25th June 2009

It was back to Oldshoremore today, before meeting a crofter over in Scourie late afternoon.  The dunes were alive with butterflies today, with many Meadow Brown (larger and darker than our ones around Stirling), Common Blue, dashing Dark Green Fritillaries as well as a couple of Large Heaths.  A Golden-ringed Dragonfly also put in a couple of appearances.

 

There was an abundance of Bush Vetch in the dunes, but what was also encouraging was that the area supporting suitable flowers for Great Yellow Bumblebee extended well back from the dunes, almost to the road, where the vegetation suddenly switched to that more typical of acid grasslands.  Another queen Moss Carder Bee was caught some distance from the dunes - the net in the photo marks the spot - and there were phenomenal numbers of the elegant Globeflower.  I was clear that the long-tongued Garden Bumblebees were concentrating on the Kidney Vetch, with the White-tailed Bumblebees largely on White Clover and Bird's-foot Trefoil, the latter (as well as Bush Vetch) being used by Common Carder Bees.  I was surprised to see a Heath Bumblebee queen nectaring at Milkwort, though others were at White Clover and Bird's-foot Trefoil.  It would seem that Bird's-foot Trefoil is not used in relation to its abundance; perhaps as more worker bumblebees emerge, this situation may chance.  Workers were very scarce at Oldshoremore, though one tiny worker Garden Bumblebee was at Kidney Vetch, dwarfed by the larger queens, and a worker Common Carder Bee was at Bush Vetch.  As it happened, the Honey Bee was the commonest bee in the area, and a crofter I met mentioned that he may have seen a Great Yellow Bumblebee.

 

After five hours, I was back in the dunes and as walked slowly along, heard a deep buzzing a few metres off to my right.  It was intermittent, suggesting a feeding bumblebee, and I carefully made my ways around tall clumps of Marram.  I reached the clump, behind which the bee was clearly active, and waited.  Before too long, a large golden bee hove into view, but it was moving away, quickly out of net range. I could see the black band across the thorax - it was a Great Yellow Bumblebee!  She moved off, returned and cruised by a short distance away, and then she was away.  Caithness 4: Sutherland 1!  She had presumably been feeding at the Bush Vetch there.  I was somewhat relieved, as I had been concerned that, even with this seeming to be an early spring, it was still early for the queens of this late-emerging species.  Also, we did not know how numbers of Great Yellow Bumblebee had fared since observations in 2006, when two queens were seen in early July.