Changes in aboveground locomotion of a scansorial opossum associated to habitat fragmentation

2020 ◽  
Vol 101 (4) ◽  
pp. 1097-1107
Author(s):  
Ana Cláudia Delciellos ◽  
Suzy Emidio Ribeiro ◽  
Jayme Augusto Prevedello ◽  
Marcus Vinícius Vieira
Keyword(s):  
Habitat Fragmentation ◽  
Animal Movement ◽  
Interspecific Interactions ◽  
Home Ranges ◽  
Forest Fragments ◽  
Active Selection ◽  
Continuous Forest ◽  
Forest Sites ◽  
Males And Females ◽  
Selection Of

Abstract Habitat fragmentation may affect animal movement patterns due to changes in intra- and interspecific interactions as well as in habitat quality and structure. Although the effects of habitat fragmentation on terrestrial movements are relatively well-known, it is unclear whether and how they affect aboveground locomotion of individuals. We compared aboveground locomotion of a Neotropical small mammal, the gray four-eyed opossum, Philander quica, between two forest fragments and two areas of continuous forest in the Brazilian Atlantic Forest. We 1) quantified support availability and tested for active selection of different support diameters and inclinations by individuals; and 2) compared support diameters and inclinations used (observed values) among areas and between males and females. Both males and females selected supports based on diameters and inclinations in forest fragments. In continuous forests sites, females selected supports based on diameters and inclinations, but males selected only support diameters. Frequency of support diameter use differed significantly between forest fragments and continuous forest sites and between males and females. Frequency of support inclination use differed significantly between areas only for females, and between sexes only in continuous forest sites. Sex-related differences in support selection and use are likely related to differences in body size and conflicting energetic and behavioral demands related to use of arboreal space. Site-related differences in aboveground movements likely reflect the effects of forest edges that result in increased use of thinner supports in forest fragments. These results complement our previous findings that habitat fragmentation reduces daily home ranges and increases the total amount of aboveground locomotion of P. quica, and provide a more thorough picture of how forest-dependent species are able to use and persist in small forest fragments.

scholarly journals Species-Area Relationships Induced by Forest Habitat Fragmentation Apply Even to Rarely Detected Organisms

2021 ◽  
Vol 14 ◽  
pp. 194008292110173
Author(s):  
Ana Filipa Palmeirim ◽  
Rafael de Fraga ◽  
Marcus V. Vieira ◽  
Carlos A. Peres
Keyword(s):  
Biodiversity Loss ◽  
Forest Fragments ◽  
Detection Rates ◽  
Conservation Policies ◽  
Number Of Species ◽  
Continuous Forest ◽  
Forest Sites ◽  
Species Area ◽  
Riparian Habitats ◽  
Forest Islands

Neotropical snakes have extremely low detection rates, hampering our understanding of their responses to habitat loss and fragmentation. We addressed this gap using a limited sample (50 individuals, 16 species) across 25 variable-size insular forest fragments within a hydroelectric lake and four adjacent mainland continuous forest sites, in Central Brazilian Amazonia. The number of species recorded on forest islands (1.55 [Formula: see text] 0.78) was much lower than that at continuous forest sites (5.0 [Formula: see text] 3.1), with no snakes being recorded at twelve islands smaller than 30 ha. As such, snake assemblages were positively affected by forest area, explaining 48% of the number of species, and negatively affected by island isolation. The markedly higher number of species recorded across continuous forest sites likely results from the availability of riparian habitats, which have virtually disappeared from the archipelagic landscape given the widespread inundation of lowland areas. To prevent further severe biodiversity loss, including those of poorly known rare taxa, conservation policies should avert the additional construction of mega-dams that create myriad of small islands, in addition to extensive reservoir lakes from which all riparian habitats are eliminated.

