Abstract View

Sarah Benhaiem, Heribert Hofer, Martin Dehnhard, Janine Helms, and Marion L.
East Sibling competition and hunger increase allostatic load in spotted hyaenas
Biol. Lett. June 23, 2013 9 3 20130040; doi:10.1098/rsbl.2013.0040 1744-957X

Allostatis is the process of maintaining homeostatis through behavioural or physiological responses to challenges, and its cumulative energetic cost is termed allostatic load. The allostatic load hypothesis predicts that hunger and the mechanisms that establish and maintain social dominance should have a strong impact on allostatic load. In spotted hyaenas, dominance between twin siblings emerges during intense early competition for maternal milk and involves trained winner/loser effects. Conflict over access to teats declines with age as behavioural dominance conventions are established. In young litters, the allostatic load of subordinates measured in terms of faecal glucocorticoid metabolite concentrations (fGMCs) should be higher than that of dominants. When low milk provisioning threatens survival, hungry subordinates are more assertive, particularly when competing against a dominant sister. Dominants challenged by assertive subordinates should have allostatic loads and fGMCs above those of dominants with subordinates that adhere to dominance conventions. We show that in young litters, subordinates had significantly higher fGMCs than dominants, and dominant sisters had significantly higher fGMCs than dominant brothers. When hungry, both dominants and subordinates had significantly higher fGMCs than when fed. Our results provide evidence that hunger and sibling competition affect allostatic load in spotted hyaenas.

Zootaxa 3646 (3): 251–264 (03 May 2013)
The identity of Rana margaritifera Laurenti, 1768 (Anura, Bufonidae)

Rana margaritifera was described by Laurenti in 1768 and currently is associated to the genus Rhinella, under the combination Rhinella margaritifera. Currently, the R. margaritifera species group consists of 16 recognized species. Furthermore, many additional species have been suggested to exist in this group which highlights the ambiguity surrounding the identity of Rhinella margaritifera and impend further description of the species in this group. After an exhaustive bibliographic review, we concluded that the recent designation of a lectotype for R. margaritifera is invalid according with Art.73, ICZN, 1999. Herein, we designate and provide the description of a neotype for Rana margaritifera Laurenti, 1768.

Zootaxa 3646 (3): 265–276 (03 May 2013)
Monophyly of the Agoniatinae (Characiformes: Characidae)

The Characidae is the most diverse family of Neotropical fishes, currently encompassing more than one thousand valid species. Some subgroups within this family still lack phylogenetic definitions, being diagnosed on the basis of combination of characters, a common procedure in pre-cladistic studies. Agoniatinae, currently composed by two valid species, Agoniates anchovia and A. halecinus, is one of them. In the present study the Agoniatinae is redefined using a phylogenetically oriented comparative survey that included the two Agoniates species plus 114 species representing all the major clades of the Characidae and their closest relatives. Six derived morphological characters are identified as synapomorphies for the Agoniatinae: deep notch on the posterior region of the maxilla joining the ventral margin of the infraorbital 2; dentigerous portion of premaxilla shorter than the ascending process of this bone; dentary canine preceded by tricuspid teeth; ventral margin of the urohyal markedly convex; base of the uppermost ray of the ventral lobe of the caudal fin much expanded, being as deep as the distal margin of hypural 2; and levator arcus palatini muscle with a posterodorsal bundle of fibers attaching to the dorsal face of the sphenotic spine.

Zootaxa 3646 (3): 289–296 (03 May 2013)
A new species of the genus Opisthotropis Günther, 1872 (Squamata: Colubridae: Natricinae) from Guangdong Province, China

A new natricid snake of the genus Opisthotropis Günther, 1872, Opisthotropis laui sp. nov., is described from Mt. Gudou, Jiangmen City, Guangdong Province, China. The new species can be distinguished from other congeners by the combination of the following characters: dorsal scales weakly keeled throughout, in 25:23:23 rows; 10 supralabials; 11 infralabials; two internasals, longer than wide, not touching the loreal; one loreal, not touching the eye; one preocular; two postoculars; one anterior temporal scale; 152 ventrals; 53 subcaudals; body and tail dark olive above, with light yellow crossbars.

