Abstract
Extreme climate events are becoming more frequent and intense under climate change, but their impacts on marine food webs are not well understood. In the North Atlantic, salinity anomalies over decadal timescales have been well studied, but extreme freshening has been observed in recent years at a magnitude far greater than prior measurements. Further, short-term fresh pulses and their ecological effects are poorly understood. We integrate recent monitoring data from the New York Bight with long-term datasets to document the ecosystem impacts of a short-term fresh pulse which influenced this region from September 2023 to September 2024. Mean surface salinity in this region was lower from February through August than in any other year of observation in a 30-year dataset, with salinity anomalies of -0.80 to -1.43 psu (mean − 1.13 psu). Profound ecosystem impacts of this event were observed throughout the food web. We observed aragonite saturation levels below 1, reflecting corrosive conditions for calcifying organisms. Elevated densities of key copepods occurred in spring and summer, while fish and invertebrates showed marked equatorward shifts in a reversal of recent poleward trends. Humpback whale body condition and residence time were unusually high. Anomalously high sightings rates of endangered North Atlantic right and sei whales occurred during a particularly fresh period in summer. Our findings address a gap in knowledge regarding the ecological impacts of fresh pulses, and portend widespread impacts of these events under continued climate change with implications for commercial and protected species.
Similar content being viewed by others
Effects of marine heat waves and cold spells on a polar shallow water ecosystem
Early life stage fish community structure and environmental drivers in offshore waters of Liaoning Province, Yellow Sea
Effect of host background and environmental conditions on disease susceptibility and mortality in the northern bay scallop, Argopecten irradians irradians
Acknowledgements
We thank Captains John Juntenun, Brian Gagliardi, Andrew Brosnan, Scott Convery, Chris Harter, Michael Mason, Chris Winsor, and David Bowman. We are grateful to Ellie Heywood, Baoshan Chen, Charlie Flagg, John Holden, Lawrence Bastinielli, Alex Borowicz, Audrey Calhoun, Matthew Fuirst, Madeline Hallet, Rachael Herman, Dallas Jordan, Kim Lato, Sarah Weisberg, Brandyn Lucca, Maha Alnajjar, Jessica Lopez, and Emma Pierce for their assistance with field work. We thank Tom Wilson, Alex Sneddon, Lucas Merlo, and Mark Wiggins for their assistance with carbonate chemistry instruments and glider deployments. We also thank the aerial observers and pilots from the NOAA Northeast Fisheries Science Center, NOAA Aircraft Operations Center, the Anderson Cabot Center for Ocean Life at the New England Aquarium, and Aspen Helicopters.
Funding
Funding for the NYB ocean monitoring program and data analysis was provided by New York State Environmental Protection Fund Ocean and Great Lakes, New York DEC.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing interests.
Additional information
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
Supplementary Material 1 (download DOCX )
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Reprints and permissions
About this article
Cite this article
Thorne, L.H., Nye, J.A., McSweeney, J.M. et al. Widespread ecosystem effects of an extreme fresh pulse event in a temperate marine ecosystem.
Sci Rep (2026). https://doi.org/10.1038/s41598-026-57921-4
Received:
Accepted:
Published:
DOI: https://doi.org/10.1038/s41598-026-57921-4
Keywords
- Extreme event
- Salinity
- Right whale
- Humpback whale
Calanus finmarchicus
- Aragonite
Source: Ecology - nature.com
