Browsing by Author "Chapple, Taylor K."

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    Analysing detection gaps in acoustic telemetry data to infer differential movement patterns in fish
    Williamson, Michael J.; Tebbs, Emma J.; Dawson, Terence P.; Curnick, David J.; Ferretti, Francesco; Carlisle, Aaron B.; Chapple, Taylor K.; Schallert, Robert J.; Tickler, David M.; Harrison, Xavier A.; Block, Barbara A.; Jacoby, David M. P. (2021-03)
    A wide array of technologies are available for gaining insight into the movement of wild aquatic animals. Although acoustic telemetry can lack the fine-scale spatial resolution of some satellite tracking technologies, the substantially longer battery life can yield important long-term data on individual behavior and movement for low per-unit cost. Typically, however, receiver arrays are designed to maximize spatial coverage at the cost of positional accuracy leading to potentially longer detection gaps as individuals move out of range between monitored locations. This is particularly true when these technologies are deployed to monitor species in hard-to-access locations. Here, we develop a novel approach to analyzing acoustic telemetry data, using the timing and duration of gaps between animal detections to infer different behaviors. Using the durations between detections at the same and different receiver locations (i.e., detection gaps), we classify behaviors into "restricted" or potential wider "out-of-range" movements synonymous with longer distance dispersal. We apply this method to investigate spatial and temporal segregation of inferred movement patterns in two sympatric species of reef shark within a large, remote, marine protected area (MPA). Response variables were generated using network analysis, and drivers of these movements were identified using generalized linear mixed models and multimodel inference. Species, diel period, and season were significant predictors of "out-of-range" movements. Silvertip sharks were overall more likely to undertake "out-of-range" movements, compared with gray reef sharks, indicating spatial segregation, and corroborating previous stable isotope work between these two species. High individual variability in "out-of-range" movements in both species was also identified. We present a novel gap analysis of telemetry data to help infer differential movement and space use patterns where acoustic coverage is imperfect and other tracking methods are impractical at scale. In remote locations, inference may be the best available tool and this approach shows that acoustic telemetry gap analysis can be used for comparative studies in fish ecology, or combined with other research techniques to better understand functional mechanisms driving behavior.
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    Biological Earth observation with animal sensors
    Jetz, Walter; Tertitski, Grigori; Kays, Roland; Mueller, Uschi; Wikelski, Martin; Akesson, Susanne; Anisimov, Yury; Antonov, Aleksey; Arnold, Walter; Bairlein, Franz; Balta, Oriol; Baum, Diane; Beck, Mario; Belonovich, Olga; Belyaev, Mikhail; Berger, Matthias; Berthold, Peter; Bittner, Steffen; Blake, Stephen; Block, Barbara; Bloche, Daniel; Boehning-Gaese, Katrin; Bohrer, Gil; Bojarinova, Julia; Bommas, Gerhard; Bourski, Oleg; Bragin, Albert; Bragin, Alexandr; Bristol, Rachel; Brlik, Vojtech; Bulyuk, Victor; Cagnacci, Francesca; Carlson, Ben; Chapple, Taylor K.; Chefira, Kalkidan F.; Cheng, Yachang; Chernetsov, Nikita; Cierlik, Grzegorz; Christiansen, Simon S.; Clarabuch, Oriol; Cochran, William; Cornelius, Jamie Margaret; Couzin, Iain; Crofoot, Margret C.; Cruz, Sebastian; Davydov, Alexander; Davidson, Sarah; Dech, Stefan; Dechmann, Dina; Demidova, Ekaterina; Dettmann, Jan; Dittmar, Sven; Dorofeev, Dmitry; Drenckhahn, Detlev; Dubyanskiy, Vladimir; Egorov, Nikolay; Ehnbom, Sophie; Ellis-Soto, Diego; Ewald, Ralf; Feare, Chris; Fefelov, Igor; Fehervari, Peter; Fiedler, Wolfgang; Flack, Andrea; Froboese, Magnus; Fufachev, Ivan; Futoran, Pavel; Gabyshev, Vyachaslav; Gagliardo, Anna; Garthe, Stefan; Gashkov, Sergey; Gibson, Luke; Goymann, Wolfgang; Gruppe, Gerd; Guglielmo, Chris; Hartl, Phil; Hedenstrom, Anders; Hegemann, Arne; Heine, Georg; Ruiz, Maggi