Scientists analyzed effects from non-weathered source oil (collected directly over the Deepwater Horizon wellhead) and weathered slick oil (collected from surface skimming) on the microRNAs of mahi-mahi embryos.
The Smithsonian’s Ocean Portal published an article that gives readers a fascinating look at how scientists monitor the heartbeat, blood flow, and blood pressure of mahi-mahi before and after oil exposure.
Laboratory studies at the University of Miami suggest that exposure to Deepwater Horizon oil may have negatively affected heart function in mahi-mahi, reducing their ability to swim efficiently. Lela Schlenker is expanding that research to investigate if and how oil exposure alters the way mahi-mahi migrate and respond to predators and prey in the wild.
Researchers developed the first transcriptomic database for mahi-mahi embryos and larvae exposed to oil from the Deepwater Horizon incident. The team assembled over 60,000 transcripts, identified over 30,000 gene sequences, and observed 2,345 genes that differed significantly after exposure to weathered oil.
Data and pictures from before and after a disaster help us understand the impacts of an event; however, the “before” is not always available. Researchers with the RECOVER consortium have found through oil-exposure laboratory studies that the Deepwater Horizon incident may have negatively affected mahi-mahi’s heart function, vision, and swim performance.
Researchers conducted laboratory experiments on mahi-mahi embryos to determine the effects of ultraviolet radiation (UV) and oil co-exposure during different times in their development. The team observed that UV affected the success of mahi-mahi hatch in all exposure scenarios compared to controls but was highest (a 1.6- to 6-fold increase) when co-exposure occurred late in embryonic development.
The Smithsonian recently published an article about research, funded by the Gulf of Mexico Research Initiative (GoMRI), that investigates oil spill impacts on different life stages of mahi mahi. Highlights include what is involved in conducting this cutting-edge research, what is being discovered about mahi mahi that is not oil-spill related, and the multiple scientific perspectives that help develop a comprehensive understanding of these important fish.
Something very unusual—perhaps ominous—is happening with the dolphinfish population off the southeastern United States.
Studies that investigate the effects of oil exposure on developing fish are typically conducted at otherwise non-stressful ambient conditions, which may result in conservative impact estimates. Christina Pasparakis is studying the combined effects of oil exposure and other environmental stressors to create a more comprehensive assessment of Deepwater Horizon impacts.
Scientists used novel bioinformatics to investigate molecular-level changes over time and toxicity pathways in mahi-mahi embryos and larvae exposed to Deepwater Horizon oil. They observed that weathered oil induced more pronounced gene expression changes than a non-weathered source oil.