Abstract View

Zootaxa 3619 (3): 369–382 (28 Feb. 2013)
Phylogenetic placement of the European sand gobies in Gobionellidae and characterization of gobionellid lineages (Gobiiformes: Gobioidei)

The Mediterranean, northeastern Atlantic, and inland freshwaters of Europe and the Ponto-Caspian region host a distinct fauna of gobiiform fishes, including the sand gobies (Pomatoschistus Gill and related genera), all of which have been classified in the most diverse goby group, the family Gobiidae. Recent molecular phylogenetic analyses have suggested that the sand gobies are not gobiids, and are instead part of their sister clade Gobionellidae (Thacker and Roje 2011). Phylogenetic analysis of Pomatoschistus in the context of both gobiid and gobionellid taxa indicates that Pomatoschistus is part of Gobionellidae, specifically the Mugilogobius lineage. Gobionellidae includes 93 genera, which are arrayed into four lineages (Stenogobius, Mugilogobius, Periophthalmus and Northern Pacific). These lineages exhibit variation in characters of the jaw and suspensorium, including the shapes and relative positions of the palatine, quadrate, and ectopterygoid.
The observations of the palatopterygoid complex in Gobionellidae of Harrison (1989) and Larson (2001) are supported and augmented. Gobionellidae generally exhibit suspensoria that are overall more elongated and gracile than those of gobiids: the palatine/ectopterygoid pair features a very short (Periophthalmus lineage) or elongate, pointed palatine (Mugilogobius, Northern Pacific, and Stenogobius lineages), with a relatively slender ectopterygoid and a short quadrate articulation. In Gobiidae, the palatine extends about halfway along the length of the ectopterygoid, and the ectopterygoid generally features a large, flat articulation with the quadrate. Suspensoria of Pomatoschistus and relatives are similar to those of other taxa in the Mugilogobius lineage. Placement of Pomatoschistus and relatives in Gobionellidae rather than Gobiidae is significant in that it indicates that sand gobies are not closely related to other European gobies, and has implications for any comparative evolutionary or biogeographic studies.

Woc-Colburn, A. M., Murray, S., Lock, J., Dragoo, J. W., Guglielmo, D. and Maldonado, J. E. (2013), A Minimally Invasive Method for Gender Determination in the Prehensile-Tailed Porcupine (Coendou prehensilis). Zoo Biol.. doi: 10.1002/zoo.21063
Prehensile-tailed porcupines (Coendou prehensilis), like other rodents, lack external sexual traits, making it difficult to non-invasively determine their gender. By exploiting genetic differences between the X and the Y chromosome, we developed a simple genetic test to determine the gender of Coendous from shed quills. We Sanger sequenced a short portion (195 bp) of the zinc finger protein gene of known male (XY) Coendous to identify positions that are polymorphic between the X and Y chromosomes at this locus. By directly sequencing this fragment, we were able to correctly determine (confirmed via anatomical sexing) the gender of male and female Coendous by the presences or absence of polymorphisms in the resulting chromatograms. This assay is simple, quick and is applicable to other porcupine species.

Herrmann, E. A., Herrin, K. V., Gleen, W., Davies, P., Stapley, R., Stebbings, V., Wiszniewski, J., Spindler, R., Faichney, G. J. and Chaves, A. V. (2013), Partial Replacement of an Artificial Nectar Diet With Native Browse for Feather-Tail Gliders (Acrobates pygmaeus) in Captivity. Zoo Biol.. doi: 10.1002/zoo.21064
Captive-bred feather-tail gliders (Acrobates pygmaeus) housed at Taronga Zoo have had a long history of eye cholesterol plaques that may be associated with a largely sugar-based diet such as artificial nectar. The gliders also have prolonged periods of reduced activity when they are not visible in exhibits. This may be due to the ad libitum supply of an energy rich feed and reduced need to forage. This study examined behavioral and physiological changes associated with supplementing the high sugar-based diet with two species of native browse. The experiment was conducted over two consecutive periods of 3 weeks and consisted of two treatment groups: one group was offered the artificial nectar only, while the other group was offered the artificial nectar supplemented with a variety of native flowers. Live weight was recorded weekly. There was no change (P > 0.10) in artificial nectar intake with the supplementation of native browse in the diet. Blood metabolites (cholesterol, triglycerides, glucose) tested for the two groups had no differences (P > 0.10) between treatments. Upon examination, there were no signs of tooth decay or cholesterol plaques in all animals throughout the experiment. Feed intake and behavior were recorded via sensor cameras. There was an increase (P < 0.05) in the daily foraging activity of gliders supplemented with native flowers compared to gliders fed the artificial nectar alone. In conclusion, supplementing to provide a more native diet to A. pygmaeus enhanced their natural foraging behavior, suggesting that it may result in long-term improvements in their health.

