Sediment stirred up from fishing activity has a detrimental effect on reef-building sea sponges in northern British Columbia, according to a new study by University of Alberta biologists.
Sediment stirred up from fishing activity has a detrimental effect on reef-building sea sponges in northern British Columbia, according to a new study by University of Alberta biologists.
The sediment is kicked up during human activities such as bottom trawling, where a weighted net is dragged across the seafloor. It includes organic matter as well as clay and silt, which can smother sponges from the outside or, if taken into their filtration system, clog them.
“If sponges are clogged, they can die, and if sponges die, then the other animals that use the sponges as homes or as food are in trouble as well,” explained U of A marine biologist Sally Leys, who was lead author of the study.
“The finer the particle, the worse for the sponge. Even a week of not filtering could mean the death of the reef.”
A critical part of the marine ecosystem, sponges act as a filtration system for the sea, consuming bacteria and returning nutrients to the waters that help sustain plankton and fish. The sponges also provide habitat in the form of reefs, which provide homes to countless marine organisms.
Continue reading at University of Alberta.
Image via Sally Leys/CSSF-ROPOS/DFO Canada.
