Abstract View

Zootaxa 3682 (3): 441–453 (28 Jun. 2013)
A revised taxonomy of crested newts in the Triturus karelinii group (Amphibia: Caudata: Salamandridae), with the description of a new species
B. WIELSTRA, S.N. LITVINCHUK, B. NAUMOV, N. TZANKOV & J.W. ARNTZEN

We present a taxonomic revision of the crested newt Triturus karelinii sensu lato. Based on the presence of discrete nuclear DNA gene pools, deep genetic divergence of mitochondrial and nuclear DNA, and no indication of gene flow, we interpret this taxon as comprising two species: one covering the southern Caspian Sea shore, the Caucasus and the Crimea, i.e. the eastern part of the total range and another covering northern Asiatic Turkey and western Asiatic Turkey plus the southeastern Balkan Peninsula, i.e. the central and western part of the total range. We acknowledge that the central/western species
should likely be further subdivided into a central and a western taxon, but we prefer to await a more detailed genetic analysis of the putative contact zone, positioned in northwestern Asiatic Turkey. The name T. karelinii (Strauch, 1870) applies to the eastern species as the type locality is positioned along the coast of the Gulf of Gorgan, Iran. The name T. arntzeni has been applied to the central/western species with Vrtovać, Serbia as the type locality. We show that not T. karelinii sensu lato but T. macedonicus occurs at Vrtovać. Hence, the name T. arntzeni Litvinchuk, Borkin, Džukić and Kalezić, 1999 (in Litvinchuk et al., 1999) is a junior synonym of T. macedonicus (Karaman, 1922) and should not be used for the central/western species. We propose the name T. ivanbureschi sp. nov. for the central/western species and provide a formal species description.

Beausoleil, R. A., Koehler, G. M., Maletzke, B. T., Kertson, B. N. and Wielgus, R. B. (2013), Research to regulation: Cougar social behavior as a guide for management. Wildlife Society Bulletin. doi: 10.1002/wsb.299
Cougar (Puma concolor) populations are a challenge to estimate because of low densities and the difficulty marking and monitoring individuals. As a result, their management is often based on imperfect data. Current strategies rely on a source–sink concept, which tends to result in spatially clumped harvest within management zones that are typically approximately 10,000 km2. Agencies often implement quotas within these zones and designate management objectives to reduce or maintain cougar populations. We propose an approach for cougar management founded on their behavior and social organization, designed to maintain an older age structure that should promote population stability. To achieve these objectives, hunter harvest would be administered within zones approximately 1,000 km2 in size to distribute harvest more evenly across the landscape. We also propose replacing the term “quota” with “harvest threshold” because quotas often connote a harvest target or goal rather than a threshold not to exceed. In Washington, USA, where the source–sink concept is implemented, research shows that high harvest rates may not accomplish the intended population reduction objectives due to immigration, resulting in an altered population age structure and social organization. We recommend a harvest strategy based on a population growth rate of 14% and a resident adult density of 1.7 cougars/100 km2 that represent probable average values for western populations of cougars. Our proposal offers managers an opportunity to preserve behavioral and demographic attributes of cougar populations, provide recreational harvest, and accomplish a variety of management objectives. We believe this science-based approach to cougar management is easy to implement, incurs few if any added costs, satisfies agency and stakeholder interests, assures professional credibility, and may be applied throughout their range in western North America.

Lesley Ricci, Cliff H. Summers, Earl T. Larson, Donald O’Malley, Richard H. Melloni Jr, Development of aggressive phenotypes in zebrafish: interactions of age, experience and social status, Animal Behaviour, Available online 27 June 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.04.011.
Aggression is important in the life history of most vertebrate species and influences ecological and social relationships by regulating the dynamics of territoriality, hierarchy, predation and resource utilization. The expression of aggressive behaviour develops as an individual ages and is often shaped by social experience. Even though the heritability of traits that yield dominant–subordinate relationships is high, strong environmental influences also shape the expression of these individual behaviours. In this study we present evidence for the first time of a necessary interplay between factors that generate behavioural phenotypic plasticity in zebrafish. Select presumptively genetic and environmental elements interacted developmentally to produce the behavioural phenotypes necessary for dominant–subordinate relationships in dyads. Aggressive and submissive acts increased in focus and intensity and were correlated with social rank during development, but decreased with duration of the paired interaction.

