum are species found in the highest altitudes.Based on unidimensionally constrained clustering and on the analysis of the lowermost and uppermost occurrence of species, floristic discontinuities within the transects were determined. From these data and from an evaluation of the distribution of ecological groups and life forms, 11 altitudinal zones could be distinguished: a colline zone (–900 m asl), a submontane zone (900–1600 m asl) with lower and upper subzones, a montane zone (1600-2800 m asl) divided into 4 subzones, a subalpine zone (2800–3900 m asl) with lower, middle and upper subzones, and finally a (lower) alpine zone above 3900 m. The highest species numbers were observed in the lower montane forest belt between 1600 and 2000 m altitude. The zonation of ferns found at Mt. Kilimanjaro corresponds well with the vegetational zonation described by other authors using bryophytes as indicators in different parts of the humid tropics.     

Floristic altitudinal zones in Malesia

From the altitudinal ranges of species recorded for the Malesian mountain flora, in Flora of Java and the 6 or so volumes of Flora Malesiana it was concluded that there are critical altitudes where the floristic composition shows rather abrupt demarcations, namely at 1000, 1500, 2400 and 4000 m altitude. In a generalized way this also holds for the structure and stature of the vegetation. For cultivated plants the altitudes of 1000 and 1500 m are also distinct demarcations.     

Composition and diversity of bird communities in Swedish farmland–forest mosaic landscapes

CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.     

The lichen genus Umbilicaria in Ecuador

Nine species of the saxicolous lichen genus Umbilicaria from Ecuador are reported and a key is provided: U. africana, U. aprina, U. cinereorufescens, U. decussata, U. dendrophora, U. haplocarpa, U. leprosa, U. nylanderiana and U. vellea. The species diversity of this genus on the equatorial high mountains of South America is low compared to North America and Eurasia, but similar to that found on high African peaks close to the equator. The species mostly belong to a high‐alpine element with worldwide distribution. Two species belong to an Andean endemic element, viz U. haplocarpa and U. leprosa. The low diversity and low percentage of endemism may reflect the fairly recent uplift of the Andes and the comparatively small geographic extent of the alpine Andean biota. The dense rainforests of Ecuador leave few suitable open rock habitats for the establishment of these light‐craving lichens below the tree‐line (4000–4200 m a.s.l.), and thus their equatorial habitat is almost exclusively restricted to the alpine zone between the tree‐line and the snow‐line (4700–4800 m a.s.l.). The equatorial species mainly reproduce asexually by thalloconidia, and the adaptive significance of this type of reproduction in high altitude habitats is discussed.