A team of researchers from the University of Maine Darling Marine Center in Walpole, non-profit Bigelow Laboratory for Ocean Sciences in East Boothbay, and the Maine Department of Marine Resources in West Boothbay Harbor recently published their research on the effects of ocean warming and acidification on gene expression in the earliest life stages of the American lobster.
The work was published in the scientific journal Ecology and Evolution with collaborators from the University of Prince Edward Island and Dalhousie University in Canada.
The team's experiments examined the gene regulatory response of postlarval lobsters to the separate and combined effects of warming and acidification anticipated by the end of the twenty-first century.
The team found that genes regulating a range of physiological functions, from those controlling shell formation to the immune response, are either up- or down-regulated. Importantly, they observed that the two stressors combined induced a greater gene regulatory response than either stressor alone.
The results from the study indicate that changes in gene expression of postlarval lobster may act as a mechanism to accommodate rapid changes in the ocean environment.
Recent UMaine graduate student Maura Niemisto, who led the study, noted that further study will be needed to determine how rapidly populations of the species may be able to adapt to changing conditions.
"To better understand how gene regulation in response to environmental changes functions within the species," said Niemisto, "we should look at subpopulations and multigenerational studies to determine the extent of species' capacity to respond to altered environmental conditions."
"[The] study reveals some of the hidden mechanisms species employ minute to minute and hour to hour at the cellular level to function normally in a variable environment," said Richard Wahle, research professor in UMaine's School of Marine Sciences and director of the Lobster Institute, as well as one of Niemisto's co-authors on the study. "We need to gain these insights as we take on the larger challenge of understanding how species adapt on the much larger time scale of decades."
According to the National Marine Fisheries Service, the American lobster fishery is the most valuable in North America. The species holds particular socioeconomic importance in the Gulf of Maine, where sea surface temperatures are increasing at a rate faster than most of the world's oceans and waters are more susceptible to higher rates of acidification.
The center of the American lobster range has been shifting northward in response to warming ocean temperatures. However, little is known about how the species will respond to the combined effects of increasing ocean temperatures and acidification.
The study is considered a first step in answering that question.
The species' earliest life stages are thought to be especially vulnerable to these climate related challenges.
