Absence Of Bats Research Articles

A One Health approach to investigate bats as a potential source of zoonotic mycoses in selected areas of Mpumalanga province, the Republic of South Africa

A One Health approach pilot study was carried out in selected villages within the Mnisi Traditional Authority’s area, Manyeleti Game Reserve, and Hans Hoheisen Wildlife Research Station in Mpumalanga Province, the Republic of South Africa from July to December 2018. The study’s main objectives were to identify positive and negative human-bat-environment interactions and microbiological screening of bats’ faecal samples for zoonotic fungi. Thirty-three purposively selected participants were asked to complete a structured questionnaire with multiple-choice and open-ended questions, and a total of 55 faecal samples were collected, 25 from identified bat roosting sites and 30 from captured bats. Ninety seven percent of respondents were aware of the presence or absence of bats in their immediate surroundings. However, the majority of them (87.9%) were uneasy about the presence of bats in their buildings, and nearly half (48.5%) were unsure whether bats play a positive or negative role in the environment. Some respondents (15.2%) stated that bats play beneficial roles in the environment, such as pollinating plants, spreading seeds of indigenous plants, catching harmful insects, and so on. More than half of the respondents (66.7%) stated that bats can be a nuisance; 18.2% of those polled reported contracting fungal diseases as a result of cleaning bat droppings without adequate protection. The analysis of faecal samples revealed that bats can harbour pathogenic fungi such as Aspergillus fumigatus, and A.flavus. We concluded that bats can harbour fungal pathogens that cause human diseases. Further research should be conducted to compile a complete list of fungi pathogens in bats in the study area.

Systematics and Ethnobiology of Spineless Leaf Common Pandanus (Pandanus tectorius Parkinson Ex Du Roi; Pandanaceae) from Kelapan Island, Bangka and Belitung, Indonesia

Pandanus tectorius Parkinson ex Du Roi forma integrifolius S. Agustika, S. Santiago and A.P. Keim is a new forma described from Kelapan Island in the Bangka and Belitung Province, Indonesia. This new forma is identified through the distinctive morphological character of spineless leaf margin. These facts are important to be explained related to the unique morphological phenomenon recently discovered in a small population of P. tectorius found in one of the small islands around Bangka Island. The result showed that the phenomenon of spineless leaves in P. tectorius found in Kelapan Island is related with the absence of predator, especially frugivore that consume the fruit of the species. In other words, the complete absence of bats in Kelapan Island apparently triggers the individuals of P. tectorius in the island to stop developing the spines in the leaf margin in order to protect the fruits from predators. The people of Kelapan Island harvest the leaves of P. tectorius for making mats.

Evaluating survey methods for bat roost detection in ecological impact assessment.

The disturbance, damage and destruction of roosts are key drivers of bat population declines worldwide. In countries where bats are protected by law, bat roost surveys are often required to inform ecological impact assessments. Yet, evidence‐based information on survey methodology to detect bat roosts is crucially lacking, and failing to detect a roost can lead to serious errors during decision‐making processes. Here, we assess the efficacy of bat roost surveys in buildings as implemented in the UK. These consist of a daytime inspection of buildings, followed by a series of acoustic surveys at dusk/dawn if during the daytime inspection evidence of bats is found, or if the absence of bats cannot be verified. We reviewed 155 ecological consultants’ reports to (1) compare survey outcome between daytime inspection and acoustic surveys and (2) determine the minimum sampling effort required during acoustic surveys to be confident that no bats are roosting within a building. We focused on two genera of bats most frequently found in buildings in Europe – Pipistrellus (crevice roosting species with high‐intensity echolocation calls that can be easily detected by ultrasound detectors) and Plecotus (species that roost in open spaces and which emit faint echolocation calls that are difficult to detect). Daytime inspections were efficient in detecting open‐roosting species such as Plecotus species but were likely to miss the presence of crevice‐dwelling ones (here Pipistrellus species) which may lead to erroneous conclusions if no acoustic surveys are subsequently prescribed to confirm their absence. A minimum of three and four acoustic surveys are required to be 95% confident that a building does not host a roost of Pipistrellus species and Plecotus species, respectively, thus exceeding current recommendations. Overall, we demonstrated that reports submitted as part of an ecological impact assessment provide suitable data to test and improve survey methods.

