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2. Continent-wide declines in shallow reef life over a decade of ocean warming

Author

Edgar, Graham J., Stuart-Smith, Rick D., Heather, Freddie J., Barrett, Neville S., Turak, Emre, Sweatman, Hugh, Emslie, Michael J., Brock, Danny J., Hicks, Jamie, French, Ben, Baker, Susan C., Howe, Steffan A., Jordan, Alan, Knott, Nathan A., Mooney, Peter, Cooper, Antonia T., Oh, Elizabeth S., Soler, German A., Mellin, Camille, Ling, Scott D., Dunic, Jillian C., Turnbull, John W., Day, Paul B., Larkin, Meryl F., Seroussi, Yanir, Stuart-Smith, Jemina, Clausius, Ella, Davis, Tom R., Shields, Joe, Shields, Derek, Johnson, Olivia J., Fuchs, Yann Herrera, Denis-Roy, Lara, Jones, Tyson, and Bates, Amanda E.

Published
2023
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5. Assessing lobster and co-predator feeding rates on barrens-forming sea urchins in South East Australia.

Author

Day, Jeremy K., Knott, Nathan A., Swadling, Daniel S., Huggett, Megan J., and Gaston, Troy F.

Subjects
SPINY lobsters, LOBSTERS, ECHINODERMATA, PREDATORY animals, PREDATION, SEA urchins
Abstract

Globally, key predators such as lobsters are thought to control urchins. In southeastern Australia, the role of Sagmariasus verreauxi (eastern rock lobster) as a key predator of the native urchin Centrostephanus rodgersii (long-spined urchin) has been questioned while the sympatric Heliocidaris erythrogramma (short-spined urchin) may be eaten more frequently. To test this, we tethered and filmed 100 urchins (50 C. rodgersii and 50 H. erythrogramma) outside of a lobster den over 25 nights to identify predators and quantify predation rates, time to feeding onset and handling time. Sagmariasus verreauxi exhibited very low predation rates (4%), despite being filmed walking past urchins repeatedly whereas Heterodontus galeatus (crested horn shark) was the main predator (45%). Predation rates by all predators (lobsters and sharks) were influenced primarily by tethering night but not urchin size or species. Predation increased throughout the study and while H. erythrogramma and C. rodgersii were eaten at similar rates, there was a trend for lobsters to eat H. erythrogramma and sharks to eat C. rodgersii. Feeding onset had no significant predictors though large C. rodgersii took longer to handle during feeding for both predators. Importantly, sharks readily consumed 25 C. rodgersii up to 121 mm Test Diameter (TD) while lobsters only ate one C. rodgersii (58 mm TD). These findings, although from only one test location, provide important insights into the species eating urchins and highlight the potential significance of overlooked predators such as H. galeatus. [ABSTRACT FROM AUTHOR]

Published
2024
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7. Globally coordinated acoustic aquatic animal tracking reveals unexpected, ecologically important movements across oceans, lakes and rivers

Author

Lennox, Robert J., Whoriskey, Frederick G., Verhelst, Pieterjan, Vandergoot, Christopher S., Soria, Marc, Reubens, Jan, Rechisky, Erin L., Power, Michael, Murray, Taryn, Mulder, Ingeborg, Markham, James L., Lowerre‐barbieri, Susan K., Lindley, Steven T., Knott, Nathan A., Kessel, Steven T., Iverson, Sara, Huveneers, Charlie, Heidemeyer, Maike, Harcourt, Robert, Griffin, Lucas P., Friess, Claudia, Filous, Alexander, Fetterplace, Lachlan C., Danylchuk, Andy J., Daly, Ryan, Cowley, Paul, Cooke, Steven J., Chávez, Elpis J., Blaison, Antonin, Whoriskey, Kim, Lennox, Robert J., Whoriskey, Frederick G., Verhelst, Pieterjan, Vandergoot, Christopher S., Soria, Marc, Reubens, Jan, Rechisky, Erin L., Power, Michael, Murray, Taryn, Mulder, Ingeborg, Markham, James L., Lowerre‐barbieri, Susan K., Lindley, Steven T., Knott, Nathan A., Kessel, Steven T., Iverson, Sara, Huveneers, Charlie, Heidemeyer, Maike, Harcourt, Robert, Griffin, Lucas P., Friess, Claudia, Filous, Alexander, Fetterplace, Lachlan C., Danylchuk, Andy J., Daly, Ryan, Cowley, Paul, Cooke, Steven J., Chávez, Elpis J., Blaison, Antonin, and Whoriskey, Kim

