Case study: Grey partridge recovery

Exploring the decline

Grey partridge pairThe grey partridge is a key species of interest to the GWCT. Our study of this much-loved gamebird – otherwise known as the English partridge – has unlocked many of the mysteries surrounding the declines of all our farmland birds since the Second World War.

Often described as an archetypal farmland bird, the grey partridge is very sensitive to changes in land management. In recent decades, both numbers and range have declined enormously. So much, in fact, that it is now on the UK Birds of Conservation Concern Red List. This decline began in the 1950s when the UK’s agricultural industry started to intensify. As well as increased production, mixed arable and livestock farms were replaced in the west by all-livestock farms and in the east by all-arable farms.

Counting partridgesSince 1967, the GWCT (and previously as the Game Conservancy) has been trying to understand the root causes of the decline. Long-term monitoring and large-scale experiments have been vital in unravelling what’s going on, and these were followed up with applied research to develop practical solutions.

Carrying out separate experiments and studies over a number of years, it was discovered that three main elements were the most important for grey partridge conservation: there were not enough areas on modern farmland for grey partridges to build nests; they were very vulnerable to predation from common predators, such as foxes, crows and stoats; and if they survived predation, found somewhere to nest and hatched their chicks, most new-born partridge chicks were starving to death because there were not enough insects to feed them.

Demonstrating the solutions

Beetle bankHaving identified the reasons for grey partridge decline, the GWCT then started looking for solutions. Working with land managers, solutions to the three main issues were trialled: building beetle banks to provide space for nesting; predator control to allow the birds to breed successfully; and conservation headlands and insect-rich field margins to provide insects for the chicks. These became the key elements for conservation.

Each of these elements was examined experimentally and on their own. Now we needed to put them all together in the same place and at the same time. An area of farmland, comprising six farm holdings, was set up to demonstrate these elements in action. The farmers involved were encouraged to manage their land to increase the amount of cover for the birds, where possible linking in with existing agri-environment options subsidised by the government, and create insect-rich brood-rearing areas. A gamekeeper was employed to carry out legal control of predators that kill adult partridges or destroy their nests during the breeding season, and to provide wheat grain in hoppers throughout the winter months and early spring to ensure the birds had sufficient food to see them through the lean months.

Over the five years of the demonstration, partridge numbers increased more than five-fold in the managed area, while in adjacent land, which hadn’t had any predator management or feeding, and little sympathetic habitat management, numbers doubled. In other words, the practical outcomes of the research were an overwhelming success!

Science into policy

Although the GWCT data clearly showed how severe the decline in grey partridge population was back in the 1970s, it was not until the mid-1990s that government, the conservation community and farmers realised the plight of our farmland birds – not just for grey partridges, but for other widespread species such as lapwings, tree sparrows, turtle doves, skylarks and linnets. At this point, GWCT scientists were able to use their research findings to help design the agri-environment schemes (AES) that help finance farmers and land managers in putting in place measures to help halt wildlife declines.

Science into farms

Peter Thompson with clientsNow let’s flip the situation around and look at it from the land manager’s point of view. Imagine you’re a farmer who has signed up for an AES. Lots of farmers are brilliant conservationists, but there are many who know less, have little time to learn more, and have not had access to good advice. If you are one of the latter, you might go for one of the easier AES options, like grassy strips at the edges of fields. You may not know that wildlife has more critical requirements, like insect-rich areas in the summer. As a result, you’re not convinced that your AES is really helping deliver wildlife recovery.

This is where the GWCT scientists can help again, but now from the other side of the problem. They have produced materials that explain how to use AESs and other measures to help the grey partridge.

The GWCT also runs the Partridge Count Scheme (PCS), which originated in 1933 and relies on farmers to count their own wildlife. For many years its purpose was to monitor numbers and productivity of partridges through a network of around 900 farmers and gamekeepers at around 900 participating estates across the country. After the government nominated the GWCT as lead partner for the Grey Partridge Species Action Plan in 1996, the PCS was relaunched. As well as expanding the monitoring role, the scheme facilitates contact with gamekeepers, farmers and landowners to encourage more and better management through feedback.

In addition to working with individual farmers to identify solutions for their particular farm-holding, GWCT advisors bring together farmers in local areas through partridge groups that meet once or twice a year. This has promoted enthusiasm and opportunities for sharing information such as the latest research and changes in agricultural policy. It also allows the farmers to feed back to the GWCT on the practical aspects of implementing and managing AESs.

Covey of grey partridges (www.davidmasonimages.com)This approach obviously works and can have a massive impact. PCS data show that there was an 81% increase in partridge pairs on count farms between 2000 and 2010, whereas national figures for the same period show a decline of 40%. Although the counting methods used were different, the trends are still comparable. And it is not just the partridges that are benefiting from this approach. A GWCT study found that there were 24% more farmland songbirds and, on average, five more species on farms participating in the PCS compared with neighbouring farms. These outcomes show the huge benefit of knowledge exchange at its best – generating two-way conversations that help both sides.