The distribution and prevalence of sponges in relation to environmental gradients within a temperate sea lough: vertical cliff surfaces

Abstract

The prevalence and distribution of sponges was surveyed on vertical cliff surfaces at Lough Hyne Marine Nature Reserve, Co. Cork, Ireland. The number of sponge species was recorded at 6-metre depth intervals at four sites within Lough Hyne, and at one site on the adjacent Atlantic coastline to examine differences in abundance and zonation patterns. Sites ranged from an exposed turbulent regime to sheltered, sedimented environments. Individual species showed different distributions and prevalence between sites and with increasing depth. Greatest differences were observed between the most-and leastdisturbed sites. Distinct sponge zonation patterns were evident at all sites sampled. Twenty-five species were considered dominant at all five sites with the remaining 48 species considered rare. Only four of the 25 most-dominant species occurred at the site experiencing the most turbulent flow conditions, whereas 12 species were found at the site of unidirectional fast flow. At sites of moderate to slight water movement and high sedimentation, between 18 and 24 of the most dominant species were present. Encrusting forms constituted high proportions of sponge communities at all five sites sampled (although consisting of different species). At sites of turbulent and unidirectional fast flow massive forms also dominated whereas at the least turbulent sites, where sedimentation was high, arborescent sponges were abundant. Few species showed exclusive distribution to a single depth and site, but there was some degree of correlation between species distributions and abiotic factors such as sedimentation rate and flow regimes. Sponge distributions and densities are discussed with respect to the suitability of species' morphologies to particular environments, intra-specific and inter-specific competition and physiological adaptations that enable them to survive in different habitats.

The influence of depth and substrate inclination on sessile assemblages in subantarctic rocky reefs (Magellan region)

“…Coralline and fleshy algae were more abundant on inclined surfaces, while invertebrate abundance (mainly as sheet-like growth forms) was higher on overhangs, which is consistent with previous studies from other latitudes (Logan et al 1984;Sebens 1985;Baynes 1999;Bell and Barnes 2000b;Miller and Etter 2011;Cárdenas et al 2012). Recently, Laudien and Orchard (2012) found distinct assemblages between inclinations in the shallows (until 30 m) but not in deeper zones (200 m) in Arctic sublittoral communities.…”

Reduced Diversity and High Sponge Abundance on a Sedimented Indo-Pacific Reef System: Implications for Future Changes in Environmental Quality

“…In a field experiment on a Mediterranean sponge species, exposure to sediment significantly reduced the longevity and success of young sponge recruits [72]. However, in contrast to these reports of the negative effects of sedimentation on sponges, a number of studies have reported high levels of sponge species richness and abundance in sedimented environments [24], [25], suggesting many species are tolerant to sedimentation. In addition, sedimentation has also been implicated in mediating competition effects between sponges and other benthic organisms, whereby negative effects of sediment on sponge competitors can enhance the success of sponges [24].…”

Rapid respiratory responses of the deep-water sponge Geodia barretti exposed to suspended sediments

“…Deep sea sponges in or near bottom-trawled areas are probably exposed to sediment plumes that can impact both their abundance and distribution, as has been observed for other sponge species (Bell & Barnes 2000, Carballo 2006, Bannister et al 2010. Sponges have an important role when it comes to benthic−pelagic coupling and recycling of nutrients (Pile & Young 2006, Yahel et al 2007, Maldonado et al 2012, and if that is disturbed a cascading ecological effect can be expected (Peterson et al 2006, Bell 2008.…”