Lake users putting waterways at risk
4 February 2014
Boaties who fail to clean their vessels and trailers between waterways are risking the spread of aquatic pest plants in Rotorua's cleanest lake.
Bay of Plenty Regional Council staff have found fragments of hornwort - one of New Zealand's worst aquatic pest plants - in the shallows at Rotomā and pest weeds attached to boat trailers at the lake.
The regional council's Rotorua land management manager, Greg Corbett, says numerous fragments of hornwort have been found within the weed cordon at Rotomā, in a beach area where many boats launch.
Rotomā is currently clear of hornwort and Egeria and we need to keep it that way. The weed cordon can only prevent so much - pest plants can very quickly become established from fragments detaching from boats, trailers or other equipment used in waterways.
Weed cordons, constructed from netting and marked with buoys and markers, are in place in several Rotorua lakes and are designed to catch plant fragments that detach from boats and trailers, minimising the risk of aquatic pest plant invasions.
Boaties can be prosecuted for transporting aquatic pest plants from one waterway to another.
They risk undoing all the hard work being put into keeping these weeds out or contained. They're a real problem in some lakes and the last thing we need is to have them spread to others through people's carelessness.
Aquatic pest plants, can develop into thick blankets, altering habitats for native species, smothering native aquatic plants, clogging intakes on jet boats, fouling propellers and preventing recreational activities such as fishing and waterskiing.
Weed fragments are often unwittingly transported between waterways on boats and other equipment and can also harbour the eggs of unwanted pest fish species.
To keep pest weeds at bay:
- Always check, clean and dry any gear that comes into contact with the water between every waterway, every time. That includes boats, kayaks, rafts, canoes, paddle boards, paddles, boat trailers, vehicles and fishing gear, fishing attire such as waders, life jackets, wetsuits and footwear - even pets and children's toys.
- Give gear a thorough check and clean inside and out with decontamination solution (5 percent any common dishwashing detergent/nappy cleaner or 2 percent household bleach). On boats pay special attention to the outboard motor, anchor rope and anchor recess, bilge pump, mats, carpet.