Saturday
Dec182004

The 'Strange Duck' is a Snow Goose?

This afternoon I also got some photos of the 'strange duck' that Zoe and I first saw a couple of weeks ago.  I now reckon that this bird is a blue-phase snow goose [However, see update below].  The snow goose (Anser caerulescens) comes in two colour phases: the more common white phase which is mainly white but with black wing-tips, and the blue phase which is mainly black but with a white head.  The illustrations in BWP-CE and photos on the web do not give any indication of the beautiful scale-pattern in black and dark green that was visible on the back of our bird.  In some lights the dark green turned to a dark blue  (presumably this is where the term 'blue phase' comes from).  Here is one of the photos I took today:

blue-phase-snow-goose.jpg

Again, this bird was fairly persistent in begging for food: it got out of the water when Zoe rustled an empty carrier bag, which none of the other birds did, and I reckon Zoe could have had it eating out of her hand if only she had had some bread left.  This familiarity with human beings suggests an escaped captive bird rather than a vagrant that has wandered in from North America or Siberia.

Saturday
Dec182004

Shoveler Ducks

This afternoon Zoe pointed out a strange grouping of ducks right in the centre of the largest of the Reading University lakes.  There were about twenty ducks all swimming around in a circle no greater than about 2 metres in diameter.  They seemed to be a mixture of males and females, the females being a drab light brown colour, but the males having black heads, a large white patch covering their breasts and shoulders, a large reddish-brown patch on their sides, and a smaller white patch under a black tail. 

As they were a long way out and did not seem to be interested at all in the bread that we were throwing, so we could not get a close look at them.  However, I am fairly confident that they were shoveler ducks (Anas clypeata).  We were not able to clearly make out their characteristic 'shovel' bills, but when we go back tomorrow morning I will be taking my binoculars with me. 

The densely-packed flock was probably feeding (BWP-CE states "Most likely to congregate densely when feeding" and also notes that they tend to gather in flocks of 20-30).  They feed on small animals and plant debris that they suck up with their 'shovel' bills.  The flock were probably swimming in a circle in order to create a whirlpool to stir up food from the bottom.

Sunday
Dec122004

Goldcrests, Cormorants, etc

On our Sunday morning walk around the Reading University lakes, Zoe and I saw a goldcrest.  It was in a small leafless tree only 3 metres away and it didn't seem to be bothered at all by our presence.  It fitted about from twig to twig, sometimes hanging upside down.  We watched it for about 30 seconds, and followed it when it flew to another tree nearby.  Its crest was a pale yellow colour which I take to indicate that it was a female, though I suppose it is just possible that males lose the redness in their crests in the winter.  When  we got home again I did consider the possibility that it might have been a firecrest, but discounted this when I read in BWP-CE that the British population of firecrests was only a few hundred, whereas the population of goldcrests is around a million.

We also saw four cormorants on the lake.  Two of them seemed to be paired up - when one flew off the other followed.  One of the other two was distinctly smaller than the other three - maybe it was a juvenile.  We later saw the small one fishing - swimming around with its body very low in the water and then suddenly diving below the surface.

We also saw our strange duck again, the one with the white head and the greenish black body.  Its head was more white with small dark patches, than the pure white that I implied in my earlier account.  Also, its legs were a pale buff colour rather than yellow.  It again was very forward in coming to beg for food.  It was definitely not a mallard.

Friday
Dec102004

Bertrand Meyer's Word Games in OOSC2

In his magnum opus, Object Oriented Software Construction (2nd Edition), Bertrand Meyer refrains from explicitly mentioning 'Eiffel', the name of the programming language he is expounding, until the very end of the Epilogue.  However, it is fairly well known within the Eiffel community that 'EIFFEL' is encoded in the first letters of the text of chapters 1 to 6.  Well, that is not the end of Meyer's word games.  After a little research, I have discovered the following:

The first letters of each of the 36 chapters are, in order:

EIFFELEIFFELEIFFELEIFFELEIFFELEEIFEL
That is, five EIFFEL's followed by an EEIFEL.  Presumably chapters 32-33 have been changed since the first edition.  Maybe someone could check this out for me?

Following chapter 36 there is a two-page epilogue entitled:
Epilogue, In Full Frankness Exposing the Language
The first letters of this, ignoring the 'the', spell out EIFFEL.

The epilogue also consists of six paragraphs, the first letters of which spell out (yes you've guessed it) EIFFEL.

 

Tuesday
Dec072004

Pied Wagtails

This afternoon at 1pm, as I was walking along Station Road from Reading station towards the town centre, I saw a pair of pied wagtails (Motacilla alba yarellii) fly down onto the path in front of me. They then flew up a metre or two and then came down again onto the road.  Fortunately there were no vehicles around.  As it was lunch time, there were lots of people hurrying along the path but the wagtails seemed more interested in each other.  One of the pair was a classic pure black-and-white pied wagtail while the other had a distinctly greyish back.  Maybe the latter was actually a white wagtail (Motacilla alba alba)?

In the past few years I have most often seen pied wagtails on summer mornings in the Frimley Waitrose car park and on its approach road, Hale Way.  Back in the late 1990's I also used to regularly see some at Ascot station as I waited on platform 3 for my connection to Frimley.