Southern Sand Flathead Biology


SpeciesPlatycephalus bassensis
Common NameSouthern Sand Flathead
HabitatSheltered sand and silt habitat
Depth≤ 100 m (Edgar, 2008; Tilzey et al., 1990)
DistributionWestern Australia to New South Wales, around Tasmania (Edgar, 2008; Gomon et al., 2008)
DietFish and crustaceans (Ayling et al., 1975)
Stock StructureNo information available
MovementSeasonal movements between inshore and offshore in eastern and southeast Tasmanian waters. Information from tagging, larval sampling and growth rate studies indicate distinct biological stocks in Port Phillip Bay, Bass Strait, and south eastern Tasmania (Kailola et al. 1993; Jorden at al., 1998)
M (Natural Mortality)0.16 – 0.25 (per year in south eastern Tasmania), possibly 0.28 – 0.59 per year elsewhere (Ewing et al., 2014; Bani, 2005)
Maximum Age (years)20 (Bani, 2005)
Maximum Length (total length; cm)51.5 (Edgar, 2008; Gomon et al., 2008)
Maximum Weight (g)3100 (Edgar, 2008; Gomon et al., 2008)
Female K (von Bertalanffy growth parameter)0.51 (Bani, 2005; Gomon et al., 2008; Ewing et al., 2014)
Male K (von Bertalanffy growth parameter)0.6
Female t0 (age (years) when length = 0)0
Male t0 (age (years) when length = 0)0
Female L∞ (asymptotic von Bertalanffy length (total length; cm))36 (total length)
Male L∞ (asymptotic von Bertalanffy length (total length; cm))30 (total length)
Size at Maturity (length (total length; cm) at which 50% of population are sexually mature)24.7-26.3 (females), 21.7 (males)
Age at Maturity (age (years) at which 50% of population are sexually mature)2.6-5.2 (females), 2.5-3.5 (males) (Bani and Moltschaniwsky, 2008)
Spawning SeasonOctober – March (peak October – December)
Spawning LocationThroughout range in southern and eastern Tasmania, including on the continental shelf (Jordan, 2001b; Kailola et al., 1993)
RecruitmentNo-stock recruitment relationship established
Early Life HistorySettlement occurs over extended period, 4 – 14 months after spawning; size at settlement approximately 2.1 cm (Jordan, 2001b)
Gillnet Post Release SurvivalModerate: 50% (all soak durations including both graball and mullet nets) (Lyle et al., 2014)
Rod and Line Post Release SurvivalHigh: >99% for circle hooks and 94-97% for conventional hooks (Lyle et al., 2007)