Australian Coral Reef Society Inc.

Australian Coral Reef Society Inc. A society promoting scientific study of Australian Coral Reefs Address:

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ACRS Correspondence c/- Biological Sciences The University of Queensland St Lucia QLD 4072 (07) 3365 1686 (07) 3365 1655 [email protected]

To: Great Barrier Reef Marine Park Authority Assessments and Permissions Team PO Box 1379 Townsville QLD 4810 29 November 2015 RE: Comments on the Expansion of the Great Barrier Reef Marine Parks Shark Control Program Associated with application G33288.1 Dear Sir/Madam: The Australian Coral Reef Society is the professional organisation for coral reef scientists and managers in Australia and is focused on the study and protection of coral reefs. We have approximately 300 members and, since our inception in 1922, have played a prominent role in bringing major conservation issues to the attention of governments and the general public. The society regularly provides advice on marine issues to governments and agencies. The Australian Coral Reef Society would like to write in strong opposition to further deployment of nets and drumlines on the Great Barrier Reef. Since the inception of the Queensland Shark Control Program (QSCP) in 1962, there have been over 3300 large sharks killed. The sharks targeted in this program are apex predators on coral reef ecosystems, and serve a valuable and important role in population control of lower trophic levels (Estes et al. 2011). By removing these important animals, cascading effects will be felt on reefs along the GBR (see below). The efficacy of these procedures have been called into question before (Curtis et al. 2012), and should be addressed before additional impacts to the health of the GBR are felt. In particular there are 3 areas of main concern to the Australian Coral Reef Society: 1. The Mortality of Bycatch Bycatch is a fish or other marine species that is caught unintentionally while targeting certain species (e.g., sharks). According to the statistics released by the QSCP, over one-‐ third of bycatch on drum lines deployed for the Shark Control Program resulted in death President: Hon Secretary: Hon Treasurer:

Prof David Booth; Tel: 02 9514 4053; Fax: 02 9514 4079; Email: [email protected] 1 Dr O. Selma Klanten; Tel: 0417 341 941; Fax: 02 9514 4079; Email: [email protected] Dr Jennifer Donelson; Tel: 0402 062 046; Fax: 02 9514 4079; Email: [email protected]


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(Table 1). Furthermore, the condition of the bycatch animals released alive is unknown, and their ability to survive after release is likewise highly uncertain. Among the animals caught are federally protected species of turtles and fish. Listed species that have been caught as bycatch include EPBC listed vulnerable species of humpback whales, green, hawksbill and flatback turtles, and the Queensland sawfish. Additional animals that are listed as vulnerable on the IUCN red list that were caught include dugongs, dolphins, and rays. Table 1. Data collated from Tables 2-‐6 of the public information packet of the Great Barrier Reef Marine Parks Shark Control Program, associated with application G33288.1. Figures represent numbers of animals caught between a 10-‐year period (2005-‐2014) # Caught in # Caught on # Released Nets Drumlines Alive # Killed % Death Target Shark species 169 3198 NA 3367 100 Bycatch Sharks 38 165 184 19 9.4 Dolphin 9 4 5 8 61.5 Turtle 28 22 44 6 12.0 Dugong 4 1 1 4 80.0 Ray 213 40 150 103 40.7 Other 4 130 44 90 67.2 Total Bycatch 296 362 428 230 35.0 Total # Bycatch 658 % Death of Bycatch 34.95% In particular, dugongs are highly vulnerable to human impact due in part to low population sizes, slow individual and population growth rates, and long generation times (Marsh 2002). Dugong populations along the coast of Queensland, Australia, are found close to developed urban centres with significant industrial and coastal activity (Marsh and Lawler 2001a, 2001b). The total of dugong bycatch in the QSCP over the first 30 years of operation showed significant declines in dugong populations occurring along the entire developed Queensland coast, to approximately 3% of 1960 population levels (Marsh et al. 2001, 2005). While the netting techniques used at that time are no longer in use, dugongs have still been caught (5 in the last 10 years) and this catch has resulted in an 80% individual mortality rate. Percent mortality of bycatch has not decreased, causing great concern to ACRS (as seen in the figure to the left). While the total number of bycatch is decreasing, any mortality of President: Hon Secretary: Hon Treasurer:



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vulnerable species, given the lack of scientific rigor of this program, presents a problem that should be addressed. 2. The Loss of Apex Predators The importance of and concerns for the loss of apex predators along the GBR has been documented for the GBRMPA (Ceccarelli and Ayling 2010). Although drumlines are only deployed in areas with large coastal human populations, there are still significant impacts on shark populations as a whole due to the large home ranges of sharks (Robbins 2006). Worldwide, there have been notable cases of how the removal of apex predators (including the shark species targeted by the GBRMPA’s drumline program) has had detrimental indirect effects on marine ecosystems and human livelihoods. One example of this is the overfishing of large sharks in the northwest Atlantic that has been clearly linked to the collapse of the bay scallop fishery (Argopecten irradians) in North Carolina, as a result of absence of population control of cownose rays (Rhinoptera bonasus; Meyers et al. 2007). Other detrimental effects, such as increases in invasive species and Fig. 1 Data collected from the QSCP non-target catch data changes in carbon sequestration and reef from 2001-2014 biogeochemistry are all cascading effects that have been documented to occur with the removal of large predators (Estes et al. 2011). In addition, human removal of apex predators such as sharks changes the balance of predation risk in oceans, leading to a wide range of cascading effects through marine ecosystems (Madin et al. 2015). In coral reefs worldwide, fishing can also indirectly alter patterns of herbivory, leading to shifted benthic dynamics with the competitive advantage of reef-‐building corals and coralline algae diminished in concert with removal of large fish (Ruppert et al. 2013; Sandin et al. 2008). 3. Perception of the human-‐shark conflict While there has been no fatality on beachgoers in Queensland since the QSCP started, there remains no scientific evidence that this program is the cause of this trend. This latter point is of great concern to the members of our scientific society (ACRS). While the worldwide number of shark attacks has risen (Curtis et al. 2012), the number of beachgoers

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has also dramatically increased, making it difficult to know whether actual risk has changed over time. However, a very similar circumstance exists in California, from which we can glean valuable lessons. There, scientific analysis has clearly shown that although the number of shark attacks have increased, the individual attack risk has decreased by >91% over a 63 year period (Ferretti et al. 2015). Given the dramatic declines in sharks globally and in Queensland in particular (Robbins et al. 2006), it appears very likely that Queensland may have the same trend. The authors of the California study suggest that instead of using unproven methods, such as culling, promoting safer behaviour among ocean users, as well as research into behaviour and spatial distribution in sharks, are vastly more effective in preventing shark attacks than are culling programs. Importantly, these solutions avoid the unintentional environmental and economic impacts that further reductions of apex predators, as described above. While drumline fishing may reduce the perception of risk by Australian beachgoers, there is no credible scientific evidence to back this perception (if, indeed, it exists). We therefore implore GBRMPA to search for alternatives that will not have such negative repercussions on the very ecosystem that you are entrusted to protect. What about alternatives to the Queensland Shark Control Program? ACRS recognizes that there are programs in place to limit the impact of bycatch (e.g., Marine Animal Release Teams; MART). While these programs are commendable, the unproven value of culling, compounded with >200 non-‐target species killed within the last 10-‐years demands a review of the entire program. A viable alternative to culling is implementing the Shark Spotters Program similar to that developed in South Africa (Oelofse and Kamp 2006; http://sharkspotters.org.za/). In this program, 4 warning levels (coloured flags) are positioned along the beach, and spotters are positioned around the coastline to monitor conditions. If a shark is spotted, an alarm is raised, and the beach is evacuated. It is also important to note that stinger nets are placed in populated areas in Queensland beaches year-‐round, and during stinger seasons in others (http://www.qldbeaches.com/stingers.html). The risks of shark attacks inside these enclosures are negligible, and an alternative to culling is establishing more swimming enclosure areas as well as deploying them year-‐round.




