Temporal and Spatial variability of the life history characteristics of Sand Flathead, Platcyphalus Bassensis

The structure of a fish population is determined by the balance between life history processes of reproduction, growth, and mortality (Sissenwine, 1984; Beverton & Holt, 1993) (Fig 1.1). Growth and reproduction as two major components of the life history traits are interconnected, energy channelled into the gonads detracts from growth (RoK 1984). There is thus a direct trade-off between growth and reproduction. The extent of such trade-off in driving population dynamics and the implication of fish condition, at the whole animal level, in quantifying variation in the differential allocation of energy yet to be addressed for fish. This study explore variability in the life history characteristics of sand flatliead, Platycephalus bassensis, in the context of energy tradeoffs between growth and reproduction. Understanding of energy tradeoffs develops our knowledge in identifying contributing factors responsible for variation of sub-populations.