Esteves and Andrade, 2008


Esteves, E. and Andrade, J.P. (2008) Diel and seasonal distribution patterns of eggs, embryos and larvae of Twaite shad Alosa fallax fallax (Lacépède, 1803) in a lowland tidal river. Acta Oecologica, pp. 172-185

Associated characteristics

Species Development state Trait Primary Data Secondary Data
Alosa alosa Larvae Reaction to light Positive phototropism Photopositive
Alosa fallax Egg Egg size after water-hardening Relatively large (1.7-4.5 mm) with a wide perivitelline space 3.1 mm
Alosa fallax Egg Egg adhesiveness Non-adhesive Non-Adhesive
Alosa fallax Larvae Initial larval size Individuals of A. f. fallax with depleted yolk-sacs but still with some evidence of a fin fold were catagorised as shad larvae (herein embryos were 4.92-10.79 mm SL while larvae were 5.65-20.40 mm SL) 7.85 mm
Alosa fallax Spawning conditions Spawning migration period The upstream migration and spawning of European Alosa spp seems to be triggered by water temperature (above 10-12°C) and predominantly influenced by estuarine tides and river flows/discharge No data
Alosa fallax Spawning conditions Spawning season Twaite shad eggs, embryos and larvae occurred from late-March to mid-June, with particularly higher densities during a 5-week period from late-April through to the last week of May. ['March', 'April', 'May', 'June']
Alosa fallax Spawning conditions Spawning water type In this study, eggs, embryos and larvae of Twaite shad were only found in the upstream, riverine stations located close to the upper boundary of estuarine influence and the vicinity of the suspected spawning grounds in the River Mira No category