Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-27T08:22:57.190Z Has data issue: false hasContentIssue false

Thriving populations of the native macroalga Codium tomentosum on Guernsey rocky shores

Published online by Cambridge University Press:  12 October 2004

C.D. Trowbridge
Affiliation:
Hatfield Marine Science Center, Oregon State University, Newport, OR, USA Institute of Marine Sciences, University of Portsmouth, UK
W.F. Farnham
Affiliation:
Hatfield Marine Science Center, Oregon State University, Newport, OR, USA Institute of Marine Sciences, University of Portsmouth, UK
L.F. White
Affiliation:
Hatfield Marine Science Center, Oregon State University, Newport, OR, USA Institute of Marine Sciences, University of Portsmouth, UK

Abstract

Since the incursions of the introduced green macroalgae Codium fragile ssp. tomentosoides and ssp. atlanticum on European shores, the abundance and distribution of the native congeners C. tomentosum and C. vermilara have come under closer scrutiny. Hypotheses regarding the reported declines in the native(s) are largely speculative due to the paucity of quantitative information on the natives, the cryptic nature of the invaders and the unknown processes regulating Codium assemblages. As part of a field-based Codium study on north-eastern Atlantic shores, our surveys on Guernsey shores, Channel Islands, in September 2002 have revealed two unexpected and noteworthy results: (1) thriving populations of C. tomentosum are quite abundant on mid to low littoral shores; and (2) in marked contrast, sparse populations of C. fragile ssp. tomentosoides are restricted primarily to upper mid-littoral rock pools. Native Codium has not been displaced or eliminated from the southern end of the British Isles.

Type
Research Article
Copyright
2004 Marine Biological Association of the United Kingdom

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)