Topics in Compan An Med 28 (2013) 151–162

Topical Review

Longline Fishing (How What You Don't Know Can Hurt You) Kevin T. Fitzgerald, PhD, DVM, DABVPa,b,n Keywords: longline fishing albatross dangerous fishing practices threatened seabirds threat to biodiversity conservation a

VCA Alameda East Veterinary Hospital, Denver, CO, USA b Board of Directors, Denver Zoo, Denver, CO, USA n Address reprint requests to: Kevin T. Fitzgerald, PhD, DVM, DABVP, VCA Alameda East Veterinary Hospital, 9770 E Alameda Avenue, Denver, CO, USA. E-mail: kevin.fi[email protected]

Longline fishing utilizes monofilament lines that can be as much as 62 miles long. The line itself is buoyed by Styrofoam or plastic floats. Usually, at about every 100 ft, a secondary line is attached and hangs down from the mainline. The lines are baited with mackerel, squid, or shark meat and have as many as 10,000 hooks. Every 12-24 hours, the line is hauled in, mechanically rebaited, and set back into the water behind the vessel. The baited hooks can be seen by albatross and other seabirds as they are placed in the water or being hauled out. When the birds dive for the bait, they are hooked, dragged behind the fishing boat, and drown. Spectacularly nonselective, longline fishing techniques also hook many other forms of marine life—“bycatch” (sea turtles, seals, dolphins, penguins, sharks, and many other nontarget finfish). It is estimated that 300,000 seabirds (including 100,000 albatross) die on longlines each year. Albatross are among the longest-lived birds. They can live up to 60 years and some species do not start breeding until they are 10 years old. They have a low reproductive rate and many species only breed every other year. In addition, a species like the Wandering Albatross (Diomedea exulans) rears its chicks for an average of more than 270 days. Albatross pair for life and may take years to find a new partner if their mate is killed. Owing to their incredibly low reproductive rate, albatross are particularly vulnerable to longline fishing. Currently, it is believed that 4 albatross drown per 100,000 hooks set. This is more than 400 birds a week. The current mortality rate for adult birds is not sustainable and for some species, the birds are dying faster that they can repopulate. Currently, 19 of the world's 22 albatross species are threatened with extinction. This year longline fishing ships will set 10 billion hooks worldwide. Various mitigation measures (bird-scaring lines, weighted, faster-sinking line, setting lines deeper out of the bird's sight, reduction in the amount of offal discarded from fishing boats, night fishing, and restriction of longline operations from areas where nesting and foraging birds are congregated during the breeding season, among others) have been proposed and attempted. There is no one panacea for the effects of longlining and mitigation efforts are most successful when used in combination. Some of these mitigation measures have shown very promising results. Some experts feel that government legislation, regulation, and enforcement in conjunction with incentives for the fishing industry to incorporate and implement mitigating techniques have the best chance in ameliorating the problem. The public is surprisingly unaware of this wanton and wasteful exploitation of the ocean's resources, and the worldwide demand for seafood continues to rise. Meanwhile, globally, fishermen voice the same complaints: fewer fish, smaller fish, shorter fishing seasons, bizarre developments in their seasonal appearance and dispersal, and fewer overall species seen. These are all the classic signs of overfishing. Each year it is estimated that some 90 million tons of wild fish are harvested from our planet's oceans. Nearly 30 million tons of this is discarded as the incidental bycatch of nontarget species. If international curbs are not placed upon wasteful fishing practices, we are doomed to learn a painful maxim. “The ocean is not infinite.” Veterinarians must become involved in worldwide conservation efforts, acting locally, while thinking globally. & 2013 Published by Elsevier Inc.

Introduction What you don't know doesn't hurt you “Puddn'head Wilson”—Mark Twain For many cultures and civilizations worldwide, fish have traditionally provided a steady supply of available protein. As the population of the Earth has exploded and many developed countries have identified fish as a healthier source of sustenance, international demand for fish has skyrocketed. Commercial fishing ventures in a multitude of countries deal in supply and demand. These commercial fishing enterprises are bound by 3 realities; the actual operational costs of fishing (in terms of equipment, manpower, licenses, processing, etc.), the supply of the target species, and the demand for and price of the target fish set by a world market.1 Like any other business, commercial fisheries must attempt to maximize their profitability and productivity. As a result, modern commercial fishing techniques are a far cry from a worm on a hook at the local fishing hole. Centuries of stalking the

same species, studying their natural history and behavior, and modern sophisticated fish-finding equipment have taken most of the guesswork out of locating targeted species in their largest numbers.2 Many modern fishing techniques are astonishingly nonselective in what is caught and are damaging to the environment at a variety of levels. Compliance by commercial fisheries with local, national, and international laws and agreements regarding quotas, fishing techniques, and illegal activity is difficult to monitor and adherence to these laws at sea is next to impossible to enforce. The problem is demand for fish by virtually the entire global market. People are eating more fish. In the last 50 years, world perperson consumption of fish has gone from 20 lb/y (1960) to 36 lb (2005).1 Even the way we look at fish is skewed. We call them “seafood.” What other species or group of animals has our ultimate goal in its name? The other problem is that of all the tens of thousands of species of fish in the oceans, world demand clamors for only 5 fish: cod, tuna, halibut, salmon, and sea bass (and before that the now somewhat protected swordfish). Industrial fishing

