Brunel, T.

This report presents an overview of the trends in St Eustatius fisheries based on the fisheries data collected on the island during 2012-2018. The fishery on St Eustatius remains mostly conducted by small open boasts with outboard engines. The number of fishing trips carried out by the fleet increased over 2014 peaking in 2015 with roughly 100 trips per months, and subsequently decreased in the following years to an average of 25 trips per month in 2018. 

The main activity is a lobster fishery using traps, also catching a mix of reef fish. This fishery is responsible for nearly 70% of the lobster landings on St Eustatius. The trend in the annual landings in this fishery broadly follows the trends in the fishing effort, with landings reaching 30 tonnes in 2015 and decreasing to 9 tonnes in 2018. Landings of lobsters from the trap fishery show a strong seasonality with higher landings from September to March, and low landings during June-July. The abundance index (derived by modelling the landings per trip) indicates an overall increase in abundance from 2012 to 2017, and an apparent decrease in lobster abundance in 2018. The average carapace length (CL) shows interannual variations without any specific trend, but is on average 95 mm for females and 102.5 for males. This means that an average of 41% of the lobsters are landed below the legal size limit (95 mm). This problem is especially acute for females of which 56% of the landings are of sublegal size. 

The species composition of the bycatch of reef fish in the lobster traps is very diverse, and is dominated by Acanthuridae (Blue Tang, Doctorfish, Surgeonfish), Ostraciidae (Honeycomb and Scrawled Cowfish) and Serranidae (Coney and Red Hind). The trends in the reef fish bycatch in the lobster traps also followed the trend in effort, with values ranging from 1.7 to 9.9 tonnes caught per year. The biomass index calculated from the catch per trip suggests a decrease in fish abundance between 2014 and 2016 and a small increase thereafter. Length frequency data for the main fish species caught in the lobster traps do not show any notable changes over the period studied. 

The second most important fishing activities after trap fishing are scuba diving and free diving. Both activities catch lobster and fish, but while lobster and fish (mainly Coney, Red hind and Lionfish) are in equal proportion in the landings from scuba diving, landings from free diving are largely dominated by lobsters. The lobster abundance index calculated from the catches per trip in free and scuba diving shows an increase from 2012 to 2016, and a sharp decrease thereafter. This is overall the same pattern as seen in trap-caught lobsters. The difference with the trend in the abundance index calculated based on trap data might be explained by spatial and depth differences in the distribution of the fishing effort between those fisheries. Scuba divers also conduct a fishery targeted on conch, representing roughly 40% of the trips. Estimates of the annual conch landings are very variable, and likely to be fairly uncertain due to the lack of information from logbooks in some years. The mean length of the conch landed appears to be stable over time, at 24.5 cm and 23.7 cm for females and males respectively. 

Next to the traps and diving fisheries, different line fisheries are conducted on St Eustatius. A handline fishery on reef fish produced landings between 0.3 and 4.3 tonnes per year in the period 2014-2017, but with much lower estimates in 2018, mainly due to a drop in effort for this year. Large pelagic fish are also caught by trolling, with landings varying between 0.6 and 2.5 tonnes per year. 

Our main recommendations in terms of both management and research and monitoring are as follows: 

- Improve control of and compliance with lobster size-limit regulations. 

- Develop a FAD fishery management plan as part of a St. Eustatius fisheries development plan. 

- Improve port sampling monitoring and subsampling intensity to cover at least one third of the trips dedicated to each fishing metiér. 

- Conduct a closer study on both the Coney and the Red Hind. Do this by combining more intensive port sampling and fisheries independent studies on the distribution and abundance of these species around St. Eustatius. 