Mitchell L. Scott, Martin J. Whiting, Jonathan K. Webb, Richard Shine, Chemosensory discrimination of social cues mediates space use in snakes, Cryptophis nigrescens (Elapidae), Animal Behaviour, Available online 2 May 2013, ISSN 0003-3472, 10.1016/j.anbehav.2013.04.003.
Snakes have traditionally been viewed as solitary, asocial animals whose habitat use is driven by temperature, prey and predators. However, recent studies suggest that snake spatial ecology may also be socially mediated. We examined the influence of conspecific chemical cues on refuge selection in a small nocturnal snake (the small-eyed snake) that engages in male contest competition. Females preferred refuges containing scent cues from conspecifics (of either sex) rather than scentless refuges. Males preferred female-scented rather than male-scented refuges, and preferred the scent of larger (and hence, more fecund) females than smaller females. Males spent more time in refuges containing the scent of smaller rather than larger males, but males that lost a contest did not avoid the refuge scented by the winner and therefore did not show evidence of the winner–loser effect. Females preferred refuges scented by larger males. Small-eyed snakes can distinguish conspecific sex and body size using chemical cues, and they use these cues to select alternative refuge sites. We suggest that social factors play a significant role in driving snake spatial distribution patterns in the wild and that snakes may exhibit more complex social systems than has generally been believed.

Inga Geipel, Elisabeth K.V. Kalko, Katja Wallmeyer, Mirjam Knörnschild, Postweaning maternal food provisioning in a bat with a complex hunting strategy, Animal Behaviour, Available online 2 May 2013, ISSN 0003-3472, 10.1016/j.anbehav.2013.03.040.
Adult animals of many taxa exhibit extended parental care by transferring food to inexperienced offspring, thus allocating nutritional and sometimes even informational benefits such as the acquisition of adult dietary preferences and foraging skills. In bats, postweaning food provisioning is severely understudied, despite the taxon’s diverse and complex foraging strategies. The Neotropical common big-eared bat, Micronycteris microtis, preys on relatively large insects gleaned from vegetation, finding its silent and motionless prey by echolocation. The demands of this cognitively challenging hunting strategy make M. microtis a likely candidate for maternal postweaning food provisioning. We studied five free-living mother–pup pairs in their night roost using infrared video recordings. Each mother exclusively fed her own pup and mother–pup recognition was mutual. Provisioned pups were volant and had started their own hunting attempts. Weaned pups were provisioned for 5 subsequent months with a variety of insects, reflecting the adult diet. Mothers transferred over 50% of their prey to pups. Maternal prey transfers declined as pups matured, whereas the pups‘ own prey captures increased. During prey transfers, aggressive behaviour between mothers and pups was rare. We argue that postweaning maternal food provisioning might yield two informational benefits for M. microtis pups. First, learning how to handle large and well-defended prey is mandatory for inexperienced pups and could be practised with prey items provided by their mothers. Second, acoustically characteristic echo images of prey items could be gained during mother–pup prey transfers, probably facilitating the successful acquisition of M. microtis’s complex hunting strategy.

Newsome, Thomas M., Stephens, Danielle, Ballard, Guy-Anthony, Dickman, Christopher R., and Fleming, Peter J. S. (2013) Genetic profile of dingoes (Canis lupus dingo) and free-roaming domestic dogs (C. l. familiaris) in the Tanami Desert, Australia. Wildlife Research , http://dx.doi.org/10.1071/WR12128
The dingo is currently at risk of extinction, with hybridisation with domestic dogs seen as a key threat. Here, we determine if human-provided resources facilitate hybridisation in the Tanami Desert of central Australia. Our results demonstrate that dingo sociality and pack structures can be altered where human-provided food and water are constantly available and suggest that this could accelerate rates of hybridisation. The development of appropriate domestic-waste management strategies to reduce opportunities for genetic mixing should therefore be a high priority in remote Australian communities. Photograph by Newmont.

