Woodpecker sightings increase.. chilly month keeps insect numbers down – where are all the butterflies?.. a strange season for herbaceous plants.
Temperatures on Wildwatch Wednesdays remained consistently below 10C, although it was sunny on the 13th and 20th.
Great Spotted Woodpeckers, usually an occasional visitor to St Nicks, were seen on the 6th, 13th and 20th.. both male and female birds, and drumming was heard on the 13th & 20th. Could we see breeding on the reserve? But they were not seen or heard on the 27th.
Another scarce, but increasingly recorded bird, is Goldcrest. This species was heard or seen on the 6th, 13th and 27th. The evergreen trees near the Environment Centre are a good place to look for these birds.
Our regular summer visitors are being seen in good numbers. Up to ten Chiffchaffs were seen and heard on the 6th, with at least five on all the other Wildwatch Wednesdays. Blackcaps, too, are well-established, with at least eight singing males, and accompanying brown-capped females also seen. One summer visitor which was regularly seen a few years ago, but has hardly been recorded in the past three years, is Willow Warbler. Last year, just one was heard but not seen. But on the 6th, one was both heard and seen along Osbaldwick Beck.
Our resident breeding birds are now setting up breeding territories.. Robin, Blue, Great and Long-tailed Tits, Dunnocks, Wrens, Blackbirds.. are all very vocal, and what lovely bird song we are hearing at St Nicks! But Goldfinches seem to be scarce at present.
Overhead a Sparrowhawk flew over the Dragon Stones on the 6th, and both Greylag and Canada Geese were recorded on the 13th.
On the 20th, we experimented again with half-hour “sits”, splitting into three groups, sitting in one place and recording what each group saw. In total, this amounted to 17 bird species, out of the 23 that we saw all morning. This is an exercise which we are intending to repeat.
April last year was chilly and insect life was slow to start, but this year was chillier still and many fewer insects were logged during the month. By the end of April last year we had seen nine species of butterfly. This year only seven butterfly species appeared, from mid-month onwards, and in very small numbers. Speckled Wood was seen only once; Brimstone and Orange Tip twice; Peacocks and Commas were few and far between, with Small Whites and Small Tortoiseshells only a little more frequent.
Equally, hoverflies were slow to appear with only four species logged compared with last April’s nine. The Drone Fly Eristalis pertinax was easily the most frequent, with only single sightings of Syrphus ribesii, Melanostoma scalare and Helophilus pendulus.
Hoverflies are part of the large order of 2-winged flies Diptera. Over 7,000 diptera species have been recorded in Britain and Ireland, so it is often quite difficult to identify to species the various flies we see around the reserve. With patience it can be done, and this month as well as the obvious and well-named Bluebottles Calliphora sp. we have seen several Phaonia subventa – with striped thorax and orange abdomen (the Phaonia family has 46 species of attractively marked flies, most preferring woodland sites). Also seen were a few Melinda gentilis blowflies.
The Dark-edged Bee-fly Bombylius major, with its startlingly long proboscis, is by far the commonest of Britain’s 9 species of Bee-fly and several were seen in April. They roam grassy places on the reserve and drop their eggs into the deep nest-cavities of ground-nesting mining bees Andrena sp. The bee-fly’s larvae parasitize the larvae of the mining bees.
Queen Bumble bees of various species have been seen throughout April, prospecting for nesting-sites and feeding on pollen and nectar to build up their strength for egg laying. Those positively identified were Buff-tailed Bombus terrestris, Red-tailed B. lapidarius, Tree Bumble Bee B. hypnorum and Common Carder Bee B. pascuorum. No doubt there were other species, but queen bumble bees fly rather quickly and erratically, making it difficult to focus on their markings with eye or camera.
Other invertebrates have included Gorse Shieldbugs Piezodorus lituratus on the gorse bushes all through the month, and at the end of the month a single adult Pied Shieldbug Tritomegas bicolor was seen on a woodland path. The only ladybirds seen during the month were the common 7-Spot in good numbers around the reserve. The invasive Harlequin Ladybirds were not seen in April, which makes a change. On the Environment Centre pond Whirligig Beetles Gyrinus sp. and Pondskaters Gerris lacustris began increasingly to be seen during the month.
As the Alder and Hazel catkins dropped, the remaining member of their family, Silver Birch, came into flower, the male catkins opening alongside the first leaves. Ash flowers, strikingly beautiful but easy to overlook, were out from the beginning of April along with much more conspicuous Sycamore. We don’t know how we managed to miss another member of the Maple family with even more showy flowers – possibly Norwegian Maple though we need to see the leaves and seeds to be sure. Hawthorn, Apple and Bird Cherry came into flower alongside the fading Blackthorn, promising a good show of blossom in early May.
It continues to be a strange season for herbaceous plants in particular. Although a number of species came into flower very early, the cold spring enabled them to last longer. The last of the Snowdrops hung on into the first week of April; everything else we recorded in February and March could still be found on 20th April. We were pleased to find that Sweet Violets on either side of Osbaldwick Beck had survived, and equally pleased if a bit puzzled by an apparently well established group of plants along the Bund path.
Herb Robert as usual was the first of the Cranesbills to come into flower. A single Shining Cranesbill appeared in the Centre garden, but so far there has been no sign of the plants along the Story Circle path. Fritillaries are notoriously chancy plants to establish, but bulbs planted three years ago have flowered again this year in a number of places. Unfortunately their slender and rather brittle stems are susceptible to damage so the chances of them seeding themselves are not high. Cow parsley, Green Alkanet, Forget-me-not sp. and Ribwort Plantain emerged a bit tentatively in a number of locations but their main show is still to come. Ivy-leaved and Common Field Speedwell came into flower mid-month, and the first fertile Horsetail shoots emerged right at the end.
In contrast to Red and White Dead-nettle which flowered all winter and are now in “You ain’t seen nothing yet” mode, closely related Yellow Archangel opened in April and will probably be over before the end of May. Unfortunately the St Nicks plants with their slightly variegated leaves are a somewhat invasive introduced form rather than the native variety, and their days on the reserve may well be numbered. Likewise most of the Bluebells are the introduced Spanish form or hybrids. The Reserve Manager would love to eradicate them and replace them with English Bluebells, but the difficulty of complete removal and the likelihood of re-hybridisation from local gardens make it a fairly low priority. Finally there is still time to see a fine display of Cowslips at the end of the meadow, and recently planted Primroses seem to have settled in.
Grey Squirrels were recorded on all four Wildwatch Wednesdays, Rabbits on three of the days, and Brown Rats also on three of the days – always in Osbaldwick Beck.
All photos were taken at St Nicks in April 2016