Information is available for identifying species, the best methods of control and management of these pests, biocontrols and how the responsibilities for managing these pests are shared.
There are many plants and animals in the Tasman region that are considered undesirable. Ways of managing these are outlined in the Tasman-Nelson Regional Pest Management Plan.
The Tasman-Nelson Regional Pest Management Plan provides a framework for efficient and effective pest management in the Tasman-Nelson region by:
Further information about the plan can be found at the link below:
There is also a summary booklet that highlights your responsibilities for dealing with pests at your place. Use the link below to check it out.
There is a free online tool available to assist farmers and agricultural professionals with pest and weed identification and management decision making.
Find out more about the pests and weeds that affect the Tasman region:
Pest animals is a category that includes introduced animals, birds, fish and insects.
Most introduced birds are widespread and have become well established. However, there is concern about the impact on horticultural crops posed by birds such as rooks that have not yet become established. For this reason, they have been included in the Tasman-Nelson Regional Pest Management Plan and rural landowners undertake an active surveillance campaign to spot any rooks.
At this stage, there are no known rookeries in the district. Further information on rooks and magpies can be found in the Regional Pest Management Plan.
Animals that are considered a pest to many rural landowners (e.g. pigs, deer) because of the damage they do to native vegetation may be a valuable resource to hunters. Others that may pose a risk to cattle by transmitting Bovine Tb (e.g. possums) can also provide some economic benefits to trappers in accessible areas. Most rural landowners consider animals such as goats, ferrets, stoats and weasels as pests and may trap them to protect native vegetation and native birds.
In Tasman District, possums, feral cats, feral rabbits, hares, ferrets, stoats and weasels have been included in the Regional Pest Management Plan (RPMP) as Containment pests, where control by landowners is needed to reduce their numbers and slow their spread to adjoining properties and to other parts of the region.
A declaration on 1 July 2017 established a programme to manage and eradicate the Mediterranean Fanworm - Sabella - in the Tasman District. Parallel declarations have also beeen made in the Marlborough District and Nelson City areas.
The purpose of the programme is to eradicate Sabella or to reduce its spread. The programme seeks to achieve that through:
Because Sabella is not named as a pest in the Regional Pest Management Plan, the Council has to use Small Scale Management Plan powers under the Biosecurity Act.
Declaration of a small Scale Management plan allows Council to use those powers to ensure vessels and structures are maintained clear of Sabella.
Sabella is an introduced, tube-dwelling fanworm that attaches itself to natural and artificial surfaces (eg, rocks, vessels and structures) in subtidal marine environments. Since 2008 it has become well established in many parts of the country (Whangarei, Waitemata, Lyttelton and Tauranga Harbours and on the Coromandel Peninsula).
Surveillance in the Top of the South area from 2013 onwards has found small number of Sabella on commercial and recreational vessels and marine structures. It is poised to spread to marine farms and into natural ecosystems. Co-ordinated and timely responses are required to slow and contain the spread. The Mediterranean fanworm is a marine animal that is infests coastal waters and is typically found in harbours and estuaries, living in depths of anywhere between one to 30 metres.
It consists of a segmented worm living inside a tube which is usually fixed to a hard surface. The worm has a single spiral fan (radiole) which extends out of the top of the tube. The tube is tough and flexible and often muddy in appearance. It can often have other organisms growing on the surface.
Sabella can grow to 600mm in length and establish in densities up to 1000 per square metre effectively smothering other marine organisms and competing for food.
Sabella is easily transported to new locations on dirty boat hulls and inside vessels pipework particularly underwater intakes and discharges.
The first Sabella detection was made at Port Tarakohe in September 2016.
In all, 12 adult fanworms were removed from the port structures and around the marina, funded by Tasman District Council (cost $6,000).
As at January 2017, planning was underway to determine the levels of future surveillance needed for this area (covered in SSMP Operational Plan).
During June 2017 a full survey and clearance of Sabella from Port Tarakohe was undertaken removing a further 25 Sabella.