Guo Song-Lin, Wang Yu, Feng Jian-Jun, Yang Qiu-Hua, Lu Pan-Pan, Hu Linlin, Zhao JingPin, Immune effects of a bivalent expressed outer membrane protein to American eels (Anguilla rostrota), Fish & Shellfish Immunology, Available online 2 May 2013, ISSN 1050-4648, 10.1016/j.fsi.2013.04.027.
The specific and non-specific immune parameters and protection of American eels (Anguilla rostrata) were evaluated after immunized eels with a bivalent expressed out membrane protein (OMP) of porinⅡ of Aeromonas hydrophila and ompS2 of Edwardsiella tarda. One hundred eighty eels were distributed into 3 equal groups and intraperitoneal (i.p) injection with phosphate-buffered saline (PBS group), formalin-killed-whole-cell (FKC) of A. hydrophila and E. tarda (FKC group) or the bivalent OMP (OMP group). The lymphocytes and red blood cells collected on 14, 21 and 42 days post-vaccination were used to evaluate the stimulation index (SI) and the sera collected on 14, 21, 28 and 42 days were used to assize the titers of specific antibody as well as lysozyme activity. Lysozyme activities in skin mucus, suspension of liver and kidney were also recorded on 14, 21 and 28 days. On 28 d post-vaccination, eels from all three groups were challenged by i.p injection of live A. hydrophila or E. tarda. The results show that, compared with the PBS group, proliferation of lymphocytes in OMP group was significantly (P < 0.05) enhanced on 21 days, and the serum titers of anti-A. hydrophila and anti- E. tarda antibody in eels of FKC and OMP group were significant increased (P < 0.05 or P < 0.01) on 14, 21 and 28 days. Activity of the lysozyme in serum, skin mucus, liver and kidney were significant changed (P <0.05 or P <0.01) between the three groups. Relative Percent Survival (RPS) after challenged with A. hydrophila on 28 days post immunization in two vaccinated groups vs. PBS group were 50%, and the RPS challenge E. tarda in FKC and OMP vs. PBS group were 50% and 37.5% respectively. These results suggest that American eels immunized with the bivalent OMP would positively affect specific as well as non-specific immune parameters and protect against infection by the two pathogens in freshwater farming.

Mercedes López, Pilar Foronda, Carlos Feliu, Mariano Hernández
Genetic characterization of black rat (Rattus rattus) of the Canary Islands: origin and colonization
Biological Invasions, May 2013

In the Canary Islands two invasive rat species, Rattus rattus and Rattus norvegicus are present, but little is known about the origin and colonization. To this end, a molecular study was performed on R. rattus from the Archipelago and from the nearest continents. Partial cytochrome b gene sequencing offered very low levels of haplotype and nucleotide diversities, with only seven haplotypes identified. All of them belong to the European Lineage I, specifically to the “ship rat” cluster. The haplotype network showed a star-like topology. Haplotype distribution showed a genetic subdivision between eastern and central/western islands, suggesting a double colonization event. This hypothesis is congruent with historical human colonization and it is similar to that proposed for the rodent parasite Hymenolepis diminuta. In addition, a possible role of the Canary Islands as a faunal link with the European and American continents is discussed.

José Martín, Pilar López, Mario Garrido, Ana Pérez-Cembranos, Valentín Pérez-Mellado, Inter-island variation in femoral secretions of the Balearic lizard, Podarcis lilfordi (Lacertidae), Biochemical Systematics and Ecology, Volume 50, October 2013, Pages 121-128, ISSN 0305-1978, 10.1016/j.bse.2013.03.044.
Many lizards use femoral gland secretions in intraspecific communication. Although there is a consistent interspecific variation in chemical composition of secretions, considerable variation is also often found between populations, which may affect conspecifc recognition and lead to speciation processes. Balearic lizards (Podarcis lilfordi) are currently distributed only in several isolated islets offshore of the main islands with different environmental conditions (vegetation, diet, density of population, etc). Also, there is a high genetic variability between populations. We examined whether there was a similar variation in the composition of the femoral secretions of male lizards, and which could be the causes of such variation. By using GC–MS analyses, we found 75 lipophilic compounds in femoral gland secretions of male P. lilfordi from three representative island populations. Main compounds were steroids (94.4%), mainly cholesterol, but we also found alkanes, ketones, waxy esters, squalene, carboxylic acids and their ethyl esters, alcohols and other minor compounds. However, there were clear differences between populations with respect to the number and relative proportions of compounds. Using the patterns of presence and abundance of compounds in secretions it is possible to predict the population of origin of a lizard. We discuss how these differences could be explained considering genetic and environmental differences between populations.

