is also melting, but irregularly, so that some ice sheets are slightly increasing while
others are shrinking faster. This will add more to our rising sea levels, though perhaps
more slowly. Essex will have sea lagoons (extensions of the Mardyke) in inland areas
that are low-lying such as the Bulphan Fen area just north of Orsett and not a million
miles from my home. Upminster itself is at about 25m above sea level, so should be OK,
but we shall meet the coast just south of Aveley, where the present lower Mardyke will
have become sea. At my favourite Belhus Woods Country Park they will be selling ice
cream and candy floss and renting out deck chairs and organising donkey rides on the
sands. The whole of Canvey Island will disappear under the sea, as will huge areas of
flat land, formerly Saltmarsh, north and east of Great Wakering, just outside Southend.
Burnham-on-Crouch can change its name to Burnham-on-Sea and Maiden round to
Brightlingsea will be under water, as all the rivers grow in width and decrease in length.
The two big questions are: how long will this take? And can we stop it? The answers to
both must be: nobody knows. Thank you, Ken, for alerting me to all this.
Soon after Christmas I had a phone call from Alf Gudgeon about the habits of foxes,
related to my item in the Newsletter number 54, September 2007. I had been told about
magpies mobbing a fox, and the fox just slipping away into bushes where the magpies
could not get it, and I had thought it strange that the fox did not fight the magpies off. Alf
told me that foxes will always go for self-preservation above all else, and very rarely
take on a fight with any other animal. He agreed that the magpies were almost certainly
after some food the fox had found, and they would have pestered the fox until the food
was dropped. Birds in the crow family all have vicious beaks, and it is well known they
go for eyes, and a blind predator soon dies, so whether taught by its parents or by
instinct, the fox 'knows' not to fight a big-billed bird. A fox and a cat will not pick a fight
either, but each just walks past the other, completely ignoring each other. Thank you,
Alf.
Still in late December, we were walking in Hornchurch Country Park and we watched a
kestrel hover over rough grassland ahead of us. As we drew nearer, the kestrel moved to
the other side of the path, about 10-15m away, and perched in a small tree. Suddenly, it
swooped past us and picked up a small mammal from below where it had previously
been, and flew off with it, not pausing at all in its flight. We were amazed at the acuity
of vision the kestrel must have, and also by the swooping flight that caught the mammal.
We had never seen a kestrel actually catching its dinner, but on this occasion we saw it
well as we were very close. It was an impressive sight to witness. Note, later: we have
just been reading some scientific advances in the understanding of vision in animals,
mainly vertebrates. Most birds can see in the near ultra-violet, which most mammals,
including humans, cannot. And voles of various kinds have scent glands which strongly
reflect ultra-violet light. So Kestrels can pick out voles with much greater ease than we
ever could. And Blue Tits should be called Ultra-violet Tits, as the 'caps' on their heads
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Essex Field Club Newsletter No. 56, May 2008