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The process of understanding the rapid global decline of sawfishes (Pristidae) has revealed great concern for their relatives, the wedgefishes (Rhinidae) and giant guitarfishes (Glaucostegidae), not least because all three families are targeted for their high-value and internationally-traded ‘white’ fins.The objective of this study was to assess the extinction risk of all 10 wedgefishes and 6 giant guitarfishes by applying the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, and to summarise their biogeography and habitat, life history, exploitation, use and trade, and population status.Wedgefishes and giant guitarfishes have overtaken sawfishes as the most imperilled marine fish families globally, with all but one of the 16 species facing an extremely high risk of extinction due to a combination of traits – limited biological productivity, presence in shallow waters overlapping with some of the most intense and increasing coastal fisheries in the world, and over-exploitation in target and bycatch fisheries driven by the need for animal protein and food security in coastal communities and trade in meat and high-value fins.Two species with very restricted ranges, the Clown Wedgefish (Rhynchobatus cooki) of the Indo-Malay Archipelago and the False Shark Ray (Rhynchorhina mauritaniensis) of Mauritania may be very close to extinction.Only the Eyebrow Wedgefish (Rhynchobatus palpebratus) is not assessed as Critically Endangered, due to it occurring primarily in Australia where fishing pressure is low, and some management measures are in place. Australia represents a ‘lifeboat’ for the three wedgefish and one giant guitarfish species occurring there.To conserve populations and permit recovery, a suite of measures will be required which will need to include species protection, spatial management, bycatch mitigation, and harvest and international trade management, all of which will be dependent on effective enforcement.

Aim In the marine environment, where there are few physical boundaries to gene flow, there is often nevertheless intraspecific diversity with consequences for effective conservation and management. Here, we compare two closely related dolphin species with a shared distribution in the Indian Ocean (IO) to better understand the biogeographic drivers of their population structure. Location Global oceans and seas with a focus on the Indian Ocean Taxon Tursiops sp. and Delphinus sp. Methods Bayesian, ordination, assignment, statistical and phylogenetic analyses to assess phylogeography, connectivity and population structure using microsatellite and mitochondrial DNA genetic markers. Results Both Tursiops sp. and Delphinus sp. showed population structure across the western IO and, in each case, populations in the Arabian Sea (off India, Pakistan and Oman) were most differentiated. Comparisons with other populations worldwide revealed independent lineages in this geographic region for both genera. For T. aduncus, (for which multiple sites within the IO could be compared), Bayesian modelling best supported a scenario of expansion southwards following a bottleneck event resulting in differentiation between the northern and western IO. For Delphinus, the same pattern is even more pronounced. Populations in the Arabian Sea region of the north-western IO show genetic isolation for each of the two genera, consistent with other studies of cetacean species in this region. Main conclusions We propose that changes in the intensity of the southwest monsoon during the climate cycles of the Pleistocene could have affected regional patterns of productivity and represent an important biogeographic driver promoting the observed patterns of differentiation and population dynamics seen in our focal species. Patterns of population genetic structure are consistent with phenotypic differences, suggesting an influence from distinct habitats and resources, and emphasising the need for effective conservation measures in this geographic region.

