Fish & Game Eastern Region Officers have released 1690 stripy tiger trout and 200 rainbow trout into Lake Rotoma.
Fish & Game eastern regional officer Mark Sherburn says the organisation has “reinvigorated” a programme to rear and release the unique tigers and is now releasing a significant number into the lake each year.
Seeing the young tigers leaping about in the shallows of Lake Rotoma on a cold day is a striking sight, he says.
“We’ve upped the ante in response to angler requests. We’ve had success in the past with the programme, but this is more responding to the level of interest we’re seeing from anglers.
“A typical comment from anglers has been “Are you still doing them? Keep them going”.
Tiger trout can’t breed – they’re a sterile hybrid, a cross between a brown trough and a North American brook charr.
Their attraction to anglers lies in the challenge to “catch something different that is unique and special”.
Lake Rotoma is the only lake in the country to stock the tigers.
Mark says the fish don’t fight any harder than rainbows and their appeal is more in the challenge of catching a trout with distinctive stripy marking, which lends itself to being mounted as a trophy.
Traditionally, anglers take in fish over ten pounds to be mounted, but the tigers are so unique that anglers are happy to take in four or five pounders for mounting to a fish taxidermist, explains Mark.
Tigers can grow larger than rainbows, similar in size to brown trout.
When the tigers are young, they are more brook char-like, but as they grow bigger they tend to take their behaviour and appearance from the browns.
They live for a longer time period than rainbows and put on “good” weight when conditions suit.
“The rainbows are mid-water feeders and are like kids,” says Mark.
“They zoom round at a hundred miles an hour foraging for food and burning off lots of energy. By contrast, the browns sit on the bottom and mooch along really slowly, so they’re not using energy at the same rate.”
He’s appealing to anglers who fish Lake Rotoma to contact them with details of any tigers they catch.
The yearlings are about 15 centimetres in length when released and have been “fin marked” with the right pelvic adipose fin clipped for identification.
“If anglers catch tigers we’d really like to hear about it. Everything we do has to benefit anglers. In the past, when we’ve reduced tiger numbers, it’s because we weren’t getting much feedback, and thought anglers weren’t catching them.
“If we’re not hearing from anglers saying ‘That’s really good, that’s working, and we’re catching and enjoying them’ then we have to assume we’re not spending anglers’ money wisely.”
Mark says that aside from the novelty of being able to fish for tigers, Lake Rotoma has plenty of appeal as a beautiful lake with high water quality.
It’s one of the lakes with weed cordons around boat ramps designed to help prevent the spread of aquatic weeds and is seen as particularly vulnerable to invasion from some of the worst weeds.
“We remind anglers they need to heed the ‘check, clean, dry’ (CCD) message. Boaties need to be responsible for their own lakes, and for checking their boats and gear before they travel between different waterways.”