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To provide background information on the most important concepts of this research, this chapter describes the basic description of lionfish biology and ecology, a description of the Saba Bank fisheries and associated policy and the history and current state of lionfish awareness and eradication programs in the wider Caribbean area.

2.1 Description of lionfish biology

The two most commonly knows

species in the lionfish (Pterois) genus are the P. miles and the P. volitans (see Figure 4). ‘’Pterois’’ has its origin in the Greek word for ‘’feathered’’.

‘’Miles’’ has its origin in the Latin word for ‘’soldier’’ and ‘’volitans’’ is again Greek, meaning ‘’flying’’.

Although two separate species, they appear similar. The only obvious difference is found within the number of dorsal and anal fin rays.

The P. miles has ten dorsal and six anal fin rays and the P. volitans has eleven and seven respectively (Schultz, 1986).

Lionfish are native to the Indo-Pacific

region. P. miles mainly occupies the Indian Ocean and the Red Sea area while the P. volitans is more focussed in the pacific region and Australia (Schultz, 1986; Schofield, 2009). Since the early nineties of the twentieth century the two species have been introduced to the Western Atlantic and Caribbean regions (Biggs, 2009). They are described as passive hunters, relying heavily on their camouflage with bands of red, white and creamy colours covering its body. They have got prominent pectoral fins, used as wide fans to corner their prey. Asides from being ferocious predators with capabilities to eat almost any organism smaller than them they also resist being predated upon by possessing multiple venomous spines on their dorsal, pelvic and anal fins, numbering up to 18 in total (Bellis, et al., 2012).

However not lethal, contact with these spines causes serious injury and discomfort to humans. This feature is part of the reason why the consumption of lionfish is still looked upon suspiciously.

2.2 Description of Saba bank fisheries

About eight to ten fishing vessels are active on Saba, supporting about 30 people directly with employment and income (Toller & Lundvall, 2008; De Graaf, Brunel, Nagelkerke, & Debrot, 2017). The two main fisheries on Saba are both trap-based, one focusses on the West-Indian spiny lobster and the other on deep-water redfish, mainly consisting of snapper species such as blackfin (Lutjanus buccanella), yellow-eye (Lutjanus vivanus) and the vermillion snappers (Rhomboplites aurorubens) and the grouper red hind (Epinephelus guttatus) (see Figure 5) (Toller & Lundvall, 2008). Most fishermen practise both types of fisheries and have their own traps. Lobster traps are deployed in the shallow flats of the bank, and often catch a diverse variety of smaller reef fish species as well. The

Figure 4. Lionfish external anatomy (Rolling Harbour, 2019).

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redfish traps are deployed on the deeper slopes of the bank. For lobster fisheries the main type of bait used are pieces of cowhide. To enhance aggregation, fishermen tend to leave one lobster in the trap when it is redeployed again. In redfish fisheries, most fishermen use Cololabis saira, or as it is commonly referred to, ‘’Japanese bait’’ imported from Taiwan, as well as pieces of undesired bycatch saved from previous fishing trips for this purpose.

Lionfish has been reported as bycatch in the recent years, especially in the deeper redfish traps. It amounts to about 1 lionfish per 1 to 2 redfish traps hauled (De Graaf, Brunel, Nagelkerke, & Debrot, 2017). However, from time to time huge numbers of lionfish are being caught on a single fishing trip, while at the same time days can go by when none are caught whatsoever (Anonymous fishermen, pers. communication, July 2019).

The lobster fishery is the most economically significant. Around 2008, approximately 0,84 lobsters were caught per trap-haul and a total of 83 kilograms per trip with a total value of $1.3 million a year.

Bycatch of smaller reef fish amounted to $68.700 per year (Toller & Lundvall, 2008). According to De Graaf, Brunel, Nagelkerke, & Debrot (2017), there have been no signs of overfishing. Redfish fisheries haul approximately 4,5 kilograms of per trap-haul and 132 kilograms of redfish per trip. Bycatch amounts to approximately 12 kilograms a trip. The value of the redfish is about $289.000 a year. The bycatch value a year amounts to $15.502 a year. The fleet makes an avergae of 3,7 fishing trips per day, which amounts to a projected 312 fishing trips a year for redfish (Toller & Lundvall, 2008).

For the sake of sustaining healthy fish and lobster stocks Saba’s fisheries are being monitored continiously. Monitoring happens through various methods, such as daily short interviews with the fishermen to assess their daily catch, area of fishing and methods of fishing. Size measurements of the catch and inventarisation of the species composition happen on a weekly basis. The most extensive form of monitoring takes place on board of the fishermen’s vessels where all catch is measured and recorded while the fishermen haul their traps. The advantage of this type of monitoring is that even immediately discarded bycatch can be measured and recorded, resulting in a full catch measurement.

2.3 Lionfish eradication programs in the Caribbean

One example of how other islands deal with the lionfish invasion is found in the southern Caribbean, on the island of Bonaire. Bonaire has developed their own lionfish eradication program, which has been adopted by the neighbouring island of Curacao two years later. Bonaire started to prepare

Figure 5. The four species usually referred to as ‘’redfish’’ and which show up most in the redfish pots. From A to D:: yellow-eye snapper (L. vivanus), red hind (E. guttatus), blackfin snapper (L. buccanella) and vermillion snapper (R. aurorubens) (Williams J. , et al., 2013a); (Willams, et al., 2013b); (Williams J. T., et al., 2013c); (Patil, 2019).