Home range and habitat use by Lumholtz’s tree-kangaroo (Dendrolagus lumholtzi) within a rainforest fragment in north Queensland

1999 ◽  
Vol 26 (2) ◽  
pp. 129 ◽  
Author(s):  
Graeme R. Newell
Keyword(s):  
Home Range ◽  
Social Interactions ◽  
Home Range Size ◽  
Tropical Rainforests ◽  
Home Ranges ◽  
Forest Fragments ◽  
Wide Range ◽  
Adult Tree ◽  
Males And Females ◽  
Dendrolagus Lumholtzi

Lumholtz’s tree-kangaroo (Dendrolagus lumholtzi), one the largest arboreal mammals in Australia, has been poorly studied owing to its limited distributional range and secretive habits within tropical rainforests. This study investigated the way D. lumholtzi used its habitat within a rainforest fragment on the Atherton Tableland, North Queensland. Thirteen animals were fitted with radio-collars to determine their spatial and temporal use of habitat. Female D. lumholtzi used exclusive home ranges averaging 0.7 ha in area (90% harmonic mean), while males occupied larger home ranges of an average of approximately 2 ha, allowing for a density of 1.4–1.5 adult tree-kangaroos per hectare within the study area. The exception to this home- range size was one juvenile male presumably undergoing post-natal dispersal that used several forest fragments and other habitats, with a home range of 332 ha. Home ranges of males overlapped in part the ranges of several females. Home ranges of males tended to abut those of other males, and antagonistic encounters occurred at the boundaries of the home ranges. Males had a significantly larger body size than females (males 8.63 kg; females 7.05 kg). Social interactions between individuals, apart from antagonistic male–male encounters, were observed infrequently. Only 6% and 2.7% of fixes for females and males, respectively, included the presence of another animal in the same or adjacent tree at the time of location. Lumholtz’s tree-kangaroos were associated with a wide range of rainforest trees and a smaller number of vine species. However, in general, individual animals regularly associated with only a small suite (mean 3.5 species with >10% usage) of tree species present within their home range, and appeared to display individual preferences for certain species. Individual radio-tracked D. lumholtzi were visible only 9.4% of the time at night, and 20% of the time during the day. Males and females were as visible as each other, and both were seen significantly lower in the canopy and into the mid-storey during the night than during the day.

scholarly journals Diet and prey availability of terrestrial insectivorous birds prone to extinction in amazonian forest fragments

2010 ◽  
Vol 53 (6) ◽  
pp. 1371-1381 ◽  
Author(s):  
Luiz Augusto Macedo Mestre ◽  
Mario Cohn-Haft ◽  
Manoel Martins Dias
Keyword(s):  
Prey Size ◽  
Prey Availability ◽  
Bird Species ◽  
Sympatric Species ◽  
Territory Size ◽  
Forest Fragments ◽  
Insectivorous Birds ◽  
Continuous Forest ◽  
Forest Sites ◽  
Diet Variability

This study compared niche breath, prey size, and diet variability in two pairs of sympatric species of terrestrial insectivorous birds, each pair containing one species that can persist in small forest fragments and one that does not. The pairs were Myrmeciza ferruginea and Sclerurus rufigularis; and Formicarius colma and F. analis, respectively. The prey availability in forest fragments was also sampled and compared to the availability in continuous forests. Niche breath indices did not differ between pair members, but diet variability differed in the opposite direction from that hypothesized. Although the two bird species most vulnerable to fragmentation fed on larger prey than less vulnerable species, prey availability, including that based on prey size did not differ among fragmented versus continuous forest sites. Thus, diet per se appeared not to be an important cause of extinction-proneness in these species. The simplest explanation proposed, that vulnerability to fragmentation was directly related to territory size, requires testing. However, it was consistent with observations that the bird species feeding on larger prey also need larger territories.

Habitat fragmentation and haemoparasites in the common fruit bat, Artibeus jamaicensis (Phyllostomidae) in a tropical lowland forest in Panamá

Parasitology ◽  
2009 ◽  
Vol 136 (10) ◽  
pp. 1133-1145 ◽  
Author(s):  
V. M. COTTONTAIL ◽  
N. WELLINGHAUSEN ◽  
E. K. V. KALKO
Keyword(s):  
Habitat Fragmentation ◽  
Special Focus ◽  
Forest Fragments ◽  
Lowland Forest ◽  
Tropical Lowland ◽  
Fruit Bat ◽  
Artibeus Jamaicensis ◽  
Continuous Forest ◽  
Tropical Lowland Forest ◽  
The Common

