TAGGING NEWS NUMBER 19 PUBLISHED JUNE 2006 RESULTS FROM 2005

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1 TAGGING NEWS The Tony and Lisette Lewis Foundation South Africa th Welcome to the 19 issue of the Tagging News. As you will see from our new-look cover, the Tagging Project has undergone some substantial changes over the past year! Firstly, during 2005 Sedgwick's Old Brown (Distell) announced that they would cease to fund the Tagging Project at the end of After 22 years of reliable and committed support, this news came as quite a shock! Nevertheless, we are extremely grateful to Distell (previously Sedgwick's Farmers Winery) for their past support and considerable financial contribution and wish them well in their future endevours. With sponsorship of the Tagging Project gone we (ORI) turned to WWF-SA for help. Fortunately WWF-SA was up to the challenge and through their efforts, and particularly those of Ms Paddy Walker, was able to secure funding for the continuation of the Tagging Project. ORI and WWF-SA are thus delighted to confirm that the Tony and Lisette Lewis Foundation South Africa (TLLF) have agreed to fund the Tagging Project for the next three years. As members of the Tagging Project probably know very little about the TLLF, we felt that it was appropriate to give the Foundation a brief introduction. The TLLF was created by a deed of trust by the late Anthony Calvert Lewis in His wife, the late Elizabeth Helen Lewis, gave her complete support to the project and both nominated the Foundation as the ultimate residual beneficiary of the estates. The purpose behind the establishment of the Foundation was fundamental to their underlying hope that the present and future generations of South Africans would not only enjoy the pleasures of the beauty of this land and its abundance of wildlife, but also provide encouragement and support for the proper care of domestic animals. In short the TLLF is structured to provide funding for all aspects of nature conservation and animal protection activities. Tony and Lisette passed away within nine months of each other and the Foundation was vested from the 30 April 1995, and shortly thereafter the trustees commenced setting up operations. This generous legacy of the Lewis family will enable the TLLF to make substantial and ongoing contributions to the country's conservation programmes. The ORI/WWF-SA Tagging Project conforms extremely well to the objectives of the TLLF which are as follows: To be proactive in supporting and furthering the development of conservation within the borders of South Africa. To increase the awareness of nature conservation to all South Africans, particularly the youth through the process of education. To support and develop programmes aimed at achieving a high level of public participation in conservation activities. To support research projects undertaken for the advancement of conservation. To build the fund's capital base over time to provide increased resources in order to further the above objectives. The ORI/WWF-SA Tagging Project thus looks forward to developing a successful and prosperous relationship with the TLLF. Our other big news is that our Tagging Officer Ms Elinor Bullen officially retired at the end of March 2006 after 22 years of loyal and dedicated service. Fortunately, as Elinor was not ready to hang up the gloves just yet, we have re-employed her on a one-year renewable contract basis. We are extremely grateful for her ongoing commitment as it will ensure that we can continue the project without having to down tools while we employ and train a new Tagging Officer. On the tagging front, 2005 was a reasonably good year with 7445 fish tagged and 467 recaptures reported (6.27%). A further 52 new taggers joined the project, bringing the total number of participants to 4243 since the project's inception in However, it is important to point out that only 345 members tagged one or more fish NUMBER 19 PUBLISHED JUNE 2006 RESULTS FROM 2005 Continued on page 2 Published by: Oceanographic Research Institute, P. O. Box 736, Durban, 4000, South Africa

2 Continued from page 1 during 2005 so there are still a large number of inactive resolve some of the confusion surrounding the common members out there! In order to ensure that any new names of bull and eagle rays, and a short article members that join the project are motivated to catch and describes how and what length to measure when tagging tag fish correctly and for the right reasons, we now fish. Interesting facts are brought to light about catface carefully scrutinize each new applicant and request a rockcod and ragged-tooth sharks and we share a letter of motivation before membership is granted and a number of exciting recaptures with you. tagging kit is supplied. However, please do not let this put We would like to express our sincere gratitude to the you off, if you are really keen and motivated we strongly TLLF and WWF-SA for providing funding the Tagging encourage you to join the project! Project and a big thank you to all of you - members of the In this edition of the Tagging News we bring you Dr Scotty tagging project, for your ongoing support and Kyle's perspective on the use of tagging data to manage contribution towards the wise use and conservation of the fishery at Kosi Bay. Dr Paul Cowley tells us about his our fish resources. We sincerely hope that you enjoy this innovative idea to use a cellphone number on fish tags to edition of the Tagging News and wish you tight lines and get better reporting of recaptured fish and Sabine happy tagging! Wintner gives us her annual update on tagging activities conducted by the Natal Sharks Board. We attempt to Bruce Mann, Elinor Bullen and Bernadine Everett Year New members Active members Fish tagged Species tagged PROGRESS TO DATE Recapture % Overall Maximum years free Maximum Km moved FISH TAGGED PER YEAR & PER ANGLER NUMBER OF FISH TAGGED PERCENT YEAR YEAR Average tagged Total fish tagged % FISH RECAPTURED PER YEAR NUMBER OF FISH TAGGED PER ANGLER NUMBER OF ANGLERS TREND IN ANNUAL MEMBERSHIP YEAR SPECIAL THANKS The Tagging Programme would like to thank the following company and individuals who gave us special support during the year 2005: Purglass for making the tagging billfish poles for 28 consecutive years. Roelf Venter for his assistance in fitting handles to the applicators. Generous donations from Arthur Cary, Gawie Du Toit, C.R.Maske & Garth Mc Gee. 2

