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Shovelnose Rays (Rajiformes)

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Shovelnose Rays (Rajiformes) I & I NSW WILD FISHERIES RESEARCH PROGRAM Shovelnose Rays (Rajiformes) EXPLOITATION STATUS UNDEFINED Eastern shovelnose ray is by far the most significant species in the catch of this group – research underway should improve biological knowledge for this species. SCIENTIFIC NAME STANDARD NAME COMMENT Constitutes the majority of the catch of this Aptychotrema rostrata eastern shovelnose ray group. There are minor landings of this species Rhynchobatus australiae whitespotted guitarfish from northern NSW. The small catches of this species are often Trygonorrhina fasciata eastern fiddler ray discarded. Glaucostegus typus giant shovelnose ray Caught infrequently. Rhina ancylostoma shark ray Caught infrequently. Rhynchobatus australiae Image © Bernard Yau Background Eastern shovelnose rays grow to a maximum Between 100 and 150 t of ‘fiddler’ rays are length of about 100 cm and weight of about landed annually in NSW. The bulk of the 4 kg while fiddler rays reach 120 cm and about catch (estimated 75%) consists of the eastern 10 kg. The whitespotted guitarfish can attain shovelnose ray (Aptychotrema rostrata), with 300 cm in length and weigh more than 200 kg. smaller quantities (~ 20%) of the eastern fiddler ray (Trygonorrhina fasciata) and occasional The biology of the eastern shovelnose ray in landings of the large whitespotted guitarfish Moreton Bay has been studied. Both sexes (Rhynchobatus australiae), the giant shovelnose matured at around 60 cm in length, and the ray (Glaucostegus typus) and the shark ray females were found to breed annually with (Rhina ancylostoma). large specimens giving birth in the summer to as many as 18 young. New-born young are The shovelnose and fiddler rays are endemic about 20 cm long. There is little biological to the southern Queensland and NSW coasts information available for the fiddler ray (likely (between latitudes 27° and 36° S) while the to have a similar reproductive cycle to the guitarfish ranges from northern NSW through shovelnose ray) or the whitespotted guitarfish. the tropics to southern Japan. All species mainly inhabit inshore smooth sandy substrates in depths less than 100 m and almost all the catch is taken by trawlers. STATUS OF FISHERIES RESOURCES IN NSW, 2008/09 SHOVELNOSE RAYS | P 283 WILD FISHERIES RESEARCH PROGRAM The commercial catch is taken almost totally by Historical Landings of Shovelnose Rays the Ocean Trawl Fishery. Significant numbers of shovelnosed rays are also taken by recreational 150 anglers. The commercial landings have been relatively stable at around 100 to 150 t since the mid 1990s when ‘fiddler/banjo shark’ 100 and ‘shovelnose/sand shark’ were first given separate species categories on commercial catch recording forms. Landings (t) 50 The stock status of all species is uncertain and the species composition of the catch needs to be more accurately determined. New 0 catch reporting forms introduced in July 2009 90/91 92/93 94/95 96/97 98/99 00/01 02/03 04/05 06/07 08/09 require catches of all species to be separately Financial Year recorded. No stock assessment is available for Commercial landings (including available historical shovelnosed or fiddler rays in NSW waters. records) of shovelnose rays for NSW from 1990/91 to Length frequency data are available for the 2008/09 for all fishing methods. common species from Fisheries Research Vessel Kapala trawl surveys of inshore grounds in the 1990s. Landings by Commercial Fishery of Shovelnose Additional Notes Rays Ocean Trap and Line • The majority of the commercial catch is Ocean Prawn Trawl (Primary Species) eastern shovelnose ray mainly from ocean Fish Trawl (Primary Species) prawn trawling and ocean fish trawling. Shovelnose rays are also taken in significant 150 quantities by recreational fishers. • Preliminary indications are that the stock of eastern shovelnose rays is more or less stable, 100 but mortality rates are yet to be estimated. Landings (t) • Female shovelnose rays have up to 18 50 embryos and move into shallower waters over the summer months