The New Zealand falcon and wind farms: a risk assessment framework
R Seaton, LP Barea
New Zealand Journal of Zoology
Vol. 40, Iss. 1, 2013
Internationally, birds of prey are often reported as being relatively prone to collision with wind turbines in comparison to other groups of birds. However, as yet it is unclear to what extent New Zealand’s only endemic bird of prey, the New Zealand falcon (Falco novaeseelandiae), is at risk. In this paper we summarise the potential for wind farms to impact New Zealand falcon, evaluate the efficacy of a range of risk assessment and post-consent monitoring practices, and present options for mitigating and/or offsetting any residual effects. We conclude that the lack of knowledge on the effects of wind farms on New Zealand falcon is the result of inconsistency in the assessment methods thus far employed and the absence of a coordinated approach to monitoring methods and the dissemination of results. To remedy this we present a risk assessment framework that, if adopted, will provide the information necessary to ensure alternative energy targets can be met without compromising the conservation of this threatened species.

Avian collisions at two wind farms in Tasmania, Australia: taxonomic and ecological characteristics of colliders versus non-colliders
CL Hull, EM Stark, S Peruzzo, CC Sims
New Zealand Journal of Zoology
Vol. 40, Iss. 1, 2013
Data obtained during carcass and bird utilisation surveys conducted over an approximately 10-year period at two wind farms in northwest Tasmania (Bluff Point Wind Farm [BPWF] and Studland Bay Wind Farm [SBWF]) were compared. Of the species present onsite only 21% at the BPWF and 18% at the SBWF were found to collide with turbines, indicating that presence onsite was a poor indicator of collision risk. Furthermore, there was a poor relationship between abundance onsite and collisions with turbines. A classification and regression tree classified species into the groups that collided or did not collide, based on two classifiers. Specific families/superfamilies and foraging strategies/zones were associated with collision risk and indicated that particular morphological, ecological and behavioural factors were associated with a species‘ vulnerability to colliding with wind turbines. Future studies should investigate whether the patterns found at these sites are consistent across other habitats and sites.

Sanders, D., Sutter, L., van Veen, F. J. F. (2013), The loss of indirect interactions leads to cascading extinctions of carnivores. Ecology Letters. doi: 10.1111/ele.12096
Species extinctions are biased towards higher trophic levels, and primary extinctions are often followed by unexpected secondary extinctions. Currently, predictions on the vulnerability of ecological communities to extinction cascades are based on models that focus on bottom-up effects, which cannot capture the effects of extinctions at higher trophic levels. We show, in experimental insect communities, that harvesting of single carnivorous parasitoid species led to a significant increase in extinction rate of other parasitoid species, separated by four trophic links. Harvesting resulted in the release of prey from top-down control, leading to increased interspecific competition at the herbivore trophic level. This resulted in increased extinction rates of non-harvested parasitoid species when their host had become rare relative to other herbivores. The results demonstrate a mechanism for horizontal extinction cascades, and illustrate that altering the relationship between a predator and its prey can cause wide-ranging ripple effects through ecosystems, including unexpected extinctions.

Brian W. Bowen, Luiz A. Rocha, Robert J. Toonen, Stephen A. Karl, the ToBo Laboratory, The origins of tropical marine biodiversity, Trends in Ecology & Evolution, Available online 28 February 2013, ISSN 0169-5347, 10.1016/j.tree.2013.01.018.
Recent phylogeographic studies have overturned three paradigms for the origins of marine biodiversity. (i) Physical (allopatric) isolation is not the sole avenue for marine speciation: many species diverge along ecological boundaries. (ii) Peripheral habitats such as oceanic archipelagos are not evolutionary graveyards: these regions can export biodiversity. (iii) Speciation in marine and terrestrial ecosystems follow similar processes but are not the same: opportunities for allopatric isolation are fewer in the oceans, leaving greater opportunity for speciation along ecological boundaries. Biodiversity hotspots such as the Caribbean Sea and the Indo-Pacific Coral Triangle produce and export species, but can also accumulate biodiversity produced in peripheral habitats. Both hotspots and peripheral ecosystems benefit from this exchange in a process dubbed biodiversity feedback.

