Flanders Moss NNR
Our second hen harrier count of the year took place last week – a much drier and brighter session than our first (see Ceris’ blog post “Winter Visitors to Flanders Moss”), but sadly, just as unfruitful a search for this elusive raptor – though we did have a lovely view of a male peregrine falcon! Indeed, it is an unfortunate time we find ourselves in when it comes to the hen harrier. Historically Flanders is a traditional wintering site, but for the last 5 years sightings have reduced, and the reasons for this can only be guessed at but are likely to be varied and complex.
One thing is we are noting more sightings during early autumn and spring, whereas previously they were more likely to be spotted mid-winter. Is this due to a changing climate affecting the way hen harriers spend their winter? It can’t be ruled out.
Another change? Flanders itself! As the restoration of this reserve continues, we are seeing the expected switch from drier heathland to a much wetter bog unfold. This vegetation shift, a reduction in trees used for roosting, and heavy grazing by deer in places, may have reduced habitats with suitable cover for roosting in and maybe for prey species. And less food will mean fewer predators.
Hen harriers are one of the most persecuted birds in the UK and their population has been removed from large areas of suitable habitat by illegal killing. Is there a link between hen harrier breeding grounds and their wintering grounds? Are the birds that traditionally breed is areas where they are persecuted the ones that winter on Flanders? We don’t know, but these are the sort of questions that can be answered by the continuation of fixing of satellite tags to young hen harriers.
Biodiversity, and it’s changes over time, can be highly complex. We cannot point to any one specific reason because it could be several of these – or none! These issues require extensive monitoring and analysis – and that is ultimately why we conduct our counts. They feed into a national long-term survey that provides a much wider picture of hen harrier sightings across Scotland, and should gradually provide useful insights into the why, and where, of hen harrier distribution. So in the meantime we will keep watching.
There is a clear scientific consensus that our world is facing a biodiversity crisis, and the hen harrier is just one example of this. Scientific research, monitoring, and partnership working – across all organisations and interests – are fundamental to conservation. Preventing the endangerment and extinction of Scotland’s flora and fauna, and ensuring a biodiverse and ecologically rich future, has never been more important. We all depend on nature, and nature depends on us.