Mammals in a fragmented savannah landscape in south-western Brazil

Mammal abundance, richness, and community structure were examined in fragments of savannah and in gallery forests of south-western Brazil in order to assess the influence of fragment size and habitat on the communities. Five savannah fragments and two gallery forests were sampled. Within the savannah fragments, environmental parameters such as tree and shrub densities were measured. Live-traps and pitfalls were used for trapping small mammals; larger mammals were recorded from footprints and sightings. Seventeen species of small mammal and 15 species of large mammal were recorded. Small mammals were affected by fragment size and isolation, whereas larger mammals were not. Communities of small mammals were better structured in the largest fragments, and those in smaller fragments were subsets of the communities in larger fragments. Gallery forests revealed a rather different assemblage of mammals, but also contained species common to both gallery and large savannah remnants. Data are discussed relating mammal community structure to area size and vegetation structure, in an attempt to understand the present conservation status of this fragmented landscape.     

Temporal and spatial patterns of small mammal density and species composition on a radioactive waste disposal area: the role of edge habitat

Small mammal populations inhabiting radioactive waste disposal areas could be important vectors of contaminant redistribution, given sufficiently high numbers. Earlier studies conducted at the Subsurface Disposal Area (SDA) in southeastern Idaho found small mammal densities equaling or exceeding densities in native habitat. Our live-trapping study was conducted in 1988 and 1989 to assess the role of edge habitat (where SDA crested wheatgrass [ Agropyron cristatum ] plantings and native sagebrush habitat are separated by an earthen dike) in facilitating use of this highly modified site by small mammals. Small mammals had a significantly greater density in SDA edge habitat than in the interior. Total density of small mammals and immediately around the SDA appeared to be less variable over time than density in native sagebrush habitat for years when data were available. This phenomenon was largely attributable to steady or increasing SDA population densities of the most common species, Peromyscus maniculatus and Perognathus parvus , during 1988-89, when most small mammal species had below-average densities in surrounding areas. The variety of foraging options in edge habitat may have allowed these relatively opportunistic species to avoid widespread population declines associated with drought years in 1988-89. Movements by P. manicualtus across the boundary were common, suggesting that this species did indeed utilize both habitat types. Preferences for edge habitat could potentially be used to formulate strategies that reduce use of waste site by small mammals.     

Biogeographic significance of low-elevation records for Neotoma cinerea from the northern Bonneville Basin, Utah

The existence of low-elevation populations of Neotoma cinera in the northern Bonneville Basin shows either that these mammals can survive thousands of years in xeric habitats or that they can move across xeric lowlands far more readily than has been appreciated, or both. Current models of Great Basin small mammal biogeography are far too static to encompass properly the interaction of the wide range of geographical and biological variability that has produced the modern distribution of those mammals that have, for several decades, been treated as ""montane"" within the Great Basin.     

Did dinosaurs have any relation with dung‐beetles? (The origin of coprophagy)

It is widely accepted that Mesozoic ecosystems were basically similar to Cenozoic ecosystems and it has been proposed that the role of dung‐beetles in those ecosystems was identical to that of today, but the dung of dinosaurs were used as a source of food instead of the dung of mammals. While dinosaurs have been known since Triassic, Scarabeids are present in the fossil records probably since Lower Jurassic. But a very important metabolic feature of dinosaurs has not been taken into account, the connection between digestive and uro‐genital systems. So here we propose the hypothesis that coprophagy in dung‐beetles has been associated, since it began, with mammals.     

Type specimens of recent mammals in the Utah Museum of Natural History, University of Utah

A detailed list of holotypes of Recent mammals housed in the Utah Museum of Natural History is presented.     

Can hair width and scale pattern and direction of dorsal scapular mammalian hair be a relatively simple means to identify species?

Hair width and surface scale patterns (morphological characteristics) of hair from 21 selected species representing seven orders of mammals from the western United States were studied using scanning electron microscopy (SEM). The orders studied were Artiodactyla, Carnivora, Chiroptera, Didelphimorphia, Insectivora, Lagomorpha and Rodentia. Hair width, scale length and height, scale patterns, and scale position in relation to the shaft were used to characterize differences in morphology for both the species and orders. Specimens were taken from the dorsal scapular region and the centres of hair shafts of mature mammals were used for images. A key (identification chart) was created to characterize each species. These studies suggest that morphological differences in guard hair and underfur could provide a useful atlas for forensics, taxonomy and archaeology.     

