Saving the grey partridge
In England the Game & Wildlife Conservation Trust reversed the decline of the grey partridge by working with landowners to recreate habitat. With some adaptation, could the model allow our broadacre farms to become high-value hunting destinations?
One estate in an area of Sussex, England, has reinstated a sustainable wild grey partridge shoot by improving habitat provision and instigating predator control.
On this estate, grey partridge breeding density increased from 0.3 pairs per 100 ha in 2003 to nearly 20 pairs per 100 ha in 2010, making sustainable shooting possible, with the funds generated helping to offset the costs of management.
The decline of the grey partridge began after World War II and their numbers plummeted by 80 per cent in 40 years. The Sussex Study tracked the decline from 1968 with the Game & Wildlife Conservation Trust (GWCT) doing extensive research into both the causes of grey partridge declines and the methods it employed to reverse these declines.
Dr Nicholas Aebischer is deputy director of research at GWCT and he detailed the case study at the Conservation through Sustainable Use of Wildlife conference in Brisbane last September. “Through the Sussex Study my colleague Dick Potts demonstrated that the primary cause was agricultural intensification and this worked in several different ways,” he said. “Increased mechanisation led to the enlargement of fields and the removal of field boundaries, which destroyed nesting habitat resulting in poor holding capacity for the grey partridge. “Then the use of pesticides on crops reduced the number of chick feed insects in those crops, which led to poor chick survival. Finally, increases in predators and shrinking habitat meant greater predator pressure, leading to adult and nest losses.”
Dr Aebischer said of the three, the chick survival rate was the most important. A survival rate at or below 34 per cent meant overall numbers were declining.
The first solution devised was the conservation headland, a relatively thin margin on the edge of cereal crops where chicks most commonly feed. While farmers in the study area still sewed crop in the margin, the use of pesticides was restricted to those targeting specific weeds the farmers wouldn’t tolerate.
Lesser weeds and wild flowers were able to remain, attracting insects and therefore providing feed for chicks in the crucial first few weeks after hatching.
For eight years the research continued across 20 farms on the Sussex Downs. Half was farmed conventionally and others introduced conservation headlands. “It left in the understory the weeds that support insects and will provide food for chicks,” Dr Aebischer said.
“In five out of the eight years the survival rate exceeded the magic figure of 34 per cent while on the other half the survival rate never reached that minimum level.”
The next step was to address the rest of the grey partridge life cycle and develop a system that would provide cover for protection of adults and nests, and plentiful food.
Beetle banks worked, providing refuge, escape cover and food but the main
drawback was that the fingers of habitat reduced the land available for agricultural production.
The UK model was able to tap into European Union schemes, which compensated farmers for production foregone in order to implement environmental stewardship.
The final key to saving the grey partridge was predator control. “We aren’t sentimental at GWCT; the only solution is targeted culling of predators, but we do believe in science,” Dr Aebischer said.
A seven-year crossover study of spring pairs proved that the rate of decline slowed significantly through targeted culling.
In combination, predator control and habitat increased the number of spring pairs across the managed area from three in 2003 to 202 in 2010.
The Duke of Norfolk became heavily invested in the scheme, applying the principles to areas of his estate that were formerly farmed under lease.
In 2010 the Peppering Shoot in West Sussex won a Purdey Award for Game and Conservation.
In just seven years, spring partridge pair counts rose from three to 262, allowing a bag of 56 wild greys to be made in October 2010. Even with the reintroduction of regular shoots, the number of breeding pairs has since climbed to 350. “He can now shoot birds, which was his primary motivation for doing the works,” Dr Aebischer said.
“It not only brings great pleasure and a source of food for his family and friends, it provides revenue that allows him to pay for the keepering.”
It also answers in the positive the question as to whether hunting and species conservation are compatible.
A broader set of numbers returned on 3300 sites that are part of the UK’S Partridge Care Scheme also backs sustainable harvest as a key part of the value chain that underpins conservation and habitat management. “Where shooting doesn’t occur there was an 18 per cent decline, better than the national average but still a decline,” Dr Aebischer said. “In areas where you have that shooting interest, the increase is 91 per cent, so the grey partridge population has nearly doubled since 2000.”
In practice, the same landscape and predator management methods could be employed to build sustainable populations of quail in Australia but the sticking point would be compensation to offset lost production until sustainable populations could generate revenue from passionate hunters. “Quail in Australia would be much closer to the situation for grey partridge; you could hunt them sustainably where they are managed,” Dr Aebischer said. “It would need regulatory change but there really are cases where shooting and conservation can go hand in hand.”
“Then the use of pesticides on crops reduced the number of chick feed insects in those crops, which led to poor chick survival. Finally, increases in predators and shrinking habitat meant greater predator pressure, leading to adult and nest losses.”
Dr Nicholas Aebischer
Wild flowers growing in the margin of this field attract insects which young chicks feed on.