Abstract View

Zootaxa 3718 (2): 128–136 (3 Oct. 2013)
Classification and relationships of Assiculus and Assiculoides (Teleostei: Pseudochromidae)

The monotypic Australian pseudochromid fish genera Assiculus and Assiculoides had been previously included in the subfamily Pseudochrominae on the basis of symplesiomorphic characters. Osteological synapomorphies are identified in support of a closer relationship to the remaining pseudochromid subfamilies. Two synapomorphies (five or fewer infraorbital bones, haemal spine of preural vertebra 2 attached to centrum) diagnose a clade consisting of Assiculoides, Pseudoplesiopinae, Anisochrominae and Congrogadinae. Two additional synapomorphies (parhypural not separate from hypurals
1+2, total caudal-fin rays modally 27 or fewer) diagnose a more inclusive clade that also includes Assiculus. Two new
subfamilies are erected to reflect these relationships.

Andreas C. Bryhn, Henrik Ragnarsson Stabo, Jens Olsson, Modelling the biomass of functional groups of fish in an archipelago bay of the Baltic Sea, Ecological Modelling, Volume 269, 10 November 2013, Pages 86-97, ISSN 0304-3800, http://dx.doi.org/10.1016/j.ecolmodel.2013.08.015.
Fish biomass estimates in European coastal waters are necessary for several reasons, e.g., for meeting requirements in legislation and international agreements, for establishing sustainable outtakes of the resources, for developing management plans and for assessing the ecological and environmental status of coastal waters. This study estimated piscivorous and non-piscivorous fish biomass as well as total fish biomass in Kvädöfjärden Bay on the Swedish Baltic Sea coast using dynamic foodweb modelling. Weight-per-unit-effort data from the coastal fish monitoring program in the area together with a range of abiotic variables (including salinity and total phosphorus) were used as drivers for the CoastWeb model. To further refine the estimates of fish biomass, we complemented the model by using data from nearby areas on the ratio of piscivorous to non-piscivorous fish for those size classes not representatively sampled by the monitoring gear (fish<12cm). Piscivorous fish biomass in the area was estimated at 10–14 tonnes (4.6–6.5kg/ha), non-piscivorous fish biomass at 105–139 tonnes (47–62kg/ha) and the subsequent total fish biomass was estimated at 115–154 tonnes (52–69kg/ha). The estimated range of total fish biomass was comparable with findings from other investigations on the Swedish Baltic Sea coast which used a coarser methodology. The method presented in this paper can be used for making biomass estimates in other coastal waters where passive gears are used to monitor the local fish communities, and could thus serve a range of purposes for assessing the production and status of fish in coastal waters.

Taxonomic revision of the genus Carasobarbus Karaman, 1971 (Actinopterygii, Cyprinidae)
Kai Borkenhagen, Friedhelm Krupp
ZooKeys 339 (2013): 1-53
doi: 10.3897/zookeys.339.4903

Representatives of the fish genus Carasobarbus Karaman, 1971 (Actinopterygii: Cyprinidae) from the Middle East and North Africa were previously placed in 14 different genus-group taxa (Barbellion, Barbus, Barynotus, Capoeta, Carasobarbus, Cyclocheilichthys, Kosswigobarbus, Labeobarbus, Luciobarbus, Pseudotor, Puntius, Systomus, Tor and Varicorhinus). The generic assignment of several species changed frequently, necessitating a re-evaluation of their taxonomic status. In this study, the genus Carasobarbus is revised based on comparative morphological examinations of about 1300 preserved specimens from collections of several museums and freshly collected material. The species Carasobarbus apoensis, Carasobarbus canis, Carasobarbus chantrei, Carasobarbus exulatus, Carasobarbus fritschii, Carasobarbus harterti, Carasobarbus kosswigi, Carasobarbus luteus and Carasobarbus sublimus form a monophyletic group that shares the following combination of characters: medium-sized barbels with a smooth last unbranched dorsal-fin ray, nine or 10 branched dorsal-fin rays and six branched anal fin-rays; scales large, shield-shaped, with many parallel radii; the lateral line containing 25 to 39 scales; the pharyngeal teeth hooked, 2.3.5-5.3.2 or 2.3.4-4.3.2; one or two pairs of barbels. The species are described in detail, their taxonomic status is re-evaluated and an identification key is provided. A lectotype of Systomus luteus Heckel, 1843 is designated. Carasobarbus Karaman, 1971, Kosswigobarbus Karaman, 1971, and Pseudotor Karaman, 1971 are subjective synonyms, and acting as First Reviser we gave precedence to the name Carasobarbus.

