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The ecology and conservation of insectivorous bats in rural landscapesLumsden, Linda F, mikewood@deakin.edu.au January 2004 (has links)
Throughout the world, the increasing use of land for agriculture has been associated with extensive loss and fragmentation of natural habitats and, frequently, the degradation of remaining habitats. The effects of such habitat changes have been well studied for some faunal groups, but little is known of their consequences for bats. The aim of this study was to investigate the ecology and conservation of an assemblage of insectivorous bats in a rural landscape, with particular focus on their foraging and roosting requirements. This increased knowledge will, hopefully, assist the formulation of policy and management decisions to ensure the long-term survival of bats in these altered environments.
The distribution and abundance of insectivorous bats in the Northern Plains of Victoria was investigated to determine the impacts of land-use change and to identify factors influencing the distribution of bats in rural landscapes. Thirteen species of insectivorous bats were recorded across the region by sampling at 184 sites. Two species were rare, but the remaining 11 species were widespread and occurred in all types of remnant wooded vegetation, ranging from large blocks (≥200 ha) to small isolated remnants (≤5 ha) and scattered trees in cleared farm paddocks. There was no significant difference between remnant types in the relative abundance of bat species, in species richness, or in the composition of bat assemblages at study sites. In a subsequent study, no difference in the activity levels of bats was found between remnants with different tree densities, ranging from densely-vegetated blocks to single paddock trees. However, sites in open paddocks devoid of trees differed significantly from all types of wooded remnants and had significantly lower levels of bat activity and a different species composition. In highly cleared and modified landscapes, all native vegetation has value to bats, even the smallest remnant, roadside and single paddock tree.
Roost sites are a key habitat requirement for bats and may be a limiting resource in highly modified environments. Two species, the lesser long-eared bat Nyctophilus geoffroyi and Gould's wattled bat Chalinolobus gouldii, were investigated as a basis for understanding the capacity of bats to survive in agricultural landscapes. These species have different wing morphologies, which may be influential in how they use the landscape, and anecdotal evidence suggested differences in their roosting ecology.
Roosting ecology was examined using radio-tracking to locate 376 roosts in two study areas with contrasting tree cover in northern Victoria. Both species were highly selective in the location of their roosts in the landscape, in roost-site selection and in roosting behaviour, and responded differently to differing levels of availability of roosts.
The Barmah-Picola study area incorporated remnant vegetation in farmland and an adjacent extensive floodplain forest (Barmah forest). Male N. geojfroyi roosted predominantly within 3 km of their foraging areas in remnants in farmland. However, most female N. geoffroyi, and both sexes of C. gouldii, roosted in Barmah forest up to 12 km from their foraging areas in farmland remnants. These distances were greater than previously recorded for these species and further than predicted by wing morphology. In contrast, in the second study area (Naring) where only small remnants of wooded vegetation remain in farmland, individuals of both species moved significantly shorter distances between roost sites and foraging areas.
There were marked inter- and intra-specific differences in the roosts selected. C. gouldii used similar types of roosts in both areas - predominantly dead spouts in large, live trees. N. geoffroyi used a broader range of roost types, especially in the farmland environment. Roosts were typically under bark and in fissures, with males in particular also using anthropogenic structures. A strong preference was shown by both sexes for roosts in dead trees, and entrance dimensions of roosts were consistently narrow (2.5 cm). In Barmah forest, maternity roosts used by N. geoffroyi were predominantly in narrow fissures in large-diameter, dead trees, while at Naring maternity roosts were also found under bark, in buildings, and in small-diameter, live and dead trees.
