ANNUAL REPORT UNALIENATED CROWN LAND ANIMAL PEST CONTROL Financial Year 2008-2009 Prepared for Land Information New Zealand by Landward Management Ltd PO Box 5627 DUNEDIN June 2009
TABLE OF CONTENTS LIST OF LAND DEFINITIONS...2 1. INTRODUCTION...3 1.1 Priority Rankings...3 2. RESOURCE CONSENT COMPLIANCE...4 2.1 Regional Council Consent...4 2.2 Ministry of Health (MoH) Consent/Permit...5 3. LIAISON WITH LANDOWNERS...5 4. RABBIT CONTROL WORKS - CANTERBURY...6 4.1 Waipara River...6 4.2 Tasman River...8 4.3 Maerewhenua River...9 4.4 Waitaki and Otiake Rivers...10 5. RABBIT CONTROL WORKS - OTAGO...11 5.1 Lake Dunstan Shoreline...11 6. SUMMARY...12 APPENDIX 1...13 1
LIST OF LAND DEFINITIONS Crown Riverbed Crown riverbed in this document refers to land belonging to the Crown that is administered by Land Information New Zealand (LINZ); referred to as Unalienated Crown Land (UCL). Areas of UCL requiring pest management were identified using the following criteria: Areas of braided riverbed bounded on both sides by marginal strip or road reserve. Areas of braided riverbed bounded on one or both sides by land not subject to ad medium filum (AMF) rights. 1 Marginal Strip Marginal Strip in this document refers to lands of the Crown administered by the Department of Conservation (DoC). Road Reserve Road Reserve in this document refers to land administered by territorial authorities (District Councils or Unitary Authorities). Application of these criteria is considered appropriate because it is expected that these particular areas will require the greatest attention for pest management. Other areas may be identified in the future, but they are less likely to have a high priority for pest management. 1 Where a river abuts a property and connection is not interrupted by a legal road, the adjoining landowner may own the riverbed to the middle of the river. These are called ad medium filum rights. This situation is more prevalent in South Island braided rivers. 2
1. INTRODUCTION Land Information New Zealand has responsibilities for managing the control of pest plants and animals on UCL, on behalf of the Crown. In most cases, Crown riverbed comprises areas of braided river or stream beds bounded on both sides by marginal strips or road reserves. The main animal pest that occurs on UCL is the rabbit (Oryctolagus cuniculus). Rabbits can pose serious threats to adjoining farmland and conservation areas. Regional Pest Management Strategies (RPMS) have been developed under the Biosecurity Act 1993 by Regional Councils to deal with pest plants and animals, including rabbits. Some pests have been categorised according to their threat to economic values, while others have been listed as threats to conservation values. Control of rabbits on UCL is therefore an important aspect of the Crown s land management programme. The aim of rabbit control is to reduce infestations to low levels, after which only periodical inspection and maintenance control is required. Landward Management Ltd. (Landward) is the contractor responsible for managing and coordinating biosecurity operations (pest and weed control) on UCL, for LINZ. This role includes the following tasks: Preparation of annual weed/pest control programmes Preparation of tenders and contracts for engagement of weed/pest control contractors Monitoring and inspection of operations Monitoring resource consent compliance Annual reports on operations Reporting on other issues which may be of relevance to biosecurity operations. This report outlines rabbit control operations scheduled on UCL in the South Island in the period 1 July 2008 to 30 June 2009 financial year. However, some control operations may need to be extended into July 2009 due to weather delays. Operations included: Aerial application of poison (1080) carrot in the Tasman River Ground application of poison (1080 and pindone) carrot 1.1 Priority Rankings Sites to be treated are selected on the basis of feedback from the appropriate Regional Council. Regional Councils employ biosecurity staff and contractors to 3
inspect rabbit prone sites. If it is found rabbit numbers are non-compliant with levels set out in the RPMS, an Inspection Advice is sent out to the land occupier stating that rabbit control is required. Should the control work not be undertaken, a reinspection is carried out, followed by a Notice of Direction stating that rabbit control must be undertaken. Should a private landowner still fail to carry out control on the pest and reduce it to compliant levels, then the Regional Council may carry out action on default, which means that the Council arranges for the work to be done but the cost for the control is passed on to the land owner. The levels set in the applicable RPMS, above which rabbit control is required are: Marlborough Rabbits must be below Modified McLean Scale (MMS) Level 4 in the upper Awatere/Clarence area, and Level 3 in the rest of the district Canterbury - Rabbits must be below MMS Level 3 Otago Rabbits must be below MMS Level 3 The Modified McLean Scale can be found in Appendix 1. The Crown is not bound by RPMS, and therefore any Inspections Advices or Notices of Direction are non-binding. However, the Crown seeks to act as a good neighbour and therefore does plan to control rabbits on its land that is under Notice of Direction. The rabbit control still needs to be prioritised, with priorities as follows: The ability to define area as UCL; Compliance with the RPMS. High priority was also accorded areas where adjacent landowners had grouped together to form a wider rabbit control programme, which may include UCL. In these circumstances, LINZ, being a responsible land holder, would act as a good neighbour and contribute to the wider rabbit control programme. The lowest priority was given to areas where landowners had no defined programme to control adjacent areas. Prior to control works occurring, it was important for LINZ to establish what part of the riverbed is UCL, and what is subject to AMF-rights. With this in mind, status checks were commissioned to establish this. Where an adjacent land owner has taken up AMF-rights, they are expected to carry out pest control to the centre line of the riverbed. 2. RESOURCE CONSENT COMPLIANCE 2.1 Regional Council Consent Resource consents to allow the application of 1080 and/or pindone poison in circumstances where it may enter water in the Canterbury region were required prior 4