1527-3369/$ - see front matter & 2013 Topics in Companion Animal Medicine. Published by Elsevier Inc. http://dx.doi.org/10.1053/j.tcam.2013.09.006

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with its sophisticated factory ships is only too happy to oblige. As a result, worldwide fishermen voice the same complaints—fewer fish, smaller fish (“no more big ones”), shorter fishing seasons, bizarre developments in their seasonal appearance and dispersal, and fewer species seen. In 1900, the average Atlantic swordfish caught weighed more than 300 lb.1 In 1963, the average swordfish landed was 266 lb and in 1996 the average swordfish weighed just 90 lb. That the size of the animals captured is shrinking and that almost all the fish caught are juveniles are classic signs of overfishing. Despite these observations, wild fish are still being caught in huge numbers. Wild fish harvested from the oceans is estimated to amount to some 90 million tons a year.1 Although we are fast approaching a tipping point with regard to wild fish species, there is still time to do something. Fish do not need us to survive, they reproduce just fine on their own. We need them. Recently, I returned from my third trip to Antarctica. While at sea, I had the opportunity to visit with seamen, researchers, scientists, and oceanographers. In our conversations, they all in different ways drummed home the same message. “The ocean is not infinite.” On my trips, I witnessed many worrisome things; pollution, contamination, retreating ice fields, resumption of Japanese whaling, and factory fishing, and I was discouraged. Nevertheless, we cannot allow ourselves to be pessimistic. There is much that we can do. In this discussion, we focus on one type of commercial fishing, investigate the damage it has caused, and explore what measures can be taken to alleviate its destructive effect. Veterinarians must become integral players in conservation efforts. We are duty bound to safeguard animal life on this planet and this does not stop at the doors of our hospitals. Veterinarians must become stewards and guardians of all life on Earth. We cannot afford to be like Puddn'head Wilson. What we do not know can hurt us more than we can imagine. We must learn to take stock of the world around us.

Longline Fishing The herring are not in the tides as they were of old. The Meditation of the Old Fisherman—W.B. Yeats Aside from pollution and contamination with toxins, commercial fishing has the greatest effect upon marine ecosystems.3 It affects both the life cycle and the habitat of the target species. In the face of smaller catches, greater costs for fuel and operations, and decreasing revenues, the fishing industry has been forced to adopt evermore invasive techniques. With fishing methods falling under greater governmental and international agency scrutiny, techniques like gill netting falling into worldwide disfavor, and a United Nations (UN) ban on drift nets, longline fishing appeared by the early 1980s. By this method, vessels trail a monofilament fishing line, often more than 60 miles long. Every 100 ft or so, a secondary line (called a “gangion” or a “snood”) branches off carrying additional baited, barbed hooks as it dangles. These lines themselves can be up to 1200-ft long. Often, there are as many as 2000 of these secondary branches over the 60 miles that the line stretches. Hooks are typically baited with squid, mackerel, or sometimes shark and a single longline may carry up to 10,000 hooks. The longline is buoyed by Styrofoam or plastic floats. Most of the longline boats have freezer capacity, a small working crew, and can stay at sea for months covering vast ranges of ocean. They know the fish they seek and use sophisticated fish-finding equipment such as sonar and computer-guided imaging to find schools of fish. Every 16-24 hours, they haul in the lines they trail, retrieve their catch, mechanically rebait the hooks, and reset the lines. In 2006, it was estimated that 3 billion longline hooks were set worldwide and in 2012 the number of longline hooks set worldwide was 10 billion.4-6 More than 80 million tons of fish is caught each year through longline techniques.7