Abstract

Acoustic telemetry is a popular approach used to track many different aquatic animal taxa in marine and freshwater systems. However, information derived from focal studies is typically resource‐ and geography‐limited by the extent and placement of acoustic receivers. Even so, animals tagged and tracked in one region or study may be detected unexpectedly at distant locations by other researchers using compatible equipment, who ideally share that information. Synergies through national and global acoustic tracking networks are facilitating significant discoveries and unexpected observations that yield novel insight into the movement ecology and habitat use of wild animals. Here, we present a selection of case studies that highlight unexpected tracking observations or absence of observations where we expected to find animals in aquatic systems around the globe. These examples span freshwater and marine systems across spatiotemporal scales ranging from adjacent watersheds to distant ocean regions. These unexpected movements showcase the power of collaborative telemetry networks and serendipitous observations. Unique and unexpected observations such as those presented here can capture the imagination of both researchers and members of the public, and improve understanding of movement and connectivity within aquatic ecosystems.

Published
2024
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8. Spiny lobster predation of barrens‐forming sea urchins is not limited by body size, but may be overstated.

Author

Day, Jeremy K., Knott, Nathan A., Swadling, Daniel S., Ayre, David, Huggett, Megan J., and Gaston, Troy F.

Subjects
SPINY lobsters, REEF ecology, PREDATORY aquatic animals, MARINE ecology, LOBSTERS, SEA urchins, PREDATION
Abstract

Worldwide, lobsters are considered key predators that control urchin populations. It has been widely reported that lobster size plays a significant role in the size of urchins they feed on, as does the size of the urchin. Generally, it is thought that small palinurid "spiny" lobsters measuring less than 120 mm carapace length (CL) are morphologically incapable of eating urchins, while large lobsters are voracious predators. Urchin size is expected to affect predation with larger urchins of greater than 90 mm test diameter (TD) presenting the most difficult prey. These generalities, however, have not been quantitatively tested for the eastern spiny lobster Sagmariasus verreauxi and recently the accepted size paradigm for lobsters eating urchins has come into question. The aim of this study was to assess whether lobster predation on urchins would differ with urchin size or species, or the size of lobster. Our results indicate that S. verreauxi does not fit the common lobster patterns regarding urchin predation. There were generally low rates of predation and a significant negative relationship between feeding and both lobster size and urchin size. We found that small lobsters were capable urchin predators with a higher likelihood of eating urchins than larger lobsters, which were more reluctant predators. While we did find the expected effect of smaller urchins being significantly more vulnerable prey, there was none of the expected size limitations for small lobsters eating large urchins and predation did not differ between urchin species, indicating that this was a general pattern. Overall, we observed low rates of predation, suggesting that either S. verreauxi may not be a key urchin predator like other lobster species elsewhere, or that small lobsters are underestimated as urchin predators in temperate marine ecosystems. [ABSTRACT FROM AUTHOR]

Published
2024
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11. Globally coordinated acoustic aquatic animal tracking reveals unexpected, ecologically important movements across oceans, lakes and rivers

Author

Lennox, Robert J., primary, Whoriskey, Frederick G., additional, Verhelst, Pieterjan, additional, Vandergoot, Christopher S., additional, Soria, Marc, additional, Reubens, Jan, additional, Rechisky, Erin L., additional, Power, Michael, additional, Murray, Taryn, additional, Mulder, Ingeborg, additional, Markham, James L., additional, Lowerre‐Barbieri, Susan K., additional, Lindley, Steven T., additional, Knott, Nathan A., additional, Kessel, Steven T., additional, Iverson, Sara, additional, Huveneers, Charlie, additional, Heidemeyer, Maike, additional, Harcourt, Robert, additional, Griffin, Lucas P., additional, Friess, Claudia, additional, Filous, Alexander, additional, Fetterplace, Lachlan C., additional, Danylchuk, Andy J., additional, Daly, Ryan, additional, Cowley, Paul, additional, Cooke, Steven J., additional, Chávez, Elpis J., additional, Blaison, Antonin, additional, and Whoriskey, Kim, additional

