69th Gulf and Caribbean Fisheries conference
Grand Cayman, November 2016,
The focus of the 69th GCFI conference was on applying fishers’ knowledge and marine science to sustainably manage marine resources. The emphasis was on practical, interdisciplinary, and ecosystem-based approaches, to managing recreational fisheries and marine protected areas (MPAs).
Below you will find a brief overview of the five days of presentations and posters with a distillation of ‘take home‘ messages …
Welcome address: Gina Ebanks Petrie, Director, Cayman Islands Department of Environment
- After a decade of public review the Cayman system of no take areas has been expanded
- Nassau grouper are protected
- Sharks and rays are protected and a shark protection plan is under development
- Cayman has just launched “SIREN“, an iPhone/Android application giving access to a sophisticated database of Marine Park legislation, licenses, permits as well as details of offenders. The application can be used by the public to find out about rules and regulations and to report offenses. Park staff can use the application to get instant access to reports, licenses, permits as well as potential suspects.
Keynote speaker: Dr Brice Semmens, Scripps Institute of Oceanography
Some results from the Grouper Moon Project: this is one of the most comprehensive, long term studies of fish spawning aggregations in the world.
- because fisheries management relies largely on fish catch data, fish which aggregate to spawn are particularly vulnerable to overfishing because fish catch only declines once the fish stocks are severly depleted
- at fish aggregation sites spawning is very highly synchronised and fish are compulsively drawn to spawning sites migrating considerable distances between adjacent sites to spawn. If spawning aggregation sites are depleted fish will stay longer at those sites
- the best spawners are the large old females which can be up to 100 times more fecund that smaller/younger fish. Older fish remain at spawning sites the longest.
- survival of larvae is very temperature dependant: above between 24-26’C there is a 50% reduction in survival rates
Thematic sessions:
Natural and Social Connections
- Following the Deepwater Horizon spill in 2010 in which 200 million barrels of oil were spilled, Sea Grant (www.gulfseagrant) has been synthesizing oil spill science for the general public and decision makers and has produced a number of outreach publications. Oil effects on fish include decreased size, decreased swimming spead, deformities and skin lesions depending on the length of exposure [Dr. Christine Hale]
- REEF is a citizen science programme which started in the 1990s and has gone from strength to strength. REEF has amassed 150,000 surveys in the Caribbean from 8,700 sites. All reports are available on line and raw data files are available on request. This includes meta data [Dr Christy Semmens]
- Cayman Island Shark and Ray Sanctuary received legal protection in April 2015 under National Law. It was preceeded by an 8 year long research project looking at shark species, abundance and population status using citizen science (on line reporting by 1000 members), BRUV stations (1,048 deployments), acoustic tagging (70 sharks), SPOT tags (oceanic white tips and tiger sharks). Socio economic studies indicate the existence value of sharks of $10 million+. Consumptive value is only $1.3 million. Public awareness was a hugely important part of the intitiative and commercial sponsorship includes “white tip beer” lager, sales of which contribute $0.05 per can. Shark Management Plan is now under development and will include a code of practice and information booklet for fishers. [Dr. Rupert Ormond]
- High resolution habitat mapping using satellite images, drop cameras and drones has allowed detailed mapping of near shore waters for entire islands in the Eastern Caribbean, Jamaica and Haiti. Satellite mapping is done with WorldView2 (cost $3000+). They are now experimenting with automated surface rovers equipped with cameras which can be programmed to create photo mosaics for reef monitoring [Dr Steve Schill]
- Drones are being used extensively for coastal and marine survey work as well as for enforcment. Unmanned Aerial Systems (UAS) can be controlled by a mobile device/tablet and fly time is up to 2 hours. UAS Policy and Operations Manuals have been developed for aerial surveys on Antigua and Barbuda. Advice was “start small” and ensure 70% overlap of photos. Advantages: cost effective ($20,000 hardware, $10,000 software), real time data collection, great resolution, not bothered by cloud cover, can access remote areas, hugely popular. Disadvantages: short battery life, payload restrictions and regulations [Dr Kimberly Baldwin]
- Camera sleds are being tested to survey deep water and soft bottom environments ($70,000) [Dr. Bradley Stevens]
- Acropora restoration work in Belize has significantly increased coral cover using nursery grown fragments and outplanting. Survivorship is 89% of the 59,000 corals outplanted to date. Preliminary results indicate that outplanted corals are reproducing. Check out: www.fragmentsofhope.org [Lisa Carne]
- Acoustic telemetry is being used to track small scale movements of juvenile fish (schoolmasters, white grunts, barracuda) to see how them move between adjacent mangroves, back reef and sand areas and how they interact. [Dr Michael Dance]
Understanding and reducing marine debris
First time that the topic of marine debris has been covered at a GCFI meeting
- Problem of plastics in the marine environment is pervasive – 8 million tons of plastic enter the marine environment each year. Microplastics in the marine environment move fast and are ubiquitous. Prevention is the best option. Part of the problem is that solid waste collection and processing throughout the Caribbean is poorly managed. Needs behaviour changes: check out “9 tips for living with less plastic“. [Christopher Corbin]
- Preventing plastics entering the marine environment is key through enhanced recycling and recovery. Check out: Wrap Recycling Action Programme [WRAP]. There are also best practices for containing plastic pellets [Stewart Harris]
- Floating micro-plastics are … scarey! Surface tows using plankton nets have been used to sample open ocean environments in the Caribbean and North Atlantic. Line, pellets and fragements were found. 75% of plastics were fragments of polypropylene and polyethylene [Jessica Donoghue]
- Of the 860 juvenile fish collected from amongst floating sargassum, 10% had plastic in their stomach. Jacks did not contain plastics but 15 other species of fish did have plastics remains in their stomachs including Pygmy Filefish, Sergeant Majors, Bermuda Chub, Filefish and Mahi Mahi. The most common plastics are micro fibers followed by fragments. Polyesther garments can shed up to 1900 microplastic fibers per wash !!! [Dr Frank Hernandez]
- Studies from Grenada looked at microplastics in commercially exploited fish (Red snapper, Red hind, Mutton snapper, Barracuda, Blue Runner, Mahi mahi and Yellow fin tuna). Of 34 fish sampled only one did not contain plastic. [Michelle Taylor]
- A pilot study on Trinidad looked at ways to reduce marine litter at major cultural events. Focus was on encouraging party goers to use bins and working with event organisers. Celebrities were recruited as litter champions [Nakita Poon Kong]
- In Florida volunteers were asked to collect 1 litre water samples from the marine environment and trained in how to filter samples and test them for plastics. Samples were allowed to stand for a week and then passed through a 0.45 micron filter. Material was viewed under a microscope and tested with a hot needle. Of the water samples taken 90% contained microplastic, some contained over 50 items. The most common plastics were microfibers. Volunteers took a pledge to reduce plastic use including not using straws, disposable shopping bags and single use beverage containers. Check out: www.plasticaware.org.
