Perch

(Perca fluvitalis)

Progressive Control Pest

Perch are an attractive olive-green fish with prominent stripes, growing up to 60 cm in length and up to 2 kg in weight. A native of Europe, they were introduced in 1868 from Tasmanian stock that was originally imported from England and are well established in Otago and Wellington. They prefer still or slow-moving waterbodies containing good quality water. They are generally not recognised in New Zealand as quality sporting fish but are valued by European anglers and are part of a group described as coarse fish.

Reasons for the Strategy

Two olive green perch fish swimming in the river.

Perch are predators, feeding on insects, small fish and their larvae. They are considered to pose a significant threat to native aquatic fauna in the Tasman-Nelson region and to recreational trout fisheries. An active campaign has been conducted by the Department of Conservation in recent times against illegal releases of perch.

Sports fish are defined in the Conservation Act 1987 and the Freshwater Fisheries Regulations 1983. Schedule 1 of the Regulations lists perch as sports fish. However, Fish and Game NZ have responsibility for management of the sports fish resource for the recreational interests of anglers and the recent arrival of perch in the Tasman-Nelson region was not authorised by the Nelson-Marlborough Council. They have developed policies that may allow a limited population of perch to be established in an appropriate area as a sports fish.

They are assessed at “2” on the infestation curve. At present, they have a very limited distribution in the region, having been recorded in a number of small ponds. The low incidence, extensive areas of habitat, and the potential for it to cause significant adverse effects mean the benefits of progressive control far outweigh the cost.

Objective

To reduce the distribution and density of Perch in the Tasman- Nelson region during the term of the Strategy, except for any area that is legally sanctioned by the Director-General of Conservation and the Nelson-Marlborough Council of Fish and Game NZ and granted an exemption by the Management Agency.

Alternative measures

The alternative of doing nothing or relying on voluntary control will not achieve the objective of reducing the distribution and density of Perch and will result in significant additional costs to the community with respect to lost natural values and the increased cost of control in the future.

Strategy rule for Perch

The occupier shall report any suspected sightings of Perch and allow access to the Management Agency, the Department of Conservation or their agents, to destroy all adult and juvenile forms of Perch in waterbodies on land that they occupy, except for legally sanctioned areas.

A breach of Strategy Rule 5.x.5 is an offence under Section 5.4.5 of the Biosecurity Act 1993.

Biosecurity Act requirements

No person shall knowingly sell, propagate, breed, release or commercially display Perch under Sections 52 and 53 of the Act.

Note: The unauthorised release of Perch without the approval of the Director-General of Conservation and Fish and Game NZ is also an offence under the Conservation Act.