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Tsai-Fu Chuang, Yuan-Hsiou Chang, A pilot study of using Artificial Neural Network on the climbing ability of Swinhoe’s Frog, Ecological Engineering, Volume 58, September 2013, Pages 255-261, ISSN 0925-8574, http://dx.doi.org/10.1016/j.ecoleng.2013.06.034.
Ecological engineering is the design of sustainable systems, consistent with ecological principles, which integrate human society with its natural environment for the benefit of both. In recent years, the threat to amphibian animals is becoming more and more serious. In particular, the loss of habitats caused by changes to the way land is used by human beings has hit amphibians particularly hard. Amphibians are known to be particularly vulnerable to human activities because they rely on both terrestrial and aquatic habitats for survival. With the increasing development of many areas in recent years, concrete structures are often installed along water bodies in order to increase the safety of local residents. The construction of concrete banks along rivers associated with human development has become a serious problem in Taiwan. Most ecosystems used by amphibians are lakes and stream banks, yet no related design solutions to accommodate the needs of amphibians. The need to develop the relevant design specification considering protecting the amphibian is imperative. Swinhoe’s Frog (Rana swinhoana), an endemic species in Taiwan, is tree frog widely distributed in altitude ranging under 2000 m. They like to live closed to brooks, streams and waterfall. In particular, their voice is a birdlike whistle calling day and night. Adult frog usually stand alone on rocks, banks or hide in vegetation near stream. Large eggs without pigment are deposited in small clumps under stones of slow running water (Yang, 1998). In this study, we use Artificial Neural Network to simulate the climbing ability of Swinhoe’s Frog. Artificial Neural Network (ANN) (Waller and Aiken, 1998) is a computing system that uses a large number of artificial neurons imitating natural neural ability to deal with an information network by computing system. The numerical results have show very good agreement with the experimental results. The results can serve as a reference for technicians involved in future ecological engineering designs of banks throughout the world.

Paul Miguet, Cédric Gaucherel, Vincent Bretagnolle, Breeding habitat selection of Skylarks varies with crop heterogeneity, time and spatial scale, and reveals spatial and temporal crop complementation, Ecological Modelling, Volume 266, 24 September 2013, Pages 10-18, ISSN 0304-3800, http://dx.doi.org/10.1016/j.ecolmodel.2013.06.029.
While many studies having investigated the effects of landscape complexity or heterogeneity on farmland biodiversity were focus on semi-natural habitats (e.g. forests, hedgerows), few have analyzed the consequences of local crop heterogeneity on species abundance. Here we quantify the effects of crop heterogeneity on the breeding habitat selection of the Skylark Alauda arvensis at spatial scales ranging from micro-habitat to landscape, in a western France farmland. We address the question of finding the processes behind the crop heterogeneity effect, usually never studied whatever the taxa. We first studied how crop composition at continuous spatial scales from within the breeding territory to the landscape (20-2000 m) affected Skylark habitat selection within a breeding season (i.e. the effect of each crop compared to the others), and how this selection changed with time. Second, we examined how the diversity of crops within areas of radius from 20 to 2000 m affected habitat selection by Skylarks. Third, we investigated for the processes behind the crop diversity, examining the detailed pattern of crop selection at the territory scale in presence of only two crops, to identify the synergetic effects of the simultaneous presence of two crops. Using an adequate spatial sampling of 200 m radius circular plots in which Skylarks positions were mapped twice the year, we observed a strong selection for grasslands, an intermediate selection for cereals and spring-sown crops (changing with scale and time), and an avoidance of oilseed rape. Selection for grasslands increased with the season, selection for spring-sown crops and oilseed rape was stable, while selection for cereals decreased but only at fine scale. Skylarks selected high crop diversity at the territory scale. Similarly, the synergetic effect of the presence of two crops was positive in most cases, and Skylarks preferred area with two crops rather than only one for some pairs of crops, indicative of landscape complementation (requirement for complementary resources located in different crop types). Our results suggest that smaller fields and crops well mixed in the landscape may benefit this farmland specialist, favouring the positive effects of the simultaneous presence of several crops. The study demonstrates the importance of considering simultaneously time and spatial scale dependencies, as well as the synergetic effects and the spatial arrangement of habitats in habitat selection studies, particularly in patchy dynamics environments such as farmlands.