Barn Owl (Tyto alba) prey in Evros (Greece) and the discovery of a new mammal for the Greek fauna

ABSTRACT

Small mammals are key elements of terrestrial ecosystems, yet in south-eastern Europe many questions about their taxonomy and distribution remain unanswered. This is particularly true for the small mammal fauna of Greece. We investigated the distribution of small mammals in the district of Evros (NE Greece) through Tyto alba pellet analysis and live-trapping in 19 localities (29 samplings). We collected remains from a total 2434 individual vertebrates through pellet analyses and captured 110 small mammals through live trapping. We provide data on the distribution and community composition in the corresponding localities, for 17 small mammal species (11 rodents and 6 insectivores). Our findings include the first record of Myomimus roachi in Greece, a result facilitated by the yearly dynamics of Microtus sp. populations, as well as the first record of Sorex minutus in Evros. The Barn owl’s main prey (by percentage, allocated to genera) were Crocidura (29.7%) Mus (27%) Microtus (23.2%) and Apodemus (13%).     

Distribution records and comments on mammals in western South Dakota

The mammal fauna of western South Dakota is imperfectly known; in particular there is a notable paucity of data from Indian reservations in the region. We collected mammals from January 2003 through May 2006 using a variety of standard methodologies, including trapping with snap-traps and Macabee traps, shooting, and salvaging road- and hunter-killed animals. Herein we provide 23 specimen-based county records representing 17 species of mammals. In addition, a photo record constitutes the first report of Dasypus novemcinctus from South Dakota and the northernmost record in the United States. The possible local extirpation of Marmota flaviventris in the southern Black Hills is discussed.     

Mites (excluding chiggers) of mammals of Oregon

New information on the ectoparasitic mites of the following species of mammals from Oregon is presented: (1) pika — Ochotona ; (2) squirrels — Eutamias, Spermophilus, Tamiasciurus; (3) grasshopper mouse — Onychomys; (4) woodrats — Neotoma; (5) muskrat — Ondatra; (6) jumping mice — Zapus; and (7) weasels — Mustela, Spilogale. New records of species for the state and new host records are also given. Finally, a cross - referenced list of all known mites of wild mammals from Oregon is presented.      

Insular biogeography of mammals in the Great Salt Lake

The distribution of 21 species of nonvolant mammals among nine islands in the Great Salt Lake was analyzed for biogeographic patterns. The number of species inhabiting an island is closely correlated with island area That the slope of the regression line describing this relationship (z or b) is relatively shallow compared to (1) totally isolated island systems or (2) island systems where an equilibrium between rates of colonization and extinction have been attained suggests that isolation plays little role in accounting for the variation in mammalian species diversity among islands. Stepwise multiple regression confirms this, while demonstrating that area alone accounts for 88 percent of the variation in species diversity among islands. However, endemic subspecies comprise a significant proportion of the insular mammalian fauna, suggesting that isolation for small mammals restricted to certain habitats may be substantial. A general scenario of the processes determining insular mammalian diversity and endemism is discussed for the Great Salt Lake, where the dynamic lake level creates a potential for different biogeographic processes over time.     

Diets of nesting Northern Goshawks in the Warner Mountains, California

Diets of Northern Goshawks ( Accipiter gentilis ) in western and eastern North America show regional differences. This variation may be explained by the opportunistic feeding behavior of Northern Goshawks and the greater number of potential prey species in western North America. We predicted that a population of Northern Goshawks in the Warner Mountains of California would take significantly more mammals than birds as prey. Goshawk diet in the Warner Mountains was determined by pellet analysis and prey remains. A total of 33 samples from 23 nest sites was collected and analyzed. Diets were quantified by determining the minimum number of individuals per sample at each nest site. As predicted, Warner Mountain Goshawks preyed more heavily on mammalian than avian prey species. Of the 221 individuals identified, 126 (57%) were mammals, while 95 (43%) were birds. These results are in accord with the suggestion that there are potentially more mammalian prey species in western North America than in eastern North America.     

