Conservation status and causes of decline of the threatened New Zealand Long-tailed Bat Chalinolobus tuberculatus (Chiroptera: Vespertilionidae)

Historical anecdotes and preliminary monitoring since 1990 indicate that New Zealand Long‐tailed Bats (Chalinolobus tuberculatus, Vespertilionidae) are now rare or absent at many sites where formerly they were common. Chalinolobus tuberculatus appeared to be common throughout New Zealand in the 1800s but by 1900–30 it was becoming scarce in many districts. Formal surveys in the South Island since 1990 either failed to find C. tuberculatus, or recorded bats in low numbers. Of eight sites where transect counts were undertaken, bats were recorded frequently at two sites (45–66% of counts; Eglinton and Dart Valleys), rarely at four sites (2.4–10.7% of counts), and were not recorded at the remaining two sites despite considerable survey effort. Of 10 sites where stationary counts using automatic detector units were used, no C. tuberculatus were recorded in three areas (153 nights combined), they were found rarely at six sites (2.1–21.0% of nights; 461 nights combined) and were recorded commonly only in the Eglinton Valley (85% of 120 nights). Assertions that C. tuberculatus are ‘common’ and that the conservation status is ‘secure’ are questionable and this review supports suggestions that the species should be classed as ‘Vulnerable’. Possible causes of decline have been suggested including clearance and logging of lowland forests, predation by introduced mammals and owls, competition for roost sites by introduced mammals, birds and wasps, and human interference and disturbance at roosting sites. However, authors’ claims have all been speculative and unsubstantiated. There has been no research undertaken to quantify these claims, and this is required urgently. The results of these preliminary surveys provide a new baseline against which future population trends might be compared. Increased effort using standardized monitoring techniques, applied at a national level, is required to confirm the possible trends and to help identify the best sites where conservation managers may attempt to restore the population level.     

Bats in bird nests in Australia: a review

Bats (Microchiroptera) utilize few types of bird nests as roosts. Ten species of bats (Molossidae and Vespertilionidae) were recorded roosting in the enclosed bottle-shaped mud nests of the Fairy Martin Hirundo ariel; two species (Vespertilionidae) were located in the hanging nests of scrubwrens Sericornis spp. and the Brown Gerygone Gerygone mouki; two species (Vespertilionidae) in the enclosed plant material nests of the Grey-crowned Babbler Pomatostomus temporalis and Fernwren Oreoscopus gutturalis; and one species (Emballonuridae) was recorded in the open cup-shaped nest of the White-rumped Swiftlet Collocalia spodiopygius. No information was available on the importance of bird nests as breeding sites and only one species, the Chocolate Wattled Bat Chalinolobus morio, has been recorded hibernating in a nest. Bird nests in Australia provide roosting habitat for four threatened bats and may be important to the conservation of these species.     

Evidence of homing following translocation of long‐tailed bats (Chalinolobus tuberculatus) at Grand Canyon Cave,New Zealand

Abstract

Homing behaviour in the New Zealand long‐tailed bat (Chalinolobus tuberculatus), a temperate insectivorous species, was investigated at Grand Canyon Cave, central North Island. A pilot study of nine adult male bats was conducted to determine whether use of the cave was regular enough for a homing study. Eight bats returned to the cave over the 3‐week monitoring period, six on the night following release. Nine additional bats carrying radio transmitters were then released at three sites (three at each site) c. 5, 10 and 20 km due east of the cave; sites estimated to be located within, on the border of, and outside the population's known familiar area respectively. All but one of these nine bats were subsequently detected at the cave. Results suggest that adult long‐tailed bats are able to return home following displacement both inside and outside their familiar area. Implications of these findings for translocations of bats and the possession of a potential long‐distance navigation system by this species are discussed.     

Low Rates of PIT-Tag Loss in an Insectivorous Bat Species

The rate of loss of tags used to mark individuals is an important consideration in wildlife research and monitoring. Passive integrated transponder (PIT) tags (or microchips) generally have high retention rates; however, tag loss rates for small mammals such as insectivorous bats are poorly understood. We double-marked a population of Gould's wattled bats (Chalinolobus gouldii) with forearm bands and PIT tags (with the injection site sealed with surgical adhesive) in January and February 2020 to determine rates of subsequent tag loss over the short- (1–2 months) and medium- (13–14 months) term. Loss of PIT tags occurred in 4 (2.7%) of 146 recaptured individuals, all within 2 months of microchipping. We also recorded 1 occurrence of band loss 11 months after banding. Our study supports assertions that PIT-tag retention rates in small mammals are high, and suggests that rates of tag loss in small bat species are low when surgical adhesive is applied. Quantifying the rate of tag loss enables this variable to be incorporated into mark-recapture models. © 2021 The Wildlife Society.     

