A fishery for toothfish (Dissostichus mawsoni and Dissostichus eleginoides) operates in Division 58.4.2 in the Western Indian Ocean, and the fishing grounds are divided into five small-scale research units (Figure 1). This region is subject to sea-ice which extends north throughout the area during winter, and retreats during summer.

Figure 1 Location of the fishery for Dissostichus spp. in Division 58.4.2 and small-scale research units A-E.

Set longlines
The main species caught is D. mawsoni which is taken using longlines only. Longline fishing is permitted year-round and vessels use deepwater, bottom-set longlines which must comply with CCAMLR’s mitigation measures aimed to reduce the incidental mortality of seabirds during longline fishing. Vessels deploy either autolines, some using integrated-weighted lines, or Spanish-type longlines.

For the 2008/09 fishing season, CCAMLR set a precautionary catch limit for Dissostichus spp. of 70 tonnes in Division 58.4.2. This catch limit was subdivided among the small-scale research units A (30 tonnes) and E (40 tonnes). Small-scale research units B, C and D were closed to fishing.

The catch history of the fishery for Dissostichus spp. in Division 58.4.2 is summarised in Table 1. The estimated catch of toothfish taken by illegal, unreported and unregulated (IUU) fishing in Division 58.4.2 ranges up to 197 tonnes per season.


Table 1 Catch and effort in the fishery for Dissostichus spp. in Division 58.4.2 by CCAMLR seasons (i.e. 2004/05 is 1 December 2004 to 30 November 2005).

Season	Regulated fishery						Estimated IUU catch (tonnes)	Total removals (tonnes)
	Effort (number of vessels)		Dissostichus spp
			Catch limit (tonnes)	Reported catch (tonnes)
	Limit	Reported		D. eleginoides	D. mawsoni	Total
2002/03	1	1	500	0	117	117	98	215
2003/04	-	1	500	0	20	20	197	217
2004/05	8	4	780	1	125	126	86	212
2005/06	7	3	780	<1	163	164	192	356
2006/07	8	3	780	0	124	124	197	321
2007/08	14	3	780	<1	216	217	0	217

Precautionary catch limits apply to species taken as by-catch in the fishery. Limits are set for macrourids (grenadiers) and rajids (skates and rays) in proportion to the catch limit for Dissostichus spp., and these limits are subdivided among the small-scale research units. Vessels are generally required to release rajids alive from the lines by cutting snoods and, when practical, removing hooks. Precautionary catch limits are also set for all other finfish by-catch species. Catches of macrourids, rajids and other finfish by-catch species reported from the fishery are summarised in Table 2.


Table 2 Catch history for by-catch species (macrourids, rajids and other species), catch limits and number of rajids released alive in Division 58.4.2 by CCAMLR seasons.

Season	Macrourids		Rajids			Other species
	Catch limit (tonnes)	Reported catch (tonnes)	Catch limit (tonnes)	Reported catch (tonnes)	Number released	Catch limit (tonnes)	Reported catch (tonnes)
2002/03	250	12	250	0	-	100	1
2003/04	80	1	50	0	-	100	0
2004/05	124	28	50	3	3	60	2
2005/06	124	4	50	0	-	60	1
2006/07	124	7	50	0	-	60	0
2007/08	124	12	50	0	-	60	1

The level of risk of incidental mortality of seabirds in Division 58.4.2 has been assessed as average to low (Category 2). Estimated incidental catch rates and catches of seabirds from the fishery is zero (Table 3). However, incidental catches of seabirds during periods of IUU fishing (Table 1) are likely to be higher than those reported by licensed vessels because IUU vessels do not apply mitigation measures.

Marine mammal interactions or mortalities in the fishery have not been observed.


Table 3 Seabird by-catch limit, observed mortality rate and total estimated mortality of seabird by-catch in Division 58.4.2 by CCAMLR seasons.

Season	By-catch limit (number of birds)	Mortality rate (birds/thousand hooks)	Total estimated mortality (number of birds)
2002/03	3*	-	-
2003/04	3*	-	-
2004/05	3*	0	0
2005/06	3*	0	0
2006/07	3*	0	0
2007/08	3*	0	0
* Per vessel during daytime setting

The fishery is in an exploratory phase and is subject to a notification procedure within CCAMLR’s regulatory framework for managing fisheries (see CCAMLR Conservation Measure 21-02).

The operation of fishing gear is strictly regulated and vessels must comply with CCAMLR’s mitigation measures which minimise the attraction of seabirds to fishing vessels and reduce the risk of birds seizing baited hooks, particularly during the period when the lines are set (see Conservation Measure 25-02).

Fishing vessels must also report potential encounters with vulnerable marine ecosystems (VMEs). Vessels which exceed a threshold of VME-indicator organisms per longline line segment (5 or more VME-indicator units) must notify the encounter to the CCAMLR Secretariat (see Conservation Measure 22-07, see also http://www.ccamlr.org/pu/E/sc/fish/forms.htm). Risk areas are declared where 10 or more VME-indicator units are recovered from a single line segment, and these areas shall remain closed to bottom fishing until they have been reviewed by CCAMLR’s Scientific Committee and management actions are determined by the Commission. In addition, fishing is prohibited in depths shallower than 550 m in order to protect benthic communities.

Vessels operating in this fishery are also subject to a by-catch move-on rule: If the by-catch of any one species is equal to or greater than 1 tonne in any one haul or set, then the fishing vessel is required to move to another location at least 5 nautical miles distant, and the vessel can not return to any point within 5 nautical miles of the location where the by-catch exceeded 1 tonne for a period of at least five days. Vessels catching macrourids may also be required to cease fishing in a small-scale research unit if the catch of macrourids reaches a specified threshold within a given time period.

Each vessel participating in the fishery is required to carry at least two scientific observers, one of whom is appointed in accordance with the CCAMLR Scheme of International Scientific Observation, on board during all fishing activities.

Vessels must also conduct fishery-based research to collect detailed biological data on the target and by-catch species, and to tag and release Dissostichus spp. a specified rate per tonne green weight caught.

Flag States must report catches and fishing effort in accordance with CCAMLR’s real-time Catch and Effort Reporting System, and detailed catch and effort data on a haul-by-haul basis. Vessels are tracked using CCAMLR’s centralised Vessel Monitoring System, and all transhipments, landings and trade of Dissostichus spp. are logged using CCAMLR’s Catch Documentation Scheme.

Most toothfish fisheries have also been targeted at various times by IUU fishing activities. IUU fishing undermines CCAMLR’s management objectives by threatening the sustainability of toothfish stocks and seabird populations which are prone to IUU activities. In response, CCAMLR has developed a set of integrated measures to combat IUU fishing. These measures include a Catch Documentation Scheme to monitor landings and the global trade of toothfish, strict vessel licensing requirements, at-sea and port vessel inspections, a comprehensive list of IUU vessels and the development of a centralised Vessel Monitoring System (see Conservation Measures 10-01 to 10-09).

CCAMLR reviews the management advice for each fishery annually, and updates the schedule of Conservation Measures in force which regulates fisheries in the CCAMLR Convention Area. The fishery for toothfish in Division 58.4.2 is managed under Conservation Measure 41-05 and associated measures.