Mariana M. Vidal, Mathias M. Pires, Paulo R. Guimarães Jr., Large vertebrates as the missing components of seed-dispersal networks, Biological Conservation, Available online 2 May 2013, ISSN 0006-3207, 10.1016/j.biocon.2013.03.025.
Large-bodied frugivores may play a key role in the networks of plants and their seed dispersers. These species, however, are often threatened by human impacts that lead to defaunation. In this paper, we discuss the potential implications of the loss of large frugivores for seed-dispersal networks. First, we review the role of large vertebrates as seed dispersers in different tropical ecosystems to show that these species are likely to be important components of seed-dispersal networks. Second, we showed that, despite their importance, large vertebrates are absent from most of the seed-dispersal networks described in the available literature. We identified three main reasons for this absence: (1) large vertebrates have already died out in the studied areas; (2) studies focus on particular taxonomic groups that consist mostly of small birds; and (3) it is inherently difficult to describe the interactions of naturally rare and secretive species such as large vertebrates. We argue that a proper evaluation of the importance of large frugivores within seed-dispersal networks would benefit from considering aspects other than the frequency of interactions. We suggest weighting pairwise interactions by their ecological consequences to quantify the contribution of large frugivores to outcomes of seed dispersal, such as landscape connectivity.

Natalie S. Haussmann, Elizabeth M. Rudolph, Jesse M. Kalwij, Trevor McIntyre, Fur seal populations facilitate establishment of exotic vascular plants, Biological Conservation, Volume 162, June 2013, Pages 33-40, ISSN 0006-3207, 10.1016/j.biocon.2013.03.024.
The cessation of seal harvesting has prompted a recovery of previously decimated fur seal (Arctocephalus gazella and Arctocephalus tropicalis) populations across the Southern Ocean region. Although the associated increase in seal-related soil disturbance is known to impact indigenous vegetation, the effect of increasing fur seal numbers on exotic plant species is not yet clear. Here, we compare plant species composition and cover between 26 sites with high fur seal impact paired with nearby control sites on sub-Antarctic Marion Island. Seal-affected sites had a significantly higher number and cover of exotic plants, specifically of the widespread sub-Antarctic invaders, Poa annua and Sagina procumbens, than control sites. Furthermore, some of the native species, most notably the disturbance-sensitive species, Blechnum penna-marina, were significantly less abundant in seal-affected sites compared to controls. We propose that this is a result of both physical trampling, which opens up niches for exotics by damaging natives, and nutrient enrichment of the soils, giving exotic species a competitive advantage over natives. While other studies have noticed associations between exotic plant species and indigenous animal disturbance, this is, to the best of our knowledge, the first study to empirically show that the successful recovery of fur seal populations can have undesirable side-effects such as the enhanced persistence of exotic plant species. We recommend that alien plant management plans specifically include areas of increased animal disturbance into their programmes.

B.T. Hirsch, R. Kays, P.A. Jansen, Evidence for cache surveillance by a scatter-hoarding rodent
Animal Behaviour, Available online 3 May 2013, ISSN 0003-3472, 10.1016/j.anbehav.2013.04.005.

The mechanisms by which food-hoarding animals are capable of remembering the locations of numerous cached food items over long time spans has been the focus of intensive research. The ‘memory enhancement hypothesis’ states that hoarders reinforce spatial memory of their caches by repeatedly revisiting cache sites, yet no study has documented this behaviour in wild animals. We investigated whether scatter-hoarding Central American agoutis, Dasyprocta punctata, actively survey their seed caches. We placed remote cameras at sites where seeds were buried by known individuals and at nearby random locations to compare the behaviour and visiting rates between owners and naïve individuals. We found that cache owners were almost four times more likely to walk near their cache than to walk past random locations. Moreover, cache owners that passed in front of a cache camera were more than twice as likely to approach their caches than were naïve individuals but half as likely to excavate the seed when interacting with the cache. We conclude that agoutis remember the location of cached seeds, are aware of their ownership and actively survey their caches. Surveillance could serve to monitor cache theft and food quality as well as enhance spatial memory of cache locations; thus, this behaviour could have important fitness benefits and may be exhibited by other scatter-hoarding animals.

Spatiotemporal variations in resources affect activity and movement patterns of white-tailed deer (Odocoileus virginianus) at high density
Ariane Massé, Steeve D. Côté
Canadian Journal of Zoology, 2013, 91:252-263, 10.1139/cjz-2012-0297

Although activity budget, movements, and habitat use of herbivores have been extensively studied, few studies have simultaneously examined these behaviors at several temporal scales. We investigated the influence of spatiotemporal variations in forage and climate on the activity and movement patterns of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) at high density, in a predator-free ecosystem impacted by long-term browsing. We used GPS telemetry and activity sensors to monitor seasonal activity budgets, movements, and patterns of habitat use within the home ranges of 24 female deer at three temporal scales: (1) season, (2) within season, and (3) daily. At large temporal scale, deer were less active and moved less during winter than during summer. Within each season, deer reduced their activity and movements in areas where forage resources were abundant and when climatic conditions were more difficult. On a daily scale, summer and winter movements peaked at dusk, but habitat selection neither changed with period of the day nor activity (foraging vs. resting). These results provide empirical evidence on how environmental constraints can modulate the trade-offs between forage acquisition and exposure to limiting factors.

