The first nesting of Pallid Harriers in western Europe has occurred in the Netherlands this year, and the birds have fledged four young (all females). The birds were discovered by Willem-Pier Vellinga, a volunteer of the Dutch Montagu’s Harrier Foundation. This successful nesting of a rare species is only now being publicised at the end of the season and went unnoticed by the Dutch birding community because it occurred on standard arable farmland.
Video courtesy of RJ van der Leij/Ruben Smit Productions.nl
Vellinga discovered the male Pallid Harrier by chance while doing breeding bird counts in May (UK birders please note – sign up for a BBS square!) and it appeared to him that the bird showed breeding bird behaviour. Together with harrier expert Ben Koks the following day the breeding location was located in a parcel of winter barley.
The first egg was estimated to have been laid between 8 and 10 May.
A nest protection fence was put in place on 17 June. At that moment, five chicks of between three and eleven days old were in the nest. Without nest protection the chance of predation by beech marten or fox, that could hear the racket of the young, would have been high.
Besides protection from predation it was important to preserve the nest from the wind. With heavy rains and strong winds barley tends to tilt over and may bury the nest and its residents, the end of the breeding attempt. This was a real risk when wind and rain hit the fields of Groningen on 9 June.
The winter barley was harvested in early July. Staff and volunteers of the Dutch Montagu’s Harrier Foundation were on site to prevent the young from being killed by the combine harvester. Two of the young had already fledged; the other two could almost fly. The fifth chick had disappeared in the early chick phase. All four remaining young were females. The four were ringed, and also have black color rings with white inscription, just before they were able to fly. All four fledged young were flying strongly a few days ago (12 July).
Not that long ago, Pallid Harriers were rarities only spotted occasionally on migration in The Netherlands (and the UK). In recent years the number of Pallid Harriers observed during migration in The Netherlands (and the UK) has increased. In the last two years several individuals overwintered in the Netherlands.
Three years ago, a male Pallid Harrier was associating with a female Montagu’s Harrier near Finsterwolde in Groningen province. That didn’t result in anything. It remains a mystery where this year’s two breeding birds came from and how we could explain their appearance in Groningen. Interestingly, a male Pallid Harrier spent some time in Hen Harrier nesting habitat in the Forest of Bowland, Lancashire, UK, in late April/early May this year before ‘disappearing’ – as harriers often do in those parts – but I don’t think we have any solid evidence as to what happened to that bird.
The Pallid Harrier is still a rather mysterious species. The nearest documented breeding pair this year was near Oulu in Finland. The next breeding population is located in the steppes of Eastern Europe and Asia. The Dutch name for Pallid Harrier is Steppekiekendief – Steppe Chick Thief (Hen Harrier is Blauwe Kiekendief (Blue Chick Thief)).
While other harrier species feed primarily on voles, Pallid Harriers prefer songbirds, just like Sparrowhawks do. The Dutch Montagu’s Harrier Foundation also got to know Pallid Harriers as notorious bird hunters during expeditions to the wintering areas in India and Africa. The breeding male in Groningen was actually observed hunting on farm properties, catching Swallows, sparrows, Starlings and tits.
This blog is based closely on a press release from the Dutch Montagu’s Harrier Foundation with a few additions, omissions and slight changes of wording. I am very grateful to them all, particularly Ben Koks and Oike Vlaanderen, for the opportunity to bring this exciting news (and a good news story about harriers) to you. Many thanks too to the photographers for their images of these beautiful birds which have surprised us all by their breeding so far out of their normal range.
I wonder what will happen next year? the experience with lowland nesting Hen Harriers in England is that successful breeding in a lowland site one year is not a very good predictor of the birds returning to anywhere in the neighbourhood next year. Maybe next year it will be the UK? Or maybe it’s a complete one-off?
The Dutch Montagu’s Harrier Foundation describe this event as ‘One of the most magic events in ornithology that happened in our part of Europe during the last decades!‘ – quite right!
And to end, two images of food passes – the first of these Dutch Pallid Harriers and the second of Hen Harriers in the UK.