The number of roost trees that are required for an individual or colony is influenced by the frequency with which bats move between roosts, the proportion of roosts that are re-used, the distance between consecutive roosts, and the size of roosting colonies. Both species roosted in small colonies and regularly shifted roost sites within a discrete roost area. These behavioural traits suggest that a high density of roost sites is required. There were marked differences in these aspects of behaviour between individuals roosting in Barmah forest and in the fragmented rural landscape. At
Naring, N. geqffroyi remained in roosts for longer periods and moved greater distances between consecutive roosts than in Barmah forest. In contrast, C. gouldii used a smaller pool of roosts in the farmland environment by re-using roosts more frequently. Within Barmah forest, there is an extensive area of forest but the density of hollow-bearing trees is reduced due to timber harvesting and silvicultural practices. Individuals were selective in the location of their roosting areas, with both species selecting parts of the forest that contained higher densities of their preferred roost trees than was generally available in the forest. In contrast, in farmland at Naring, where there were small pockets of remnant vegetation with high densities of potential roost sites surrounded by cleared paddocks with few roosting opportunities, little selection was shown. This suggests that in Barmah forest the density of trees with potential roosts is lower than optimal, while in farmland roosting resources may be adequate in woodland remnants, but limiting at the landscape scale since more than 95% of the landscape now provides no roosting opportunities.
Insectivorous bats appear to be less severely affected than some other faunal groups by habitat fragmentation and land-use change. A highly developed capacity for flight, the spatial scale at which they move and their ability to cross open areas means that they can regularly move among multiple landscape elements, rather than depend on single remnants for all their resources. In addition, bats forage and roost mainly at elevated levels in trees and so are less sensitive to degradation of wooded habitats at ground level. Although seemingly resilient to habitat fragmentation, insectivorous bats are fundamentally dependent on trees for roosting and foraging, and so are vulnerable to habitat loss and ongoing rural tree decline. Protection of the remaining large old trees and measures to ensure regeneration to provide ongoing replacement of hollow-bearing trees through time are critical to ensure the long-term conservation of bats in rural landscapes.
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The potential of using insectivorous bats (Microchiroptera) as a means of insect pest control in agricultural areasMarais, Werner Christiaan 03 June 2010 (has links)
M.Sc. / Members of the Suborder Microchiroptera consume large numbers of insects. When large enough numbers of these bats are present in agricultural areas, the need for insecticides can be reduced significantly. The ZZ2 Tomato Farms in Mooketsi and the Secrabje Farm in Waterpoort, in the Limpopo Province were chosen as study sites. Although ZZ2 focuses on the production of tomatoes, both farms produce a variety of vegetables and fruit. These farms were chosen because the management of both have shown a commitment to conservation and attempt to minimise their impact on the environment. Bat species indigenous to the study areas were captured by means of mist nets for identification purposes. Basic morphological data of captured specimens were collected and recorded. Their roosting behaviour and preferences were studied by visiting diurnal roosts in the two study sites. Microclimatic measurements were taken in roosts occupied by Chaerephon pumilus, Mops condylurus and Taedarida aegyptiaca. Microclimatic measurements were also done in bat houses designed for the housing of bats in agricultural areas. Results suggest that other factors, additional to temperature and relative humidity, contribute to the success and probability of bat house occupancy by bats. Existing roosts in man-made structures such as roofs, can successfully be enhanced to stimulate increase in colony size. Bat activities were determined in agricultural areas and adjacent natural habitats by means of recordings of the echolocation calls of the different bat Families. These were compared to the occurrence of nocturnal flying insect orders that were captured in light traps at the same localities. Of the bat species studied, a positive correlation between increased bat activity and higher number of insects, including pest species, was found. It seems as if the Molossidae has the greatest potential to be utilised in the control of insect pests of agricultural areas in the Limpopo of the bat species studied. A holistic approach favouring insectivorous bats on farms is recommended. This can be done i.a. through the conservation of abundant areas of natural vegetation adjacent to the agricultural areas which would provide foraging for bats during winter, periods of drought or when the lands lie fallow. The excessive and injudicious use of insecticides, which has a negative effect on bats, counteracts the beneficial and cheap alternative of natural insect pest control provided by insectivorous bats.