Animals and plants are metaorganisms or holobionts associated with prokaryotic and eukaryotic microbes, the diversity and community composition of which is increasingly being characterized thanks to the advent of culture-independent next-generation sequencing applications (Rohwer et al. 2002, Bang et al. 2018). In order to investigate the mechanistic underpinnings of host-microbe interactions, however, traditional culture-based approaches are critical to complement culture-independent -omics techniques. One venue for microbial cell culture-based approaches is the study of microbes associated with large aquatic vertebrates that cannot be readily studied and/or sampled under standardized and controlled conditions in the lab, such as sharks (Pogoreutz et al. 2019). The skin of sharks, rays, and skates is characterized by a mucus layer secreted by specialized secretory cells (mucous cells) in the epidermis (Meyer and Seegers 2012). Rays and skates produce sufficient amounts of epidermal mucus to be scraped off with sterile tools and collected in culture tubes, serial dilutions of which can be used for inoculation in growth media for subsequent bacterial colony picking and isolation (Tsutsui et al. 2009; Ritchie et al. 2020). Sharks however only secrete a thin and inconspicuous epidermal mucus layer in comparison (Meyer and Seegers 2012), rendering the scraping approach unfeasible. Here we detail an alternative and non-invasive protocol that allowed us to reproducibly isolate a diversity of bacteria from the skin mucus of black tip reef sharks (Carcharhinus melanopterus) using a swab sampling approach. Importantly, swabbing may help reduce sampling stress on sharks, as it does not require sharks being lifted onto a vessel. References Bang, C., Dagan, T., Deines, P., Dubilier, N., Duschl, W. J., Fraune, S., Hentschel, U., Hirt, H., Hülter, N., Lachnit, T.,Picazo, D., Pita, L., Pogoreutz, C., Rädecker, N., Saad, M.M., Schmitz, R.A., Schulenburg, H., Voolstra, C.R., Weiland-Bräuer, N., Ziegler, M., Bosch, T.C.G. (2018).Metaorganisms in extreme environments: do microbes play a role in organismal adaptation?Zoology,127, 1-19. https://doi.org/10.1016/j.zool.2018.02.004. Doane, M. P., Haggerty, J. M., Kacev, D., Papudeshi, B., & Dinsdale, E. A. (2017). The skin microbiome of the common thresher shark (Alopias vulpinus) has low taxonomic and gene functionβ‐diversity.Environmental Microbiology Reports,9, 357-373. https://doi.org/10.1111/1758-2229.12537. Meyer, W., and Seegers, U. (2012) Basics of skin structure and function in elasmobranchs: a review. J Fish Biol 80:1940–1967. https://doi.org/10.1111/j.1095-8649.2011.03207.x Lane, D. J. (1991). 16S/23S rRNA sequencing. In: Nucleic acid techniques in bacterial systematics. Stackebrandt, E., Goodfellow, M., eds. John Wiley and Sons, New York, NY, pp. 115-175. Pogoreutz, C., and C.R. Voolstra. 2018. Isolation, culturing, and cryopreservation ofEndozoicomonas (Gammaproteobacteria: Oceanospirillales: Endozoicomonadaceae) from reef-building corals. Protocols.iohttps://doi.org/10.17504/protocols.io.t2aeqae Pogoreutz, C., Gore, M. A., Perna, G., Millar, C., Nestler, R., Ormond, R. F., Clarke, C.R. & Voolstra, C.R. (2019). Similar bacterial communities on healthy and injured skin of black tip reef sharks.BMC Animal Microbiome,1, 9. https://doi.org/10.1186/s42523-019-0011-5. Ritchie, K. B., Schwarz, M., Mueller, J., Lapacek, V. A., Merselis, D., Walsh, C. J., & Luer, C. A. (2017). Survey of antibiotic-producing bacteria associated with the epidermal mucus layers of rays and skates.Frontiers in Microbiology,8, 1050. https://doi.org/10.3389/fmicb.2017.01050. Rohwer, F., Seguritan, V., Azam, F., & Knowlton, N. (2002). Diversity and distribution of coral-associated bacteria.Marine Ecology Progress Series,243, 1-10. doi:10.3354/meps243001. Sanders, E. R. (2012). Aseptic laboratory techniques: plating methods.Journal of Visualized Experiments,63, e3064. Tsutsui, S., Yamaguchi, M., Hirasawa, A., Nakamura, O., & Watanabe, T. (2009). Common skate (Raja kenojei) secretes pentraxin into the cutaneous secretion: the first skin mucus lectin in cartilaginous fish.Journal of Biochemistry, 146, 295-306.https://doi.org/10.1093/jb/mvp069.

Aim The Caribbean reef shark (Carcharhinus perezi) is one of few extant reef sharks inhabiting the Atlantic Ocean. Its variability in movements across habitat types suggests the possibility of a complex genetic population structure. Here, we use mitochondrial and nuclear DNA to investigate the genetic connectivity of the Caribbean reef shark across contemporary and evolutionary time-scales and relate our findings to the ecology of this understudied species. Location Tropical western Atlantic and Caribbean. Methods Samples were obtained from 216 individuals from six western Atlantic and Caribbean locations. Individuals were genotyped at seven nuclear microsatellite DNA loci and sequenced at two mitochondrial (control region [CR]; NADH dehydrogenase subunit 4 [ND4]) and one nuclear locus (lactate dehydrogenase [LDH]). Analyses to resolve the population genetic structure and evolutionary history of this species were adopted. Results Sequencing of the CR (1,068 bp, n = 216), ND4 (741 bp, n = 213) and LDH (258 bp, n = 165) loci, resolved 11, 8 and 13 unique haplotypes (or alleles), respectively. Overall, Caribbean reef sharks showed low levels of genetic diversity and most marker sets identified strong genetic differences (FST and ΦST) between sharks sampled in Brazil versus all other locations (msat FST > 0.017; CR-ND4 ΦST > 0.013). Mitochondrial DNA showed evidence of increased genetic partitioning among western North Atlantic sampling sites, although widespread haplotype sharing (~85%–92%) and a shallow population history were found. Main Conclusions Findings of genetic differentiation are concordant with previous movement studies showing residency and/or site-fidelity to specific locations by individuals. However, similar to other reef shark studies, we found that the level of genetic connectivity among populations was context dependent—i.e., sharks occupying isolated habitats showed greater genetic differentiation compared with those sharks occupying semi-isolated or continuous reef habitats. Furthermore, low genetic diversity and a shallow mitochondrial population history were found, suggesting historical demographic fluctuations, including population collapse and more recent expansions.