Based on traditional knowledge of the Saban fishermen, a spawning aggregation area (SPAG) for the Red Hind (Epinephelus guttatus) and the Queen Triggerfish (Balistes vetula) has long been known at the northeast end of the Saba Bank, locally known as the Moonfish Bank. SPAG’s are very vulnerable to overfishing because these fish aggregations are predictable in space and time. Both are species of special concern throughout the wider Caribbean, due to overfishing. In 2013 a 5-year seasonal closure was arranged that prohibited fishing the Moonfish Bank from the 1st of December to 28th of February, within which, according to local knowledge, mass spawning takes place. The closure ended in February 2018. In this report we provide a preliminary evaluation of the effect of this 5-year seasonal closure on Red Hind and Queen Triggerfish populations of the Saba Bank based on the monitoring of fishes landed in the Saba Port in those 5 years, throughout the year. For both focal species we examined annual differences in the length-frequency distributions and Landings Per Trip (LPT; number of fish landed per fishing trip) from bycatches in both shallow (~30 m) lobster traps and deep (~100 m) snapper trap fisheries, using port landing data from 2011, which is prior to implementation of the closure measure in 2013, until September 2018. 

Our preliminary assessment by means of Generalized Linear Model (GLM) analysis gives no indication of any improvement in LPT or mean size caught for either of the two species examined since the seasonal closure was initiated in 2013. Results even suggest a small but significant decrease in the size of Red Hinds caught as by catch in the lobster pot fishery. This means that, based on the port sampling method used, no significant positive effect on the Red Hind and Queen Triggerfish populations of the 5-year closure can yet be demonstrated. There are many possible explanations for this result, which are presented in the discussion. In particular, there is reason to believe that the current closure area may not be large enough to properly protect the Moonfish Bank SPAG and that there likely are other SPAG’s on the Saba Bank that may also need protection. Therefore, further fisheries-independent research on these and other matters is needed on which basis it may be possible to improve protection so that positive evidence of the effectiveness of the closure may be documented in the future. 

Based on fisheries-independent visual diver surveys in the shallow (~ 20m depth) coral reef zone of the Saba Bank edges in 2011, 2013 and 2015, the current population status of our focal species (in that limited habitat zone of the Bank) is as follows: Red Hinds averaged 118.7 ± 53.5 (ind. ha-1) with a mean size of about 24 cm, while Queen Triggerfish averaged 56.0 ± 37.6 (ind. ha-1) with a median size of about 29 cm (data of 2011, 2013 and 2015 combined). For both focal species, the median size landed in the fishery (Red Hind: about 31 or 33 cm depending on the type of fishery pots; Queen Triggerfish: 34 cm) was considerably larger than the mean size of the population on the reef based on surveys along the available coral reef transects. This is generally to be expected as fishing gears and fisheries typically select for larger individuals. We cautiously suggest that compared to many other areas in the Caribbean (e.g. Bonaire and Curaçao) where the Red Hind and the Queen Triggerfish once were common but now have disappeared, the populations of both these species living in the shallow coral reefs of the Saba Bank still seem relatively healthy in terms of both population density and size-structure. 

Based on experiences elsewhere in the region, there is no question that protection of spawning aggregations is a basic need for sustainable management and fishery production in mass-spawning species. Therefore, our main management recommendation is that the closure should continue. However, to reliably asses the effect of seasonal closure and to further improve protection of the spawning grounds for these species, more intensive and consistent data is needed from port sampling which should also (minimally) include data on sex and maturity of the landed fish, even though such data fall outside the typical scope of routine fisheries port sampling. Most critically, directed fisheries-independent research will be needed to answer several critical questions regarding stock status and when and where spawning aggregations are actually taking place, to improve the effectiveness of seasonal closures of spawning areas of Red Hind and Queen Triggerfish on the Saba Bank.

This report presents an overview of the trends in St Eustatius fisheries based on the fisheries data collected on the island during 2012-2018. The fishery on St Eustatius remains mostly conducted by small open boasts with outboard engines. The number of fishing trips carried out by the fleet increased over 2014 peaking in 2015 with roughly 100 trips per months, and subsequently decreased in the following years to an average of 25 trips per month in 2018.

The main activity is a lobster fishery using traps, also catching a mix of reef fish. This fishery is responsible for nearly 70% of the lobster landings on St Eustatius. The trend in the annual landings in this fishery broadly follows the trends in the fishing effort, with landings reaching 30 tonnes in 2015 and decreasing to 11 tonnes in 2018. Landings of lobsters from the trap fishery show a strong seasonality with higher landings from September to March, and low landings during June-July. The abundance index (derived by modelling the landings per trip) indicates an overall increase in abundance from 2012 to 2017, and an apparent decrease in lobster abundance in 2018. The average carapace length (CL) shows interannual variations without any specific trend, but is on average 95 mm for females and 102.5 for males. This means that an average of 41% of the lobsters are landed below the legal size limit (95 mm). This problem is especially acute for females of which 56% of the landings are of sublegal size.