Timothy M. Eppley, Malini Suchak, Jen Crick, Frans B. M. de Waal
Perseverance and food sharing among closely affiliated female chimpanzees
Primates July 2013

Chimpanzees (Pan troglodytes) have been frequently observed to share food with one another, with numerous hypotheses proposed to explain why. These often focus on reciprocity exchanges for social benefits (e.g., food for grooming, food for sex, affiliation, kinship, and dominance rank) as well as sharing based on begging and deterring harassment. Although previous studies have shown that each of these hypotheses has a viable basis, they have only examined situations in which males have preferential access to food whereby females are required to obtain the food from males. For example, studies on male chimpanzee food sharing take advantage of successful crop-raids and/or acquisitions of meat from hunting, situations that only leave females access to food controlled by male food possessors. This begs the question how and with whom might a female chimpanzee in sole possession of a high-quality food item choose to share? In two large captive groups of chimpanzees, we examined each of the hypotheses with female food possessors of a high-quality food item and compared these data to a previous study examining food transfers from male chimpanzees. Our results show that alpha females shared significantly more with closely affiliated females displaying perseverance, while kinship and dominance rank had no effect. This positive interaction between long-term affiliation and perseverance shows that individuals with whom the female possessor was significantly affiliated received more food while persevering more than those with neutral or avoidant relationships towards her. Furthermore, females with avoidant relationships persevered far less than others, suggesting that this strategy is not equally available to all individuals. In comparison to the mixed-sex trials, females chose to co-feed with other females more than was observed when the alpha male was sharing food. This research indicates that male and female chimpanzees (as possessors of a desired food item) share food in ways influenced by different factors and strategies.

Tilman C. Schneider, Rafał Kowalczyk, Max Köhler, Resting site selection by large herbivores – The case of European bison (Bison bonasus) in Białowieża Primeval Forest, Mammalian Biology – Zeitschrift für Säugetierkunde, Available online 26 July 2013, ISSN 1616-5047, http://dx.doi.org/10.1016/j.mambio.2013.06.002.
Resting site selection by European bison (Bison bonasus, L., 1758), the largest terrestrial mammal of Europe, was studied in the free-ranging population in Białowieża Primeval Forest (Poland) in 2009–2010. In total, 104 sites of 21 bison (both collared and uncollared) were analysed to determine the most important microhabitat characteristics selected by resting bison during summer and winter and to study the influence of supplementary feeding on resting behaviour of this herbivore. Resting sites were identified on the basis of GPS locations and activity records collected by GPS collars, as well as direct observations of bison, and were compared with control sites. Microhabitat selection by bison did not differ significantly between the sexes. During summer and winter, bison resting sites displayed a high tree density, low visibility and high complexity (structures providing cover). Summer resting sites were also characterised by a significantly lower abundance of blood-sucking insects and denser canopy than control sites. Winter resting sites showed a lower complexity and higher visibility than summer sites, and were less often located in mixed forest habitats. During winter, bison rested more frequently in forest below 50 years of age than in older forest. Resting sites of non-fed bison were more often located in young coniferous forests, were lower in visibility and situated closer to open areas than sites of bison using supplementary winter feeding, suggesting a trade-off between food and cover. The results indicate that European bison select their resting sites in areas of mosaic habitat structure providing cover from disturbances with access to profitable natural forage grounds.

Zootaxa 3693 (2): 152–162 (29 Jul. 2013)
Krobia petitella, a new species of cichlid fish from the Berbice River in Guyana (Teleostei: Cichlidae)

