Abstract View

Torres, L. G., Smith, T. D., Sutton, P., MacDiarmid, A., Bannister, J., Miyashita, T. (2013), From exploitation to conservation: habitat models using whaling data predict distribution patterns and threat exposure of an endangered whale. Diversity and Distributions. doi: 10.1111/ddi.12069
Sufficient data to describe spatial distributions of rare and threatened populations are typically difficult to obtain. For example, there are minimal modern offshore sightings of the endangered southern right whale, limiting our knowledge of foraging grounds and habitat use patterns. Using historical exploitation data of southern right whales (SRW), we aim to better understand their seasonal offshore distribution patterns in relation to broad-scale oceanography, and to predict their exposure to shipping traffic and response to global climate change.
Australasian region between 130° W and 100° E, and 30° S and 55° S.
We model 19th century whaling data with boosted regression trees to determine functional responses of whale distribution relative to environmental factors. Habitat suitability maps are generated and we validate these predictions with independent historical and recent sightings. We identify areas of increased risk of ship-strike by integrating predicted whale distribution maps with shipping traffic patterns. We implement predicted ocean temperatures for the 2090–2100 decade in our models to predict changes in whale distribution due to climate change.
Temperature in the upper 200 m, distance from the subtropical front, mixed layer depth, chlorophyll concentration and distance from ridges are the most consistent and influential predictors of whale distribution. Validation tests of predicted distributions determined generally high predictive capacity. We identify two areas of increased risk of vessel strikes and predict substantial shifts in habitat suitability and availability due to climate change.
Main conclusions
Our results represent the first quantitative description of the offshore foraging habitat of SRW. Conservation applications include identifying areas and causes of threats to SRW, generating effective mitigation strategies, and directing population monitoring and research efforts. Our study demonstrates the benefits of incorporating unconventional datasets such as historical exploitation data into species distribution models to inform management and help combat biodiversity loss.

Young, M. K., McKelvey, K. S., Pilgrim, K. L. and Schwartz, M. K. (2013), DNA barcoding at riverscape scales: assessing biodiversity among fishes of the genus Cottus (Teleostei) in northern Rocky Mountain streams. Molecular Ecology Resources. doi: 10.1111/1755-0998.12091
There is growing interest in broad-scale biodiversity assessments that can serve as benchmarks for identifying ecological change. Genetic tools have been used for such assessments for decades, but spatial sampling considerations have largely been ignored. Here, we demonstrate how intensive sampling efforts across a large geographical scale can influence identification of taxonomic units. We used sequences of mtDNA cytochrome c oxidase subunit 1 and cytochrome b, analysed with maximum parsimony networks, maximum-likelihood trees and genetic distance thresholds, as indicators of biodiversity and species identity among the taxonomically challenging fishes of the genus Cottus in the northern Rocky Mountains, USA. Analyses of concatenated sequences from fish collected in all major watersheds of this area revealed eight groups with species-level differences that were also geographically circumscribed. Only two of these groups, however, were assigned to recognized species, and these two assignments resulted in intraspecific genetic variation (>2.0%) regarded as atypical for individual species. An incomplete inventory of individuals from throughout the geographical ranges of many species represented in public databases, as well as sample misidentification and a poorly developed taxonomy, may have hampered species assignment and discovery. We suspect that genetic assessments based on spatially robust sampling designs will reveal previously unrecognized biodiversity in many other taxa.

Amulike, B., Stevens, S. S. and Serfass, T. L. (2013), Enhancing tourist opportunities to view spotted-necked otters (Lutra maculicollis) at Rubondo Island National Park: can the apriori location of latrines simplify identifying best viewing areas?. African Journal of Ecology. doi: 10.1111/aje.12077
We observed spotted-necked otters (Lutra maculicollis) along a 5.17-km section of shoreline at Rubondo Island National Park, Tanzania, during May 2008 and February, June–August 2009 to determine whether their activity areas were associated with latrine site (places along the shoreline where spotted-necked otters scent mark by depositing scats and urine) as part of an assessment to determine how tourists or researchers can best view the species. For this assessment, we compared the distance of spotted-necked otters sightings associated with the shoreline (n = 207) with the distance between an equal number of geographical information system (GIS)-generated random points to the nearest latrine for each of the respective points. The mean distances for locations of spotted-necked otter sightings to the nearest latrine differed from the mean distance of random points to latrines [171.9 m (SE = 11.30) and 66.1 m (SE = 8.16), respectively; t = −9.23, df = 412, P < 0.001]. Sightings also were much (2.6 times) closer to latrines that occurred in groups than those that were isolated (single). Establishing viewing sites at or near latrines (particularly those occurring in clusters) would thus seem an effective way to maximize opportunities to see spotted-necked otters.