Repeat surveys for and clearance of Port Tarakohe for Sabella are programmed over the next 3 years with the intention of removing any Sabella which may re-establish.
Sabella is also present in very low numbers in Nelson Harbour and in the Picton / Waikawa Bay areas. All three Councils are working together on the management programme.
German wasps arrived in NZ about 60 years ago and common wasps arrived about 20 years ago. They have had a dramatic effect on a range of native birds and insects, competing for nectar with birds such as tuis and bellbirds, and killing large numbers of native insects.
Some people react strongly to wasp stings and multiple stings can lead to serious harm or death.
If you have any concerns about wasp nests, please Contact the Biosecurity Team.
Here are some useful guidelines available for helping to avoid wasp stings.
Weeds are pest plants (usually introduced) that compete with productive plants (eg clover, grass, horticultural crops) or with indigenous plants. They compete by slowing their growth, shading them out or preventing regeneration of seedlings. Weeds can be controlled by physical removal (grubbing or cutting) or by herbicides (applied internally or externally).
In Tasman, gorse and broom are widespread, having been introduced and spread by early landowners and by animals and birds. The widespread use of fire to control pasture that was reverting to bracken and woody vegetation eliminated much of the competition for these weeds. The long-term viability of gorse and broom seed (more than 20 years in the ground) make it an extremely difficult plant to eradicate.
Some weeds pose a much greater threat than others. Responsibility for controlling weeds that pose the greatest threat lies with Biosecurity NZ, a department of the Ministry of Agrciulture and Forestry. Weeds that post a significant threat to economic or ecological values are usually included in regional pest management plans.
The Tasman-Nelson Regional Pest Management Plan lists 37 species of weeds under four different categories. These are weeds where the Council is satisfied that the costs of controlling them is justified by the benefits that this will bring. High-risk weeds with a very limited distribution are usually targeted for eradication. Weeds with a wider distribution may be progressively controlled to reduce their density and/or distribution. Widely-distributed weeds may be subject to boundary control to protect landowers with clean properties from being re-invaded from neighbouring properties.
The following website pages have more information which you may find useful:
Introduced fish such as trout and salmon provide recreational benefits to many anglers and are the basis of many a fine meal. There are other introduced freshwater fish such as koi carp, perch, rudd, and tench that could provide some sporting benefit to fisherman, but this would be outweighed by their impact on waterbodies.
Within Tasman District, the Department of Conservation have undertaken an active campaign against them and other fish such as Gambusia. For this reason, they have been included in the Regional Pest Management Plan. Further information on pest fish is contained in the Regional Pest Management Plan.
This section describes aquatic and wetland invaders as identified in the Tasman-Nelson Regional Pest Management Plan.
Please note that most aquatic and wetland plants are dispersed by stem or root fragments, so care should be taken when removing such plants to remove all material. Consider carefully what plants you buy for ponds and aquariums. If unsure, check with a Biosecurity Officer. Never dump aquarium contents or water into stormwater drains or water ways.
Identify pest ground covers and grass invaders which are included in the Tasman-Nelson Regional Pest Management Plan.
The brochure containing this information is available below:
Identify pest tree invaders, some of which are included in the Tasman-Nelson Regional Pest Management Plan.
The brochure containing this information is available below:
Taiwan cherry (Prunus campanulata) is a deciduous species of cherry tree native to Taiwan. It is a small-sized tree, up to 10 m high, with alternate, thin green leaves that are 5-17 cm long, with sharply-toothed margins.
Taiwan cherry is a relative newcomer to the Tasman-Nelson region, with the first trees being brought here during the mid-1960s. It has since been widely grown as an amenity tree and its popularity has increased markedly over the past 20 years. From late July through to early September, mature trees produce thousands of appealing dark pink flowers that attract pollinators such as bees and tui. On the outset, this makes it a desirable ornamental specimen tree for people to plant.