Engstedt, O., Engkvist, R. and Larsson, P. (2013), Elemental fingerprinting in otoliths reveals natal homing of anadromous Baltic Sea pike (Esox lucius L.). Ecology of Freshwater Fish. doi: 10.1111/eff.12082
We examined the element pattern in the otoliths of a migratory fish species that inhabit the coastal areas in the brackish of the Baltic Sea. The northern pike (Esox lucius) show migratory behaviour, spawning in streams and rivers and foraging in the sea. We examined spawning migration in four nearby streams in the south-west part of the Baltic. Otolith analysis by microPIXE revealed unique elemental patterns (Sr, Zn, Br, Co and Mn) for the juveniles in each of the different streams. The strontium signal in the otolith of the juveniles was used as an indicator of freshwater origin and the time spent in the stream. Adult pike in their migrating spawning phase were caught in each of the streams. The elemental composition in otoliths in their freshwater phase (using juvenile pike in the streams as references) was determined. A principal component analysis showed that the elemental fingerprint during the freshwater phase several years back in time was similar for the adult fish and for juveniles inhabiting the stream today. The results indicated natal homing of the adults to a specific stream, a conclusion that was strengthened by the fact that marked fish returned to spawn over consecutive years. Anadromous pike in the Baltic Sea may thus be divided in subpopulations. The results of the study may have implications for fishery management, as pike in the Baltic Sea cannot be seen as homogenous population.

Estramil, N., Bouton, N., Verzijden, M. N., Hofker, K., Riebel, K. and Slabbekoorn, H. (2013), Cichlids respond to conspecific sounds but females exhibit no phonotaxis without the presence of live males. Ecology of Freshwater Fish. doi: 10.1111/eff.12081
Many fish species are able to produce sounds, which are often associated with courtship. In an earlier study, we showed for the Lake Victoria cichlid Pundamilia nyererei that females prefer to associate with a male with sound over a male without sound. As a follow-up to this earlier finding, we here investigated whether playback of conspecific sounds is sufficient to attract females in the absence of a conspecific male. However, we did not find a phonotactic response for conspecific sounds in the absence of live males, using the same playback procedure as in our previous study. An additional playback test showed that both males and females discriminated between conspecific sounds and bursts of white noise. This suggests that the sounds may be recognised but that they seem only effective as attractant in the presence of visual and/or olfactory cues. These findings underline the multimodal complexity of fish communication and courtship and call for a more integrated study of the different modalities in future studies.

B.M. Waller, L. Warmelink, K. Liebal, J. Micheletta, K.E. Slocombe, Pseudoreplication: a widespread problem in primate communication research, Animal Behaviour, Available online 28 June 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.05.038.
Pseudoreplication (the pooling fallacy) is a widely acknowledged statistical error in the behavioural sciences. Taking a large number of data points from a small number of animals creates a false impression of a better representation of the population. Studies of communication may be particularly prone to artificially inflating the data set in this way, as the unit of interest (the facial expression, the call or the gesture) is a tempting unit of analysis. Primate communication studies (551) published in scientific journals from 1960 to 2008 were examined for the simplest form of pseudoreplication (taking more than one data point from each individual). Of the studies that used inferential statistics, 38% presented at least one case of pseudoreplicated data. An additional 16% did not provide enough information to rule out pseudoreplication. Generalized linear mixed models determined that one variable significantly increased the likelihood of pseudoreplication: using observational methods. Actual sample size (number of animals) and year of publication were not associated with pseudoreplication. The high prevalence of pseudoreplication in the primate communication research articles, and the fact that there has been no decline since key papers warned against pseudoreplication, demonstrates that the problem needs to be more actively addressed.

Lankau, H. E., E. M. Bayne, and C. S. Machtans. 2013. Ovenbird (Seiurus aurocapilla) territory placement near seismic lines is influenced by forest regeneration and conspecific density. Avian Conservation and Ecology 8(1):5.
http://dx.doi.org/10.5751/ACE-00596-080105

The boreal forest of western Canada is being dissected by seismic lines used for oil and gas exploration. The vast amount of edge being created is leading to concerns that core habitat will be reduced for forest interior species for extended periods of time. The Ovenbird (Seiurus aurocapilla) is a boreal songbird known to be sensitive to newly created seismic lines because it does not include newly cut lines within its territory. We examined multiple hypotheses to explain potential mechanisms causing this behavior by mapping Ovenbird territories near lines with varying states of vegetation regeneration. The best model to explain line exclusion behavior included the number of neighboring conspecifics, the amount of bare ground, leaf-litter depth, and canopy closure. Ovenbirds exclude recently cut seismic lines from their territories because of lack of protective cover (lower tree and shrub cover) and because of reduced food resources due to large areas of bare ground. Food reduction and perceived predation risk effects seem to be mitigated once leaf litter (depth and extent of cover) and woody vegetation cover are restored to forest interior levels. However, as conspecific density increases, lines are more likely to be used as landmarks to demarcate territorial boundaries, even when woody vegetation cover and leaf litter are restored. This behavior can reduce territory density near seismic lines by changing the spatial distribution of territories. Landmark effects are longer lasting than the effects from reduced food or perceived predation risk because canopy height and tree density take >40 years to recover to forest interior levels. Mitigation of seismic line impacts on Ovenbirds should focus on restoring forest cover as quickly as possible after line cutting.