to any control works taking place. These consents had to be gained for each site where LINZ planned to carry out control. Control works in Otago were away from water and are a permitted activity under the Otago Regional Water Plan. Environment Canterbury had previously informed LINZ that they did not consider any other party to be affected by the application of 1080 or pindone and therefore no approvals from other parties was required. Despite this, consultation continued with Ngai Tahu and Papatipu Runanga, and conditions on the LINZ consents were requested to be in line with what was agreed through consultation with Ngai Tahu last season. The resource consents were issued on the following dates: Tasman River (CRC093320) 21 May 2009 Waipara River (CRC093583) 26 May 2009 Waitaki/Otiake Rivers (CRC093584) 21 May 2009 All of these consents were issued for a period of 10 years. The Maerewhenua River control was carried out under an existing consent (CRC073615). Any new areas identified by ECan as requiring rabbit control in the future will also require LINZ to gain a resource consent. It is anticipated that future consents will be streamlined as a result of the consultation process from the 2007/08 season. 2.2 Ministry of Health (MoH) Consent/Permit The MoH must also approve the use of some vertebrate poisons prior to their discharge due to the risk to human health. The use of pindone for rabbit control does not require MoH consent, however 1080 use does. Prior to any rabbit control using 1080 being carried out, the contractor arranged for the MoH permit to be issued and during control contractors were required to comply with MoH conditions as detailed in the permit. 3. LIAISON WITH LANDOWNERS Land Information New Zealand has undertaken to consult with the following parties when developing and planning the rabbit control programmes: Marlborough District Council (MDC) Environment Canterbury Otago Regional Council Department of Conservation Fish and Game 5
Adjacent Landowners to where control is planned to take place Inspections of a number of properties adjacent the UCL also allowed continued liaison with individual landowners. Support from landowners for LINZ rabbit control has been very positive. Prior to control works being started, other parties that were informed included, District Councils, local schools, local police, Fonterra, Forest and Bird, Fish and Game and any other local person or organisation that may use the area. 4. RABBIT CONTROL WORKS - CANTERBURY 4.1 Waipara River A Notice of Direction was first issued for the Waipara River on 18 March 2009, which required control to be carried out in an area of the Waipara riverbed between The Deans approximately 11km upstream of State Highway 1 (SH1) and Yellow Rose approximately 2km downstream of SH1. A number of adjacent land owners also received a Notice of Direction to carry out rabbit control. Prior to work commencing, a status check was commissioned to determine land tenure. The status check identified significant areas of the riverbed as being subject to freehold interests and therefore the regional council was advised that LINZ would not carry out rabbit control on those areas. Approximately 110ha was still identified as being subject to Crown interests. Following grant of the resource consent, rabbit works started on 23 June 2009 with the first feed of pindone carrot applied over the Crown riverbed and also on adjacent properties under Notice of Direction. The second application of pindone carrot was scheduled for 27 June 2009. At the time of writing this report it was too early to determine the results of the rabbit control programme. 6
Figure 1. LINZ rabbit control areas on the Waipara River. Only areas of confirmed LINZ administered UCL are shown in pink. 7
4.2 Tasman River A Notice of Direction was issued for the Tasman River on 1 December 2008, which required rabbit control to be carried out over a large area in the Tasman River north of Lake Pukaki. Although no other adjacent land owners received Notice of Direction to carry out rabbit control, the owner of Glentanner station indicated that he would also carry out some control in cooperation with LINZ. A status check of the Tasman River showed all areas where rabbits were under Notice of Direction were subject to the interests of the Crown. Rabbit control started on 18 June 2009 with the first pre-feed of non-toxic carrot applied over an area of about 2,500ha using a fixed-wing aircraft. The second prefeed application of carrot took place on 25 June 2009. The toxic feed application, which was 1080 carrot applied by both fixed-wing aircraft and hand broadcasting, was scheduled for early July so was yet to occur at the time of writing this report. Figure 2. Rabbit control area in the Tasman River. 8
