Lundvall, S.

The commercial fishery of Saba Bank, Netherlands Antilles, was assessed for six months from June 1 through November 30, 2007, by conducting port sampling interviews with Saban commercial fishermen to obtain information on fishing effort, gear usage, landings and species composition of catches. Results from our survey are compared to previous studies to provide an updated assessment of the Saba Bank commercial fishery.
 
The fishery can be summarized as follows. A small fishing fleet of approximately ten vessels operates from Fort Bay, Saba Island, and conducts small-scale commercial fishing on Saba Bank. Saban commercial fishermen may participate in either or both of two distinct types of fisheries: a lobster trap fishery and a “redfish” trap fishery. The two trap fisheries account for almost all commercial landings while other fishing methods (e.g. hook & line) make only a minor contribution to total landings from Saba Bank. Specific patterns of effort, landings and catch composition are identified within each trap fishery.
 
Lobster trap fishing is the more prevalent and economically significant Saba Bank fishery. Lobster catch rate is 0.84 lobster per trap-haul and 184 pounds per trip. Catch rates vary significantly with season. Projected annual lobster landings are 184,000 lbs (83.6 mt) with an exvessel value of US $1.3 million per year. The lobster trap fishery also harvests a diversity of “mixed fish” (shallow water reef fishes). Average catch rate of mixed fish is 0.5 pounds per traphaul and 37.8 pounds per trip, with projected annual mixed fish landings of 37,700 pounds (17.1 mt) at an ex-vessel value of US $68,700 per year.
 
The fish trap fishery targets “redfish” - an assortment of deepwater snapper species that is dominated by silk snapper, blackfin snapper, and vermilion snapper. These three lutjanid species comprise > 91 % of fish trap catch. Average catch rate of redfish in fish traps is 10 pounds per trap-haul, and 291 pounds per trip. Projected annual fish trap landings of redfish are 90,800 pounds (41.3 mt) with an ex-vessel value of US $289,000 per year. Fish trap landings also include a small quantity of mixed fish (< 9 % by weight of finfish in fish trap landings) comprised of a diversity of species but dominated by red hind and lane snapper. Catch rate of mixed fish in fish traps is 1 pound per trap haul and 27 pounds per trip.
 
Viewed as a whole, 2007 landings from Saba Bank by Saban commercial fishermen are projected to exceed 145 metric tons in 2007 with an ex-vessel value greater than US $1.6 million. Comparison to previous fisheries studies indicates that the Saba Bank commercial fishery is relatively stable in terms of total fishing effort, total landings, economic value, and fishing methods. The following trends were identified. Compared to 1999-2000, lobster catch rate in 2007 was approximately 33 % lower in terms of weight per trap-day, but there was only a small (6.3 %) reduction in total landings of lobster. A shift to smaller lobster size was not indicated by length frequencies: average carapace length was larger in 2007 (11.2 cm) than in 1999-2000 (10.7 cm). However, lobster fishing effort as measured by trap haul rate was 31 % greater in 2007 (80.9 trap-hauls per trip) than in 1999-2000 (62.0 trap-hauls per trip). We estimate that the total number of lobster traps in use on Saba Bank increased from 1,426 traps in 1999-2000 to 1,862 traps in 2007. Collectively, these findings indicate that Saba Bank fishermen of 2007 exert a greater fishing effort in order to maintain lobster landings at year 2000 levels. An increase in fishing effort coupled with a decrease in observed catch rate could suggest that lobster harvests are now at or exceed the maximum sustainable yield for Saba Bank stocks. However, more definitive conclusions about trends in lobster stock abundance are not possible owing to the limited time frame of available fisheries data sets.
 
The importance of redfish, as a percentage of total annual landings, has increased by three-fold since 2000. Yet, the Saba Bank redfish fishery is characterized by a lack of information. Stock densities are either unknown, or may be based on very optimistic calculations. The commercial fishery now harvests redfish primarily with fish traps, in contrast to hook & line fishing methods that predominated in 2000. Given that stock size remains poorly known, the current practice of harvesting almost exclusively juvenile fishes is a risky fisheries strategy. If reproductive output by silk snapper stocks is sufficiently reduced by harvesting it may lead to abrupt population declines or even a stock crash.
 
We recommend that the following actions should be priorities for management of Saba Bank fisheries resources: establishment of a program for long-term commercial fisheries monitoring, elimination of anchoring by large vessels on Saba Bank, development of a framework for monitoring and regulating the harvest of deepwater snappers, implementation of conservation measures to protect a red hind spawning aggregation, and initiation of a study to evaluate ghost fishing by lost traps.

