Abstract
Population dynamics and life history traits of the giant limpet Scutellastra laticostata on intertidal limestone platforms at Rottnest Island, Western Australia, were recorded by interannual (January/February) monitoring of limpet density and size structure, and relocation of marked individuals, at 3 locations over periods of 13-16 yr between 1993 and 2020. Limpet densities ranged from 4 to 9 ind. m-2 on wave-swept seaward margins of platforms at 2 locations and on a rocky notch at the landward margin of the platform at a third. Juvenile recruits (25-55 mm shell length) were present each year, usually at low densities (1 m-2), but localized pulses of recruitment occurred in some years. Annual survival rates of marked limpets varied among sites and cohorts, ranging from 0.42 yr-1 at the notch to 0.79 and 0.87 yr-1 on the platforms. A mass mortality of limpets on the platforms occurred in 2003, likely mediated by thermal stress during daytime low tides, coincident with high air temperatures and calm seas. Juveniles grew rapidly to adult size within 2 yr. Asymptotic size (L, von Bertalanffy growth model) ranged from 89 to 97 mm, and maximum size from 100 to 113 mm, on platforms. Growth rate and maximum size were lower on the notch. Our empirical observations and simulation models suggest that these populations are relatively stable on a decadal time scale. The frequency and magnitude of recruitment pulses and high rate of adult survival provide considerable inertia, enabling persistence of these populations in the face of sporadic climatic extremes.
Original language | English |
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Pages (from-to) | 79-92 |
Number of pages | 14 |
Journal | Marine Ecology - Progress Series |
Volume | 646 |
DOIs | |
Publication status | Published - Jul 30 2020 |
Bibliographical note
Funding Information:Acknowledgements. We thank Jane Prince, Anna Metaxas and Michi Maier for help with field work; Matilda Murley, Jessica Hadlow and Katarina Doughty for measuring and photographing limpets at Nancy Cove in 2020; and Dan Reed for helping with data on Megathura crenulata. Funding for this work was provided by Research/Discovery Grants from the Natural Sciences and Engineering Research Council of Canada to R.E.S. and from the School of Biological Sciences, University of Western Australia, to R.B.
Publisher Copyright:
© 2020 Inter-Research. All rights reserved.
ASJC Scopus Subject Areas
- Ecology, Evolution, Behavior and Systematics
- Aquatic Science
- Ecology