Yellowtail Kingfish Seriola lalandi

Eastern Australian biological stock 

The cross-jurisdictional eastern Australian biological stock occurs throughout Commonwealth waters, New South Wales and Queensland. Each jurisdiction assesses the part of the biological stock that occurs in its waters. The status presented here for the entire biological stock has been established using evidence from the three jurisdictions.

Reported catch from the Queensland fishery is relatively minor, ranging from 3 to 11 tonnes (t) per year over the period 2004 to 2013. Recreational charter catch was estimated to be around 1 t, but limited information is available regarding the broader noncharter recreational catch.

Commonwealth fisheries comprise a relatively small catch of Yellowtail Kingfish across a number of fisheries. For the period 2000 to 2013, catch fluctuated between about 5 t and 64 t, averaging around 25 t per year. More than 80 per cent (23.6 t) of the catch in 2013 was taken using hook and line (dropline, autoline and bottom line) on the northern West Norfolk Rise, mainly when targetting Blue Eye Trevalla (Hyperoglyphe antarctica). A further 4.2 t (15 per cent of the catch in 2013) was caught as bycatch in the Commonwealth Trawl Sector, and less than 1 t was caught in the Commonwealth south-east Gillnet, Hook and Trap Sector. There are no specific management arrangements for Yellowtail Kingfish in Commonwealth fisheries. No data other than catch and effort are collected, and no Commonwealth assessment has been conducted for this stock.

Information on the eastern Australian stock is therefore primarily based on catch information from New South Wales. Catch rates and size compositions of commercial landings from the New South Wales component of the biological stock are assessed annually. Yellowtail Kingfish are currently assessed as being growth overfished in New South Wales waters, despite an increase in minimum legal length from 60 to 65 cm in 2007. However, New South Wales commercial landings in 2013 (around 83 t) are now substantially lower than the average during the late 1980s (more than 500 t per year). As well, commercial median catch rates (kilograms per day of line fishing) have increased from around 3 kg per day in the mid-1990s to an average of more than 22 kg per day since 2009. Although the fishery continues to be based largely on juveniles, the size composition in commercial landings has remained relatively stable since the 1990s, except for the effect of increasing the minimum legal length in 2007. The above evidence indicates that this stock is unlikely to be recruitment overfished.

However, there have been no age composition estimates since 2001⁶. This analysis, which used age data from 1998 to 2000, indicated that fishing mortality was likely to be greater than natural mortality, and the spawning potential ratio was likely to be below the 20 per cent limit reference point ⁶. These estimates, which are based on data that are around 15 years old⁷, are outdated, but length composition data suggest that there have been no major changes to the fishery during the last 15 years. The limited information on the quantities or sizes of Yellowtail Kingfish harvested by the recreational fishery in New South Wales since 2000 results in considerable uncertainty around estimates of total fishing mortality. As a result of the conflicting evidence above, and the substantial uncertainty around total mortality levels, there is insufficient information available to confidently classify the status of this stock.

On the basis of the evidence provided above, the entire biological stock is classified as an undefined stock.  

Western Australian biological stock 

Yellowtail Kingfish are not commonly encountered in Western Australia. As a result, there is no commercial targeting of Yellowtail Kingfish and limited recreational effort focused on this species in Western Australia. Commercial catches of Yellowtail Kingfish have always been low (less than 1 t), and an estimated 11 t was reported from the state in 2013 (1 t commercial; 10 t recreational). As a result, insufficient information is available to classify the status of this stock.

On the basis of the evidence provided above, the biological stock is classified as an undefined stock.