The species composition of the bycatch of reef fish in the lobster traps is very diverse, and is dominated by Acanthuridae (Blue Tang, Doctorfish, Surgeonfish), Ostraciidae (Honeycomb and Scrawled Cowfish) and Serranidae (Coney and Red Hind). The trends in the reef fish bycatch in the lobster traps also followed the trend in effort, with values ranging from 2.5 to 9.9 tonnes caught per year. The biomass index calculated from the catch per trip suggests a decrease in fish abundance between 2014 and 2016 and a small increase thereafter. Length frequency data for the main fish species caught in the lobster traps do not show any notable changes over the period studied.

The second most important fishing activities after trap fishing are scuba diving and free diving. Both activities catch lobster and fish, but while lobster and fish (mainly coney, red hind and lionfish) are in equal proportion in the landings from scuba diving, landings from free diving are largely dominated by lobsters. The lobster abundance index calculated from the catches per trip in free and scuba diving shows an increase from 2012 to 2016, and a sharp decrease thereafter. This is overall the same pattern as seen in trap-caught lobsters. The difference with the trend in the abundance index calculated based on trap data might be explained by spatial and depth differences in the distribution of the fishing effort between those fisheries. Scuba divers also conduct a fishery targeted on conch, representing roughly 40% of the trips. Estimates of the annual conch landings are very variable, and likely to be fairly uncertain due to the lack of information from logbooks in some years. The mean length of the conch landed appears to be stable over time, at 24.5 cm and 23.7 cm for females and males respectively.

Next to the traps and diving fisheries, different line fisheries are conducted on St Eustatius. A handline fishery on reef fish produced landings between 1.4 and 4.9 tonnes per year in the period 2014-2017, but with much lower estimates in 2018, mainly due to a drop in effort for this year. Large pelagic fish are also caught by trolling, with landings varying between 0.5 and 2.3 tonnes per year.
Our main recommendations in terms of both management and research and monitoring are as follows:
- Improve control of and compliance with lobster size-limit regulations.
- Develop a FAD fishery management plan as part of a St. Eustatius fisheries development plan.
- Improve port sampling monitoring and subsampling intensity to cover at least one third of the trips dedicated to each fishing metiér.
- Conduct a closer study on both the Coney and the Red Hind. Do this by combining more intensive port sampling and fisheries independent studies on the distribution and abundance of these species around St. Eustatius.

The recent status and trends in the Saba Bank fisheries up to and including 2015 port sampling data have been previously reported by de Graaf et al. (2017) and a policy brief has also been written based on those results (Debrot and de Graaf (2018). The purpose of this report is to update recent catch trends in the Saba Bank fisheries with the data from 2016 and 2017.

For the lobster fishery (Panulirus argus), the number of fishing trips (and number of traps set) gradually grew from 2012 to 2015 but has since leveled off. The resulting landings of lobster have shown a similar pattern of increase up to 2015 but have now leveled off at around 70 tons annually. Increasing landings per unit effort indicate that the formerly reduced lobster abundance, which had been declining since 2000 and which had reached its lowest level in 2011, has subsequently increased relatively steadily all through 2017, and now has increased back to levels close to those of 2007. The average size of lobsters taken, continues to be large, which is favourable to gradual stock recovery.

Mixed landings of reef fish in the lobster fishery have fluctuated between 10 and 20 tons annually. The LPUE abundance index in bycatch species also shows a decrease of about 35% from high levels in 2000 and 2007 to lowest levels in 2011, followed by an increase up to 2013, after which landings have levelled off.