The nonselective nature of longline fishing is immediately apparent. This limited selectivity leads to “bycatch,” which is the incidental and unintentional capture of living nontarget species.3,8-10 Each year thousands of seabirds, marine mammals, sea turtles, sharks, and unwanted finfish are caught by longline techniques.3,6,11 Most of this bycatch is discarded with the majority of these unintentionally caught animals dying. Worldwide, a recent estimate of the total marine bycatch discarded was more than 30 million tons per year or about one-third of the yearly total catch.3,4,12 In one study, 149 other species of unwanted finfish were observed to be caught and discarded in 1 week aboard a fishing boat.3 The usual target of longline enterprises are large predatory fish such as tuna, swordfish, Chilean sea bass (Patagonian toothfish), and to a lesser extent halibut, cod, marlin, and snapper. Everything else is discarded as undesirable, usually for economic reasons. Lost fishing gear threatens marine life. Lines can break away and this lost gear continues to function (“ghost fishing”), catching target, nontarget, and protected species alike.3,13-15 Comprehensive data on the effect of ghost fishing is not available but ingestion of and entanglement in discarded human fishing gear has been documented in more than 250 marine species.3,14 It is easy to blame the commercial fishing industry, easy to look for the “smoking gun.” Nevertheless, the blame lies in multiple places. Lack of cooperation among the countries with regard to conservation of ocean resources, lack of incentives of the fishing industry to follow government mandates, lack of a coherent and visionary “ocean policy” by our own government and leaders, ignorance on the part of the public about the dire straits facing both the fishing industry and many species of fish, and the everincreasing demand by the consumer for seafood, all drive and sustain the incredible waste and exploitation being witnessed. The fishing industry is in trouble. As early as 1989, a study by the UN Food and Agricultural Organization estimated that it cost about $92 billion annually to maintain and operate the world's fishing fleets. That year revenue was only $70 billion. The difference was made up mainly through subsidies from governments to commercial concerns.1,16 According to the UN, in the 1990s, the 12-country European Union was spending more than $580 million annually in subsidies to fishing compaies.16 Norway alone pays $150 million a year to its fishermen. Japan has been estimated to be extending nearly $20 billion in credit to its troubled fleets. Why do countries continue to subsidize such a failing proposition? It is because they know it is better to subsidize a faltering industry as in the new world economy there are no jobs for thousands of out-of-work fishermen and boat builders. In addition, the UN further estimates that the world fishing fleet currently is twice as large as what wild ocean stock can support.1 Nations must cease to subsidize such large-scale waste and senseless exploitation. Finally, fishing can have unintended effects on the populations of target species and upon the ecosystems they inhabit. The fishing industry's continual removal of larger, older, and more fertile individuals from the population deplete the best reproducers and reduce a species ability to replenish itself. Not only does it affect the target species but also the food chain which the target is a part of. Depleting a dominant predator species such as swordfish or tuna can cause both competitors and prey species to increase whereas animals that prey upon the swordfish and tuna may decrease precipitously. These increases and decreases in other species can have unexpected effects. Increased discarding of unwanted dead bycatch increases the amount of food for opportunistic scavengers such as crabs, other invertebrates, nontarget fish species, and seabirds. Commercial fishing provides numerous benefits to the nations of the world; food, employment, business opportunities, and nonedible products used in a variety of endeavors, fish meal

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fertilizers, medicines, and supplements like omega fatty acids and vitamins. Governments need to manage programs and maximize the benefits of fishing while minimizing the deleterious effects upon delicate marine ecosystems. Next, we examine the nontarget species most severely affected by longline fishing and what can be done to mitigate the damage of this controversial fishing technique.

Seabirds Albatrosses have survived in the harshest marine environment for 50 million years, more than 100 times longer than our own species. However, these magnificent birds are unable to cope with man-made threats, such as longline fishing. Sir David Attenborough, naturalist … with his cruel bow he laid full low the harmless Albatross. “The Rime of the Ancient Mariner”—Samuel Taylor Coleridge Traditionally, the majestic albatross has been considered a good omen for seamen on the ocean and far away from home. There are 22 species around the world, with 17 of them restricted to the Southern Ocean. They are an engineering marvel, their long narrow wings allow them to catch currents of wind and glide for literally thousands of miles with only occasionally flapping their wings. Albatross are among the largest flying birds, with some species weighing up to 10 kg (almost 25 lb).17 The wandering and royal (or “great”) albatross have some of the largest wingspans of any living bird species, reaching up to 3.5 m (about 11 ft).18 By angling their huge wings and the direction of their flight path, albatross are able to use the variation in air speed and direction of wind currents near the waves to soar over the oceans. This phenomenon is known to physicists as “dynamic soaring.” This type of flight is incredibly efficient and requires less energy from an albatross than sitting on the nest.

Albatross pair for life and may take many years to find a new mate if their partner is killed.17-19 Many birds simply never find a new mate at all. Albatross are extremely long-lived birds that can live for 60 years or more. However, today this extreme longevity is rare. Albatross breed in remote areas but longline fishing, feral cats, and rats are placing great pressure on the world's populations. Albatross have a low reproductive rate, for some species only 1 egg per year and many species breed every other year.17 In addition, albatross chicks are very slow to mature with some species not fledging until they are 10-11 months old. This means that for albatross, only 1 young is produced every 2-3 years. To make it worse, once albatross chicks fledge, they do not return to