to give birth (they 0 are not susceptible to the trawl fishery during 97/98 99/00 01/02 03/04 05/06 07/08 this stage but are taken by recreational Financial Year fishers). Reported landings of shovelnose rays by NSW commercial fisheries from 1997/98. Fisheries which • These species are difficult to monitor after contribute less than 2.5% of the landings are excluded landing because fishers head and fin them. for clarity and privacy. Onboard identification of the different species is straightforward because they have distinct morphologies. Catch Rereational Catch of Shovelnose Rays The annual recreational harvest of shovelnose rays in NSW is likely to lie between 20 and 50 t. This estimate is based upon the results of the offsite National Recreational and Indigenous Fishing Survey (Henry and Lyle, 2003) and onsite surveys undertaken by I & I NSW. P 284 | SHOVELNOSE RAYS STATUS OF FISHERIES RESOURCES IN NSW, 2008/09 Catch Per Unit Effort Information of Shovelnose Further Reading Rays Harvested by Fish Trawling in NSW Ferrell, D. (1993). Pilot study on the feasibility of 1.0 ageing snapper, rubberlip morwong, red gurnard and banjo (fiddler) rays. Unpublished report. Cronulla, NSW Fisheries Research Institute: 22pp. 0.8 Henry, G.W. and J.M. Lyle (2003). The National Recreational and Indigenous Fishing Survey. Final 0.6 Report to the Fisheries Research & Development Corporation and the Fisheries Action Program 0.4 Project FRDC 1999/158. NSW Fisheries Final Report Relative Catch Rate Series No. 48. 188. pp Cronulla, NSW Fisheries. 0.2 Kyne, P.M. and M.B. Bennett (2002). Diet of the eastern shovelnose ray, Aptychotrema rostrata (Shaw & 0.0 Nodder, 1794), from Moreton Bay, Queensland, 93/94 98/99 03/04 08/09 Australia. Marine and Freshwater Research 53 (3): Financial Year 679-686. Catch rates of shovelnose rays harvested using fish Kyne, P.M. and M.B. Bennett (2002). Reproductive trawling for NSW. Two indicators are provided: (1) median biology of the eastern shovelnose ray, Aptychotrema catch rate (lower solid line); and (2) 90th percentile of the catch rate (upper dashed line). Note that catch rates rostrata (Shaw & Nodder, 1794), from Moreton are not a robust indicator of abundance in many cases. Bay, Queensland, Australia. Marine and Freshwater Caution should be applied when interpreting these Research 53 (2): 583-589. results. Last, P.R. and J.D. Stevens (2009). Sharks and Rays of Australia 2nd Edition. Melbourne, CSIRO. Marshall, L.J., W.T. White and I.C. Potter (2007). Length Frequency of Eastern Shovelnose Ray Reproductive biology and diet of the southern fiddler ray, Trygonorrhina fasciata (Batoidea : Rhinobatidae), an important trawl bycatch species. 0.14 1989/90−1995/96 Marine and Freshwater Research 58 (1): 104-115. n = 6310 0.12 0.10 Please visit the CSIRO website, 0.08 http://www.marine.csiro.au/caab/ and search for the species code (CAAB) 37 027009, 37 026001, 0.06 Proportion 37 027006 and 37 026002, common name or 0.04 scientific name to find further information. Please note that common names have been adopted from 0.02 Last and Stevens (2010) and may differ to those 0.00 contained on the CAAB website. 20 40 60 80 100 TL (cm) The length distribution of eastern shovelnose ray caught during trawl surveys by the Fisheries Research Vessel Kapala was comprised mainly of rays between 20 and 100 cm total length (TL). There is no minimum legal length for shovelnose rays in NSW. © State of New South Wales through Industry and Investment NSW 2010. You may copy, distribute and otherwise freely deal with this publication for any purpose, provided that you attribute Industry and Investment NSW as the owner. Disclaimer: The information contained in this publication is based on knowledge and understanding at the time of writing (April 2010). However, because of advances in knowledge, users are reminded of the need to ensure that information upon which they rely is up to date and to check currency of the information with the appropriate officer of Industry and Investment NSW or the user’s independent adviser. SHOVELNOSE RAYS | P 285 WILD FISHERIES RESEARCH PROGRAM P 286 | SHOVELNOSE RAYS.
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