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We would be more than happy to offer our scientific expertise in a continuing dialogue about this issue with the GBRMPA. Kind regards,

Professor David Booth ACRS President




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References: Ceccarelli, D., & Ayling, T. (2010). Role, importance and vulnerability of top predators on the Great Barrier Reef – A review (pp. 1–150). Curtis, T., Bruce, B. D., Cliff, G., Dudley, S. F. J., Peter, A., Kock, A. A., Lea, R. N., et al. (2011). Responding to the Risk of White Shark Attack Updated Statistics , Prevention , Control Methods, and Recommendations. Global Perspectives on the Biology and Life History of the Great White Shark (pp. 477–510). Estes, J. A, Terborgh, J., Brashares, J. S., Power, M. E., Berger, J., Bond, W. J., Carpenter, S. R., et al. (2011). Trophic downgrading of planet Earth. Science (New York, N.Y.), 333(6040), 301–6. doi:10.1126/science.1205106 Ferretti, F., Jorgensen, S., Chapple, T. K., De Leo, G., & Micheli, F. (2015). Reconciling predator conservation with public safety. Frontiers in Ecology and the Environment, 13(8), 412–417. doi:10.1890/150109 Madin, E. M. P., Dill, L. M., Ridlon, A. D., Heithaus, M. R., & Warner, R. R. (2015). Human activities change marine ecosystems by altering predation risk. Global Change Biology, n/a–n/a. doi:10.1111/gcb.13083 Marsh H (2002) Dugong status report and action plans for countries and territories. UNEP Early Warning and Assessment Report Series. Marsh H, De'ath G, Gribble N & Lane B (2001). Shark control records hindcast serious decline in dugong numbers on the urban coast of Queensland. GBRMPA Research Publication 70, 1-‐24. Great Barrier Reef Marine Park Authority. Marsh H & Lawler IR (2001a). Dugong distribution and abundance in the northern Great Barrier Reef Marine Park, November 2000. Draft Report to the Great Barrier Reef Marine Park Authority. Townsville, Australia. Marsh H & Lawler IR (2001b). Dugong distribution and abundance in the southern Great Barrier Reef Marine Park and Hervey Bay: Results of an Aerial Survey in October-‐ December 1999. GBRMPA Research Publication 70. Great Barrier Reef Marine Park Authority. Townsville, Australia. Marsh H, De'ath G, Gribble N & Lane B (2005). Historical marine population estimates: triggers or targets for conservation? The dugong case study. Ecological Applications, 15: 481-‐492. McCauley, D. J., Pinsky, M. L., Palumbi, S. R., Estes, J. a., Joyce, F. H., & Warner, R. R. (2015). Marine defaunation: Animal loss in the global ocean. Science, 347(6219), 1255641– 1255641. doi:10.1126/science.1255641 Meyers, R. A., Baum, J. K., Shepherd, T. D., Powers, S. P., & Peterson, C. H. (2007). Cascading effects of the loss of apex predatory sharks from a coastal ocean. Science, 315(March), 1846–1850. Oelofse G, Kamp Y (2006) Shark spotting as a water safety program in Cape Town. In Nel. D C and Peschak T P (eds). Finding a balance: White shark conservation and recreational




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safety in the inshore waters of Cape Town, South Africa: proceedings of a specialist workshop. WWF South Africa Report Series –2006/Marine/001.

Robbins, W. D., Hisano, M., Connolly, S. R., & Choat, J. H. (2006). Ongoing collapse of coral-‐ reef shark populations. Current Biology : CB, 16(23), 2314–9. doi:10.1016/j.cub.2006.09.044 Ruppert, J. L. W., Travers, M. J., Smith, L. L., Fortin, M.-‐J., & Meekan, M. G. (2013). Caught in the middle: combined impacts of shark removal and coral loss on the fish communities of coral reefs. PloS One, 8(9), e74648. doi:10.1371/journal.pone.0074648 Sandin, S. a, Smith, J. E., Demartini, E. E., Dinsdale, E. a, Donner, S. D., Friedlander, A. M., Konotchick, T., et al. (2008). Baselines and degradation of coral reefs in the Northern Line Islands. PloS One, 3(2), e1548. doi:10.1371/journal.pone.0001548

