The longevity of marine species such as corals and gorgonians increases with the depth to which they live, according to a study conducted by the biologists at the Institute of Biodiversity Research of the University of Barcelona, the Institute of Marine Sciences of France, and the University of Colorado of the US.
The sessile species which live on the deepest seabeds have increased longevity
The study, which has been recently published in the journal Proceedings Of The Royal Society Of London B, details that deep marine ecosystems, of between 100 to 1,000 meters under the water, are dominated by long-living species that may live for hundreds or even thousands of years, while in not-so-deep waters, the same species only live a few dozen years.
The biologists Cristina Linares and Ignacio Montero Sierra (Spain), Joaquim Garrabou and Jean-Baptiste Ledoux (France), and Daniel F. Doak (USA) have studied, for the first time ever, the impact of different environmental factors (light, nutrients, temperature, physical disturbances, and human interventions) on the longevity of species that inhabit the deepest seabeds, such as corals, sponges, gorgonians, bivalves, and macroalgae.
This new study has a great relevance because until now the biological communities that have been studied by researchers are mostly located at a maximum depth of 40 meters, such as tropical reefs or algal communities.
Humans activities have a negative impact on the sessile species
In terms of biodiversity conservation, the authors warn of the effects of the human actions on the most vulnerable inhabitants of the seabed.
“The long-living species of the deeper habitats are especially sensitive to the impacts that increase the mortality of adult individuals,” Joaquim Garrabou has warned.
Consequently, the species of the deepest bottoms of the oceans and seas show a low resilience in the front of the environmental impact generated by human activities that can be highly destructive, such as trawling, for example.
This new study concluded that sessile species that live on the deepest seabeds possess an increased longevity because environmental factors are more stable in the deep and these species are more protected against environmental disturbances.