Sunday 18 September 2011

Asterisk the gall

After yesterday's thunderstorms and hail stones*, the sun returned today, so the Tense Towers Team headed off to Little Linford Wood, for some fresh air and exercice.

(*My posts nearly always start with the weather. Am I just pandering to the stereotype of the meteorologically-crazed Brit or am I a bit obsessive, do you think?)

At this time of year, the galls on wild roses are particularly spectacular. Colloquially, these are known as Robin's Pincushions*. Once back home and leafing through Bugs Britannica, by Peter Marren and Richard Mabey, I discovered that the natural and folk history of these galls is just as interesting as their colour and form.

The galls are caused by the Bedeguar Gall Wasp, Diplolepus rosae, and can contain up to 50 grubs, each in a separate chamber. Bizarrely, the grubs are infected by a bacterium that turns them all into females, so the gall wasps are effectively reproducing asexually (apparently, if the grubs are treated with antibiotics, the wasps return to a 50-50 gender spread).

(*The 'Robin' of the folk name is the woodland sprite Robin Goodfellow, or Puck, who is associated with natural objects which are coloured red.)

Later in the day, we made our way to Hanson Environmental Study Centre, following reports of two Black Terns over the lake. Whilst walking to the Near Hide, we discovered half a dozen Willow Warblers, or possibly Chiffchaffs, taking it in turns to bathe in a puddle.

Although they're ground nesters, it's not often that they're seen on terra firma in the open.

We reached the hide and were just in time to see the terns in the far distance, shortly before they flew off. But Nature's like that, which makes the unexpected surprises all the nicer. As if to prove the point, several metres in front of the hide, we spotted a pair of dragonflies in flagrante delicto amongst the reeds.

Migrant Hawkers, Aeshna mixta, are now a well-established species in the UK, though presumably some migration does still occur from continental Europe. The more, the merrier, as far as I am concerned, and this couple were certainly in agreement in that regard.


Spadger said...

Phylloscopus collybita!

Imperfect and Tense said...

Thanks for the ID. Whether they're tail-flicking or not, isn't much use if they're bathing!

Spadger said...

It's all in the projection, colour and structure!

Imperfect and Tense said...

They were knee deep in water, in the shade of a Hawthorn hedge and flapping like budgies. What projection, colour and structure? :O)

Spadger said...

I have been eating cheese again :0)

Bob Bushell said...

Lovely photos you have made.

Imperfect and Tense said...

Thanks, Bob!