Published
2023
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14. Corrigendum : Assessing National Biodiversity Trends for Rocky and Coral Reefs through the Integration of Citizen Science and Scientific Monitoring Programs

Author

STUART-SMITH, RICK D., EDGAR, GRAHAM J., BARRETT, NEVILLE S., BATES, AMANDA E., BAKER, SUSAN C., BAX, NICHOLAS J., BECERRO, MIKEL A., BERKHOUT, JUST, BLANCHARD, JULIA L., BROCK, DANIEL J., CLARK, GRAEME F., COOPER, ANTONIA T., DAVIS, TOM R., DAY, PAUL B., DUFFY, J. EMMETT, HOLMES, THOMAS H., HOWE, STEFFAN A., JORDAN, ALAN, KININMONTH, STUART, KNOTT, NATHAN A., LEFCHECK, JONATHAN S., LING, SCOTT D., PARR, AMANDA, STRAIN, ELISABETH, SWEATMAN, HUGH, and THOMSON, RUSSELL

Published
2017

15. Assessing National Biodiversity Trends for Rocky and Coral Reefs through the Integration of Citizen Science and Scientific Monitoring Programs

Author

STUART-SMITH, RICK D., EDGAR, GRAHAM J., BARRETT, NEVILLE S., BATES, AMANDA E., BAKER, SUSAN C., BAX, NICHOLAS J., BECERRO, MIKEL A., BERKHOUT, JUST, BLANCHARD, JULIA L., BROCK, DANIEL J., CLARK, GRAEME F., COOPER, ANTONIA T., DAVIS, TOM R., DAY, PAUL B., DUFFY, J. EMMETT, HOLMES, THOMAS H., HOWE, STEFFAN A., JORDAN, ALAN, KININMONTH, STUART, KNOTT, NATHAN A., LEFCHECK, JONATHAN S., LING, SCOTT D., PARR, AMANDA, STRAIN, ELISABETH, SWEATMAN, HUGH, and THOMSON, RUSSELL

Published
2017

18. Scaling of Activity Space in Marine Organisms across Latitudinal Gradients

Author

Udyawer, Vinay, primary, Huveneers, Charlie, additional, Jaine, Fabrice, additional, Babcock, Russell C., additional, Brodie, Stephanie, additional, Buscot, Marie-Jeanne, additional, Campbell, Hamish A., additional, Harcourt, Robert G., additional, Hoenner, Xavier, additional, Lédée, Elodie J. I., additional, Simpfendorfer, Colin A., additional, Taylor, Matthew D., additional, Armstrong, Asia, additional, Barnett, Adam, additional, Brown, Culum, additional, Bruce, Barry, additional, Butcher, Paul A., additional, Cadiou, Gwenael, additional, Couturier, Lydie I. E., additional, Currey-Randall, Leanne, additional, Drew, Michael, additional, Dudgeon, Christine L., additional, Dwyer, Ross G., additional, Espinoza, Mario, additional, Ferreira, Luciana C., additional, Fowler, Anthony, additional, Harasti, David, additional, Harborne, Alastair R., additional, Knott, Nathan A., additional, Lee, Kate, additional, Lloyd, Matt, additional, Lowry, Michael, additional, Marzullo, Teagan, additional, Matley, Jordan, additional, McAllister, Jaime D., additional, McAuley, Rory, additional, McGregor, Frazer, additional, Meekan, Mark, additional, Mills, Kade, additional, Norman, Bradley M., additional, Oh, Beverly, additional, Payne, Nicholas L., additional, Peddemors, Vic, additional, Piddocke, Toby, additional, Pillans, Richard D., additional, Reina, Richard D., additional, Rogers, Paul, additional, Semmens, Jayson M., additional, Smoothey, Amy, additional, Speed, Conrad W., additional, van der Meulen, Dylan, additional, and Heupel, Michelle R., additional

Published
2023
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21. Scaling of Activity Space in Marine Organisms across Latitudinal Gradients

