Monday, April 30, 2012

Water Hog-louse

Our small garden pond (the same one that's home to the newts mentioned in a previous post) is also home to a thriving water hog-louse (aka water slater) Asellus aquaticus population - and this is their breeding season. This is a mating pair and eventually the female will carry her fertilised eggs around with her under the front of her flattened body. These are crustaceans which exhibit a considerable level of maternal care of their offspring and when the eggs have hatched the female will continue to carry her young under her body, between the front two pairs of legs until they're old enough to fend for themselves. Water hog-lice aren't too fussy about water quality and so will thrive in small aquaria, where it's easy to watch their reproductive cycle. 

The brown pigmentation of their exoskeleton takes time to develop and in the youngsters it's transparent, which makes it easy to watch the workings of their internal organs under a microscope. This one is a juvenile that is only just beginning to develop the vestiges of pigmentation .....

..... and this one is a little further along the road to adulthood.

Asellus is an isopod crustacean, meaning that all of its legs are of similar length, unlike the amphipods that have a combination of long and short legs. 

Sunday, April 29, 2012

Blues That Lift the Spirits ...

I thought we might be too early for the spring gentians Gentiana verna when we visited Widdybank Fell in Teesdale on Friday - a rare day with some sunshine - but a few of these botanical jewels were just coming into flower in some of the more sheltered spots. At times the sky was almost as blue as the gentian petals, during a welcome break between days of heavy rain.

Sunday, April 22, 2012

Shortage of Bees

At the moment we've got pears, plums, apples, blackcurrants, gooseberries, white currants and red currants in flower....

..... but not many of these around to pollinate them. This one is on blackcurrant blossom. Back in March, in that warm spell, there were plenty of foraging queen bumblebees but the last two weeks of cold, wet weather have sent them back into hiding. Still,.........

.... there are a few tree wasps Dolichovespula sylvestris around to help out - this one is on a gooseberry flower - although they're not hairy enough to be very efficient pollinators. 

Doesn't look like it's going to be a bumper year in the fruit garden........

Friday, April 20, 2012

Some Nice Moves from our Garden Newts ....

We only recently realised that the small pond that I installed three years ago, which is only about one metre long, has been colonised by palmate newts, which are now resplendent in their courtship colours...... which are not so evident from this angle ....

.... but show up nicely when you can see the amphibian's flanks ........

...... and tail.

Tonight I spent a fascinating half-hour watching the whole courtship ritual. These two are patrolling the dead leaves on the bottom of the pond, through a blizzard of water fleas that will, in due course, provide plenty of food for the newt tadpoles.

There was a lot of chasing going on, over and under the leaves, and then ...

.... this one spotted a potential mate ....

.... and chose the brightest-coloured beech leaf in the pond as his dance floor, where he began to display some of his best moves ....

...... first positioning himself at right-angles to her and using his tail to waft water in her direction ....

...... then executing an acrobatic handstand and ninety degree turn ....

..... until he could waft the stream of water directly over her with his vibrating tail.

Then the batteries on the camera (a waterproof Pentax W20) ran out ....but he's probably still dazzling her with his dancing now, as darkness falls.

Wednesday, April 18, 2012

Mystery Miner

I found several of these mining bees feeding on dandelion flowers yesterday. I think that brush of hairs on the hind legs, used for collecting pollen and sweeping soil out of the nest tunnels, narrows it down to an Andrena species but I'm not sure which one it is .............any advice?

Monday, April 16, 2012

It's bad news when these appear in your garden. This is the spore-producing shoot of field horsetail Equisetum arvense, about to liberate thousands of spores which have a unique adaptation to aerial invasion, which you can see by clicking here.

Once it's established this plant is well-nigh impossible to eradicate. Its underground stems (known as 'devil's guts') run deep and fragment easily, regenerating new plants just when you think you've dig it all out. Still, it could be worse; back in the  Carboniferous, 300 million years ago, when the coal measures were laid down, these grew 10 metres tall. 

Saturday, April 14, 2012

Torpid Bees

It's so cold here at the moment that I'm beginning to worry that none of our fruit trees and fruit bushes - which are in full flower thanks to that exceptionally warm weather back in March - will be pollinated. There are very few bees about and those that are, like this one dangling from a gooseberry flower, are completely torpid and just waiting for the weather to warm up before they get back to work.

Still, it does make it easy to take macrophotos of them - this is with my 6 year-old little pocket point-and-shoot Pentax W20, which focusses down to 1cm., using the built-in flash. Amazing piece of kit - and it's waterproof....

Thursday, April 12, 2012

Shocking Pink

Today's Guardian Country Diary, which describes the impact of a sudden snowfall in Teesdale last week, also features the opening of the new season's cones on larch trees.

Image Source:

Lakeland poet William Wordsworth - he who "...wandered lonely as a cloud ..." and admired "...hosts, of golden daffodils..." - disliked larch trees intensely, considering that they disfigured his beloved Lake District landscape. Planting larch, for its fast-growing valuable timber, became very popular amongst landowners during his lifetime.

