BIOTIC Species Information for Modiolus modiolus
|Researched by||Lizzie Tyler||Data supplied by||University of Sheffield|
|Refereed by||This information is not refereed.|
|Reproductive Season||See additional information||Reproductive Location||Insufficient information|
|Reproductive frequency||Regeneration potential||No|
|Life span||51-100 years||Age at reproductive maturity||6-10 years|
|Generation time||6-10 years||Fecundity||1000000|
|Egg/propagule size||Fertilization type||Insufficient information|
|Reproduction Preferences Additional Information||Life span
Mussels over 25 years old are frequent in British populations, with occasional records of individuals of up to 35 years old. However, maximum ages are thought likely to be in excess of 50 years (Anwar et al., 1990).
The spawning season is variable or unclear and varies with depth and geographic location, probably related to temperature (de Schwienitz & Lutz, 1976; reviewed by Brown, 1984; Holt et al., 1998). For example:
Recruitment is sporadic and highly variable seasonally, annually or with location (geographic and depth) (Holt et al., 1998). For example:
Widdows (1991) noted that in Mytilus edulis larvae any environmental factor that increased the larval development time (e.g. temperature or food availability) increased larval mortality. This is probably true for other mytilid larvae, such as Modiolus modiolus.
Pre- and post-settlement mortality is high due to predation. Settling larvae prefer the byssus threads and aggregations or clumps of adults which provide a refuge from predators. In infaunal populations, however, the byssal threads and clumps of adults will be less accessible, and predation risk higher as a result (Holt et al., 1998). Most populations exhibit a bimodal size distribution of large, older specimens and small, younger specimens. Newly-settled horse mussels exhibit rapid growth prior to reaching maturity (see general biology), investing energy in growth rather than reproduction. Selection favours rapid growth to a size that is relatively immune to predation. Only the largest starfish and crabs can open mussels greater than 45-60mm and large horse mussels are thought to be largely predator free (Roberts, 1975; Seed & Brown, 1978; Holt et al., 1998). Comely (1978) noted that Modiolus modiolus <40mm were rarely found away from large horse mussels.
|Reproduction References||Holt et al., 1998, Brown & Seed, 1977, Comely, 1978, Schweinitz de & Lutz, 1976, Brown, 1984, Seed & Brown, 1978, Anwar et al., 1990, Seed, 1976, Jones et al., 2000, Seed & Brown, 1977, Jasim & Brand, 1989, Wiborg, 1946, Roberts, 1975, Seed & Brown, 1975, Jasim, 1986, Rowell, 1967, Julie Bremner, unpub data, Brown & Seed, 1977,|