Marine Biology

, Volume 147, Issue 6, pp 1343–1352 | Cite as

The abundance and life histories of terrestrial isopods in a salt marsh of the Ria Formosa lagoon system, southern Portugal

  • N. DiasEmail author
  • M. Sprung
  • M. Hassall
Research Article


Four species of isopod characteristic of salt marsh habitats, Tylos ponticus, Porcellio lamellatus, Halophiloscia couchii and Armadillidium album coexist in the upper reaches of the Ria Formosa lagoon salt marsh system in southern Portugal. In this locality, T. ponticus is the most abundant of the four species with mean annual densities of 2,950 m−2 and a peak density of 10,387 m−2 in July 1998 which is very much higher than what has previously been recorded for any isopod in any habitat. The mean annual densities for the other species were lower: P. lamellatus 36 m−2, A. album 19 m−2 and H. couchii 3 m−2, indicating a less significant role in this ecosystem. Tylos ponticus and A. album started to breed on May, 24 and 12 months after release from the marsupium, respectively, where as other species start to breed in March, 12 months after their release from the marsupium. Tylos ponticus has a relative growth rate (RGR) of 0.23 between release from the marsupium and time of first breeding in July of its second year and breeds at a mature mass of 3.6 mg AFDM whereas the other three species mature after 10–12 months, have more than double this RGR but because of the shorter pre-reproductive period breed at masses of 1.8 mg AFDM for P. lamellatus, 1.0 mg AFDM for H. couchii, and 1.1 mg AFDM for A. album, respectively. The mass specific fecundity of all three of the less abundant species was higher than that of T. ponticus but the offspring of T. ponticus were ten times heavier than those of the next largest species, P. lammellatus. The difference in abundances between the species is interpreted as being due to the larger mass of the offspring of the most successful species. This larger mass confers an adaptive advantage due to larger size being associated with reduced juvenile mortality for isopods under abiotically stressful conditions.


Salt Marsh Relative Growth Rate Brood Size Offspring Size High Tide Level 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank Dr. H. Schmalfuss (Staatliches Museum für Naturkunde, Stuttgart, Germany) and Dr. D. Caruso (University of Catania, Catania, Italy) for confirming the identification of isopods. Dr. H. Schmalfuss also kindly gave advice on the phylogeny and evolution of terrestrial isopods. The first author acknowledges financial support by the Fundação para a Ciência e Tecnologia (grant PRAXIS XXI/BD/11039/97). The experiments comply with the current national laws.