A systematic revision of the genus Laelaps s. str. (Acari: Mesostigmata) of the Ethiopian region

This paper presents the results of a systematic study of mites of the genus Laelaps s. str. collected from small mammals of the Ethiopian region. Specimens taken from approximately 100,000 small mammals were examined from a wide variety of habitats and localities. The Ethiopian fauna of Laelaps mites includes 31 species. 4 of which are described as new: L. parasimillimus, L. myomys, L. malacomys, and L. acomys. A numerical taxonomic analysis was made, the results of which were used in the preparation of a proposed classification of the African species of Laelaps. A key for identification of females is given, and females and males (where known) of all species are illustrated. Diagnostic characters are given for the female and male of each species. Collection data and, where pertinent, discussions of morphological characters and variability are provided. Also included are discussions of host-parasite associations.     

Elevational zonation of birds,insectivores, rodents and primates on the slopes of the Andringitra Massif,Madagascar

A review is presented of the birds, lipotyphlans, rodents and lemurs occurring across an elevational transect from 720 to 2450 m within the 31160ha Parc National (PN) d'Andringitra in south-central Madagascar. The broad range of habitats within this reserve consists of lowland forest, montane forest, sclerophyllous forest, montane thicket, to open areas of bare rocks covered by geophytes. Eight different zones were surveyed across this elevational range for most of these four vertebrate orders. On the basis of these surveys and other sources of information, 106 species of birds, 16 species of Lipotyphla, 11 species of rodents (including two introduced species) and 13 species of primates are documented within the reserve. Surveys of the carnivores are incomplete, although eight species, three of which are introduced, have been recorded in the reserve. Forty-eight species of non-volant mammals are known from the Andringitra Massif, 43 of which are endemic to Madagascar. The highest species richness for birds was 85 species in the disturbed lowland forest at 720m zone and there was a subsequent reduction in the number of species at each site with increasing elevation. The two zones at 1210 and 1625 m with montane and mixed montane/sclerophyllous forest had the greatest species richness of non-volant mammals with 26 species (25 non-introduced). Lemurs showed decreasing species richness with increasing elevation. Small mammals showed broad elevational ranges and high species diversity in the middle to upper portion of the forest zone, with lipotyphlans peaking at 1990 m and rodents between 1625 and 1960 m. About 88 species of extant native rodents, carnivores, lipotyphlans and primates are currently recognized to occur on Madagascar. Thus, the PN d'Andringitra holds nearly 50% of the total known fauna of these groups from the island. This relatively small reserve plays a major role in safe-guarding a large proportion of the non-volant mammal fauna of Madagascar.     

Terrestrial vertabrates of Scotts Bluff National Monument, Nebraska

A survey of terrestrial vertebrates was conducted at the Scotts Bluff National Monument (SBNM), Nebraska, to determine species composition, relative abundance, and distribution by habitat of the existing amphibians, reptiles, birds, and mammals. Various sampling methods were used to detect animal species richness and to estimate population densities. The seven major habitat types at SBNM contained 4 species of amphibians, 8 reptiles, 96 birds, and 28 mammals. The only endangered or threatened species observed was a dead bald eagle ( Haliaeetus leucocephalus ). The racer ( Coluber constrictor ) and prairie rattlesnake ( Crotalus viridis ) were the two most abundant snakes. The prairie falcon ( Falco mexicanus ) was a common raptor that nested in Scotts Bluff. Sympatric populations of mule deer ( Odocoileus hemionus ) and white-tailed deer ( Odocoileus virginianus ) appeared to be hybridizing. The riverine woodland contained the greatest number of fauna species with only 4% surface area of SBNM. Sharp-tailed grouse ( Tympanuchus phasianellus ) and pronghorn antelope ( Antilocapra americana ), absent from the Monument, are two potential native species for reintroduction.     

Vegetative and edaphic factors affecting abundance and distribution of small mammals in southeast Oregon

The relationships between vegetative and edaphic habitat factors and the local distribution and abundance of small mammals on Malheur National Wildlife Refuge, Harney County, Oregon, were examined between July 1973 and June 1975. Of 16 species of small mammals captured, deer mice ( Peromyscus maniculatus ), montane voles ( Microtus montanus ), Great Basin pocket mice ( Perognathus parvus ), and least chipmunks ( Eutamias minimus ) comprised 90.1 percent of the individuals. The physiognomy of the vegetation was a factor in the distribution of rodent species other than deer mice. Pocket mice and chipmunks were restricted to the communities dominated by sagebrush ( Artemisia tridentata ) or greasewood ( Sarcobatus vermiculatus ). Population densities of pocket mice and chipmunks were significantly related to edaphic factors such as soil depth, texture, and strength, which may have affected the construction and stability of burrows. Montane voles occurred only in marsh or grassland communities. Population densities of voles were directly correlated with the amount of cover and inversely correlated with its patchiness. Deer mice were the most common species encountered and occurred in all but the grassland communities. The density of this species was related to vegetative or edaphic factors only seasonally or in certain habitats, and few generalizations could be made.     

