Finnish Pallid Harrier wintered in Morocco in a rich, yet dangerous area

By MaghrebOrnitho | 22 July 2019

A Pallid Harrier satellite-tracked from Finland spent the winter in the Guelmim region, southern Morocco. The region is very rich in preys but also very dangerous for raptors because of electrocution. This is the first proven wintering record of Pallid Harrier in Morocco.

Westward expansion of the Pallid Harrier

Pallid Harrier (Circus macrourus) breeds in Eastern Europe eastward to Central Asia and winter mainly in sub-Saharan Africa and South Asia. The species has been expanding its breeding range westward despite its unfavorable conservation status (currently categorized as ‘Near Threatened’ in the IUCN Red List). This colonization of new breeding areas first started in Northwest Europe where it’s now a regular breeder in Finland, and then in continental Western Europe where the expansion is probably much slower (e.g. the first breeding record in the Netherlands was in 2017, and the second was in 2019. The first breeding pair in Spain was in 2019, the female of that Spanish pair is one of the fledglings from the Dutch pair in 2017).

This westward breeding expansion is accompanied by an increase of Pallid Harriers using the western flyway (via the Strait of Gibraltar) to their wintering areas in sub-Saharan Africa. In this regard, the number of records has been steadily increasing in France and Spain since 2004 (see the review by Ollé et al. 2015).

In Morocco, where birding effort is lower, there have been 64 records of Pallid Harrier (until April 2018, see the review by Bergier & Thévenot 2018). Here, the species has been observed mainly during spring migration, with only a few observations in autumn and almost absent in winter. Two birds observed in the southern Morocco in early February (one near Tantan on 2 Feb. 1992, and the other at Massa on 9 Feb. 2011) may have been wintering birds or early spring migrants (cited in Bergier & Thévenot 2018). However, until this season, there has been no proof of Pallid Harrier wintering in Morocco.

First wintering of Pallid Harrier in Morocco

On 1 July 2018, a breeding female Pallid Harrier named ‘Selja’ was equipped with a satellite transmitter in Siikajoki, central Finland by the Finnish Natural History Museum (LUOMUS). In late July, Selja started her post-breeding migration by going to northern Finland and then south through Sweden. The whole journey of Selja can be seen at this website (from where the following map was coppied)

The migratory routes of the Finnish Pallid Harrier ‘Selja’: green track in 2018, blue track in 2019. (Data of LUOMUS - the Finnish Natural History Museum).
The migratory routes of Selja: green track in 2018, blue track in 2019. (Data of LUOMUS – the Finnish Natural History Museum).

After some short stop-overs in the Netherlands and in southern Spain (Cádiz region), Selja crossed the Strait of Gibraltar to Morocco and headed towards a rich area east of Casablanca where it stayed about five days to refuel (photographed by Abdeslam Rihane, see tweet below). From there, she continued her journey towards the south and reached the region of Guelmim on 13 November.

Selja spent about a week in an area just south-west of Guelmim, and then decided to move south to West Africa (e.g. where another Finnish Pallier Harrier named ‘Potku‘ wintered two consecutive years). However, she quickly realized her ‘mistake’ and returned back to that same area south-west of Guelmim. Here, she spent the whole winter (almost 4 months) in a small area of about 5 x 15 kilometers.

The small wintering area of the Finnish Pallid Harrier ‘Selja’, the town of Guelmim in the north-west is visible (Data of LUOMUS - the Finnish Natural History Museum).
The small wintering area of Selja, the town of Guelmim in the north-west is visible (Data of LUOMUS – the Finnish Natural History Museum).

On 21 March 2019, she left her Moroccan wintering area and headed north via almost the same route. Once in Europe, she spent about two weeks in the province of Flevoland in the Netherlands in April, before continuing her journey.

Upon arrival to Finland, she settled near the Swedish border in a completely new area (located some 150 Km north from where she nested in 2018). There, she paired with a new male and by 14 June 2019 she already laid 5 eggs.

What’s special about that Guelmim area?

This Guelmim area is very rich in prey such as rodents and reptiles, and for this reason it attracts a large number of raptors from Morocco and Europe. However, the region is also very dangerous because of the high incidences of bird electrocution registered here during the past few years. It’s exactly in this area where Selja the Pallid Harrier spent almost four months. Our colleagues in Finland should be proud of her as it made it back ‘home’ safely.

For more information about bird electrocution in this area, read these references:

Selja the Pallid Harrier after her arrival to Finland, spring 2019 (photo by Ari-Pekka Auvinen via SuomenLuonto.fi)
Selja the Pallid Harrier after her arrival to Finland, spring 2019 (photo by Ari-Pekka Auvinen via: SuomenLuonto.fi)

References:

Bergier, P. & Thévenot, M. 2018. Le Busard pâle Circus macrourus au Maroc. Go-South Bulletin 15: 69-76.

Dutch Montagu’s Harrier Foundation, 2017. The Pallid Harrier, a new breeding species for the Netherlands. Nature Today, posted 14 July 2017.

Ollé, À., Trabalon, F. & Bertran, M. 2015. A review of occurrences of the Pallid Harrier Circus macrourus in the Western Mediterranean: a new migrant and wintering species. Revista Catalana d’Ornitologia 31: 7-14.

Thanks

To Alain Fossé for the updates about Selja, both when she reached Casablanca in autumn and when she started her spring migration. Thanks also to Ari-Pekka Auvinen for the photograph and to SuomenLuonto.fi from where I copied it.

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