Hochscheid, S., Travaglini, A., Maffucci, F., Hays, G. C. and Bentivegna, F. (2013), Since turtles cannot talk: what beak movement sensors can tell us about the feeding ecology of neritic loggerhead turtles, Caretta caretta. Marine Ecology. doi: 10.1111/maec.12018
Understanding the role that consumers play in an ecosystem requires knowledge about food selection and intake rates. However, such basic data are often difficult to obtain, particularly for marine animals that are not easy to observe. To overcome this problem, a beak movement sensor was employed on a free-ranging loggerhead turtle in a neritic foraging habitat at the Domitian littoral (SW Italy). In combination with gastrointestinal content analysis from six turtles found dead in the same area we sought to identify which beak movement patterns were associated with which prey type, and to quantify the ingestion of the various prey types. Brachyuran crabs (100% occurrence), in particular Liocarcinus vernalis, and small molluscs (66% occurrence) were found most frequently in the stomach and intestine of the turtles. Beak movements revealed average ingestion rates of (mean ± SE) 0.27 ± 0.13 food items per minute and that feeding occurred predominantly during dives >4 m and during early morning and evening. Interestingly, the time spent feeding amounted to only 2.2% of the total observation time, whereas feeding-associated dives added up to just above 10% of the total time. We thus established that loggerhead turtles in this area are specialised on brachyuran crabs, on which they prey with high success during the short time dedicated to foraging. This information strengthens our knowledge about turtle–prey and turtle–habitat interactions, which are essential data to delineate the role that turtles play in this and similar marine ecosystems. Moreover, since the same area is also intensively used by the regional bottom trawl fishery, our results have important conservation implications, because they clearly show the time of day and water depths for which fishing activity should be regulated to reduce the number of turtles that are currently being incidentally caught in this area.

Md Harunur Rashid, Chunyi Xue, Md Rafiqul Islam, Md Taohidul Islam, Yongchang Cao, A longitudinal study on the incidence of mortality of infectious diseases of commercial layer birds in Bangladesh, Preventive Veterinary Medicine, Volume 109, Issues 3–4, 1 May 2013, Pages 354-358, ISSN 0167-5877, 10.1016/j.prevetmed.2012.10.012.
A 20-month longitudinal field study was undertaken during the period from January 2010 to August 2011 to determine the incidence of mortality due to infectious diseases affecting commercial layer birds in 8 upazilas (an administrative unit) of 5 different districts in Bangladesh. Diagnosis of different diseases was made based on the flock history, age of birds, clinical signs, characteristic gross and microscopic lesions, and isolation and identification of the organisms. During the study period, 4710 birds were found dead as a result of disease occurrence. The incidence rate (true incidence rate) of mortality for the study period was 0.0171 per bird-months at risk. The incidences of mortality of almost all the infectious diseases were significantly higher in rainy followed by summer seasons. Particularly, mortality rate of ND and FC was significantly higher in rainy and summer seasons compared to winter and autumn seasons. And higher mortality rate of IBD, salmonellosis, IB, colibacillosis and MD was found in rainy than other three seasons. The highest mortality was recorded in birds below 8 weeks of age followed by birds aged 21 weeks and above. The mortality due to IBD was significantly higher (0.006) in the young birds (<8 weeks of age) than older birds. On the other hand, mortality rate of ND was significantly higher (0.003) in older birds (>8 weeks of age). Statistically no significant difference (p > 0.05) was observed in the mortality rate of colibacillosis between different age groups. The proportional mortality due to infectious diseases was 54.2% (including single or mixed infections). Of the overall mortality, 13.4% was attributed to ND, 9.53% to IBD, 6.69% to MD, 4.33% to IB, 4.23% to salmonellosis, 3.23% to FC, 3.31% to colibacillosis, 1.1% to aspergillosis and 45.8% to non-infectious causes. The findings indicated that infectious diseases appear to be a major constraint of commercial layer birds in Bangladesh.

Paolo Dalla Villa, Stefano Messori, Luigi Possenti, Shanis Barnard, Mara Cianella, Cesare Di Francesco, Pet population management and public health: A web service based tool for the improvement of dog traceability, Preventive Veterinary Medicine, Volume 109, Issues 3–4, 1 May 2013, Pages 349-353, ISSN 0167-5877, 10.1016/j.prevetmed.2012.10.016.
The risks associated with zoonotic infections transmitted by companion animals are a serious public health concern: the control of zoonoses incidence in domestic dogs, both owned and stray, is hence important to protect human health. Integrated dog population management (DPM) programs, based on the availability of information systems providing reliable data on the structure and composition of the existing dog population in a given area, are fundamental for making realistic plans for any disease surveillance and action system. Traceability systems, based on the compulsory electronic identification of dogs and their registration in a computerised database, are one of the most effective ways to ensure the usefulness of DPM programs. Even if this approach provides many advantages, several areas of improvement have emerged in countries where it has been applied. In Italy, every region hosts its own dog register but these are not compatible with one another. This paper shows the advantages of a web-based-application to improve data management of dog regional registers. The approach used for building this system was inspired by farm animal traceability schemes and it relies on a network of services that allows multi-channel access by different devices and data exchange via the web with other existing applications, without changing the pre-existing platforms. Today the system manages a database for over 300,000 dogs registered in three different Italian regions. By integrating multiple Web Services, this approach could be the solution to gather data at national and international levels at reasonable cost and creating a traceability system on a large scale and across borders that can be used for disease surveillance and development of population management plans.