Bat boxes in urban bushland are associated with inflated activity of an urban generalist bat,but not an altered community

Bat boxes are often installed as substitute habitats to offset the loss of large, hollow-bearing trees. However, emerging evidence suggests that they are failing to achieve intended conservation outcomes as they only support generalist species. Despite these concerns, the effect of bat boxes on the dynamics of bat communities remains understudied. We assessed the bat community in reserves where bat boxes had been installed in comparison with reserves where they had not using ultrasonic surveys in 16 small bushland reserves throughout Sydney, Australia. Reserves containing bat boxes and those without had comparable species diversity and composition; however, the activity of the dominant species, Gould's wattled bat (Chalinolobus gouldii), was significantly higher at sites with bat boxes. Species that commonly forage in open vegetation, including C. gouldii, were significantly positively associated with sites that had bat boxes. Occupation of boxes by bats was not recorded in the study due to limited information on their locations, so further research is required to understand the direct effects of boxes and the bats that occupy them on the bat community. If bat boxes continue to be recommended as a biodiversity offset, a greater understanding of the potential impact they have on altered competitive relationships and community dynamics is essential.     

A comparison of two bat detectors: which is most likely to detect New Zealand’s Chalinolobus tuberculatus?

ABSTRACT

The presence of bat species is commonly determined by placing acoustic bat detectors that record bat echolocation calls in the habitat they are likely to use. Detection rates are affected by variables including type of detection unit used. We compared detection rates of long-tailed bat (Chalinolobus tuberculatus) echolocation calls between two types of automated bat detectors: Wildlife Acoustics SMZC Zero Crossing Bat Recorders (ZC), and Frequency Compression Automated Bat Monitoring units (FC) produced by New Zealand’s Department of Conservation. Units were placed in locations where bats were known to be present, but not all detected bats. The median number of bat passes recorded by FC units over 10 nights was 20 compared with a median of 3 bat passes for ZC units. ZC units also detected bats over significantly fewer nights than FC units. These results suggest FC units are more sensitive and therefore better to use where long-tailed bats are expected to be at low abundance or only present infrequently. Because of inconsistencies in detection rates, we recommend the use of only one model of the detector within a monitoring project. Our data also suggests that surveys should take place over long periods to maximise likelihood of detecting bats, if present.     

Microsatellite markers for the Indian golden silkmoth, Antheraea assama (Saturniidae: Lepidoptera)

Antheraea assama, an economically important and scientifically unexplored Indian wild silkmoth, is unique among saturniid moths. For this species, a total of 87 microsatellite markers was derived from 35 000 expressed sequence tags and a microsatellite‐enriched sub‐genomic library. Forty individuals collected from Tura and West Garo Hills region of Northeast India were screened for each of these loci. Ten loci from expressed sequence tags and one from genomic library were found to be polymorphic. These microsatellite markers will be useful resources for population genetic studies of A. assama and other closely related species of saturniids. This is the first report on development of microsatellite markers for any saturniid species.     

Interspecific microsatellite markers for the study of pinniped populations

Microsatellites have rapidly become the marker of choice for a wide variety of population genetic studies. Here we describe 20 pinniped microsatellite markers which have been tested across 18 pinniped species. The majority of these markers have broad utility in all pinnipeds and provide a strong base for detailed population genetic studies in the Pinnipedia.     

Development and characterization of microsatellite markers for the poplar rust fungi Melampsora medusae and Melampsora larici‐populina

Melampsora species and their hybrids are obligate parasites of Populus and Salix species worldwide. The increasing interest in Populus and Salix for biomass and fibre production necessitates genetic markers for population studies of Melampsora spp. Libraries enriched for simple sequence repeats were used to develop five microsatellite markers for Melampsora medusae and Melampsora larici‐populina. The variation detected by these markers will be valuable for phylogenetic and population genetic studies, substantiate putative hybrids, and deployment of resistant poplar clones.     