Author

Udyawer, Vinay, Huveneers, Charlie, Jaine, Fabrice, Babcock, Russell C., Brodie, Stephanie, Buscot, Marie-jeanne, Campbell, Hamish A., Harcourt, Robert G., Hoenner, Xavier, Lédée, Elodie J. I., Simpfendorfer, Colin A., Taylor, Matthew D., Armstrong, Asia, Barnett, Adam, Brown, Culum, Bruce, Barry, Butcher, Paul A., Cadiou, Gwenael, Couturier, Lydie I. E., Currey-randall, Leanne, Drew, Michael, Dudgeon, Christine L., Dwyer, Ross G., Espinoza, Mario, Ferreira, Luciana C., Fowler, Anthony, Harasti, David, Harborne, Alastair R., Knott, Nathan A., Lee, Kate, Lloyd, Matt, Lowry, Michael, Marzullo, Teagan, Matley, Jordan, Mcallister, Jaime D., Mcauley, Rory, Mcgregor, Frazer, Meekan, Mark, Mills, Kade, Norman, Bradley M., Oh, Beverly, Payne, Nicholas L., Peddemors, Vic, Piddocke, Toby, Pillans, Richard D., Reina, Richard D., Rogers, Paul, Semmens, Jayson M., Smoothey, Amy, Speed, Conrad W., Van Der Meulen, Dylan, Heupel, Michelle R., Udyawer, Vinay, Huveneers, Charlie, Jaine, Fabrice, Babcock, Russell C., Brodie, Stephanie, Buscot, Marie-jeanne, Campbell, Hamish A., Harcourt, Robert G., Hoenner, Xavier, Lédée, Elodie J. I., Simpfendorfer, Colin A., Taylor, Matthew D., Armstrong, Asia, Barnett, Adam, Brown, Culum, Bruce, Barry, Butcher, Paul A., Cadiou, Gwenael, Couturier, Lydie I. E., Currey-randall, Leanne, Drew, Michael, Dudgeon, Christine L., Dwyer, Ross G., Espinoza, Mario, Ferreira, Luciana C., Fowler, Anthony, Harasti, David, Harborne, Alastair R., Knott, Nathan A., Lee, Kate, Lloyd, Matt, Lowry, Michael, Marzullo, Teagan, Matley, Jordan, Mcallister, Jaime D., Mcauley, Rory, Mcgregor, Frazer, Meekan, Mark, Mills, Kade, Norman, Bradley M., Oh, Beverly, Payne, Nicholas L., Peddemors, Vic, Piddocke, Toby, Pillans, Richard D., Reina, Richard D., Rogers, Paul, Semmens, Jayson M., Smoothey, Amy, Speed, Conrad W., Van Der Meulen, Dylan, and Heupel, Michelle R.

Abstract

Unifying models have shown that the amount of space used by animals (e.g., activity space, home range) scales allometrically with body mass for terrestrial taxa; however, such relationships are far less clear for marine species. We compiled movement data from 1,596 individuals across 79 taxa collected using a continental passive acoustic telemetry network of acoustic receivers to assess allometric scaling of activity space. We found that ectothermic marine taxa do exhibit allometric scaling for activity space, with an overall scaling exponent of 0.64. However, body mass alone explained only 35% of the variation, with the remaining variation best explained by trophic position for teleosts and latitude for sharks, rays, and marine reptiles. Taxon-specific allometric relationships highlighted weaker scaling exponents among teleost fish species (0.07) than sharks (0.96), rays (0.55), and marine reptiles (0.57). The allometric scaling relationship and scaling exponents for the marine taxonomic groups examined were lower than those reported from studies that had collated both marine and terrestrial species data derived using various tracking methods. We propose that these disparities arise because previous work integrated summarized data across many studies that used differing methods for collecting and quantifying activity space, introducing considerable uncertainty into slope estimates. Our findings highlight the benefit of using large-scale, coordinated animal biotelemetry networks to address cross-taxa evolutionary and ecological questions.

