Mackerel Icefish (2018)
Mackerel Icefish is a sustainable species. It occurs around Heard Island and the McDonald Islands in the Southern Ocean Antarctic ecosystem.
Stock Status Overview
|Commonwealth||Heard Island and McDonald Islands||HIMIF||Sustainable||Spawning stock biomass|
- Heard Island and McDonald Island Fishery (CTH)
Genetic studies have concluded that Mackerel Icefish at Heard Island and the McDonald Islands constitute a single biological stock, which shows differences from icefish populations in the Atlantic and on the neighbouring Kerguelen Plateau [Williams et al. 1994, Williams et al. 2001].
Here, assessment of stock status is presented at the biological stock level—Heard Island and McDonald Islands.
Heard Island and McDonald Islands
The Heard Island and McDonald Islands Fishery (Commonwealth) (HIMIF) falls within the Convention Area of the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). This intergovernmental organisation was established to conserve and manage the Southern Ocean Antarctic ecosystem. CCAMLR employs precautionary harvest strategies that consider the role of target species within the larger ecosystem. For Mackerel Icefish, the CCAMLR harvest strategy, which includes decision rules to set the catch limit, requires that the spawning stock biomass must be maintained at 75 per cent of the level that would occur in the absence of fishing at the end of a two-year model projection.
The Mackerel Icefish assessment in 2017 for the HIMIF used an abundance index from a random stratified trawl survey [Nowara et al. 2017]. Given the high interannual variability in the population abundance of this species, CCAMLR does not use an estimate of unfished biomass; the total allowable catch (TAC) is set to allow a harvest of only 25 per cent of the current biomass over a two-year period. The most recent assessment estimates the 2017 biomass of Mackerel Icefish to be 3 901 tonnes (t) [Maschette et al. 2017]. Using the CCAMLR harvest strategy decision rules, the recommended TAC for the 2017–18 fishing season was calculated to be 526 t, which it is estimated will ensure maintenance of a spawning stock biomass of at least 75 per cent of unfished biomass over the two-year projection period [Maschette et al. 2017]. The stock is not considered to be recruitment impaired. This TAC was endorsed by CCAMLR after review [CCAMLR 2017a, CCAMLR 2017b]. This level of fishing mortality is unlikely to cause the stock to become recruitment impaired [Patterson et al. 2018].
On the basis of the evidence provided above, the Heard Island and McDonald Islands biological stock is classified as a sustainable stock.
Mackerel Icefish biology [Williams et al. 2001]
|Species||Longevity / Maximum Size||Maturity (50 per cent)|
|Mackerel Icefish||≥ 4 years, ~450 mm TL||2 years; 240–260 mm TL|
|Individual transferable quota|
|Commercial||557.00t in HIMIF|
- Heard Island and McDonald Island Fishery (CTH)
Commonwealth – Recreational (a) The Australian Government does not manage recreational fishing in Commonwealth waters. Recreational fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters, under its management regulations; and (b) There is no recreational or Indigenous fishing for Mackerel Icefish.
Commonwealth – Indigenous The Australian Government does not manage non-commercial Indigenous fishing in Commonwealth waters, with the exception of the Torres Strait. In general, non-commercial Indigenous fishing in Commonwealth waters is managed by the state or territory immediately adjacent to those waters.
- Commission for the Conservation of Antarctic Marine Living Resources 2017a, Report of the Working Group on Fish Stock Assessment, WG-FSA-17, CCAMLR Working Group on Fish Stock Assessment, Hobart, 2–13 October 2017.
- Commission for the Conservation of Antarctic Marine Living Resources 2017b, Report of the thirty-sixth meeting of the Scientific Committee, SC-CAMLR-XXXVI, CCAMLR Scientific Committee, Hobart, 16–20 October 2017.
- Maschette, D, Burch, P, Yates, P and Welsford, DC 2017, A preliminary assessment and revised growth model of mackerel icefish (Champsocephalus gunnari) in Division 58.5.2, based on results from the 2017 random stratified trawl survey, WG- FSA-17/22, CCAMLR Working Group on Fish Stock Assessment, Hobart, 2–13 October 2017.
- Nowara, GB, Lamb, TD and Ziegler, P 2017, The random stratified trawl survey to estimate the abundance Dissostichus eleginoides and Champsocephalus gunnari in waters surrounding Heard Island (Division 58.5.2) for 2017, WG-FSA-17/14 Rev 1, CCAMLR Working Group on Fish Stock Assessment, Hobart, 2–13 October 2017.
- Patterson, H and Mazur, K 2018, Heard Island and McDonald Islands Fishery, in H Patterson, J Larcombe, S Nicol and R Curtotti (eds), Fishery status reports 2018, Australian Bureau of Agricultural and Resource Economics and Sciences, Canberra, 422-432.
- Williams, R, Smolenski, AJ and White, RWG 1994, Mitochondrial DNA variation of Champsocephalus gunnari Lonnberg (Pisces: Channichthyidae) stocks on the Kerguelen Plateau, southern Indian Ocean, Antarctic Science, 6: 347–352.
- Williams, R, van Wijk, E, Constable, A and Lamb, T 2001, The fishery for Champsocephalus gunnari and its biology at Heard Island (Division 58.5.2), WAMI-01/04, CCAMLR Workshop on Assessment Methods for Icefish, Hobart.