The Sika Foundation obtained sponsor funding and support to embark on a groundbreaking sika stag movement study in 2024. A total of eleven sika spikers were fitted with Iridium satellite tracking collars between May and July 2024. Data fixes of time, date, location and temperature are obtained at four-hourly intervals (six times per day) and uploaded to the satellite daily. These can then be downloaded and mapped to allow daily and seasonal movements to be tracked. At least 10 of the spikers were 1+ stags (rising 2yo) targeted while still in family groups on their birth ranges, while one is thought have been a 2+ stag (rising 3yo) at capture.

Why?

The Foundation seeks to understand how far sika spikers disperse from where they’re born, where they set up their rut grounds relative to their birth ranges, and where they set up their summer feed grounds relative to their rut grounds. This information will help navigate how optimal sika stag habitat might best be managed into the future – whether that be through a Sika Herd of Special Interest (HOSI) or in consultation with interested landowners.

Where?

The Foundation negotiated access to some 15,000ha of private Central North Island wilderness with a mix of beech, manuka, tussock, plantation and pasture habitat where landowners were supportive and shared common values around a desire to better understand and look after this valuable resource.

What Have We Learned So Far?

Of the 11 sika spikers originally collared between May and July 2024, 10 were still alive with functioning collars as of April 1, 2025. One collar had failed, and communication was lost despite manual ground searches and an extensive aerial  search. The remaining collars had been transmitting data for up to 10 months, with a variety of home range use patterns emerging over time.

The attached images show three distinct patterns that typify the movements of the sample of collared animals so far. The green dots are actual GPS fixes while the pink lines are automatically filled in by the tracking programme between four-hourly fixes. These pink lines do not necessarily equate to the actual path of movement by the animal.

One of the most interesting patterns is a large-scale dispersal away from the capture point (denoted by the yellow pin) shown in Image 1. After spending the winter and spring around his capture point, in December 2024, this young stag undertook a 50km journey over a three-week period travelling north through a mixed native and pine forest to a completely new location. He then settled in a very discrete area for three months, some 35km from where he was initially collared. As the rut approached, his movements once again started to increase.

The second pattern is from a young stag who moved to a very discrete range after capture and stayed there all winter into early spring. We suspect he got a bit of a fright and went home to hunker down with mum. During the spring, a distinct shift in his range occurred as he moved back out into more open feed areas where his range overlapped with two other collared stags. Our interpretation of this pattern is that the lower right-hand cluster of fixes represents his mother’s home range (where he was born). He appears to have made a number of return visits to this range through spring, but the majority of his fixes have been 2-3km away.

The third pattern represents the majority of collared stag movements, with a core range not far from where they were collared, punctuated with forays further afield. Of particular interest in Image 3 is the ~5km movement west where he hit a deer fence, was unable to go further, and returned to his core range.

The two months (April/May) over the traditional sika rut will be of intense interest. Where stags go, or if they stay where they are, will help inform our understanding of how sika stags use this complex landscape. Only time will tell. There is still so much more to learn.

Our sincere thanks go out to all our sponsors and supporters:

• Helisika
• Stoney Creek
• NZDA National
• NZDA Auckland Branch
• Safari Club International (NZ Chapter)
• Sika Hunters NZ
• Kai Waho Experience
• Poronui Station
• Lochinver Station
• East Taupo Lands Trust
• Plus, a number of other supporters who wish to remain anonymous.

We’ll continue to keep an eye on these stags and update the sika hunting community on further progress.

How Can You Help?

Please DO NOT shoot collared stags! These stags might turn up anywhere in coming years, so please carefully identify your target. You can also support our work by becoming a member of the Sika Foundation or making a donation.