Published
2023
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24. Tracking widespread climate-driven change on temperate and tropical reefs

Author

Stuart-Smith, Rick D., primary, Edgar, Graham J., additional, Clausius, Ella, additional, Oh, Elizabeth S., additional, Barrett, Neville S., additional, Emslie, Michael J., additional, Bates, Amanda E., additional, Bax, Nic, additional, Brock, Daniel, additional, Cooper, Antonia, additional, Davis, Tom R., additional, Day, Paul B., additional, Dunic, Jillian C., additional, Green, Andrew, additional, Hasweera, Norfaizny, additional, Hicks, Jamie, additional, Holmes, Thomas H., additional, Jones, Ben, additional, Jordan, Alan, additional, Knott, Nathan, additional, Larkin, Meryl F., additional, Ling, Scott D., additional, Mooney, Peter, additional, Pocklington, Jacqueline B., additional, Seroussi, Yanir, additional, Shaw, Ian, additional, Shields, Derek, additional, Smith, Margo, additional, Soler, German A., additional, Stuart-Smith, Jemina, additional, Turak, Emre, additional, Turnbull, John W., additional, and Mellin, Camille, additional

Published
2022
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32. Diel and tidal cycles regulate larval dynamics in salt marshes and mangrove forests

Author

Ricardo, Gerard F., Davis, Andrew R., Knott, Nathan A., and Minchinton, Todd E.

Subjects
Larvae -- Distribution, Mangrove swamps -- Research, Hydrologic cycle -- Research, Tidal marshes -- Research, Company distribution practices, Biological sciences
Abstract

Variation in the release and recruitment of larvae of estuarine invertebrates affects the distribution and abundance of adults, as well as trophic interactions in both the plankton and the benthos. Larval release and supply are often timed to environmental cycles such as the diel and tidal cycles. Here, we determined using plankton tows whether the abundance of larvae spanning salt marsh and mangrove habitats across the intertidal landscape varied with diel and tidal cycles. Using three different sampling designs across two sites and within each of two estuaries over a 12-month period, we covered a range of spatial and temporal scales. This allowed us to test the general prediction that densities of meroplankton in the water column would be greater during nocturnal ebb tides than during other phases of the diel or tidal cycle. As predicted, nocturnal ebb tides yielded the highest densities of meroplanktonic larvae and were dominated by first-stage crab zoeae and this finding was most pronounced in the salt marsh. Throughout the course of the year, greater numbers of meroplankters consistently occurred during the ebb tide compared with the flood tide. The densities of other taxa (e.g. gastropods and polychaetes) showed no clear trends with diel or tidal cycles. This study highlights the effects of these pervasive physical cycles on the timing of larval release and supply in the salt marsh-mangrove complex, and emphasises their contribution to the trophic interactions and the dynamics of benthic populations within estuaries., Introduction Larval release and supply (the availability of larvae to settle) are important processes for the future structuring of adult populations of marine invertebrates (Underwood and Fair-weather 1989; Minchinton and [...]

Published
2014
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33. Non‐lethal sampling does not misrepresent trophic level or dietary sources for Sagmariasus verreauxi (eastern rock lobster).

Author

Day, Jeremy Karl, Knott, Nathan Aaron, Swadling, Daniel, Ayre, David, Huggett, Megan, and Gaston, Troy

Subjects
*SPINY lobsters, *CRAYFISH, *MARINE parks & reserves, *NITROGEN isotopes, *CARBON isotopes, *STABLE isotopes
Abstract

Rationale: Isotope analysis can be used to investigate the diets of predators based on assimilation of nitrogen and carbon isotopes from prey. Recent work has shown that tissues taken from legs, antennae or abdomen of lobsters can give different indications of diet, but this has never been evaluated for Sagmariasus verreauxi (eastern rock lobster). Work is now needed to prevent erroneous conclusions being drawn about lobster food webs, and undertaking this work could lead to developing non‐lethal sampling methodologies. Non‐lethal sampling for lobsters is valuable both ethically and for areas of conservation significance such as marine reserves. Method: We evaluated this by dissecting 76 lobsters and comparing δ13C and δ15N isotope values in antennae, leg and abdomen tissue from the same individuals ranging from 104 to 137 mm carapace length. Stable isotope values were determined using a Europa EA GSL elemental analyser coupled with Hydra 20–20 Isoprime IRMS. Results: We found the abdomen δ13C values to be lower than other tissues by 0.3 ± 0.2‰ for antennae tissue and 0.1 ± 0.2‰ δ13C for leg tissues, whereas for δ15N, no significant difference between tissues was observed. There was no significant effect of lobster size or sex, though we did observe interactions between month and tissue type, indicating that differences may be seasonal. Importantly, the detected range of isotopic variability between tissues is within the range of uncertainty used for discrimination factors in isotopic Bayesian modelling of 0‰–1.0‰ for δ13C and 3.0‰–4.0‰ for δ15N. Conclusions: We show that S. verreauxi can be sampled non‐lethally with mathematical corrections applied for δ13C, whereas any tissue is suitable for δ15N. Our results indicate that a walking leg is most favourable and would also be the least intrusive for the lobster. The application of non‐lethal sampling provides avenues for the contribution of citizen science to understanding lobster food webs and to undertake fieldwork in ecologically sensitive areas such as marine reserves. [ABSTRACT FROM AUTHOR]

