shark recaptures - department of primary industries€¦ · mako shark s235650 05/12/2010...
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22 BlueWater Boats & Sportsfishing
ThroughouT spring and early summer, a number of tagged sharks were recaptured along the NSW coast.
Interestingly, the shark that had apparently travelled the least had spent the longest time at liberty. Lockout of Botany Bay GFC first tagged this mako south of Sydney in September 2009 using a circle-hook-rigged bonito. The boat Razorback, fishing only 14 nautical miles away, east of Botany Bay, recaptured it 420 days later in November 2010. It is likely that the fish had made a much more significant movement over the time-period. Makos are like many other pelagic fish species in that they respond to the influence of the East Australian Current and the changing location of food supply.
Two other mako sharks recaptured 69 and 65 days after first being tagged in September and December had moved 58 and 53 nautical miles south respectively.
Another mako shark holds the record for the longest time at liberty for all species tagged under the I&I NSW Game Fish Tagging Program. This mako was first tagged off Port
Macquarie, NSW in September 1987 and was recaptured in August 1999 off Port Hacking, NSW – a straight-line distance of 174 nautical miles. The fish was estimated at 15kg when first tagged and weighed, and
101kg when recaptured almost 12 years later. This change is apparently within normal ranges for this species and d e m o n s t r a t e s their relatively slow growth rate.
The record-breaking mako was reported to have only 15mm of the tag still showing as the shark’s
considerable growth had covered the remainder of the tag. There was also a second tag in the fish, which, unfortunately, the card was never returned for so we don’t have the details. However, from our deductions (by looking at the tag’s number, then checking details for the tags before and after) the mako was likely to have received the second tag in 1999 from a boat fishing out of Sydney.
A blue shark tagged by Newcastle & Port Stephens GFC Boat Rackem Up during the NSW Interclub competition in February 2010 was recaptured in October, showing a southern movement of 88 nautical miles. The fish was estimated to be approximately 70kg on release and 75kg on recapture 280 days later.
This is a timely reminder to ask everyone to check their boats for completed tag cards and send them through to the Game Fish Tagging Program (even if they are several years old!). We are still awaiting crucial first-release information on a number of recaptures reported to us in the past three months.
The Industry & Investment NSW (I&I NSW) Game Fish Tagging Program issues tags to individuals and fishing clubs using funds from the NSW Recreational Fishing Trust. If you would like to participate in the program, please phone (02) 9527 8411 or email: gamefish.tagging@industry.nsw.gov.au
– Phil BoltonFisheries Manager, Tagging
I&I NSW
News aNd eveNts affectiNg gamefishermeNNewsliNes
shark recaptures
Species Tag Number Rel. Date Rel. LocationEst Rel. Length/Weight
Recap.Date Recap. LocationEst. Recap.
Length/Weight
Days at Liberty
Approx. Distance
Moved (NM)Map Ref.
Mako Shark S236607 20/09/2009Stanwell Park
Canyons (NSW)50kg 14/11/2010
Botany Bay East (NSW)
185cm/68.5kg
420 14 MS 1
Mako Shark S238142 19/09/2010Stanwell Park
Canyons (NSW)– 27/11/2010
Jervis Bay East (NSW)
164cm/55 kg 69 58 MS 2
Mako Shark S235650 05/12/2010Shellharbour East (NSW)
140cm/ 35kg
08/02/2011Lake Tabourie
East (NSW)110cm/10 kg 65 53 MS 3
Blue Shark S204142 28/02/2010Port Stephens
East (NSW)250cm/
70kg05/12/2010
Stanwell ParkCanyons (NSW)
75kg 280 88 BS 1
This article is provided courtesy of BlueWater Boats & Sportsfishing magazine. It originally appeared in Issue 85, 2011
www.bluewatermag.com.au
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