Boring by Macro‐organisms in the Coral Montastrea annularis on Barbados Reefs

Abstract

The fauna boring into Montastrea annularis includes sponges" bivalves, sipunculid and polychaete worms and barnacles. Sponges.and spionid polychaetes are most important in hard tissue destruction and <II account for more than 90% of the total boring in mast heads. Bivalves and ,barnacles are locally import~nt. Sipunculids and sabellids account for less than 4% of the total bor~ng.,)The vol"me removed from,coral sar'ples by boring rangcd from ' .

Fauna living in colonies of Mussismilia hispida (Verrill) (Cnidaria: Scleractinia) in four South-eastern Brazil islands

“…These, are attached to the coral bases, bore the skeleton, or live over or under the colonies (McCloskey, 1970;Young, 1986;Arvanitides and Koukouras, 1994). Many authors have emphasised the destructive impact of the endolithic fauna on coral colonies, a process known as bioerosion (Hein and Risk, 1975;MacGeachy and Stearn, 1976;Hutchings, 1986;Kiene and Hutchings,1992); among the studies with a more specific focus, those on sponges (Rützler, 1975), molluscs (Hadfield, 1976;Morton, 1983;Moretzsohn and Tsuchyia, 1992), polychaetes (Kohn and Lloyd, 1973;Arvanitides and Koukouras, 1994;Nogueira, 2000), and sipunculids (Rice, 1976;Rice and Macintyre, 1982) should be noted.…”

“…According to Fauchald and Jumars (1979), the feeding guilds of the most representative families of polychaetes in the present study observed suggested that they were very important on these communities, controlling populations of microcrustaceans, feeding on suspended materials, and on detritus and bacteria entrapped in coral mucus. Other well known group of endolithic animals is that of bivalves, whose importance should be seen in terms of making great holes at the corals bases, causing their dislodgement from the substrate (MacGeachy and Stearn, 1976;Hutchings, 1986), rather then in the number of specimens; another role of them is increasing the available space for larval settlement of other borers (McCloskey, 1970). The most studied group of boring bivalves is the subfamily Lithophaginae (family Mytilidae), in which this habitat has evolved from earlier forms attached to the substrate (Yonge, 1955).…”

Spondylus crassisquama Lamarck, 1819 as a microecosystem and the effects of associated macrofauna on its shell integrity: isles of biodiversity or sleeping with the enemy?

“…We found members of several polychaete families known for boring; Eunicidae, Sabellidae and Spionidae, represented here by the genus Polydora (Haigler 1969;MacGeachy and Stearn 1976;Davies and Hutchings 1983). Previous studies have shown that boring polychaetes can weaken corals (Wielgus et al 2006) and have deleterious impacts on bivalves and gastropods of economic significance.…”

“…We could not identify the sipunculid genus we found; however, the specimens and their boreholes very much resemble examples of the genus Phascolosoma given by Rice (1969) and MacGeachy and Stearn (1976). They assume a combination of chemical and mechanical drilling for sipunculids.…”

“…To obtain a more detailed picture of the co-existence between S. crassisquama and associated endobionts, we will thus especially discuss the taxa we found that are known for drilling or boring activities and their effects on the Spondylus shell: Sponges Sponges account for a considerable amount of boring in corals (MacGeachy and Stearn 1976; Sammarco and Risk 1990;Pari et al 2002). We were not able to identify the sponge species in our samples, but when breaking and analyzing the shells, we found the typical honeycomb boring style reported for the genus Cliona (Cobb 1969;Rützler and Rieger 1973;MacGeachy and Stearn 1976), and assume Mar Biodiv that at least one member of that genus was present. Sponges drill delicate networks, but when breaking our thick sample shells, their stability appeared to be little affected even in heavily bored areas.…”