(A look at the winter shore)
Text by Brian Darnton, UK. Images by Jan Parmentier, The Netherlands.
This is an expression much used in its widest sense by people generally. It is an abbreviation for the saying 'Its an ill wind that blows no one some good.' and simply means however unfavourable, conditions may be, there is always someone or something that will benefit from them.
Paddling in tranquil pools with net poised or snorkelling amongst the gently waiving laminaria fronds during the elusive heat of summer are but a dream during the strong gales of winter time. Most would say that itís a time for microscopy indoors, and so would I, until I chanced upon a booklet by Peter J. Hayward called Animals on Seaweed (ref. 1).
Above and right. Bryozoans from the genus Electra, showing the delicate calcified tissue.
The other images below are bryozoans mainly from the British Isles.
Its full of good ideas, but what gripped me was the riches afforded by the holdfasts of the great seaweeds. Many of them have a swollen base behind the point where they are rooted into the sub-stratum. The stem is often swollen and within this cavity is a protected El Dorado for creatures great and small. During the winter gales, even the most titanic growths are uprooted and cast up on the rocks.
After deposition, many of the motile creatures certainly make a break for it and disappear into the sub-littoral zone, but those that are stuck to the walls of the cavity have no option but to hang on where they eventually dry out and die. The iridescent shell of Patina can frequently be found but the best represented group of animals is that of the Bryozoa: The sea mats can be seen in great variety. They can be freed with a scalpel, then cleaned in hydrogen peroxide for a couple of days and just as skeletons make aesthetically very pleasing objects for the low powers. The genus Electra is well represented on the South coast and it will attempt to encrust a wide variety of objects. The calcified matrix is finely ornamented with lace-like frills and around the apertures are protective spines. There are often so many sea mats that a text book is really required to sort them out. Once again Mr P.J. Hayward and a colleague Mr. J.S. Ryland have come to our rescue with a series of books, one for each of the major groups (ref. 2).
Most of the colonies require only dry mounting but some of the more delicate growths which can be found encrusting the finer seaweeds, may be washed, desiccated and mounted in Canada balsam where their finer points can be appreciated.
At this inhospitable time of the year the tide marks of the sheltered bays also become enriched with detached bryozoan encrustations and also spicules from sponges and suchlike colonies broken by the heavy seas over the off-shore reefs. Winter storms also seem to churn up the deeper parts of the bays and deposit crops of Foraminifera tests, particularly when the winds combine with the spring tides. The images shown are but a small representation of the diversity of bryozoans.
All comments to the author Comments to the author sent via our contacts page quoting page url plus : ('bdarnton','')">Brian Darnton are welcomed.
1) Peter J. Hayward "Animals on Seaweed". Naturalist Handbook No 9. Published by Richmond Publishing Co.Ltd. ISBN 085546 265 5
2) Mr P. J. Hayward and Mr.J.S. Ryland diverse works include the following booklets published by the Linnean Society together with the Estuarine and Brackish-water Sciences Association.Cheilostomata Anasca Bryozoans, (10), 1977. (ISBN 0-12-605250-6)
Cheilostomata Ascophora Bryozoans, (14), 1979. (ISBN 0-12-335050-6)
Ctenostomata Bryozoans, (33).
Cyclostome, Bryozoans, (34), 1985. (ISBN 90-04-07697-2)
Below is a live bryozoan colony in 'summer plumage'.
Please report any Web problems or
offer general comments to the
via the contact on current Micscape Index.
Micscape is the on-line monthly magazine
of the Microscopy UK web
site at Microscopy-UK