Effects of a tropical cyclone on a pelagic ecosystem from the physical environment to top predators

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 484:1-16 (2013) - DOI: https://doi.org/10.3354/meps10378 FEATURE ARTICLEEffects of a tropical cyclone on a pelagic ecosystem from the physical environment to top predators Paul C. Fiedler1,*, Jessica V. Redfern1, Joel Van Noord1,2, Candice Hall1,3, Robert L. Pitman1, Lisa T. Ballance1 1Marine Mammal & Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 8901 La Jolla Shores Drive, La Jolla, California 92037, USA 2California Wetfish Producers Association, PO Box 1951, Buellton, California 93427, USA 3Ocean Associates, Inc., 4007 N. Abingdon Street, Arlington, Virginia 22207, USA *Email: Paul.Fiedler@noaa.gov ABSTRACT: Tropical cyclones are environmental disturbances that may have important effects on open-ocean ecosystem structure and function, but their overall impact has rarely been assessed. The Stenella Abundance Research Line Transect and Ecosystem (STARLITE) survey, in August-November 2007, investigated spatial and temporal ecosystem variability in the eastern tropical Pacific Ocean off southwestern Mexico. Oceanographic, plankton, flyingfish, seabird, and cetacean sampling was conducted along eight 170 km transect lines, each of which were surveyed on 2 consecutive days at ~3 wk intervals. Tropical storm Kiko passed though the study area on 15-17 October and forced changes in the physical environment and in the ecosystem, from plankton to top predators. Kiko mixed water from beneath the strong, shallow thermocline to the surface. As a result, surface temperature decreased by 0.6°C, the thermocline and chlorophyll maximum layer shoaled by 10-20 m, stratification decreased by 27%, and chlorophyll increased by 33% at the surface and 35% over the euphotic zone. These changes persisted for at least 4 wk. Zooplankton biomass increased by 59% about 3 wk after the phytoplankton increase. Changes in the stomach fullness and diet composition of planktivorous flyingfish were consistent with the increase in zooplankton biomass. Among top predators, the sighting rate of dolphins declined, while the response of seabirds varied by species and was confounded by seasonal migration patterns. Tropical cyclones are a recurrent disturbance in this region. They initiate a bottom-up forcing of the ecosystem, creating persistent patches of higher primary and secondary production, and may be regarded as a disturbance regime. KEY WORDS: Pelagic ecosystem · Eastern tropical Pacific · Top predator · Storm · Disturbance · Bottom- up forcing Full text in pdf format Information about this Feature Article NextCite this article as: Fiedler PC, Redfern JV, Van Noord J, Hall C, Pitman RL, Ballance LT (2013) Effects of a tropical cyclone on a pelagic ecosystem from the physical environment to top predators. Mar Ecol Prog Ser 484:1-16. https://doi.org/10.3354/meps10378Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 484. Online publication date: June 12, 2013 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2013 Inter-Research.