Krobia petitella, new species, is described from the Berbice River drainage of northeastern Guyana. It is distinguished from all other described species of Krobia (K. guianensis Regan, K. itanyi Puyo and K. xinguensis Kullander) as well as the closely related ‘Aequidens’ potaroensis and ‘A’. paloemeuensis by tubed scales of the upper lateral line extending caudally into a line bisecting the lateral band blotches posterior to the mid-lateral spot. Krobia petitella n. sp. can be further diagnosed by the anterior lateral band spots lying immediately ventral to the upper lateral line, instead of being separated from the upper lateral line by a complete row of scales in all other species. Additionally, K. petitella n. sp. possesses a unique lateral coloration pattern formed by the combination of six vertical bars and four lateral band spots (vs. K. itanyi 5 bars/3 or 4 spots, K. guianensis 5/5, K. xinguensis 7/6, ‘Aequidens’ potaroensis 6/6, ‘A’. paloemeuensis 5/5). The presence of Krobia petitella n. sp. in reaches of the Berbice River drainage in the Upper Demerara–Berbice region provides a novel locality for the genus in the Guianas and suggests the Berbice River has been isolated from the rest of nearby Guianese basins, particularly the Essequibo and the Corantijn.

Zootaxa 3693 (2): 182–188 (29 Jul. 2013)
Redescription of Phalotris labiomaculatus (Serpentes, Dipsadidae, Elapomorphini), with notes on the taxonomic boundaries within the nasutus group

Phalotris labiomaculatus Lema, 2002 was described based on a single specimen from Porto Franco, south of the Brazilian state of Maranhão, being rediscovered three years later in Mateiros, a municipality in the north of the state of Tocantins, attesting to its occurrence in the cerrado of both banks of the Tocantins River. The discovery of 28 new specimens from other localities during field expeditions (2009–2011) allowed a redescription of the species, adding new data on meristic and morpho-qualitative traits. These results enable a better diagnosis of intraspecific, ontogenetic and sexual variation,
consolidating its taxonomic relationships with other species belonging to the nasutus group. The distribution map of P. labiomaculatus, as well as an identification key to the species of the natusus group, are provided. The type-locality is fixed to the municipality of Porto Franco, state of Maranhão.

Zootaxa 3693 (2): 200–206 (29 Jul. 2013)
A new species of Lycengraulis Günther, 1868 (Clupeiformes: Engraulinae) from the Amazon basin, Brazil, with comments on Lycengraulis batesii (Günther, 1868)

A new species of Lycengraulis from the Amazon basin is described. Lycengraulis figueiredoi can be distinguished from L. grossidens by a short upper maxilla, its posterior margin not reaching the lower maxilla joint (vs. upper maxilla longer, its posterior margin reaching to or a little past of mandible joint). Lycengraulis figueiredoi can be distinguished also from L. poeyi by 26 to 31 anal-fin rays (vs. 21 to 23 anal-fin rays) and by 44 to 46 vertebrae (vs. 42 vertebrae), and from L. batesii by having the anal-fin origin at vertical through base of second to fifth dorsal-fin ray (vs. anal-fin origin at vertical through base of sixth to 10th dorsal-fin ray) and by 17-21 gill rakers on the lower branch of first gill arch (vs. 12–15 gill rakers on the lower branch of first gill arch). The new species occurs in the rio Purus, Negro, Trombetas and Solimões, in the Amazon basin, Brazil.

Grant Harris, Ryan M. Nielson, Todd Rinaldi, Thomas Lohuis
Effects of winter recreation on northern ungulates with focus on moose (Alces alces) and snowmobiles
European Journal of Wildlife Research July 2013

Winter recreation can displace ungulates to poor habitats, which may raise their energy expenditure and lower individual survivorship, causing population declines. Winter recreation could be benign, however, if animals habituate. Moreover, recreation creates trails. Traveling on them could reduce energy expenditure, thereby increasing ungulate survivorship and generating population benefits. Balancing recreation use with wildlife stewardship requires identifying when these effects occur. This task would be simpler if guidelines existed to inform assessments. We developed and tested such guidelines using two approaches. First, we synthesized literature describing the effects of winter recreation—motorized and nonmotorized—on northern ungulates. This synthesis enabled formulating six guidelines, while exposing two requiring further attention (ungulate habituation and displacement). Second, we tested these two guidelines and evaluated the others by quantifying the behavioral responses of moose to snowmobiles, in two areas of south-central Alaska, differing by snowmobile predictability. For each location, we modeled moose preferences during the snowmobile period using different combinations of eight variables—static (elevation and slope), biotic (habitat and cover), and anthropogenic (distance to roads, railroads, snowmobile trails, and trail density). We identified the model with the most support and used it to estimate parameter coefficients for pre- and post-recreation periods. Changes in coefficients between periods indicated snowmobile effects on moose. Overall, we produced and evaluated six guidelines describing when winter recreation is potentially detrimental to ungulates as follows: (1) when unpredictable, spanning large areas, long in duration, large spatial footprint, nonmotorized, and when animals are displaced to poor quality habitats.

