Management of Humphead - PDF document

Management of Humphead Table of Contents Introduction.................................................................................................................................3 Life History.................................................................................................................................3 t and movement........................................................................................3 Population Density and Abundance........................................................................................4 Biology....................................................................................................................................4 Mortality......................................................................................................................................5 State.........................................................................................................................................5 Commonwealth.......................................................................................................................6 Management Arrangements for the Coral Sea Fishery...............................................................6 Catch........................................................................................................................................6 Characteristics of the Coral Sea Fishery.................................................................................7 Industry initiatives...................................................................................................................7 Spatial closures........................................................................................................................7 Reporting and Monitoring.......................................................................................................7 Summary.....................................................................................................................................7 References...................................................................................................................................8 2 Introduction Humphead Maori Wrasse (Cheilinus undulatus) is the largest member of the wrasse family, Labridae, and one of the largest reef associated fish (excluding sharks) in the world. The species occurs in relatively low densities generally down to 100 metres depth; has a modest life span (30 years) compared to temperate or deeper water species; and has relatively high Humphead Maori Wrasse is a highly prized food fish in some countries, and has been heavily exploited for the live reef fish trade through its core range in southeastern Asia (Sadovy et al. 2003). Fishery-dependent and trade-related data suggest a 10-fold or greater decline over the last 10 to 15 years in heavily exploited areas such as Malaysia, Indonesia and the Philippines. Much of the catch for the live fish trade in these source countries is of small, juvenile fish (Russell, 2004). Humphead Maori Wrasse has been listed on the International Union for Conservation of Nature (IUCN) Red List since 1996, initially as Vulnerable and since 2004 as Endangered. In 2005 it was listed in Appendix II of the Convention on International Trade of Endangered In Australia, Humphead Maori Wrasse has historically been subject to some commercial fishing pressure, primarily in state-managed fisheries. However, the species has been protected under State legislation since 1998 in Western Australia, and since 2003 in Queensland. The species is not protected in the Northern Territory, however catches are thought to be negligible. In Commonwealth-managed fisheries, catches are extremely low, with less than 50 animals exported per year for the past 10 years. These animals have been taken by the aquarium sector of the Coral Sea Fishery (CSF) and are sold to aquaria around the world for public display and educational purposes. Whilst the current rate of exploitation of Humphead Maori Wrasse in the CSF is considered negligible (Choat pers comm., Bellwood pers comm.), the CITES listing requires member nations, including Australia, to ensure the trade of Humphead Maori Wrasse is controlled, so as not to jeopardise the survival of the species. Australia’s obligations under CITES are met Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). For this species to be exported, the EPBC Act requires a non-detriment finding to be made. This paper outlines management arrangements that have been developed for Humphead Maori Wrasse that seek to ensure the continued sustainable take of this species in the CSF. This paper forms AFMA’s submission to the Department of Environment, Water, Heritage and the Arts to inform the decision on a CITES non-detriment finding. Life History Distribution, habitat and movement Humphead Maori Wrasse is found throughout the tropical Indo-Pacific, from the Red Sea and the coast