Answers are grounded in this paper and cite their sources.
A. J. Southward, D. J. Crisp, Recent Changes in the Distribution of the Intertidal Barnacles Chthamalus stellatus Poli and Balanus balanoides L. in the British Isles, Journal of Animal Ecology, Vol. 23, No. 1 (May, 1954), pp. 163-177
No takes yet. Share an insight, caveat, or question.
Southward et al. (1954) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: