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D. P. Karabanov, Yu. V. Kodukhova, N. J. Mustafayev
Topmouth gudgeon Pseudorasbora parva (Cyprinidae)—A new species in the ichthyofauna of Azerbaijan
Russian Journal of Biological Invasions April 2013, Volume 4, Issue 2, pp 133-138

The paper presents the morphological and biological description of the topmouth gudgeon Pseudorasbora parva (Temminck et Schlegel, 1846) (Actinopterygii: Cyprinidae) from the water bodies of Azerbaijan. Low variability of morphological features in the studied populations is shown. The maximum age of the fish is 6+, the age of most adult fish is 3+ and 4+ and the immature fish are of age 0+ and 1+. The absolute fecundity ranges from 430 to 8690 eggs with an average value of 1940 eggs. It is known that the topmouth gudgeon has spread in the territory of western (Akstafa and Kazakh regions) and southern Azerbaijan (Lenkoran region).

B. Yu. Kassal, G. N. Sidorov
Russian Journal of Biological Invasions April 2013, Volume 4, Issue 2, pp 105-115
Distribution of the sable (Martes zibellina) and the pine marten (Martes martes) in Omsk oblast and biogeographic effects of their hybridization

Owing to range restoration of Martes zibellina and natural expansion of Martes martes to the southeast of Western Siberia, a zone of spontaneous hybridization of these species was formed. This process resulted in the appearance of kiduses, which affected the reproduction rates of both parent species. In the territory of Omsk oblast, the range boundaries of sable and pine marten with a particular area of cohabitation were established at the end of the 20th and the beginning of the 21st century. Hybridization of these species is an additional barrier to their deep penetration into the range of each other.

Quinn E. Fletcher, Manuelle Landry-Cuerrier, Stan Boutin, Andrew G. McAdam, John R. Speakman, Murray M. Humphries Reproductive timing and reliance on hoarded capital resources by lactating red squirrels
Oecologia July 2013

Successful reproduction in a seasonal environment can be accomplished with resources that are stored before use (“capital resources”) or resources that are used immediately (“income resources”). Research examining capital versus income resource usage during reproduction has primarily focused on assigning species to positions along a capital–income gradient. Here, we examine the causes and reproductive consequences of among and within-year variation in hoarded capital versus income resource usage by female North American red squirrels (Tamiasciurus hudsonicus) during mid-lactation in a highly seasonal environment. Among years, the proportion of feeding events that were on capital resources (PROPCAP) averaged 39 % during the yearly median mid-lactation periods, but ranged widely between 2 and 100 %. In years with earlier parturition dates, females primarily used hoarded capital resources during mid-lactation, whereas in years with later parturition dates, females primarily used income resources during mid-lactation. Within years, PROPCAP during mid-lactation tended to be greater in early-breeding females than in late-breeding females. Rates of water flux in females during mid-lactation provided further evidence that late-breeding females used more water-rich income resources. The proportion of litters that were partially or completely lost, and the litter mass that lactating females supported, was not influenced by the large among-year differences in hoarded capital resource usage. Red squirrels appear to delay reproduction following years with low cone production to time peak reproductive demands to be late enough to be supported by income resources that only become available later in the season. In conclusion, our results offer a rare example of the capacity of a food-hoarding mammal to support reproduction exploiting a wide range of capital and income resources.

Louis M. Herman, Adam A. Pack, Scott S. Spitz, Elia Y. K. Herman, Kathryn Rose, Siri Hakala, Mark H. Deakos
Humpback whale song: who sings?
Behavioral Ecology and Sociobiology July 2013

While on their winter breeding grounds, male humpback whales (Megaptera novaeangliae) produce long sequences of structured vocalizations called song, whose function within the mating system is still unresolved. Here we ask which males sing. Is it only those sexually mature, as typifies songbirds and some lekking ungulates in which vocalizations during the rut are restricted to mature males? Or do immature males join in the chorus? Using an underwater videogrammetric technique, we measured the body lengths of 87 humpback singers in the Hawaiian winter grounds. Applying length and sexual maturity relationships for North Pacific humpbacks as determined by biologists aboard twentieth century Japanese whaling vessels, we found that singer lengths ranged from 10.7 to 13.6 m, with 15 % of lengths indicative of probable sexual immaturity (length < 11.3 m, p [maturity] < 0.5). We interpret this broad participation of males as a lekking aggregation and the asynchronous singing chorus as an instance of by-product mutualism. The participation of many singers yields a heightened signal level that may attract more females to the singing area. Sexually mature males can benefit through access to more females. Immature males may gain deferred benefits through increased opportunities to learn and practice the social, behavioral, and acoustical skills and conventions of the winter grounds that they can apply usefully in later years.

Gry Aletta Bjørlykke, Bjørn Olav Kvamme, Arnt J. Raae, Bjorn Roth, Erik Slinde
Slaughter of Atlantic salmon (Salmo salar L.) in the presence of carbon monoxide
Fish Physiology and Biochemistry August 2013, Volume 39, Issue 4, pp 871-879

The different stunning methods for Atlantic salmon can still be improved with regard to animal welfare. Salmon exposed to carbon monoxide expressed no aversive reactions towards CO as such. CO exposed fish showed an earlier onset of rigour mortis and a faster decrease in muscle pH due to depletion of oxygen during the treatment. Exposure to CO did increase the level of cortisol compared to undisturbed control fish, but the increase was less than in the water only control group. Neuroglobin, a CO binding globin, was found in salmon brain and Saccus vasculosus, a richly vascularized sac connected to the fish brain. Binding of CO to neuroglobin during sedation might possibly improve animal welfare.

Golub, M. S. and Hogrefe, C. E. (2013), Predictors of hemoglobin variability in a population of weaning age (3- to 4-month old) rhesus monkeys. Am. J. Primatol.. doi: 10.1002/ajp.22176
Sources of variability in hemoglobin concentration in blood were examined in over 600 rhesus infants at the California National Primate Research Center who had complete blood counts (CBCs) conducted at 3–4 months of age. These infants were born and raised in outdoor social housing. Hemoglobin values ranged from 8.5 to 15.3 µg/dl with a mean and standard deviation of 12.2 ± 0.8 µg/dl. As expected, hemoglobin was strongly associated with the number of red blood cells (RBCs). Plasma protein concentration, an indicator of blood volume, was not a predictor. Associations with infant age, weight and sex, infant serum cortisol, dam’s reproductive history, and birth year, month and location were evaluated in regression analyses. Cage of origin, maternal age at delivery and infant weight were associated with hemoglobin concentrations. Unexpectedly, serum cortisol, determined at the same time as CBC samples were taken, was the strongest predictor of hemoglobin concentration. The basis, as well as the functional significance, of the variation in infant hemoglobin and its association with serum cortisol in this population of rhesus fed a nutritionally optimized diet and housed under standard conditions is relevant to the development of both nonhuman and human primate infants.

B. Willink, M. S. Palmer, T. Landberg, J. R. Vonesh, K. M. Warkentin Environmental context shapes immediate and cumulative costs of risk-induced early hatching
Evolutionary Ecology July 2013

In animals with complex life cycles, fitness trade-offs across life stages determine the optimal time for transitions between stages. If these trade-offs vary predictably, adaptive plasticity in the timing of life history transitions may evolve. For instance, embryos of many species are capable of accelerating hatching to escape from egg predation and other hazards, but for plasticity in hatching timing to be selectively maintained, early hatching must also entail costs, probably in subsequent life stages. However the post-hatching environment, which influences this cost, is variable in nature. We assessed how two elements of the post-hatching environment, predator species and age structure created by hatching age plasticity, affect costs of hatching early in red-eyed treefrogs, Agalychnis callidryas. Red-eyed treefrog embryos were induced to hatch at the onset of hatching competence or near the peak of spontaneous hatching and exposed to one of three insect predators in single or mixed hatching-age treatments. Age structure created by hatching-age plasticity did not affect tadpole survivorship or growth; however, the consequences of hatching timing depended on predator species and foraging mode. Tadpoles that were induced to hatch early experienced initially higher mortality rates only with the more actively foraging predator. Nonetheless, mortality costs of accelerated hatching were apparent with all predators once we factored in the longer duration of exposure that early hatchlings experience in nature. This study suggests that extended exposure of young larvae to predators may be a general cost of early hatching, explaining why spontaneous hatching occurs later in life across variable environmental contexts.

