Mesoscale, finescale and microscale distribution of micro- and nanoplankton in the Irish Sea, with emphasis on ciliates and their prey

David J. S. Montagnes, Alex J. Poulton, T. M. Shammon

Research output: Contribution to journalArticle

50 Citations (Scopus)

Abstract

We examined the degree oF mesoscale (km), finescale (m), and microscale (cm) patchiness of ciliates and their prey in waters of varying hydrographic conditions. Samples were taken throughout the water column, along a transect across the Irish Sea (54°N), at scales ranging from 0.15 to 105 m. We examined physical, chemical, and biological characteristics. The eastern and western Irish Sea were stratified, with a pyenocline at ~20 to 30 m. The central waters were mixed and had adjacent frontal regions. Euphotic depth was ~20 to 35 m. Generally, the upper waters were nitrogen-limited, with elevated levels associated with frontal regions and deeper waters. Microphytoplankton exhibited fine-mesoscale patchiness: diatom numbers were low in stratified waters, with higher levels in mixed and frontal regions; dinoflagellates were abundant in subsurface waters near the fronts. Nanoflagellate numbers and biomass decreased with depth below the pyenocline, and exhibited microscale distribution in upper waters; these micropatches may provide increased food levels for ciliates. Microscale distribution of ciliates was rare and only occurred at mixed/frontal sites; finescale ciliate patches were a more prominent feature of the water column. These finescale patches can be composed of a variety of taxa but can also be virtually monospecific. Finescale patches may produce localised regions of high productivity that is available to fishes and copepods, but may also be a sink, as patches can be short-lived and thus unavailable to predators.

Original languageEnglish
Pages (from-to)167-179
Number of pages13
JournalMarine Biology
Volume134
Issue number1
DOIs
Publication statusPublished - Jun 1999

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Aquatic Science

Fingerprint Dive into the research topics of 'Mesoscale, finescale and microscale distribution of micro- and nanoplankton in the Irish Sea, with emphasis on ciliates and their prey'. Together they form a unique fingerprint.

  • Cite this