3 MAJOR SPECIES TAGGED TO DATE ( ) Galjoen % FISH TAGGED ALONG THE SOUTHERN AFRICAN COAST IN 2005 Western Cape Cape West Coast Mozambique Dusky shark Zululand Dusky kob Other Copper shark Spotted gulleyshark Spotted grunter Garrick Shad White steenbras Southern Cape Eastern Cape Border Transkei Natal EXCITING RECAPTURES Bronze bream Giant sandshark Pachymetopon grande Rhynchobatus djiddensis 1543 tagged, 79 recaptured = 5.12% recapture rate 3744 tagged, 221 recaptured = 5.9% recapture rate Longest distance travelled 799 km. Longest distance travelled 320 km. Maximum days free 1465 (4 years) Maximum days free 1945 (5.33 years) Researchers working in the Tsitsikamma National Park in June A 42.3 kg giant sandshark was recently recaptured at Nyoni 2001 tagged a bronze bream of 370 mm FL. Remarkably this Rocks in Amanzimtoti. It was originally tagged four years earlier fish was recaptured (shot by a spear fisherman) off Treasure at Umhlanga Rocks when it weighed 10 kg. Thus during the Beach in KZN in June Unfortunately the fish was not 1533 days free, the sandshark grew by 840 mm in length, measured but during its 1465 days free (4 years) it had gained 32,3 kg and moved 56 km. travelled 799 km, which is a new record for this normally very resident species. Diamond ray White steenbras Gymnura natalensis Lithognathus lithognathus 2054 tagged, 13 recaptured = 0.6% recapture rate 3787 tagged, 199 recaptured = 5.25% recapture rate Longest distance travelled 1577 km. Longest distance travelled 620 km. Maximum days free 1890 (5.17 years) Maximum days free 2262 (6.2 years) A tagged diamond ray was recently recaptured at Mtwalume on Dr. Paul Cowley and his team, fishing in the Tsitsikamma the KZN South Coast. This ray was tagged 176 days previously National Park, tagged a white steenbras of 309 mm FL on 9 by Chris Fallows near Muizenberg in the Western Cape and October This fish was recaptured by Mr Norman Nel at had travelled an amazing distance of 1577 km before being Green Bay near Gonubie on 18 December In the 2262 recaptured and re-released again by Stanger angler Zahir days (6.2 years) at liberty the fish grew 591 mm and travelled Rowat. Out of 2054 diamonds rays tagged to date, only km. (0.6%) have been recaptured and four of these recaptures were from fish that had travelled a distance of over 800 km. Speckled snapper Copper shark Lutjanus rivulatus Carcharhinus brachyurus 740 tagged, 164 recaptured = recapture rate 6825 tagged, 257 recaptured = 3.77% recapture rate Longest distance travelled 63 km. Longest distance travelled 1790 km. Maximum days free 889 (2.4 years) Maximum days free 3981 (10.9 years) Bruce Mann and his team in the St Lucia Marine Reserve During the R&S Nationals held at Struisbaai in 1999 a 620 mm tagged a speckled snapper near Leven Point on 3 August PCL copper shark weighing 6 kg was tagged and released. Only 116 days later this same fish was re-caught at Lala Nek by This shark was recently recaptured at Stillbaai and during its Mike Tyldesley, some 63 km to the north. This was an incredible 2195 days at liberty (6 years) it had grown by 280 mm in length, recapture for a species that has so far proven to be extremely gained 10 kg in weight and had travelled 280 km. resident. Out of the 740 speckled snapper tagged, a remarkable 164 (22.16%) have been recaptured with an average distance moved being less than 0.2 km! INSTITUTIONAL SCIENTIFIC TAGGING FOR 2005 INSTITUTE AREA 2005 TOTAL RECAP % Marine & Coastal Management De Hoop Marine Reserve Oceanographic Research Institute St Lucia Marine Reserve SA Institute for Aquatic Biodiversity Tsitsikamma Marine Reserve Ezemvelo KwaZulu-Natal Wildlife Kosi Bay Estuary Reserve Natal Sharks Board KZN Coast

4 ANGLERS WHO HAVE TAGGED TWENTY OR MORE FISH DURING 2005 NAME OF ANGLER CODE FACET PROVINCE 2005 TOTAL RECAP % KYLE, EWAN JNR. KY4493 RS EST KZN KYLE, ROBERT JNR. KY4299 RS EST KZN HART, CLIFFORD HA2303 RS WC WALKER, SIMON WA0190 RS WC RAPSON, WESLEY RA0006 RS KZN LILFORD, CHARLES LI0449 RS EST WC POPE, GORDON PO0397 RS EC HAND, RUSSELL HA3863 RS DS KZN SPARG, BRADLEY SP0759 RS WC HUMAN, DAVE HU3768 RS KZN SCOTT, JONATHAN SC4354 RS WC CRABB, JOHN CR0005 RS WC BOTHA, ALAN BO3405 RS KZN CARY, ARTHUR CA4138 RS KZN LOUW, JEAN LO0001 RS WC SADLER, TONY SA2039 RS WC TYLDESLEY, MIKE TY3003 RS EST KZN MARSHBANK, GRANT MA0009 EST EC RUDMAN, WAYNE RU0005 EST EC RAWAT, ZAHIR RA0001 RS KZN FALLOWS, CHRIS FA2167 RS DS WC SCROOBY, LLEWELLYN SC3959 RS KZN DE WET, WYNN DE0277 RS EST WC HUMPHREYS, KEVIN HU0563 RS DS KZN SHEPPARD, JOHN SH4459 EST WC EGERSDORFER, TERENCE EG2711 RS KZN COETZEE, JOHAN CO0005 RS GAUTENG HUTCHINGS, KEN HU3086 RS WC LE ROUX, JOE LE3212 RS WC ROETZ, JOHANNES RO0650 RS KZN COATES, JOHN CO0006 EST WC JACOBS, GEORGE JA2558 DS EST KZN MANN, BRUCE MA0235 RS EST KZN VAN DER MERWE, DEON VA3530 RS EC CROUS, HENNIE CR0009 RS DS WC MARAIS, CHARL MA3556 RS WC SHAW, CAMBELL SH0006 RS KZN WHITE, MICHAEL