Wednesday, April 1, 2020

Local patch lockdown 1: bird watching

We've been confined close  to home for nearly two weeks now, and with the Coronavirus lockdown in place we only leave home very early in the morning, when no one is around, for the regulation exercise walk. At that time of day we see very few people and we all pass one another at a safe distance, with just a cheery greeting.

We are fortunate because there is a network of footpaths and lanes on the edge of our little market town, that start just a couple of hundred yards from our front door.

Some of the lanes like this one, known locally as the Mile Lonnen, have old hedgerows and trees but large areas of land here were opencast coal mined about 25 years ago, and have slowly been recovering. When the mining finished they restored field boundaries with miles of new hedges and dry stone walls and planted shelter belts of trees that are now well developed and form wildlife corridors. They also left a large pond.

Walking the same route every morning has a great deal to recommend it, because you soon get to notice small changes, especially at this time of year when spring is gathering pace.  

One of the delights has been the realisation that there is so much bird life in these edgelands, close to home. So here is a photographic record of sightings in the first week of lockdown.

Blue tit in a larch plantation

Bullfinch feeding on cherry plum flower buds

Soaring buzzards, above a conifer plantation that is a probably their nest site


Curlews, that feed in the fields here on their way to nest sites on fellsides in Weardale


Great tit


House sparrow

Tree sparrow

Some fine aerial displays by lapwings

Robin in full song

Skylarks making song flights soon after sunrise

Song thrush

More willow warblers arriving every day

Counted six pairs of  yellowhammers. The combination of hedges, broad road verges and pastures suits them well

Numerous dunnocks, aka hedge sparrows

Rooks feeding on leatherjackets (cranefly larvae) in the pastures 

Jackdaws on a farmhouse chimney pot

Also seen but not photographed: sparrowhawk, magpie,carrion crow, starlings, coal tit

Wednesday, March 18, 2020

Lapwing courtship and rivalry

You know that spring has really sprung when you witness this kind of bird behaviour.

There were three lapwings in this oilseed rape field - a female (left) and two males. The male in the right foreground had just finished a brief courtship flight display, then pursued the female through the plants on foot, until they both stopped. Then he turned and started pecking at the ground, in a perfunctory display of making a nest scrape, and displayed his rump. The second male, in the background here, had similar ideas. A recipe for trouble.

They both got airborne, to settle their rivalry with some aerial jousting. 

What followed was a lively display of close-quarters intimidation and some spectacular aerobatics, with a lot of noisy calls but no actual physical contact.

No idea how they judged who was the victor and who was the vanquished but .....

.... only one of them had the privilege of mating.

Saturday, March 14, 2020

The hidden life in knapweed seed heads

Recently I wrote a piece for the Guardian Country Diary about the insects that live and breed in knapweed seed heads. During the summer bees, butterflies and many other insects visit the flowers for pollen and nectar, but some flies and small wasps also visit to lay eggs in the seed heads.

One of the common names for knapweed is hardheads, and if you squeeze the seed heads you find that some are harder than others, as though they have a small nut inside. These are galled by a tiny tephritid fly called Chaetostomella cylindrica , whose larvae feed on the seeds as they grow

This is a seed head cut open, in March, to reveal the barrel-shaped white larvae, inside their gall. By this stage most of the seeds have been eaten. Goldfinches visit knapweed to eat the seeds in autumn, so some of these larvae may be eaten by them too, though it seems unlikely that the birds can open such a tough, woody gall.

But the tephritids have other enemies.

                   This is the adult, rather beautiful fly, Chaetostomella cylindrica, with iridescent eyes and smokey bands across its wings.

It's easy to collect these, from seed heads enclosed in a jam jar in late winter. The hole in the lid allows the flies, which naturally climb, to enter the plastic collecting tube on top, where they can be removed. They climb more reddily if the lower jar is enclosed in a dark paper sleeve, which encourages them to climb towards the light.

There are some surprises amongst the emerging insects.

These are chalcid wasps, which are parasites on the tephritid fly larvae. So far, two species have appeared - this, one, with the brown abdominal bands .... 

....... and this exquisite little metallic green species. I think this one is a male ......

..... and this one, with the elongated, pointed abdomen, is the female. All have spent the winter feeding on their tephritid larval hosts during the winter.

Many other species in the daisy family, like thistles and burdock, have large seed heads that persist through winter and host a variety of small insects.