Published
2023
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36. The BRUVs workshop – An Australia-wide synthesis of baited remote underwater video data to answer broad-scale ecological questions about fish, sharks and rays

Author

Harvey, Euan S., McLean, Dianne L., Goetze, Jordan S., Saunders, Benjamin J., Langlois, Tim J., Monk, Jacquomo, Barrett, Neville, Wilson, Shaun K., Holmes, Thomas H., Ierodiaconou, Daniel, Jordan, Alan R., Meekan, Mark G., Malcolm, Hamish A., Heupel, Michelle R., Harasti, David, Huveneers, Charlie, Knott, Nathan A., Fairclough, David V., Currey-Randall, Leanne M., Travers, Michael J., Radford, Ben T., Rees, Matthew J., Speed, Conrad W., Wakefield, Corey B., Cappo, Mike, and Newman, Stephen J.

Published
2021
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38. Effects of human footprint and biophysical factors on the body‐size structure of fished marine species

Author

Bosch, Nestor E., primary, Monk, Jacquomo, additional, Goetze, Jordan, additional, Wilson, Shaun, additional, Babcock, Russell C., additional, Barrett, Neville, additional, Clough, Jock, additional, Currey‐Randall, Leanne M., additional, Fairclough, David V., additional, Fisher, Rebecca, additional, Gibbons, Brooke A., additional, Harasti, David, additional, Harvey, Euan S., additional, Heupel, Michelle R., additional, Hicks, Jamie L., additional, Holmes, Thomas H., additional, Huveneers, Charlie, additional, Ierodiaconou, Daniel, additional, Jordan, Alan, additional, Knott, Nathan A., additional, Malcolm, Hamish A., additional, McLean, Dianne, additional, Meekan, Mark, additional, Newman, Stephen J., additional, Radford, Ben, additional, Rees, Matthew J., additional, Saunders, Benjamin J., additional, Speed, Conrad W., additional, Travers, Michael J., additional, Wakefield, Corey B., additional, Wernberg, Thomas, additional, and Langlois, Tim J., additional

Published
2021
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39. Residency and movement patterns of adult Port Jackson sharks (Heterodontus portusjacksoni) at a breeding aggregation site

Author

Bass, Nathan Charles, Day, Joanna, Guttridge, Tristan L., Mourier, Johann, Knott, Nathan A., Vila Pouca, Catarina, Brown, Culum, Bass, Nathan Charles, Day, Joanna, Guttridge, Tristan L., Mourier, Johann, Knott, Nathan A., Vila Pouca, Catarina, and Brown, Culum

Abstract

Examining the movement ecology of mesopredators is fundamental to developing an understanding of their biology, ecology and behaviour, as well as the communities and ecosystems they influence. The limited research on the residency and movements of benthic marine mesopredators has primarily used visual tags, which do not allow for the efficient and accurate monitoring of individual space use. In this study, the authors investigated the residency and movement patterns of Port Jackson sharks Heterodontus portusjacksoni (Meyer 1793) at a breeding aggregation site in Jervis Bay, south-eastern Australia, using passive acoustic telemetry to further our understanding of the movement ecology of these important mesopredators. Between 2012 and 2014, individuals were tagged with acoustic transmitters, and their residency and movements within the bay were monitored for up to 4 years. H. portusjacksoni showed strong preferences for particular reefs within and between breeding seasons. Males had significantly higher residency indices at their favoured sites relative to females, suggesting that males may be engaging in territorial behaviour. Conversely, female H. portusjacksoni exhibited higher roaming indices relative to males indicating that females may move between sites to assess males. Finally, H. portusjacksoni showed temporal variation in movements between reefs with individuals typically visiting more reefs at night relative to the day, dusk and dawn corresponding with their nocturnal habits.