of east Africa, to the central Pacific; south from Japan to New Caledonia and the Tuamoto Islands, north to the Ryukyu Islands (Sadovy et al. 2003, Figure 1). In Australia, Humphead Maori Wrasse occur on offshore reefs from north-western to north eastern Australia, including the Great Barrier Reef (Pogonoski et al. 2002). Post-settlement, Humphead Maori Wrasse typically inhabit area with seagrass and hard corals. Juveniles also favour similar areas, such as coral-rich lagoon reefs, seagrass beds, murky outer river areas with patch reefs; shallow sandy areas adjacent to coral reef lagoons, and inshore mangrove and seagrass areas. Adults are more common offshore than inshore, 3 occupying steep outer reef slopes, reef drop-offs, reef tops, channel slopes, reef passes, and lagoon reefs to at least 100 metres (various authors cited in Russell 2004). Humphead Maori Wrasse feed primarily on crustaceans, molluscs, fish and echinoderms (Choat et al, 2006). Figure 1. Distribution map of Humphead Maori Wrasse, Cheilinus undulates. Source: AquaMaps GNIF OBIS (expert reviewed) in Fishbase.org, 2010. Apart from spawning aggregations, Humphead Maori Wrasse are generally solitary, travelling across the reef by day and sheltering in reef caves and under coral ledges at night. Occasionally groups of several females may be observed, however males are seldom found Spawning aggregations can vary in their size and timing, depending on location, but may form daily during most months of the year (Colin 2010). Whilst limited, the available information suggests individuals may travel kilometres from their home range to participate in these spawning aggregations (Sadovy Population Density and Abundance Densities of Humphead Maori Wrasse rarely exceed 20 fish per hectare in their preferred habitats of outer reefs (Russell, 2004), but are generally not more than 10 fish per hectare The population density of adult Humphead Maori Wrasse in the CSF is thought to be between three and five adults per hectare (Choat, 2010). A separate estimate, using data from the CSF and Great Barrier Reef, suggests the population occurring on reefs typically fished by CSF Aquarium sector operators is between 50,000 and 100,000 adult Humphead Maori Wrasse (Bellwood, pers comm.). Biology Humphead Maori Wrasse is a protogynous hermaphrodite. The majority of animals in the population develop first as females, reaching sexual maturity at an age of approximately five years (approximately 35-50cm). They then develop as males at an age of approximately nine years (approximately 70cm); at this time their growth rates also increase significantly (from 2006). Humphead Maori Wrasse are thought to reach a maximum age of between 25 and 30 years. 4 The current and proposed take of Humphead Maori Wrasse in the CSF is extremely low and unlikely to be detectable in populations. The methods used to capture this species are also highly selective, with little impact on other species and the marine environment. Humphead Maori Wrasse taken by the Aquarium sector have had a chance to breed and large areas of habitat have already been closed to fishing since 1982 through marine reserves; these areas provide refuge for Humphead Maori Wrasse and many other species. These factors contribute to the sustainability of the fishery. The continued take of Humphead Maori Wrasse by the CSF Aquarium sector has an important role to play internationally in raising awareness of this species importance, its depleted status and the need for effective management around the world. References Anderson C, Clarke K, Higgs H and Ryan S., 2005. Ecological assessment of the Queensland coral reef fin fish fishery; A report to the Australian Government Department of Environment and Heritage on the ecologically sustainable management of a multi-species line fishery in a coral reef environment. Queensland Government Department of Primary Industries. 149 pp Colin, P.R., 2010. Aggregation and spawning behaviour of the humphead wrasse Cheilinus undulates (Pisces: Labridae): general aspects of spawning behaviour. Journal of Fish Biology; Choat, J.H., Davies, C.R., Ackerman, J.L. and Mapstone, B.D., 2006. Age structure and growth in a large teleost, Cheilinus undulates, with a review of size distribution in labrid fishesMarine Ecology Progress Series, 318, pp.237-246. Froese, R. and Pauly, D. (eds.), 2000, FishBase 2000, Concepts, design and data sources. xvii,344p. Los Banos, Laguna, Philippines, ICLARM. Pogonoski, J.J., Pollard, D.A. and Paxton, J.R. 2002. Conservation overview and action plan for Australian threatened and potentially threatened marine and estuarine fishes. Environment Russell, B. 2004. Cheilinus undulatusVersion 2010.3. www.iucnredlist.org . Downloaded on 8 September 2010. Sadovy, Y., Kulbicki, M., Labrosse, P., Letourneur, Y., Lokani, P. and Donaldson, T.J. 2003. The humphead wrasse, Cheilinus undulatus: synopsis of a threatened and poorly known giant Reviews in Fish Biology and Fisheries 13(3): 327–364. 8