Our studies of UV’s movements, both last season and again this year, are providing some good data on how male ospreys in this part of their life-cycle (“pre-nuptial phase” in the slightly coy technical jargon) can cover very large amounts of ground in a relatively short time. During these excursions, they will be collecting information about hunting opportunities in different types of terrain, and perhaps finding out how many other ospreys are present (or absent) in a given area. This modifies the conventional view that males stick solely to their natal area which, we are beginning to understand, is not a new “home” at this stage – but rather a base of operations from which these longer-range forays can be made into the surrounding region. Yesterday’s activity was a very typical example.
UV had a busy day, travelling 185 km mostly along two Scottish rivers – the Border Esk and the Annan. Last year UV explored some of the Esk but not the Annan.
You can see his course was mazy. Initially he flew across the fells from Liddel Water to join the Esk at Langholm, which he visited last year.
Sometimes he was about 400m above the terrain deciding which way to head next but for the most part he followed the course of the rivers. He wasn’t travelling particularly quickly bar a few 90 kph bursts, usually downwind, to get to the next interesting looking place!
One such was Black Esk Reservoir which he encountered for the first time yesterday.
UV slowed down as he travelled up the west side of the reservoir but headed away after that short recce.
Over the next 30 mins he crossed agricultural land to reach the Annan and changed course to follow it to the coast. He made an occasional detour – one of note was to Kirk Loch and Castle Loch at Lochmaben.
UV went back to follow the Annan southwards. He had two brief stops beside the river, no fishing involved, before he reached the estuary. A bleak looking spot when this photograph was taken!
Compared to 2016 UV’s migration this year was much more direct and more miles were covered on average each day. He went straight to active nests at Kielder and established there were no vacancies. At the end of summer 2016 UV spent many days in an area where it appeared he could try and form a territory this year, but he has hardly flown over there. Instead he is visiting old and new river systems. If on his travels he found a nest with a lone female would he stop and court her? Perhaps. But he is not quite 3 years old, official birthday 4 June, so still young to breed.