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The Ecology and Conservation of the White-Striped Freetail Bat (Tadarida australis) in Urban EnvironmentsRhodes, Monika, n/a January 2006 (has links)
Of all anthropogenic pressures, urbanisation is one of the most damaging, and is expanding in its influence throughout the world. In Australia, 90% of the human population live in urban centres along the eastern seaboard. Before European settlement in the early 1800s, much of the Australia's East coast was dominated by forests. Many of the forest dependent fauna have had to adapt to forest fragmentation and habitat loss resulting from clearing for urbanisation. However, relatively few studies have investigated the impact of urbanisation on biodiversity. This is especially true for the remaining fauna in large metropolitan areas, such as Melbourne, Sydney and Brisbane. The physical and conceptual context of this thesis is the increasing impact of urbanisation and the potentially threatening factors to forest dependent fauna. Bats were selected because they comprise a third of Australia's mammal species, and therefore form a major component of Australia's biodiversity. Very little is known about the ecology and conservation biology of hollow-dependent bats in general, but particularly in urban environments. The study was conducted in Brisbane, south-east Queensland, one of Australia's most biodiverse regions. More than a third of Australia's bat species occur in this region. A large insectivorous bat, the white-striped freetail bat (Tadarida australis), was selected to study two key resources in this urban area - hollow availability and foraging habitat. This thesis also examined if artificial roost habitat could provide temporary roosts for white-striped freetail bats and other insectivorous bats and assessed whether these bat boxes can be used as a conservation tool in urban environments where natural hollow-availability is limited. The white-striped freetail bat is an obligate hollow-dweller and roosted largely in hollows of old or dead eucalypts throughout Brisbane's urban matrix. These roost trees harboured significantly more additional hollow-dependent species compared to control trees of similar age, height, and tree diameter. Roost cavities inside trees often exceeded 30 cm in diameter. Furthermore, maternity colonies used cavities of hollow trunks, which often extended into major branches, to roost in big numbers. Therefore artificial alternatives, such as small bat boxes, may provide temporary shelter for small roosting groups, but are unlikely to be suitable substitutes for habitat loss. Although five bat species used bat boxes during this study, the white-striped freetail bat was not attracted into bat boxes. Roost-switching behaviour was then used to quantify associations between individual white-striped freetail bats of a roosting group. Despite differences in gender and reproductive seasons, the bats exhibited the same behaviour throughout three radio-telemetry periods and over 500 bat-days of radio-tracking: each roosted in separate roosts, switched roosts very infrequently, and associated with other tagged bats only at a communal roost. Furthermore, the communal roost exhibited a hub of socialising between members of the roosting group especially at night, with vocalisation and swarming behaviour not found at any of the other roosts. Despite being spread over a large geographic area (up to 200 km2), each roost was connected to others by less than three links. One roost (the communal roost) defined the architecture of the network because it had the most links. That the network showed scale-free properties has profound implications for the management of the habitat trees of this roosting group. Scale-free networks provide high tolerance against stochastic events such as random roost removals, but are susceptible to the selective removal of hub nodes, such as the communal roost. The white-striped freetail bat flew at high speed and covered large distances in search for food. It foraged over all land-cover types found in Brisbane. However, its observed foraging behaviour was non-random with respect to both spatial location and the nature of the ground-level habitat. The main feeding areas were within three kilometers of the communal roost, predominantly over the Brisbane River flood plains. As the only mammal capable of flight, bats can forage above fragmented habitats. However, as this study showed, hollow-dependent insectivorous bats, including free-tailed bats, are specialised in their roosting requirements. The ongoing protection of hollow-bearing trees, and the ongoing recruitment of future hollow-bearing trees, is essential for the long-term conservation of these animals in highly fragmented landscapes. Furthermore, loss of foraging habitat is still poorly understood, and should be considered in the ongoing conservation of bats in urban environments.