Diet of pine martens Martes martes L. in west Scotland

Diet of pine martens in a coastal Atlantic oakwood in western Scotland was assessed over a period of two years (1996-8) in the context of strong potential competition from a diverse guild of other predators also largely dependent on preferred small rodent prey. Analysis of prey remains in fresh droppings showed that despite the potential for competition, martens still preyed extensively on small mammals and birds, preying preferentially on voles and particularly Microtus agrestis L. Invertebrates were also important dietary items, with high intake of beetles (and particularly Geotrupes sp.) from March to September. Predation on birds and intake of earthworms were highest over the winter period; fruits (bramble and rowan berries) were also important over the autumn and (ivy berries) late winter. The diet described is similar to that recorded in other studies, with no significant shifts due to potential competition from other predatory birds and mammals on the same species-poor prey base. However, marten activity in the area was subject to sudden seasonal decline in both sign and sightings and it seems possible that the animals may be making gross range shifts in periods of relative scarcity of high quality foods, moving substantial distances to track local availability of preferred prey.     

The relation between species numbers and island characteristics for habitat islands in a volcanic landscape

Within the Craters of the Moon Lava Flow in southeastern Idaho are kipukas, islands of sagebrush habitat isolated by relatively barren lava. In 1979 I counted the number of species of plants, small mammals, and reptiles for a series of kipukas. The degree of isolation of a kipuka was not related to numbers of species found there; thus, these data do not support the equilibrium theory of island biogeography. For most of the study organisms lava is not a significant barrier to dispersal. Larger kipukas support larger numbers of species. For plants this relationship likely is a result of the increased topographic variety of larger kipukas, whereas for small mammal species minimum area requirements for maintaining populations are met only by larger kipukas. More distant kipukas showed increased density of small mammals possibly as a result of reduced predation. Patterns of distribution in this ecosystem are best explained, not by any all-inclusive community mechanism, but through the agglomerative contributions of a variety of population and community functions.     

Deforestation affects biogeographical regionalization: a case study contrasting potential and extant distributions of Mexican terrestrial mammals

We used ecological niche modelling projected as species' potential (based on the original vegetation map) and extant (based on the 2000 land use and vegetation map) distributions to analyse changes on patterns of endemism of terrestrial mammals occurring in Mexico. Based on the biogeographic method of Parsimony Analysis of Endemicity, we obtained cladograms under scenarios of species' potential distribution (t1) and extant distributions (t2). We found that the resolution of consensus cladogram in t2 was poorer, while there were more geographic synapomorphies in t1, and more autapomorphies in t2 due to a reduction of species' distributions as a consequence of deforestation. We defined a hierarchical regionalization with two regions with the cladogram of t1; a transitional zone, two subregions, five dominions, and 15 provinces. Conversely, the consensus cladogram of t2 had a basal trichotomy, and the position of the Sierra Madre Occidental changed compared with t1. In t1 and t2, the Yucatán Peninsula+Chiapas+Isthmus of Tehuantepec clade was maintained, although in t2 it was separated from the remaining areas of the country. The impact of deforestation on species distributions strongly affected the biogeographic regionalization of terrestrial mammals in Mexico.     

Three additional cases of predation by magpies on small mammals

Three acts of predation by Black-billed Magpies ( Pica pica hudsonia ) on small mammals indicate that magpies will not only attack prey opportunistically encountered at close range, as suggested by recent literature, but will also pursue prey detected at long distances.         

Denning habitat and diet of the swift fox in western South Dakota

Swift fox ( Vulpes velox ) were investigated in western South Dakota to determine food habits and denning site characteristics. Over a three-year period food habits consisted of mammals (49%), followed by insects (27%), plants (13%), and birds (6%). Dens were located near hilltops within two habitat types, shortgrass and midgrass rairie; each type is characterized by differing plant species. Soil type was not a selective factor for den sites of swift fox. Management considerations for enhancing swift fox populations are presented.