UCT research tracks widespread illegal killing of rare bird of prey

University of Cape Town (UCT) academics have led an international study that has found that many young hen harriers in the United Kingdom (UK) are likely being illegally killed in areas that are used for the shooting of red grouse.

The hen harrier, sometimes called the ‘skydancer’ because of its amazing acrobatic display in the breeding season, is one of England’s rarest birds and is legally protected. Illegal killing of hen harriers has long been thought to limit their population size, despite suitable habitat being available to support more than 300 pairs on English moorland.

Identifying the scale of the impact on harrier populations has been difficult because the killings occur in remote areas; evidence is likely to be destroyed; and successful prosecutions are rare.

The study showed the likelihood of hen harriers dying, or disappearing, was ten times higher within areas covered mostly by grouse moor, compared to areas with no grouse moor. The study revealed that 72% of tagged harriers were either confirmed or considered very likely to have been illegally killed.

This long-term study has enabled patterns of disappearances to be assessed across a large number of birds. It provides overwhelming evidence that illegal killing is occurring on some grouse moors, where some gamekeepers view hen harriers as a threat to their grouse stocks. Grouse shooting, the hunting of the red grouse, is a popular sport in the UK.

Published recently in Nature Communications, this paper represents the culmination of a 10-year study involving 58 satellite tagged hen harriers. The analyses have been led by UCT and Aberdeen University with tracking data being provided by the English conservation agency, Natural England, and land use data by the conservation NGO, the Royal Society for the Protection of Birds.

“When people think about wildlife crime they often think about elephant and rhino poaching in Africa. However, wildlife crime is a global issue and even in developed countries like the United Kingdom, these activities can cause conservation problems for wildlife.”

Dr Megan Murgatroyd, a postdoctoral fellow with the Raptor Research Programme of UCT’s FitzPatrick Institute of African Ornithology, and lead author of the study, commented: “Whilst dead harriers can be disposed of, the pattern of hen harrier disappearances revealed by these data could not be hidden. The multiple levels of analyses of the data have all led to the same robust conclusion that hen harriers in Britain suffer elevated levels of mortality on grouse moors, and this is most likely the result of illegal killing.”

Associate Professor Arjun Amar, also from the FitzPatrick Institute, who supervised the research, added: “High levels of illegal killing have long been suspected on English grouse moors; with this study we have been able to show just how widespread the issue is, and that even within protected areas illegal killing seems to be a major problem for this species.

“When people think about wildlife crime they often think about elephant and rhino poaching in Africa. However, wildlife crime is a global issue and even in developed countries like the United Kingdom, these activities can cause conservation problems for wildlife. We hope that our research can help find a way forward to address this major conservation conflict.”