Tree selection by roosting bats in a European temperate lowland sub-Atlantic forest

AbstractTrees are the main roosts for several European bat species but forestry practices are most often detrimental for them. After checking for the presence or absence of bats in trees, we collected a number of variables to describe trees within a lowland sub-Atlantic oak-dominated forest. We modelled the usage of the trees by bats according to the main characteristics of trees (11 quantitative and 13 qualitative variables) with a logistical regression analysis. Our results show that the number of cavities in the tree is the main variable that induces the occupancy by bats. There is a “typical” lowland tree preferred by bats which is a healthy oak tree of large diameter. We finally provide some guidance for woodland managers to maintain bat roosts, including maintaining some trees of large diameter, protecting small areas of old trees with cavities).

Long-Term Persistence of Pseudogymnoascus destructans, the Causative Agent of White-Nose Syndrome, in the Absence of Bats.

Wildlife diseases have been implicated in the declines and extinctions of several species. The ability of a pathogen to persist outside its host, existing as an "environmental reservoir", can exacerbate the impact of a disease and increase the likelihood of host extinction. Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome in bats, has been found in cave soil during the summer when hibernating bats had likely been absent for several months. However, whether the pathogen can persist over multiple years in the absence of bats is unknown, and long-term persistence of the pathogen can influence whether hibernacula where bats have been locally extirpated due to disease can be subsequently recolonized. Here, we show that P. destructans is capable of long-term persistence in the laboratory in the absence of bats. We cultured P. destructans from dried agar plates that had been kept at 5°C and low humidity conditions (30-40% RH) for more than 5years. This suggests that P. destructans can persist in the absence of bats for long periods which may prevent the recolonization of hibernation, sites where bat populations were extirpated. This increases the extinction risk of bats affected by this disease.

Release from bats: genetic distance and sensoribehavioural regression in the Pacific field cricket, Teleogryllus oceanicus

The auditory thresholds of the AN2 interneuron and the behavioural thresholds of the anti-bat flight-steering responses that this cell evokes are less sensitive in female Pacific field crickets that live where bats have never existed (Moorea) compared with individuals subjected to intense levels of bat predation (Australia). In contrast, the sensitivity of the auditory interneuron, ON1 which participates in the processing of both social signals and bat calls, and the thresholds for flight orientation to a model of the calling song of male crickets show few differences between the two populations. Genetic analyses confirm that the two populations are significantly distinct, and we conclude that the absence of bats has caused partial regression in the nervous control of a defensive behaviour in this insect. This study represents the first examination of natural evolutionary regression in the neural basis of a behaviour along a selection gradient within a single species.

Presence and Absence of Bats Across Habitat Scales in the Upper Coastal Plain of South Carolina

During 2001, we used active acoustical sampling (Anabat II) to survey foraging habitat relationships of bats on the Savannah River Site (SRS) in the upper Coastal Plain of South Carolina. Using an a priori information-theoretic approach, we conducted logistic regression analysis to examine presence of individual bat species relative to a suite of microhabitat, stand, and landscape-level features such as forest structural metrics, forest type, proximity to riparian zones and Carolina bay wetlands, insect abundance, and weather. There was considerable empirical support to suggest that the majority of the activity of bats across most of the 6 species occurred at smaller, stand-level habitat scales that combine measures of habitat clutter (e.g., declining forest canopy cover and basal area), proximity to riparian zones, and insect abundance. Accordingly, we hypothesized that most foraging habitat relationships were more local than landscape across this relatively large area for generalist species of bats. The southeastern myotis (Myotis austroriparius) was the partial exception, as its presence was linked to proximity of Carolina bays (best-approximating model) and bottomland hardwood communities (other models with empirical support). Efforts at SRS to promote open longleaf pine (Pinus palustris) and loblolly pine (P. taeda) savanna conditions and to actively restore degraded Carolina bay wetlands will be beneficial to bats. Accordingly, our results should provide managers better insight for crafting guidelines for bat habitat conservation that could be linked to widely accepted land management and environmental restoration practices for the region.