Bauer, A. M. and Günther, R. (2013), Origin and identity of the von Borcke collection of amphibians and reptiles in the Museum für Naturkunde in Berlin: A cache of Seba specimens?. Zool. Reihe, 89: 167–185. doi: 10.1002/zoos.201300005
Approximately 150 specimens of amphibians and reptiles donated by Graf von Borcke in the first years of the museum’s existence are still present in the Museum für Naturkunde, Berlin (ZMB). Based on information published by Blasius Merrem and additional historical sources, it can be determined that a portion of von Borcke’s collection was purchased from the estate of Willem Xaver Janssen (= Wilhelm Xaver Jansen) and that this was probably obtained indirectly (possibly via Adrianus van Royen) from the second collection of Albertus Seba, auctioned in 1752. Comparison of the von Borcke material with Seba’s illustrations reveals five credible and 18 questionable matches. Most convincing is a specimen of Python sebae partly dissected to show a bird in its abdomen. The Seba figure of this specimen is an iconotype of Python bivittatus Kuhl, 1820. An additional ten ZMB specimens are possible matches to Seba illustrations that have served as iconotypes. The stylized appearance of many of Seba’s figures, particularly those of snakes, makes the unambiguous identification of surviving Seba specimens difficult. In addition, five snake specimens are probable matches to specimens from Janssen’s collection that were described and figured by Merrem. Three of these are type specimens of subsequently described species, including the widespread and invasive Boiga irregularis (Bechstein, 1802). A combination of historical information and specimen correspondences yields a strong case for the survival of a large part of Seba’s herpetological collection in Berlin. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Martins, F. M.S., Oom, M. d. M., Rebelo, R. and Rosa, G. M. (2013), Differential Effects of Dietary Protein on Early Life-History and Morphological Traits in Natterjack Toad (Epidalea Calamita) Tadpoles Reared in Captivity. Zoo Biol.. doi: 10.1002/zoo.21067
The production of high quality amphibian larvae through optimal diets is a critical component of amphibian conservation breeding programs. Larval period, survival, body weight and total length are frequently used as metrics of adequate nutrition. However, the effects of nutrition on tadpole and metamorph morphology are rarely tested in detail. In the present study, we analyzed the most common metrics and six other larval and post-metamorphic morphological traits in natterjack toads (Epidalea calamita) fed with three different commercial fish diets, varying in protein content (32.0%, 38.3%, and 46.2%). Our results suggest that early life-history (tadpole growth, development, and survival) and morphological traits of E. calamita tadpoles are differentially affected by the percentage of dietary protein. As protein content increased, tadpoles exhibited larger bodies along with shorter tail fins; however, with no significant differences in total length. Larval period was similar across treatments but mortality was lower in high-protein diet. At high-protein diets the metamorphs revealed significantly longer bodies, and wider heads and hind legs, but there was no significant difference in the average weight across all dietary treatments. Based on our results, feed containing 46.2% protein promotes growth, development and survival of E. calamita tadpoles better than either of the other two feeds tested. The use of other body measures beyond weight, tadpole total length, and snout-vent length in studies of amphibian nutrition in captivity may assist the selection of appropriate diets to optimize tadpole survival and metamorph fitness.

Lyke, M. M., Dubach, J. and Briggs, M. B. (2013), A molecular analysis of African lion (Panthera leo) mating structure and extra-group paternity in Etosha National Park. Molecular Ecology. doi: 10.1111/mec.12279
The recent incorporation of molecular methods into analyses of social and mating systems has provided evidence that mating patterns often differ from those predicted by group social organization. Based on field studies and paternity analyses at a limited number of sites, African lions are predicted to exhibit a strict within-pride mating system. Extra-group paternity has not been previously reported in African lions; however, observations of extra-group associations among lions inhabiting Etosha National Park in Namibia suggest deviation from the predicted within-pride mating pattern. We analysed variation in 14 microsatellite loci in a population of 164 African lions in Etosha National Park. Genetic analysis was coupled with demographic and observational data to examine pride structure, relatedness and extra-group paternity (EGP). EGP was found to occur in 57% of prides where paternity was analysed (n = 7), and the overall rate of EGP in this population was 41% (n = 34). Group sex ratio had a significant effect on the occurrence of EGP (P < 0.05), indicating that variation in pride-level social structure may explain intergroup variation in EGP. Prides with a lower male-to-female ratio were significantly more likely to experience EGP in this population. The results of this study challenge the current models of African lion mating systems and provide evidence that social structure may not reflect breeding structure in some social mammals.

