Scalefish Southern Calamari Biology

Biology

SpeciesSepioteuthis australis
Common NameSouthern calamari
ImportanceKey
HabitatShallow to inshore water (Gomon et al., 2008)
DistributionEndemic to southern Australia and northern New Zealand (Gomon et al., 2008)
DietVarious crustaceans and fishes (Norman, 2000)
Stock StructurePreliminary genetic studies revealed a minimum of 5 distinct stocks in Australia, with 98% of the Tasmanian population belonging to a single genetic stock that is also found in South Australia, New South Wales and Western Australia, suggesting some degree of connectivity. A more comprehensive genetic study revealed a single stock across southern Australia and that Tasmanian is particularly important in terms of reproduction (Triantafillos and Adams, 2001; Smith et al. 2015b)
MovementHighly mobile, including migrations between feeding and spawning grounds
M (Natural Mortality)High; embryo mortality rate between 5 – 25% (Steer et al., 2004)
Maximum Age (years)< 1 (275 days for males, 263 days for females) (Pecl et al., 2004; Pecl and Moltschaniwsky, 2006)
Growth Rate (non-von Bertalanffy)Rapid: 7 – 8% body weight per day (<100 days old), 4 – 5% body weight per day (>200 days old); growth for males and females after recruitment (age t >80 days) L=2e^(-6) t^3.5332, where L = dorsal mantle length (mm); variability in growth explained partly by temperature and food availability (warmer seasons means faster growth), but also likely a genetic component.
Length (L; dorsal mantle length (mm))– Weight (W; g) RelationshipW=0.00081L^2.427 (Pecl et al., 2004; Triantafillos, 2004; Pecl, 2004)
Size at Maturity (mantle length; cm)18.45 (females) Pecl and Moltschaniwsky, 2006)
Spawning SeasonSeptember – February with low levels likely year-round
Spawning LocationGreat Oyster Bay (known ground)
Additional Spawning InformationMultiple spawners reproductively active over several months (up to 3.5 months); females deposit eggs in collective egg masses, attaching capsules to substrate by small stalks (Pecl and Moltschaniwsky, 2006; Pecl et al., 2004; Moltschaniwskyj and Pecl, 2003)
Early Life HistoryIncubation time 4 – 8 weeks, depending on water temperature; hatchlings (2.4 – 7mm) swim to surface and can be found near spawning grounds for 20 – 30 days; habitat and ecology at age 20 – 80 days unknown; from 80 – 150 days old juveniles found in deeper water adjacent to spawning ground; individuals available to the fishery 90 – 120 days old (Steer et al., 2002; Pecl, 2000; Pecl, 2004)