Wednesday 27 March 2013

Trill of the chase


As I was crossing Fen Causeway on my way home from the museum, I saw a group of birds sitting in a large willow on the south side of Coe Fen.  Even though I had no binoculars, I thought they looked like Waxwings.  They were sitting like Waxwings, acting like Waxwings, perhaps not as casual or disorganised as group of Starlings would be. As I walked up to the tree I could see they were not starling black, and when I heard them trilling I knew there was no doubt about what I was looking at.  They sat there preening, calling, and not caring about me, which is what Waxwings often do.  I have had a good Waxwing winter, with several encounters locally (the photo is of one of those, from January), but I expect this will be the last group of the spring for me.  I am glad winter might finally end, but I will miss the excitement of hearing trills and then skidding to a halt on my bike or making a mad dash inside for binoculars.

Monday 18 March 2013

Oil beetles


In a week of cold and rain, we timed our visit to Wallasea well and the sun was burning off the morning fog when we arrived.  We climbed up the sea wall and within five metres Rosie had found an oil beetle.  There were two more next to it, and as we looked about we realised we were surrounded.  The air was cold, but down at the base of the long grass the sun had heated things up and oil beetles were busy munching on the grass stems, looking for mates, and having a good time.

A large colony of Meloe proscarabaeus was discovered here in 2011.  Today we were visiting with Buglife to see how extensive the colony was, so we were delighted to find what Steven called 'oil beetle heaven'.  Oil beetles have an amazing lifestyle.  They lay eggs at the base of plants, the larvae hatch out and crawl up to the flowers where they wait to jump on to a visiting bee.  If the bee is of the right species, the larvae will be carried back to the nest where they will live off the bee's eggs or larvae and the provisions that the bee has left.  As well as this, oil beetles are big and bold and have a purple sheen.  Our two common species, proscarabaeus and violaceus have kinked, pointed antennae.  The male has a very pronounced kink.



The female has only slightly kinked antennae.  During courtship the male grasps the female's antennae with the crook in his, as you can see in John Walters' video of a pair mating.


Oil beetles are immediately appealing, but something I had not appreciated was a common leaf beetle, Phaedon timidulus.  This is an easy beetle to find on umbellifers, and there were several on the Cow Parsley at the top of the sea wall today.  I was surprised to discover recently that despite being one of our commonest Chrysomelids, Phaedon timidulus is an uncommon insect in the rest of the world; it is known only from Britain, Ireland, France, and Tunisia.  It is nice to find something that calls Britain home rather than a small outpost at the end of the main part of its range.


In the afternoon we checked another part of the sea walls.  The sun had gone in now, and I was not surprised that we found no more oil beetles.  But there were better things to come.


The genus Lixus has quite a history in Britain.  After some confusion, it seems that four species used to be found here, but they were all gone by 1960.  Then we got a new one.  Lixus scabricollis was discovered in an insalubrious part of Kent in 1987, and it has since been found in several coastal counties in southern England and Wales.  Nobody seems sure whether this represents a welcome natural return for Lixus or an accidental introduction.  It may be a bit of both: a colonist that has found its way here from introduced populations in northern Europe.  Either way, I was very pleased when one fell out of the first Sea Beet I shook in the hope of finding this banana-shaped weevil.



Like most weevils, it tucks its legs in and plays dead when it is disturbed.  It is long and thin and can easily pass for a seed when it does this, but it reminds me of a retriever lying by the fire with its head between its front paws.  We searched more Sea Beet to see how common the banana beet weevil was.  There were a few more, and, rather oddly, one beet plant produced Malvapion malvae, Aspidapion radiolus, and a dozen Podagrica fuscipes.  These three species feed on mallow, so perhaps there was a mallow nearby.  Podagrica fuscipes is much the scarcer of the two British species in this genus.  The other, Podagrica fuscicornis, is widespread in south-east England, but fuscipes is rare away from the Thames Estuary.  It was not an unexpected find here in its heartland, but it was still good to see it.


By late afternoon a Short-eared Owl was out hunting over the rough fields, and it was joined by a Barn Owl a little later.  A nice male Merlin and more Corn Buntings than I have ever seen before were other highlights of the day.