SUMMARYAnthropogenic influence on ecosystems, such as habitat fragmentation, impacts species diversity and interactions. There is growing evidence that degradation of habitats favours disease and hence affects ecosystem health. The prevalence of haemoparasites in the Common Fruit Bat (Artibeus jamaicensis) in a tropical lowland forest in Panamá was studied. We assessed the relation of haemoparasite to the general condition of the animals and tested for possible association of haemoparasite prevalence to habitat fragmentation, with special focus on trypanosomes. Overall, a total of 250 A. jamaicensis sampled from fragmented sites, here man-made, forested islands in Lake Gatùn, and sites in the adjacent, continuous forest in and around the Barro Colorado Nature Monument were examined. Using microscopy and DNA-sequencing 2 dominant types of haemoparasite infections, trypanosomes and Litomosoides (Nematoda) were identified. Trypanosome prevalence was significantly higher in bats from forest fragments, than in bats captured in continuous forest. We attribute this to the loss of species richness in forest fragments and specific characteristics of the fragments favouring trypanosome transmission, in particular changes in vegetation cover. Interestingly, the effect of habitat fragmentation on the prevalence of trypanosomes as multi-host parasites could not be observed in Litomosoides which probably has a higher host specificity and might be affected less by overall diversity loss.

scholarly journals Phytosociological contrast of ferns and lycophytes from forest fragments with different surroundings matrices in southern Brazil

2019 ◽  
Vol 79 (3) ◽  
pp. 495-504
Author(s):  
V. L. Silva ◽  
I. T. Mallmann ◽  
V. Graeff ◽  
J. L. Schmitt ◽  
K. Mehltreter
Keyword(s):  
Forest Fragments ◽  
Natural Field ◽  
Araucaria Forest ◽  
Forest Sites ◽  
Different Types ◽  
The Matrix ◽  
Selection Of Species ◽  
Understory Communities ◽  
Ferns And Lycophytes ◽  
Selection Of

Abstract Forest edges typically exhibit higher luminosity and lower humidity than the forest interior, resulting in an abiotic gradient. However, the degree of abiotic difference can be affected from the type of the matrix, influencing the selection of species. We compared the floristic and phytosociological structure of understory communities of ferns and lycophytes of the edge and interior of three forest sites influenced by different types of surrounding matrices (natural field, Pinus plantation, and cultivation of crops). In the region of Araucaria Forest, in Rio Grande do Sul, Brazil, twelve 10 × 10 m plots were selected at the edge and interior of each site, totaling 72 plots and to evaluate the phytosociological contrast, using as a parameter coverage and species richness per plot to evaluate this contrast. We recorded a total of 38 species in the studied areas, distributed in 15 families. The results show that the edge effect acts at different intensities in the analyzed sites. In the site with unnatural matrix, the composition was more homogeneous both in the edges and in the interiors and presented lower richness, showing a more pronounced and deep impact. Already in the site with natural matrix surroundings, although the border also presents low richness, the interior was about 3x richer. Based on our results, we concluded that fern conservation efforts should focus on fragments of Araucaria Forest inserted in the natural field, because the conversion of natural field into Pinus planting and cultivation of crops decreases ferns species both in the edges and forest interiors of the studied fragments, besides altering the phytosociological structure leading the communities to simplification.

Diagnostic approach to causes of spinal pain

2018 ◽  
pp. 66-70
Author(s):  
F. D. Nasirova
Keyword(s):  
Spinal Pain ◽  
Rapid Loss ◽  
Loss Of Weight ◽  
History Of ◽  
Radiologic Investigation ◽  
Males And Females ◽  
Serious Disease ◽  
Pain At Rest ◽  
Oncologic Diseases ◽  
Selection Of

Causes of spinal pain are extremely varying. Sex composition of patients referring with spinal pain at the age of 16 to 35 was 35% and 65% for males and females, respectively. Peak number of complaints was observed in 30-40 years age group of highest work ability. The followings should be considered as precautions in spinal pain: onset of pain at the age of 20 and after 50, family history of oncologic diseases, walking disorders or dysfunctions of sphincters, numbness in extremities, general malaise and rapid loss of weight, pain at rest and primarily at night, as these conditions may be a warning of underlying serious disease. Selection of algorithm for radiologic investigation is decided by the treating physician.

