Picture: Reed Warbler

From The Independent:

Tot it up. Buds are bursting. Leaves are opening. Blossom is blooming. Flowers are flourishing. Butterflies are emerging. Trout are rising. Birds are singing. Birds are nesting. And indeed, birds are arriving. The arrival of the migrant birds that winter in Africa and spend the summer breeding in Britain is perhaps the most exhilarating April event of all… it has been estimated that (before the declines began) as many as four million willow warblers alone landed in Britain every spring – four million pairs of tiny whirring wings crossing the Sahara, the Mediterranean, Spain and France and finally the Channel before fanning out across the land to begin their silvery descending songs.

For Fleet Pond specifically, we have had as many as 40 breeding pairs of Reed Warbler in the reedbeds. This bird is the one the cuckoos need at the pond because they are the cuckoos’ favourite for nests.  They can watch the birds building nests in the reeds from the trees and then drop in and lay as soon as a few eggs have been laid (see picture below).

Picture: Reed Warbler Raising the Young of A Common Cuckoo

Also keep an eye out for house martins and swifts.  Nothing says spring more than a flock of swifts screaming their welcomes overhead.

Picture: Swift in Flight

Picture credits: here, here and here.

Peter Martin writes:

Although a few may have been seen during April, May is the month when there are often lots of Orange Tips flying around Fleet Pond. The footpath from Avondale Road alongside the Brookly Stream is often a good place to see them (see map on About page above). Like a large number of insects and animals, nature seems to make the male of the species more colourful and this is particularly true of the Orange Tip.

It is the male that has the splashes of orange on the upperside tips of the forewings. The female upperside is just white, apart from a black edging on the tips of the forewings. Underside hindwings of both sexes are a mottled green in colour. As females have no orange, they may be mistaken for Small Whites, or Green-veined Whites.

In some years, a few of the Orange Tip butterflies may be miniature – about half their normal size. The orange, lenticular-shaped eggs that are laid at the base of flower stalks on Cuckooflower or Garlic Mustard are unmistakable. As they are not much bigger than pin-heads, however, you may need a focus scope to really get a good view of them.

Before emergence, the colour of the eggs tends to pale and when the tiny caterpillars appear they may eat their eggshells, before turning their attention to the plants’ seed pods. As they grow, they may also eat the flowers and leaves and, as they are cannibalistic, even other caterpillars. After about 25 days, they pupate and, with their green hue and strange shape, the chrysalides closely resemble the seed pods of their food plants.

Orange Tips remain in the pupal cases until the following spring, when they emerge over a period of several weeks. It always seems a shame that such beautiful butterflies spend most of the year as egg, caterpillar and chrysalid, but each only flies for about 18 days. The first one recorded in my Fleet garden this year was a male seen on 19th April. If you have Honesty growing in your garden, the Orange Tip may lay its eggs on this plant.

To find out what butterfly will be featured next month, take a look at this blog in early June!

Peter Martin acted as author for a booklet entitled “Blackwater Valley Butterflies” which contains photographs of all 32 species found in this area together with information about their life cycles. Copies are available for £2.50 plus £1.00 p.p. from Blackwater Valley Countryside Partnership, Ash Lock Cottage, Government Road, Aldershot, Hants, GU11 2PS. (Cheques should be made payable to B.V.C.P.).

Picture credit here.