Emma J. Knott, Nils Bunnefeld, Djuro Huber, Slaven Reljić, Vesna Kereži, E. J. Milner-Gulland
The potential impacts of changes in bear hunting policy for hunting organisations in Croatia
European Journal of Wildlife Research July 2013

The brown bear (Ursus arctos) in Croatia is currently being managed through trophy hunting, with quotas allocated to local hunting organisations. Human–bear conflict is present at a low level, but any losses are compensated by the hunting organisations that benefit from bear hunting. Attitudes towards bears are generally positive, and the bear population appears stable, or even increasing. Croatia’s current bear hunting policy relies upon both the ecological sustainability of the quotas and the economic sustainability of the hunting organisations. To address the first of these pillars of current policy, we used a two-sex matrix model of the bear population to investigate the biological sustainability of current hunting levels. The model suggests that if the annual allocated quota were fully realised, the population would suffer a considerable decrease over 10 years. A likely explanation for the mismatch between this result and the observed stability of the population is that the bear population size is underestimated. To address the second pillar, we quantified the current structure, costs and benefits of bear hunting to hunting organisations through an interview survey with hunting managers. We found that bear hunting is a substantial component of hunting organisations‘ income, supporting the other activities of the organisation. Croatia’s recent accession to the EU will require changes in their bear management system, potentially stopping bear trophy hunting. Therefore, we assessed the changes in hunting organisations‘ budgets in the absence of bear hunting. Our results demonstrate that a loss of bear trophy hunting would result in a substantial loss of income to the hunting organisations. Moving bear hunting and compensation mechanisms from local management and responsibility to a more centralised system without trophy hunting, as suggested by EU legislation, will lead to considerable uncertainties. These include how to make centralised decisions on population targets and offtake levels for population control, given the uncertainty around population estimates, and on compensation payments given the loss of the current system which relies heavily on local income from trophy hunting, local relationships and informal monetary and non-monetary compensation.

DiLeo, M. F., Rouse, J. D., Dávila, J. A. and Lougheed, S. C. (2013), The influence of landscape on gene flow in the eastern massasauga rattlesnake (Sistrurus c. catenatus): insight from computer simulations. Molecular Ecology. doi: 10.1111/mec.12411
Understanding how gene flow shapes contemporary population structure requires the explicit consideration of landscape composition and configuration. New landscape genetic approaches allow us to link such heterogeneity to gene flow within and among populations. However, the attribution of cause is difficult when landscape features are spatially correlated, or when genetic patterns reflect past events. We use spatial Bayesian clustering and landscape resistance analysis to identify the landscape features that influence gene flow across two regional populations of the eastern massasauga rattlesnake, Sistrurus c. catenatus. Based on spatially explicit simulations, we inferred how habitat distribution modulates gene flow and attempted to disentangle the effects of spatially confounded landscape features. We found genetic clustering across one regional landscape but not the other, and also local differences in the effect of landscape on gene flow. Beyond the effects of isolation-by-distance, water bodies appear to underlie genetic differentiation among individuals in one regional population. Significant effects of roads were additionally detected locally, but these effects are possibly confounded with the signal of water bodies. In contrast, we found no signal of isolation-by-distance or landscape effects on genetic structure in the other regional population. Our simulations imply that these local differences have arisen as a result of differences in population density or tendencies for juvenile rather than adult dispersal. Importantly, our simulations also demonstrate that the ability to detect the consequences of contemporary anthropogenic landscape features (e.g. roads) on gene flow may be compromised when long-standing natural features (e.g. water bodies) co-exist on the landscape.

