Catch, Effort and CPUE

Total Striped Trumpeter catch in Tasmanian waters (south of latitude 39° 12’S) in 2020/21 was 8.2 t, including 6.2 t by Tasmanian vessels. Waters south of latitude 39° 12’S represent waters incorporated within the Offshore Constitutional Settlement Agreement (OCS) for Striped Trumpeter. The Commonwealth catch reported in 2020/21 was 1.9 t but catches are believed to have been substantially underreported in the past. Coupled with limited information on recreational catches, this situation represents a major source of uncertainty in estimating the total level of exploitation of Striped Trumpeter in Tasmanian waters.

Historically, Striped Trumpeter catch in Tasmanian waters included significant catches by Victorian vessels, peaking at around 37 t in the early 1990s. Since the mid-1990s, data from this sector have been unavailable, though it is assumed that subsequent catches have been reported in Commonwealth logbooks. Commonwealth catches have been consistently low compared to catches by Tasmanian vessels, with generally less than 5 t caught.

Total annual catch in Tasmanian waters was highest at over 110 t in the early 1990s, with Victorian vessels accounting for 17-39% of total catch. Total catch then fluctuated between 70-80 t through the mid-1990s before increasing again to over 100 t for two years in the late 1990s. Catches almost halved in 2000/01 to less than 50 t and have remained low since that time. A similar trend was observed across fishing gears used by Tasmanian vessels. In 2015/16, total catches of Striped Trumpeter fell to an historic low of 7.1 t (6.0 t from Tasmanian vessels). After slight increases in 2016/17 and 2017/18, total catch has remained around 7-8 t (6-7 t from Tasmanian vessels) for the most recent three fishing seasons (Figure above).

The recreational sector has targeted Striped Trumpeter as an important species. In 2000/01 and 2012/13, estimated recreational catch was less than the Commercial catch (Figure above) (Lyle 2005; Lyle et al. 2014b). However, estimates of recreational catch in 2011/12 and 2017/18 were substantially higher than the commercial catch (Figure above). Notably, recreational catch estimates do not fully represent catches by charter fishing boats.

Striped Trumpeter catches have historically been reported from all areas around the state, with the exception of the central north coast. In 2020/21, fishing activity was focused mainly on the southeast and west coasts for gear types.

Catch trends appear to reflect the influence of strong year classes assumed to have entered the fishery before 1998/99. This was followed by a lack of recruitment and associated declines in catches in the early 2000s. Industry representatives suggest that the trip limit of 250 kg from 2000 provided a disincentive for operators to target the species, which might have contributed to the continued reduction in dropline and handline effort since 2000/01 (Figure above). CPUE for handline and dropline, the currently dominant gear types on which Striped Trumpeter are caught, have been variable, with a general downward trend over recent years (Figure above).