Current status
The sunset cup coral Leptopsammia pruvoti occurs in groups of a few tens to several hundred individuals. It is found attached to rock, at a small number of isolated locations, in south-west England. In other parts of the north-east Atlantic it has been recorded in the Channel Isles, Brittany and Portugal and occurs widely in the Mediterranean, especially in caves. It has not been recorded, despite targeted survey, in Madeira and the Azores. It was first recorded in Britain from Lundy in 1969.
The coral is solitary, but occasionally found as small pseudo-colonies. The skeleton is porous and the calice round, becoming elliptical with age. The corallum may be short and cylindrical or tall and inversely conical, up to 60 mm in height, and with a calyx diameter up to 17 mm. The disk and tentacles are usually yellow, sometimes orange. There are about 96 tentacles. Sunset cup coral prefers shaded bedrock habitats (for instance, under overhangs and in caves or gullies).
Populations at Lundy and the Isles of Scilly have been monitored for 12 years and have shown no or negligible recruitment. The Lundy population had declined by 22% between 1993 and 1997. Studies of sunset cup coral in aquaria suggest that both juveniles, settled from planulae, and mature individuals, are very robust and cope well with extremes of temperature, starvation and slight variations in salinity.
The sunset cup coral may be found in the following JNCC Marine Nature Conservation Review (MNCR) biotope: Sponges, cup corals and Parerythropodium coralloides on shaded or overhanging circalittoral rock (CR.SCup).
The sunset cup coral is not protected under any UK statutes or listed in Directives and Conventions.
Current factors causing loss or decline
There are several possible reasons why sunset cup coral has a restricted distribution and is in decline. They are listed in a suggested priority order, but little observational or experimental work has been undertaken to establish either status or decline.
Populations are at the northern limit of their distribution and may be a relic of a former, more extensive distribution approximately 700 years ago. They are now restricted to ideal locations.
Populations recruit extremely infrequently because of water temperature conditions being inadequate to allow production of gametes or gametes to be produced synchronously. However, viable larvae have been produced from individuals collected from Lundy and successfully placed in aquarium tanks on three occasions.
Adult populations decline because of lack of recruitment. This could be because larvae are swept away by tidal currents and fail to settle on suitable habitats or are consumed by attached carnivorous animals before they settle.
Non-recruiting populations decline because of weakening of the skeleton by boring organisms and subsequent detachment by such agents as foraging wrasse or divers finning.
Recruitment into populations may occur from distant sources such as populations to the south in continental Europe and only when appropriate water bodies move into south-west England. There is evidence that this sort of movement of water bodies might occur every 25-30 years.
Current action
The awareness amongst divers of the long life and slow growth of sunset cup coral has been promulgated since the mid 1970s and it is important to retain this education.
Studies of the longevity and persistence of sunset cup coral at monitoring sites at Lundy continue together with observations of degree of infestation with boring species. Aquarium observations are also helping to understand more about reproduction and maintenance of healthy individuals.
The general public's awareness of this species and of more general marine conservation issues has been raised through publicity and educational material associated with the Lundy Marine Nature Reserve (MNR).
Action plan objectives and targets
Maintain the distribution of known viable populations and those identified by the 2004 baseline.
Maintain the size of known viable populations and those identified by the 2004 baseline.
Proposed actions with lead agencies
Policy and legislation
None proposed.
Site safeguard and management
Ensure that the management of Special Areas of Conservation (SACs) and MNRs takes account of sunset cup coral. (ACTION: NE)
Ensure that locations with significant populations of sunset cup coral in statutory and non-statutory (voluntary) marine protected areas are identified as being of appropriate sensitivity within management zoning schemes. (ACTION: NE)
Undertake management measures to ensure human activities do not compromise known populations of the species. (ACTION: NE)
Species management and protection
Ensure that populations of sunset cup coral are protected through the implementation of management measures in Marine Conservation Areas (MCAs). (ACTION: NE)
Advisory
Increase awareness among coastal zone management groups of the sensitivity of sunset cup coral in locations where it is known to exist. (ACTION: NE)
Determine the causes of decline and take management action if the decline in the population of sunset cup coral is believed to be due to human factors. (ACTION: NE)
Future Research and Monitoring
Continue to monitor the abundance and condition of sunset cup coral as part of established monitoring work and ensure that it is included in SAC monitoring programmes, where appropriate. (ACTION: NE)
Undertake work to understand the factors that affect recruitment and survival of sunset cup coral. This requires a programme of ex situ studies of reproduction to include establishing ‘triggers’ to reproductive success, nature of the larva, time to settlement and factors affecting successful establishment and dispersal. Sites at the present limit of distribution should also be included. This can be linked to long-term monitoring of climate change. (ACTION: NERC)
Communications and Publicity
Ensure that information on the long life and slow growth rates of sunset cup coral continues to be promulgated to divers through leaflets, posters, displays and talks. (ACTION: NE)
Use sunset cup coral as an example of a rare, long-lived species to increase awareness of marine biodiversity at public aquaria. (ACTION: NE)
Links with other action plans
None given.
Local implementation
The following LBAPs are working on Leptopsammia pruvoti:
Publication details
Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume V: Maritime species and habitats (October 1999, Tranche 2, Vol V, p87)
Related links
ARKive Visit the ARKive website to view images and further information relating to this species