One of the least targeted fish in NZ waters is the mighty bull-nosed catfish. Its lack of appeal is very easy to understand with its poor eating quality, modest size and fighting characteristics that would bore even the least ambitious coarse fisherman. For the sixty odd spearos who converge on Lake Taupo’s southern bays every year though the ugly little critters provide the perfect excuse to catch up, have a dive and a beer and slay a whole pile of them at the annual Catfish Cull.
The bull-nosed catfish, Ameiurus nebulosus,
were first introduced into New Zealand fresh waterways from the United States in the 1870’s. The first release was in Auckland’s St John’s Lake and since that initial liberation they’ve spread throughout the lakes and streams of the North Island and become abundant in the Waikato River catchment. They were first noticed in Lake Taupo in the early 80’s and have become a significant pest both to our native fishes and invertebrates and other introduced gamefish. Quite why anyone would want to go to the considerable effort of importing and releasing such a worthless fish is beyond me. Apparently they’re often released into Aussie dams as a food source for other fish like murray cod so maybe something like that was the original plan. Who knows?
The annual Cull has become one of the highlights of the spearfishing calendar with divers traveling from all over the country to participate. The event is the brain child of Pat Swanson and came about during the lead up to the 2009 Spearfishing National Champs held out of Tauranga. Gale force winds and huge seas were keeping everyone out of the water in the days before the competition and a bit of lateral thinking was needed to get any training in. Bored divers were driving the 3 hours to Taupo to train in the lake and practicing on the only fish on offer – the catfish. It turns out there are masses of them and they were great fun if not particularly challenging to hunt. Being a competitive bunch it wasn’t too long before it became a contest and a new tournament was born.
January 2010 saw the inaugural Lake Taupo Catfish Cull. Approval was sought from DoC, Fish and Game and local Iwi and was given (probably out of good humour more than anything else). The main concern from all parties I guess was that there were going to be a bunch of rubber clad maniacs all through the Lake murdering their precious trout. One of the first ideas to try and allay these fears was to make the competition handspear (Hawaiian sling) only – trout are quite flighty and vary rarely allow a diver within speargun range let alone the foot or so that a handspear can shoot. This wouldn’t be much of a handicap against the much dumber catfish though. Sponsorship from Wild Blue made very cheap spears available on the day and the result was the most accessible event on the spearfishing calendar. The novelty of the competition along with the easy, fresh water conditions and the lack of serious competition pressure meant that many guys dived with their kids or partners and there was a real carnival atmosphere.
That’s not to say that everyone was taking it easy. Some of the best divers in the country were there eager to prove themselves in the unusual environment and format. No one had done more than a day or two of catfishing before so almost nothing was known of their preferred habitat, what their habits were and how they would behave when confronted by a diver. Nor was much known of the area. We were limited to the southern end of the Lake with Motuoapa as the base but where should we go from there? Would using a boat be helpful or a hindrance? My partner, John Anderson, and I spent a lot of time on the net trying to find answers to these questions. There were DoC research papers that gave hints as to the best areas to focus on and there was plenty of info from overseas about what sort of bottom terrain etc they preferred. There’s no substitute for actual time in the water scouting so the day before the comp we were down in Taupo checking out the hot spots we’d identified and testing some of our new theories. The main thing we learnt was that the cats loved burley. And what better burley to use on catfish than catfood! Our strategy for comp day was going to be setting up several burley stations out around a marker and spending the 6 hours of competition working our way around them. No one really had any idea how many fish were going to be speared and the competition was going to be for the bulk weight of forty catfish ie each pair could weigh in forty fish and the team with the heaviest forty wins.
Our burley strategy was working; we had six stations going and there’d be at least one new fish on each one after we’d speared the last. Our stations were set at about 7-8m of depth. The fish weren’t particularly flighty but we’d occasionally spook them or miss with the hand spears and have to move off to the next station. At the end of the day we had sixty something catfish and were convinced that we’d win. We didn’t. We weren’t even really close. There were eight other teams with over forty catfish and ours were the lightest of them. One team had shot 97 catfish. It seems that the burley trick while effective wasn’t anywhere near as important as finding pockets of large catfish. The limit of forty fish was also a joke. The idea of the comp was to get as many of the pests out of the Lake as possible so our format would have to be changed to reflect that – either just bulk weight or bulk numbers.
This year was the third year the comp was held and the amazing numbers of fish speared reflects the increased knowledge of the fishery and the fine tuning of strategies. This year the top four pairs shot over 100 fish and there was a total of over 1000 fish taken out of the Lake. The overall winners Reid Quinlan (who has won all three competitions) and Long John Anderson weighed in a staggering 150 fish with a total weight of 44 kilos. To land that number of fish means shooting more than two per minute of the competition. Obviously using a handspear is the only way this would be possible as you’d struggle to reload a speargun twice a minute let alone dive and shoot a fish as well.
So what about next year? 150 seems an inconceivable number of fish but the winners all reckon they were only shooting one out of every seven or eight catfish seen. So how do you physically shoot more? Perhaps diving with more than one spear is the answer to be able to shoot more fish per dive. What seems certain though is that the average number of fish speared is sharply increasing each year as more is learnt about them. It’s hard to imagine that sixty divers having a shoot up once a year can have any real impact on the fish numbers but I guess every bit counts.