scholarly journals Changes in surface water drive the movements of Shoebills

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marta Acácio ◽  
Ralf H. E. Mullers ◽  
Aldina M. A. Franco ◽  
Frank J. Willems ◽  
Arjun Amar
Keyword(s):  
Surface Water ◽  
Optimal Foraging ◽  
Animal Movement ◽  
Bird Species ◽  
Individual Variability ◽  
Home Ranges ◽  
Age Classes ◽  
Water Index ◽  
Normalized Difference Water Index ◽  
Conservation Actions

AbstractAnimal movement is mainly determined by spatial and temporal changes in resource availability. For wetland specialists, the seasonal availability of surface water may be a major determinant of their movement patterns. This study is the first to examine the movements of Shoebills (Balaeniceps rex), an iconic and vulnerable bird species. Using GPS transmitters deployed on six immature and one adult Shoebills over a 5-year period, during which four immatures matured into adults, we analyse their home ranges and distances moved in the Bangweulu Wetlands, Zambia. We relate their movements at the start of the rainy season (October to December) to changes in Normalized Difference Water Index (NDWI), a proxy for surface water. We show that Shoebills stay in the Bangweulu Wetlands all year round, moving less than 3 km per day on 81% of days. However, average annual home ranges were large, with high individual variability, but were similar between age classes. Immature and adult Shoebills responded differently to changes in surface water; sites that adults abandoned became drier, while sites abandoned by immatures became wetter. However, there were no differences in NDWI of areas used by Shoebills before abandonment and newly selected sites, suggesting that Shoebills select areas with similar surface water. We hypothesise that the different responses to changes in surface water by immature and adult Shoebills are related to age-specific optimal foraging conditions and fishing techniques. Our study highlights the need to understand the movements of Shoebills throughout their life cycle to design successful conservation actions for this emblematic, yet poorly known, species.

scholarly journals A Clinical Study to Correlate the Facial Form and Maxillary Central Incisor Tooth Form in Males and Females of Davangere Population

2016 ◽  
Vol 04 (03) ◽  
pp. 156-164
Author(s):  
Deepak Bansal ◽  
Shruti Sharma ◽  
Manjit Kumar ◽  
Amrit Khosla
Keyword(s):  
Facial Appearance ◽  
Central Incisor ◽  
Incisor Tooth ◽  
Maxillary Central Incisor ◽  
Anterior Teeth ◽  
The Face ◽  
Tooth Form ◽  
Males And Females ◽  
Selection Of ◽  
Made In

AbstractAn altered facial appearance is more difficult to face, than problems related to ill-fitting denture or eating. The selection of maxillary anterior teeth for complete denture has long posed problem in clinical practice and a controversy about the best method to employ still exists. An attempt is made in the present study to clinically correlate the face form with maxillary central incisor tooth form in males and females of Davangere population. In 1914, Leon William's projected the “the form method” where he classified facial forms as square, tapering, and ovoid. Maxillary central incisors were selected according to the facial forms.Of total 100 subjects four different tooth forms and face forms were evaluated. They are: square, ovoid, square-tapered, tapered. No significant correlation existed between face form in male and females. Females exhibited greater correlation between face forms and inverted tooth form but that correlation is not sufficient to serve as a guide for selection of anterior teeth.

Spacing, movements, and habitat selection of the river otter in boreal Alberta

1994 ◽  
Vol 72 (7) ◽  
pp. 1314-1324 ◽  
Author(s):  
D. G. Reid ◽  
T. E. Code ◽  
A. C. H. Reid ◽  
S. M. Herrero
Keyword(s):  
Lontra Canadensis ◽  
Home Ranges ◽  
Adult Males ◽  
Movement Rates ◽  
River Otters ◽  
Aquatic Mammal ◽  
Adult Females ◽  
Two Factors ◽  
Bog Lakes ◽  
Selection Of

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.

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