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land for many years. For the royal or “great albatross,” they do not return to land for 5 years, but they may not start breeding until they are 10 years old. This incredibly low reproductive rate and delayed sexual maturity means that in some parts of the world environmental pressures are killing albatross faster than they can repopulate. In the North Atlantic, it is believed that 10% of the entire black-footed albatross population is hooked every year.8,23 Albatross are great parents. One of the pair stays with the egg (incubation time is 68-79 days for the Wandering Albatross) while the mate forages and brings back food for the sitting partner. After hatching, 1 parent stays with the chick while the other forages for the pair at the nest. Great wanderers, they have been shown by satellite tracking to fly thousands of miles on their trips to feed their chicks. One Wandering Albatross was seen to fly 10,000 km (6250 miles) in a single trip finding food for its chick and its mate.17 The first inkling that these birds were covering vast distances came when researchers started dyeing birds pink and then recording sea sightings. These birds cover more distance in a day than the ships they follow (up to 1200 miles a day). If the foraging bird is killed during the egg incubation period, the egg dies and the sitting parent often starves.20 If the sitting partner does survive, its body resources may be reduced to atypically low levels affecting both future survival and reproductive performance. All this stress caused by the forced extension of its brood guard shift caused by the death of its partner on a longline. So for every albatross killed actually 3 may be dying. Their natural history and low reproductive rate make them incredibly vulnerable to environmental pressures such as those posed by longline fishing.

With global demand for ocean seafood at an all-time high, hundreds of thousands of seabirds are being killed yearly by the fleets of longline fishing vessels that crisscross the world's oceans.9,10,21-25 While the longlines are being set and placed in the water behind the boats, the birds see the bait, swarm and grab for it, and become impaled on the barbed hooks—either caught in their bill, on their body, or on their wings. They are pulled behind the boat, dragged under the surface, and unable to free themselves, they drown.21 Many seabirds follow ships. They feed off the garbage and offal discarded from vessels. When the longlines are set and placed, owing to their large size, the albatross can dominate the feeding frenzy and win the battle for the morsels of fish and squid (all set on a longline hook). This “smash-andgrab” feeding frenzy thus selects albatross and larger species of birds (petrels and shearwaters) as top victims of longline hooks. Some 300,000 seabirds, including 100,000 albatross, are killed every year by longline fishing.10 One study found 0.04 albatross hooked per 1000 hooks.26,27 This number seems low until it is realized that represents 4 birds per every 100,000 hooks and 10

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billion hooks were set last year. For some parts of the world, and some times of the year, the mortality rate is even higher and in some areas, albatross represent 80% of all seabirds hooked.8,10 One study conducted in New Zealand showed the mortality rate reaching as high as 1.75 birds per thousand hooks. It is estimated that 400 albatross die each week because of longline fishing.19 Albatross are not the only bycatch victims. Worldwide, at least 64 other seabird species are known to have been killed in longline fishing operations.28,29 Many of these species have been listed as threatened. This is a global phenomenon with bird takes happening worldwide. The species victimized vary with location. In the Southern Ocean, it includes albatross (Wandering, Royal, and Black Browed), petrels (White-chinned), and stearwaters.10 In other parts of the world, Northern Fulmars, Black-footed Albatross, and various gulls make up most of the seabird bycatch.23 Larger birds and socially dominant species out compete smaller seabirds when longlines are first set. Smaller species of seabirds have adopted a strategy of staying near vessels even when nothing is being dumped as a method of being there first when longlines are set and garbage is actually discarded. Much of the offal released has fish hooks still in it, which can also hurt the birds if they consume it. In the view of most seabird biologists, ecologists, and oceanic researchers, longline fishing poses the single greatest threat to seabirds worldwide.3 The current mortality rate of these animals, particularly for certain species of albatross, is not sustainable once their incredibly low reproductive rate is considered.30,31

The turtles were taking hooks baited with mackerel, squid, and shark meat. As in other studies, most turtles caught are hooked in the mouth, nearly 83%, with 15% hooked in the esophagus or deep gut.32,33 Another 1% were hooked in the eye and 1% were hooked in the flipper. No numbers were reported for turtles hooked by lost gear (“ghost fishing”) or how many were entangled in lost line. Typically, the fisherman observed did not have time to remove embedded hooks or bring them on board before the line was cut. Hauling turtles impaled with hooks on board generally caused increased tissue damage from embedded hooks. Many turtles drown and die when hooked on deeper lines or when they are caught near a large fish and are unable to swim to the surface to breathe. One study on sea turtles caught by the Spanish longline industry has estimated that 30% of turtles captured die after being released back into the sea.34 If this 30% mortality figure is extrapolated to the rest of the world's longline fishing fleet, the actual number of sea turtles being killed has been grossly underestimated. The longline industry seriously threatens sea turtle species already under severe pressure from a number of other stressors. As more longline hooks are set each year, even greater numbers of turtles can be expected to be taken.