Mark Hebblewhite
Consequences of ratio-dependent predation by wolves for elk population dynamics
Population Ecology June 2013

A growing number of studies suggest ratio-dependence may be common in many predator–prey systems, yet in large mammal systems, evidence is limited to wolves and their prey in Isle Royale and Yellowstone. More importantly, the consequences of ratio-dependent predation have not been empirically examined to understand the implications for prey. Wolves recolonized Banff National Park in the early 1980s, and recovery was correlated with significant elk declines. I used time-series data of wolf kill rates of elk, wolf and elk densities in winter from 1985–2007 to test for support for prey-, ratio-, or predator dependent functional and numeric responses of wolf killing rate to elk density. I then combined functional and numeric responses to estimate the total predation response to identify potential equilibrium states. Evidence suggests wolf predation on elk was best described by a type II ratio-dependent functional response and a type II numeric response that lead to inversely density-dependent predation rate on elk. Despite support for ratio-dependence, like other wolf-prey systems, there was considerable uncertainty amongst functional response models, especially at low prey densities. Consistent with predictions from ratio-dependent models, however, wolves contributed to elk population declines of over 80 % in our Banff system. Despite the statistical signature for ratio-dependence, the biological mechanism remains unknown and may be related to multi-prey dynamics in our system. Regardless, ratio-dependent models strike a parsimonious balance between theory and empiricism, and this study suggests that large mammal ecologists need to consider ratio-dependent models in predator–prey dynamics.

Grant Robert Bigg
Environmental confirmation of multiple ice age refugia for Pacific cod, Gadus macrocephalus
Evolutionary Ecology June 2013

The concept of species surviving through quaternary climatic extremes by retreating to glacial refugia, and then evolving genetically during re-population movements of the following interglacial, has been in the literature for over 40 years. Recently, advances in genetic analysis have enabled this concept to be validated and theories regarding population expansions and contractions to be built. For the major Northern Hemisphere species of cod, Gadus morhua (Atlantic cod) and Gadus macrocephalus (Pacific cod), genetic analysis has suggested retreat to separate refugia on both sides of their respective ocean basins during the last glacial period. Ecosystem niche modelling has previously confirmed that environmental conditions during the last glacial were compatible with the existence of these separate refugia for Atlantic cod. Here it is shown that such modelling also confirms a reduced core glacial distribution for G. macrocephalus, but probable refugia on either side of the Pacific. Existing mitochondrial DNA analyses suggest two separate glacial populations in the northwest Pacific, which modelling confirms, with predicted separate marine refugia in the land-locked Sea of Japan basin and the Sea of Okhotsk. Existing mitochondrial DNA for the northeast Pacific populations is less conclusive regarding whether there were one or two separate refugia off this coast, and their location. Using environmental niche models this study shows the glacial NE Pacific environment could support two marine refugia, one centred in the Aleutians/Gulf of Alaska and the other off British Columbia. The intervening Cordilleran Ice Sheet, and the glacially sub-aerial and ice-free Queen Charlotte Islands shelf, is hypothesised to have constrained exchange between glacial stocks either side of the Islands. The postulated southern marine refugium is off-shore from an established terrestrial refugium, suggesting greater dependence of species and ecosystems during environmental change. An earth system approach to evolutionary change could enhance understanding of past and future ecosystems.

Mukesh, Fernandes, M., Han, J. and Sathyakumar, S. (2013), Genetics driven interventions for ex situ conservation of red junglefowl (Gallus gallus murghi) populations in India. Zoo Biol.. doi: 10.1002/zoo.21081
Genetics driven interventions (GDI) are imperative for ex situ conservation to exhort long-term sustenance of small and isolated populations in captivity as they are more prone to an increased extinction risk due to inbreeding and genetic drift. We investigated constitutive genetic attributes of four captive Red Junglefowl (RJF) populations in India, to facilitate the prioritization of the birds to formulate an effective breeding action plan. All the four RJF populations were found to be evident of significant inbreeding but none of them had exhibited any signature of bottleneck footprints in the recent past. Bayesian cluster analysis revealed three distinct groups among the four captive RJF populations. Interestingly, birds of Kufri population were assigned together with Gopalpur as well as with Morni populations, indicating their shared genetic ancestry. Among the four populations, Morni population displayed the richest genetic attributes and was therefore presumed as a key source of genetic variation. Nine birds of Morni population were relatively pure (q-value >0.98) and carried about 50% of the total private alleles of Morni population. Thus, being the foremost reservoir of allelic diversity, these nine birds may be selected for launching alien alleles to other RJF populations to rescue their loss of genetic diversity arising from inbreeding.