Alice Auersperg, Birgit Szabo, Auguste von Bayern, Thomas Bugnyar: Object Permanence in Goffin Cockatoos (Cacatua goffini). Journal of Comparative Psychology.
DOI: http://psycnet.apa.org/doi/10.1037/a0033272

The ability to represent hidden objects plays an important role in the survival of many species. In order to provide an inclusive synopsis of the current benchmark tasks used to test object permanence in animals for a psittacine representative, we tested eight Goffin cockatoos (Cacatua goffini) on Stages 3–6 of Piagetian object permanence as well as derivations of spatial transposition, rotation, and translocation tasks. Subjects instantly solved visible displacement 3b and 4a but showed an extended plateau for solving Stage 5a at a very late age (10 months). Subjects readily solved most invisible displacement tasks including double hidings and four angles (90°, 180°, 270°, and 360°) of rotation and translocations at high performance levels, although Piagetian Stage 6 invisible displacement tasks caused more difficulties for the animals than transposition, rotations, and translocation tasks.

Dana Thiele, Emilienne Razafimahatratra, Andreas Hapke, Discrepant partitioning of genetic diversity in mouse lemurs and dwarf lemurs – biological reality or taxonomic bias?, Molecular Phylogenetics and Evolution, Available online 27 July 2013, ISSN 1055-7903, http://dx.doi.org/10.1016/j.ympev.2013.07.019.
Unequal degrees of taxonomic subdivision can pose problems for research that relies on cross-taxon comparisons of biogeographic patterns. Numerous species of lemurs have been described in recent years. These descriptions were unevenly distributed over the genera of lemurs as exemplified by the closely related mouse lemurs (Microcebus spp.) and dwarf lemurs (Cheirogaleus spp.). According to previous studies, these genera display striking differences such as many versus few species, small versus large distributions, and small versus large mitochondrial divergence within and between species. We questioned if these differences reflect the biological reality or a biased taxonomic subdivision, which might be partially due to relatively small amounts of available genetic data from dwarf lemurs. We complemented existing datasets with genetic data from 51 dwarf lemurs from nine sites in southern Madagascar. We analyzed the mitochondrial cytb gene and the nuclear loci adora3, fiba, and vWF. Based on a comparison of mitochondrial genetic data from both genera, we delineated eight hypothetical subgroups within two recognized Cheirogaleus species. We used mitochondrial and nuclear data to reconstruct species trees and to estimate divergence times between Microcebus species and Cheirogaleus subgroups. We further performed Bayesian species delimitations based on nuclear sequence data from Cheirogaleus subgroups. Strong signals in mitochondrial and nuclear data indicate the existence of deeply divergent, distinct groups within recognized Cheirogaleus species. Based on several lines of evidence, we conclude that the species diversity in Cheirogaleus has been underestimated so far. We delineate six species among the eight subgroups and provide a formal description for one new Cheirogaleus species.

Zootaxa 3693 (3): 387–394 (30 Jul. 2013)
A new species of Microcaecilia (Amphibia: Gymnophiona: Siphonopidae) from the Guianan region of Brazil

We describe a new species of Microcaecilia from the Guianan region of Brazil, based on a series of eight specimens from the states of Pará and Amazonas. Microcaecilia marvaleewakeae sp. nov. is very similar to M. taylori, but differs from it in having more primary annuli, more secondary grooves, and more secondary grooves that completely encircle the body. The new species also seems to have a relatively shorter and thinner head than M. taylori, but additional specimens of the new species are necessary to check this. A brief discussion of the taxonomy of M. taylori is presented.

