The open ocean is a harsh place for newborn fishes.
The open ocean is a harsh place for newborn fishes. From the minute larvae hatch from their eggs, their survival depends upon finding food and navigating ocean currents to their adult habitats — all while avoiding predators. This harrowing journey from egg to home has long been a mystery, until now.
An international team including scientists from the Arizona State University Center for Global Discovery and Conservation Science (GDCS), NOAA’s Pacific Islands Fisheries Science Center, and the University of Hawaii at Mānoa have discovered a diverse array of young marine animals finding refuge within so-called "surface slicks" in Hawaii. Surface slicks create a superhighway of nursery habitat for more than 100 species of commercially and ecologically important fishes, such as mahi-mahi, jacks and billfish. The study was published Feb. 4 in the journal Scientific Reports.
Surface slicks are naturally occurring ribbon-like bands of smooth water at the ocean surface and have long been recognized as an important part of the seascape. To unravel their secrets, the research team conducted more than 130 plankton net tows inside the surface slicks and surrounding waters along the leeward coast of the Island of Hawaii, while studying ocean properties. In these areas, they searched for larvae and other plankton that live close to the surface. They then combined those in-water surveys with a new satellite-based technique to map the location of the slicks. This technique involved using more than 100 shoebox-sized satellites, built and operated by GDCS partner Planet, to discern textural sea surface differences between surface slicks and regular seawater.
“In an earlier study, our surface slick mapping suggested strong along-coast connectivity of ocean habitats. In our latest study reported here, we populated those satellite-based slick maps with the billions of animals, organic debris and microplastics that make up the slicks," said Greg Asner, GDCS director and co-author of the study.
Read more at Arizona State University
Image: Composite image showing just a small portion of the remarkable diversity of larval and juvenile fishes and invertebrates found living in surface slick nurseries along West Hawaii Island. (Credit: Larval photos: Jonathan Whitney (NOAA Fisheries), Slick photo: Joey Lecky (NOAA Fisheries).)