Sea Turtles And the turtles, of course…all the turtles are free, as turtles and, maybe, all creatures should be. Dr. Seuss It is estimated that globally 40,000 sea turtles are caught by longline fishing every year.11 Most of these are loggerhead and leatherback sea turtles. In one study from the Azores, the monthly turtle catch aboard a longline vessel was 0.27 turtles per 1000 hooks baited.32 This means 2.7 turtles for every 10,000 hooks. Most turtles that are hooked are from the largest size classes, which are the turtles making the greatest reproductive contribution to the replenishment and survival of the population. It has been shown that for sea turtles, as for many vertebrate species, growth maintenance of population numbers was most dependent on the survival of large reproducing adults. Longline fishing targets those individuals most necessary for the preservation of the population.

Marine Mammals Oh, weary wee flipperling, curl at thy ease! The storm shall not wake thee, no shark overtake thee, asleep in the storm of slowswinging seas. Seal Lullaby—Rudyard Kipling In addition to seabirds and sea turtles, marine mammals likewise are attracted to the tempting bait on longline hooks.3 Seals, porpoises, and even smaller whales and orca can become entangled in the lines or swallow hooks and drown.3,6 In Hawaii, monk seals have been rescued following longline encounters.35 Longline fishing techniques are thought to be responsible for the death of several thousand marine mammals worldwide every year. Even if the lines are cut, the mortality rate is high for those animals that swallowed hooks or those badly ensnared in tangled line.23 Ghost fishing by lost gear has also been shown to victimize oceanic mammals. In an Australian study, at any time, 500 seals in Tasmanian waters have “collars” of plastic litter or discarded fishing line.27,36 Sharks and Nontarget Fish Species I know up on the top you are seeing great sights but down at the bottom, we, too, should have rights. Dr. Seuss

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In the last 2 decades, shark populations around the world have shown steep declines.37-39 In some parts of the world, shark populations have decreased by as much as 90%.1 It has been estimated that 50,000 sharks are caught in longlines in Australian waters alone each year.36 Although sharks are typically part of the bycatch of unwanted, untargeted fish incidentally hooked by longliners, what is even worse is many of the sharks caught are the victims of “finning.” By this gruesome practice, captured sharks have their fins cut off and then are discarded back into the ocean to die. Shark fins can fetch a very high price owing to the demand in Asia for shark fin soup. A price for a bowl can be as high as $75 in Tokyo. In 1995, the Hawaii-based longline fleet caught 101,773 sharks and approximately 50,000 lb of dried shark fins were landed in Hawaii.3 The absence of such top-of-the-foodchain predatory fish can have serious repercussions on ocean ecosystem dynamics. Despite shark finning and some longline operations fishing specifically for sharks, most sharks captured by longline fishing are discarded. The PEW Institute for Ocean Science has stated “sharks presently caught on longlines are at or below the size at which they reproduce. This makes it unlikely that their populations will recover from their depleted numbers unless there is a reduction in fishing pressure.”3 Studies have shown that shark mortality approaches 97% if they are on the hook for more than 12 hours.40 Typically, the vessels reset the lines only every 1624 hours. Owing to the extreme nonselective nature of longline fishing, nontarget finfish of many species are captured each year in huge numbers. As a result, it is estimated that as much as one-third of the total catch is discarded on account of economic concerns.1,3 One vessel, observed for 1 week, hooked 149 nontarget fish species that were discarded.3 After being hooked and dragged behind the vessel for usually 24 hours, most of these captured nontarget fish are dead when they are thrown back into the sea. Records show that 1000 other nontarget finfish species have been caught by longline fishermen. Solutions It isn't that they can't see the solution. It is that they cannot see the problem. G.K. Chesterton In view of the effects of longline fishing upon seabirds, nontarget species, and a variety of sea life, solutions must be identified to mitigate its tremendous effect. The deleterious effects of this technique of fishing are evident and well documented. At the level it is currently being practiced worldwide, it is not sustainable, and fish populations, numbers of nontarget species, and the industrial fisheries themselves will all crash. It is not too late. If something is done now, animals such as the albatross can be saved. To preserve the wondrous biodiversity of our planet, we must be clever, committed, and courageous. There is a precedent for such global protective actions. In 1993, the UN banned worldwide driftnet fishing on the high seas. This type of fishing and the pervasive nets had precipitated a similar crisis, drowning hundreds of thousands of dolphins, whales, seals, turtles, and other marine species. Unfortunately, the problem is that many of the world fishing fleets replaced their destructive drift nets with the equally damaging longlines. Nevertheless, there are things that can be done to lessen the threat of the terrifically nonselective effects of longlining. In this section, potential methods to reduce bycatch mortality in longline fisheries is examined, along with their individual strengths and weaknesses. The most commonly recommended mitigation efforts to reduce the destructive effects of longline fishing are (1) the use of bird-scaring “tori” lines (“tori” means “bird” in Japanese) and