4.3 Maerewhenua River A Notice of Direction was issued for the Maerewhenua River on 5 December 2008, which required rabbit control to be carried out between State Highway 83 and the confluence of the Maerewhenua River with the Waitaki River. This was an area of approximately 20ha. A status check of the area confirmed the entire riverbed as being subject to Crown interests. Following granting of the resource consent, rabbit control was scheduled to begin on 6 July 2009 with the first pre-feed, and scheduled to be completed on 21 July when the toxic 1080 carrot was due to be applied by hand broadcasting. Figure 3. Rabbit control area in the Maerewhenua River 9
4.4 Waitaki and Otiake Rivers Notices of Direction were issued for the Waitaki and Otiake Rivers on 5 December 2008, which required rabbit control to be carried out in the Waitaki River downstream of the State Highway 82 Road Bridge at Kurow, including the lower part of the Kurow River, and also in the lower reaches of the Otiake River including the areas around the confluence of the Otiake River with the Waitaki River. These areas are approximately 200ha. A status check of these areas confirmed all parts of the riverbed were being subject to Crown interests. Following granting of the resource consent, rabbit control was scheduled to begin on 6 July 2009 with the first pre-feed, and scheduled to be completed on 21 July when 1080 carrot was due to be applied by hand broadcasting. This site has experienced some media and public interest which has been dealt with directly by LINZ communications department. Figure 4. Rabbit control area in the Waitaki and Otiake Rivers 10
5. RABBIT CONTROL WORKS - OTAGO 5.1 Lake Dunstan Shoreline Land Information New Zealand received a complaint regarding rabbit numbers on the western shoreline of Lake Dunstan near where the Clutha River enters. An inspection was carried out over the area which confirmed that there were very high rabbit numbers and control would be necessary. Further inspection by the Otago Regional Council confirmed this and they proceeded to inform adjacent landowners as well that they too would need to control rabbits on their properties. This control was planned to be carried out in July/August 2008. However, Central Otago experienced a very mild winter last season that allowed the grass to continue to grow. This meant that the rabbits were not attracted to the carrot bait at all, as they continued to eat the grass. Rather than risk a major failure should control works proceed, it was decided to postpone control until the winter of 2009. This control is now scheduled to commence in early July, and should be completed before the end of July. Figure 5. Proposed rabbit control area along the shoreline of Lake Dunstan 11
6. SUMMARY Rabbit numbers have been steadily increasing throughout the South Island and Landward has been informing LINZ for some years that it was likely that some measure of control would be needed in future to control their numbers. The issuing of multiple Notices of Direction over the last 3 years has brought the issue to the fore and this has resulted in funding being made available for the control of rabbits. As a result of multiple areas being controlled last season, processes were in place to make the applications for resource consent run relatively smoothly, and also set into motion the other requirements to ensure rabbit control could proceed without any major issues. Unfortunately, at the time of writing this report, control works were only just getting underway, so results will not be known for a few weeks at the earliest. Some delays were being experienced due to unsettled weather and high river levels. However, apart from the weather delays, the rabbit control is expected to proceed relatively smoothly. It was pleasing that in most areas where LINZ is planning to carry out control operations, adjacent land owners are also planning their own control as part of the same operation. This meant that rabbits could more effectively be killed and there was less risk of reinfestation from neighbouring properties. There is the possibility that most of the rabbit population that was resistant to RCD will be killed by the poisoning and shooting. This would result in RCD being more effective in retaining low rabbit numbers for several years. It is important that follow up control is carried out at these sites. Rabbits are fast breeders, and can quickly build up numbers again. This can also be exacerbated by migration from other sites where no control has occurred. 12
Appendix 1 Modified McLean and Gibb Scales of Rabbit Infestation McLean Level Gibb No rabbits or sign seen 1 Very few droppings, sometimes grouped, easily overlooked No rabbits seen, some sign noticeable 2 Very infrequent heaps, little if any scatter Odd rabbit seen, sign and some buck heaps showing up Pockets of rabbits, sign and fresh burrows very noticeable 3 Infrequent heaps, very light and patchy scatter 4 Frequent heaps, light and patchy scatter Infestation spreading out from heavy pockets 5 Heaps occasionally within five paces of each other, moderate scatter overall Infestation over whole area, and increasing 6 Heaps often within five paces of each other, dense scatter Infestation heavy, rabbits moving in droves, pasture damage, warrens Infestation at high level throughout, severe pasture and vegetation damage 7 Usually two or three heaps within five paces of each other, dense scatter 8 Usually three or more heaps within five paces of each other, dense scatter overall Infestation almost at peak 9 Some heaps almost merging, scatter very dense Maximum level, rabbits must spread out over wide area or starve 10 Some heaps merging, very dense scatter overall 13