Schwarz, L. K., Goebel, M. E., Costa, D. P., Kilpatrick, A. M. (2013), Top-down and bottom-up influences on demographic rates of Antarctic fur seals Arctocephalus gazella. Journal of Animal Ecology. doi: 10.1111/1365-2656.12059
1. Two major drivers in population dynamics are bottom-up processes, such as environmental factors that affect foraging success, and the top-down impacts of predation.
2. Many populations of marine mammal and seabird species appear to be declining in response to reductions in prey associated with the bottom-up effects of climate change. However, predation, which usually occurs at sea and is difficult to observe, may also play a key role.
3. We analysed drivers of population dynamics of Antarctic fur seals Arctocephalus gazella at Cape Shirreff from 1997 to 2009, including a predator that targets pre-weaned pups and bottom-up environmental effects in an ecosystem particularly sensitive to small changes in temperature.
4. We use Bayesian mark-recapture analysis to demonstrate that although large-scale environmental variability affects annual adult survival and reproduction, first year survival appears to be driving the current decline in this population (as defined by a decline in the annual number of pups born). Although the number of pups increased during the first third of the study, first year survival and recruitment of those pups in later years was very low. Such low survival may be driven by leopard seal Hydrurga leptonyx predation, particularly prior to weaning.
5. Our results suggest that without leopard seal predation, this population would most likely increase in size, despite the observed bottom-up effects of climate changes on adult vital rates. More broadly, our results show how age-targeted predation could be a major factor in population decline of K-selected colonial breeders.

Young, H., Griffin, R. H., Wood, C. L., Nunn, C. L. (2013), Does habitat disturbance increase infectious disease risk for primates?. Ecology Letters. doi: 10.1111/ele.12094
Many studies have suggested that ecosystem conservation protects human and wildlife populations against infectious disease. We tested this hypothesis using data on primates and their parasites. First, we tested for relationships between species‘ resilience to human disturbance and their parasite richness, prevalence and immune defences, but found no associations. We then conducted a meta-analysis of the effects of disturbance on parasite prevalence, which revealed no overall effect, but a positive effect for one of four types of parasites (indirectly transmitted parasites). Finally, we conducted intraspecific analyses of malaria prevalence as a function of mammalian species richness in chimpanzees and gorillas, and an interspecific analysis of geographic overlap and parasite species richness, finding that higher levels of host richness favoured greater parasite risk. These results suggest that anthropogenic effects on disease transmission are complex, and highlight the need to define the conditions under which environmental change will increase or decrease disease transmission.

Wen Wen, Xuxiong Huang, Qingkai Chen, Longfeng Feng, Likun Wei, Temperature effects on early development and biochemical dynamics of a marine fish, Inimicus japonicus, Journal of Experimental Marine Biology and Ecology, Volume 442, April 2013, Pages 22-29, ISSN 0022-0981, 10.1016/j.jembe.2013.01.025.
A study was undertaken to evaluate the development and metabolic substrates (carbohydrate, protein, lipid and fatty acids) dynamics during the embryonic and yolk-sac larval stages of the devil stinger, Inimicus japonicus, at different water temperatures (18, 21, 24, 27 and 30 °C). The hatching time was significantly shortened when the temperature increased (P < 0.05). Only 14.5% of embryos hatched at 30 °C, while the hatching rate was 92.5% at 24 °C. Larvae incubated at 21 °C displayed the greatest survival at mouth-opened larva stage (96.5%), but the rate dropped sharply when the temperature surpassed 24 °C (P < 0.05). The full length and yolk-sac volume of newly hatched larva at 18 °C and 30 °C were significantly smaller than those at 21, 24 and 27 °C. Larva at 21 °C always had the largest full length during early development. The advent of mouth-opened larvae was closely related to temperature, so were the full length and yolk volume of the mouth-opened larva. As the incubation temperature declined, the mouth-opened larva obtained longer full length and less yolk remain. Lipid was, to a large extent (47.0% of the initial amount), a fuel for development when the embryo was incubated at 18 °C. The depletion of protein in the embryo was significantly higher at 30 °C (67.6%) than that at 21 °C (31.3%). Consumption of carbohydrate was observed only in embryo at 18 °C. During the development of yolk-sac larva, a lower incubation temperature induced more protein anabolism and less lipid consumption. In I. japonicus, polar lipids (PL) constituted the principal class of lipid in eggs (74.0% of the total lipid); and it was the most consumed portion during embryogenesis in all treatments. The lipid composition in mouth-opened larva was affected by the incubation temperature. The storage triglycerides (TG) tended to comprise a higher proportion in larva incubated at 30 °C than in those at lower temperatures. The PL proportions in larva at 18 °C and 30 °C were lower than those in larvae at 21 °C, 24 °C and 27 °C. Low concentrations of polyunsaturated fatty acid (PUFA) in embryos and larvae were correlated with increased temperatures; this indicated that the rapid development at higher temperatures was at the cost of more PUFA loss. It is concluded that 21–24 °C is an appropriate range for incubation of I. japonicus eggs and larvae and that 24 °C is optimal in terms of shortening the endogenous nutritional stage and improving metabolic efficiency.

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