- Fish trap loss in Florida is a major source of marine debris leading to ghost fish traps, entanglement and introduction of monfilament line. Trying to encourage fishermen to only use as many traps as they need to reduce losses. [Thomas Matthew]
- NOAA has a Marine Debris programme coupled with competitive grants addressing prevention, removal and research into marine debris. Citizen science programmes include monthly beach surveys of 100m of beach looking for items larger than 2.5cm. There is an online toolbox with tutorials, photo ID, database and data templates and much more. Check out the Marine Debris Toolbox. [Amy Uhrin]
- Discussion amongst panelist identified a number of gaps:
- science is not being translated for decision makers and the general public
- there are serious public health issies
- little knowledge about the life cycle of marine debris and its toxicology
- sources of microplastics need to be identified
- prevention is key!
Understanding and managing pelagic sargassum
- Check out: sargassum.forum@gmail.com
- Sargassum events occured in 2011, 2014 and 2015. From desk studies it seems as though sargassum was blown east out of the Sargasso Sea. This theory is supported by wind data, drifters etc. [Libby Johns]
- Studies of various species of sargassum (S.natans III, S.natans XIII and S.fluitans III) and their associated epifauna indicates that there may be more than one source of the sargassum weed during events. [Amy Suida]
- Productivity studies looking at nitrogen isotopes in sargassum indicate that the addition of nitrogen into marine systems may be fuelling sargassum events. In Florida nitrogen is no longer a limiting nutrient [Brian Lapointe]
- Sargassum events effect the West coast of Africa, Brazil and the Lesser Antilles in the Caribbean. Both Africa and Brazil are areas where sargassum consolidates and grows. It seems that sargassum productivity may be linked across the Atlantic with the west coast of Africa ‘communicating’ with Brazil and vice versa. [Donald Johnson]
- Management recommendations and best practices have been developed to deal with sargassum events. Current wisdom indicates that whenever possible nature should be left to run its course and sargassum should be left in situ where it will be incorportated into the sand and provides ecosystem benefits. Removal from shorelines should only be considered where the quantity is overwhelming, beaches are heavily used or there is a public health risk. If sargassum has to be removed the least damaging method is by hand with hand rakes and wheelbarrows. Mechanised rakes are good (mechanised buckets are bad) and sargassum should be sifted to remove sand before it is trucked away. Advice is not to remove sargassum when it is floating off shore and that deflection barriers and booms do not work – they get fouled quickly and are difficult to anchor. Check out: Sargassum Management Brief. Communicating with the public throughout the sargassum event is key. [Dr Hazel Oxenford]
MPA science and management
- TEEB study in the Turks and Caicos islands have helped them to identify ecosystem threats, services, beneficiaries and funding sources. Basic management of their 35 MPAs is estimated to cost US$ 1.9 million / optimum management is estimated to cost US$ 2.6 million/year – meaning that they need to increase their income by 0.8-1.6% [Dr. John Claydon]
- TEEB study in the Cayman Islands is nearing completion and will include damage assessment and identifying sources of funding for conservation [Stijn Schep]
Lionfish research
- There are really encouraging results from recent studies with lionfish FADs which can be used to capture lionfish. Designs vary from a pvc frame with a surrounding net which can be pulled up as the FAD is removed from the water to dome traps and something resembling a purse trap. Need to work out optimal design and soak time. Good for deep water sites and sandy bottom. Being tested with fishermen in Belize and Aruba. [Dr Steve Gittings]
- Annual lionfish tournaments on Cayman seem to have been successful at removing large numbers of lionfish particularly as it forces participants to visit unculled sites. Collaboration with local restaurants with cook outs. They have removed 15,000 lionfish. There are prizes for the largest fish, smallest fish, most lionfish and heaviest catch – all fish must be despined. [Bradley Johnson]
- On Aruba studies have looked at how to create a sustainable commercial fishery with the goal of reducing lionfish populations by 75%. A tournament in 2014 in which 29 divers removed 532 lionfish was used to calculate catch per unit effort. It is believed that there are 1.8 million lionfish on Aruba spread of 100 km2 and that this could support 10 commercial divers. [Raven Walker]
- Acoustic tagging of lionfish have shown that they prefer reef habitats and are most active at dawn and dusk. Diver estimates of lionfish numbers are believed to be low. [Ben Binder]
Fishers Forum
VEMCO workshop