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Produção de anticorpos monoclonais para caracterização de variantes antigênicas brasileiras de vírus da raiva. / Production of monoclonal antibodies for characterization of brazilian antigenic variants of rabies virus.Chaves, Luciana Botelho 10 May 2010 (has links)
Anticorpos monoclonais (AcMo) contra proteínas do vírus da raiva (RABV) foram produzidos para adequar a caracterização antigênica dos isolados no Brasil. Foram selecionados dois isolados de morcegos insetívoros, sendo um de Nyctinomops laticaudatus e outro de Eptesicus furinalis que apresentaram perfis não compatíveis (NC) com os pré-estabelecidos. As suspensões virais foram adaptadas para crescimento em cultura de células N2A. Para o preparo de AcMo foram utilizadas como antígeno as ribonucleoproteínas dos isolados selecionados. Foram obtidos dois AcMo, o 3A7 e o 4E10. Analisando 57 isolados de RABV com esses AcMo, o 3A7 reagiu com 21 (36,84%) e o 4E10 com 25 (43,85%). Dos 13 isolados caracterizados como variante antigênica 3 (Desmodus rotundus) o 3A7 reagiu com 8 (61,53%) e o 4E10 com 11 (84,61%). Dos 9 isolados com perfil NC em morcegos o 3A7 reagiu com 5 (55,55%) e o 4E10 com 4 (44,44%). Os anticorpos produzidos poderão auxiliar na complementação do painel existente de caracterização antigênica o que poderá aprimorar a vigilância epidemiológica da doença. / Monoclonal antibodies (MAb) against the rabies virus (RABV) proteins were produced to improve the antigenic characterization of the isolates in Brazil. Two isolates from insectivorous bats were selected; one was from the species Nyctinomops laticaudatus and the other from Eptesicus furinalis, which showed non-compatible (NC) profiles from pre-established ones. The viral suspensions were adapted for growth in N2A cells. Ribonucleoproteins from selected isolates were used as antigen for the preparation of Mab. We obtained two Mab, the 3A7 and the 4E10. Of the 57 RABV isolates analyzed with these MAb, the 3A7 reacted with 21 (36.84%) and 4E10 with 25 (43.85%). Of the 13 isolates characterized as antigenic variant 3 (Desmodus rotundus), the 3A7 MAb reacted with 8 (61.53%) and 4E10 with 11 (84.61%). Of the nine isolates with the profile NC of bats the 3A7 reacted with 5 (55.55%) and the 4E10 with 4 (44.44%). The antibodies produced may help to complement the existing panel to antigenic characterization which could improve the disease epidemiological surveillance.
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Bats, insects and pecans: habitat use and ecosystem services of insectivorous bats in a pecan agroecosystem in central TexasBraun de Torrez, Elizabeth Claire 22 January 2016 (has links)
Comprehensive wildlife conservation strategies must include consideration of the agricultural matrix and its integration into the greater landscape. Bats are postulated to provide critical pest suppression services, but the effects of agricultural intensification on insectivorous bats are not clear. Few studies have thoroughly investigated the ecosystem services provided by bats due, in part, to limited understanding of species-specific habitat use in agricultural landscapes, difficulties in prey identification, and the challenge of quantifying the impact of bats on pest populations and crops. My dissertation integrates these components to describe ecological relationships between the insects and bats associated with a pecan agroecosystem in central Texas. Specifically, I focus on the predator-prey relationship between bats and the pecan nut casebearer moth (PNC), a devastating pest of pecans. I begin with a literature review of the ecosystem services of insectivorous bats and the data necessary to thoroughly evaluate these services. I then assess the potential factors influencing species composition and spatio-temporal distributions of bats within the pecan agroecosystem. My results demonstrate higher activity and diversity of bats within the pecan agroecosystem than in the surrounding landscape likely due to roosting opportunities, but species-specific and seasonal differences exist in the effects of management intensity. Next, I investigate direct interactions between bats and PNC by measuring prey consumption patterns. I found that five species of bats prey upon PNC moths during all three critical population peaks prior to insecticide application, but there is variability in consumption among species. Finally, I assess indirect interactions between bats and pecans, by evaluating the effect of bat predation risk on pecan damage by PNC larvae. A negative relationship between foraging activity by bats and both PNC moths and PNC larval damage to pecans provides evidence that bat predation has quantitative downstream effects. My results highlight the conservation value of the agricultural matrix for bats and the complexities of accurately documenting ecosystem services provided by free-ranging mobile organisms.