Hannah M. Buchanan-Smith, Joana Griciute, Sophia Daoudi, Rebecca Leonardi, Andrew Whiten, Interspecific interactions and welfare implications in mixed species communities of capuchin (Sapajus apella) and squirrel monkeys (Saimiri sciureus) over 3 years, Applied Animal Behaviour Science, Available online 3 May 2013, ISSN 0168-1591, 10.1016/j.applanim.2013.04.004.
Species have complex relationships with others in the wild, and some such as capuchin (Sapajus apella) and squirrel monkeys (Saimiri sciureus) naturally choose to associate with each other. There are a number of benefits of exhibiting such species in correspondingly mixed communities in captivity to enhance welfare through increased social complexity, which is potentially environmentally enriching in restricted captive enclosures. Monitoring the interactions between species is critical, however, particularly when members of one species are considerably larger and potentially more aggressive than the other. We report on the frequency and nature of interspecific interactions between S. apella and S. sciureus during four time periods over 3 years (2008–2010) following the formation of two mixed species groups at the ‘Living Links to Human Evolution’ Research Centre in Edinburgh Zoo, Scotland. Both the rate and the distribution of interspecific interactions among aggressive, affiliative and neutral categories of behaviour varied over time (P < 0.05). We predicted that S. apella would engage in more interspecific, particularly aggressive, interactions than S. sciureus than vice versa, as they are the larger, more social species and have a more pugnacious temperament. This was the case overall (P < 0.05), and particularly in 2009 and 2010. We predicted that affiliative interactions would increase over time as the number of youngsters increased and as the youngsters grew up together, establishing equable relationships and “territorial” boundaries. The data did not support this prediction. Both the most affiliative and least aggressive interspecific interactions were observed following internal enclosure refurbishment in 2008 and hence we argue that good enclosure design and husbandry is the most important factor in promoting positive interactions between individuals in mixed species groups. We conclude that long-term monitoring is important, and when combined with appropriate husbandry and enclosure upkeep, the welfare of individuals is enhanced in mixed species groups by the presence of other species.

Catarina Campos, M. Filipa Castanheira, Sofia Engrola, Luísa M. P. Valente, Jorge M. O. Fernandes, Luís E. C. Conceição
Fish Physiology and Biochemistry, May 2013
Rearing temperature affects Senegalese sole (Solea senegalensis) larvae protein metabolic capacity

The present work examined the short- and long-term effects of three rearing temperatures on protein metabolism and growth trajectories of Senegalese sole larvae using 14C-labelled Artemia protein as feed. A first feeding trial was performed on larvae reared at 15, 18 and 21 °C (at 26, 17 and 14 days post-hatching (dph), respectively) and a second trial conducted on post-larvae after transfer to the same rearing temperature (~20 °C) (49, 35 and 27 dph, in larvae initially reared at 15, 18 and 21 °C, respectively). Temperature greatly influenced larvae relative growth rate (RGR) and survival, since growth at 15 °C was severely depressed. Protein digestibility and retention was highest at 18 °C during the first trial (85.35 ± 1.16 and 86.34 ± 2.33 %, respectively). However, during the second trial, post-larvae from 15 °C had the highest feed intake and protein digestibility (3.58 ± 1.54 and 75.50 ± 1.35 %, respectively), although retention was similar between treatments. Furthermore, after transfer to 20 °C larvae from 15 °C experienced compensatory growth, which was observed until 121 dph, and confirmed by RGR values, which were significantly higher at 15 ºC than at 21 ºC or 18 ºC. from the present study show that Solea senegalensis larval development, survival and protein digestion and retention are highly affected by thermal history.