Phylogeographic inference has provided extensive insight into the relative roles of geographical isolation and ecological processes during evolutionary radiations. However, the importance of cross-lineage admixture in facilitating adaptive radiations is increasingly being recognised, and suggested as a main cause of phylogenetic uncertainty. In this study, we used a double digest RADseq protocol to provide a high resolution (~4 Million bp) nuclear phylogeny of the Delphininae. Phylogenetic resolution of this group has been especially intractable, likely because it has experienced a recent species radiation. We carried out cross-lineage reticulation analyses, and tested for several sources of potential bias in determining phylogenies from genome sampling data. We assessed the divergence time and historical demography of T. truncatus and T. aduncus by sequencing the T. aduncus genome and comparing it with the T. truncatus reference genome. Our results suggest monophyly for the genus Tursiops, with the recently proposed T. australis species falling within the T. aduncus lineage. We also show the presence of extensive cross-lineage gene flow between pelagic and European coastal ecotypes of T. truncatus, as well as in the early stages of diversification between spotted (Stenella frontalis; Stenella attenuata), spinner (Stenella longirostris), striped (Stenella coeruleoalba), common (Delphinus delphis), and Fraser’s (Lagenodelphis hosei) dolphins. Our study suggests that cross-lineage gene flow in this group has been more extensive and complex than previously thought. In the context of biogeography and local habitat dependence, these results improve our understanding of the evolutionary processes determining the history of this lineage.

© 2017 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/, Phylogeography can provide insight into the potential for speciation and identify geographic regions and evolutionary processes associated with species richness and evolutionary endemism. In the marine environment, highly mobile species sometimes show structured patterns of diversity, but the processes isolating populations and promoting differentiation are often unclear. The Delphinidae (oceanic dolphins) are a striking case in point and, in particular, bottlenose dolphins (Tursiops spp.). Understanding the radiation of species in this genus is likely to provide broader inference about the processes that determine patterns of biogeography and speciation, because both fine-scale structure over a range of kilometers and relative panmixia over an oceanic range are known for Tursiops populations. In our study, novel Tursiops spp. sequences from the northwest Indian Ocean (including mitogenomes and two nuDNA loci) are included in a worldwide Tursiops spp. phylogeographic analysis. We discover a new ‘aduncus’ type lineage in the Arabian Sea (off India, Pakistan and Oman) that diverged from the Australasian lineage ∼261 Ka. Effective management of coastal dolphins in the region will need to consider this new lineage as an evolutionarily significant unit. We propose that the establishment of this lineage could have been in response to climate change during the Pleistocene and show data supporting hypotheses for multiple divergence events, including vicariance across the Indo-Pacific barrier and in the northwest Indian Ocean. These data provide valuable transferable inference on the potential mechanisms for population and species differentiation across this geographic range.

Shark tourism is a popular but controversial activity. We obtained insights into this industry via a global e-mailed questionnaire completed by 45 diving/snorkelling operators who advertised shark experiences (shark operators) and 49 who did not (non-shark operators). 42% of shark operators used an attractant to lure sharks and 93% stated they had a formal code of conduct which 86% enforced "very strictly". While sharks were reported to normally ignore people, 9 operators had experienced troublesome behaviour from them. Whilst our research corroborates previous studies indicating minimal risk to humans from most shark encounters, a precautionary approach to provisioning is required to avoid potential ecological and societal effects of shark tourism. Codes of conduct should always stipulate acceptable diver behaviour and appropriate diver numbers and shark operators should have a moral responsibility to educate their customers about the need for shark conservation.

