Fish aggregating device

Last updated

A fish aggregating (or aggregation) device (FAD) is a man-made object used to attract pelagic fish such as marlin, tuna and mahi-mahi (dolphin fish). They usually consist of buoys or floats tethered to the ocean floor. Various types of FADs have been employed in the traditional fishing cultures of Island Southeast Asia (especially in the Philippines), Japan, and Malta for centuries. Modern FADs are increasingly being used in modern commercial and sport fishing. [1]

Contents

Echo sounder buoy example model 1 Echo sounder buoy example model 1.jpg
Echo sounder buoy example model 1
An example echo sounder buoy printed circuit board. Echo Sounder Buoy PCB.jpg
An example echo sounder buoy printed circuit board.

Fish behaviour

Fish are fascinated with floating objects, which they use to mark locations for mating activities. They aggregate around objects such as drifting flotsam, rafts, jellyfish and floating seaweed. The objects appear to provide a "visual stimulus in an optical void", [2] and offer refuge for juvenile fish from predators. [3] The juvenile fish, in turn attract predators. A study using sonar in French Polynesia, found large shoals of juvenile bigeye tuna and yellowfin tuna aggregated closest to the devices, at distances of 10 to 50m. Further out, 50 to 150m, a less dense group of larger yellowfin and albacore tuna gathered. Yet further out, to 500m, was a dispersed group of mature tuna. The distribution and density of these groups was variable and overlapped. The FADs were also used by other fish, and the aggregations dispersed after dark. [4]

Types

Drifting FADs float with the currents, are not tethered to the bottom and can be man made, or natural objects such as logs or driftwood. They can include sonar and GPS capabilities so that operators can contact it via satellite to assess associated populations. [5]

Moored FADs occupy a fixed location and attach to the sea bottom using a weight such as a concrete block. A rope made of floating synthetics such as polypropylene attaches to the mooring and in turn attaches to a buoy. The buoy can float at the surface (lasting 3–4 years) or lie subsurface to avoid detection and surface hazards such as weather and ship traffic. Subsurface FADs last longer (5–6 years) due to less wear and tear, but can be harder for fishers to locate. In some cases the upper section of rope is made from metal chain so that if the buoy detaches from the rope, the rope sinks and thereby avoids damage to passing ships. [6]

Traditional FADs

Fish aggregating devices have been traditionally used for centuries by fishermen in Island Southeast Asia, Japan, and Malta. [1]

They are most widespread in the Philippines where traditional FADs are known as payao . Payao are semi-permanent bamboo rafts anchored to the seafloor with rocks. They are usually placed in very deep water, but coastal and shallow-water versions also exist. The rafts are around 4 m (13 ft) long, 1.5 m (4.9 ft) wide, and tapering at one end. Beneath the raft are palm fronds (usually coconut or nipa palm) suspended with weights, usually to a depth of 30 m (98 ft). They have several variants, including simple horizontal bamboo bundles or flat bamboo rafts with attached trailing palm fronds (bonbon), to vertical bamboo bundles with palm fronds on the upper end and "roots" on the submerged end (arong), to double-layered rafts where palm fronds are present both underwater and above-water. [7] [8]

Modern payao have cylindrical, bullet-shaped, or rectangular steel floats that can better withstand rough seas, with cement anchors sunk to depths of up to 5,000 m (16,000 ft) deep. They are harvested using handline fishing, surface trolling, or small-scale purse seining. They are traditionally used to catch pelagic fish (like tuna, mackerel scad, and kawakawa). Payaos can produce catches of up to 200 metric tons of fish. There are thousands of payao anchored in dense networks throughout the Philippines. [9] [7] [8] [10] [1] Payao FADs have been introduced to traditional fishermen in Vietnam, Thailand (where it is known as sung), Fiji, the Solomon Islands, the Federated States of Micronesia, Papua New Guinea, and other countries in Oceania. [7] [8]

In Indonesia, Malaysia, Timor-Leste, and among the Moken people of Myanmar, a very similar traditional method is known as rumpon or roempon in Malay. It uses an anchored bamboo raft supporting a lure line with palm leaves or bundles of grass attached along its length. Fish attracted to the rumpon are caught using dip nets or encircling nets. [7] [1]

In Japan, fishermen use drifting rafts of bamboo bundles to attract mahi-mahi, which are then caught by encircling nets. In Malta, a very similar method (known as kannizzati ) is also used to catch mahi-mahi and pilot fish, using anchored flat cork rafts that are then harvested by encircling nets, long lines, or trolling. [1] In modern times, kannizzati rafts are often made from polystyrene with attached palm fronds harvested from introduced Canary Island date palms ( Phoenix canariensis ). [11] [12]