WH0010 EST EC VAN NIEKERK, RUDY VA0006 RS WC POTTS, WARREN PO4339 RS EST EC BURTON, SIMON BU4441 RS EST EC JUDD, CHRIS JU4042 RS EST KZN PAUTZ, MIKE PA0122 RS WC VAN WYK, BERNARD VA2204 RS EST WC YOUNG, GRAEME YO3592 DS EC MACKENZIE, BERNARD MA4478 RS EC COX, KEVIN CO3296 RS DS KZN GROENEWALD, COENIE GR4498 RS WC ASHERWOOD, JEFF AS4499 RS KZN DE CLERCQ, CASPER DE0002 RS KZN SHEPHERD, BOB SH3996 RS EST EC VAN WULVEN, ALLEN VA0288 RS DS WC VAN JAARSVELDT, CHRIS VA3072 RS WC CATHERINE, QUINTON CA4482 RS DS WC PRINSLOO, WILLEM PR4099 RS KZN COMMERCIAL CHARTER GROUPS NAME GROUP AREA FACET 2005 TAGGED TOTAL TAGGINGS % RECAPT. Duarte A.M. Ratio Rani Africa, Indigo Bay Bazaruto Island, Mozambique DS BF Glanville Heydenrych Benguera Lodge Benguera Island, Mozambique DS Andrew Parsons Benguera Lodge Benguera Island, Mozambique DS FLY Antony Diplock Galeforce Charters Margaruque Island, Mozambique DS BF Guy Ferguson Ferguson Gamefish Charter Santa Carolina Island, Mozambique DS FLY Sean Amor Hooked On Africa Hout Bay, Western Cape DS Ben Pretorius Ufudu Flyfishing Kosi Bay, KwaZulu-Natal EST FLY Adrian Westraad Linene Island Resort Carbo Sao Sebastiao, Mozambique DS Tom Bradfield Lynski Deepsea Boat Charter Durban, KwaZulu-Natal DS BF Ryan Williamson Allure Gamefish Boat Charter Durban, KwaZulu-Natal DS BF Earl Strydom Linene Island Resort Carbo Sao Sebastiao, Mozambique DS FLY Kas v/d Merwe Black Watch Gamefish Charter Richards Bay, KwaZulu-Natal DS BF

5 MAIN FISH SPECIES TAGGED UP TO 31 DECEMBER 2005 Number Recaptured Km Travelled Days free Number Recaptured Km Travelled Days free Species Tagged Number % Mean Max. Mean Max. Species Tagged Number % Mean Max. Mean Max. galjoen snapper: river / rocksalmon shark: dusky hammerhead shark: scalloped kob: dusky kingfish: blacktip / yellowtail shark: copper/bronze whaler stingray: honeycomb gulleyshark: spotted geelbek / Cape salmon grunter: spotted shark: longnose blackfin / spinner garrick / leervis stonebream / stinker shad / elf houndshark: hardnose smooth steenbras: white/pignose kingfish: bigeye guitarfish / giant sandshark mackerel: queen / Natal snoek Roman marlin: black shark: spotted ragged-tooth shark: tiger sailfish shark: Zambezi / bull shark: broadnose sevengill catshark: shorttail carpenter / silverfish shark: sandbar butterfly ray / diamond ray yellowtail: Cape zebra / wildeperd seventyfour stingray: blue pompano: southern kingfish: giant marlin: striped musselcracker: black / poenskop hottentot musselcracker: white / brusher stumpnose: white bream: bronze stumpnose: red pompano: largespot grunter: javelin / mof baardman / bellman / tasselfish rockcod: Malabar albacore / longfin tuna houndshark: whitespotted smooth perch / riverbream marlin: blue hammerhead shark: smooth hottentot: blue stingray: sharpnose / brown skate: spearnose mackerel: king/couta kingfish: bluefin rockcod: catface eagle ray: spotted stumpnose: Natal / yellowfin bream grunter: cock stumpnose: Cape stingray: thorntail santer/soldier shark: Java shark: blacktip Scotsman catshark: striped/pyjama jobfish: green / kaakap rockcod: yellowbelly kingfish: longfin snapper: speckled stumpnose: bigeye duckbill ray Englishman shark: soupfin / vaalhaai kob: silver kingfish: brassy / greenspot Hammerhead shark: great tuna: yellowfin grunter: saddle dageraad kob: squaretail steenbras: red/copper

6 NATAL SHARKS BOARD TAGGING REPORT BY SABINE WINTNER, NATAL SHARKS BOARD Staff tagged a total of 70 sharks in 2005, 19 of which The 19 sharks that were injected with the chemical were also injected with tetracycline for ageing purposes. tetracycline are part of the TETRACYCLINE TAGGING The majority of these animals (50) were caught in the PROJECT, which was started in 1993 to assist with the nets (Table 1) and were comprised mainly of raggedtooth ageing of sharks. Sharks can be aged by counting and tiger sharks. growth rings in their backbone, very much like ageing a tree. When the shark is injected with the chemical Table 1: Number of sharks tagged and released from the tetracycline an artificial growth ring is created which nets. can be used as a time reference. Injected sharks are Total Total tagged with an orange spaghetti tag labelled SPECIES tagged injected "Tetracycline" and the tag number has the prefix "BT", in Blacktip 3 2 contrast to the normal yellow spaghetti tag with a "B" Copper 2 1 number. Please remember that the NSB depends on Dusky 8 1 anglers to make recaptured tetracyclined sharks Great white 1 1 available to the research department. The NSB is Java 1 0 offering a "reward" of R 100 to anglers who make the Mako 1 1 shark, or a 20 cm long piece of the backbone, AND the Raggedtooth 10 6 tag available. The NSB will collect the shark or the Sandbar 2 1 backbone and the tag from the angler. The backbone Spinner 3 1 should be wrapped in tinfoil or newspaper and stored Tiger 15 2 frozen and in darkness so that the chemical mark does Zambezi 4 2 not fade. TOTAL The tagging of rays and guitarfish caught in the nets Of the 70 tagged sharks, two were recaptured. A continued and 11 giant guitarfish, four spotted eagle rays raggedtooth shark caught in Richard Bay was and three duckbill rays were tagged. Two diamond rays, recaptured four and a half months later in Southbroom, one devil ray and two manta rays were also tagged. while a mako shark, tagged and injected in Thompson's There have been no recaptures of the over 140 tagged Bay, was recaptured a day later at Ballito. This shark rays (excluding giant guitarfish) since the start of the ray showed traces of the tetracycline in the flesh around the injection site. Apart from the above-mentioned recaptures, two animals tagged prior to 2005 were