Following centuries of exploitation, basking sharks (Cetorhinus maximus) are considered by IUCN as Endangered in the Northeast Atlantic, where they have now been substantially protected for over two decades. However, the present size of this population remains unknown. We investigated the use of photo-identification of individuals’ dorsal fins, combined with mark-recapture methodology, to investigate the size of populations of basking shark within the west coast of Scotland. From a total of 921 encounters photographed between 2004 and 2011, 710 sharks were found to be individually identifiable based on dorsal fin damage and natural features. Of these, only 41 individuals were re-sighted, most commonly both within days of, and close to the site of, the initial encounter. A smaller number were re-sighted after longer periods of up to two years. A comparison of the distinguishing features of individuals on first recording and subsequent re-sighting showed that in almost all cases these features remained little changed, suggesting the low re-sighting rate was not due to a loss of distinguishing features. Because of the low number of re-sighting we were not able to produce reliable estimates for the long-term regional population. However, for one 50 km diameter study area between the islands of Mull, Coll and Tiree, we were able to generate closed-population estimates for 6–9 day periods in 2010 of 985 (95% CI = 494–1683), and in 2011 of 201 (95% CI = 143–340). For the same 2011 period an open-population model generated a similar estimate of 213 (95% CI = 111–317). Otherwise the low rate and temporal patterning of re-sightings support the view that such local basking shark populations are temporary, dynamic groupings of individuals drawn from a much larger regional population than previously supposed. The study demonstrated the feasibility and limitations of photo-identification as a non-invasive technique for identifying individual basking sharks.

Abstract. Aggressive interactions were observed in two primate species: rhesus monkeys, which have a female-bonded social system, and hamadryas baboons, which have a non-female-bonded social system. Dyadic and triadic aggression and assertiveness were examined under controlled ecological conditions and demographic structure, focusing on interactions initiated by adult females between and within two groups of each species. The literature suggests that rhesus monkeys interact with a broad class of partners while hamadryas baboons have limited social interactions. Primates have flexible social systems, however, and differences are probably not due to species specificity. Rhesus females used dyadic interactions more frequently in conflict situations while hamadryas females often involved a third individual. Aggression was directed within more than between groups in both species; hamadryas females sometimes targeted females in other groups, however. The results suggest that interactions initiated by hamadryas females may be overlooked as they use more subtle and complex behaviour than do rhesus females. This difference is discussed in relation to the social system.

Abstract. Models of the ecology of primate groups have predicted that foraging competition among adult females in female-bonded species should occur in rich, clumped food conditions, rather than in meagre dispersed conditions. Competition should occur within groups rather than between groups and non-female-bonded species are not expected to compete. In female-bonded species, females remain in their natal group and develop strong affiliative bonds among female members. In non-female-bonded species, females neither remain in their natal group nor develop affiliative bonds with other female members. While it is not feasible to test the evolution of primate groups, the immediate situation is of interest and can be investigated. The present study tested the predictions of the models in two socially housed primate species, rhesus monkeys and hamadryas baboons, representing a female-bonded and a non-female-bonded species, respectively. Food distribution was manipulated to produce appropriate conditions, and comparisons were made within and between groups as well as between the two species. Neither species conformed completely to the models, although the hamadryas baboons did in most respects. Between-group competition proved to be important with dominance a deciding factor. Spatial and temporal conditions affected competition in rhesus monkeys and temporal conditions in hamadryas baboons. Within-group competition occurred largely in dispersed meagre conditions with food equally available in time. The two species used different strategies to the same end; the hamadryas baboons were more efficient at obtaining food while the rhesus monkeys had a more flexible foraging strategy. Food storage was used by both species as a strategy in foraging competition.

Identifying individuals through time can provide information on population size, composition, survival and growth rates. Identification using photographs of distinctive physical characteristics has been used in many species to replace conventional marker tagging. We evaluated photographic records over 7 years of Vulnerable whale sharks Rhincodon typus, at an aggregation in the Seychelles, for estimation of population size and structure. We collected 11,681 photographs of which only 1,149 were suitable for comparison using semi-automated matching software (I3S) of individual spot patterns behind the gills. Photo-identification showed that there was considerable loss of marker tags and enabled an estimation of the rate of tag loss. The combination of photo-identification with marker tagging identified a total of 512 individual sharks over 2001–2007. Of these, there were 115 resightings in subsequent years with two sharks identified in 2001 resighted 5 years later in 2006 and another shark sighted in 2001 resighted in 2007. Estimates of abundance using conventional open mark–recapture models for 2004–2007 were 348–488 sharks (95% confidence interval), with a high level of entry into the population by itinerants. Annual apparent survival probability was 0.343–0.781 over 2004–2007, with an average annual recapture probability of 0.201. These results are the first to suggest a highly transient population of whale sharks around the Seychelles, indicating that international or at least regional-scale conservation approaches are required.