Applications

Fisheries

Drifting FADs are widespread in the Atlantic, Pacific and Indian Ocean purse seine fisheries. They attract over 1 million tons of tuna (nearly one-third of the global tuna total) and over 100,000 tons of by-catch as of 2005. [13] Skipjack (Katsuwonus pelamis), bigeye tuna (Thunnus obesus) and yellowfin (Thunnus albacares) tuna are the three primary tuna species that FADs target. Other targets include albacore, dolphin fish, wahoo, blue marlin, striped marlin, mako shark, silky shark, whitetip shark, galapagos shark, mackerel, and bonito. [6]

Before FADs, commercial tuna fishing used purse seining to target surface-visible aggregations of birds and dolphins, which were a reliable signal of the presence of tuna schools below. The demand for dolphin-safe tuna was a driving force for FADs. [14] Both recreational and commercial fisheries use FADs.

Increasing FAD since 1990 increased the productivity of the fishing fleet, but has significant side-effects. The average FAD-caught fish is smaller and comes with relatively large bycatch, raising concern about populations of pelagic sharks.

The U.S. state of Hawaiʻi operates 55 surface FADs around its islands to support sport fishing and marine research. [6]

Marine Protected Areas

Blue water FADs can enhance the effectiveness of marine protected areas by retaining fish within MPAs (where fishing is prohibited) long enough to benefit local fish populations. One study reported that even a small number can meaningfully expand populations. [5]

Removal

In the Indian Ocean some NGOs want to reduce the impact of pollution and coral degradation by removing FADs that have drifted onto and damaging corals. Oceanika, a UN registered NGO, launches regular removal missions. [15]

See also

Related Research Articles

<span class="mw-page-title-main">Tuna</span> Tribe of fishes

A tuna is a saltwater fish that belongs to the tribe Thunnini, a subgrouping of the Scombridae (mackerel) family. The Thunnini comprise 15 species across five genera, the sizes of which vary greatly, ranging from the bullet tuna up to the Atlantic bluefin tuna, which averages 2 m (6.6 ft) and is believed to live up to 50 years.

<span class="mw-page-title-main">Albacore</span> Species of tuna

The albacore, known also as the longfin tuna, is a species of tuna of the order Scombriformes. It is found in temperate and tropical waters across the globe in the epipelagic and mesopelagic zones. There are six distinct stocks known globally in the Atlantic, Pacific, and Indian oceans, as well as the Mediterranean Sea. The albacore has an elongate, fusiform body with a conical snout, large eyes, and remarkably long pectoral fins. Its body is a deep blue dorsally and shades of silvery white ventrally. Individuals can reach up to 1.4 m in length.

<span class="mw-page-title-main">Yellowfin tuna</span> Species of fish

The yellowfin tuna is a species of tuna found in pelagic waters of tropical and subtropical oceans worldwide.

<span class="mw-page-title-main">Gillnetting</span> Type of fishing net

Gillnetting is a fishing method that uses gillnets: vertical panels of netting that hang from a line with regularly spaced floaters that hold the line on the surface of the water. The floats are sometimes called "corks" and the line with corks is generally referred to as a "cork line." The line along the bottom of the panels is generally weighted. Traditionally this line has been weighted with lead and may be referred to as "lead line." A gillnet is normally set in a straight line. Gillnets can be characterized by mesh size, as well as colour and type of filament from which they are made. Fish may be caught by gillnets in three ways:

  1. Wedged – held by the mesh around the body.
  2. Gilled – held by mesh slipping behind the opercula.
  3. Tangled – held by teeth, spines, maxillaries, or other protrusions without the body penetrating the mesh.
<span class="mw-page-title-main">Seine fishing</span> Method of fishing with a net

Seine fishing is a method of fishing that employs a surrounding net, called a seine, that hangs vertically in the water with its bottom edge held down by weights and its top edge buoyed by floats. Seine nets can be deployed from the shore as a beach seine, or from a boat.

<span class="mw-page-title-main">Skipjack tuna</span> Species of fish

The skipjack tuna is a perciform fish in the tuna family, Scombridae, and is the only member of the genus Katsuwonus. It is also known as katsuo, arctic bonito, mushmouth, oceanic bonito, striped tuna or victor fish. It grows up to 1 m (3 ft) in length. It is a cosmopolitan pelagic fish found in tropical and warm-temperate waters. It is a very important species for fisheries.

<span class="mw-page-title-main">Pelagic fish</span> Fish in the pelagic zone of ocean waters

Pelagic fish live in the pelagic zone of ocean or lake waters—being neither close to the bottom nor near the shore—in contrast with demersal fish that live on or near the bottom, and reef fish that are associated with coral reefs.

