Bottom Fishing Science

orange roughy Irish Sea Fisheries Board 2 rss


At the 10th Scientific Committee meeting held in Seoul, Korea (2022), several papers were presented from the Deepwater Working Group (DWG). The DWG, largely led by the delegations of New Zealand and Australia, has continued to develop vulnerable marine ecosystem (VME) indicator taxa guides for benthic bycatch in addition to distribution models for VME indicator taxa. Work is ongoing to further develop abundance models for VME taxa to complement the presence/absence models, with a focus on estimating catchability for different taxa. The SC recommended an exploration into the feasibility of developing and funding a research programme to achieve robust estimates of catchability of VME indicator taxa, to advance this research.

In addition, to VME research, stock assessment models for orange roughy stocks in SPRFMO have been further developed (SC10-DW01_rev1). Assessing the stock status and trends for orange roughy, given the life history characteristics, is challenging and estimates of biomass remain highly uncertain. The work presented in 2022 indicated that previous integrated assessment models are unreliable; however, such an approach could still be used to estimate the minimum biomass (Bmin) given plausible settings for stock productivity and vulnerability. Bmin was recommended for use as a proxy for B0 when calculating sustainable yield estimates for management purposes. The development of acoustic surveys to provide better information to the assessment model was one recommendation form WG, in addition to further evaluation of the ecosystem impacts of allowing for carrying forward unused portions of the annual TAC over multiple years. The latter was a provision proposed to improve the potential for viable fishery opportunities (and hence research data) within the constraints of the current spatial management regime. 

In addition to the scientific research, a dedicated intersessional Bottom Fishing Working Group was tasked with a comprehensive review of the bottom fishing CMM. This extensive body of work has been prepared for consideration at the 11th annual SPRFMO Commission meeting (COMM11-Doc07).


Background to Bottom Fishing in SPRFMO

Up until the early- to mid-2000s, most deep-sea fisheries in high seas areas of the south Pacific Ocean were regulated by domestic provisions imposed upon fishers by relevant flag states. The first push towards contemporary international fisheries management arrangements for non-highly migratory fisheries resources in the high seas areas of the South Pacific Ocean came in 2006, when Australia, Chile and New Zealand initiated a process of consultations to enable cooperation between states to address gaps that existed in the international conservation and management of fisheries resources and protection of biodiversity of the marine environment in the area.

Shortly after this, in 2006, the UNGA adopted Resolution 61/105 that called on States and Regional Fisheries Management Organisations (RFMOs) to take urgent action to protect VMEs from destructive fishing practices, including bottom fishing, in areas beyond national jurisdiction. Key elements of Resolution 61/105 included undertaking impact assessments to determine whether bottom fishing activities would have SAIs on VMEs, identifying VMEs, establishing move on protocols, sustainably managing the exploitation of deep-sea fish stocks, and establishing appropriate monitoring, control and surveillance mechanisms.

Consistent with UNGA Resolution 61/105, the Bottom Fishing Interim Measures adopted by participants at the third international consultation to establish the SPRFMO in 2007 required participants to “Not expand bottom fishing activities into new regions of the Area where such fishing is not currently occurring” which resulted in individual ‘footprints’ for Australia and New Zealand representing the spatial distribution of effort between 2002 and 2006.  The interim scientific working group subsequently recommended that areas that were ‘currently’ being fished be expressed as grid blocks of 20 minute resolution that had been fished over the period 2002 to 2006, this being the reference period subsequently chosen for limiting bottom fishing effort and catch to ‘existing levels’.

2009 was a significant year in the development of high seas bottom fishing management.  Following a series of international meetings, participants decided to establish a regional fisheries management organisation and on 14 November 2009, the 8th international meeting adopted the Convention on the Conservation and Management of High Seas Fishery Resources in the South Pacific Ocean. Also in 2009, the FAO published the International Guidelines for the Management of Deep-Sea Fisheries in the High Seas (FAO 2009), which provided recommendations on governance frameworks and management of deep-sea fisheries with the aim to ensure long-term conservation and sustainable use of marine living resources in the deep sea and to prevent SAIs on VMEs. Importantly, these guidelines also defined SAIs and VMEs, with these definitions having been used widely by demersal RFMO/As to the current day.  In the same year, the UNGA adopted Resolution 66/68 reinforcing earlier Resolutions, and calling on States and RFMO to apply a precautionary approach and these FAO Guidelines.

Based on the early international agreements, UNGA Resolution 61/105 and the  (FAO 2009) guidelines, once SPRFMO entered into force in 2012, Australia and New Zealand set about implementing management arrangements that would satisfy the varied international obligations and objectives as manifested through the SPRFMO Convention and related non-binding instruments.

The first formal CMM for the Management of Bottom Fishing in the SPRFMO Convention Area came into force on 4 May 2014. The CMM was reviewed annually, with minor changes, while Australia and New Zealand progressed a more comprehensive review.

In 2016, the UNGA adopted Resolution 71/123 which strongly emphasised the importance of strengthening procedures for carrying out, reviewing and evaluating impact assessments, taking into account individual collective and cumulative impacts, and ensuring that any measures are based on best available scientific information, and adopt an ecosystem approach.  It also noted the unevenness of implementation of the earlier resolutions. 

Following a recognition by the SPRFMO Commission that the different implementation of SPRFMO bottom fishing measures by members was sub-optimal, Australia and New Zealand initiated discussions to agree and implement a revised bottom fishing measure so that consistent management arrangements would apply to all SPRFMO Members engaged in established bottom fisheries in the SPRFMO Convention Area. There were also ongoing concerns expressed by the international community, in particular environmental non-government organisations, that the measures in existence (and how they were being interpreted) were not meeting the intended objectives of the relevant UNGA Resolutions and associated instruments (e.g., the FAO 2009 Deep-Sea Guidelines).

In response, CMM03-2019 provided a comprehensive set of rules based on a spatial management approach that aimed to ensure the long-term conservation and sustainable use of deep-sea fishery resources. The approach aimed, through the protection of a large proportion of the predicted distribution of VME indicator taxa, to provide assurance that bottom fishing within the Evaluated Area would not have SAIs on VMEs. The measure also contained complementary measures, including VME encounter thresholds, move-on protocols and review processes within areas that are open to fishing to provide further assurance that SAIs on VMEs will be prevented. The SPRFMO Scientific Committee reviewed and agreed that the methodology underpinning the measure was appropriate. The measure included:

a)       An Evaluated Area within which the distribution of VME indicator taxa has been mapped between depths of 200 m and 3000 m using predictive models and which considers cumulative impacts of fishing, an improvement on the existing approach (which considers impacts only by individual flag State);

b)      Three Management Areas within the Evaluated Area in which bottom fishing may be conducted, based on spatial prioritisation using Zonation software which are implemented consistently across the membership and differentiated by gear (bottom trawl, midwater trawl and bottom longline);

c)       A VME encounter protocol within the bottom and midwater trawl Management Areas, to be implemented consistently across the membership;

d)      Measures to assess, monitor and control bottom fisheries.