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streamers; (2) the use of weighted lines that sink faster; (3) thawing the bait (frozen bait floats longer and attracts more birds); (4) dyeing the bait blue to be less visible; (5) setting chutes or funnels below the water (setting the line underwater to begin with); (6) reduction or elimination of garbage and offal from ships (birds have followed ships for centuries attracted to and eating discarded refuse and garbage); (7) fishing at night; (8) area and seasonal closures (avoiding certain areas at sensitive times such as high density foraging areas during the breeding season and during chick care); (9) limiting the seasons and overall time that industrial fisheries could set hooks; (10) development of specific species-selective baits; (11) hook modification to reduce the probability of birds getting caught; (12) water cannon, acoustic deterrents, and magnetic deterrents to reduce the attractiveness of the fishing vessels; (13) giving preferential licensing to fishing companies that utilize mitigation measures; (14) government and international legislation to regulate worldwide longline fishing; and finally, (15) educating the public about these practices and what they are doing to the environment and teaching consumers to learn and pay attention to how their food was raised, caught, or processed. Consumer demand sets the world market price for fish. Teaching the public by labeling longline products “Seabird friendly” or not and other market-based measures could influence industrial fishermen to reduce bycatch mortality. (1) Bird-scaring “tori” lines These bird-scaring lines are positioned over the area behind the vessel where the hooks first enter the water.8,19,23,41,42 The lines extend about 90 m from a high point or pole near the stern of the vessel out to a weighted buoy that drops behind the ship. The line suspends brightly colored UVprotected tubing or streamers spread about every 16 ft. The lines must be heavy and sturdy enough to maintain a near vertical fence in moderate to high ocean wind conditions. Individual streamers must extend to the water so as to prevent more aggressive birds from getting to the fishing line. The principle behind such lines is that the erratic movement of the suspended streamers scares seabirds away from entering the area where the baited hooks of the longline are going into the water. Streamer lines had been shown (although they do not deter all bird species equally) to reduce seabird bycatch anywhere from 30%-25%.42 Extensive testing on fishing boats in Alaska has shown that streamer lines that were deployed in pairs almost totally precluded birds from 40-50 yards of the wake zone.43 Bird-scaring lines were first developed by Japanese tuna fishermen who realized the lines prevented the birds from taking bait meant for the fish. If the streamer lines are placed appropriately and weighted lines are used, the hooks sink immediately behind the boat and the flapping streamers scare the birds away. By the time the hooks are out of the streamer zone, they have usually sunk below the depth that can be reached by most seabirds. Most seabirds only feed within the “seabird zone,” within 1 fathom (6 ft) of the surface. Shearwaters are the exception. They dive deep, they dive often, and they can easily reach 35 fathoms. There is low initial cost and installation for bird-scaring lines. The first few times, setting up can be time consuming but this quickly becomes routine. Paired streamer lines cost, at the time of this writing, less than $300 delivered.19 This is nothing when it is considered that a Southern Bluefin Tuna recently brought $173,600 at a Japanese fish market, enough to equip nearly 6 hundred vessels with bird-scaring equipment. Streamer lines by themselves are not enough to prevent incidental bycatch of seabirds and other nontarget species.23 However, when used in conjunction with other mitigation techniques, they can be highly effective.23,41,42

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(2) Line-weighting techniques Slow-sinking longlines have been shown to hook and drown more seabirds than lines that sink fast.43 Line weighting by itself has been documented in some studies to be superior to types of bird-scaring lines. The concept here is to increase the sinking speed of baited hooks and reduce their exposure time to the seabirds. Usually, as longlines enter the water, they float just below the surface, held aloft by propeller turbulence, wave action, and natural buoyancy of the bait. Depending on vessel speed, the type of gear, and the type of bait, they can remain in this “floating” position for 20 seconds or more and be 30-40 yards astern before they start to sink, thus making it an easy and tempting bait for hungry seabirds. Ideally, longlines should sink the moment they enter the water, sinking out of reach of swarming birds. A study conducted in New Zealand showed that with no line weighting, the longline only sank to a depth of 2-5 m at 100 m behind the vessel, and several seabird species (black-browed albatross and white-chinned petrels among others) were able to dive to this depth and get hooked and captured.43 With effective line weighting (usually about 5 kg every 40-60 m of line), the longline sank to greater than 10 m at 100 m behind the boat with very few scavenging seabirds able to retrieve bait from this depth. This study used manual addition of weights, which is impractical in terms of time and labor as a routine practice.41 More efficient methods of acceleration of line sink rates have been developed, such as integrated line weighting. In this method, beads of lead are woven right into the fabric of the line. Such integrated weight longlines come in 25-g/m, 50-g/m, 75-g/m, and 100-g/m varieties. In a combined study conducted in Australian and New Zealand, the 50-g/m line was shown to perform the best.23 It sank instantly, 2.5 times faster than normal un-weighted line, did not affect fishing efficiency, and was fairly pliant and easy to use. In a 16-day study off the coast of New Zealand, integrated weight longlines caught only 1 seabird during the course of the study whereas 82 birds were hauled on nonweighted longlines during the same time period. There was no difference in the size of fish caught using either line but the weighted version had potentially saved lives of over 80 birds. Field trials off South Georgia utilizing weighted lines with sink rates of 0.2-0.3 m/s gave bird catch rates during daytime in summer as low as night-time rates in winter.23 These studies suggest that weighted longline may be an effective method of reducing incidental bycatch mortality even during times when the birds are most vulnerable. The expense of weighted lines lies in the initial purchase of weighted material (heavier gear, weights, or integrated weighted line) and any ongoing replacement of weights or weighted line lost while fishing. Some fishing industry spokespersons are critical of weighted lines saying that it makes gear too heavy to set and haul, and that as a result, housings and magazines (for storing line, hooks, snoods, and baiting bins in the automated system) would likewise by prohibitively robust and heavy. One alternative to weights every few meters or integrated weighted lines is a weight built or attached to the end of each snood side branch off the mainline. Studies done provide compelling evidence that line weighting is an effective method in reducing bycatch.41,43 Although line weighting by itself is not enough to prevent incidental bycatch mortality, if used in conjunction with birdscaring lines, the effectiveness of this technique has been shown to be considerable.41 (3) Thawing bait Frozen bait floats better and longer in seawater than thawed baits. This gives swarming seabirds additional time to take

