Goukamma Marine Protected Area Catch, Tag & Release Fishing Project Report

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1 Goukamma Marine Protected Area Catch, Tag & Release Fishing Project Report April 2016 Compiled by: Wayne Meyer & Alex Munro

2 Introduction Goukamma Marine Protected Area (MPA) initiated the catch-per-unit-effort (CPUE) catch, tag & release fishing project in October This was done in an effort to monitor the in-shore linefish species diversity and abundance. The question is whether CPUE is increasing or decreasing over time. Data is collected at Oysterbeds within Goukamma MPA and at the adjacent study site, roughly 15km west of Goukamma next to Gericke s Point, outside of the MPA, in the geologically and oceanographically similar habitat of Gona s. Besides species diversity and abundance the finer inshore movements of fish are monitored and all data contribute towards the Oceanographic Research Institute s national tagging programme. Materials & Methods Volunteer anglers from the local community are used to conduct the sampling within the two 2 km sites. Eight weekend outings are conducted per year. Bias is reduced by strict rules such as designated bait & tackle, rules to time spent within 100m bins and randomised weather conditions. Effort is equally spread across and within the two study sites. Efficient and correct handling and tagging of the fish is maintained to ensure minimum losses and trauma to the fish. Results From the launch of the project in 2013, 18 outings were conducted till the end of This boils down to 35 days of fishing, since one day was cancelled due to unforeseen circumstances. Fifty-five anglers have fished in the project. At Oysterbeds 438 fish have been caught, with 180 of them being tagged. Twenty six species have been recorded (Table 1). At Gona s 303 fish have been caught with 93 of them being tagged. Twenty-seven species have been recorded (Table 1). Table 2 shows the amount of each species caught at Oysterbeds, whereas Table 3 shows the amount of each species caught at Gona s.

3 SPECIES OYSTERBEDS GONA'S COMMON NAME CAUGHT TAGGED CAUGHT TAGGED Banded Galjoen Belman Blacktail Bronze Bream Bronze Whaler Bull Ray Cape Stumpnose Dark Shyshark Diamond Ray Duckbill Ray Dusky Kob Evileyed Pufferfish Galjoen Jan Bruin Leopard Catshark Lesser Guitarfish Pinky Puffadder Shyshark Raggedtooth Shark Red Fingers Sand Steenbras Santer Shad Smooth Houndshark Spiny Dogfish Spotted Grunter Spotted Gullyshark Streepie Striped Catshark White Musselcracker White Seacatfish White Steenbras Yellowbelly Rockcod Zebra TOTAL Table 1: A comparison of fish species caught at Oysterbeds vs Gona s (Meyer 2016). Twenty-seven different species were caught in both areas, although the species make-up is different.

4 Table 2: The amount of each species caught at Oysterbeds (Meyer 2016).

5 Table 3: The amount of each species caught at Gona s (Meyer 2016).

6 Table 4 shows the effort of each angler in how many two day outings were fished, how many fish were caught in total, how many fish were tagged in total, and an average fish tagged per outing. ANGLER FISH CAUGHT FISH TAGGED OUTINGS AVERAGE FISH TAGGED PER OUTING Achley Nortje Alex Munro Andre Piguet Andrew Wood Anthony Louw Anwar Arendse Armien Davids Ashraf Isaacs Brett Harris Calvin Fish Carlo Erasmus Carlo van Tonder Clement Arendse Cuan Payne Dale Holder Danie Lodewyk Daniel du Plesis Deon Naude Devan Lagendyk Dirk Pretoruis Dirk Smit Duane Roberts Gabriel Slabbert George Basson Gert Du Plessis Igshaan Essop Jaco Barendse Japie Hendriks Jean du Plessis Keith Spencer Ludwig Schnetler Mario Esterhuizen Marius Groenewald Marizelle Esterhuizen Mark Norval Mel Frost Mike Louw Morne Harris Piet Fanelo Raldo Potgieter Reggie Thomas Riaan Barnado Richard Muller Robert Dampier Roland Scholtz Ruben Gouws Ryan De Lange Shafiek Toffar Shaun van Zyl Shawn Mey Shuroo Abrahams Stefan Oosthuizen Stuart Atkinson Stuart Hunter Wynand Loftus Table 4: The amount of fish caught, tagged, and average tagged per outing per angler (Meyer 2016).

7 Table 5 shows the top eighteen anglers, who tagged an average of more than 2.8 fish per outing. Table 5: Top anglers average fish tagged per outing (Meyer 2016).