Hieber; Hofer, Heribert; Huber, Felix; Hurme, Edward; Iannarilli, Fabiola; Illa, Marc; Isaev, Arkadiy; Jakobsen, Bent; Jenni, Lukas; Jenni-Eiermann, Susi; Jesmer, Brett R.; Jiguet, Frederic; Karimova, Tatiana; Kasdin, N. Jeremy; Kazansky, Fedor; Kirillin, Ruslan; Klinner, Thomas; Knopp, Andreas; Koelzsch, Andrea; Kondratyev, Alexander; Krondorf, Marco; Ktitorov, Pavel; Kulikova, Olga; Kumar, R. Suresh; Kuenzer, Claudia; Larionov, Anatoliy; Larose, Christine; Liechti, Felix; Linek, Nils; Lohr, Ashley; Lushchekina, Anna; Mansfield, Kate; Matantseva, Maria; Markovets, Mikhail; Marra, Peter; Masello, Juan F.; Melzheimer, Joerg; Menz, Myles HM M.; Menzie, Stephen; Meshcheryagina, Swetlana; Miquelle, Dale; Morozov, Vladimir; Mukhin, Andrey; Mueller, Inge; Mueller, Thomas; Navedo, Juan G.; Nathan, Ran; Nelson, Luke; Nemeth, Zoltan; Newman, Scott; Norris, Ryan; Nsengimana, Olivier; Okhlopkov, Innokentiy; Oles, Wioleta; Oliver, Ruth; O'Mara, Teague; Palatitz, Peter; Partecke, Jesko; Pavlick, Ryan; Pedenko, Anastasia; Perry, Alys; Pham, Julie; Piechowski, Daniel; Pierce, Allison; Piersma, Theunis; Pitz, Wolfgang; Plettemeier, Dirk; Pokrovskaya, Irina; Pokrovskaya, Liya; Pokrovsky, Ivan; Pot, Morrison; Prochazka, Petr; Quillfeldt, Petra; Rakhimberdiev, Eldar; Ramenofsky, Marilyn; Ranipeta, Ajay; Rapczynski, Jan; Remisiewicz, Magdalena; Rozhnov, Viatcheslav; Rienks, Froukje; Rozhnov, Vyacheslav; Rutz, Christian; Sakhvon, Vital; Sapir, Nir; Safi, Kamran; Schaeuffelhut, Friedrich; Schimel, David; Schmidt, Andreas; Shamoun-Baranes, Judy; Sharikov, Alexander; Shearer, Laura; Shemyakin, Evgeny; Sherub, Sherub; Shipley, Ryan; Sica, Yanina; Smith, Thomas B.; Simonov, Sergey; Snell, Katherine; Sokolov, Aleksandr; Sokolov, Vasiliy; Solomina, Olga; Spina, Fernando; Spoelstra, Kamiel; Storhas, Martin; Sviridova, Tatiana; Swenson, George; Taylor, Phil; Thorup, Kasper; Tsvey, Arseny; Tucker, Marlee; Tuppen, Sophie; Turner, Woody; Twizeyimana, Innocent; van der Jeugd, Henk; van Schalkwyk, Louis; van Toor, Marielle; Viljoen, Pauli; Visser, Marcel E.; Volkmer, Tamara; Volkov, Andrey; Volkov, Sergey; Volkov, Oleg; von Ronn, Jan AC C.; Vorneweg, Bernd; Wachter, Bettina; Waldenstrom, Jonas; Weber, Natalie; Wegmann, Martin; Wehr, Aloysius; Weinzierl, Rolf; Weppler, Johannes; Wilcove, David; Wild, Timm; Williams, Hannah J.; Wilshire, John H.; Wingfield, John; Wunder, Michael; Yachmennikova, Anna; Yanco, Scott; Yohannes, Elisabeth; Zeller, Amelie; Ziegler, Christian; Ziecik, Anna; Zook, Cheryl (Cell Press, 2022-05-22)
    Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmental change.
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    Detecting Mediterranean White Sharks with Environmental DNA
    Jenrette, Jeremy F.; Jenrette, Jennifer L.; Truelove, N. Kobun; Moro, Stefano; Dunn, Nick I.; Chapple, Taylor K.; Gallagher, Austin J.; Gambardella, Chiara; Schallert, Robert; Shea, Brendan D.; Curnick, David J.; Block, Barbara A.; Ferretti, Francesco (The Oceanography Society, 2023-01)
    The white shark (Carcharodon carcharias) is a globally distributed, ecologically important top predator whose biology and population dynamics are challenging to study. Basic biological parameters remain virtually unknown in the Mediterranean Sea due to its historically low population density, dwindling population size, and lack of substantial sightings. White sharks are considered Critically Endangered in the Mediterranean Sea, and recent analyses suggest that the population has declined by 52% to 96% from historical levels in different Mediterranean sectors (Moro et al., 2020). Thus, white shark sightings dating back to 1860 are being used to estimate population trajectories throughout the entire region. Though the population size is unknown, remaining individuals are thought to be primarily restricted to a handful of hotspots deemed important for their reproduction and foraging. One of these hypothesized hotspots is the Sicilian Channel, which accounts for 19% of total historical sightings.
