Crimson Snapper Lutjanus erythropterus

Northern Australian biological stock

The cross-jurisdictional northern Australian biological stock has components in the Northern Territory and Queensland. Each jurisdiction assesses that 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 both jurisdictions.

The Northern Territory manages the commercial harvest of Crimson Snapper and Saddletail Snapper together as red snapper. Crimson Snapper has made up around 22 per cent of the red snapper catch for the past 15 years. Saddletail Snapper comprises the majority of red snapper catch (averaged 78 per cent of the annual red snapper catch over the past 10 years), and is used as an indicator for the combined red snapper group. Analysis of Saddletail Snapper in 2013 using a stochastic stock reduction analysis model estimated egg production to be around 80 per cent of that before the start of the fishery, well above conventional fishery targets². Therefore, this part of the Crimson Snapper biological stock is not considered to be recruitment overfished.

The combined Northern Territory total allowable commercial catch for red snappers is 3800 tonnes (t). The commercial catch of Crimson Snapper in 2013 was 327 t. The 2013 assessment confirmed that the current harvest rate of red snappers is well below that required to achieve maximum sustainable yield. The low level of fishing mortality, compared with the total allowable catch, is unlikely to cause this part of the biological stock to become recruitment overfished.

For the Queensland part of the biological stock, the commercial catch in 2013 was 12 t. This contrasts with catches of 150–350 t per year during the period 2004 to 2011, and is the lowest catch since 2001. Since no information is available on biomass, there is insufficient information to confidently classify the status of this part of the biological stock.

Since the Northern Territory part of the biological stock constituted the majority of the total catch in 2013, the status of this part of the biological stock is indicative of the entire biological stock.

On the basis of the evidence provided above, the entire biological stock is classified as a sustainable stock.  

East coast Queensland biological stock

Crimson Snapper is taken in both the commercial and recreational sectors off eastern Queensland, probably in similar numbers by each sector.

Recreational harvest estimates group Saddletail and Crimson Snapper together because these two species are often not separately identified. The recreational harvest of these species was estimated to be approximately 65 000 fish in 2010³. The relative proportions of the two species in this catch are not known.

Since 2004, commercial harvest has dropped to around 20 t per year. At around the same time, there was an expansion of no-take marine reserves within the Great Barrier Reef Marine Park, and a quota management system for coral reef finfish species was introduced. Both factors are likely to have influenced commercial catch. Crimson Snapper is managed as part of the ‘other species’ quota category, which comprises many other coral reef finfish species. There is a cap on the total catch for the group, but no individual cap on any one species within the group. Although recreational fishing effort is not capped, the present level of combined fishing pressure is unlikely to cause the stock to become recruitment overfished.

Current biological information is unavailable, and no assessment has been completed for this stock. With no index of abundance, insufficient information is available to classify the status of this biological stock.

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

North West Shelf biological stock

Crimson Snapper is caught primarily on the north-west coast of Western Australia as a component of the multispecies Pilbara Fish Trawl Interim Managed Fishery, Pilbara Trap Managed Fishery, and Northern Demersal Scalefish Managed Fishery (in the Kimberley region of Western Australia)³. Crimson Snapper is assessed on the basis of the status of several indicator species caught in association with it (including Red Emperor—Lutjanus sebae, and Goldband Snapper—Pristipomoides multidens in the Kimberley region) that represent the inshore demersal suite of species occurring at depths of 30–250 m. The major performance measures used for these indicator species are estimates of spawning stock levels. The target level of spawning biomass is 40 per cent of the unfished level, and the limit level is 30 per cent of the unfished level. Data analysis using an integrated age-structured model determined that the spawning biomass levels of the indicator species were greater than 40 per cent of the unfished level in the Pilbara Fish Trawl Interim Managed Fishery, Pilbara Trap Managed Fishery and Northern Demersal Scalefish Managed Fishery in 2007⁴. The Crimson Snapper biological stock is therefore not considered to be recruitment overfished.

Fishing mortality (F)–based assessments⁵ indicated that the fishing levels on the indicator species were either lower than the target level, or between the target and threshold levels. These assessments use reference levels that are based on ratios of natural mortality (M) for each species, such that F_target = 2/3M, F_threshold = M and F_limit = 3/2M. This level of fishing mortality is unlikely to cause the biological stock to become recruitment overfished.

On the basis of the evidence provided above, the biological stock is classified as a sustainable stock.