by Dave Abbott
Two beady eyes framed by a pair of menacing spiky claws stared back at me as I pushed my face closer into the weed….then the stroppy little creature marched forward to sort me out. Great, a cray with attitude! He seemed totally unbothered by the fact that I was a few thousand times bigger than him, a characteristic pretty typical of freshwater crayfish.
I was in the middle of a refreshingly different and âsalt-freeâ dive in Lake Okataina near Rotorua, a beautiful little lake surrounded by dense bush and home to hundreds of these spikey little critters, as well as large trout, various species of cockabullies and a profusion of emerald green weed forest.
As Kiwi divers we are lucky to have a huge and varied coastline to dive from, and while this is a great situation to be in, it also means that few New Zealand divers spend much time diving in freshwater and estuaries. This is a pity as there is some great diving to be had in our lakes and rivers – and the bonus is you donât need to wash your gear afterwards!
As well as the obvious advantage to lazy divers mentioned above, New Zealandâs lakes and rivers can offer cool (okay, sometimes cold!) clear water, beautiful emerald green weed forests unlike anything found in the sea, and some varied and interesting freshwater creatures to observe.
Some of the Rotorua lakes such as the already noted Okataina feature delicate freshwater weeds, twisted tea-stained logs and a fine sand bottom (great for showing up your buoyancy skills or lack thereof) prowled by spiky prehistoric looking crayfish, pugnacious cockabullies, and if you are lucky, the occasional trout.
Quiet tributaries and pools in smaller bush rivers and streams can offer beautifully-marked native kokopu and large moody eels lurking under overhanging banks and logs, while clear, faster flowing rivers like the Waikato or Tarawera are home to good numbers of trout, usually seen head into the current on the down-current side of large rocks at the head of pools and below rapids. Drift diving such rivers takes the excitement factor up a notch with roller coaster rides over and around boulders as you are propelled along by an invisible force at a pace that would make Ian Thorpe look like a hungover nudibranch!
Although freshwater life is in general less varied and abundant than life in the sea, gliding through this totally different environment and observing the âunfamiliarâ creatures it harbours makes for interesting and rewarding diving non the less; and as well as the typically calmer water conditions you encounter it is also refreshing to emerge from your dive into a âpicture postcard sceneâ of bushclad hills as opposed to a âpicture postcard sceneâ of a coastal beach for a change!
Freshwater diving considerations
There are some marked differences between fresh and salt water diving, and as such a few things to keep in mind when making the switch: typically when diving lakes you will need to work out your dive plan using altitude tables as obviously many are well above sea level; you will require a bit less weight on your belt than you would usually use in the sea, and should take into consideration the probability that the water will be a little colder (depending on time of year and depth) – in summer lakes often have strong thermoclines and it is easy to get cold on a longer or deeper dive.
If you are doing a river drift-dive use some common sense and think about general river safety; know what is downstream and check for any hazards beforehand, plan your exit point(s), evaluate the current strength and stay with your buddy throughout. Diving over Huka falls would certainly be a new experience and make you famous, however it could also be your last experience and make you infamous as the âplonker who kept going!â
Lastly river drifts around central north island are often in prime fishing streams, so if you encounter any trout fishermen show them some consideration – that means not dropping comments like âwish I had my speargun with meâ and instead offering to start your drift further downstream so as not to disturb their fishing. A quick compliment on what a lovely Landrover they are driving may also help diver-fisher relations.
Where to go?
Explore! The central north island lakes such as Taupo, Tarawera, Waikaromoana, and the various Rotorua lakes are all good dives as are the Kai iwi lakes in the north. No doubt many of the south island lakes would also offer good diving, if a little on the cold side! The Waikato river, Kaituna and Tarawera rivers offer nice drift dives in places, and there are numerous other rivers around New Zealand that would offer potentially good drifts, -the deciding criteria being whether they are clear and safe to dive. Of course freshwater springs such as the renowned Pupu Springs provide unrivalled visibility and a fantastic dive experience, but always make yourself familiar with any local access regulations and dive etiquette to ensure such special places remain accessible to divers.
Where rivers meet the sea
While not strictly âfreshwaterâ, the zones where fresh and salt water meet in river estuaries and mangroves are a fascinating place to dive and often teeming with life. From freshwater eels to flounder, mantis shrimps to stargazers, schools of juvenile parore and mullet, and shags hunting through the shallow water like out of control DPVs, it is all happening in this zone and well worth spending an hour or two with a tank or even a snorkel! Mangroves are only found from the Bay of Plenty north, however there are plenty of estuaries right around New Zealand with good diving potential, just donât expect to see your depth gauge get anywhere near 40m; 4m maybe!
Why give it a go?
âA change is as good as a holidayâ or something like that! Sure you arenât going to find a feed of crayfish, but then one of the beauties of diving is that it gives you the opportunity to explore so many different worlds on different parts of the planet -all with spectacularly diverse life forms and landscapes; why limit your diving experiences to one environment?
Freshwater/estuary diving is also a great âbad weather optionâ if you are a frustrated dive addict and it has been shitty and blowing hard on the coast, most fresh water locations are relatively sheltered and usually accessible straight from shore, no boat required. You also wonât have to worry about checking the tides!