SEABED PROFILES

In 1991, seabed profiles were taken at each of the 27 sites dived around Henderson, 4 at Oeno and 4 at Ducie. No diving was undertaken at Pitcairn. Profile records from dives sites all the way round Pitcairn, will assist in the assimilation of a complete the picture.

BEACH LITTER SURVEYS

In 1991 a survey was carried out of all the items of litter encountered on a 1 km stretch of beach at Ducie. (It took the one person about 4 hours to do this). Over 400 items were found and listed. A later report of the results in a scientific journal was picked up by the national press and gave the expedition considerable publicity. The same survey could be repeated at Ducie, Henderson and also at Pitcairn. (Oeno is not suitable as it has a reef all around the lagoon/atoll, and consequently very little litter reaches its shoreline).

CROWN-OF-THORNS STARFISH SURVEYS

Crown-of-Thorns starfish (Acanthaster planci) pose a well-known threat to coral reefs as they eat coral polyps. Of course they are not the only reef creatures to do this, but these starfish can appear as if from nowhere in huge numbers and can be resposible for killing off large areas of reef in a very short space of time.

One C-o-T starfish was reported from the lagoon at Ducie in ?1978 by a small group of American scientists looking at the fish there. In 1991 a group of about 200-odd were encountered at one dive site off the NW coast of Henderson at about 18 m depth. Expedition divers would be asked to keep a look out for these starfish on all dives, with further survey work being undertaken should more than one individual be found. The survey would involve measuring the number of starfish present and the area/depth range they were found in.

SEASEARCH SURVEYS

SEASEARCH is a survey methodology devised and run by the Marine Conservation Society. Put simply, its aim is to encourage volunteer sports divers to record what they see on their dives, noting particular features of the seabed and its associated communities. It is split into three levels, the simplest one being ‘Stage 1’, which is the one we would undertake. Whilst being designed for describing temperate water seabed types and communities, it can also be adapted for use in tropical waters. Prior to departure from the UK, a ½-1 day SEASEARCH training session would be organised for all expedition members.

CORAL BLEACHING/CORAL DISEASES SURVEYS

Positive identification of the presence of coral bleaching and/or coral diseases often requires in situ confirmation from a coral specialist. However, photographic evidence may be sufficient in some cases to allow for such confirmation. Coral bleaching (where individual corals are stressed to such an extent that they expel their symbiotic algae and thus appear ‘bleached’ white) is likely to be apparent in shallow water corals, particularly those present in the lagoons of Oeno and Ducie. Linked in with these observations would be recording sea water temperatures at all four islands.

Collection of Hydroid Species for Southampton University

Whilst diving during exercise 'Bounty Bay' we shall be collecting Hydroids. Like corals and sea anemones hydroids are members of the phylum cnidaria, they belong to a class of which there are an estimated 10,000 species that also includes fire corals, hydrocorals and floating colonies such as Portuguese man o' war.

There is an interest in hydroids at Southampton Oceanography Centre and there has been assistance from several expeditions around the world in the collection of hydroids. During our expedition hydroid specimens will be collected, preserved and accompanied by as much detail as possible about where the specimens were found. They will be transported back to Southampton Oceanography Centre for identification.