Rudd

(Scardinius erythrophthalmus)

Progressive Control Pest

Rudd is a stocky, deep bodied fish, with an olive back, silvergreen sides, a white belly and red-gold fins. They can grow up to 25 centimetres long and weigh up to 500 grams. Females are mature by two years of age and can lay tens of thousands of eggs. They were introduced illegally into the North Island. They were first detected in the Tasman-Nelson region in 2000. An active campaign has been conducted against them, along with other pest fish, in the Tasman-Nelson region by the Department of Conservation.

Reasons for the Strategy

An example of a Rudd fish.

Rudd are mostly carnivorous, feeding on insects and other fish, and occasionally on aquatic plants. They compete with other species for food and damage native fish habitat. They are classified as a “noxious fish” under the Freshwater Fisheries Regulations 1982 outside the Auckland and Waikato region.

Rudd is assessed at “2” on the infestation curve. It has been recorded in a small number of ponds on privately-owned land in Tasman District. The low incidence of Rudd in the Tasman-Nelson region, extensive areas of suitable habitat, and the potential for it to cause significant adverse effects, mean the benefits of progressive control far outweigh the costs.

Objective

To reduce the density and distribution of Rudd in the Tasman-Nelson region during the term of the Strategy.

Alternative Measures

The alternative option of “do nothing” or relying on voluntary control will not achieve the objective of eradication, 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 Rudd

The occupier shall report any suspected sightings of Rudd and allow access to the Management Agency, the Department of Conservation or their agents, to destroy all adult and juvenile forms of Rudd in water bodies on land that they occupy. A breach of Strategy Rule 5.11.5 is an offence under Section 154(r) of the Biosecurity Act 1993.

Biosecurity Act Requirement

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