Spring Advances

There have been a lot of consequences of the current coronavirus outbreak that we might not have foreseen. One of these at Blashford are problems for our breeding common terns. The virus and consequent cancellation of all volunteer work parties has meant that the rafts the terns usually nest on cannot be launched. Luckily the very large raft we put out last summer on Ibsley Water was never brought in and the terns seem to be willing to consider it as a nest site.

two tern pairs

Displaying common terns on the “Mega raft”.

The bird to the right has a fish, this will be a male that has caught a fish to bring back to his mate as part of courtship feeding. This behaviour will show a new partner his fishing ability, or just strengthen existing pair bonds, it will also help the female gain condition in readiness for producing the eggs, a huge drain in her resources.

It will be interesting to see how many pairs turn up this year, after years of steady growth the population has fallen in the last couple of years, I think due to poor weather at migration time and more problems competing with nesting black-headed gulls. We also seem to have had very few birds passing through, until this year that is. The other day 68 were counted over Ibsley Water, of course that does not mean they will stay to breed and most have certainly moved on, but at least 14 remain, so perhaps we have a core of seven pairs to build on.

The spring is peak time for birds passing through and as well as common tern we usually see some of their more northern nesting cousins, Arctic terns and occasionally a few of the inland marsh nesting, black tern, although sadly they do not nest in the UK. Black tern and another passage visitor the little gull are probably on their way to nesting around the Baltic Sea area. This spring does seem to have been a good one for little gull, with birds being seen on several days.

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Little gull, one hatched last year (2cy).

The young birds, hatched last year vary a lot in the amount of dark markings in their wings, this one being fairly typical, but some have almost totally black upper-wings and some much reduced. These birds used to be called “First summer” , although this might seem a little odd as they were hatched last spring, but their actual first summer would have been spent in juvenile plumage, so “First summer” actually described the plumage, not the age of the bird. Things get more confusing with some other species that time their moult differently, so these days you are more likely to hear birders referring to “Second calendar year” (often reduced to 2cy) indicating the age of the bird, rather than the plumage.

As it is spring most of our birds are settling down to nest. As I was having some lunch on Monday a mallard was on the new pond built last year behind the Education Centre, I wondered why it was so reluctant to leave as I sat down nearby. The answer was actually obvious, it had a nest near the pond and when I looked away it flew a short distance into the vegetation and disappeared, no doubt it was just taking a short break from the arduous task of incubation, which is all done by the female.

mallard duck on Centre pond

mallard duck on Centre pond

Blashford Lakes is not an obviously good site for orchids, generally when thinking of these the mind goes to long established chalk downland and these are certainly very good for orchids. However just because Blashford is a recently developed old gravel pit complex this does not mean there are no orchids. In fact we have at least seven species, which might seem surprising, but the secret is that the soils are very nutrient poor, something they have in common with old chalk downland. Our commonest species is probably bee orchid, with scattered groups in various, mostly grassy, places. Next would be southern marsh and common spotted orchids in the damper areas. In deep shade and so probably often overlooked there are common twayblade. On the dry grassland was have a growing population of autumn lady’s tresses and, since it was first found last year a single green-winged orchid. Last years plant was a good tall one, but it got eaten, probably by deer or rabbit. I wondered if it had come up this year so went to have a look yesterday and found it, although a good bit smaller than it was last year, but still flowering.

green-winged orchid

green-winged orchid