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    Emergent research and priorities for shark and ray conservation
    Jorgensen, Salvador J.; Micheli, Fiorenza; White, Timothy D.; Van Houtan, Kyle S.; Alfaro-Shigueto, Joanna; Andrzejaczek, Samantha; Arnoldi, Natalie S.; Baum, Julia K.; Block, Barbara; Britten, Gregory L.; Butner, Cheryl; Caballero, Susana; Cardeñosa, Diego; Chapple, Taylor K.; Clarke, Shelley; Cortés, Enric; Dulvy, Nicholas K.; Fowler, Sarah; Gallagher, Austin J.; Gilman, Eric; Godley, Brendan J.; Graham, Rachel T.; Hammerschlag, Neil; Harry, Alastair V.; Heithaus, Michael R.; Hutchinson, Melanie; Huveneers, Charlie; Lowe, Chris G.; Lucifora, Luis O.; MacKeracher, Tracy; Mangel, Jeffrey C.; Barbosa Martins, Ana Paula; McCauley, Douglas J.; McClenachan, Loren; Mull, Christopher; Natanson, Lisa J.; Pauly, Daniel; Pazmiño, Diana A.; Pistevos, Jennifer C.A.; Queiroz, Nuno; Roff, George; Shea, Brendan D.; Simpfendorfer, Colin A.; Sims, David W.; Ward-Paige, Christine; Worm, Boris; Ferretti, Francesco (Inter-Research, 2022-02-28)
    Over the past 4 decades there has been a growing concern for the conservation status of elasmobranchs (sharks and rays). In 2002, the first elasmobranch species were added to Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Less than 20 yr later, there were 39 species on Appendix II and 5 on Appendix I. Despite growing concern, effective conservation and management remain challenged by a lack of data on population status for many species, human−wildlife interactions, threats to population viability, and the efficacy of conservation approaches. We surveyed 100 of the most frequently published and cited experts on elasmobranchs and, based on ranked responses, prioritized 20 research questions on elasmobranch conservation. To address these questions, we then convened a group of 47 experts from 35 institutions and 12 countries. The 20 questions were organized into the following broad categories: (1) status and threats, (2) population and ecology, and (3) conservation and management. For each section, we sought to synthesize existing knowledge, describe consensus or diverging views, identify gaps, and suggest promising future directions and research priorities. The resulting synthesis aggregates an array of perspectives on emergent research and priority directions for elasmobranch conservation.
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    Shark movement strategies influence poaching risk and can guide enforcement decisions in a large, remote marine protected area
    Jacoby, David M. P.; Ferretti, Francesco; Freeman, Robin; Carlisle, Aaron B.; Chapple, Taylor K.; Curnick, David J.; Dale, Jonathan J.; Schallert, Robert J.; Tickler, David; Block, Barbara A. (British Ecological Society, 2020-05-12)
    Large, remote marine protected areas (MPAs) containing both reef and pelagic habitats, have been shown to offer considerable refuge to populations of reef‐associated sharks. Many large MPAs are, however, impacted by illegal fishing activity conducted by unlicensed vessels. While enforcement of these reserves is often expensive, it would likely benefit from the integration of ecological data on the mobile animals they are designed to protect. Consequently, shark populations in some protected areas continue to decline, as they remain a prime target for illegal fishers. To understand shark movements and their vulnerability to illegal fishing, 3 years of acoustic tracking data, from 101 reef‐associated sharks, were analysed as movement networks to explore the predictability of movement patterns and identify key movement corridors within the British Indian Ocean Territory (BIOT) MPA. We examined how space use and connectivity overlap with spatially explicit risk of illegal fishing, through data obtained from the management consultancy enforcing the MPA. Using individual‐based models, the movement networks of two sympatric shark species were efficiently predicted with distance‐decay functions (>95% movements accurately predicted). Model outliers were used to highlight the locations with unexpectedly high movement rates where MPA enforcement patrols might most efficiently mitigate predator removal. Activity space estimates and network metrics illustrate that silvertip sharks were more dynamic, less resident and link larger components of the MPA than grey reef sharks. However, we show that this behaviour potentially enhances their exposure to illegal fishing activity. Synthesis and applications. Marine protected area (MPA) enforcement strategies are often limited by resources. The British Indian Ocean Territory MPA, one of the world's largest ‘no take’ MPAs, has a single patrol vessel to enforce 640,000 km2 of open ocean, atoll and reef ecosystems. We argue that to optimize the patrol vessel search strategy and thus enhance their protective capacity, ecological data on the space use and movements of desirable species, such as large‐bodied reef predators, must be incorporated into management plans. Here, we use electronic tracking data to evaluate how shark movement dynamics influence species mortality trajectories in exploited reef ecosystems. In doing so we discuss how network analyses of such data might be applied for protected area enforcement.