Sunday 17 March 2013

Weevilosaurus

It has not been the weather for going out, but I had a day with broad-nosed weevils at the museum on Friday.  These weevils have short snouts, which takes away some of the cuteness, but they make up for it in other ways.  I am particularly fond of the prehistoric looking Trachyphloeus.  They look like little dinosaurs, armoured with a mixture of scales and soil, and with strange paddle-shaped spines.  If they are not ancient reptiles, they might be miniature hippos, with fat bodies and broad, rounded noses.  Appearances aside, some of them are also unusual in not bothering with males.  Males of Trachyphloeus angustisetulus have been found in mountains in France and Spain, but not in Britain.  It has three sets of chromosomes and it lays unfertilised eggs that hatch out into new beetles that are clones of their mother.


Trachyphloeus scabricul uses the more traditional way of reproducing, with males and females getting together and doing what comes naturally.  This species has larger paddle-spines than angustisetulus and it is not so fat: more hedgehog than hippo.


Somebody once said to me that if insects were the size of dogs, any one of them would be the most amazing animal you had ever seen.  Too right.

Wednesday 6 March 2013

Silver streak

After a warm yesterday, we hoped for a few more moths this morning.  We trebled the number of species (up to six today), and had another one of my early spring favourites, Yellow Horned.  This is not one of the most colourful moths, but it often looks so crisp and precise, with a texture like roughened brass neatly etched with black lines.  If you are lucky, or if you annoy it, it reveals its orange-brown antennae, which are unexpected on a moth that looks as though it was designed in faded, yellowing monochrome.



This was a nice start, but it was eclipsed by the star of today's show, a Water Shrew in the ornamental pool outside the offices.  Nick the gardener came in to tell us he had seen one in the pond he was cleaning out.  We went out to look, and it was doing just what he said it had been doing when he saw it: it swam quickly out from under the moss at the base of the fountain, wriggling like tadpole as it moved into the thick weeds.  It was now hidden, but we could still track its movements from the bubbles it sent up.  Then it swam just as rapidly back to the fountain, but often coming up for air on the way.  It looked sleek and silver-grey under the water, but once it broke the surface it was obviously a shaggy-haired mammal.  It did this every few minutes, and on some of its sorties it swam right up to the edge of the pool below where we were standing.  It was moving quickly and twitching all the time; if there is one things shrews are not are very good at it is lounging around and relaxing.





It was still darting in and out from its mossy fountain when I left for the day and went down to the common for another memorable encounter with the Barn Owl before it got dark.  I had to wait later than in recent evenings, but it appeared at 1750 and tonight it came even closer than it had on previous days.  It stared at me with its dark, black, impenetrable eyes as it flew past and then swooped down into the long grass.  I was glad I was not a vole.

Tuesday 5 March 2013

Bright start

This morning started bright and with a frost, so there was not much in the trap that Rosie had put out last night.  But the not much included one of Britain's cuddliest moths, Oak Beauty.  The appeal of this species is probably greater because it appears at a time of year when there is little else flying, but it is a soft toy of an insect whatever the season.



The sun stayed out and by lunch time it felt like summer had come.  This was a good time to look for insects on trunks and fence posts that had become warm in the sun.  Ladybirds are such good things: strikingly patterned, and common enough to bring a bit of colour to every day.  The Pine Ladybirds Exochomus quadripustulatus seemed particularly bright and shiny today, and I liked the ripples from the rings in the fence post  behind this Seven-spot Coccinella septempunctata.



There were many Kleidocerys resedae, another common but attractive insect, and one that can be found throughout much of the year.  Next week we shall probably be back in winter again, but today was a good reminder that summer will come.  I hope it is not like last year's.



Monday 4 March 2013

Mossing about

A nice sunny morning, so I went poking around in some sedge tussocks.  Some Notiophilus were out and about, having warmed up enough to scuttle around.  A Melanimon tibiale was more sluggish as it made its way across the moss; when spring arrives, this will be one of the commonest beetles on the bare sand patches on the heath.


A couple of weeks ago I found the lacebug Physatocheila dumetorum in dead leaves on an oak.  This week's lacebug is much smaller and it lives among moss on the ground.  It is Acalypta parvula, a common species, but easily overlooked because it is tiny.  It shares its mossy habitat with Simplocaria semistriata, one of the cute pill beetles, another family of insects associated with mosses.  Like the other pill beetles, it can pull its legs into slots on the underside of its body and it can pull the ends of its legs into slots on its legs.  It works like a mini Transformer, turning itself into a smooth oval, like a pill.  I do not recommend it for headaches.