Implications of habitat-specific growth and physiological condition on juvenile crab population structure
Valter Amaral A B D , Henrique N. Cabral C and José Paula AA Laboratório Marítimo da Guia, Faculdade de Ciências da Universidade de Lisboa, Avenida Nossa Senhora do Cabo 939, 2750-374 Cascais, Portugal.
B Marine Biological Association of the UK, Citadel Hill, Plymouth, PL1 2PB, UK.
C Instituto de Oceanografia, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
D Corresponding author. Email. vlamaral@fc.ul.pt
Marine and Freshwater Research 59(8) 726-734 https://doi.org/10.1071/MF08006
Submitted: 10 January 2008 Accepted: 14 June 2008 Published: 22 August 2008
Abstract
Post-settlement processes can regulate the size and structure of marine invertebrate and fish populations. Faster growth and better physiological condition generally increase the survival potential of early juveniles, being usually associated with structurally complex habitats. Successive cohorts of early juvenile Carcinus maenas were followed in sandy and seagrass (Zostera noltii) habitats in the Mira Estuary, Portugal, to estimate growth and physiological condition (evaluated by RNA/DNA ratio) of juvenile populations. Mean cohort growth was similar in both habitats. However, in the sandy habitat, population size structure progressed to cohorts of larger carapace width (CW) and the RNA/DNA ratio was always higher than in the Z. noltii habitat. In this habitat, cohorts of low CW prevailed throughout and RNA/DNA ratio only increased after ~5.0 mm CW. Higher densities characterising seagrass areas may result in higher competition for resources, limiting growth and condition and leading to dispersal to less populated habitats. Larger juveniles had the best physiological condition, especially early in the season. Seagrass habitats do not necessarily yield enhanced growth rates and physiological condition of early juvenile crabs in relation to sandy areas. Knowledge of such trends is vital to understand distribution and abundance patterns of fish and marine invertebrate populations.
Additional keywords: estuarine, habitat quality, NanoDrop, nucleic acids, population dynamics.
Acknowledgements
We are in debt to V. F. Fonseca for her help with nucleic acids analyses. We thank Professor Andrew Boulton and two anonymous referees for critical comments that greatly improved the manuscript. V.A. acknowledges a PhD grant (SFRH/BD/10471/2002) funded by Fundação para a Ciência e a Tecnologia. All work complied with Portuguese government laws.
Amaral, V. , and Paula, J. (2007). Carcinus maenas (Crustacea: Brachyura): influence of artificial substrate type and patchiness on estimation of megalopae settlement. Journal of Experimental Marine Biology and Ecology 346, 21–27.
| Crossref | GoogleScholarGoogle Scholar |
Anger, K. , and Hirche, H. J. (1990). Nucleic acids and growth of larval and early juvenile spider crab, Hyas araneus. Marine Biology (Berlin) 105, 403–411.
| Crossref | GoogleScholarGoogle Scholar |
Buckley, L. , Caldarone, E. , and Ong, T. (1999). RNA-DNA ratio and other nucleic acid-based indicators for growth and condition of marine fishes. Hydrobiologia 401, 265–277.
| Crossref | GoogleScholarGoogle Scholar |
Caley, M. J. , Carr, M. H. , Hixon, M. A. , Hughes, T. P. , Jones, G. P. , and Menge, B. A. (1996). Recruitment and the local dynamics of open marine populations. Annual Review of Ecology and Systematics 27, 477–500.
| Crossref | GoogleScholarGoogle Scholar |
Feldman, K. L. , Armstrong, D. A. , Eggleston, D. B. , and Dumbauld, B. R. (1997). Effects of substrate selection and post-settlement survival on recruitment success of the thalassinidean shrimp Neotrypaea californiensis to intertidal shell and mud habitats. Marine Ecology Progress Series 150, 121–136.
| Crossref | GoogleScholarGoogle Scholar |
Queiroga, H. (1998). Vertical migration and selective tidal stream transport in the megalopa of the crab Carcinus maenas. Hydrobiologia 375–376, 137–149.
| Crossref | GoogleScholarGoogle Scholar |
Queiroga, H. , Almeida, M. J. , Alpuim, T. , Flores, A. A. V. , and Francisco, S. , et al. (2006). Tide and wind control of megalopal supply to estuarine crab populations on the Portuguese west coast. Marine Ecology Progress Series 307, 21–36.
| Crossref | GoogleScholarGoogle Scholar |
Reid, J. M. , Bignal, E. M. , Bignal, S. , McCracken, D. I. , and Monaghan, P. (2006). Spatial variation in demography and population growth rate: the importance of natal location. Journal of Animal Ecology 75, 1201–1211.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Roughgarden, J. , Gaines, S. , and Possingham, H. (1988). Recruitment dynamics in complex life cycles. Science 241, 1460–1466.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Silva, I. C. , Dinis, A. M. , Francisco, S. M. , Flores, A. A. V. , and Paula, J. (2006). Longitudinal distribution and lateral pattern of megalopal settlement and juvenile recruitment of Carcinus maenas (L.) (Brachyura, Portunidae) in the Mira River Estuary, Portugal. Estuarine, Coastal and Shelf Science 69, 179–188.
| Crossref | GoogleScholarGoogle Scholar |
Suthers, I. M. (1998). Bigger? Fatter? Or is faster growth better? Considerations on condition in larval and juvenile coral-reef fish. Australian Journal of Ecology 23, 265–273.
| Crossref | GoogleScholarGoogle Scholar |
Thorson, G. (1950). Reproductive and larval ecology of marine bottom invertebrates. Biological Reviews of the Cambridge Philosophical Society 25, 1–45.
| Crossref | GoogleScholarGoogle Scholar |
Wagner, M. M. , Campbell, R. G. , Boudreau, C. A. , and Durbin, E. G. (2001). Nucleic acids and growth of Calanus finmarchicus in the laboratory under different food and temperature conditions. Marine Ecology Progress Series 221, 185–197.
| Crossref | GoogleScholarGoogle Scholar |
Wang, S. Y. , and Stickle, W. B. (1986). Changes in nucleic acid concentration with starvation in the blue crab Callinectes sapidus Rathbun. Journal of Crustacean Biology 6, 49–56.
| Crossref | GoogleScholarGoogle Scholar |
Werner, E. E. , and Gilliam, J. F. (1984). The ontogenetic niche and species interactions in size-structured populations. Annual Review of Ecology and Systematics 15, 393–425.
| Crossref | GoogleScholarGoogle Scholar |
Wright, D. A. , and Hetzel, E. W. (1985). Use of RNA:DNA ratios as an indicator of nutritional stress in the American oyster Crassostrea virginica. Marine Ecology Progress Series 25, 199–206.
| Crossref | GoogleScholarGoogle Scholar |