recaptured. A raggedtooth shark tagged in April 2004 at Leven Point was recaptured by an angler in January 2005 near Fish River Point having travelled over 860 km. The angler re- released it again. A catface rockcod, tagged by staff in March 2004 at Port Edward was recaptured eight months later at the same location and was also re- released. Twenty sharks were tagged after being captured by means other than the shark nets. A dusky shark was tagged when caught on the T.O. Strand experimental drum lines (this experiment was terminated after a few months). Nine smooth houndsharks and one scalloped hammerhead were tagged by staff during private fishing activities and an additional eight raggedtooth sharks were tagged underwater at Leven Point (Cape Vidal) by means of a modified speargun. One dusky shark, caught in a seine net during the sardine run was tagged and injected by NSB staff. Of the 20 tagged animals, only one was recaptured. This was a smooth houndshark, tagged in February at Port Edward and recaptured at the same location. tagging project in Additionally, two rockcods and one brassy kingfish were tagged by staff during private outings. BULLS, EAGLES AND DUCKBILLS - AN ATTEMPT TO AVOID COMMON NAME CONFUSION Unfortunately the fish books commonly available at book stores have perpetuated some confusion around the common names of some of the ray species caught and tagged by our anglers. This ambiguity makes it difficult for the Tagging Officer to know exactly what type of fish has been tagged. In order to overcome this problem we have decided to try and encourage you, as members of the Tagging Project, to use the following common names. Myliobatus aquila Eagleray Pteromylaeus bovinus Duckbill ray We suggest that you do not use the common name bull ray as this is used ubiquitously between the two species and is the source of much confusion. The only other similar species are the spotted eagleray Aetobatus narinari and the flapnose ray Rhinoptera javanica, both of which are very distinct and there is no confusion with their common names. 6

7 WHAT LENGTH SHOULD I MEASURE WHEN TAGGING A FISH? The different ways of measuring fish has caused some confusion among anglers and many are uncertain what the preferred measurement to be taken is. To help avoid this confusion we have prepared some clear guidelines. The different types of length measurement are clearly illustrated in the diagram below. The reason why we specify which type of length should be measured is because it is the most accurate length type for the species concerned. However, it is important to realize that all size limits given in the regulations use TL. So if you forget which length type to measure then use TL, but please be sure to indicate on your tagging card which length type you have measured. U Bony fish with a forked or lunate tail (e.g. kingfish, galjoen etc.) measure fork length (FL) U Bony fish with a rounded or square tail (e.g. kob, rockcod, etc.) measure total length (TL) U Stingrays - measure disk width (DW) or wingspan U Sharks - measure pre-caudal length (PCL) (i.e. to the notch just before the start of the tail) Remember to measure your fish holding the tape measure as straight as possible and not curved over the body of the fish. It is often easier to stretch the tape measure out on a flat surface and place the fish on to the tape to get a good measurement. For this reason scientists generally use measuring boards to try and get more accurate length measurements. However, remember that survival of the fish is paramount so don't faff around too long trying to get an exact measurement. Using centimetres (cm) as the measurement unit is fine and do not worry about going to millimetres (mm), especially if you are just using a tape measure. Unfortunately there are a few fish which do not fit neatly into the above categories which you need to be aware of namely: U Sandsharks measure total length (TL) U Catsharks and houndsharks measure total length (TL) THE MYSTERIOUS TAG RETURN - WAS IT A BIRD OR WAS IT A SHARK? During August 2005 we received a letter and a fish tag from a gentleman reporting that he had recovered a spaghetti type tag from a cormorant which he found lying dead on the beach at Brandfontein near Cape Agulhas a few months earlier. bird. This time the phone was answered by his wife who cast more confusion as she added that her husband's friend who was with them on the beach that day, had to actually break the bird's leg to remove the tag. By now I could sense that something did not quite add up and I was getting absolutely nowhere so decided to drop the case. Immediately my brain raced, what was a bird doing with a fish tag stuck in it? Again I read the letter to make sure that I had not miss-read it, yes it definitely was a bird! Going to the computer I called up the tag number to find out if that tag had indeed been reported used. Our records showed that the tag had been inserted into a small copper shark of 630 mm at Skuplers Bay earlier in the year, by one of our tagging members Arno Dames. By now I could not help feel a little confused, how did the shark loose its tag to a sea bird! I decided to phone both parties concerned to sort out the mystery. It must have been a few days later when a I received a phone call from a cheerful sounding man who claimed that he was the gentleman walking with his friend on the beach when the cormorant was found. I thought to myself now what next! He announced that his friend had made a terrible messup with the tagging report. The cormorant had carried a ring tag, which he had in fact removed and sent on to Safring at the University of Cape Town. The tag his friend had sent in to