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Produção de anticorpos monoclonais para caracterização de variantes antigênicas brasileiras de vírus da raiva. / Production of monoclonal antibodies for characterization of brazilian antigenic variants of rabies virus.Luciana Botelho Chaves 10 May 2010 (has links)
Anticorpos monoclonais (AcMo) contra proteínas do vírus da raiva (RABV) foram produzidos para adequar a caracterização antigênica dos isolados no Brasil. Foram selecionados dois isolados de morcegos insetívoros, sendo um de Nyctinomops laticaudatus e outro de Eptesicus furinalis que apresentaram perfis não compatíveis (NC) com os pré-estabelecidos. As suspensões virais foram adaptadas para crescimento em cultura de células N2A. Para o preparo de AcMo foram utilizadas como antígeno as ribonucleoproteínas dos isolados selecionados. Foram obtidos dois AcMo, o 3A7 e o 4E10. Analisando 57 isolados de RABV com esses AcMo, o 3A7 reagiu com 21 (36,84%) e o 4E10 com 25 (43,85%). Dos 13 isolados caracterizados como variante antigênica 3 (Desmodus rotundus) o 3A7 reagiu com 8 (61,53%) e o 4E10 com 11 (84,61%). Dos 9 isolados com perfil NC em morcegos o 3A7 reagiu com 5 (55,55%) e o 4E10 com 4 (44,44%). Os anticorpos produzidos poderão auxiliar na complementação do painel existente de caracterização antigênica o que poderá aprimorar a vigilância epidemiológica da doença. / Monoclonal antibodies (MAb) against the rabies virus (RABV) proteins were produced to improve the antigenic characterization of the isolates in Brazil. Two isolates from insectivorous bats were selected; one was from the species Nyctinomops laticaudatus and the other from Eptesicus furinalis, which showed non-compatible (NC) profiles from pre-established ones. The viral suspensions were adapted for growth in N2A cells. Ribonucleoproteins from selected isolates were used as antigen for the preparation of Mab. We obtained two Mab, the 3A7 and the 4E10. Of the 57 RABV isolates analyzed with these MAb, the 3A7 reacted with 21 (36.84%) and 4E10 with 25 (43.85%). Of the 13 isolates characterized as antigenic variant 3 (Desmodus rotundus), the 3A7 MAb reacted with 8 (61.53%) and 4E10 with 11 (84.61%). Of the nine isolates with the profile NC of bats the 3A7 reacted with 5 (55.55%) and the 4E10 with 4 (44.44%). The antibodies produced may help to complement the existing panel to antigenic characterization which could improve the disease epidemiological surveillance.
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Aerial Insectivorous Birds Linked to Water Quality and Climate in Urbanizing LandscapesCorra, Joseph William 19 June 2019 (has links)
No description available.
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Bats in Urban Sweden : A multiple regression analysis of bats’ relationship to urbanizationAndersson Skog, Nils January 2021 (has links)
Human development continues to use up more physical space in the natural world, threatening the natural habitats of many organisms. To combat the loss of biodiversity science needs to explore what landscape features are important for different organisms so that we can incorporate these into the modern environment. As bats play an important role in many ecosystems and can reflect changes through trophic levels, analyzing their preferred habitats can help planners improve biological diversity of the urban habitat. Using acoustically identified bat sightings from Artportalen.se for the years 2017-2018, this paper studied the habitats of bats in Sweden. Through multiple regression analysis we examine the response in abundance and/or diversity of bats to physical and socio-cultural attributes of the urban habitat. We examined a total of 10160 bats from 18 species in 418 land cover locales and 306 demographical statistical areas with varying degrees of urbanization. Our results indicate that bat abundance and diversity decrease significantly with higher urbanization while deciduous forests are the most important land cover type for all bats. The results also indicate that wealthier areas have less abundance and diversity even when factoring in population density. Species specific analysis suggested that bat species who are better adapted at foraging in open vegetated landscapes and over water were less susceptible to the negative impacts of the urban habitat. We conclude that diverse habitats with a mixture of open vegetated areas, watercourses and broadleaf forests are the most important land features for a diverse bat fauna along with high connectivity via tree cover and linear landscape elements. If urban planning could incorporate these features into the urban habitat, some of the negative impacts of urbanization could be prevented.