Published
2021
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40. Increased connectivity and depth improve the effectiveness of marine reserves

Author

Goetze, Jordan S., primary, Wilson, Shaun, additional, Radford, Ben, additional, Fisher, Rebecca, additional, Langlois, Tim J., additional, Monk, Jacquomo, additional, Knott, Nathan A., additional, Malcolm, Hamish, additional, Currey‐Randall, Leanne M., additional, Ierodiaconou, Daniel, additional, Harasti, David, additional, Barrett, Neville, additional, Babcock, Russell C., additional, Bosch, Nestor E., additional, Brock, Danny, additional, Claudet, Joachim, additional, Clough, Jock, additional, Fairclough, David V., additional, Heupel, Michelle R., additional, Holmes, Thomas H., additional, Huveneers, Charlie, additional, Jordan, Alan R., additional, McLean, Dianne, additional, Meekan, Mark, additional, Miller, David, additional, Newman, Stephen J., additional, Rees, Matthew J., additional, Roberts, Kelsey E., additional, Saunders, Benjamin J., additional, Speed, Conrad W., additional, Travers, Michael J., additional, Treml, Eric, additional, Whitmarsh, Sasha K., additional, Wakefield, Corey B., additional, and Harvey, Euan S., additional

Published
2021
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42. Continental‐scale acoustic telemetry and network analysis reveal new insights into stock structure

Author

Lédée, Elodie J. I., primary, Heupel, Michelle R., additional, Taylor, Matthew D., additional, Harcourt, Robert G., additional, Jaine, Fabrice R. A., additional, Huveneers, Charlie, additional, Udyawer, Vinay, additional, Campbell, Hamish A., additional, Babcock, Russell C., additional, Hoenner, Xavier, additional, Barnett, Adam, additional, Braccini, Matias, additional, Brodie, Stephanie, additional, Butcher, Paul A., additional, Cadiou, Gwenael, additional, Dwyer, Ross G., additional, Espinoza, Mario, additional, Ferreira, Luciana C., additional, Fetterplace, Lachlan, additional, Fowler, Anthony, additional, Harborne, Alastair R., additional, Knott, Nathan A., additional, Lowry, Michael, additional, McAllister, Jaime, additional, McAuley, Rory, additional, Meekan, Mark, additional, Mills, Kade, additional, Peddemors, Victor M., additional, Pillans, Richard, additional, Semmens, Jayson, additional, Smoothey, Amy F., additional, Speed, Conrad, additional, Stehfest, Kilian, additional, Meulen, Dylan, additional, and Simpfendorfer, Colin A., additional

Published
2021
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45. Coexisting with sharks: a novel, socially acceptable and non-lethal shark mitigation approach

Author

Adams, Kye, Gibbs, Leah Maree, Knott, Nathan A, Broad, Allison, Hing, Martin, Taylor, Matthew, Davis, Andrew R, Adams, Kye, Gibbs, Leah Maree, Knott, Nathan A, Broad, Allison, Hing, Martin, Taylor, Matthew, and Davis, Andrew R

Abstract

Conflict between humans and large predators is a longstanding challenge that can present negative consequences for humans and wildlife. Sharks have a global distribution and are considered to pose a potential threat to humans; concurrently many shark species are themselves threatened. Developing strategies for coexistence between humans and this keystone group is imperative. We assess blimp surveillance as a technique to simply and effectively reduce shark encounters at ocean beaches and determine the social acceptance of this technique as compared to an established mitigation strategy—shark meshing. We demonstrate the suitability of blimps for risk mitigation, with detection probabilities of shark analogues by professional lifeguards of 0.93 in ideal swimming conditions. Social surveys indicate strong social acceptance of blimps and preference for non-lethal shark mitigation. We show that continuous aerial surveillance can provide a measurable reduction in risk from sharks, improving beach safety and facilitating coexistence between people and wildlife.