ORI, had in fact been given to them by a local commercial skiboat fisherman from Struis Bay, who had removed it from a small copper shark he had caught in the area during mid April. It turned out that the shark had only been free for about 57 days before it was recaptured again. First I phoned the gentleman beach walker who was most excited to tell me about the tagged cormorant, unfortunately he was unable to remember where the tag actually was on the bird but he confirmed that it had come from the animal. I then phoned Arno who was at first pleased to hear from me, until I explained the purpose of my call, his voice changed and I sensed a note of apprehension in it, surely the Tagging Officer was not doubting his word? I went on to explain that there had to be an explanation and that I would let him know when the problem was sorted out. Meanwhile Arno had not been idle, he had phoned several of his friends to hear what they had to say about this confusing report on how a bird could possibly get a tag stuck in it that had been inserted into a shark! One can only imagine all the way-out stories his friends came up with and all the good laughs they had! On replacing the phone, I again decided to question the gentleman who had kindly reported finding the tagged At last the mystery was solved! 7

8 TAGGING ASSISTS MANAGEMENT AT KOSI BAY BY SCOTTY KYLE, EZEMVELO KWAZULU-NATAL WILDLIFE For over twenty years fish have been tagged and caught annually by the different fishing methods, as well recaptured at Kosi Bay. Over this time more than 2700 as first estimates of the abundance of some species. fish have been tagged and over 300 have been Ongoing tagging (Figure 1) has tracked these recaptured. A lot of time, effort and money has thus been proportions over the years and recent intensive tagging ploughed into tagging fish at Kosi, but what has it told us has produced comparable figures for each legal fishing and has it really helped to improve management of the method. Illegal fishing has always been recognized as a system? serious concern at Kosi Bay but just how serious was simply not known. Kosi Bay is one of the prime estuarine angling venues in southern Africa but it is also home to the largest The results now coming in are giving clear indications of traditional trap fishery in the region. It is well known for its the levels of competition and off-take of the legal and giant kingfish, record-sized rock salmon (river snapper) illegal use. Since 1980 fish tagging returns have shown a and occasional good numbers of spotted grunter, but clear, almost progressive increase in the proportion of anglers keep reporting that these recreational fish are fish recovered at Kosi Bay (Figure 2). The indications are being caught and sold by local residents in large that the proportion of fish caught by man has more than numbers. The fish of Kosi Bay are thus under trebled in the last twenty years and the pressure progressively increasing pressure from recreational, continues to grow. This information, however, gives the artisanal and small-scale commercial fishers and all managers, Ezemvelo KZN Wildlife and the Greater St these people rely on the same fish populations to sustain Lucia Wetland Park Authority, important information on their activities. which to base future management decisions. In the past there has been conflict between trappers and recreational anglers and, more recently, between trappers and gillnetters. Each fisherman feels that others are catching more than their fair share and are thus negatively impacting their own catches and the breeding stock. In areas like the Kosi Bay lakes, due to the many species involved and the size and complexity of the area, it is not possible to accurately count all the fish. Fish tagging is the most appropriate tool available for researchers and managers to establish estimates of the fish populations and determine the relative harvest taken by each fishing activity. 25 PERCENT RECAPTURED The area is a Nature Reserve, a Ramsar Wetland of International Importance and is part of a World Heritage Site and its management is under close scrutiny. This is why tag and recapture of fish in the system is now of critical importance. There are a limited number of fish in the lakes and the managers are charged with distributing the fish resource fairly and equitably among all human users, as well as leaving enough for natural predation and mortality, while ensuring adequate breeding stocks are maintained YEAR 2005 Figure 2. Overall percentages of tagged fish recaptured in the Kosi Bay Lakes from 1983 to It has recently been decided to phase out all legal gillnetting in KZN estuarine systems, including Kosi Bay. Other subsistence and traditional fishing is to be regulated and subsistence rod and line fishing is to have size and bag limits similar to those of recreational anglers. All fishers have been co-operating with the tagging project in the last couple of years and, for the first time, estimates are now being obtained of the numbers, type and proportion of fish caught by the illegal fishers. Recent tag recovery information (Figure 3) now shows the extent of legal use as well as an indication of the extent of poaching. Goggle & spear Recreational 13% 7% Intensive fish tagging in the early 1980's established baseline proportions of the Kosi Bay fish populations Illegal netting 10% Subsistence rod & line 17% Trap 53% Figure 3. Initial results of tag recaptures at Kosi Bay for the 2005/6 season, showing the percent of recaptures taken by each fishing method. Figure 1. A nice kingfish recently tagged and released at Kosi Bay. Continued on page 9 8