8 Table 6 shows the average and maximum lengths of fish caught at each area, as well as the angler who holds the record for the longest fish caught at each area. AMOUNT AVERAGE MAXIMUM AMOUNT AVERAGE MAXIMUM CAUGHT AT LENGTH AT LENGTH AT CAUGHT AT LENGTH LENGTH AT SPECIES OYSTERBEDS OYSTERBEDS OYSTERBEDS CAUGHT BY GONAS AT GONAS GONAS CAUGHT BY Banded Galjoen 5 286,8 301 Alex Munro Dale Holder Belman Achley Nortje/ 420 Carlo van Tonder Keith Spencer Blacktail Dirk Pretoruis Dirk Pretoruis Bronze Bream Keith Spencer 0 Bronze Whaler Anthony Louw 0 Bull Ray Stefan Oosthuizen 0 Cape Stumpnose 7 254,9 342 Andrew Wood Richard Muller Dark Shyshark Alex Munro Diamond Ray Stefan Oosthuizen Duckbill Ray Riaan Barnado Jean du Plessis Dusky Kob Danie Lodewyk Carlo van Tonder Evileyed Pufferfish ,9 204 Carlo van Tonder 3 173,3 187 Dale Holder Galjoen Riaan Barnado Mark Norval Jan Bruin Carlo van Tonder Keith Spencer Leopard Catshark Marius Groenewald 0 Lesser Guitarfish Cuan Payne Keith Spencer Pinky Anthony Louw Puffadder Shyshark Dirk Pretoruis Ruben Gouws Raggedtooth Shark 0 0 Red Fingers Alex Munro Sand Steenbras Stefan Oosthuizen Dirk Smit Santer Richard Muller 0 Shad Brett Harris Anthony Louw Smooth Houndshark Stefan Oosthuizen Achley Nortje Spiny Dogfish Brett Harris 0 Spotted Grunter Stefan Oosthuizen Richard Muller Spotted Gullyshark Cuan Payne Stefan Oosthuizen Streepie Dale Holder Striped Catshark George Basson Richard Muller White Musselcracker Cuan Payne Keith Spencer White Seacatfish Clement Arendse Mel Frost White Steenbras Stefan Oosthuizen Cuan Payne Yellowbelly Rockcod ,5 425 Keith Spencer Zebra Ryan De Lange Cuan Payne Table 6: Average & maximum fish lengths, as well as record holding anglers, per area (Meyer 2016).

9 Table 7 shows the amount of record length catches caught per angler. Table 7: Number of record fish caught per angler (Meyer 2016). Discussion Since the data is insufficient to analyse statistically, we will discuss trends in the data, which give an indication of the findings to date. In equal effort 438 fish were caught in the MPA at Oysterbeds and 303 at Gona s. This is nearly one and a half times as many fish caught at Oysterbeds indicating that fish are more abundant at Oysterbeds in the MPA. Tagged fish at Oysterbeds were 180, which is nearly double that of the 93 caught at Gona s, indicating that there are more priority species over 300 mm total length (250 mm for Galjoen) at Oysterbeds. The most common species caught in descending order are Galjoen (141 at Oysterbeds and 48 at Gonas), Blacktail (116 at both Oysterbeds and Gonas), Lesser Guitarfish (56 at Oysterbeds and 52 at Gonas), Zebra (5 at both Oysterbeds and18 at Gonas) and Dusky Kob (19 at Oysterbeds and 3 at Gonas). The amount of priority species Galjoen and Dusky Kob are far more abundant within the MPA, although Zebra are more common at Gona s. There is a core team of anglers who have fished on many outings with Keith Spencer having fished 11 outings, Alex Munro 9 outings, Carlo van Tonder 8 outings, George Basson 7 outings and Antony Louw 6 outings. There are thirty two individuals who have only fished one outing.

10 The highest average amount of fish tagged per outing is led by Ludwig Schnetler with an average of 10, followed by Danie Lodewyk with 8, Gabriel Slabbert with 7 and Andrew Wood with 5.3. This must, however, be looked at in the broader picture which is that there are outings with good catches, and outings with bad catches, due to weather and sea conditions. Individuals which were lucky to only be present on outings with good catches have higher averages than those who landed up fishing in less than ideal conditions. Congratulations are due to the anglers who steadfastly stuck out through the poor angling conditions, well done Average and maximum lengths of fish caught at both areas shows that on average longer fish of most species are caught at Gona s, with the longest individual species lengths of most species also caught at Gona s. However, data is insufficient with many species only having been caught once. Stephan Oosthuizen holds the greatest amount of record length fish caught with 7 (in 4 outings), followed by Keith Spencer s 6 (in 11 outings), Cuan Payne s 5 (in 4 outings) & Richard Muller and Carlo van Tonder s 4 (in 5 & 8 outings respectively). Once again, data is insufficient with many species only having been caught once, leading to many unchallenged records (only one caught)! Conclusions & Recommendations More fish were caught and tagged at Oysterbeds than Gona s, although average and maximum lengths of fish were mostly greater at Gona s. This could be an indication that fish populations are greater within the MPA although more smaller individuals are present. Could the MPA be a safehaven for smaller individuals? More food available in a closed to bait collecting area? The fact that less fish are tagged at Gona s is an indication that there are less priority species. This could be an indication of a greater extractive fishing pressure at Gona s, which is not often policed. The vast number of Galjoen caught at Oysterbeds, nearly three times as many caught at Gona s, backs up the theory of Oysterbeds being prime habitat for Galjoen, further indicating that Galjoen are experiencing favourable conditions within the MPA. The same can be applied to Dusky Kob where six times as many are caught at Oysterbeds than Gona s. Zebra, however, contradict this by being three times as many at Gona s than at Oysterbeds. Since 32 individual anglers only fished one outing, it is recommended to try get more regulars and less one-hit-wonders. Many a good angler has not returned to the project after unluckily landing in a bad fishing weekend on their first outing. Those who kicked off their fishing for the project on a good weekend have mostly returned. The fact that on some outings fishing is good, and other outings fishing is bad, must also be taken into account when looking at the data. An outing of bad fishing, although boring, is also a result, and an indication of the poor state of our inshore fish stocks. Since the data is insufficient to analyse statistically, it is recommended that this project continues for a minimum of another three years, in order to get scientifically robust data.