The Department of Conservation has culled more than 6000 tahr in the past six months. (File photo)
The Department of Conservation and Land Information New Zealand have taken to the skies to count the number of tahr on Crown Pastoral Land.
The first ever survey of the Himalayan mountain goat on such land, follows a major cull programme which has occurred in two stages throughout the year.
Thirty Crown pastoral leases within the tahr feral range are being surveyed as part of the exercise which began last week and is expected to take a month. The survey was meant to happen earlier this year but was postponed because of Covid-19.
DOC tahr programme manager James Holborow said the survey is “essential’’ for planning future work to manage tahr populations.
“Tahr are highly mobile and can easily migrate between land boundaries,’’ he said.
“During control operations, we have regularly found multiple mobs of up to 20 tahr on public conservation land near Crown pastoral leases.’’
Holborow said the majority of control inside the tahr feral range management units is now complete for the 2020/21 financial year.
“Crews are currently undertaking up to 30 remaining planned control hours, but this work is weather dependent,’’ he said.
He said DOC expected to publish updated control maps and data during November.
“And we will be able to provide analysis and discuss the next steps of engagement with tahr stakeholders at this time.”
Between July and September, DOC culled more than 6000 tahr in national park land and Crown-owned land. The Himalayan Thar Control Plan, which became active in 1993, stipulated there should only be 10,000 tahr within the “feral range” and no tahr on national parks.
While hunters value tahr as a trophy animal, the animal is also known to destroy and eat native plant life on national parks.
Land Information New Zealand deputy chief executive crown property Jerome Sheppard said a plane with high resolution cameras will estimate tahr numbers and mob sizes on the Crown pastoral leases.
“This aerial survey will help paint a clearer picture of tahr across the tahr feral range, as previously there have only been estimates of tahr numbers on public conservation land,” Sheppard said.
“Many of our leaseholders regularly carry out tahr control to limit their numbers as a condition of their lease, but the survey may reveal some could need to carry out further control.”
He said the organisation is working closely with leaseholders and DOC to manage the impacts of tahr on Crown pastoral land.
“As tahr know no boundaries, we feel it’s important we work together to monitor and control their numbers, as it’s just a hop, skip and jump over the fence,” he said.
Sheppard said Linz worked closely with leaseholders in monitoring tahr, but this information did not contribute to an official record of tahr numbers on Crown Pastoral Land.
“The survey will provide us with more information to get a more thorough understanding of tahr numbers on Crown Pastoral Land. We are looking at how we can better monitor and control tahr by working more closely with leaseholders and DOC,” he said.
He said controlling tahr takes a collective effort from all parties involved.
“Only by working together can we make sure that tahr numbers are managed across their favoured habitats.
“All lessees are expected to protect the inherent values present on Crown Pastoral Land, which includes managing browsing pressure. If tahr numbers are determined to be an issue, LINZ and DOC are committed to working with lessees to support control work.”
Survey results are expected to be released early next year.