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Ecologia alimentar de aves inset?voras de um fragmento de mata dec?dua do extremo norte da Mata Atl?nticaSouto, Glauber Henrique Borges de Oliveira 30 June 2010 (has links)
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Previous issue date: 2010-06-30 / The diet study of birds has contributed historically as a model for use to
understanding ecological patterns and strategies used by several other groups of
vertebrates, which are observed in season patterns and temporal availability of
resources, and other. This study has as objective generate information concerning
the diet of insectivorous birds during rainy season and dry season, as well as analyze
Index food importance, niche overlap, niche breadth, electivity, and seasonal
availability of prey. The study was conducted in a fragment of about 270 ha (center
coordinates and 5 ? 53'S 35 ? 23'W). The sampling of birds occurred between March
2008 and December 2009 in three pre-established trails. Catches of birds were
performed using 10 mist nets placed in line, where each trails was sampled once a
month. Samples of pellets were obtained by means of tartar emetic. Sampling of
availability of prey occurred between February 2009 to December 2009. We used two
methods of sampling (pitfall traps and Shake cloths). We captured 269 individuals of
21 species of insectivorous birds. We collected 4116 invertebrates of which 3259 in
the rainy season and 857 in the dry season. We obtained 174 samples stomach,
where 10 species were exclusively insectivorous diet, nine fed on insect/plant
material, an insect/plant material/vertebrate and one for insect/vertebrate. During the
rainy season was observing difference between the consumption of items with higher
food importance. The Coleoptera was item with higher food importance (73%),
followed by Formicidae (7%) and Araneae (6%). During the dry season, no difference
was found difference between the consumption of items with higher food importance.
The Coleoptera was item with higher food importance (34%), followed by seeds
(29%) and Formicidae (18%). The highest levels of niche overlap occurred during the
rainy season, while the dry season was characterized by high levels of niche
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segregation. This indicates that the local insectivorous birds community was
structured differently between periods. No was found correlation between the values
of niche breadth to the mean weight of the body size. We observed seasonal
patterns in prey availability, with the peak availability of invertebrates observed
seasonal patterns in rainy season. The insectivorous birds selected the same species
richness during both periods, showing a specialized diet. Thamnophilus pelzelni was
the only species that had their diet influenced by seasonality. Regarding the overall
diet of insectivorous birds, observed a high consumption of prey, whose food
availability caused the birds could invest and increase their food resources / O estudo da dieta de aves tem contribu?do, historicamente, como modelo de uso
para o entendimento de padr?es e estrat?gias ecol?gicas utilizados por v?rios outros
grupos de vertebrados, nos quais s?o observados padr?es sazonais e temporais na
disponibilidade de recursos e outros. O presente trabalho objetivou gerar
informa??es referentes ? dieta de aves inset?voras durante os per?odos chuvoso e
seco, bem como analisar import?ncia alimentar, valores de sobreposi??o alimentar,
amplitude de nicho, eletividade e disponibilidade de presas durantes as esta??es
chuvosa e seca. O estudo foi realizado em um fragmento com cerca de 270 ha
(coordenadas centrais 5?53 S e 35?23 W). O per?odo de amostragem das aves
ocorreu entre mar?o de 2008 a dezembro de 2009, em tr?s trilhas pr?-estabelecidas.
As capturas das aves foram realizadas por meio de 10 redes ornitol?gicas dispostas
em linha, onde cada linha de rede foi colocada em uma das trilhas, sendo uma
amostragem de aves realizadas em uma ?nica trilha por m?s. As amostras de
regurgitos foram obtidas por meio do t?rtaro em?tico. As amostragens de
disponibilidade de presas ocorreram entre fevereiro de 2009 a dezembro de 2009,
sendo utilizados amostragens no solo (pitfall traps) e na folhagem (shake cloths).
Capturamos 269 indiv?duos de 21 esp?cies de aves inset?voras. Foram coletados
4.116 invertebrados, dos quais 3.259 no per?odo chuvoso e 857 no per?odo seco.