Mueller, J. C., Partecke, J., Hatchwell, B. J., Gaston, K. J. and Evans, K. L. (2013), Candidate gene polymorphisms for behavioural adaptations during urbanization in blackbirds. Molecular Ecology. doi: 10.1111/mec.12288
Successful urban colonization by formerly rural species represents an ideal situation in which to study adaptation to novel environments. We address this issue using candidate genes for behavioural traits that are expected to play a role in such colonization events. We identified and genotyped 16 polymorphisms in candidate genes for circadian rhythms, harm avoidance and migratory and exploratory behaviour in 12 paired urban and rural populations of the blackbird Turdus merula across the Western Palaearctic. An exonic microsatellite in the SERT gene, a candidate gene for harm avoidance behaviour, exhibited a highly significant association with habitat type in an analysis conducted across all populations. Genetic divergence at this locus was consistent in 10 of the 12 population pairs; this contrasts with previously reported stochastic genetic divergence between these populations at random markers. Our results indicate that behavioural traits related to harm avoidance and associated with the SERT polymorphism experience selection pressures during most blackbird urbanization events. These events thus appear to be influenced by homogeneous adaptive processes in addition to previously reported demographic founder events.

Fulton, T. L., Norris, R. W., Graham, R. W., Semken, H. A. and Shapiro, B. (2013), Ancient DNA supports southern survival of Richardson’s collared lemming (Dicrostonyx richardsoni) during the last glacial maximum. Molecular Ecology. doi: 10.1111/mec.12267
Collared lemmings (genus Dicrostonyx) are circumpolar Arctic arvicoline rodents associated with tundra. However, during the last glacial maximum (LGM), Dicrostonyx lived along the southern ice margin of the Laurentide ice sheet in communities comprising both temperate and boreal species. To better understand these communities and the fate of these southern individuals, we compare mitochondrial cytochrome b sequence data from three LGM-age Dicrostonyx fossils from south of the Laurentide ice sheet to sequences from modern Dicrostonyx sampled from across their present-day range. We test whether the Dicrostonyx populations from LGM-age continental USA became extinct at the Pleistocene–Holocene transition ~11000 years ago or, alternatively, if they belong to an extant species whose habitat preferences can be used to infer the palaeoclimate along the glacial margin. Our results indicate that LGM-age Dicrostonyx from Iowa and South Dakota belong to Dicrostonyx richardsoni, which currently lives in a temperate tundra environment west of Hudson Bay, Canada. This suggests a palaeoclimate south of the Laurentide ice sheet that contains elements similar to the more temperate shrub tundra characteristic of extant D. richardsoni habitat, rather than the very cold, dry tundra of the Northern Arctic. While more data are required to determine whether or not the LGM southern population is ancestral to extant D. richardsoni, it seems most probable that the species survived the LGM in a southern refugium.

Letnic, M., Baker, L. and Nesbitt, B. (2013), Ecologically functional landscapes and the role of dingoes as trophic regulators in south-eastern Australia and other habitats. Ecological Management & Restoration. doi: 10.1111/emr.12035
Large carnivores can play a pivotal role in maintaining healthy, balanced ecosystems. By suppressing the abundances and hence impacts of herbivores and smaller predators, top predators can indirectly benefit the species consumed by herbivores and smaller predators. Restoring and maintaining the ecosystem services that large carnivores provide has been identified as a critical step required to sustain biodiversity and maintain functional, resilient ecosystems. Recent research has shown that Australia’s largest terrestrial predator, the Dingo (Canis lupus dingo), has strong effects on ecosystems in arid Australia and that these effects are beneficial for the conservation of small mammals and vegetation. Similarly, there is evidence from south-eastern Australia that dingoes suppress the abundance of macropods and red Fox (Vulpes vulpes). It is likely that dingoes in south-eastern Australia also generate strong indirect effects on the prey of foxes and macropods, as has been observed in the more arid parts of the continent. These direct and indirect effects of dingoes have the potential to be harnessed as passive tools to assist biodiversity conservation through the maintenance of ecologically functional dingo populations. However, research is required to better understand dingoes‘ indirect effects on ecosystems and the development of dingo management strategies that allow for both the preservation of dingoes and protection of livestock.

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