Wordsworth had nothing good to say about its foliage, complaining that "In spring the larch becomes green long before the native trees, and its green is so peculiar and vivid, that finding nothing to harmonise with it wherever it comes forth, a disagreeable speck is produced". He did rather grudgingly admit that he found its juvenile cones attractive, though, writing " must be acknowledged that the larch, till it has outgrown the size of a shrub, shows, when looked at singly, some elegance in form and appearance, especially in spring, decorated as it is then by the pink tassels of its blossoms". 

Wordsworth and the late, great forester Alan Mitchell (1922-1995) who was always equally forthright in his opinions, would never have established a meeting of minds if they had lived in the same era. Mitchell described larch as "...amongst the most valuable and decorative of all the trees we grow". He also drew attention to its value to our native wildlife: "Larches attract a variety of birds", he wrote, "crossbills feed on the seeds available to them from August while their staple diet of Scots pine seeds is not yet ready; tits feed in summer on caterpillars and aphids and in the winter on aphid eggs; redpolls, siskins and bullfinches nest in plantation trees, and buzzards and ravens in the spreading tops of big, old trees. The light, deciduous foliage allows the persistence or development of the pre-vernal herb layer so prized under oakwoods: bluebell, bugle,sanicle,wood-sorrel, and grasses, and their associated butterflies and other insects". (1)

On the tree, if not on its place in the Lakeland landscape, I tend to side with the pragmatic forester and naturalist rather than with the romantic poet ... but then, I rather like those shocking "pink tassels" and those bunches of new needles, like lime green shaving brushes ..... but maybe that's all to do with growing up in the 1960s, when psychedelic art was all the rage.... although, even then, I would never have chosen those colours for a shirt and tie combination.

1. Alan Mitchell. Alan Mitchell's Trees of Britain (1996) HarperCollins. ISBN 0 00 219972 6

Wednesday, April 11, 2012

The Benefits of being Hermaphrodite

It's seed-sowing time again - a time of hope and expectation, tempered only by the knowledge that the garden snail population is waking up too, ready to chew its way through all that tender new growth. Some time ago I devised a way of reducing the garden snail population by giving them somewhere to spend the winter where they could easily be found (click here) and then transported into the countryside. These two, caught in the act of mating, are a couple that I missed.

Garden snails Helix aspersa are hermaphrodite but nevertheless exchange sperm, as these two are doing. Being hermaphrodite is one of the secrets of their success because it means that every individual in the population can lay eggs and produce offspring; if animals exist as separate genders, either male or female, only half the population can lay eggs.

Click here to see some images of snail eggs and click here to see the baby snails that emerged from them.

Monday, April 9, 2012

News from the Nest

Back on March 23rd. I posted some pictures of a pair of collared doves that had built a nest just a few metres from our bedroom window.  Now they have two chicks - the one on the right in the picture above has its beak facing towards the viewer, the one on the left is facing away. In the 17 days since the original post there have been three events that could have resulted in disaster for the doves. First a grey squirrel visited the hawthorn tree but didn't find the nest and eggs. Then, a week ago, we had a whole day of heavy snow and high winds. Then today a sparrowhawk perched on the top of the tree and flushed the parent bird. She escaped safely and now she's back on the nest with her chicks. Meanwhile, the local sparrowhawk is still around. We'll be glad when the nestlings have fledged - this is all getting very tense!

(This picture of our local sparrowhawk was taken at the end of December - it's the female, presumably his mate, that shows up in the garden at the moment)

Friday, April 6, 2012

Here be Giants

This wonderful woven willow giant sits on the bank at the northern end of the Woodland Trust's Low Burnhall wood near Durham city.

His natural materials blend in beautifully with the surrounding hedgerows and grassland.....

...... and he's there to greet every walker that arrives at the site...

..... a friendly giant......

.... perched on the skyline, visible from a mile away as you climb up the hill from the south, resting his feet for a while ....

...... and spending his time admiring the view, surrounded by the sound of skylark song and the coconut scent of gorse flowers.

For pictures of the Low Burnhall Farm Wood in summer, click here

Monday, April 2, 2012

Forsythia Flattened by a Bacterium

I found this strangely flattened stem when I was pruning the Forsythia bush in our garden (see below for an example of a normal Forsythia shoot for comparison). It's suffering from fasciation - a sideways proliferation of the growing tip of the plant that results in a broad, flat stem. This was most probably caused by infection with the leafy gall bacterium called Rhodococcus fascians (formerly known as Corynebacterium fascians) which upsets the balance of hormones that control the plant's growth. 

Fasciation occurs in a wide range of plants and you can see some further examples by clicking here.

Sunday, April 1, 2012

Last Year's Des-Res...

We found this exquisite wren's nest in a blackthorn bush beside a drystone wall along the Pennine Way near Middleton-in-Teesdale last week. It's last year's nest and over the winter the moss cladding that the bird carefully wove into its structure has continued to grow, producing a living green dome. The entrance hole on the side looks like it has been used, maybe by a field mouse during the winter.