A small submersible remotely operated vehicle (ROV) was used to explore mid-depth habitats of Saba Bank – a submerged carbonate platform in the northeastern Caribbean Sea. The ROV enabled observation and specimen collection to greater depths (40 to > 150 m) than possible with conventional scuba methods. The topography, substrate, benthic communities and fish assemblages of a prominent front reef system at Overall Bank were examined in some detail. Observations made from ROV indicate that substrate and benthic communities show consistent zonation patterns along the depth gradient of the front reef slope. A transition in the reef fish assemblage was also evident, though less pronounced, along this same depth gradient. Fish diversity (number of species observed per survey) was greatest in the reef crest zone and declined with depth, however sightings of commercially important lutjanids species such as silk and blackfin snapper increased with depth. Significant cover by reef-building corals (i.e. constructional reef development) was only evident in the reef crest zone, and terminated at 38 to 42 m depth. Substrate of the transition slope zone, from 42 m to 75 m depth, was primarily a hard bottom consisting of consolidated reef structures and rubble with sand interspersed. Sponges, gorgonians and macro algae dominated the benthic community there. In the deep slope zone (> 75 m depth), a soft bottom substrate predominated that was composed of fine, readily resuspended sediments together with scattered rubble fragments. Benthic invertebrates were very sparse in the deep slope zone. In addition to the surveys at Overall Bank, four ROV surveys were made at two other Saba Bank areas: Poison Bank and Grapplers Bank. The substrate at Poison Bank was comprised of coralline algal nodules or “rhodoliths” which formed extensive rhodoliths beds. At Grapplers Bank, a steep rocky escarpment was explored. The near-vertical rocky scarp began at 120 m depth and extended down slope beyond the limits of the ROV survey (157 m depth). Observations made from ROV at Overall Bank suggested a continuous reef system that is relatively uniform and predictable at mid-depths in terms of its structure, substrate composition, and community zonation patterns. In contrast, the few observations made by ROV at Poison Bank and Grapplers Bank revealed habitats that were quite different from those at Overall Bank. This implies that future ROV explorations to new areas of Saba Bank are likely to reveal still greater diversity in mid-depth habitat types.

Findings

A management plan was prepared in close consultation with a considerable number of stakeholders and stakeholder group representatives.

The plan specifies management goals and strategies for the Saba Bank Management Organization (SBMO) related to the organization mission. It also identifies the major existing and potential threats and issues facing the Bank from ecological, social and cultural perspectives and includes substantial input from stakeholders. It is designed to be an adaptive management tool.

Below is a very brief overview of the management plan

Part I: Saba Bank Background Information

• Location and situation
• Geology and geomorphology
• Marine habitats, flora and fauna and natural resources
• Human uses
• Critical threats to the Saba Bank:
• Overexploitation of fishery resources
• Impacts from tanker anchorage on benthic communities
• Impacts of tanker traffic on fishermen and traps
• Global climate change

PART II: Management Environment

• Vision: To secure a natural protected area that represents a unique and spectacular ecosystem; Mission: To contribute to the preservation of Saba’s natural heritage and promote the sustainable use of the natural resources; and Goals.
• Governance
• Human resources
• Physical resources
• Finance
• Stakeholders

Summary of Issues (see below)

Management Recommendations (PART III: Management Environment)

Key issue: Create a clearly defined conch reserve on the Saba Bank.
Actions: Create and implement the queen conch reserve with no commercial take of conch. Research into queen conch stocks.

Key issue: Monitor the landings of commercial fish catches (there is currently very little data available on the yearly landings from the commercial fishermen of Saba).
Actions: Collect records of fishing activity on the Saba Bank. Develop a system to report landing from commercial fishermen. This dataset will lay the foundation for establishing a long-term commercial fisherman reporting system, which in turn will enable the SBMO to assess the state of the Saba Bank’s fish stocks.

Key issue: Enforcement of fisheries regulations (there is currently minimal enforcement of the fisheries regulations)
Actions: Collaboration; work with the Government, Harbour Office and Police to establish clear enforcement procedures and publicize the outcome. Encourage local fishermen to work with the police in the enforcement of the regulations. The SCF is in the process of having one of their rangers trained as a special agent.

Key issue: Monitor red hind spawning aggregation; assist in the development of a spawning aggregation closed season.
Actions: Gather initial information: determine where the majority of the fishermen are from and gauge trends in fish densities during the aggregations. Consult with stakeholders, including both the public and fishermen. Provide assistance in draft legislation for closing the spawning aggregation.

Key issue: Monitor tanker anchorage damage on the Saba Bank.
Actions: Monitor the impacts of anchoring. Prevent anchorage within the 12 miles of territorial waters. Provide whatever support is required for the Central Governments proposal to have the Bank recognized as a Particularly Sensitive Sea Area (PSSA).

Key issue: Evaluate the potential for artificial reef development on the Saba Bank.
Actions: Create and monitor an experimental artificial reef.

Key issue: Monitor and evaluate coral health.
Actions: Continue to monitor bleaching. Continue to monitor the state of the coral at existing sites established in 2007 on a regular basis. Adapt methods where appropriate. Co-ordinate with other islands. Communicate methods and results with St. Eustatius, St Maarten, and other DCNA islands, as well as the regional Global Coral Reef Monitoring Networkm (GCRMN) nodes.

Key issue: Facilitate and promote research from visiting scientists
Actions: Promote scientific research on the Bank (conferences, local, national media, and presentations). Provide assistance to researchers (providing logistic support and access to equipment)

Key issue: Work with the commercial fishermen in the management of the fisheries resource.
Actions: Promote the creation of a fisheries association among the fishermen as key stakeholders.

Key issue: Establish sustainable financing mechanisms
Actions: Raise money from fishing permits. Seek structural funding from the Dutch government under the new constitutional relationships.