An amazing admission by RSPB Scotland is reported on the Raptor Politics blog. On Orkney, between 1973 and the 1990s, the number of breeding female hen harriers crashed from 100 to just 3. That's right, a 97% drop. And not a gamekeeper in sight.
The crash is attributed to grazing by sheep - numbers doubled during the 1980s in response to CAP subsidies. Now the CAP subsidies have been reformed, sheep numbers have fallen again, and harriers are recovering.
Of course the RSPB still manage to get in the obligatory broadside: "Illegal disturbance and killing continues to be the main barrier to this beautiful bird returning to many parts of the country where it should be commonplace."
Nothing to do with excessive numbers of deer, sheep, etc then. Or militant do-gooders stravaiging all over the place during the breeding season. It's all the fault of those ghastly posh people and their wicked gamekeepers (cue green smoke, audience hisses).