Chadwick, C. L., Rees, P. A. and Stevens-Wood, B. (2013), Captive-Housed Male Cheetahs (Acinonyx jubatus soemmeringii) Form Naturalistic Coalitions: Measuring Associations and Calculating Chance Encounters. Zoo Biol.. doi: 10.1002/zoo.21085
Cheetahs are known to reproduce poorly in captivity and research suggests that the reasons for this are behavioral, rather than physiological. In the wild, male cheetahs remain in stable groups, or coalitions, throughout their lifetime. Appropriate social group housing is important in enhancing welfare and reproductive success in captivity and this study examined the effect of changes in social group composition on the behavior of four male cheetahs: two siblings and two half siblings. During the study, the cheetahs were housed both in pairs and as a group of four, before one male was relocated. The remaining cheetahs were then housed in a trio. Affiliative behaviors were frequently shown within pairs and overt aggression was seldom observed. Association indices were calculated for each cheetah pair and corrected for chance encounters based on data generated from a Monte Carlo simulation. The indices showed that two coalitions existed before the relocated male departed. Following the relocation of one of the half siblings, the remaining cheetahs appeared to form a coalition of three, as the indices of association between the unrelated male and the siblings increased and allogrooming between unrelated individuals was observed. The findings of this study indicate that natural social groupings of male cheetahs can be successfully replicated in captivity, which could potentially improve the chances of reproductive success when they are introduced to female cheetahs.

Eduardo Fernandez-Duque, Griëtte van der Heide
Dry Season Resources and Their Relationship with Owl Monkey (Aotus azarae) Feeding Behavior, Demography, and Life History
International Journal of Primatology June 2013

Limited food resource availability during yearly dry seasons can influence population dynamics and direct life-history evolution. We examined actual food production during two dry seasons and its relationship to feeding, life history, and demography in territorial, monogamous, and pair-living owl monkeys (Aotus azarae azarae). To quantify food availability in 16.25 ha of gallery forest in the Argentinean Chaco, we collected phenological data, from dry season fruit sources (N = 894), twice a month, during July and August of 2008 and 2009. At the same time, we collected feeding data from the four groups (N = 1448 h) inhabiting that forest portion. We also examined demographic data on births, natal dispersal, and group size. Our data show that owl monkeys occupy territories, and core areas, that produce food consistently, even during harsh times. Following the 2009 drought, less fruit was available than in 2008, but the 50 % core areas produced fruit amounts comparable to the 80 % territories. Owl monkeys showed dietary flexibility; fruits were the most frequent food item in 2008, whereas all groups increased their consumption of leaves in 2009. Infant production was lower in 2008 than after the drought of 2009. Interbirth intervals between the 2 yr were longer than the mean for the population, and more individuals dispersed in 2008 than in 2009. Our study suggests that owl monkeys occupy territories that provide similar amounts of reliable dry season foods within the core areas. Although access to these core areas may allow them to overcome severe dry seasons, our findings underscored the difficulties of understanding the potential causal relationships between ecological factors and demographic and life-history parameters.

Gin Morgan, Nate Kornell, Tamar Kornblum, Herbert S. Terrace
Retrospective and prospective metacognitive judgments in rhesus macaques (Macaca mulatta)
Animal Cognition June 2013

A growing body of research suggests that some non-human animals are capable of making accurate metacognitive judgments. In previous studies, non-human animals have made either retrospective or prospective judgments (about how they did on a test or how they will do on a test, respectively). These two types of judgments are dissociable in humans. The current study tested the abilities of two rhesus macaque monkeys to make both retrospective and prospective judgments about their performance on the same memory task. Both monkeys had been trained previously to make retrospective confidence judgments. Both monkeys successfully demonstrated transfer of retrospective metacognitive judgments to the new memory task. Furthermore, both monkeys transferred their retrospective judgments to the prospective task (one, immediately, and one, following the elimination of a response bias). This study is the first to demonstrate both retrospective and prospective monitoring abilities in the same monkeys and on the same task, suggesting a greater level of flexibility in animals’ metacognitive monitoring abilities than has been reported previously.

