This is something we should all know about as Tuross Lake is now officially recognised as Flathead Trophy fish “Hot Spot”. It also has implications in regards to the tagging of fish procedures that fishing club members are about to implement.
Some notes about Flathead and this graph
An age graph from Julian Hughes at the DPI research department. It provides data on the age of a flathead at a certain length. You may find it interesting to get an idea of how old the “trophy sized” flatties you are catching and for our tagging program are.
It also provides more evidence to support the theory that just about all big Flathead are females. Also that these big females are relatively old.
Julian advises that the graph is split into 5 cm length classes with the median (most common) age for each size class. The shaded area is the spread of ages for each size class. So for a flatty of between 50 and 54 cm length, it is most likely to be 4 years old, but with a usual spread (90%) of a minimum of 1 or a maximum of 7 years old.
The variation is mainly due to the different growth of the sexes as females grow much faster than males after 2 years of age. Females also reach much larger sizes than males with the maximum size for females around 100 cm, but for males is just 60 cm. The oldest female flatty so far recorded in NSW was 16 years old (and 88.5 cm), the largest was 98.5 cm (and 13 years old). Whereas the oldest and largest male was just 11 years old and only 61.5 cm.
The data has come from over 5000 duskies collected from NSW waters between 1994 and 2011 from the Clarence south to Wallaga Lake.