<span class="mw-page-title-main">Drift netting</span> Fishing technique

Drift netting is a fishing technique where nets, called drift nets, hang vertically in the water column without being anchored to the bottom. The nets are kept vertical in the water by floats attached to a rope along the top of the net and weights attached to another rope along the bottom of the net. Drift nets generally rely on the entanglement properties of loosely affixed netting. Folds of loose netting, much like a window drapery, snag on a fish's tail and fins and wrap the fish up in loose netting as it struggles to escape. However, the nets can also function as gill nets if fish are captured when their gills get stuck in the net. The size of the mesh varies depending on the fish being targeted. These nets usually target schools of pelagic fish.

A payao is a traditional fish aggregating device from the Philippines. Payaos are traditionally floating rafts of bamboo anchored to the seafloor, with submerged weighted palm fronds beneath it. They were harvested using handline fishing, surface trolling, or small-scale purse seining. Modern steel payaos use fish lights and fish location sonar to increase yields. While payao fishing is sustainable on a small scale, the large scale, modern applications have been linked to adverse impacts on fish stocks. Payaos have been introduced to fishermen in Vietnam, Thailand, and various countries in Oceania.

<span class="mw-page-title-main">Blackfin tuna</span> Species of fish

The blackfin tuna is a species of tuna in the family Scombridae. It is occasionally referred to as the Bermuda tuna, blackfinned albacore, or deep bodied tunny. They are the smallest tuna species in the genus Thunnus, generally growing to a maximum of 100 cm (39 in) in length and weighing 21 kg (46 lb).

<span class="mw-page-title-main">Fishing techniques</span> Methods for catching sea creatures, especially fish

Fishing techniques are methods for catching fish. The term may also be applied to methods for catching other aquatic animals such as molluscs and edible marine invertebrates.

<span class="mw-page-title-main">Rainbow runner</span> Species of fish

The rainbow runner, also known as the rainbow yellowtail, Spanish jack and Hawaiian salmon, is a common species of pelagic marine fish of the jack family, Carangidae. The species is widespread throughout the tropical and subtropical waters of the world, inhabiting both coastal and offshore areas. The species is the only member of the genus Elagatis, which was created 15 years after its initial description, and is closely related to the amberjacks. The rainbow runner is easily distinguished by its body shape, and the brilliant colouration which gives the fish its name. It is a fast-swimming predator, taking small fish, cephalopods, and a wide variety of planktonic crustaceans. The species reaches sexual maturity around 60 cm (24 in), and spawning takes place at different times, with some populations spawning year round, while others only spawn at certain times of the year. The species is a well known game fish, taken by a variety of fishing methods, and is a well-regarded table fish. Large numbers of the species are taken as bycatch in tuna- and shark-fishing operations and marketed.

This page is a list of fishing topics.

This is a glossary of terms used in fisheries, fisheries management and fisheries science.

Land-based game fishing is a form of big-game sport fishing in which anglers attempt to catch oceanic game fish from shore rather than from ocean-going boats. The locations for such activities are generally rock platforms, though wharfs, jetties and beaches are also common. Some species such as sharks can be targeted in shallow littoral water, however most other species prefer deeper pelagic water, and this limits the areas where these types can be fished from the shore. Tackle used is usually comparable to that used on boats, but some differences are necessary, such as changes in rod length. Different tackle is used according to location and species targeted.

<span class="mw-page-title-main">Fishing industry in the Maldives</span>

The fishing industry in the Maldives is the island's second main industry. According to national tradition in the words of former President Maumoon Abdul Gayoom, "Fishing is the lifeblood of our nation, it is inborn. From the soil on which we live, to the sea around us, it remains an integral part of our existence. Fishing, and our country and its people, [are] one and shall remain inseparable forever." The Maldives has an abundance of aquatic life and species of fish. Common are tuna, groupers, dolphin fish, barracuda, rainbow runner, trevally and squirrelfish and many more. Aside from being of essential importance to the economy, fishing is also a popular recreational activity in the Maldives, not only among locals but by tourists. The islands have numerous fishing resorts which cater for these activities.

<span class="mw-page-title-main">International Seafood Sustainability Foundation</span>

International Seafood Sustainability Foundation (ISSF) was formed in 2009 as a global, non-profit partnership among the tuna industry, scientists and World Wide Fund for Nature. The multistakeholder group states its mission is "to undertake science-based initiatives for the long-term conservation and sustainable use of tuna stocks, reducing bycatch and promoting ecosystem health". Regional Fisheries Management Organizations (RFMOs) are primarily responsible for managing the world's tuna stocks—skipjack, yellowfin and albacore tuna, the species most commonly processed for canned and shelf-stable tuna products, but their parliamentary procedures too often allow the short-term economic and political interests of nations to prevent sustainable measures from being adopted. ISSF works to ensure that effective international management practices are in place to maintain the health of all the tuna stocks.