Obtivemos 174 amostras estomacais, onde 10 esp?cies tiveram dieta
exclusivamente inset?vora, 9 alimentaram-se de inseto/material vegetal, 1 de
inseto/material vegetal/vertebrado e 1 por inseto/vertebrado. Durante o per?odo
chuvoso foi observada diferen?a entre o consumo dos itens com maior Import?ncia
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Alimentar, sendo Coleoptera o item com maior Import?ncia Alimentar (73%), seguido
por Formicidae (7%) e Araneae (6%). Durante o per?odo seco, n?o foi encontrada
diferen?a entre o consumo dos itens com maior import?ncia Alimentar, Sendo
Coleoptera o item com maior Import?ncia Alimentar (34%), seguido por sementes
(29%) e Formicidae (18%). Os maiores ?ndices de sobreposi??o de nicho ocorreram
durante o per?odo chuvoso, enquanto o per?odo seco foi caracterizado pelos maiores
valores de segrega??o de nicho. Isto indica que a comunidade de aves inset?voras
local esteve estruturada de forma diferenciada entre os per?odos. N?o foi encontrada
correla??o entre os valores de Amplitude de nicho com os pesos m?dios das aves,
mostrando que o tamanho do nicho ocupado pelas aves n?o tem rela??o com o seu
tamanho corporal. Foram observados padr?es sazonais na disponibilidade de
presas, sendo o pico da disponibilidade de invertebrados observado durante o
per?odo chuvoso. As aves inset?voras selecionaram a mesma riqueza de esp?cies
durante os dois per?odos, mostrando uma dieta especializada. Thamnophilus
pelzelni foi a ?nica esp?cie que teve a sua dieta influenciada pela sazonalidade. No
que diz respeito a dieta global das aves inset?voras, observamos um elevado
consumo de presas, cuja grande disponibilidade de alimento fez com que as aves
pudessem investir e aumentar os seus recursos alimentares
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Influ?ncia de Planta??es de Banana na assembleia de morcegos (Chiroptera) e na dieta e dispers?o de sementes / Influence of banana plantations in bats (Chiroptera) assemblage, diet and seed dispersal.Luz, J?lia Lins 29 February 2012 (has links)
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Previous issue date: 2012-02-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Modification of the landscape for food production and other facilities for human consumption
is the most common and severe threat to global biodiversity. The aims of this study were to
analyze how banana plantations affect bats assemblages, to check whether the planting of
bananas causes a decrease in the dispersion of seeds, to verify if the abundance of nutritional
resources have some influence on bat abundance and richness in areas of banana plantation, to
verify if bats move between plantations and forest fragments or if they show site fidelity to
the areas. A total of 12 banana plantations in Rio de Janeiro State were sampled. Each month,
from November 2008 to October 2010, two capture nights were conducted, being one night in
a banana plantation area and another in an adjacent forest fragment. Bats were sampled with
mist nets, totaling 142,560 m2.h of sampling effort. Bats were identified, marked, remained in
cloth bags to obtain fecal samples, and released after it. The seeds obtained in fecal samples
were counted and classified. The availability of food resources in banana plantation areas was
estimated in five 100 m2 plots, where the number of banana trees, flowers and fruits was
counted. A total of 2,369 captures and recaptures of bats of 27 species were recorded. In
banana plantations 22 species were recorded (four of which were exclusive to such habitat),
and in fragments 23 (with five exclusive). The capture frequency was higher in plantations
than in fragments. Richness, diversity and evenness were similar between habitats. Artibeus
lituratus, Carollia perspicillata, Glossophaga soricina and Phyllostomus hastatus were more
abundant in the banana plantations. The abundance of frugivores, nectarivores and omnivores
was higher in plantation areas while insectivores were more abundant in forest areas. The
estimated richness for each environment suggests that forest fragments are richer than the
banana plantations. A non-metric multidimensional scaling (NMDS) indicated separation
between banana plantations and forest fragments based on species abundance, using Braycurtis
similarity. We analyzed 1,127 fecal samples from 20 species that had 33 morphotypes
of seeds of 12 plant families. There was presence of banana pulp in fecal samples from 10
species. The richness and abundance of seeds dispersed in the two environments did not
differ, however the abundance of seeds per fecal sample was lower in banana plantations. The
