Warming off southwestern Japan linked to distributional shifts of subtidal canopy‐forming seaweeds
Open Access
- 12 October 2012
- journal article
- research article
- Published by Wiley in Ecology and Evolution
- Vol. 2 (11), 2854-2865
- https://doi.org/10.1002/ece3.391
Abstract
To assess distributional shifts of species in response to recent warming, historical distribution records are the most requisite information. The surface seawater temperature (SST) of Kochi Prefecture, southwestern Japan on the western North Pacific, has significantly risen, being warmed by the Kuroshio Current. Past distributional records of subtidal canopy‐forming seaweeds (Laminariales and Fucales) exist at about 10‐year intervals from the 1970s, along with detailed SST datasets at several sites along Kochi's >700 km coastline. In order to provide a clear picture of distributional shifts of coastal marine organisms in response to warming SST, we observed the present distribution of seaweeds and analyzed the SST datasets to estimate spatiotemporal SST trends in this coastal region. We present a large increase of 0.3°C/decade in the annual mean SST of this area over the past 40 years. Furthermore, a comparison of the previous and present distributions clearly showed the contraction of temperate species' distributional ranges and expansion of tropical species' distributional ranges in the seaweeds. Although the main temperate kelp Ecklonia (Laminariales) had expanded their distribution during periods of cooler SST, they subsequently declined as the SST warmed. Notably, the warmest SST of the 1997–98 El Niño Southern Oscillation event was the most likely cause of a widespread destruction of the kelp populations; no recovery was found even in the present survey at the formerly habitable sites where warm SSTs have been maintained. Temperate Sargassum spp. (Fucales) that dominated widely in the 1970s also declined in accordance with recent warming SSTs. In contrast, the tropical species, S. ilicifolium, has gradually expanded its distribution to become the most conspicuously dominant among the present observations. Thermal gradients, mainly driven by the warming Kuroshio Current, are presented as an explanation for the successive changes in both temperate and tropical species' distributions.Keywords
This publication has 36 references indexed in Scilit:
- Seaweed assemblage changes in the eastern Cantabrian Sea and their potential relationship to climate changeEstuarine, Coastal and Shelf Science, 2012
- Impact of oceanic warming on the distribution of seaweeds in polar and cold-temperate watersBotanica Marina, 2009
- Ecological and Evolutionary Responses to Recent Climate ChangeAnnual Review of Ecology, Evolution, and Systematics, 2006
- The impacts of climate change in coastal marine systemsEcology Letters, 2006
- Responses of the Kuroshio and the Kuroshio Extension to global warming in a high‐resolution climate modelGeophysical Research Letters, 2005
- Giant kelp (Macrocystis pyrifera) survival in deep water (25–40 m) during El Niño of 1997–1998 in Baja California, MexicoBotanica Marina, 2004
- Estimating scale-dependency in disturbance impacts: El Ni os and giant kelp forests in the northeast PacificOecologia, 2003
- Ecological responses to recent climate changeNature, 2002
- North Pacific Atmospheric and SST Anomalies in 1997: Links to ENSO?Fisheries Oceanography, 2001
- GIANT KELP (MACROCYSTIS PYRIFERA, PHAEOPHYCEAE) RECRUITMENT NEAR ITS SOUTHERN LIMIT IN BAJA CALIFORNIA AFTER MASS DISAPPEARANCE DURING ENSO 1997–1998Journal of Phycology, 1999