  1. Adam P (1990) Salt marsh ecology. Cambridge University Press, CambridgeGoogle Scholar
  2. Al-Dabbagh KY, Block W (1981) Population ecology of a terrestrial isopod in two breckland grass heaths. J Anim Ecol 50:61–77CrossRefGoogle Scholar
  3. Bhattacharya CG (1967) A simple method of resolution of a distribution into Gaussian components. Biometrics 23:115–135PubMedCrossRefGoogle Scholar
  4. Brody MS, Lawlor LR (1983) Adaptive variation in offspring size in the terrestrial isopod, Armadillidium vulgare. Oecologia 61:55–59CrossRefGoogle Scholar
  5. Chapman VJ (1992) Ecosystems of the World—wet coastal ecosystems, vol I, 2nd edn. Elsevier Science Publishers, AmsterdamGoogle Scholar
  6. Davis RC (1984) Effects of weather and habitat structure on the population dynamics of isopods in a dune grassland. Oikos 42:387–395CrossRefGoogle Scholar
  7. Davis RC, Sutton SL (1978) A comparative study of changes in biomass of isopods inhabiting dune grassland. Sci Proc R Dublin Soc A 6(11):223–233Google Scholar
  8. Dias N, Hassall M (2005) Food, feeding and growth rates of pericarid macro-decomposers in a Ria Formosa salt marsh, Southern Portugal. J Exp Mar Biol Ecol (in press)Google Scholar
  9. Dias N, Sprung M (2003) Population dynamics and production of the isopod Tylos ponticus in a Ria Formosa salt marsh (South Portugal). Crust Monogr 2:133–149Google Scholar
  10. Dias N, Hassall M, Sprung M (2005) Contribution of peracarid macro-decomposers to organic matter degradation in a salt marsh of the Ria Formosa lagoon (Southern Portugal). Eur J Soil Biol (in press)Google Scholar
  11. Edney EB (1954) Woodlice and the land habitat. Biol Rev 29:185–219CrossRefGoogle Scholar
  12. van Emden HF (1969) Plant resistance to Myzus persicae induced by a plant regulator and measured by aphid relative growth rate. Entomol Exp Appl 12:125–131CrossRefGoogle Scholar
  13. Erhard F (1998) Phylogenetic relationships within the Oniscidea (Crustacea, Isopoda). Isr J Zool 44:303–309Google Scholar
  14. Falcão M, Vale C (1990) Study of the Ria Formosa ecosystem; benthic nutrient remineralization and tidal variability of nutrients in the water. Hydrobiologia 207:137–146CrossRefGoogle Scholar
  15. Farkas S (1998) Population dynamics, spatial distribution, and sex ratio of Trachelipus rathkei Brandt (Isopoda: Oniscidea) in a wetland forest by the Drava river. Isr J Zool 44:323–331Google Scholar
  16. Ford NB, Siegel RA (1989) Phenotypic plasticity in reproductive traits: evidence from a viviparous snake. Ecology 70:1768–1774CrossRefGoogle Scholar
  17. Friedman GM, Sanders JE (1978) Principles of sedimentology. Wiley, New YorkCrossRefGoogle Scholar
  18. Gottard K, Nylin S (1995) Adaptive plasticity as an adaptation: a selective review of plasticity and life history. Oikos 74:3–17CrossRefGoogle Scholar
  19. Hassall M, Dangerfield JM (1989) Inter-specific competition and the relative abundance of grassland isopods. Monit Zool Ital (N.S.) Monogr Ser 4:379–397Google Scholar
  20. Hassall M, Dangerfield JM (1990) Density-dependent processes in the population dynamics of Armadillidium vulgare (Isopoda: Oniscidea). J Anim Ecol 59:941–958CrossRefGoogle Scholar
  21. Hassall M, Dangerfield JM (1997) The population dynamics of a woodlouse, Armadillidium vulgare: an example of biotic compensatory mechanisms amongst terrestrial macrodecomposers? Pedobiologia 41:342–360Google Scholar
  22. Hassall M, Davis RC (1991) Selection pressures acting on life histories of grassland isopods. In: Proceedings of the IVth European Congress of Entomology, pp 723–732Google Scholar
  23. Hassall M, Heldon A, Goldston A, Grant A (2005) Ecotypic differentiation and phenotypic plasticity in reproductive traits of Armadillidium vulgare (Isopoda: Oniscidae). Oecologia 143:51–60PubMedCrossRefGoogle Scholar
  24. Hopkin S (1991) A key to the woodlice of Britain and Ireland. Field Stud 7:599–650Google Scholar
  25. Hornung E (1989) Population dynamics and spatial distribution of Trachelipus nodulosus (C.L. Koch, 1838) (Crustacea Isopoda) in a sandy grassland. Monit Zool Ital (N.S.) Monogr Ser 4:399–409Google Scholar
  26. Hornung R (2005) Review of the evolutionary aspects of oniscid (Isopoda) reproductive strategies. Acta Biol Bernodis (in press)Google Scholar
  27. Hornung E, Warburg MR (1995) Seasonal changes in the distribution and abundance of isopod species in different habitats within the Mediterranean region of Northern Israel. Acta Oecologica 16(4):431–445Google Scholar
  28. Kneib RT (1984) Patterns of invertebrate distribution and abundance in the intertidal salt marsh: causes and questions. Estuaries 7(4A):392–412CrossRefGoogle Scholar
  29. Krebs CJ (1998) Ecological methodology. Addison Wesley, Menlo ParkGoogle Scholar
  30. Kreeger DA, Newell RIE (2000) Trophic complexity between producers and invertebrate consumers in salt marshes. In: Weinstein MP, Kreeger DA (eds) Concepts and controversies in tidal marsh ecology. Kluwer, Dordrecht, pp 187–220Google Scholar