9 Continued from page 8 Managers can now clearly see that recreational angling concentrate their limited capacity on the fishing methods has a relatively small impact, compared to that of fish with the greatest impacts. Without such measurements trapping, and so strict control of recreational anglers of relative catches and fish populations, decisions would alone cannot seriously reduce offtake levels. Trapping have to be based on more subjective and speculative needs much attention and in the last few years information. subsistence rod and line fishing has increased markedly to more than double the catch of recreational angling. Ezemvelo KZN Wildlife and the Greater St. Lucia Illegal netting is probably catching many more fish than Wetland Park Authority would like to thank recreational recreational anglers and people illegally using goggles anglers for their high level of co-operation with the fish with traditional spears are now also catching more fish tagging work at Kosi Bay. Please continue to tag suitable than recreational visitors. fish and send all recovery information to the usual ORI address. Your help is contributing to the wise This information from fish tagging enables the managers management of the fish we all enjoy catching and often to devise and implement suitable regulations and releasing! FISH FACTS BY BRUCE MANN Catface rockcod Ragged-tooth shark Epinephelus andersoni Carcharias taurus This popular species of rockcod is endemic to South Ragged-tooth sharks, affectionately known as raggies, Africa with its distribution extending from southern are a popular species with SCUBA divers and shore Mozambique to the Eastern Cape. Catface rockcod are anglers alike. This interesting species of shark has an known to be a fairly fast growing species capable of unusual method of reproduction called intra-uterine reaching a maximum age of 11 years. Their mode of cannibalism. Mature females produce only two pups reproduction is complex and still has scientists once every two years and the first egg (ovum) to hatch in somewhat baffled. Like most rockcod species (Family: each arm of the uterus is known to feed off other eggs Serranidae) they are hermaphroditic (containing both and its siblings in order to obtain its nutrition (i.e. there is male and female tissues in their gonads), but the no placental connection with the mother but young are expression of this hermaphroditism is not typical. Many born alive - known as aplacental viviparity). Another rockcod species tend to demonstrate protogynous unusual feature of this shark is that in order to maintain hermahroditism (female component of the gonad neutral buoyancy in the water it periodically rises to the matures first and then they change sex to male at a larger surface to gulp air, which is kept in the stomach size), but catface rockcod is unique in that in a substantial (remember that sharks, unlike some bony fish, do not proportion of the population, the male component of the have a swim bladder). To date, some 2997 raggies have gonad matures first, and these fish stay male for the rest been tagged in the ORI/WWF-SA Tagging Project and of their lives. Some fish do however function first as 247 (8.2%) have been recaptured. The maximum time at females and then change to become male, whereas liberty for a tagged raggy was an impressive 12.8 years some stay as female for their whole lives. So, unlike other during which time it only grew 26 cm. Off the South rockcod species, there is no shortage of males. To date African coast adult raggies show a biennial breeding 985 catface rockcod have been tagged in the ORI/WWF- migration, with mating taking place along the KwaZulu- SA Tagging Project and a large number 141 (14.3%) of Natal and Transkei coasts during the winter and pupping tagged fish have been re-caught. Most recaptures have taking place in the south-east Cape during summer. In been taken in relatively close proximity (< 5 km) to where some parts of the world, such as eastern Australia, they were originally tagged, suggesting high residency. raggies have been decimated by deliberate fishing and However, a few fish (including one fish that was at liberty spearfishing. In South Africa, however, recent research for 7.8 years) have shown greater movements of up to conducted by Dr. Matt Dicken (Rhodes University) using 143 km from where they were originally tagged. This data from the ORI/WWF-SA Tagging Project, suggests movement behaviour is very interesting and, in addition that the raggy population is still reasonably robust. to their faster growth rate and a fairly similar sex ratio of Raggies are undoubtedly very vulnerable to over-fishing males and females, probably explains why catface but their sound population status in South African waters rockcod are still more abundant than their cousins the may, in part, be attributed to their decommercialised yellowbelly rockcod, which are extremely resident, status and the efforts of shore anglers to refrain from relatively slow-growing and have a shortage of males. gaffing their fish and releasing them unharmed back to From diving experience, it is obvious that catface the water. rockcod are some of the first visitors to take up residence on new artificial reefs or other jetsam that has fallen overboard. This suggests that some searching movement behaviour is displayed by adults. Further anecdotal evidence from shore anglers suggests that adult catface rockcod sometimes congregate in large numbers on sandy areas away from reefs. This behaviour may be related to spawning activity but further research is needed into this phenomenon. 9

