Supply-side control over the survivorship of Chthamalus spp. recruits in northern Baja California

ABSTRACT

The constant supply of larvae to coastal habitats is important for the persistence of populations and can vary depending on oceanic conditions that may affect physical transport processes. We evaluated the survivorship of Chthamalus recruits in Playa San Miguel, Baja California, for over a year to evaluate if the supply of new recruits was of greater importance than the post-recruitment factors of competition and predation in determining adult population size. We hypothesized that the number of Chthamalus recruits would predict the number of adults present and that predation and competition would not play a significant role in determining adult densities. Recruit density was a robust predictor of adult density despite the presence of weak density-dependent mortality. Neither predation nor competition significantly affected the survivorship of recruits and did not decouple the relationship between recruit and adult densities, suggesting that these post-recruitment controls did not play an important role in determining the population size of Chthamalus barnacles at this site. The data support the hypothesis that supply-side control is the primary factor structuring the population of Chthamalus in the intertidal community at Playa San Miguel.

RESPONSIBLE EDITOR:

• Dan Smale

KEYWORDS:

• Competition
• predation
• recruitment
• recruit-adult
• recruitment limitation
• supply-side ecology

Acknowledgements

Thank you to the ICE team (Interdisciplinary Coastal Ecology Team at CICESE) for their assistance with fieldwork.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by the Consejo Nacional de Ciencia y Tecnología project ‘LINK’ under grant no. 105622 and by the UCMEXUS-CONACYT project ‘FLOO, Fluxes Linking the Offshore and the Onshore’.