Boring sponges and the modeling of coral reefs in the east Pacific Ocean

Abstract

A total of 900 coral fragments collected across 2 fringing reefs located southwest of Mexico, La Entrega (LE) and San Agustín (SA), were examined for the presence of boring sponges. Of all samples, 43% were invaded by boring sponges, and 7 species belonging to 5 genera (Aka, Cliona, Pione, Cliothosa and Thoosa) were identified. The most abundant species were Cliona vermifera (17.9%), Cliona sp. (10.8%), A. cryptica (7.8%) and P. carpenteri (6.0%). The distribution and abundance of the species varied considerably throughout the reef area (margin and platform) and displayed certain selectivity for specific calcareous substrata. C. vermifera, Cliona sp., A. cryptica and P. carpenteri were most common on the reef margins, while T. calpulli was common on the central platform. A. cryptica, P. carpenteri, and Cliothosa hancocki were frequently found living in the immediate vicinity of live coral tissue, contrary to C. vermifera, T. calpulli and Cliona mucronata, which preferentially bored coral rubble. The results showed that reef margins had a significantly higher infestation level than the platforms (mean infestations of 60.6 and 26.2%, respectively). There were also differences between reefs. The infestation was higher on LE than on SA (48.6 and 38.2%, respectively), and these differences were larger between the platforms of the 2 reefs (41.3 and 11.1%, respectively). In general, the results of the present study have demonstrated that the diversity and abundance of species, as well as the infestation of coral frameworks by sponges, was significantly higher in the margin at both reefs studied and on the platform of LE, where the availability of exposed carbonate substrate was higher. In the margin of these reefs, the consequences of boring went far beyond the mere hollowing out of a few cavities, since by weakening the coral's attachment to the substrate, the sponges accelerated coral loss and restructured the reef edge. This pattern may have important implications for the preservation of the reef framework. KEY WORDS: Bioerosion · Boring sponges · Fringing coral reefs · Reef margin · Reef flat · Mexican PacificResale or republication not permitted without written consent of the publisher Mar Ecol Prog Ser 356: 113-122, 2008 different types of organisms, which act on the environment in a wide variety of ways, interact with the ecosystem and with each other as part of the cycle of reef growth and degradation (Macdonald & Perry 2003). Amongst these, the boring sponges are considered one of the main agents that modify coral reef ecosystems (Goreau & Hartman 1963, MacGeachy 1977. Globally, they are the most common type of macroendolith and are responsible for more internal degradation of coral than any other group of organisms, internally (Perry 1998). They can accelerate the erosion of the reef framework (Tunnicliffe 1979) and cause a shift in the carbonate balance (Rose & Risk 1985). Sponges obviously play one of the most important roles in bioerosion worldwide. However, they have been omitted in most stud...

Combined Effects of Experimental Acidification and Eutrophication on Reef Sponge Bioerosion Rates

“…Sponges and other borers are assumed to benefit from eutrophication (Holmes, 2000;Carballo et al, 2008). Many sponges on reefs harbor photosynthetic symbionts and in some cases they produce >50% of the energy requirements of the host (Erwin and Thacker, 2008).…”

“…Bioeroding sponges contribute between 60 and 90% of total macroborer activity on coral reefs and their (surface-normalized) erosion rates have been found to equal and even surpass calcification rates of hermatypic corals (MacGeachy and Stearn, 1976;Hudson, 1977;Edinger et al, 2000;Carballo et al, 2008;Perry et al, 2014). Bioeroding sponges use a combination of chemical dissolution and mechanical CaCO 3 chip removal to erode coral substrate (Nasonov, 1924;Rützler and Rieger, 1973;Pomponi, 1980).…”

Chemical and mechanical bioerosion of boring sponges from Mexican Pacific coral reefs

“…Sampling was carried out by scuba diving, collecting 25 fragments of the basal portion of live corals approximately 90 cm 3 along 10 transects 25 m long perpendicular to the shoreline (Carballo et al, 2008). The samples were examined in the laboratory for the presence of boring sponges.…”

“…The species richness and abundance as frequency of invasion (IF) of boring sponges was quantified by examining living colonies of P. verrucosa (Carballo et al, 2008). Sampling was carried out by scuba diving, collecting 25 fragments of the basal portion of live corals approximately 90 cm 3 along 10 transects 25 m long perpendicular to the shoreline (Carballo et al, 2008).…”

“…This work had four goals: (1) to study the species richness (S) and the frequency of invasion (IF) by boring sponges on living colonies of Pocillopora verrucosa (Ellis and Solander 1786) at Isla Isabel; (2) to quantify the carbonate dissolution rate of Cliona vermifera Hancock 1867 and Cliona flavifodina Rützler 1974, two of the most abundant and amply distributed boring sponges from the east Pacific Ocean (Carballo et al, 2004;Carballo et al, 2008). This is especially important to ensure the validity and generality of previous results for Pione cf.…”