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already in 2009 before the actual arrival, which was in 2010. A new spear fishing legislation was passed on in 2010 and, with proper training, volunteers, dive operators, scientists and residents started to participate in the lionfish eradication (Carballo-Cárdenas & Tobi, 2016). Comparisons between fished and unfished areas revealed a significant difference in lionfish density (De León, et al., 2013). Lionfish, however, persist not only in the shallows where the limited depths allow for scuba divers to practice spear fishing. A lot of deeper areas further from the shore are left untouched by spear fisheries.

Lionfish is being consumed on Bonaire on a small scale and consumption is promoted, especially to ensure continuation and expansion of the spear fishing program (Albins & Hixon, 2013).

Other islands have also put effort into lionfish hunting and have tried to combine this with consumption. The Bahamas and Bermuda had programs in 2005 and 2006 in which fishers, both recreational and commercial, were trained in spearing lionfish (Wilms, 2015). The short-term results were positive, but in the long-term a continuing dedication from individual spear fishers is required and that tends to be problematic (Carballo-Cárdenas & Tobi, 2016).

In 2010 in Belize, in the eastern Caribbean, the immediate response by the authorities was to promote the removal of lionfish by fishermen and dive operators by giving a $25 cash reward for every individual caught (Majil, 2010). Around 2011 a demand did exist among the tourists in Belize for lionfish meat, but no restaurant served it consequently as fishermen were hesitant because a guaranteed market for selling could not be established and buyers needed a reliable supply. What became clear is that a central handling facility was needed to provide support for both suppliers and buyers. When a major buyer appeared from the U.S.A. it gave the confidence to establish a fishing cooperative giving support to buyers and sellers and the Northern Fisherman’s Cooperative began to stockpile lionfish for bulk export. This also resulted in a higher supply of lionfish for local consumption at home and restaurants (Chapman, 2014). A five-steps market-based approach through commercial fishers to control lionfish in Belize was developed afterwards (Blue Ventures, 2017).

In the U.S. Virgin Islands research has shown that consumers are willing to pay for lionfish, especially when they know the environmental concerns surrounding lionfish. Also, the maximum price consumers are willing to pay matches the price fishermen would accept for their catch (Simnitt, House, Larkin, Tookes, & Yandle, 2018). A commercial lionfish market seems to be plausible in the U.S. Virgin Islands. The principles of ‘’willingness to pay’’ and ‘’willingness to accept’’ will return later in this report.

An example of an actual trap study like this one is found in Bermuda, where the Department of Environmental Protection has been conducting experiments using modified lobster pots to attempt to catch lionfish selectively (Pitt & Trott, 2015). The researchers tested eight different funnel types and different kind of baits, as well has shading the traps. What they found is that for low relief habitats the structure of the cage alone deemed enough as bait, and using dead bait only increased the amount of bycatch. Escape gaps seems to have significantly decreased bycatch of smaller finfish. Another one of the findings was the importance of identifying lionfish hotpots in getting high catch rates. Asides from the trap study, Davis (2016) investigated the market potential of lionfish in Bermuda, and if consumption of the lionfish is a viable measure to control the population in Bermuda’s waters.

According to the study, which interviews were conducted with the fishermen, consumers and the restaurants, the willingness of the consumers to eat lionfish is present at large, as well as the ability of chefs to prepare the fish. However, no selective lionfish fishery exists yet and restaurants can not and will not sustain a permanent presence of lionfish on the menu. Similar results came from Del Carmen Carrillo-Flota & Aquilar-Perera (2017), who investigated the potential of human consumption of the red lionfish in Quintana Roo, Mexico. All stakeholders they questioned, in this case

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fishermen, restaurant owners and fish consumers, showed high willingness to taste and consume lionfish.

There is currently no lionfish eradication program on Saba. Large-scale spear fisheries are hard to establish due to the rough nature of Saba’s waters and its steep slopes under the sea’s surface.

2.4 Change in attitude towards lionfish consumption

Attitude towards lionfish has been changing substantially since the invasion began, and consumption seems to be a viable option in provide some measure of control on the population. In order to have any measurable effect, the consumption of lionfish must be taking place on a sufficiently large enough scale across a wide range of areas (meaning whole of the Caribbean). This can only be achieved by establishing a market and a complementary supply chain for lionfish which extends further than just the inconsistent catching and selling of lionfish locally.

Problems have existed and still do exist with establishing such a market. Awareness about the seriousness of the lionfish invasion and it associated socio-economic and ecological effects amongst the inhabitants (and potential consumers) of the Caribbean region is important.

Small- and large-scale outreach communication programs across the Caribbean have been carried out in recent years to promote the capture and consumption of lionfish. This is often accompanied by advertisements for a delicacy ready to be discovered and includes workshops on how to safely handle lionfish. The Reef Environmental Education Program (REEF), the National Ocean and Atmospheric Administration (NOAA) and the Gulf and Caribbean Fisheries Institute (GCFI) organized a such a workshop in 2013 to investigate and identify the challenges a large-scale harvest and distribution of lionfish as a mean to control the invasion. The workshop participants concluded that a lionfish market is feasible and should be promoted. Also, local control is effective to mitigate the impacts of invasive lionfish at this scale (Bogdanoff, Akins, & Morris, 2014). Consuming lionfish as an approach to control the species is also supported by its high nutritional value, with n-3 fatty acids values higher than most commonly consumed native marine fish species (Morris, Thomas, Rhyne, Breen, & Akins, 2011).

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