The Republic of the Marshall Islands has a commercial fishery that targets bigeye and yellowfin tuna using pelagic longline fishing gear. There were 55 longline vessels licensed to fish in the Republic of the Marshall Islands Exclusive Economic Zone (EEZ) in 2011, of which 4 were Marshall Islands-flagged and 51 were foreign-licensed vessels, including 22 Chinese-flagged, 16 Japanese-flagged, 11 Federated States of Micronesia-flagged, and 2 Taiwan-flagged. The Japanese-flagged longliners land their catch in Japan; the other 39 vessels were domestically-based. In 2011, the Marshall Islands longline fleet had reported landings of principal market species of 259 mt of bigeye tuna, 99 mt of yellowfin tuna, 37 mt of blue marlin, 7 mt of black marlin, 4 mt of albacore tuna, and 3 mt of broadbill swordfish. Fresh chilled bigeye and yellowfin tuna is exported primarily to markets in the U.S., China and Canada, and frozen tuna and incidental market species are exported to China and marketed locally.

<i>Canthidermis maculata</i> Species of fish

Canthidermis maculata, also known as rough triggerfish or spotted oceanic triggerfish, is a species of triggerfish native to the tropical and subtropical oceans worldwide. Unlike most triggerfish, they are mostly pelagic.

US FWS <i>Charles H. Gilbert</i> American fisheries science research vessel

US FWS Charles H. Gilbert was an American fisheries science research vessel in commission from 1952 to 1970 in the fleet of the United States Department of the Interior's Fish and Wildlife Service and from 1970 to 1973 in the fleet of the National Oceanic Atmospheric Administration as NOAAS Charles H. Gilbert. She was among the first U.S. fisheries science vessels to explore the central Pacific Ocean in search of commercially valuable populations of fish.

References

  1. 1 2 3 4 5 National Research Council (1988). Fisheries technologies for developing countries: report of an ad hoc panel of the Board on Science and Technology for International Development, Office of International Affairs, National Research Council. Washington, D.C: National Academy Press. pp. 103–110. ISBN   978-0-309-03788-4.
  2. ↑ Hunter, JR; Mitchell, CT (1966). "Association of fishes with flotsam in the offshore waters of Central America". Fishery Bulletin. 66: 13–29.
  3. ↑ Kingsford, M. J. (1993). "Biotic and abiotic structure in the pelagic environment: importance to small fishes". Bulletin of Marine Science. 53 (2): 393–415.
  4. ↑ Josse, Erwan; Laurent Dagorn; Arnaud Bertrand (2000). "Typology and behaviour of tuna aggregations around fish aggregating devices from acoustic surveys in French Polynesia". Aquatic Living Resources. 13 (4): 183–192. doi:10.1016/S0990-7440(00)00051-6.
  5. 1 2 "Research Explores Use of Commercial Fishing Gear as a Conservation Tool". The Nature Conservancy. December 11, 2023. Retrieved 2024-02-19.
  6. 1 2 3 "The FAD FAQ" . Retrieved September 2, 2009.
  7. 1 2 3 4 Jani, Jarina Mohd (2021). "The Status of Artisanal Fish Aggregating Devices in Southeast Asia". In Otake, Shinya; Bortone, Stephen A. (eds.). Modern Fisheries Engineering. CRC Press. ISBN   9781000201321.
  8. 1 2 3 Itano, David; Fukofuka, Siosifa; Brogan, Deirdre (August 2004). The Development, Design and Recent Status of Anchored and Drifting FADs in the WCPO. SCTB17 Working Paper INF–FTWG–3 (PDF). Majuro, Marshall Islands: 17th Meeting of the Standing Committee on Tuna and Billfish.
  9. ↑ Kihara, Yoshifumi (December 1981). "Fishery Based on the Payao Method in the Philippines". Suisan Sekai. 30 (12): 78–84.
  10. ↑ Wesley A. Armstrong and Charles W. Oliver, "Recent Use of Fish Aggregating Devices in the Eastern Tropical Pacific Tuna Purse-Seine Fishery: 1990-1994," Southwest Fisheries Science Center. PDF. Last accessed 20 December 2006
  11. ↑ "Palm fronds used in kannizzati should receive treatments to ward off Red Palm Weevil". Malta Today. 25 July 2011. Retrieved 24 April 2024.
  12. ↑ Azzopardi, Sarah Muscat (8 October 2023). "It's lampuki season! Take a look at this local tradition associated with Malta's small-scale fishing sector". GuideMeMalta.com. Retrieved 24 April 2024.
  13. ↑ "Does fishing on drifting fish aggregation devices endanger the survival of tropical tuna?". Science News . 15 May 2008. Retrieved September 3, 2009.
  14. ↑ Armstrong WA and Oliver CW (1996) Recent use of fish aggregation devices in the eastern tropical Pacific tuna purse-seine fishery: 1990-1994 Administrative report LJ-96-02, Southwest Fisheries Science Center, NOAA.
  15. ↑ "Oceanika calls for industrial fishing vessels to do more to remove FADs in Seychelles' waters".
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.