abundance of Sturnira lilium was correlated negatively with the abundance of banana and
fruits. The abundance of G. soricina, A. lituratus, nectarivorous and frugivorous bats showed
positive relationship with the abundance of food resource. We obtained 102 recaptures of 99
individuals of 10 species. The most recaptured species were C. perspicillata, A. lituratus and
P. hastatus. Twenty-eight individuals moved between environments, 68 remained in the same
environment of the capture. In all analyzed cases, the proportion of individuals recaptured in
the same location of capture was higher than the recapture proportion in different
environments. These results reinforce the potential of bats as regenerators in habitats modified
by humans, since banana plantations maintain a diverse assemblage. The ability of bats to
disperse pioneer plants species and the use of different environments assure that nature
services of forest regeneration are continued / A modifica??o da paisagem para a produ??o de alimentos e outras comodidades para
consumo humano representa a mais severa e comum amea?a ? biodiversidade global. Os
objetivos deste trabalho foram analisar como o plantio de bananas afeta a comunidade de
morcegos, analisar se o plantio de bananas diminui a dispers?o de sementes, verificar se a
abund?ncia de recurso alimentar influencia a abund?ncia e a riqueza de morcegos em ?reas de
planta??o de banana, verificar se os morcegos se deslocam entre ?reas de planta??es e
fragmentos florestais e se mant?m fidelidade ? ?rea de captura. Foram selecionadas 12 ?reas
de planta??o do estado do Rio de Janeiro. Mensalmente, entre novembro de 2008 e outubro de
2010, foram realizadas duas noites de coleta, sendo uma em ?rea de planta??o de banana e
outra em um fragmento florestal adjacente. As coletas foram realizadas com redes de neblina,
totalizando 142.560 m2.h de esfor?o amostral. Os morcegos foram identificados,
permaneceram em sacos de pano para obten??o de amostras fecais, e soltos ap?s receberem
marca??o. No laborat?rio, as sementes foram classificadas em morfotipos e contadas. A
disponibilidade de recurso alimentar nas ?reas de planta??o de banana foi estimada atrav?s de
cinco plots de 100 m2 , nos quais era contabilizado o n?mero de bananeiras, infrutesc?ncias e
infloresc?ncias de banana. Um total de 2.369 capturas e recapturas de 27 esp?cies foi
registrado. Nos bananais, foram capturadas 22 esp?cies, sendo quatro exclusivas; nos
fragmentos, 23, sendo cinco exclusivas. A frequ?ncia de captura nos bananais foi maior do
que nos fragmentos. A riqueza, a diversidade e a equitabilidade mostraram-se similares. As
esp?cies significativamente mais abundantes nos bananais foram Artibeus lituratus, Carollia
perspicillata, Glossophaga soricina e Phyllostomus hastatus. A abund?ncia de frug?voros,
nectar?voros e on?voros foi maior em ?reas de plantio, enquanto a de inset?voros foi maior em
?reas de floresta. A riqueza estimada para cada ambiente sugere que os fragmentos florestais
s?o mais ricos do que as ?reas de plantio. Uma an?lise de escalonamento multidimensional
(NMDS) indicou separa??o entre os bananais e os fragmentos florestais baseado no n?mero
de capturas por esp?cie, atrav?s da dist?ncia Bray-curtis. Foram analisadas 1.127 amostras
fecais de 20 esp?cies, que apresentaram sementes de 33 morfotipos de 12 fam?lias de plantas.
Foi poss?vel verificar a presen?a de polpa de banana em amostras fecais de 10 esp?cies. A
riqueza e abund?ncia de sementes dispersadas nos dois ambientes n?o diferiram. No entanto, a
abund?ncia de sementes por amostra fecal foi menor em ?reas de planta??o de banana. A
abund?ncia de Sturnira lilium foi inversamente proporcional ? abund?ncia de bananeiras e
infrutesc?ncias de banana. A abund?ncia de G. soricina, A. lituratus, morcegos nectar?voros e
frug?voros foi diretamente proporcional ? abund?ncia de recurso alimentar. Foram obtidas 102
recapturas de 99 morcegos de 10 esp?cies. As esp?cies mais recapturadas foram C.
perspicillata, A. lituratus e P. hastatus. Vinte e oito indiv?duos transitaram entre os
ambientes, 68 permaneceram no mesmo ambiente da captura e tr?s foram recapturados duas
vezes, uma em cada ambiente. Em todos os casos analisados, a propor??o de indiv?duos
recapturados no mesmo local da captura foi maior do que a propor??o de indiv?duos
recapturados em ambientes diferentes. Em ?reas de planta??o de banana, a ordem Chiroptera
foi capaz de manter uma comunidade diversa, a capacidade de dispers?o de esp?cies pioneiras
de plantas e a capacidade de deslocamento. Esses resultados refor?am o potencial dos
morcegos como regeneradores de habitats modificados pelo homem.
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