{"title":"Larvae in the Dark: Evidence of Diverse and Functionally Active Meroplankton Communities in an Arctic Fjord during the Polar Night.","authors":"Kharis Schrage, Kirstin S Meyer-Kaiser","doi":"10.1086/736174","DOIUrl":null,"url":null,"abstract":"<p><p>AbstractIn the high Arctic polar night, the sun remains below the horizon for a period ranging from several weeks to 6 months, providing insufficient solar radiation for photosynthesis to support the marine ecosystem. Despite this, recent studies have found evidence of active feeding, growth, and reproduction in multiple marine organisms during this period. Here, we describe the polar night diversity and activity levels of early pelagic life stages of benthic invertebrates (meroplankton), a group that has historically been largely overlooked. We assessed the taxa richness, reproductive and developmental biology, feeding, and competence to settle of meroplanktonic larvae in January 2023 in Kongsfjorden, Svalbard, using plankton tows, experiments, and DNA bar coding. Although meroplankton densities were lower than in other seasons, DNA bar coding allowed us to assess richness, which was much higher than other studies and seasons, with 48 unique taxa belonging to six phyla observed. Most were planktotrophic (feeding) larvae. Using laboratory assays and direct observations, we documented feeding in several of these planktotrophic larvae, including bryozoan cyphonautes, bivalve veligers, and an ophiuroid pluteus. We found numerous embryos, suggesting that several taxa are actively reproducing in the polar night. We observed settlement in two polychaete taxa in the laboratory, as well as metamorphosed echinoderms in our samples, showing competency to settle across phyla. Overall, we show that early life-history stages of a diverse range of benthic invertebrates are actively feeding and developing during the polar night. Further targeted research should focus on the polar night to better understand seasonal patterns in reproduction and development.</p>","PeriodicalId":55376,"journal":{"name":"Biological Bulletin","volume":"246 2-3","pages":"69-86"},"PeriodicalIF":2.1000,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biological Bulletin","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1086/736174","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/6/4 0:00:00","PubModel":"Epub","JCR":"Q2","JCRName":"BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
AbstractIn the high Arctic polar night, the sun remains below the horizon for a period ranging from several weeks to 6 months, providing insufficient solar radiation for photosynthesis to support the marine ecosystem. Despite this, recent studies have found evidence of active feeding, growth, and reproduction in multiple marine organisms during this period. Here, we describe the polar night diversity and activity levels of early pelagic life stages of benthic invertebrates (meroplankton), a group that has historically been largely overlooked. We assessed the taxa richness, reproductive and developmental biology, feeding, and competence to settle of meroplanktonic larvae in January 2023 in Kongsfjorden, Svalbard, using plankton tows, experiments, and DNA bar coding. Although meroplankton densities were lower than in other seasons, DNA bar coding allowed us to assess richness, which was much higher than other studies and seasons, with 48 unique taxa belonging to six phyla observed. Most were planktotrophic (feeding) larvae. Using laboratory assays and direct observations, we documented feeding in several of these planktotrophic larvae, including bryozoan cyphonautes, bivalve veligers, and an ophiuroid pluteus. We found numerous embryos, suggesting that several taxa are actively reproducing in the polar night. We observed settlement in two polychaete taxa in the laboratory, as well as metamorphosed echinoderms in our samples, showing competency to settle across phyla. Overall, we show that early life-history stages of a diverse range of benthic invertebrates are actively feeding and developing during the polar night. Further targeted research should focus on the polar night to better understand seasonal patterns in reproduction and development.
期刊介绍:
The Biological Bulletin disseminates novel scientific results in broadly related fields of biology in keeping with more than 100 years of a tradition of excellence. The Bulletin publishes outstanding original research with an overarching goal of explaining how organisms develop, function, and evolve in their natural environments. To that end, the journal publishes papers in the fields of Neurobiology and Behavior, Physiology and Biomechanics, Ecology and Evolution, Development and Reproduction, Cell Biology, Symbiosis and Systematics. The Bulletin emphasizes basic research on marine model systems but includes articles of an interdisciplinary nature when appropriate.