Terry J. Ord, Judy A. Stamps, Jonathan B. Losos, Convergent evolution in the territorial communication of a classic adaptive radiation: Caribbean Anolis lizards, Animal Behaviour, Available online 3 May 2013, ISSN 0003-3472, 10.1016/j.anbehav.2013.03.037.
To demonstrate adaptive convergent evolution, it must be shown that shared phenotypes have evolved independently in different lineages and that a credible selection pressure underlies adaptive evolution. There are a number of robust examples of adaptive convergence in morphology for which both these criteria have been met, but examples from animal behaviour have rarely been tested as rigorously. Adaptive convergence should be common in behaviour, especially behaviour used for communication, because the environment often shapes the evolution of signal design. In this study we report on the origins of a shared design of a territorial display among Anolis species of lizards from two island radiations in the Caribbean. These lizards perform an elaborate display that consists of a complex series of headbobs and dewlap extensions. The way in which these movements are incorporated into displays is generally species specific, but species on the islands of Jamaica and Puerto Rico also share fundamental aspects in display design, resulting in two general display types. We confirm these display types are convergent (the consequence of independent evolution on each island) and provide evidence that the convergence was driven by selection for enhanced signal efficiency. Our study shows how adaptation to common environmental variables can drive the evolution of adaptive, convergent signals in distantly related species.

MASSEN, J. J.M., ANTONIDES, A., ARNOLD, A.-M. K., BIONDA, T. and KOSKI, S. E. (2013), A Behavioral View on Chimpanzee Personality: Exploration Tendency, Persistence, Boldness, and Tool-Orientation Measured With Group Experiments. Am. J. Primatol.. doi: 10.1002/ajp.22159
Human and nonhuman animals show personality: temporal and contextual consistency in behavior patterns that vary among individuals. In contrast to most other species, personality of chimpanzees, Pan troglodytes, has mainly been studied with non-behavioral methods. We examined boldness, exploration tendency, persistence and tool-orientation in 29 captive chimpanzees using repeated experiments conducted in an ecologically valid social setting. High temporal repeatability and contextual consistency in all these traits indicated they reflected personality. In addition, Principal Component Analysis revealed two independent syndromes, labeled exploration-persistence and boldness. We found no sex or rank differences in the trait scores, but the scores declined with age. Nonetheless, there was considerable inter-individual variation within age-classes, suggesting that behavior was not merely determined by age but also by dispositional effects. In conclusion, our study complements earlier rating studies and adds new traits to the chimpanzee personality, thereby supporting the existence of multiple personality traits among chimpanzees. We stress the importance of ecologically valid behavioral research to assess multiple personality traits and their association, as it allows inclusion of ape studies in the comparison of personality structures across species studied behaviorally, and furthers our attempts to unravel the causes and consequences of animal personality.

Stephen K. Pikesley, Pierre Didier Agamboue, Eric Augowet Bonguno, François Boussamba, Floriane Cardiec, J. Michael Fay, Angela Formia, Brendan J. Godley, William F. Laurance, Brice Didier Koumba Mabert, Cheryl Mills, Gil Avery Mounguengui Mounguengui, Carine Moussounda, Solange Ngouessono, Richard J. Parnell, Guy-Philippe Sounguet, Bas Verhage, Lee White, Matthew J. Witt, Here today, here tomorrow: Beached timber in Gabon, a persistent threat to nesting sea turtles, Biological Conservation, Available online 3 May 2013, ISSN 0006-3207, 10.1016/j.biocon.2012.11.002.
The African country of Gabon has seen decadal increases in commercial logging. An unforeseen consequence of this has been that many coastal areas, including several National Parks and Reserves, have suffered severe pollution from beached timber. This has the potential to adversely affect nesting sea turtles, particularly the leatherback turtle (Dermochelys coriacea) for which Gabon constitutes the world’s largest rookery. In this study, we analyse aerial survey data (2003, 2007 and 2011) to determine the temporal persistence and spatial extent of beached timber, and by integrating spatial data on nesting, ascertain regions where beached timber poses the greatest threat to nesting leatherback turtles. There was no marked difference in the number of beached logs recorded across the study area during the period, with 15,160, 13,528 and 17,262 logs recorded in the three years, respectively. There was, however, a significant difference in abundance of beached logs among geographical areas. Analysis highlighted two coastal areas where nesting leatherback turtles were likely to be at greatest risk from beached timber. At one such site, Kingere, within Pongara National Park, where both logs and turtle densities are high, monitoring in 2006/2007 and 2007/2008 suggested that between 1.6% and 4.4% of leatherback turtles could be entrapped at this site. Given the dynamic nature of Gabon’s coastal environment, and the potential limitations of aerial surveys, densities of beached timber could be greater than this analysis reveals. We also propose, that despite recent export restrictions of whole logs, their environmental persistence potentially represents a long-term problem.

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