McCabe, G. M., Fernández, D. and Ehardt, C. L. (2013), Ecology of reproduction in Sanje mangabeys (Cercocebus sanjei): Dietary strategies and energetic condition during a high fruit period. Am. J. Primatol.. doi: 10.1002/ajp.22182
The ability to increase energy storage when food is abundant for later use during late gestation and early lactation is often considered the primary benefit of the capital breeding strategy (clustering conceptions during high food periods, HFP) that promotes reproductive success among females living in unpredictable environments. Capital breeding, however, may also enable preconceptive females to increase hormone production for ovulation, which has been linked to energetic condition in capital breeders, and/or allow females entering the subsequent HFP to increase their energetic condition in order to continue nursing unweaned infants. Here, we investigate whether capital breeding provides these additional benefits in 16 female Sanje mangabeys (Cercocebus sanjei) and determine the dietary strategies used to increase energetic condition (measured by urinary C-peptide: UCP) during the HFP. Fecal estradiol (fE2) and UCP were negatively correlated with number of cycles before conception (r = −0.591, r = −0.646, P < 0.01) and were highest in conceptive cycles. Both peri-conceptive (preconception and early gestation) and non-peri-conceptive (lactation) females increased energetic condition over the HFP (r = 0.612, r = 0.583, P < 0.001) by increasing dietary fat (r = 0.619, r = 0.703, P < 0.001) and, for non-peri-conceptive females, protein (r = 0.437, P < 0.001). Feeding intake rate (FIR) and time spent foraging and feeding did not change over the HFP; however, non-peri-conceptive females exhibited a faster FIR compared to peri-conceptive females (t = −2.324, P < 0.05), consuming almost twice as much food per unit time. The results of this study confirm that Sanje mangabeys benefit in multiple phases of the reproductive cycle by using capital breeding, which may explain how this strategy promotes female reproductive success.

Yamauchi, A. and Namba, T. (2013), Dynamics of predator and modular prey: effects of module consumption on stability of prey–predator system. Oikos. doi: 10.1111/j.1600-0706.2013.00438.x
In traditional models of predator–prey population dynamics, it is usually assumed that consumed prey are immediately removed from the population. However, in plant–herbivore interactions, damaged plants are generally alive after attacks by herbivores. This can result in successive or simultaneous attacks by multiple predators on a single prey item (here, the term prey is expanded to include plants). We constructed a mathematical model with two time scales, taking into account predation processes within a generation, considering post-predation survival and the modularity of prey. We assumed that a prey item can be divided into modules and that it can be fed on by multiple predators or parasitized by multiple parasites at the same time. The model includes two essential factors: the modularity of prey for predators (n) and the detaching/attaching ratio of predators to prey (ε). Based on the formulae, we revealed a general property of realistic dynamics in plant–herbivore and host–parasite interactions. The analysis showed that the model could be approximated by models with the type I, type II or Beddington–DeAngelis functional responses by taking appropriate limits to the situations. When modularity is low or the detaching/attaching ratio is high, population dynamics tend to be stabilized. These stabilizing effects may be related to interference competition among predator individuals or increases in free prey modules and free predator individuals. In the limit of high modularity, the ratio of the attached prey modules to the total prey modules becomes negligible and the dynamics tend to be destabilized. However, if quantity and quality of prey modules are negatively correlated, the equilibrium is likely to be stabilized at high modularity as long as it remains feasible. These results suggest that considering post-predation survival and modularity of prey is crucial to understand predator–prey interactions.

Su-Jen Roberts, Marina Cords
Group size but not dominance rank predicts the probability of conception in a frugivorous primate
Behavioral Ecology and Sociobiology July 2013

In social mammals, within-group competition for food can drive variation in female fitness. Frugivores may face particularly strong competition because they use patchily distributed usurpable resources. Dominance rank and group size influence how a female experiences within-group competition. Both are predicted to affect access to food and, thus, reproductive success. We used 15 years of behavioral, demographic, and reproductive data from wild frugivorous blue monkeys to examine effects of rank and group size on the probability that a female conceived. We used generalized linear mixed models, controlling for potentially confounding maternal and environmental factors. Blue monkey females compete aggressively and disproportionately for fruits and exhibit linear dominance hierarchies, but neither rank index we tested significantly predicted the probability of conception. Although earlier studies found that group size effects on activity budgets were minimal, we found that group size had a quadratic relationship with the probability of conception, which peaked at around 31 members. The lack of a rank effect may reflect behavioral strategies (e.g., switching resources, spreading out during feeding, using cheek pouches) that minimize the strength of within-group competition, thus facilitating group-level cooperation in between-group contests. The significant quadratic effect of group size on reproduction may occur if individuals in small groups do not obtain the full benefits of group living (e.g., predator avoidance, increased foraging success, communal care for offspring) and those in large groups experience a lower quality diet or constrained feeding time. Ultimately, measures of reproduction are preferable to behavioral proxies for accurately assessing within-group competition.

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