Characterization of comparative genome‐derived simple sequence repeats for acanthopterygian fishes

Simple sequence repeats (SSRs) have become one of the most popular molecular markers for population genetic studies. The application of SSR markers has often been limited to source species because SSR loci are too labile to be maintained in even closely related species. However, a few extremely conserved SSR loci have been reported. Here, we tested for the presence of conserved SSR loci in acanthopterygian fishes, which include over 14 000 species, by comparing the genome sequences of four acanthopterygian fishes. We also examined the comparative genome‐derived SSRs (CG‐SSRs) for their transferability across acanthopterygian fishes and their applicability to population genetic analysis. Forty‐six SSR loci with conserved flanking regions were detected and examined for their transferability among seven nonacanthopterygian and 27 acanthopterygian fishes. The PCR amplification success rate in nonacanthopterygian fishes was low, ranging from 2.2% to 21.7%, except for Lophius litulon (Lophiiformes; 80.4%). Conversely, the rate in most acanthopterygian fishes exceeded 70.0%. Sequencing of these 46 loci revealed the presence of SSRs suitable for scoring while fragment analysis of 20 loci revealed polymorphisms in most of the acanthopterygian fishes. Population genetic analysis of Cottus pollux (Scorpaeniformes) and Sphaeramia orbicularis (Perciformes) using CG‐SSRs showed that these populations did not deviate from linkage equilibrium or Hardy–Weinberg equilibrium. Furthermore, almost no loci showed evidence of null alleles, suggesting that CG‐SSRs have strong resolving power for population genetic analysis. Our findings will facilitate the use of these markers in species in which markers remain to be identified.     

MICROSATELLITE GENOTYPING OF SINGLE CELLS OF THE DINOFLAGELLATE SPECIES LINGULODINIUM POLYEDRUM (DINOPHYCEAE): A NOVEL APPROACH FOR MARINE MICROBIAL POPULATION GENETIC STUDIES1

In recent years, two new approaches have been introduced in genetic studies of phytoplankton species. One is the application of highly polymorphic microsatellite markers, which allow detailed population genetic studies; the other is the development of methods that enable the direct genetic characterization of single cells as an alternative to clonal cultures. The aim of this study was to combine these two approaches in a method that would allow microsatellite genotyping of single phytoplankton cells, providing a novel tool for high‐resolution population genetic studies. The dinoflagellate species Lingulodinium polyedrum (F. Stein) J. D. Dodge was selected as a model organism to develop this novel approach. The method we describe here is based on several key developments: (i) a simple and efficient DNA extraction method for single cells, (ii) the characterization of microsatellite markers for L. polyedrum, (iii) a protocol for the species identification of single cells through the analysis of partial rRNA gene sequences, and (iv) a two‐step multiplex PCR protocol for the simultaneous amplification of microsatellite markers and partial rRNA gene sequences from single cells. Our protocol allowed the amplification of up to six microsatellite loci together with either the complete ITS1‐5.8S‐ITS2 region or a partial 18S region of the ribosomal gene of L. polyedrum from single motile cells and resting cysts. This article describes and evaluates the developed approach and discusses its significance for population genetic studies of L. polyedrum and other phytoplankton species.     

Temperature regulation and metabolism of an Australian bat, Chalinolobus gouldii (Chiroptera: Vespertilionidae) when euthermic and torpid

The thermal and metabolic physiology of Chalinolobus gouldii, an Australian vespertilionid bat, was studied in the laboratory using flow-through respirometry. Chalinolobus gouldii exhibits a clear pattern of euthermic thermoregulation, typical of endotherms with respect to body temperature and rate of oxygen consumption. The basal metabolic rate of euthermic Chalinolobus gouldii is approximately 86% of that predicted for a 17.5-g mammal and falls into the range of mass-specific basal metabolic rates ascribed to vespertilionid bats. However, like most vespertilionid bats, Chalinolobus gouldii displays extreme thermolability. It is able to enter into torpor and spontaneously arouse at ambient temperatures as low as 5 °C. Torpid bats thermoconform at moderate ambient temperature, with body temperature ≈ ambient temperature, and have a low rate of oxygen consumption determined primarily by Q ₁₀ effects. At low ambient temperature (< 10 °C), torpid C. gouldii begin to regulate their body temperature by increased metabolic heat production; they tend to maintain a higher body temperature at low ambient temperature than do many northern hemisphere hibernating bats. Use of torpor leads to significant energy savings. The evaporative water loss of euthermic bats is relatively high, which seems unusual for a bat whose range includes extremely arid areas of Australia, and is reduced during torpor. The thermal conductance of euthermic C. gouldii is less than that predicted for a mammal of its size. The thermal conductance is considerably lower for torpid bats at intermediate body temperature and ambient temperature, but increases to euthermic values for torpid bats when thermoregulating at low ambient temperature. Accepted: 22 August 1996     

Revisiting comparisons of genetic diversity in stable and declining species: assessing genome‐wide polymorphism in North American bumble bees using RAD sequencing

Genetic variation is of key importance for a species’ evolutionary potential, and its estimation is a major component of conservation studies. New DNA sequencing technologies have enabled the analysis of large portions of the genome in nonmodel species, promising highly accurate estimates of such population genetic parameters. Restriction site‐associated DNA sequencing (RADseq) is used to analyse thousands of variants in the bumble bee species Bombus impatiens, which is common, and Bombus pensylvanicus, which is in decline. Previous microsatellite‐based analyses have shown that gene diversity is lower in the declining B. pensylvanicus than in B. impatiens. RADseq nucleotide diversities appear much more similar in the two species. Both species exhibit allele frequencies consistent with historical population expansions. Differences in diversity observed at microsatellites thus do not appear to have arisen from long‐term differences in population size and are either recent in origin or may result from mutational processes. Additional research is needed to explain these discrepancies and to investigate the best ways to integrate next‐generation sequencing data and more traditional molecular markers in studies of genetic diversity.     

