University of Hawaiʻi at Mānoa School of Ocean and Earth Science and Technology (SOEST) researchers found that human-induced environmental stressors have a large effect on the genetic composition of coral reef populations in Hawaiʻi. According to a recent study, they confirmed that there is an ongoing loss of sensitive genotypes in nearshore coral populations due to stressors resulting from poor land-use practices and coastal pollution. This reduced genetic diversity compromises reef resilience.
The study identified closer genetic relationships between nearshore corals in Maunalua Bay, Oʻahu and those from sites on West Maui, than to corals from the same islands, but further offshore. This pattern can be described as isolation by environment in contrast to isolation by distance. This is an adaptive response by the corals to watershed discharges that contain sediment and pollutants from land.
“While the results were not surprising, they clearly demonstrate the critical need to control local sources of stress immediately while concurrently addressing the root causes of global climate change,” said Robert Richmond, UH Mānoa research professor and director of the Kewalo Marine Laboratory and co-author of the study. “Additionally, this innovative science shows the need to track biodiversity at multiple levels.”
This research provides valuable information to coral reef managers in Hawaiʻi and around the world who are developing approaches and implementation plans to enhance coral reef resilience and recovery through reef restoration and stressor reduction.
“This study shows the value of applying molecular tools to ecological studies supporting coral reef management,” stated Kaho Tisthammer, lead researcher on this paper.
Read more of the story on SOEST’s website.
—By Marcie Grabowski