Mário Ferreira, Pedro Beja, Mediterranean amphibians and the loss of temporary ponds: Are there alternative breeding habitats?, Biological Conservation, Volume 165, September 2013, Pages 179-186, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.05.029.
In farmland landscapes, amphibians often breed in artificial water bodies, which may offset at least partly the loss of natural wetlands associated with agricultural intensification. It is possible, however, that artificial habitats provide conditions for a minor proportion of the regional species pool, benefiting just a few widespread generalists. We assessed these alternative views by documenting the decline of temporary ponds in a Mediterranean farmland landscape between 1991 and 2009, and by estimating the occupancy of natural (temporary ponds and streams) and artificial water bodies (farm ponds, irrigation channels and drainage ditches) by amphibians across the breeding season (February–June 2010). We used hierarchical Bayesian dynamic multi-species occupancy modelling to control for differences in detectability across species, sampling occasions and habitat types. Over two decades the farmland landscape lost 56% of its temporary ponds, of which 89.3% were destroyed through agricultural activities such as cultivation, conversion to permanent farm ponds, and drainage. The survival rate of ponds was lowest within an irrigated perimeter, and there was no positive effect of protection by a natural park. Estimated species richness per site was at least twice as high in temporary ponds as in the other habitat types. From the 10 amphibian species recorded, seven had the highest occupancy in temporary ponds, and were absent or occurred rarely in artificial habitats. Only a single generalist species was widespread in farm ponds and irrigation channels. The results suggest that artificial water bodies are unlikely to sustain populations of most amphibian species in Mediterranean intensive farmland. Conservation efforts should be directed at protecting the temporary ponds still remaining within the farmed landscape, and at restoring or creating new temporary ponds where these have been lost during the last decades.

Jordan A. Thomson, Andrew B. Cooper, Derek A. Burkholder, Michael R. Heithaus, Lawrence M. Dill, Correcting for heterogeneous availability bias in surveys of long-diving marine turtles, Biological Conservation, Volume 165, September 2013, Pages 154-161, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.06.005.
Effective conservation requires reliable data on the abundance and distribution of animals in space and time. During ship-based or aerial surveys for diving marine vertebrates such as sea turtles and marine mammals, a proportion of animals in a surveyed area will be missed because they are diving and out of view. While it is likely that dive and surface times vary with environmental conditions, such variation is rarely incorporated into survey-based research and its consequences for analyses of survey data are not well known. We quantified the effects of neglecting to account for variation in the dive-surfacing patterns of green turtles (Chelonia mydas) and loggerhead turtles (Caretta caretta) when analyzing boat-based survey data from a foraging ground in Western Australia. We found that analyses of turtle sightings data can be confounded by variation in the probability of turtles being at the surface where they are available for detection. For example, during the cold season in deeper areas in Shark Bay, green and loggerhead turtle density was underestimated by 45% and 21%, respectively, if extended dive times relative to population medians were not accounted for. These results have important implications for applications of survey data for a variety of taxa including other sea turtles, marine mammals and large sharks that are surveyed by boat or plane. Diving and depth use studies have much to contribute to the assessment and management of these groups, which include many species of conservation concern.

Orin J. Robinson, Nina H. Fefferman, Julie L. Lockwood, How to effectively manage invasive predators to protect their native prey, Biological Conservation, Volume 165, September 2013, Pages 146-153, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.06.001.
Invasive predators can have substantial effects on their native prey and often there is a need for rapid action to quell this impact. Conservation action is often employed on behalf of the native prey by means of predator removal or birth control. The decision to employ such actions is often based on the outcome of a population viability analysis (PVA) or similar method aimed at reducing the predator population. These models typically focus on one species and ignore the effects of that species’ interaction with others. Thus, there is inherently a disconnect between what is being managed (the predator population) and the desired outcome of the management (the persistence of a prey population). We built stage-based, stochastic matrix models of an invasive generalist predator and its native prey and coupled these using a functional response. We generated management recommendations based on the number of times the prey population persisted, and considered a range of life history types for predators and prey. We compared the results of our model to those generated by a traditional elasticity analysis commonly used in PVA. Recommendations from our model disagreed with those made by traditional elasticity most often when considering management of short-lived predators, and showed complete agreement between methods when considering long-lived predators. We illustrate that traditional PVA approaches to managing predators for the benefit of prey can provide inefficient control recommendations. Our coupled predator–prey model provides a flexible yet comprehensive approach to exploring management actions designed to benefit native prey species, including the option of ‘do nothing’.

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