EvolMarkers: a database for mining exon and intron markers for evolution, ecology and conservation studies

Recent innovations in next-generation sequencing have lowered the cost of genome projects. Nevertheless, sequencing entire genomes for all representatives in a study remains expensive and unnecessary for most studies in ecology, evolution and conservation. It is still more cost-effective and efficient to target and sequence single-copy nuclear gene markers for such studies. Many tools have been developed for identifying nuclear markers, but most of these have focused on particular taxonomic groups. We have built a searchable database, EvolMarkers, for developing single-copy coding sequence (CDS) and exon-primed-intron-crossing (EPIC) markers that is designed to work across a broad range of phylogenetic divergences. The database is made up of single-copy CDS derived from BLAST searches of a variety of metazoan genomes. Users can search the database for different types of markers (CDS or EPIC) that are common to different sets of input species with different divergence characteristics. EvolMarkers can be applied to any taxonomic group for which genome data are available for two or more species. We included 82 genomes in the first version of EvolMarkers and have found the methods to be effective across Placozoa, Cnidaria, Arthropod, Nematoda, Annelida, Mollusca, Echinodermata, Hemichordata, Chordata and plants. We demonstrate the effectiveness of searching for CDS markers within annelids and show how to find potentially useful intronic markers within the lizard Anolis.     

Isolation and characterization of microsatellite loci in wheat stem sawfly Cephus cinctus and cross‐species amplification in related species

The wheat stem sawfly is an important insect pest of wheat that can cause significant damage to yield and grain quality. Five microsatellite loci were isolated and characterized in wheat stem sawfly, Cephus cinctus, to facilitate future population genetic studies and help delineate their geographical origin. These loci were found to be polymorphic with an expected heterozygosity ranging from 0.304 to 0.937 and an observed heterozygosity ranging from 0.05 to 0.65. Successful cross‐species amplification demonstrates the potential for these markers to provide a valuable tool for future population studies among related Cephus species.     

Isolation and characterization of polymorphic microsatellite loci in muskrat, Ondatra zibethicus

We describe the isolation and characterization of 12 highly polymorphic microsatellite loci for the muskrat, Ondatra zibethicus. Microsatellite markers from three other rodent species were cross-amplified in muskrat and one of them was polymorphic. We observed moderate to high levels of genetic variability in these 13 polymorphic loci (five to 22 alleles per locus) with observed heterozygosity ranging from 0.48 to 0.96. These markers will be useful for further studies on population genetic structure in muskrat and potentially in other rodent species.     

Development and cross‐species amplification of 18 microsatellite markers in the Sumatran tiger (Panthera tigris sumatrae)

Eighteen polymorphic microsatellite loci from the highly endangered Sumatran tiger (Panthera tigris sumatrae) were isolated and characterized. Upon polymerase chain reaction amplification, 16 of these markers produced a single, sharp band in all three tiger and 10 non‐tiger felid species examined. Of the two remaining loci, 6HDZ057 and 6HDZ635 failed to amplify genomic DNA from puma (Felis concolor) and cheetah (Acinonyx jubatus), respectively. The amplification of these markers across four genera is an indication of their usefulness for population genetics studies and conservation work in a wide range of felid species.     

PERMANENT GENETIC RESOURCES: Microsatellite markers for the threatened Bliss Rapids snail (Taylorconcha serpenticola) and cross-amplification in its congener, T. insperata

We developed and tested microsatellite markers to investigate population structure of a threatened North American freshwater gastropod, Taylorconcha serpenticola. Of the 21 primer pairs that were evaluated, 11 were readily optimized and scored, providing amplification of 12 loci that were screened for 820 specimens from 29 populations. The number of alleles across 11 of these polymorphic loci ranged from three to 20 and the observed heterozygosity varied from 0.0061 to 0.7561. All loci yielded suitable amplification products in the second species of Taylorconcha (T. insperata) and three proved to be diagnostic for these congeners, demonstrating that these markers are also useful for species identification studies.