Little Assynt – a visit in late spring
On 24th March we had an early spring walk along the All Abilities Path at Little Assynt (see Signs of Spring on Little Assynt). A variety of circumstances, including bouts of Covid and subsequent visits to friends and family down south, prevented us getting back there for all of eight weeks.
However, on 21st May, after the Bird Race, we spent the afternoon walking the Loch an t-Sabhail or Loop Path from east to west. The outing was intended to be purely recreational, but, as always, we found ourselves recording features of interest.
Woodland relicts
On the left, not far along the path, there is a veteran downy birch sheltering a large patch of bluebells (photo 1; NC155252). This popular member of the lily family is considered further south to be a good indicator of ‘ancient woodland’ sites. In Assynt it also occurs under bracken and occasionally amongst heather, albeit in areas that may once have been wooded.
The former extent of native woodland on Little Assynt has been somewhat obscured by the late 20th century plantings we inherited, so such indicator species are well worth noting. A little further along the path, the bluebells were joined by the starry white flowers of greater stitchwort, the yellow ones of primrose, and by the fruiting heads of wood anemone.
All are associated with present or former woodland cover, on well-drained fertile soils clothing slopes above and below the paths, possibly on small areas of glacial till. These areas, round the edge of outcrops, were for practical reasons often followed when the paths laid out.
Less shaded grassland communities in these areas were sprinkled with the small white umbels of pignut, whose tasty tubers had been targeted by badgers, leaving typically untidy snuffle-holes.
Molehills are another indication of the fertility of the soil found in such places, but holes giving access to their extensive burrow systems are normally well concealed. We were, therefore, surprised to come across an obvious example at the base of a planted Scots pine (photo 2). We later noted several more in places beside the path, together with conventional molehills. Moles do emerge from their burrows at times, hence remains found in bird of prey pellets, but we do not know why.
Boggy areas
In contrast to the occupants of these well-drained fertile soils are those of the wet heath and bog communities which occupy extensive low-lying areas on deep peat elsewhere on the estate. Although less species-rich, they are no less important since they have a capacity for carbon sequestration and retention that can exceed that of mature broad-leaved woodland.
A feature of these communities in 2023 has been the conspicuous fruiting of hare’s-tail cottongrass (photo 3). It can occur in dense stands, probably where the underlying peat has never been dug for fuel. On Little Assynt, however, as elsewhere in the parish, it is often patchy and the surface of the ground is broken, evidence of the localised drainage of boggy areas and their exploitation over many centuries. The vegetation is slowly recovering, but it will take a long time.
Pathside plantings
Alders were a frequent component of the broad-leaved planting mix on Little Assynt, as in crofter forestry schemes elsewhere in the parish. The species account in the Flora of Assynt (p. 81) describes them as growing ‘occasionally on the edges of burns and lochs, flourishing on islands in the latter, where …free from grazing’, so there has been a major change in their status locally.
They certainly thrive and, where paths pass close by (photo 4), their branches, covered with shiny spoon-shaped leaves, have sometimes required drastic pruning. The vigorous regrowth is often a good place to look for insect life, whether herbivorous, predatory or parasitic.
The difficulties of insect identification
We were rewarded on this occasion by finding (at NC154262) one of the largest British sawflies Trichiosoma sp , with a dark body nearly 20mm long and clubbed antennae (photo 5).
We thought that such a conspicuous insect, whose larvae feed on the leaves of alder and other trees, would be relatively easy to name. However, a specialist work on this group of hymenopterans states that ’separation of the species is …difficult, and considerable confusion still exists over the taxonomic status of some [of the 20+] Trichiosoma species’. Admire and pass on!
A second insect noted nearby (photo 6) was strikingly marked in black and yellow, but belonged to an even more challenging group of hymenopterans, the parasitic wasps (suborder Apocrita), of which approximately 6,600 species have so far been listed for the British Isles. Narrowing it down to the family Ichneumonidae (Darwin wasps) still gives a choice of some 2,586 species. It is possibly a member of the type genus Ichneumon, but that is as near as we shall get. These insects provided a salutary reminder of the biodiversity out there, and the limitations of our knowledge of it (as of all but a handful of British entomologists).
The shelter and its occupants
A little later we took a short break beside the heather-thatched shelter on the south side of Loch an t-Sabhail (photo 7, NC152264), admiring one of the earliest of the dragonfly clan to appear each spring, a large red damselfly Pyrrhosoma nymphula.
Exploring the rather dark interior of the shelter, we found the floor white-splashed beneath a supporting beam, with tawny owl pellets scattered about (photo 8). No self-respecting naturalist can resist the challenge of checking these out, so a whole pellet and fragments of another three or four were collected for later investigation.
We struck gold, since teasing apart the matted fur and bones in the pellets revealed the remains of seven small mammals. The bulk was contributed by three field voles, favourite prey species of both tawny and barn owls in such rural landscapes, and readily identified by their sharp-edged molar teeth.
However, there were also the cranium and lower jaws of a single bank vole, with much more rounded molars. This would appear to be first evidence of the presence of this species on Little Assynt, although three were trapped inside buildings at Loch Assynt Lodge, not far away, in 2001.
Also present were the tiny lower jaws, with their red-tipped insect-crunching teeth, of two common shrews and one pygmy shrew, separable by their size.
Back to the start
We then continued back along the path to the Tree Nursery carpark where we had started, noting the conspicuous flowers of a further woodland relict species, wild strawberry, beside the path (NC148255, photo 9). We also added stonechat and willow warbler to the sparse bird list for the afternoon, together with that of several cuckoos heard.
Our leisurely perambulation had taken three hours, and provided us with, as usual, an unpredictable range of delights.
Ian M. Evans and Gwen Richards
All photos by Gwen Richards