ROOST SELECTION BY FOREST-LIVING FEMALE BIG BROWN BATS (EPTESICUS FUSCUS)

Previous studies of forest-dwelling bats have identified physical features of trees and forests that correlate with the presence of bats by comparing roost sites to paired, randomly selected sites. This method may be limited if the absence of bats from random sites cannot be confirmed. Our purpose was to address roosting ecology of female big brown bats (Eptesicus fuscus) using a different approach. We quantified relative use of trees with 3 different types of cavity openings (long crevices, multiple holes, or single holes) and compared the relative use of these potential roosts to the availability of each roost type in the study area. Bats used trees with multiple holes and crevices significantly more often than expected based on their availability and trees with single holes less often than expected. Crevice roosts had significantly larger cavities than did single holes and roosting-group size was positively correlated with cavity volume. No relationship was found between cavity volume and tree height or stem diameter of roost trees, 2 variables that have been reported to correlate with roost selection in other studies of forest bats. Examination of our data suggests that the volume of roost cavities may be an important selection criterion for colonial, forest-living bats and that standard interpretations of the roost versus random-tree approach may not accurately identify patterns of roost selection in some systems.

Taxonomy, status and distribution of the Azorean bat (Nyctalus azoreum)

The taxonomic status of the Azorean bat (Nyctalus azoreum Thomas 1901) was assessed, by a principal components analysis of measurements of the external morphology of the bat, together with specimens of the closest related Nyctalus species from mainland Europe (Nyctalus leisleri). This analysis confirms the recent suggestion, based on a similar analysis of skull morphology, that the Azorean bat represents a good species, distinguished from N. leisleri by its smaller size—forearm lengths for N. azoreum in range 35·7–42·0 mm (n= 14). compared with 42·0−45·8 mm (n = 8) for N. leisleri. The status and distribution of the Azorean bat was assessed by a survey conducted in the islands in September and October 1988. We assessed the presence or absence of bats, in 62(1′ latitude × 1′ longitude) plots at the west end of the island of Sao Miguel. The study area covered 6% of the total land area of the archipelago and contained representative areas of all the major island habitat types. A less intensive survey throughout four other islands, literature review and information from other sources revealed that the bat is probably distributed throughout the entire archipelago, with the possible exception of Flores and Corvo. Bats were active both in the day and at night. At night, bats were mostly active in coastal villages where they were closely associated with street lighting. During the day, most hats were active in the inland areas near to Caldeira lakes. The maximum number of bats observed simultaneously active in the day was six whilst at dusk swarms of up to 55 (± 5) bats were observed together. At night, bats were also active over approximately 1·5 × the area they occupied in the day. By assuming the bat is found throughout the archipelago, and that our study area was representative, we estimated the maximum population to be between 1750 (from daylight activity) and 23,650 (from nocturnal activity). This latter estimate implies a population density throughout the archipelago of around 0·1 bats per hectare.

Harem Social Organization in Cave Roosting Artibeus jamaicensis (Chiroptera: Phyllostomidae)

Harem Social Organization in Cave Roosting Artibeus jamaicensis (Chiroptera: Phyllostomidae)

Insular Biogeography in Continental Regions. II. Cave Faunas from Tessin, Southern Switzerland

Vuilleumier, François. (Station de biologie marine, Roscoff, Nord-Finistère, France) 1973. Insular Biogeography in Continental Regions. II. Cave Faunas from Tessin, Southern Switzerland. Syst. Zool. 22:64–76.—The suggestion that caves are habitat islands was investigated by analyzing species diversity and endemism in a set of 48 caves from Tessin, southern Switzerland, using stepwise multiple regression. Measures of environmental diversity (development, representing area; water content; and the presence or absence of bats, representing the presence of guano) and of isolation (altitude, geographical coordinates, clustering of caves) were expected to contribute to the regulation of species diversity and of numbers of endemic taxa. From 50% to 58% of the variance in numbers of species and of endemics can be accounted for with five independent variables in the regression equations. The Tessin caves can be considered insular insofar as an area affect is demonstrated for the total number of species and for the number of endemics, and as a measure of isolation (altitude) helps in accounting for endemism. Deviation from the insular biogeography theory stems from the lack of isolation or distance effects for the numbers of species (whether troglobitic or not), and from the lack of area effect for the troglophiles and troglobites. The number of species of troglophiles and troglobites is correlated with the water scale, and since the latter is correlated with development one can argue that water scale represents an improved measure of habitat diversity over area. The water scale may be an indirect measure of (i) the food input, or (ii) the rigor of the caves in terms of flooding, or else (iii) dispersal. The lack of isolation or distance effect may be attributed to the geographical nearness of the Tessin caves, which can be likened to islands equidistant from the mainland or source region.