Rabbits and your feedbase: Why warrens matter

Source: Centre for Invasive Species Solutions, 2025

Rabbits remain one of the most persistent pressures on pasture and regeneration across grazing landscapes, often limiting feed availability long before producers realise how big the problem has become.

Speaking at the most recent Feral Cat and Fox Management Forum, Aaron Stephens, Invasive Species Coordinator at Bass Coast Landcare Network, said rabbit biology explains why feed losses can escalate so quickly.

"Rabbits have a gestation period of about one month. The average litter is five to eight kittens, and those kittens reach sexual maturity in about three months," Aaron said.

"A rabbit that has just given birth can become pregnant again about half an hour later."

That breeding speed becomes a major issue when conditions are good. "When there’s lots of feed around, they can just breed continuously across the landscape," he said.

Even low numbers can cause long-term pasture damage.

"As little as one to three rabbits per hectare is enough to stop regeneration of many native species. When you’re looking at landscapes with hundreds of rabbits per hectare, nothing is going to survive and grow,” Aaron said.

For producers, the impact shows up as weakened pasture persistence, selective grazing of high‑value species like clover and perennials, and declining groundcover resulting in an increase in weeds.

"They destroy crops, they damage pastures and reduce overall productivity," he said.

One of the strongest messages from the forum was about reframing control targets.

"Is it achievable to have zero rabbits in a landscape like this? The answer is no," Aaron said. "Rabbits will always move in from surrounding areas."

Instead, Aaron encouraged producers to focus on what actually underpins rabbit survival.

"The warren is the rabbit’s Achilles heel. Without it, they can’t breed effectively and the young don’t stand much of a chance."

That principle underpins what Aaron calls the golden formula for rabbit control.

"You reduce the population, then you remove the warrens, then you follow up," he said. "If you skip that middle step, you’ll always be chasing rabbits."

He was blunt about partial control. "You could bait every year for the rest of your life and still have rabbits if the warrens remain," Aaron said. "As long as those burrows are there, more rabbits will move in and start breeding again."

Practical on‑farm steps to protect your feedbase

1. Start with pasture, not rabbits
   Identify paddocks where pasture isn’t regenerating properly, valuable species are disappearing, or soil erosion is increasing. These signs often appear before rabbit numbers look high.
2. Map active warrens
   Walk paddocks, fence lines, dam walls and creek banks to locate and record active warrens. This allows effort to be focused where it will deliver the greatest pasture benefit.
3. Reduce numbers before disturbing warrens
   Lower rabbit numbers first to increase the success of warren destruction. Use baiting in dry conditions, fumigation in targeted areas, and shooting as a clean‑up tool rather than a standalone solution.
4. Destroy warrens permanently
   Rip or excavate warrens wherever access allows, extending excavation at least 4m in every direction beyond the visible burrow entrances. Compact soil after ripping to prevent re‑digging. Although machinery has an upfront cost, it usually delivers long‑term savings and feedbase recovery.
5. Protect high‑value feed and assets
   Use rabbit‑proof fencing strategically to protect high‑value pasture, fodder crops, regeneration areas or infrastructure. Ensure fences are correctly designed at ground level and well maintained.
6. Follow up and monitor
   Recheck treated areas, respond quickly to any surviving activity, and keep basic records. Early intervention prevents small problems turning back into large ones.
7. Treat disease as a bonus, not a strategy
   Disease events may temporarily reduce rabbit numbers but won’t remove warrens or guarantee long‑term pasture recovery.

Bottom line for producers: reducing rabbit numbers helps in the short term, but removing active warrens is what delivers lasting pasture recovery, stronger pastures and better returns on rainfall and fertiliser.