How a forest grazing project doubled a suckler herd
Grazing area and quality is improved with the use of virtual fencing on Abernethy Forest Nature Reserve © Mike Butler The ability to graze thousands of hectares on the Abernethy Forest Nature Reserve, in the Cairngorms, has provided beef farmer Bobby Mackenzie with low-cost outwintering and allowed him to double cow numbers to 200.
Abernethy is one of the Royal Society for the Protection of Birds’ (RSPB) largest reserves, at nearly 140sq km.
The charity has been working to restore biodiversity there in multiple ways, with a focus on improving and expanding the 5,000ha (12,355 acres) of forest.
See also: Benefits of switching to cattle and virtual fencing
Farm facts
The Glebe, Boat of Garten, Cairngorms National Park
Bobby Mackenzie © Bobby Mackenzie
- Tenants of the Seafield Estate
- Farming a total of 12,140ha, including grouse moors
- 4,000 Blackface and Cheviot ewes
- 200 native bred cows, with half grazed on the Abernethy Nature Reserve
- Most calves sold as yearlings; 30 finished a year
Capercaillie numbers
In 2019, RSPB Scotland identified the potential role of cattle in helping with forest restoration, and particularly in elevating dwindling capercaillie numbers by creating a more dynamic habitat.
Grazing cattle would disturb the forest floor, allowing tree seeds to reach the soil and germinate.
Dung would also help nutrient recycling, while grazing grassland would prevent vegetation from becoming rank and less attractive to breeding black grouse.
Conservation grazing by cattle has helped increase capercaillie numbers in Abernethy Forest © Richard Mason
Grazing offer
Local farmers were approached to take part in a 10-year RSPB project to assess the ecological benefits of grazing cattle. This would be compared with no intervention and cutting.
At the time, Bobby had 100 cows outwintered on fields earmarked for ploughing and fed silage.
Taking part in the project meant cows could be grazed rent free on the nearby reserve, with the charity paying for any supplementation of concentrates or mineral licks when needed.
Bobby, who farms with his dad, Robert, and sister, June, would supply, deliver and check the cattle and provide straw if necessary. He says it was an attractive offer.
“I was looking for a way to winter a specific type of cow really cheaply. That was my end goal,” he says.
The first year was a trial to see whether cattle would perform in the forest and benefit the habitat.
Rather than risk cows losing body condition, they started with 15 native-bred yearlings. These grazed in the summer on a 20ha (49-acre) block, which was fenced by hand among the trees.
“The cattle did fine. They didn’t come out fat, but they came out well enough [for me] to be willing to try it with the cows,” Bobby says. Dung samples showed there was no impact on faecal egg counts.
RSPB Scotland quickly saw the benefits in increased capercaillie numbers so increased the grazing area.
In 2021, the farm fenced 202ha (500 acres) – mainly under trees – for 35 mostly Aberdeen Angus-cross and Hereford-cross cows to graze from October to February.
They were supplemented with concentrates for three months from December, plus mineral blocks.
Five animals had to be pulled out as they lost too much condition in the harsh winter, but the rest maintained a body condition score of 2.5 to 3, Bobby says.
Use of GPS collars has increased the area of grazing for cattle © Bobby Mackenzie
Virtual fencing
Cow numbers increased to 45 over the next two years. RSPB Scotland then suggested using virtual fencing, including marginal grazing on open moorland.
This technology appealed to Bobby because it would increase the area and quality of accessible grazing.
The collars (costing about £250 each, plus annual subscription), supplementation and handling facilities have been funded by RSPB Scotland through a pre-Brexit EU grant and a private anonymous donor.
The charity plans to apply for a Sustainable Management of Forests – Woodland Grazing grant for further funding.
Cattle are trained with the GPS collars in a fenced field on the home farm.
On the first day, Bobby fits the collars. On the second day, the virtual boundary is set the same as the field boundary, and on day three or four, the field is split using a virtual GPS line.
Bobby says cows learn the warning signals quickly and are ready to go up to the reserve after a week.
The technology has allowed him to increase cow numbers to 200.
As not all stock is suitable for grazing on Abernethy, about six groups totalling 140 head are on the reserve.
The agreement with the RSPB means wormers can only be used on individuals grazing the reserve when essential, however, this has largely been unnecessary.
As a result, Bobby has reviewed routine wormer use on the home farm and now only worms when necessary.
Lessons from outwintering cattle in remote areas
1. Choose the right age of cattle
First and second calvers and cattle over 10 years old struggle in marginal areas.
Bobby Mackenzie only outwinters four- to 10-year-olds in the Abernethy Forest Nature Reserve.
2. Select the right type of cattle
Good temperament is needed for changing the collars.
Cows also need to be good on their feet. Bobby believes a robust, smaller cow of about 600kg with lower feed requirements is more suited than a larger, 800kg animal.
Only spring calvers are outwintered as autumn calvers require more feeding to get back in-calf.
3. Start small
It can be daunting dropping a group of cattle into a remote area. Start small and grow into it. It is also easier to address issues in a smaller group, should they arise.
4. Virtual fencing can be a challenge with calves
Animals must be large enough to wear a virtual fencing collar. This means there is a risk younger calves (not wearing collars) can wander off.
5. Battery life needs to be considered with virtual fencing
The collars are powered by a solar panel and have a battery life of about three months, although this varies depending on time of year.
Bobby and Abernethy conservation manager Richard Mason tend to wait for one-third of collars to lose battery and then gather and change the batteries all at once. (This method would not be possible if cattle were close to roads.)
6. Look out for ticks
Consider the risk of tick-borne fever in remote, overgrown grazing areas and monitor for issues. Bobby has not experienced problems.
Source: Bobby Mackenzie and Richard Mason
Conservation win-win
Bobby says the experience has changed his opinion on conservation.
“It’s opened my eyes to the conservation side. One, I think it’s a good thing and two, if you do it right, everyone can win,” he says.
RSPB’s conservation manager at Abernethy, Richard Mason, says the project has been a great success, resulting in an increase in capercaillie numbers from 18 to 30 males.
Lekking black grouse numbers (displaying courtship rituals) have also tripled.
Forging positive relationships with the local farming community has also been a huge win, and the reserve is now working with two additional graziers, also using virtual fencing.
This means 1,500-2,000ha (3,707-4,942 acres) are currently grazed, inside and outside the forest.
“I think each sector needs to be looking at ways to work together, especially where it can help nature and help food production.
Not only are we improving nature, we’re providing food and local employment and hopefully improving a local business,” Richard says.