By: Dr Bruce Mann
The 85th iSimangaliso surf-zone fish monitoring and tagging field trip was conducted at Cape Vidal from 10-13 November 2020. Unbelievably this is the 20th year since this project started in November 2001! After missing the May and August trips this year due to the national lockdown, it was great to be back on the beach again! Weather conditions were somewhat challenging with rain and a fresh SW wind gusting up to 28 knots on Tuesday and Wednesday. Thursday was a near perfect day and then the NE cranked up on Friday gusting up to 25 knots. The swell ranged between 2.5 and 1.5 m and the water temperature was a pleasant 24ºC. The team included Jeff Asherwood, Roger Mann, Justin Kyle, Piet van der Merwe, Simon Chater, Mike Karon and team leaders Rob Kyle and me.
During the trip, we caught a total of 227 fish of which 159 were tagged, 56 were small fish or non-tagging species and 12 were recaptures. The recaptures consisted of nine speckled snapper, two cave bass and one catface rockcod. The fish with the longest time at liberty was a speckled snapper originally tagged by Kevin Humphreys at Leven Point (SA-39) in May 2011. During its 3466 days (9.5 years) at liberty this fish grew 215 mm, it stayed in the same vicinity and was recaptured no less than seven times! A second speckled snapper recapture was free for 2465 days (6.7 years), while a nice cave bass recapture was free for 1827 days (5 years). All these fish remained in the same area and we got excellent growth information from them. The fish with the greatest distance moved was a small speckle of 325 mm FL tagged by Simon at EA35 in November 2019 and recaptured at SA-40 by Piet this trip, a swim of 11.1 km northwards. Roger caught a small male sandy of 1370 mm TL that Rob tagged with an acoustic tag as part of an ongoing project investigating the movement patterns of this critically endangered species.
As usual Rob took the honours and I just managed to sneak ahead of Mike and Jeff in terms of the number of fish tagged and recaptured (but unfortunately not in terms of size or quality of fish landed)!
A total of 130 fish (57.3%) were caught in the two previously exploited areas (EA & EB) – now called catch and release (C&R) areas, while 97 fish (42.7%) were caught in the two no-take wilderness areas (SA & SB). In terms of catch rate, the CPUE was slightly higher in the C&R areas (0.78 fish/angler/hour) compared to the no-take wilderness areas (0.57 fish/angler/hour). This is the second year in a row where we have caught more fish in the C&R areas south of Leven Point. This is a positive sign as it indicates continued good recovery of fish populations south of Leven Point since the implementation of the beach driving ban in 2002. However, on the negative side, there were many signs of continued poaching taking place in the no-take wilderness area including fishing markers placed along the beach and cooking fires at the base of the dunes. Again, we implore the conservation authorities to make every effort to patrol this important area, especially at night on the low tide.
A total of 29 fish species were recorded on the trip with 20 species caught in the C&R area and 23 species caught in the no-take wilderness area. No new species were recorded, so the total species count for the project remains at 116 species to date. Species composition was dominated by speckled snapper (56), largespotted pompano (24), cave bass (19), grey grunter (16), potato bass (14) and yellowbelly rockcod (13) amongst others. The overall lack of small fish such as grey grunter was surprising, but we put it down to the so called “poison wind” i.e. the south-easterly wind that blows after the passing of a cold front and is well known by anglers along the northern KZN coast to put fish off the bite.
Some great fish were caught during the trip including a magnificent giant kingfish of 1100 mm FL (25.8 kg) caught by Jeff on a plug at Leven Point. Rob caught a beautiful river snapper of 895 mm FL (10 kg) and Mike got a big potato bass of 810 mm TL (7.2 kg). Other good fish included the sandy of 1370 mm TL (14.4 kg) caught by Roger, another nice kingy of 640 mm FL (5.2 kg) caught by Justin, two more big spuds of 770 mm TL (6.2 kg) and 760 mm TL (5.9 kg) caught by Mike and Justin respectively, a triple-decker speckle of 613 mm FL (5.2 kg) caught by Simon and a surprising grey chub of 580 mm FL (3.5 kg) caught by yours truly. Please check out our new Fish App (Marine Fish Guide for Southern Africa for both Android and iPhone) for easy access to information on linefish including a length/weight calculator.
I would like to thank SAAMBR, the iSimangaliso Wetland Park Authority and Ezemvelo KwaZulu-Natal Wildlife for providing funds and logistic support for this long-term monitoring project. Thanks to Sifiso Vumase from iSimangaliso and James Wood from Ezemvelo for sorting out our gate access. Thanks to Adcan Marine for our bait and to Rob and Jason for the fresh mozzies and mackerel. Finally, I would like to express my thanks to the whole team for your hard work and enthusiasm, fishing conditions were tough but you all persevered and caught some beautiful fish!