In the redfish trap fishery (Lutjanus spp.), the number of trips in the redfish trap fisheries had grown significantly during the period 2012 to 2015. In 2016 effort increased again to 625 trips. In 2017 the exerted fishing effort dropped down to about 350 trips, a level seen last in 2012. The landings of redfish have fluctuated over this period, with lower values in 2012 and 2017 and higher values in 2014 and 2016. The LPUE abundance index shows a decrease by 50% between 2007 and 2011, followed by an increase to slightly higher and constant values between 2012 and 2016, while in 2017 the LPUE abundance index continued increasing. The only snapper for which sufficient data was available, was the silk snapper, Lutjanus vivanus. Average size of the silk snappers landed continued its increasing trend, indicative of gradual stock recovery. The drop in snapper landings, despite the higher LPUE in 2017, can especially be ascribed to the 6-month closed season implemented that year (Graaf et al. 2017).

The overall conclusion is that for both the lobster and redfish stocks, stock status, based on the LPUE index and size-structure trends have continued in developing favorably. Bottom drop longline, pelagic and bycatch landings have remained much less important and have shown no significant new developments.

There are two matters of concern that require follow up. Firstly, the positive prognosis for the snapper “stock” status may partly be based on targeting geographically different stocks as well as different species. Hence the data as collected and analyzed may actually be presenting a too optimistic assessment. To evaluate whether this is actually the case will require more detailed analysis based on individual species, as well as more accurate geographical recording of catches than as currently practiced. The second matter of concern regards the fate of the traps that were in the water on the Bank when the hurricanes Irma and Maria struck the area in September 2017. If trap loss was large, this may lead to higher detrimental impacts of ghost fishing in the coming years.

Caribbean coral reefs have been declining for decades due to a combination of anthropogenic drivers and natural phenomena like hurricanes. The degradation of coral reefs is characterised by, among others, a decline in coral cover, a decline in apex predators (e.g. sharks, large groupers and snappers), a decline in invertebrates (Diadema), and an increase in macro-algal cover. In the past 40 years large-scale shifts from coral-dominated to macro-algal-dominated reef communities have occurred throughout the Caribbean.

Healthy coral reef ecosystems and sustainable coastal fisheries are of utmost importance for the small island economies of Bonaire, Saba and St Eustatius. Bonaire (288 km2) is located in the southern Caribbean and is surrounded by the Bonaire National Marine Park (BNMP) which was established in 1979. The BNMP starts at the high-water mark and extends to 60m depth, covering an area of 27 km . In 2008 two fish reserves (no fishing allowed) and two dive reserves (no diving or snorkelling allowed) were established. In this report we document the 2014-2015 status of the coral reef fish stocks, the coral reef fisheries and the coastal pelagic fisheries. Where possible the current status and trends will be discussed in a historical and wider geographical (Caribbean) perspective. 

Caribbean coral reefs have been declining for decades due to a combination of anthropogenic drivers such as unsustainable fishing practises, pollution, erosion and coastal development and natural phenomena like hurricanes. The degradation of coral reefs is characterised by, among others, a decline in coral cover, three dimensional structure, sharks, large groupers and snapper, herbivorous fish and invertebrates and an increase in macroalgal cover. In the past 40 years throughout the Caribbean large-scale shifts have occurred from coral dominated to macroalgal dominated reef communities.
Healthy coral reef ecosystems and sustainable fisheries are of utmost importance for the small island economies of Bonaire, Saba and St Eustatius. St. Eustatius (21 km2) is located in the north-eastern Caribbean and is surrounded by the 2700 ha St Eustatius National Marine Park (SNMP) which was established in 1996. From 1996 the SNMP included two marine reserves, the Northern Reserve (163 ha; rezoned in 2015 as harbour area) and the Southern Reserve (364 ha), in which no fishing or anchoring is allowed. In this report we document the 2015 status of a range of indicators for the health of St Eustatius coral reef ecosystem and its fisheries. Where possible the current status and trends of the indicators are discussed in a historical and wider geographical (Caribbean) perspective.

Status coral reef: Coral cover declined to a historic low. Dominance of macroalgae is established.The grouper species composition is characteristic for highly fished areas with little management.The status of key herbivorous fish (parrotfish and surgeonfish) biomass is reasonable at best.Using the most conservative survey results (precautionary approach), the overall Reef Health Index scored the reefs St Eustatius as “poor” in 2015

Status fishery: The capacity of the coastal fishery has remained roughly the same over the past 15 years, and possibly even since 1908