Zootaxa 3718 (4): 367–377 (7 Oct. 2013)
A new fish species of the Genus Hapalogenys (Perciformes: Hapalogenyidae) from the Bay of Bengal, India

A new species of the genus Hapalogenys, Hapalogenys bengalensis sp. nov. is described from fourteen specimens col- lected from the Bay of Bengal coast. The species is distinct in having three longitudinal dark stripes; pelvic-fin tip almost reaching the base of first anal-fin spine when depressed; transverse scale rows above lateral line 7–8, below lateral line 19–20; gill rakers 18 (7 on lower limb and 11 on upper limb); posterior angle of jaw reaching vertical through anterior rim of eye. Genetic divergence (13.0–14.2%) and analysis of NJ tree shows that the new species is closely related to H. kishi- nouyei in the “Hapalogenys kishinouyei complex” with significant morphological difference from the other three species reported from the same complex.

Astrid V. Stronen, Paul C. Paquet, Perspectives on the conservation of wild hybrids, Biological Conservation, Volume 167, November 2013, Pages 390-395, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.09.004.
Hybridization processes are widespread throughout the taxonomic range and require conservation recognition. Science can help us understand hybridization processes but not whether and when we ought to conserve hybrids. Important questions include the role of humans in hybridization and the value we place on natural and human-induced hybrids concerning their ecological function. Certain hybrids resulting from human actions have replaced the ecological role of extirpated or extinct parent taxa and this ecological role should be preserved. Conservation policies must increasingly recognize populations of wild organisms that hybridize naturally within the context of their historical ecological role. Natural selection acts on individual organisms and the range of characteristics displayed by individual hybrids constitute raw material for evolution. Guidelines must consider the conservation value of individuals and the ethical aspects of removing hybrids for the purpose of conserving population genetic integrity. Conservation policies should focus on protecting the ecological role of taxa affected by hybridization. An informative example is North American canids (Canis), where body size, prey availability, and human landscape modifications may interact and impose local selective pressures. Gray wolves (Canis lupus) and eastern wolves (Canis lycaon or Canis lupus lycaon) or Great Lakes wolves appear to hybridize naturally within the context of their historical ecological role. In contrast, eastern coyotes (C. latrans) exhibit wolf ancestry and have partly replaced the ecological role of an extirpated parent taxa in parts of northeastern North America. The need for advancing conservation policies that reflect our current understanding of ecology and evolution is urgent.