Ben T. Hirsch, Maria P. Tujague, Yamil E. Di Blanco, Mario S. Di Bitetti, Charles H. Janson, Comparing capuchins and coatis: causes and consequences of differing movement ecology in two sympatric mammals, Animal Behaviour, Available online 3 July 2013, ISSN 0003-3472, http://dx.doi.org/10.1016/j.anbehav.2013.05.023.
The mechanisms that shape animal movement decisions at the level of an individual or a group of animals can scale up to affect larger-scale ecological processes. Ecologists often use mechanistic animal movement models to understand these links, but animal movement models rarely connect empirically with an understanding of how animals actually decide to move around in their environment. To better understand this relationship, we compared the travel behaviour of two sympatric mammal species that have broadly similar diets: brown capuchin monkeys, Cebus apella nigritus, and ring-tailed coatis, Nasua nasua. According to most mechanistic animal movement models, species that exploit the same resources should show similar movement patterns. Although the fruit component of coati and capuchin diets is very similar, coatis primarily feed on invertebrates in the leaf litter or soil, while capuchins forage on invertebrate prey in the forest canopy. We found that these two species showed markedly different movement patterns: while capuchins typically travelled between fruit trees in relatively straight lines, coatis had significantly more tortuous daily travel paths and frequently visited the same fruit trees more than once per day. These circular coati travel paths would not be predicted by most foraging models. We posit that these differences in coati and capuchin movement patterns are driven by differences in arboreal and terrestrial travel costs, exploitation of fallen fruits and shifts in foraging behaviour over the course of the day. Because these seemingly small differences between the two species lead to major differences in movement behaviour, we posit that animal movement models need to better incorporate (1) travel costs, (2) both directed travel and random food search and (3) realistic diet models that include resources with different nutrient compositions.

Auersperg AMI, Kacelnik A, von Bayern AMP (2013) Explorative Learning and Functional Inferences on a Five-Step Means-Means-End Problem in Goffin’s Cockatoos (Cacatua goffini). PLoS ONE 8(7): e68979. doi:10.1371/journal.pone.0068979
To investigate cognitive operations underlying sequential problem solving, we confronted ten Goffin’s cockatoos with a baited box locked by five different inter-locking devices. Subjects were either naïve or had watched a conspecific demonstration, and either faced all devices at once or incrementally. One naïve subject solved the problem without demonstration and with all locks present within the first five sessions (each consisting of one trial of up to 20 minutes), while five others did so after social demonstrations or incremental experience. Performance was aided by species-specific traits including neophilia, a haptic modality and persistence. Most birds showed a ratchet-like progress, rarely failing to solve a stage once they had done it once. In most transfer tests subjects reacted flexibly and sensitively to alterations of the locks’ sequencing and functionality, as expected from the presence of predictive inferences about mechanical interactions between the locks.

Silva GSC, Roxo FF, Oliveira C (2013) Pareiorhina hyptiorhachis, a new catfish species from Rio Paraíba do Sul basin, southeastern Brazil (Siluriformes, Loricariidae). ZooKeys 315: 65–76. doi: 10.3897/zookeys.315.5307
Pareiorhina hyptiorhachis is described from Ribeirão Fernandes and Rio Pomba, Rio Paraíba do Sul basin, Brazil. The new species is distinguished from its congeners (Pareiorhina brachyrhyncha, Pareiorhina carrancas, Pareiorhina cepta, and Pareiorhina rudolphi) by the presence of a conspicuous ridge on the trunk posterior to the dorsal fin (postdorsal ridge), simple teeth, a completely naked abdomen, a round dorsal profile of the head, greater suborbital depth and greater head width. We discuss the distributional pattern of the new species and its congeners and hypothesize that headwater capture is responsible for the distribution of Pareiorhina species across different watersheds in southeastern of Brazil.

