Sunday, 2 February 2014

Satellite tagged bird update 31st Jan 2014

Hattie Grainne and Miranda, 29th-30th January 2014

Nothing new really, but this is interesting in itself. Miranda is loyal to a definable home range in County Mayo and Hattie and Grainne have rarely ventured beyond 7 km from their nests in Langholm.
Hattie and Grainne (below 22nd -30th January) are occasionally roosting communally but with little crossover in hunting range.

Grainne is hunting approximately 5-6km to the south of the main communal roost, concentrating on the heather clad slopes around her old nest and the birch and gorse scrub to the southeast. The mild weather has seemingly held some smaller passerines on the hill, presumably also reducing the overwinter mortality of the small mammals. Despite apparent high densities of prey species there is ongoing evidence of grouse predation in Grainne’s foraging range. Goshawk, peregrine and buzzard are also frequenting the area along with an adult male and at least one juvenile untagged female hen harrier.

Hattie’s chosen foraging area is away from the Langholm grouse moors, approximately 7km northeast of the roost in a mainly whitemoor area with clear felled areas (trees removed c5yrs ago). In December, she was arriving at the roost about 1540 hrs. This will get progressively later each day as the daylight lengthens. Seldom does she roost away from the main communal site.

Grainne is less particular about where she roosts, using at least three separate sites across her range including in recent days the communal roost "owned" by Hattie. Two of Grainne’s roosts are similar in habitat and topography to the English roosts, resembling a flat/saucer shaped wet Juncus area, usually less than a hectare in extent surrounded on at least two sides and shielded from the north by "low whaleback" hills.

Miranda is worthy of a special mention in this update. Using the logic that arrived at the name McPedro, she should now be called Mirandagh having now spent more time in Ireland than Scotland.

Resume of Miranda’s stay in Mayo

Miranda has now been in Ireland for approximately 14 weeks, spending the majority in Co Mayo (9 weeks). The following summarises her stay so far and highlights some important areas within her recent settled home range.

Miranda, nest to wintering ground in County Mayo July 2013 – January 2014

Miranda returned yesterday evening to a roost near Carrowmore, Lake County Mayo. This is at least the third night over the previous 9 weeks she has roosted to the west of the lake (according to the satellite data). As she can only be tracked for 6-8 hours every 3-5 days (at this time of year), it would be reasonable to assume she is using the site considerably more than depicted below.

County Mayo 19th November 2013 to 30th January 2014

19th November 2013 - The first fixes plotted in Co Mayo were near Foxford, roosting on a mountainside above Lough Roosky. She was here at 05.39 hrs and active before dawn.

Brief stop near Mallaraney19th November 2013 at 13.01 hrs, 53.4 km from the roost near Lough Roosky

The following transmission came in on the 21st November, roosting approximately 32 km to the north of Mallaraney, 8km south-east of Belmullet. She now has a distinctive home range composed of a selection of roosting sites and regularly revisited foraging areas. It seems that she is now settled and spatially aware of the surrounding landscape.

County Mayo, clumped fixes show key roost sites and foraging areas used between the 21st of November and 30th January 2014.

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