Description
Summary:Progress Code: completed Statement: Values provided in temporal and spatial coverage are approximate only. This record has been updated by staff at the Australian Antarctic Data Centre (rather than the listed investigator), and therefore it's accuracy and quality cannot be guaranteed. See the final report at the URL below for full and accurate information. Metadata record for data from ASAC Project 2300 See the link below for public details on this project. --- Public Summary from Project --- Antarctic reefs, like their tropical counterparts, harbour a high diversity of animal life. For the first time we will determine how global warming will affect food availability to the animals which comprise the structural components of the reefs. Ultimately, we wish to predict the cascading effect through the community as one component changes. With the confirmation that sponges in Antarctic waters graze on ultraplankton there is now a global overview that sponges are the primary benthic organism that is responsible for linking the pelagic microbial food web to the benthos. Like other shallow water demosponges, sponges in Antarctica are omnivorous sponges that graze nonselectively, consuming both heterotrophic and phototrophic organisms. Retention efficiencies of ultraplankton are similar to other sponges measured using similar techniques from shallow water to the deep sea, the tropics to boreal waters. The large amounts of water processed by these benthic suspension feeders and their diet places these sponges squarely within the functional group of organisms that link the pelagic microbial food web to the benthos. The number of macroinvertebrates that have been shown to side- step the microbial loop and directly utilize the base of the microbial food web as a primary food source is ever growing and currently includes demosponges, ascidians, soft corals, and bivalves. Dense macroinvertebrate communities dominated by demosponges and corals in shallow water have been shown to remove as much as 90% of the ultraplankton ...