Zootaxa 3683 (4): 357–376 (5 Jul. 2013)
Overosaurus paradasorum gen. et sp. nov. , a new sauropod dinosaur (Titanosauria: Lithostrotia) from the Late Cretaceous of Neuquén, Patagonia, Argentina

A new lithostrotian sauropod, the small-sized Overosaurus paradasorum n. gen et sp. from the Anacleto Formation (Campanian, Late Cretaceous, Neuquén Group, Patagonia, Argentina) is here described. The specimen (MAU-Pv-CO-439)
consists of a fully articulated vertebral series from the 10th cervical to the 20th caudal vertebra, the last cervical ribs, several dorsal ribs in articulation with their respective vertebrae, the complete right ilium and fragments of the left ilium. Overosaurus paradasorum is diagnosed by a unique combination of characters that includes (1) posterior cervical vertebrae with long pre- and postzygapophyses that project beyond the anterior and posterior borders of the centrum, respectively, (2) postspinal lamina absent in all dorsal neural spines, (3) wide and massive 9th and 10th caudal centra that are slightly excavated laterally and have relatively flat ventral surfaces, (4) laminar projection on the posterior border of the second and third dorsal rib, (5) ilium proportionally shorter anteroposteriorly and taller dorsoventrally than in other lithostrotians, and (6) the preacetabular process of the ilium strongly deflected laterally and with a ventrolaterally tapering end. Analysis of the phylogenetic relationships of Overosaurus places it within the Aeolosaurini, as the sister taxon of a monophyletic group formed by Aeolosaurusrionegrinus, A. maximus, Gondwanatitan faustoi and Pitekunsaurus macayai. Overosaurus is a new representative of a highly diversified assemblage of Campanian lithostrotians from Patagonia that includes both Aeolosaurini and saltasaurids (e.g. Saltasaurus, Neuquensaurus)—this small new taxon falls within the low end of the size spectrum represented by these Late Cretaceous sauropods.

Zootaxa 3683 (4): 377–394 (5 Jul. 2013)
A small, new gerbil-mouse Eligmodontia (Rodentia: Cricetidae) from dunes at the coasts and deserts of north-central Chile: molecular, chromosomic, and morphological analyses

A small, new species of gerbil rodents of the genus Eligmodontia from the southwestern dunes of the Atacama Desert in
northern Chile is described; the genus had not been reported for this western lowland region. Our description is based on cytogenetic and molecular data, as well as cranial and external morphology. In order to support this hypothesis, we studied 27 specimens captured in Playa Los Choros (Coquimbo) and Copiapó (Atacama), comparing them with samples of all the extant species of the genus. Nineteen individuals consistently showed 2N=50, FN=48, with telocentric chromosomes and G-bands identical to those of the geographically northeastern E. hirtipes; these two groups were geographically separated by E. puerulus (2N=34, FN=48). The phylogenetic analysis of 56 Eligmodontia cytochrome-b gene sequences yielded a maximum-likelihood phylogenetic tree where the new species formed a divergent and well-supported clade within the genus, which was also confirmed by unweighted parsimony, minimum evolution, and Bayesian analyses. The new species has K2P genetic distances of 12.8% from the geographically distant E. hirtipes, and 10.3% from E. puerulus. Axes 1 and 2 of Principal Component Analysis based on 12 body and skull measurements clearly separated the new species, the latter having a smaller head+body length (70.6±3.4 mm, n=17) and lower weight (11.9±1.9 g, n=20). We provide strong evidence to recognize a distinct new western lineage within Eligmodontia genus, Eligmodontia dunaris sp. nov., for which we give a complete taxonomic description and a hypothetical biogeographic scenario. The new species should be considered endangered, due to its level of endemism, its low population numbers (which can be occasionally increased after a blooming desert) and its fragile dry habitat patchily distributed near the Atacama Desert.

Zootaxa 3683 (4): 427–438 (5 Jul. 2013)
Larval chondrocranium morphology of five species of Proceratophrys Miranda-Ribeiro (Amphibia; Anura; Odontophrynidae)

The chondrocranium and hyobranchial morphology are described for the tadpoles of five species of Proceratophrys
Miranda-Ribeiro. The chondrocranium of P. appendiculata, P. boiei, P. laticeps and P. tupinamba are very similar and can be distinguished from that of P. cristiceps by: 1) less developed processus muscularis; 2) thinner palatoquadrate; 3) broadest ethmoidal region; 4) longer cornua trabeculae; and 5) morphology f the suprarostral cartilages. A morphological variation among Proceratophrys boiei is described. It reveals the existence of at least three distinct evolutionary lineages under this name. A brief comparison with other cycloramphid species is also provided.

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