  31. Lee KE, Wood TG (1971) Termites and soils. Academic, LondonGoogle Scholar
  32. Levin LA, Talley TS (2000) Influences of vegetation and abiotic environmental factors on salt marsh invertebrates. In: Weinstein MP, Kreeger DA (eds) Concepts and controversies in tidal marsh ecology. Kluwer, Dordrecht, pp 661–707Google Scholar
  33. McLachlan A, Sieben PR (1991) Growth and production of Tylos capensis Krauss, 1843 (Isopoda). Crustaceana 61(1):43–48CrossRefGoogle Scholar
  34. Messina FJ, Fox CW (2001) Offspring size and number. In: Fox CW, Roff DA, Fairbairn DT (eds) Evolutionary ecology: concepts and case studies. Oxford University Press, Oxford, pp 113–127Google Scholar
  35. Montague CL, Bunker SM, Haines EB, Pace ML, Wetzel RL (1981) Aquatic macroconsumers. In: Pomeroy LR, Wiegert RG (eds) The ecology of a salt marsh. Springer, Berlin Heidelberg New York, pp 69–86Google Scholar
  36. Odum WE (1970) Utilization of the direct grazing and plant detritus food chains by the stiped mullet, Mugil cephalus. In: Steele JH (ed) Marine food chains. University of California, Berkeley, pp 222–240Google Scholar
  37. Paris OH (1963) The ecology of Armadillidium vulgare in California grassland: food, enemies and weather. Ecol Monogr 33(1):1–22CrossRefGoogle Scholar
  38. Riedl R (1986) Fauna y Flora del Mar Mediterráneo. Ediciones Omega, BarcelonaGoogle Scholar
  39. Roff DA (2002) Life history evolution. Sinauer Associates Inc., SunderlandGoogle Scholar
  40. Rushton SP, Hassall M (1987) Effects of food quality on isopod populations dynamics. Funct Ecol 1:359–367CrossRefGoogle Scholar
  41. Schmalfuss H (1989) Phylogenetics in Oniscidea. Monit Zool Ital (N.S.) Monogr Ser 4:3–27Google Scholar
  42. Schmalfuss H (1998) Evolutionary strategies of the antennae in terrestrial isopods. J Crust Biol 18(1):10–24CrossRefGoogle Scholar
  43. Shashak M, Yair A (1984) Population dynamics and role of Hemilepistus reaumuri (Audouin and Savigny) in a desert ecosystem. Symp Zool Soc Lond 53:295–314Google Scholar
  44. Sibly RM, Calow P (1985) Classification of habitats by selection pressures: a synthesis of life-cycle and r/K theory. In: Sibley RM, Smith RH (eds) Behavioural ecology. Ecological consequences of adaptive behaviour. 25th Symposium of the British Ecological Society, Reading 1984. Blackwell, Oxford, pp 75–90Google Scholar
  45. Southwood TRE (1988) Tactics, strategies and templates. Oikos 52:3–18CrossRefGoogle Scholar
  46. Sprung M, Machado M (2000) Distinct life histories of peracarid crustaceans in a Ria Formosa salt marsh (S. Portugal). Wetl Ecol Manage 8:105–115CrossRefGoogle Scholar
  47. Stearns SC (1992) The evolution of life histories. Oxford University Press, OxfordGoogle Scholar
  48. Sunderland KD, Hassall M, Sutton SL (1976) The population dynamics of Philoscia muscorum (Crustacea: Oniscidea) in a dune grassland ecosystem. J Anim Ecol 45:732–735Google Scholar
  49. Sutton SL (1968) The population dynamics of Trichoniscus pusillus and Philoscia muscorum (Crustacea, Oniscoidea) in limestone grassland. J Anim Ecol 37:425–444CrossRefGoogle Scholar
  50. Sutton SL, Hassall M, Willows R, Davis RC, Grundy A, Sunderland KD (1984) Life histories of terrestrial isopods: a study of intra- and interspecific variation. Symp Zool Soc Lond 53:269–294Google Scholar
  51. Teal JM (1962) Energy flow in the salt marsh ecosystem of Georgia. Ecology 43(4):614–624CrossRefGoogle Scholar
  52. Vader W, Wolf L (1988) Biotope and biology of Armadillidium album Dollfuss, a terrestrial isopod of sandy beaches, in the SW Netherlands. Neth J Sea Res 22(2):175–183CrossRefGoogle Scholar
  53. Vernberg FJ (1993) Salt-marsh processes: a review. Environ Toxicol Chem 12:2167–2193CrossRefGoogle Scholar
  54. Warburg MR, Linsenmair KE, Bercovitz K (1984) The effect of climate on the distribution and abundance of isopods. Symp Zool Soc Lond 53:339–367Google Scholar
  55. Zimmer M (2003) Habitat and resource use by terrestrial isopods (Isopoda, Oniscidea). In: Sfenthourakis S, Araújo PB, Hornung E, Schmalfuss H, Taiti S, Szlavecz S (eds) The biology of terrestrial isopods, V. Proceedings of the 5th international symposium on the biology of terrestrial isopods. Crustaceana Monographs 2:243–261Google Scholar
  56. Zimmer M, Pennings SC, Buck TL, Carefoot TH (2002) Species-specific patterns of litter processing by terrestrial isopods (Isopoda: Oniscidea) in high intertidal salt marshes and coastal forests. Funct Ecol 16:596–607CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Faculdade de Ciências do Mar e do AmbienteUniversidade do AlgarveFaroPortugal
  2. 2.Centre for Ecology, Evolution and Conservation, School of Environmental SciencesUniversity of East AngliaNorwichUK

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