INFORME DESDE UN ANÁLISIS TEÓRICO

Name of recorder/collector (Compulsory). Duration of search (Optional).

Address/phone number (Optional).

Depth (in metres) (Compulsory). Either correct to chart datum, or indicate time of search. 9.2. Surface conditions

All definitions in this section are taken from the MCS form. Wave exposure (Important).

Very Exposed. Prevailing wind and swell. Exposed. Prevailing wind.

Semi-Exposed. Strong wind frequent. Sheltered. Strong wind rare.

Very Sheltered. Fetch 20km. Extremely Sheltered. Fetch 3km.

Tidal stream strength (Important).

Very Strong. 6 knots +. Strong. 3-6 knots.

Moderately Strong. 1-3 knots. Weak. 1 knot.

Very Weak. Negligible.

Salinity (Optional). Would be very useful, however, if the salinity was known, or suspected, to be low.

Normal. Around 34%. Variable. 30%.+. Low. 30%..

Coastal type (Optional). The complete list on the MCS form is Headland, ‘Linear Coast’, Bay, Spit/Bar, Offshore Small

Island, Amongst Rocks/Islets, Sound/Narrows, Shallow Rapids, Sea Loch, Estuary, Coastal Lagoon, Harbour, Sea Cave, Other. In this context, those categories in the second part of the list could be significant.

9.3 Underwater conditions Depth zone (Important)

“The Sublittoral Fringe is the transition zone between the littoral and sub-littoral zones and, on the open coast,

lies above the main Laminaria hyperborea population” Below this, the divisions are: “An Upper Infralittoral where a forest of Laminariales is present”;

“A Lower Infralittoral where Laminariales are absent or sparse but dense algae dominate the rock”; “An Upper Circalittoral where animals predominate but scattered erect algae are present”;

“A Lower Circalittoral where erect algae are absent”.

Note also that “it is most convenient to consider the term infralittoral to apply to any levels that are dominated by subtidal erect algae, as kelp plants are sometimes absent.” (All definitions from Hiscock and Mitchell, 1980).

Substrate (Optional). Interesting or unusual substrates present could be worth recording, but a detailed description is more

appropriate to a habitat survey than a record for an individual sponge. The MCS form contains the following list from which to take descriptions: Bedrock, Large Boulders (0.8m+), Small Boulders (0.5m), Large Cobbles (128- 256mm), Large Slates (128-256mm), Small Angular Cobbles (64-128mm), Small Round Cobbles (64-128mm), Small Slates (64-128mm), Very Large and Large Angular Pebbles (16-64mm), Very Large and Large Round Peb- bles (16-64mm), Medium and Small Pebbles (4-16mm), Clean Gravel (2-4mm), Muddy Gravel (2-4mm), Maerl, Clean Shell Gravel, Muddy Shell Gravel, Coarse Sand (0.5-2mm), Fine Clean Sand, Fine Muddy Sand, Sandy Mud, Mud, Clay, Metal, Concrete, Wood, Other.

Site features (Optional). Any topographical features that could be of interest.

Communities present (Optional). Could be of interest, particularly if the sponge is seen as part of a community (e.g. see

Könnecker, 1973).

Other sponges (Important). It is relevant in this context to record other sponges present in the immediate area, and a note

TECHNIQUES

9.4 Microhabitat information

Any distinctive features of the immediate microhabitat of the sponge should be recorded in particular:

Substratum (Important). Record the substrate to which the sponge was attached. Use the categories from the previous

section, plus living substrate - algae, and other animals (including sponges). Record where the sponge occurred on a living substrate.

Silt (Important). Record whether or not the substratum in the vicinity of the sponge was silty.

Inclination and orientation (Important). Record the inclination of the substrate to which the sponge was attached, and the

sponge’s orientation. Use the categories: Overhang, Vertical (80-100°), Very Steep (40-80°), Steep (20-40°), Shal- low (<20°), Horizontal. Also record whether the specimen was found in a cave, gully, or under a boulder/cobble. Indicate if flush with the surface, above it, below it, or embedded in sediment.

Light (Important). This is obviously affected by inclination and depth (bearing in mind weather conditions and time of day

of observation). It is important to record explicitly whether the sponge is shaded and, if so, by what?

Competition (Optional). Record any competition for space by, or on, the sponge. e.g. was a bryozoan/hydroid “turf” ap-

parently smothering the sponge, or was the sponge overgrowing other sessile organisms?

9.5 Information on the sponge itself

Abundance (Important). The abundance of the species should be recorded, using the following definitions:

Rare : 1-4 specimens per site in 30 minutes. Occasional : 5-24 specimens per site in 30 minutes. Frequent : 25-49 specimens per site in 30 minutes. Common : 50-99 specimens per site in 30 minutes.

Abundant : More than 100 specimens per site in 30 minutes.

These definitions, adapted from Hiscock, 1979, can be difficult to apply precisely. However, subjective judgement, acquired with practise, can be almost as valuable. The definitions apply to massive sponges and so different criteria may need to be used for erect branching forms, crusts and purse sponges.

Silt (Important). Whether the surface is clean, covered with silt (or epibiotic material) should be noted. Associations (Important). Record any other organisms that are feeding on, or living on, or in the sponge. Photographs (Important). Record whether there are any photographs of the sponge.

Accession number (Important). It is useful to have a numbering system to identify uniquely the specimen in your collection.

Prefix it, e.g. with your initials, to avoid confusion with the specimens of others, should you send your specimen to someone else. This helps keep slides, photographs and specimens linked together.

0 St. Kilda Orkney Shetland Skye Strangford Lough

Lough Hyne Milford Haven, Daucleddau Galway

Bay

Kerry Saltee Is.

Donegal Bay Firth of Lorne Sound of Jura Skomer Lundy Blasket Is. Valentia Aran Is. Calf of Man Anglesey Menai Straits St. John's Point Mull Rathlin Plymouth Scilly Is.