The Blues

The last few days have seen warm sunshine by day but chilly nights, meaning it has been poor for moths but good for day-flying insects. Today at Blashford Lakes I saw my first scarce chaser and downy emerald of the year and there were other dragonflies about too with reports of emperor, broad-bodied chaser and hairy dragonfly.

Most of the butterflies that over winter by hibernation as adults are getting scarce now and spring species such as orange-tip are dropping in numbers. there are a few whites around with all three of the common species, but the highlight today was the emergence of  blues. The small meadow near Ivy North hide had six or more male common blue as I went to lock up and at least three brown argus as well, the argus is brown, but an honorary “blue” all the same..

common blue (male), freshly emerged.

The brown argus look very like small female common blue, and the male common blues will get up to chase one if it flies by, however they quickly realise their mistake and give up. The first emergences are all males and the females will follow in a day or so. The reason for this is the same as that for male migrant bird arriving just ahead of the females. Evolution will push the males to be in place and ready for the first females to arrive, it does not pay to be late, so the pressure for males to be early is greater than that on females, who can afford to wait until they know there will be males to mate with.

The spring solitary bees are starting to disappear now, many species collect pollen from just a few plants and as these cease to flower they need to wrap up their breeding cycle. I did come across one interesting species today though, it was one of the nomad bees and the smallest species of them to be found in Britain, Nomada sheppardana.

Nomada sheppardana on forget-me-not

Visiting flowers is something many insects have to do to feed, it may sound an unproblematic things to do, the flowers want to offer a nectar reward, or perhaps bribe might be a better description, to the insects that will pollinate them. However it is not as safe as it might sound, flowers can hide predators, especially the camouflaged crab spider which match their colour to the flowers they sit on.

crab spider with hoverfly prey

The crab spider here matched the hawthorn flowers so well that I missed it and initially set up to take a picture of the hoverfly, only then did I see the spider!

It has not been a good year for ground-nesting birds so far this spring, with most lapwing and little ringed plover losing their eggs to predators. I suspect mammals at night as the ones nesting on the islands are doing much better. Or at least they were, on Thursday might all the black-headed gull on Long Spit abandoned their nests. Although I don’t know for sure I suspect that something swam out there and ate their eggs, probably a fox or a badger. These mammals are usually not that keen on swimming, but if they are hungry they will go to great lengths to get the food they want, I think small mammals, which are their preferred prey, are in short supply this year, which might be why they are seeking birds eggs more actively.

Despite a bad time for some ground-nesters the pair of oystercatcher are still doing well, with their two chicks growing well. They hatched on Long Spit, moved off to the shore near Tern hide and have now returned to Long Spit, this meant they were not out there on the night of the predator raid. So far the main gull colony on Gull Island shows no sign of being attacked and neither do the tern rafts on Ivy Lake.

 

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Dumping and Cutting, a Tale from the Roadside

There seems to be a lot going on at present. At Blashford we are resurfacing a lot of the paths, the entrance track and a few other improvements will follow.

We have also been putting out the tern rafts, so far the gulls have been taking most of the space but hopefully the terns will get their act together soon.

Out on Ibsley Water the lapwing have not been doing well, with most nests failing at the eggs stage, I suspect fox or badger, as the birds nesting on the islands seem unaffected.

I was at Fishlake briefly today and saw my first hairy dragonfly of the year, it was beautifully perched, but I did not have a camera with me!

Meanwhile back at Blashford we received an overnight donation of two large tractor tyres, several car tyres and the remains of a trailer. Not the kind of donation we want as it will cost a fair bit to dispose of. Fly tipping in the countryside is an increasing problem as the cost legitimate disposal increases.

Another increasing roadside problem is the decline in the the diversity of flora found on verges. I remember a series called “Wayside and Woodland” books, I always took the implication of the title was that much of the wildlife featured was to be found on waysides, that is path and road verges. The reason is the accumulation of nutrients, in fact this is probably one of the greatest threats to wildlife diversity in almost all habitats. It is no accident that habitats that are very poor in freely available nutrients are rich in species, they have to fight it out for resources and tiny differences in adaptations mean that one species will win over if even a very small change in the environment happens. Thus a thin chalk soil can produce an incredibly rich sward with huge species diversity. Where nutrients are easy to come by a few very vigorous specie swill overwhelm the competition and species diversity is low and growth vigorous.

Road verges suffer the twin threats of car exhausts, which are rich in nitrogen a key nutrient for vigorous plant growth. This growth then gets cut, often many times a year and the cutting left as a “mulch” further aiding the building up of nutrients. Cutting once  later in the year and removing the cuttings would reduce the nutrients, reduce the vigour of the growth and promote plant diversity. In fact Plantlife have just produced an excellent guide to managing road verges The Good Verge Guide

The Highways Agency also produced quiet good guidelines for highways managers, but these do not seem to have been widely taken up by the people that set the contracts for the work. A case in point is a very fine round about close to my home, this morning I admired the good show of ox-eye daisy and could make out the soon to be flowering stems of corky-fruited water dropwort as I waited at the traffic lights. On my way home tonight I see it has been mown and the cuttings left as a deep green mulch, it is large round about and easy to see across so there is little need for cutting for safety reasons. Slowly but surely this fine area of herb-rich, semi-natural grassland is being destroyed by the state, an act of causal degradation of our biodiversity in the midst of an extinction crisis.

I will end with a couple more moths form yesterday, the catch was small but included perhaps the smartest pebble prominent I have ever seen.

pebble prominent

There were also three very fresh poplar hawk.

poplar hawk

Out and About in the Sunshine

It has been very, very dry recently and reasonably sunny, however it has also been quite cold for a lot of the time, with north or north-east winds. This has made for quite a good spring for insects, certainly better than for several years, although it could do with warming up a bit and we will need some rain, not too much, just enough to keep the vegetation green. Yesterday it was warmer and the wind swung round to a more southerly direction.

I finally saw my second dragonfly of the year, I have seen lots of damselflies but dragons have been in very short supply. Although the view was brief I think it was a hairy dragonfly. I also found several of one of my favourite insects, groundhoppers, small relations to grasshoppers that get easily overlooked as they are adult in spring. There are three species in Britain and we get two of them at Blashford, or at least sop far I have only found two species. They favour damp, bare ground and can both fly and swim! The one below is a slender groundhopper.

Slender groundhopper

I was out bird surveying at the start of the day at Linwood reserve and noticed that the leaves on the oak there are mostly brown, almost all the first flush of leaves dead. Linwood lies in the valley of the Dockens Water a well known frost-hollow, these leaves had all been killed by the late frost that also had my early potatoes. This will be bad news for the nesting blue tit on the reserve as they mainly feed their chicks on winter moth caterpillars and these eat the first flush of oak leaves.

Hawthorn, or may, traditionally flowers in May, although often it seems to be earlier, this year it has lived up to the name and was in full bloom in the first week of the month. Although it has lots of flowers they do not seem to attract as many insects as the earlier blackthorn flowers, however one in a good sunny spot can still be worth checking for bees, hoverflies and beetles. I spotted this leaf beetle nectaring on the bush close to Ivy South hide as I locked up yesterday afternoon.

leaf beetle on hawthorn

Yesterday’s birds included a male wheatear on the Lichen Heath and the long-staying Bonaparte’s gull on Ibsley Water.