10 A NEW DEDICATED MONITORING AND TAGGING PROJECT IN THE GREATER ADDO ELEPHANT NATIONAL PARK BY PAUL COWLEY, SOUTH AFRICAN INSTITUTE FOR AQUATIC BIODIVERSITY Since 2000, the Addo Elephant National Park in the Eastern Cape Province has been expanding its boundaries. Ultimately this expansion process will create the Greater Addo Elephant National Park (GAENP), which will encompass about hectares and conserve five of South Africa's seven biomes. The GAENP will also include a hectare marine component, making it the world's first 'Big Seven' reserve (by including southern right whales and great white sharks). The marine area will include the already proclaimed Bird Island Marine Protected Area home of the world's largest breeding colony of gannets and the second largest breeding colony of African penguins. Besides the significance of these breeding bird colonies, the waters of Algoa Bay are home to many important fishery species. Efficient and effective management of the GAENP marine waters will reduce the threat of overexploitation and with the inclusion of sanctuary (no-take) areas will assist with the recovery of already collapsed fish stocks. The format of this fish monitoring and tagging project will resemble the existing monitoring projects at De Hoop, Tsitsikamma and St Lucia Marine Reserves. Research anglers will make regular trips (every second month) and fish for two full days with the aim of catching and tagging as many fish as possible. The research will be undertaken within a five kilometre designated zone on the eastern extreme of the Sundays River surf zone including the rocky headlands at Woody Cape. Besides having the necessary tackle and bait, each angler will be equipped with a GPS to record the exact position at which each fish is tagged and released. This project will make use of exactly the same type of tags (Hallprint type PDL-1 plastic tipped dart tags) that are used in the ORI/WWF-SA Tagging Project, but will be inscribed with a telephone number instead of a postal address. Each tag will also have a unique number from which every tagged individual will be identified (e.g. tag # W 0053 was inserted into a white musselcracker of 795 mm fork length at 13h20 on 25 Feb 2006 at a known GPS coordinate). The easy-to-remember telephone number is 082 TAG FISH ( ) and will provide researchers with the opportunity to talk to the angler who recaptures any tagged fish and obtain as much information as possible about the recaptured fish. Such information may include the exact location of capture (maybe even another GPS co-ordinate), type of habitat (i.e. sandy beach, rocky shore, estuary, etc.) or depth in the case of fish caught from a boat, the time day, bait used, sea and weather conditions, whether the fish was kept or released as well as something about the health or condition of the fish, including aspects of tag fouling or tagging wounds. Making use of a telephone number also makes the response time much shorter compared to using a postal address. A shorter response time will also increase our chances of recovering the otoliths from tagged fish that were injected with OTC (oxytetracycline) for age validation purposes. To date, three trips to the GAENP coastal zone have been undertaken and a total of 167 fish have been caught of which 120 were tagged. We have already had two recaptures. The first was a white musselcracker that moved a minimum of 19 km in the 20 days it was free. The second was a lesser sandshark that was recaptured 50 m from where it was tagged only 30 minutes earlier. The latter recapture is very encouraging and suggests that our handling and tagging methods have minimal effect on the behaviour of these fish. A nice dusky kob caught and tagged on the GAENP coastline. THE SOUTH AFRICAN SHORE ANGLING ASSOCIATION (SASAA) IS COMMENDED ON THEIR PLAN TO INTRODUCE BETTER FISH HANDLING TECHNIQUES IN THEIR COMPETITIONS. SASAA has recently discussed the option of introducing the use of barbless hooks in their competitions. This was based on trials undertaken by the KwaZulu-Natal Coastal Angling Union. This is undoubtedly one of the most effective ways of improving the chances of survival of released fish. There have been a number of published studies which have proved this and, as further evidence, most linefish caught for the aquarium industry are now caught using barbless hooks as survival rates are much better. A second important change being debated by SASAA is to remove the need to weigh each fish caught. Instead points will be allocated based purely on the type of fish caught, or on the length of the fish in the case of large specimens. This means that over 60% of the fish caught will not even have to be taken out of the water, which will greatly improve their chances of survival. A third issue which is being discussed is that of gaffing fish. Some clubs are already using scoring systems where more points are allocated for fish that are not gaffed, which again greatly increases the released fish's chance of surviving. These improvements to the structure of shore angling competitions are strongly encouraged as it will ultimately go a long way in reducing capture and handling mortality and ensuring better fishing for the future. 10