Published
2020

46. Seagrass canopies and the performance of acoustic telemetry: Implications for the interpretation of fish movements

Author

Swadling, Daniel, Knott, Nathan A, Rees, Matthew, Pederson, Hugh, Adams, Kye, Taylor, Matthew, Davis, Andrew R, Swadling, Daniel, Knott, Nathan A, Rees, Matthew, Pederson, Hugh, Adams, Kye, Taylor, Matthew, and Davis, Andrew R

Abstract

© 2020 The Author(s). Background: Acoustic telemetry has been used with great success to quantify the movements of marine fishes in open habitats, however research has begun to focus on patterns of movement and habitat usage within more structurally complex habitats. To date, there has been no detailed assessment of the performance of acoustic telemetry within seagrass, which forms a crucial nursery and foraging habitat for many fish species globally. Information on the detection range of acoustic receivers within seagrass is essential to guide receiver array design, particularly positioning systems. Here, we compare detection ranges for transmitters (Vemco V7) within and above the seagrass to determine impacts on the performance of a Vemco Positioning System (VPS). We also investigate the influence of environmental conditions (i.e. wind, time of day, background noise, atmospheric pressure and depth) on detection probability. Results: The performance of the VPS declined dramatically when the transmitters were positioned within the seagrass (positional accuracy = 2.69 m, precision = 0.9 m, system efficiency (i.e. the proportion of successful positions) = 5.9%) compared to above the canopy (positional accuracy = 2.21 m, precision = 0.45 m, system efficiency = 30.9%). The reduction in VPS efficiency when transmitters were within seagrass was caused by a decline in the detection range of receivers (range of 50% detections) from 85 to 40 m, as this limited the ability of the three receivers to simultaneously detect transmissions. Additionally, no detections were recorded for the transmitters within seagrass at a distance greater than 150 m from the receiver. Increasing wind speed from 0 to 50 km h-1 correlated with a 15% reduction in detections while detection probability decreased from 0.8 during the day to 0.55 at night, due to higher in-band noise (69 kHz). Conclusions: Our findings demonstrate that tagged fish ensconced within seagrass are unlikely to be detected by

Published
2020

48. Effects of human footprint and biophysical factors on the body‐size structure of fished marine species.

Author

Bosch, Nestor E., Monk, Jacquomo, Goetze, Jordan, Wilson, Shaun, Babcock, Russell C., Barrett, Neville, Clough, Jock, Currey‐Randall, Leanne M., Fairclough, David V., Fisher, Rebecca, Gibbons, Brooke A., Harasti, David, Harvey, Euan S., Heupel, Michelle R., Hicks, Jamie L., Holmes, Thomas H., Huveneers, Charlie, Ierodiaconou, Daniel, Jordan, Alan, and Knott, Nathan A.

Subjects
FISH populations, FACTOR structure, BYCATCHES, OCEAN temperature, MARINE parks & reserves, SIZE of fishes, FISH declines, FISHERIES
Abstract

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Published
2022
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49. A field and video annotation guide for baited remote underwater stereo‐video surveys of demersal fish assemblages

Author

Langlois, Tim, primary, Goetze, Jordan, additional, Bond, Todd, additional, Monk, Jacquomo, additional, Abesamis, Rene A., additional, Asher, Jacob, additional, Barrett, Neville, additional, Bernard, Anthony T. F., additional, Bouchet, Phil J., additional, Birt, Matthew J., additional, Cappo, Mike, additional, Currey‐Randall, Leanne M., additional, Driessen, Damon, additional, Fairclough, David V., additional, Fullwood, Laura A. F., additional, Gibbons, Brooke A., additional, Harasti, David, additional, Heupel, Michelle R., additional, Hicks, Jamie, additional, Holmes, Thomas H., additional, Huveneers, Charlie, additional, Ierodiaconou, Daniel, additional, Jordan, Alan, additional, Knott, Nathan A., additional, Lindfield, Steve, additional, Malcolm, Hamish A., additional, McLean, Dianne, additional, Meekan, Mark, additional, Miller, David, additional, Mitchell, Peter J., additional, Newman, Stephen J., additional, Radford, Ben, additional, Rolim, Fernanda A., additional, Saunders, Benjamin J., additional, Stowar, Marcus, additional, Smith, Adam N. H., additional, Travers, Michael J., additional, Wakefield, Corey B., additional, Whitmarsh, Sasha K., additional, Williams, Joel, additional, and Harvey, Euan S., additional

Published
2020
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