the bait and be hooked. Buoyancy problems in bait can be overcome by thawing or by puncturing the swim bladders in bait fish (mackerel, sharks, etc.). Studies have shown that incidental catch of seabirds is reduced significantly when thawed bait is used.41 The fishing industry is resistant to such a move pointing to additional costs (bait thawing racks on the vessels, etc. and using extra weights to compensate for flotation from the swim bladder of bait fish). (4) Dyeing the bait blue In one study, dyeing bait blue and thereby making it less visible to seabirds was effective in lowering overall bycatch mortality.41 In longline fishing, hooks are mechanically baited by an automated system. Bait (usually mackerel, shark, squid, etc.) could be easily and inexpensively dyed during the time it is being replaced on the hooks. However, the effectiveness of this technique does not approach the efficacy of birdscaring lines, weighted lines, or when these 2 techniques are used together.23,41 (5) Below the water setting chutes or underwater line setting The principle underlying this technique is prevention of access by seabirds to baited longline hooks by setting the line underwater. This way birds never see the baited lines. Currently, there is a commercially available underwater setting tube.23 Attached to the stern of the vessel, this setting tube is about 3-m long and extends to about 1.5-m below the surface. It is operated hydraulically on hinges from its sternfacing operational position to a nonoperating, parked position up against the hull. The funnel or setting pipe has a large-enough diameter to allow the line with baited hooks to pass through and exit below the water line. It has a slot running the length of its side to accommodate the external deployment of buoys, weights, etc. A study was done comparing the efficacy of the underwater setting tube with birdscaring lines on fishing boats in the North Atlantic.23 In this and similar studies comparing their efficacy, the underwater setting tube proved no better than bird-scaring streamer lines in preventing incidental bycatch mortality.23,41 In some studies, the tube did not do as well as the streamers in preventing the unwanted capture of seabirds.41 Probably the biggest issue concerning the tube in its present form is whether it is capable of setting a line deep enough to avoid catching birds in all weather conditions and in all stages of the fishing trip (it is known that the stern of fishing vessels rides higher as the trip progresses). Presently, the tubes deliver baited line only 1.5-m below the surface, not deep enough considering the potential sink rate of the gear, the reduction in setting depth in rough seas, and seabird diving abilities—especially in the Southern Ocean, where acrobatic pursuit divers such as the White-chinned petrel are commonly hooked on longlines. The 1.5-m setting simply may not be deep enough, noting that Northern Fulmars commonly have been observed to dive to at least 4-m beneath the surface and Stearwaters to routinely be able to reach at least 20-m deep on dives. In response to the more shallow setting depth of the linelaying tube, underwater setting “chutes” that set the line at a deeper depth (3 m) have been developed.41 To achieve and maintain its setting depth, chute systems depend on a winch or paravane system. Combinations of water injection and venture forces accelerate the passage of baited hooks from the chute. The fishing industry is generally reluctant to universally adopt and support the use of underwater line setting tubes. The general opinion of the tube is that they are too expensive, they are too fragile, and fishermen are not convinced of its superiority over other mitigating efforts such as bird-scaring techniques or weighted lines. As robust and

