A comparison of temporal turnover of species from benthic cnidarian assemblages in tropical and subtropical harbours

Abstract

An important component of species diversity which has recently received significant attention is the change in species composition across space, or beta diversity. Temporal turnover of species is an equally important component of species diversity, which can by itself account for diversity patterns, but has received much less attention, especially in marine communities. Indeed, patterns of diversity of marine epifaunal assemblages may be better understood through the study of variability in richness and composition of recruits that colonize and survive long enough to start a population, but before species interactions mask the diversity initially settled. Here we document temporal patterns in richness and composition of recruits of a speciose benthic cnidarian assemblage, contrasting a tropical and a subtropical site to evaluate simple predictions about latitudinal diversity and richness stability. Recruitment variation was quantified during five three-month periods at two harbour areas (Pecém at 3°32′S and Ilhabela at 23°46′S) in Brazil separated by 20° latitude. Results show that: (1) species richness of benthic cnidarian assemblages was higher at the more tropical location, as expected from general patterns in marine species global distribution; (2) contrary to the expectation of a negative association between richness and species turnover, temporal turnover of species was similar at both sites, although more seasonal at the higher latitude site; and (3) species temporal persistence was greater at the subtropical site. Results are discussed in the context of how different environments and different regional richness may influence temporal patterns in species turnover and local richness, and how this may vary across latitudes.

Key words:

• Latitude
• sampling
• species richness
• species temporal distribution
• temporal turnover

Acknowledgements

We thank Alvaro Migotto and Centro de Biologia Marinha (CEBIMar) of the Universidade de São Paulo for providing laboratory facilities during field studies, the Ilhabela Yacht Club and the Pecém Harbor for allowing sampling on the piers, Rosana Rocha and Tito Lotufo for their contributions throughout the study, colleagues in the Marine Evolution Laboratory, USP, for their support and suggestions, James Roper for language assistance, and three anonymous reviewers for their valuable suggestions.

Supplementary material

(Tables SI–SIII)

The supplementary material for this article is available via the Supplemental tab of the article's online page at http://dx.doi.org/10.1080/17451000.2014.955804

Editorial responsibility: David McKinnon

Additional information

Funding

MOF held a MSc scholarship from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and PhD scholarships from CNPq (Consellho Nacional de Desenvolvimento Científico e Tecnológico) and FAPESP. SAN is grateful for support from FAPESP through a visiting science grant (#2012/0519-3) which made this collaboration possible. ACM was supported by FAPESP, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), and CNPq. This study was funded by the project CAPES PROCAD and PROTAX, FAPESP 2010/52324-6, 2011/50242-5, 2013/50484-4, and CNPq 563106/2010-7, 458555/2013-4, 305805/2013-4. This publication is a contribution of NP-BioMar, USP.