Windels, S. K. (2013), Ear-tag loss rates in American beavers. Wildlife Society Bulletin. doi: 10.1002/wsb.343
External marking of American beavers (Castor canadensis) is essential to studies of population dynamics and behavior of individuals. Application of metal ear tags is a common method used to mark beavers but rates and causes of ear-tag loss have been insufficiently documented. I live-trapped and tagged 627 beavers in Voyageurs National Park, Minnesota, USA, from 2006 to 2012 with a single, uniquely numbered no. 3 monel ear tag in each ear. Beavers recaptured or recovered via live-trapping (n = 178), legal harvest outside of the park (n = 55), or death (n = 4) up to 6 years after initial release were inspected for tag loss. An additional 31 beavers were secondarily marked with radiotransmitters and used to test the assumption that loss of one ear tag was independent of loss of the other. Six percent (15 out of 237) of beavers lost a single ear tag. Overall probability of beavers losing a single ear tag was low (3.3%) and did not differ by sex, age class, or method of recapture–recovery. Tag loss was highest within 6 months of initial tagging, but probability of tag loss was not related to time between tagging and recovery up to 6 years after tagging. None of the radioed beavers lost both ear tags, supporting the assumption of independence of ear-tag loss among individual beavers. Ear-tag loss rates are sufficiently low that studies of American beavers that rely on mark–recapture methods do not need to account for bias from ear-tag loss. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Matchett, M. R., Breck, S. W. and Callon, J. (2013), Efficacy of electronet fencing for excluding coyotes: A case study for enhancing production of black-footed ferrets. Wildlife Society Bulletin. doi: 10.1002/wsb.348
Reducing coyote (Canis latrans) predation can be an important management objective. Here, we evaluated the efficacy of electronet fencing for excluding coyotes from focal areas on black tailed prairie dog (Cynomys ludovicianus) colonies, measured the effect of fencing on wild-born black-footed ferret (Mustela nigripes) kit survival, and modeled costs and benefits of fencing. From 27 July to 2 October 2010 in north-central Montana, USA, we erected and maintained 7.7 km of electronet that enclosed 108 ha on portions of 2 prairie dog colonies. We monitored 2 female ferrets and 6 kits inside exclosures and 3 females and 12 kits outside of exclosures. Percent of coyote sightings in the protected areas was 6 times less than expected during the exclosure period (42% pre-exclosure, 7% exclosure, 47% post-exclosure). We conclude that the electronet fencing was effective for dramatically decreasing coyote activity in focal areas where black-footed ferret litters were being raised. We found evidence that survival of kits living primarily in protected areas was 22% higher, but we qualify this finding because of low sample sizes and because our monitoring activity on the study site may have influenced coyote activity. We estimated one-time costs for fencing to be US$4,464/km and operation and/or maintenance costs for the 68 days of fence operation to be US$641/km. If fencing increased survival by 20–30%, then total cost per ferret kit not lost to coyote predation would range between US$5,400 and $3,600, or US$2,550 and $1,700 if fence set-up–take-down labor and use of an all-terrain vehicle were donated. Published 2013 is a U.S. Government work and is in the public domain in the USA.

Jaime E. Jiménez, Ramiro D. Crego, Gerardo E. Soto, Irán Román, Ricardo Rozzi, Pablo M. Vergara
Potential impact of the Alien American Mink (Neovison vison) on Magellanic woodpeckers (Campephilus magellanicus) in Navarino Island, Southern Chile
Biological Invasions October 2013

The American mink (Neovison vison) has been described as one of the worst invasive species in the northern hemisphere. Although some studies on the mink exist for the southern hemisphere, aside from impacts on marine and freshwater birds, its effect on other components of the biota is not well understood. Here, as a result of 3 different studies, we report evidence for the mink as a predator of the Magellanic woodpecker (Campephilus magellanicus). To our knowledge, these are the first evidences of predation on this charismatic and endemic woodpecker and indicate that mink might have a more widespread impact on forest birds than was initially suspected.

Tomasz Janiszewski, Piotr Minias, Zbigniew Wojciechowski
Timing of arrival at breeding grounds determines spatial patterns of productivity within the population of white stork (Ciconia ciconia)
Population Ecology October 2013

Early arrival at breeding grounds have important fitness consequences for migratory birds, both at individual and population level. The aim of this study was to investigate how the timing of arrival at the breeding territories affects the spatial patterns of reproductive success within a population of white storks (Ciconia ciconia). Data were gathered annually for ca. 200 pairs of storks breeding in central Poland between 1994 and 201Geostatistical analysis of data indicated that in years of delayed arrival of the population (measured by the first quartile arrival date), the reproductive output of storks was negatively autocorrelated, which indicated that there was a tendency for pairs of high breeding success to neighbour with pairs of low success. By contrast, in years when first storks returned in early dates to the breeding grounds, their reproductive success did not show any kind of spatial autocorrelation. These results suggest that delayed return of the first-arriving storks of the population may increase intensity of intra-specific competition to the level at which high-quality breeding pairs monopolize most of available resources at the expense of neighbouring low-quality pairs, which have lower reproductive success as a consequence. Such hypothesis was further supported with the analysis of nesting densities, showing that the late-arriving breeding pairs incurred greater fitness costs (or derived lower fitness benefits) while breeding in high densities comparatively to the early-arriving conspecifics.

K.M. Horback, L.J. Miller, S.A Kuczaj Ii, Personality assessment in African elephants (Loxodonta africana): Comparing the temporal stability of ethological coding versus trait rating, Applied Animal Behaviour Science, Available online 4 October 2013, ISSN 0168-1591, http://dx.doi.org/10.1016/j.applanim.2013.09.009.
The consistency of personality assessment was addressed in this study of 12 zoological African elephants living at the San Diego Zoo Safari Park in Escondido, CA, USA during the 2010 and 2011 summer seasons. Using 480h of observational behavior data, three personality traits were determined based on behavior events, with the most significant correlations being playful, curious, and sociable. During both summers, the animal care staff rated all elephants across 25 adjective items. Four rating-based personality traits were then clustered based on items with the most significant correlations (one-tailed rs >0.72, P<0.005): playful, observant, shy and confident. All seven personality traits correlated significantly from 2010 to 2011 for each individual elephant, demonstrating temporal stability. Additionally, the coded playful trait was correlated significantly to the rated trait playful, demonstrating construct validity and cross-method consistency. These results suggest that humans have the ability to discriminate zoo elephant personalities reliably and accurately. This, therefore, suggests that rating of zoo elephant personalities by caretakers with extensive knowledge of the species’ behavioral repertoire may be a valid proxy for long-term behavioral monitoring. Personality assessments may allow animal caretakers to identify appropriate roles for certain individuals (i.e., social compatibility, operant training, and transport to another facility), aid the individualization of environmental enrichment, and provide vital predictors of coping ability (i.e., stress response/resiliency).

Cyril C. Grueter, Martha M. Robbins, Felix Ndagijimana, Tara S. Stoinski, Possible Tool Use in a Mountain Gorilla, Behavioural Processes, Available online 3 October 2013, ISSN 0376-6357, http://dx.doi.org/10.1016/j.beproc.2013.09.006.
Here we report a description of putative tool use in wild mountain gorillas. At the Dian Fossey Gorilla Fund’s Karisoke Research Center in Volcanoes National Park (Rwanda), an adult female was observed using a bamboo culm as a ladder for her offspring. This is one of only a few documented cases of possible tool use in wild gorillas, although tool use behavior is commonly observed in captive gorillas. Although the behavior observed may have been incidental, the present report in combination with previous evidence suggests that tool use in gorillas occurs outside the context of food acquisition and may be directed at overcoming physical obstacles in complex rugged microhabitats such as bamboo forest and swamps.

Joshua M. Copus, Alice C. Gibb, A forceful upper jaw facilitates picking-based prey capture: biomechanics of feeding in a butterflyfish, Chaetodon trichrous, Zoology, Available online 4 October 2013, ISSN 0944-2006, http://dx.doi.org/10.1016/j.zool.2013.08.005.
Biomechanical models of feeding mechanisms elucidate how animals capture food in the wild, which, in turn, expands our understanding of their fundamental trophic niche. However, little attention has been given to modeling the protrusible upper jaw apparatus that characterizes many teleost species. We expanded existing biomechanical models to include upper jaw forces using a generalist butterflyfish, Chaetodon trichrous (Chaetodontidae) that produces substantial upper jaw protrusion when feeding on midwater and benthic prey. Laboratory feeding trials for C. trichrous were recorded using high-speed digital imaging; from these sequences we quantified feeding performance parameters to use as inputs for the biomechanical model. According to the model outputs, the upper jaw makes a substantial contribution to the overall forces produced during mouth closing in C. trichrous. Thus, biomechanical models that only consider lower jaw closing forces will underestimate total bite force for this and likely other teleost species. We also quantified and subsequently modeled feeding events for C. trichrous consuming prey from the water column versus picking attached prey from the substrate to investigate whether there is a functional trade-off between prey capture modes. We found that individuals of C. trichrous alter their feeding behavior when consuming different prey types by changing the timing and magnitude of upper and lower jaw movements and that this behavioral modification will affect the forces produced by the jaws during prey capture by dynamically altering the lever mechanics of the jaws. In fact, the slower, lower magnitude movements produced during picking-based prey capture should produce a more forceful bite, which will facilitate feeding on benthic attached prey items, such as corals. Similarities between butterflyfishes and other teleost lineages that also employ picking-based prey capture suggest that a suite of key behavioral and morphological innovations enhances feeding success for benthic attached prey items.

