Identifying issues and devising solutions

Much GWCT research has broad relevance beyond gamebirds.

Insect declines on farmland require widespread adoption of new measures, but our work points the way. Understanding what is driving predator numbers and finding solutions to predation requires good science.

The Review provides an insight into the breadth of research conducted at the GWCT. Although some projects may seem quite niche, some have very broad relevance to conservation. During the last three to four years we have heard increasing concerns about insect declines and the prospect of ‘insect armageddon’. This is a worry because insects play so many roles in ecosystems, from decomposition and nutrient cycling to pollination and providing food for birds, bats and small mammals. Our Sussex Study on the South Downs provides a unique dataset on insects on arable farmland, so an analysis in 2021 of trends in insect abundance and diversity since 1970 was timely. The article on pages 40-43 describes these trends and presents long-term monitoring data from our Allerton Project at Loddington, along with short-term sampling results from 10 other farms. It makes sobering reading: chick-food availability for grey partridges in cereal crops is typically half the level required for population stability. More surprisingly, most conservation habitats at field edges are failing to produce sufficient insects.

It is not too late to address the situation. At the Allerton Project, the field edges supported sufficient chick-food, demonstrating that sensitive management pays off. The latest results of our long-term bird monitoring show 76% higher Biodiversity Action Plan species abundance in 2021 than the baseline year in 1992 (see pages 48-49). The performance of our Advanced PARTRIDGE mix, developed at Rotherfield through our EU Interreg PARTRIDGE project, is particularly encouraging, having outperformed all conventional mixes for insect abundance in the last four years. It is now part of a Defra Test & Trial.

Our work on addressing predation also has broad relevance. March 2021 saw Jonathan Reynolds retire at the end of a distinguished career which included work on fox ecology, the impact of predation and its control on wildlife populations, and development of the GWCT mink raft and a Defra CoP-compliant fox snare. The projects conducted by Jonathan and his team exemplified the considered, scientific approach necessary to providing evidence and developing solutions to address controversial issues. We are building up our predation team again and focusing on what is driving predator numbers in the countryside. In recent years we have used GPS tracking and trail cameras to demonstrate the high density at which foxes can occur and determine habitat use (see Review of 2017, pages 14-17), and to quantify the impact of predators on declining waders (see pages 66-67). There is now much speculation, though very little evidence, that released gamebirds are supporting increased numbers of some predators. As part of our work on drivers of predator numbers, we initiated a PhD study with Bournemouth University in autumn 2021 employing genetic and stableisotope techniques to examine fox population dynamics. Andrew Hoodless, Director of Research

We are looking to quantify the impact of predators on declining waders, such as curlews. © Mike Short/GWCT