11 TAGGING RESULTS FROM THE BAZARUTO ARCHIPELAGO, MOZAMBIQUE Anglers who have requested permission to tag fish in recovered 36 days later in the Zinkwasi Beach shark nets Mozambique waters have been given strict instructions 1288 km away! Another exciting recapture was reported to focus their tagging efforts on specific fish species. from a sailfish tagged off Ponta Chilola, Bazaruto and These include: king mackerel (couta), queen mackerel was recaptured 493 days later off Sodwana Bay, 1060 (Natal snoek), giant kingfish, largemouth queenfish, km away from where it was first tagged. southern pompano, yellowfin tuna, billfish (all species) and some shark species (i.e. blacktip & Zambezi). Some These recaptures confirm the theory scientists have that very interesting recapture results have been obtained South Africa shares some of its linefish stocks with from some of these fish species that have been tagged Mozambique, and underlines the need for both nations off the Bazaruto Archipelago during the past seventeen to work together to study and manage these resources. years (see table). The results presented here were obtained mainly due to Some of the most exciting tagging results came from the a handful of dedicated ski-boat anglers and charter boat recapture of a number of king mackerel. It was found that skippers operating out of the archipelago and the out of 22 king mackerel recaptured, seven travelled ORI/WWF-SA Tagging Project would like to southwards over a thousand kilometres to be recaptured acknowledge them for their efforts: in KwaZulu-Natal. The fastest moving fish covered the Louis Erasmus Bazaruto Island ( ) distance from Bazaruto Island to Umdloti in 161 days Duarte M. Ratio Bazaruto Island (2001 on going) averaging 8.5 km per day! The average time free for Andrew Parsons Benguerua Island (1996 on going) these seven fish was less than a year. Glanville Heydenrych Benguerua Island (2004 on going) Guy Ferguson Santa Carolina Island (1999 on going) Stan Walters Margaruque Island ( ) To date out of the 712 giant kingfish tagged, 17 have Willie Rothman Margaruque Island ( ) been recaptured, with only one fish having moved over Antony Diplock Margaruque Island ( ) 100 km. This particular fish measuring 72 cm fork length, Lee Westraadt Linene Island (2005 on going) travelled from Ponto Muanha, Benguerua Island to Earl Strydom Linene Island ( ) Ponta Da Mingo in 23 days, covering a distance of 117 Km Travelled Days Free km. The other recaptures Species Tagged Recapt. % Mean Max Mean Max have all been in close Kingfish: giant proximity to where they were Mackerel: king / couta originally tagged suggesting Mackerel: queen / Natal snoek that this species may be Marlin: black locally resident. Marlin: blue One of the most surprising movements reported to us recently was from a blacktip shark measuring 160 cm PCL tagged off Bazaruto l i g h t h o u s e a n d w a s Sailfish Shark: blackfin reef Shark: blacktip Shark: longnose blackfin Shark: Zambezi Tuna: yellowfin BILLFISH TAGGED BETWEEN 1976 AND 2005 AREA SWORDFISH SAILFISH STRIPED BLACK BLUE WHITE SHORTBILL TOTAL UNITED ARAB EMIRATES Dubai INDIAN OCEAN ISLANDS Mauritius Seychelles Madagascar KENYA Malindi to Pemba MOZAMBIQUE Carbo Delgado to Beira Bazaruto to Pomeni Morrungulo to Pta. Do Ouro SOUTH AFRICA Kosi Bay to Sodwana Bay Cape Vidal to Mapelane Richards Bay Durban Park Rynie Cape Point WEST & NORTH AFRICA Bom-Bom Algiers Tanzania GRAND TOTAL

12 REGISTER OF BILLFISH TAGGED DURING 2005 BOAT NAME BOAT CAPTAIN NUMBER OF BILLFISH TAGGED Ahab Glanville Heydenrych 8 sailfish Allure Ryan Williamson 10 sailfish Anglers Taxi Graham Morgan 2 sailfish Aqua-Holic Deon van der Merwe 1 sailfish Aqualord Pierre Barnard 1 sailfish Black Magic Lappies Labuschagne 2 black, 2 blue marlin Black Watch Kas van Der Merwe 1 shortbill spearfish, 3 black marlin, 3 blue Brokie Brandon Brokensha 1 sailfish, 1 black marlin, 1 striped marlin Canta Libre Gerhard Breedt 2 sailfish Cool Running H. Olivier 1 sailfish, 1 black marlin, 1 blue marlin Deep Blue Arthur Stamatis 1 black marlin Denwa-One Denham Townsend 1 sailfish Dream Catcher Mike Ross 2 sailfish El Dorado Calvin Wright 1 sailfish, 1 black marlin Endeavour Neville Kalil 1 striped marlin Eye-Tie Roberto Fierro 3 sailfish Finally A.Meyer 1 black marlin Fish Hawk Claude Boardman 1 sailfish Fish Tails Ross Armstrong 1 sailfish Fish Therapy Andrew Parsons 12 sailfish, 2 black marlin Flasher Wayne Dobeyn 1 sailfish Galeforce Antony Diplock 13 sailfish, 1 black marlin Gill 'N Tonic Michael Roberts 1 shortbill spearfish Green Mamba Ken Leach 1 sailfish Hands On Russell Hand 1 black marlin Hlatikulu Andre Olivier 1 black marlin Holy Smoke Craig Waldron 1 sailfish Ibo, Rola & Vamizi Duarte M. Rato & Captains 130 sailfish, 3 black marlin Ivanhoe Dick Pratt 4 sailfish Lagosta Alberto 1 sailfish Lauriska Danie Visser 2 sailfish, 1 black marlin Lets Go Andre Delport 1 sailfish Linene 2 Adrian Westrandt 2 sailfish, 1 blue marlin Little Joey C.H.Rothmann 1 blue marlin Loretta Johnny Le Roux 1 sailfish, 1 black marlin Lulatoo Sean Brimacombe 1 sailfish Lynski Tom Bradfield 11 sailfish, 3 black marlin Makhalimpi John Chubb 1 sailfish, 1 black marlin Malachite David Royston 1 sailfish, 1 black marlin Manjana Steyn Jacobsohn 1 sailfish Megalodon Rhys Griffiths 1 striped marlin Mighty Mouse Tony Jelinski 2 sailfish Milly Trevor Milstead 1 sailfish Miss B Have Russell Hand 1 sailfish National Spirit Peter Shore 1 blue marlin Outrigger Gary Kimble 1 sailfish Paaltjies Manie & Leon Badenhorst 1 sailfish, 1 black marlin Parra David Kruger 2 sailfish Quirimba Duarte M. Rato 13 sailfish Running Reels Pieter Vorster 1 black marlin Saltwater Kevin Hodgson 1 sailfish, 1 black marlin Schalla's Schalk Lubbe 1 sailfish Sea Ducer Garth Mc Gee 2 black marlin Seabound R. Jones 1 sailfish Shaluza Peter Rutherford 1 sailfish, 1 black marlin Solandri Joe Niehans 1 sailfish Squmfemfe Andre Badenhorst 1 black marlin Sucadi Neil Tapson 1 sailfish Swamp Thing Guy Ferguson 2 sailfish Sweet Carolina Demetrios Stamatis 1 black marlin Toy Toy Richard Cooper 3 sailfish Umkhulu Braam Duvenlage 1 black marlin Wave Walker Neels Cornelius 1 blue marlin Woodie Anton Gets 1 sailfish Yeld Cat 2 Phillip Marx 1 blue marlin 12