Bulletin 20 - July 1983: New Procedure for Marine Fish Observations/Recordings
New Procedure for Marine Fish Observations/Recordings
by R.W. Brown
The purpose of this article is to introduce a new observer recording
technique to the ENHG. A new recording form has been drawn up which will be
discussed along with a typical example of its use. It is not intended, at this
stage, to go into the precise detail of marine fish identification. However,
those interested in the basis of such identification may refer to the article in
Bulletin No.4, pp. 24 -26.
The Observer Recording Form
A completed example is attached to this article. As can be seen, the form is
divided into two parts, the first to be completed by the observer and the second
by the marine recorder later.
The first section is subdivided into seven parts (A -G) which, if completed
accurately, should enable a positive identification to be made. In order to
assist observers, two visual aid reference sheets have been prepared, viz:
- Diagramatic Sheet 1: Body Shapes
- Diagramatic Sheet 2: Head and Tail Shapes
These sheets, in conjunction with the observer form, provide a simple
'identikit' reference for use on site. It should be noted that if a particular
fish spotted corresponds exactly with that on Diagramatic Sheet 1, then the head
and tail references can be omitted. The reference sheets are designed for
simplicity, but such sheets are rarely complete, there usually being another
species to be discovered. If a body shape does not appear to be covered, there
is a space on the form for a sketch. The same applies for heads and tails.
Examples
The following completed form is based on the information for the fish Thalassoma
lunae (see preceding article). The marine recorder will have received
the observer's form and attempted a positive identification. This, of course, is
made all the easier if accurate and concise data are provided. After
identification the record is entered or a new record card made out, as
appropriate.
Further Study
Practice in the use of the reference sheets and completion of observer forms
could be obtained by attempting to write down the pertinent details from marine
fish articles in previous Bulletins. A list of articles is attached.
Once the principles of fish recording are generally understood, prospective
observers should get out and observe, remembering to take out blank forms and
reference data (perhaps in plastic covers). Completed forms should be returned
to the marine recorder or any ENHG Committee member.
Handling Fish
There are only two methods of observing fish specimens - in the wet or in the
dry. Safe handling procedures for fish out of water are very important. Dorsal
and anal fins contain sharp spines which in some species are poisonous.
Furthermore, some fish can survive for several hours out of water and still
bite. A good pair of gloves come in handy when examining any specimen, whether
dead or alive.
Divers observing in the water should also take care. Most fish will swim away
from fear, but some, especially the stone fishes, do not. These fish, Family
Synanceiidae, are rarely found in Abu Dhabi inshore areas but are common along
the east coast. They will sit quite happily on a stone or rock and strike when
approached. A sting from the dorsal spine of a stone fish is at best very
painful and can be fatal. However, the rewards of underwater observing are well
worthwhile. Photography provides one of the best general methods of fish
recording, but fin counts are virtually impossible. It is hoped that these notes
will spur on would-be observers to become active in completing the forms.
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