Feeding in the marine cladoceran, Penilia avirostris Dana, was investigated using plastic micronic beads as a controlled particle source. The range of bead size ingested by P. avirostris was largely limited to diameters of 20 μm and below, perhaps a competitive advantage in nature, was found that: (1) as the concentration of beads increased, the number of beads ingested increased: (2) as the number of P. avirostris increased, the number of beads ingested increased: and (3) the number of beads ingested also increased with body size. The size of P. avirostris , however, did not appear to limit the size of bead ingested, while larger sized animals may be better competitors for particles.

Male satin bowerbirds use feathers to decorate their bowers and often steal feathers and other decorations from the bowers of other males. Decorations are a key element in sexual display and tracking their movement between bowers provides the first detailed information about this unique pattern of sexual competition. For two field seasons the movement of marked feathers was followed. Males varied greatly in stealing activity. The most active feather thieves were often from areas where bowers were close together and they were involved in reciprocal stealing with males at adjacent bowers. The rate of stealing by males was significantly correlated with the number of feathers on their bowers. This suggests that stealing is important in determining the level of bower decoration and mating success. Patterns of stealing behaviour support models of sexual selection which suggest that male interactions are important in influencing female choice through their effect on the quality of male display.

1. The influence of spacing systems upon fitness was investigated by measuring parameters assumed to affect fitness directly. These included reproduction, shelter and food. 2. Three classes of C. capistratus were found, based upon their motional behaviour. These were Residents, Randoms and Transients. 3. Residents remained in and reused particular areas repeatedly. Transients used separate areas and were not usually observed in any particular area. Randoms behaved in a random fashion relative to the other two classes described. Further differences between the three classes were as follows. 4. C. capistratus have been observed in pairs, but pairs were of short duration and partners were frequently of the same as well as of the opposite sex. There is no offspring care system. 5. Predation on C. capistratus is very low. It was found that Residents were more harassed by neighbouring Eupomacentrids than Randoms or Transients were. Thus it did not appear to be an advantage to Residents to have a shelter from harassment and predation or for reproduction. 6. Residents gained more nips on preferred species and size of food. Aggression was significantly related to food in Residents, while non-food related activities were significantly related to aggression in Randoms and Transients. 7. The spacing system and its effect on the social organization of C. capistratus described occurs diurnally, when the fish feed. It is a flexible system as the fish may change classes, and perhaps it is only 'economical' to spend the time and energy for the defense of a site as a Resident for food and only when necessary.

PrefaceWhenever animals are used in research, minimizing pain and distress and promoting good welfare should be as important an objective as achieving the experimental results. This is important for humanitarian reasons, for good science, for economic reasons and in order to satisfy the broad legal principles in international legislation. It is possible to refine both husbandry and procedures to minimize suffering and improve welfare in a number of ways, and this can be greatly facilitated by ensuring that up-to-date information is readily available. The need to provide such information led the British Veterinary Association Animal Welfare Foundation (BVAAWF), the Fund for the Replacement of Animals in Medical Experiments (FRAME), the Royal Society for the Prevention of Cruelty to Animals (RSPCA) and the Universities Federation for Animal Welfare (UFAW) to establish a Joint Working Group on Refinement (JWGR) in the UK. The chair is Professor David Morton and the secretariat is provided by the RSPCA. This report is the ninth in the JWGR series. The RSPCA is opposed to the use of animals in experiments that cause pain, suffering, distress or lasting harm and together with FRAME has particular concerns about the continued use of non-human primates. The replacement of primate experiments is a primary goal for the RSPCA and FRAME. However, both organizations share with others in the Working Group, the common aim of replacing primate experiments wherever possible, reducing suffering and improving welfare while primate use continues. The reports of the refinement workshops are intended to help achieve these aims. This report produced by the British Veterinary Association Animal Welfare Foundation (BVAAWF)/Fund for the Replacement of Animals in Medical Experiments (FRAME)/Royal Society for the Prevention of Cruelty to Animals (RSPCA)/Universities Federation for Animal Welfare (UFAW) Joint Working Group on Refinement (JWGR) sets out practical guidance on refining the husbandry and care of non-human primates (hereinafter primates) and on minimizing the adverse effects of some common procedures. It provides a valuable resource to help understand the physical, social and behavioural characteristics and needs of individual primates, and is intended to develop and complement the existing literature and legislative guidelines. Topics covered include refinements in housing, husbandry and common procedures such as restraint, identification and sampling, with comprehensive advice on issues such as primate communication, assessing and facilitating primate wellbeing, establishing and maintaining social groups, environmental and nutritional enrichment and animal passports. The most commonly used species are the key focus of this resource, but its information and recommendations are generally applicable to other species, provided that relevant individual species characteristics are taken into account.