Because Taiwan cherry produces flowers in late winter/early spring, flower fertilisation by pollinators is particularly high. These fertilised flowers produce small, astringent, fleshy cherries with a stony centre, about 10-12 mm in diameter. These fruit are eagerly sought by birds such as wax eyes, starlings, blackbirds and native pigeons, who spread them to other areas, such as regenerating native scrublands, in their droppings. Other animals, such as possums and pigs may also spread the seed in the same manner. The seeds have a particularly high germination rate.
Unlike other cherry trees, a Taiwan cherry tree has the ability to germinate in low light where it produces a very shade tolerant seedling.
With its characteristic single leader growth form, it is able to push up through over-head cover, eventually producing a cone-shaped configuration.
Unlike all other woody weeds in the Nelson area, except perhaps Douglas fir, Taiwan cherry is able to invade not only exotic scrub mixtures, but also native scrublands, where it can over-top native mahoe trees that may also be emerging through this scrub.
In Dodson Valley in north Nelson, Taiwan cherry has spread at a rapidly alarming rate to the surrounding hillsides, where it is dominating the native vegetation. The scrubland forest floor of these hillsides contained thousands of seedlings, which in recent years have been brought under control by contractors at considerable expense. This infestation resulted from one single specimen tree in a back yard property adjacent to the hill country land.
Unless Taiwan cherry is controlled now it will be extremely difficult to eradicate. There would eventually be swathes of pink throughout the foothills and forests of Tasman and Nelson.
Taiwan cherry seedlings are deep rooted and after just one year cannot be hand-pulled. Seedlings can be sprayed with glyphosate (Roundup) when in full leaf. Larger trees can be cut off at ground level, although the stump must be treated with a glyphosate gel to kill the root system. If this is not done, coppicing from the base will occur (forming a new tree). Trees can also be killed by drilling holes in the trunk and filling them with full strength glyphosate.
In other regions of the country, particularly the North Island, Taiwan cherry has become widespread and has been banned from sale, propagation and distribution by several local authorities. In areas such as Northland, Taiwan cherry now dominates many scrubland areas, and is considered too difficult to eradicate. Considering that the first naturalised (wilding) record for all of NZ was only in 1988, the rate of spread has been extraordinary.
Taiwan cherry does not cause issues in its native country, Taiwan, as it is kept “in check” by a range of native pathogens and insect vectors that predate upon it.
Opportunities to introduce some of these pathogens / insect vectors as biocontrol agents are probably very limited in NZ, given that plums, cherries, peaches, nectarines, apricots, and almonds are in the same genus (Prunus family). The potential risk to these other fruit and nut bearing trees by intentionally introduced Taiwan cherry biocontrol agents (if it was to be considered) would need to be carefully assessed.
Tasman District Council Biosecurity staff have visited a number of other sites in Tasman where naturalised spread is just starting to manifest. We are not too late at this stage to attempt eradication, but we need the support and cooperation of our local communities to achieve this goal.
It is important that Council is notified of sites where Taiwan cherry is, or has been planted in the past, as seedlings may have spread from these locations to neighbouring properties. The property occupiers around a Taiwan cherry site will need to remain vigilant and know how to identify and remove seedlings for a number of years (seed viability is unknown, but is possibly no more than 5 years).
We appreciate that these trees are attractive and that they draw in tuis and bees, but these benefits are far outweighed by the disastrous ecological impacts this tree will have on our indigenous scrubland and forest ecosystems if left to spread.
The Nelson-Tasman Regional Pest Management Plan 2019-2029 seeks to eradicate this tree over the life of the Plan, and it is now illegal to sell propagate or distribute Taiwan cherry in the Tasman-Nelson region.
To report a Taiwan cherry tree or for further information phone or email the Tasman District Council or the Nelson City Council.
Tasman District Council: Phone 03 543 8400
Nelson City Council: Phone 03 546 0200
Biocontrols refers to biological control agents that are brought in to reduce the vigour and viability of widespread pests. It requires extensive research and careful testing to ensure that only that the target species of weeds are affected.
Landowners are responsible for managing pests that are listed in the Regional Pest Management Plan, on the land that they own.