Lourdes Martínez Medina, Constantino Macías Garcia, Amira Flores Urbina, Javier Manjarrez, Alejandro Moyaho, Female vibration discourages male courtship behaviour in the Amarillo fish (Girardinichthys multiradiatus), Behavioural Processes, Available online 5 October 2013, ISSN 0376-6357, http://dx.doi.org/10.1016/j.beproc.2013.09.007.
Amarillo fish females (Girardinichthys multiradiatus) vibrate when conspecific males approach them; the reason behind this behaviour is unclear. Hypotheses are that females vibrate either to avoid aggression from males or to court them. We prevented females from vibrating by temporarily blocking their lateral line organs and eyes, on the assumption that they rely on these senses to detect approaching males. Females with the lateral line organs obstructed vibrated less frequently than females with the lateral line intact, indicating that the mechanosensory lateral line system is necessary for perceiving approaching males. Males displayed more courtship behaviour to sighted females with the lateral line organs obstructed than to sighted females with the lateral line intact. A general tendency indicated that the less the females vibrated the more the males courted them. These findings indicate that female vibration discourages male courtship behaviour.

Ronald Noë, Marion Laporte
Socio-spatial cognition in vervet monkeys
Animal Cognition October 2013

Safety in numbers is thought to be the principal advantage of living in groups for many species. The group can only provide protection against predators, however, when group cohesion is maintained. Vocalisations are used to monitor inter-individual distances, especially under conditions of poor visibility, but should be avoided in the presence of predators. Mentally tracking the movements of silent and invisible group members would allow animals foraging in dense vegetation to stay close to their group members while reducing the use of vocal contact. We tested the socio-spatial cognitive abilities of wild vervet monkeys (Chlorocebus pygerythrus) by comparing their reactions to plausible and implausible displacements of group members simulated by sound playbacks. Our methods are comparable to those used in studies of ‘object permanence’ and ‘invisible displacements’ of inanimate objects. Our results show that vervets can track the whereabouts of invisibly and silently moving group members, at least over short periods of time.

Da-Jiang Zheng, Lauren Foley, Asad Rehman, Alexander G. Ophir, Social recognition is context dependent in single male prairie voles, Animal Behaviour, Available online 7 October 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.09.015.
Single males might benefit from knowing the identity of neighbouring males when establishing and defending boundaries. Similarly, males should discriminate between individual females if this leads to more reproductive opportunities. Contextual social cues may alter the value of learning identity. Knowing the identity of competitors that intrude into an animal’s territory may be more salient than knowing the identity of individuals on whose territory an animal is trespassing. Hence, social and environmental context could affect social recognition in many ways. Here we test social recognition of socially monogamous single male prairie voles, Microtus ochrogaster. In experiment 1 we tested recognition of male or female conspecifics and found that males discriminated between different males but not between different females. In experiment 2 we asked whether recognition of males is influenced when males are tested in their own cage (familiar), in a clean cage (neutral) or in the home cage of another male (unfamiliar). Although focal males discriminated between male conspecifics in all three contexts, individual variation in recognition was lower when males were tested in their home cage (in the presence of familiar social cues) compared to when the context lacked social cues (neutral). Experiment 1 indicates that selective pressures may have operated to enhance male territorial behaviour and indiscriminate mate selection. Experiment 2 suggests that the presence of a conspecific cue heightens social recognition and that home-field advantages might extend to social cognition. Taken together, our results indicate social recognition depends on the social and possibly territorial context.

Erin E. Maxwell, Heinz Furrer, Marcelo R. Sánchez-Villagra. Exceptional fossil preservation demonstrates a new mode of axial skeleton elongation in early ray-finned fishes. Nature Communications, October 7, 2013. Doi: 10.1038/ncomms3570
Elongate body plans have evolved independently multiple times in vertebrates, and involve either an increase in the number or in the length of the vertebrae. Here, we describe a new mechanism of body elongation in saurichthyids, an extinct group of elongate early ray-finned fishes. The rare preservation of soft tissue in a specimen of Saurichthys curionii from the Middle Triassic (Ladinian) of Switzerland provides significant new information on the relationship between the musculature and the skeleton. This new fossil material shows that elongation in these fishes results from doubling the number of neural arch-like elements per myomeric segment. This unique way of generating an elongate body plan demonstrates the evolutionary lability of the vertebral column in non-teleostean fishes. The shape and arrangement of preserved myosepta suggest that S. curionii was not a highly flexible fish, in spite of the increase in the number of neural arch-like elements.

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