THE ESSEX NATURALIST
Journal of the
ESSEX FIELD CLUB
No 19 (New series)
For the year 2001/2002
ISSN 0071-1489
Editorial team: Dr Ken Adams, Dr Peter Allen, Dr Jeremy Dagley,
Dr Chris Gibson, Mr Peter Harvey (Technical Editor)
Copyright © Essex Field Club 2002
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or
transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise,
without the permission of the Essex Field Club or the copyright owner.
Information published in this journal may be freely quoted provided that
full acknowledgement is made in the normal manner to both author and journal.
Readers are advised that publication of material in the Essex Naturalist does not
imply, unless indicated to the contrary, that the views and opinions expressed
therein are shared by the editors or by the Council of the Essex Field Club.
Published by the Essex Field Club
c/o School of Bioscicnccs, University of East London, Romford Road, Stratford, London E15 4LZ
www.essexfieldclub.org.uk
Printed by Jenner (City Print). Tiptree