Occurrence and Distribution of an Invasive Octocoral, Carijoa riisei in Malaysia’s Marine Park of Pulau Payar

The occurrence of the invasive snowflake coral, Carijoa riisei (Duchassaing & Michelotti, 1860) in Malaysian waters was reported after the species was first detected at Pulau Payar Marine Park in 2014. Its recent appearance in Pulau Payar highlights the need for baseline data concerning the distribution pattern and diversity of C. riisei within the Pulau Payar Marine Park and may enable effective remedial actions in controlling the overgrowth of this octocoral. The snowflake coral and other substrates were quantified over quadrats located randomly on a 50 m transects in three study sites, i.e. Coral Garden, Kaca Reef and Lembu Rock. The percent cover of each substrate category and diversity were determined using the Coral Point Count with Excel extensions (CPCe) software. The snowflake coral was most frequently observed at the depths of 10 to 20 m at each of the study sites. The area with highest coverage of this octocoral was in Kaca Reef at the depth of 20m. About one-third of the benthos and abiotic substrate at all sites was populated by C. riisei. Statistically, no significant differences were found between the distributions of C. riisei by sites. Using diversity indices, we were able to demonstrate the ability of this species to exploit a wide range of differing environments. This ability has allowed it to spread within this marine protected area. Based on this study, we suggested monitoring programs should be regularly conducted within Pulau Payar Marine Park, other reefs should be surveyed for its presence, and an effective mitigation program should be developed for the conservation of the marine ecosystems affected by this invasive species.

Molecular markers confirm the presence of the alien snowflake coral Carijoa riisei (Octocorallia: Alcyonacea) in Cabo Verde Islands (Central-East Atlantic).

The snowflake coral Carijoa riisei is one of the most invasive and successfully adapting species in the coastal marine environment. This species can disperse through ballast waters or fouling on the hull of ships, which allows it to expand very quickly to areas where it is not native. Recently C. riisei was identified in the Porto Grande Bay in São Vicente island in Cabo Verde Islands. We analysed mitochondrial and nuclear DNA sequences from specimens collected at this locality to determine the potential origin of this invasion. Lack of genetic variation in both mitochondrial and nuclear genes suggest a very recent invasion (bottleneck effect) but did not permit to establish its origin with total confidence.

DIVERSIDAD, ABUNDANCIA Y AMENAZAS DE LOS OCTOCORALES DE LA ISLA MALPELO, PACÍFICO ORIENTAL TROPICAL, COLOMBIA

During three expeditions to the island (2009 and 2010), the diversity, abundance and status of octocorals were explored. Seven species of octocorals were recorded: Leptogorgia alba, Pacifigorgia cf. lacerata, Pacifigorgia sp.1 y Pacifigorgia sp.2, Muricea cf. fruticosa, Muricea sp., and the invasive species Carijoa riisei. Octocorals form dense aggregations in rocky walls and cliffs, with higher abundances between 10 and 20 m, reaching up to 20 colonies m-2. The most abundant species was Pacifigorgia cf. lacerata with a dominance of more than 60 % and a frequency of occurrence of 100 % for all visited sites. According to depth, three well-defined zones were determined for most sites. A deep zone between 25 and 40 m with an exclusive dominance of L. alba, a shallow assemblage between 7 and 20 m dominated by Pacifigorgia spp., and a transition zone between 18 and 25 m with a mixture of L. alba and P. cf. lacerata. Surprisingly, during November 2009, diseases of possible fungal origin visibly affected populations of Leptogorgia and Pacifigorgia. Subsequently, during February 2010 the same populations of octocorals were monitored and up to 66 % of the colonies were already dead in some locations. Leptogorgia had a significant reduction at El Arrecife site, while Pacifigorgia cf. lacerata had high mortality at La Nevera and El Freezer sites, and a recovery in El Arrecife. There was a notable improvement in disease prevalence by July 2010 with less than 10 % of diseased colonies. The invasive species C. riisei was observed in La Catedral and El Monstruo bank. Thus, this information increases considerably the knowledge of octocorals on Malpelo Island and is the first warning of possible threats against local octocoral populations, such as fungal diseases and the invasive octocoral C. riisei.

PRESENCIA DE LOS OCTOCORALES STYLATULA DIADEMA BAYER (PENNATULACEA) Y CARIJOA RIISEI (DUCHASSAING Y MICHELOTTT) (TELESTACEA) EN LA COSTA CARIBE COLOMBIANA.

Through SCUBA and skin diving various shallow water ecosystems (rocky shores, soft bottoms and coral reefs, 0-30 m deep) were surveyed to collect telestaceans and penatulaceans octocorals; the areas considered were Cartagena, the Rosario islands, Tierra Bomba island, Barú island, San Bernardo islands, Bushnell and Salmedina banks, Capurgana and Zapzurro harbours (8°20,-10°45, N; 75°50,-77°251 W), the Santa Marta area (11°14,50" N; 74°15, W) y and the Guajira (11 °56,58" N; 72°16'18" W), Colombian Caribbean. Stylatula diadema Bayer (Virgulariidae: Pennatulacea) is first recorded for the Caribbean sea and has been found inhabiting soft sand bottoms between 25 and 30 m, at the outer end of Cartagena Bay and the Mangles Bank in San Bernardo islands. The geographic distribution of Carijoa riisei (Duchassaing y Michelotti) (Telestidae: Telestacea) was widen from the Caribbean and Colombia, it has been found in a broad bathymetric range (0.5-30 m) in all the habitats surveyed. Few records of telestaceans and pennatulaceans in this region, as in the rest of the Caribbean, suggest that the octocorallian fauna is mostly represented by gorgonians than by other orders, and shows an inverse relationship with the Indopacific fauna, where the alcyonaceans are the dominant order.