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sturdy as the tubes are, they take a serious buffeting on their stern mountings in heavy weather and fishermen have concerns about their shelf life and the wisdom of such a major investment in expensive gear that turns out to require a lot of maintenance. The deeper setting chutes may have an advantage as they are flexibly mounted and removed from the water when not in use. With this equipment, it is possible to obtain simple, rapid chute removal, an attractive feature when dealing with longlines jamming, unexpected rough seas, and situations that require rapid vessel maneuvering. This becomes a real consideration when compared with the shallower setting tubes which are more fragile, are permanently attached, and hang off big ships in rough weather. The biggest drawback to this equipment is the initial cost and installation and weather. There is a lot of maintenance on the equipment due to wear and tear. More work needs to be done but if expense could be kept down, underwater setting tubes and chutes potentially could be an effective way of keeping seabirds from baited hooks. However, underwater line setting devices likely would be most effective if not used as a standalone mitigation device but if used in conjunction with other mitigating mechanisms and techniques. (6) Reduction in discarding of additional garbage from fishing vessels Seabirds have followed ocean-going vessels for centuries. Part of this behavior comes from birds being attracted to rubbish and offal (discarded fish waste produced from gutting and processing the catch) regularly released from the ships once the line is hauled in, shortly after the hooked fish are cleaned and processed. Often, the offal is discarded during the time the lines are being reset. In addition, the discarded offal is sometimes on the same side of the fishing boat as where the lines are set.23,41 Furthermore, in hauling in, the hooks may still have their bait on them intact or retain residual bait. During the hauling-in process, birds are attracted to this bait as it is ripped off automatically from the hooks and dropped in the water below where the line is being pulled in. This brings up an important point. It was long assumed that during line setting, the birds are targeting bait on the sinking hooks. The actual target in some cases may be residual bait on the hooks being hauled in, discarded bait being dropped back into the ocean, or the offal released.44 The offal can be dangerous because the discarded fish, fish heads, and by-products of gutting may still contain embedded hooks. The goal here is the reduction of the attraction of vessels to seabirds by reducing the amount of offal, garbage, and rubbish discarded. Any material discarded from fishing boats should be at times or in a way that makes it the least attractive and least available to birds and is least likely to harm them. The problem of garbage and offal discharge is a serious one and is complicated by the fact that more containers for offal and reconfiguring offal discharge systems can prove costly. Solutions for decreasing the harmful effects of discarded offal include restricting offal release to night time, not releasing offal while the lines are being either set or hauled in, and not releasing offal on the same side of the vessel where the line is being set.41 It should be pointed out that in some cases, offal is released well away from the stern to intentionally distract the birds away from the line and its baited hooks. The efficacy of offal- and baitcasting machines that throw garbage, offal, and bait well away from the ship and the longline has yet to be determined in overall reduction of bycatch. Finally, every effort should be made to avoid discarding offal still containing embedded hooks. Methods for offal reduction should be incorporated and used in conjunction with other solutions

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(bird-scaring streamers, weighted lines, setting lines below the surface of the water, etc.) to minimize incidental bycatch mortality of sea life. (7) Fishing at night (night setting) The principle underlying this method is that by setting the hooks during the hours of darkness, it reduces the visibility of the baited hooks in the water. This technique can be very effective. Nevertheless, the effectiveness of this mitigating method can be reduced by the full moon, and it varies between fishing grounds and also according to species of seabird following the ships. Some species of petrel are very efficient night hunters. Furthermore, ships fishing in the higher latitudes encounter summers in which the hours of darkness are severely reduced. This can dramatically affect total hours of fishing each day. In addition, it may inadvertently add costly techniques to assist in maximizing fishing efficiency in a shorter period of time. Smaller costs may also be incurred in making vessel lighting appropriate for the safety of the crew. Finally, imposing night fishing only may affect longline fishing capacity. Overall, this technique is unreliable as fishing seasons do not always coincide with seasons containing maximum hours of darkness. Although night fishing can contribute to a reduction in incidental bycatch, it is another mitigating method that if used only by itself still allows the capture of significant numbers of nontarget species.41 (8) Area restriction and seasonal closures Many seabirds restrict their foraging activities to the immediate vicinity of the breeding colonies during the brooding period.17 Problems arise when longline fishing companies operate near these breeding or brooding sites. Restricting the timing of longline fishing ventures so that they are not in the vicinity of seabird colonies nor do they coincide with breeding and brooding seasons could reduce seabird bycatch at a particularly critical time of the year.26 At South Georgia, the brooding period for the Wandering Albatross (Diomedea exulans) ranges from February 27 to May 11. If longline fishing was stopped here from the end of February to midMay, it could substantially contribute to a reduction in the number of birds hooked.20 Thus, the concept behind this mitigation technique is reduction of longline activity during times of the year when there are high concentrations of breeding, brooding, or foraging birds.41 Owing to the high concentration of birds in these times and their intense foraging behavior for sitting mates and chicks, and as during the period of chick care parental duties limit the distance adults can fly from breeding sites, seabirds are particularly at risk and vulnerable to capture. Although seasonal restrictions are a potentially sound mitigation method for reducing nontarget bycatch, such closures face strong resistance from the fishing industry. Seasonal closures and area restrictions of this type would cause fishing fleets to spend more money on being more efficient in a shorter time and reduce total fishing capacity. Area and seasonal closures could be significantly effective.41 Although forcing the longline fishing fleets to reduce overall fishing efforts in some seasons and implementing national and international regulations requiring longliners to avoid certain areas during sensitive times would definitely contribute to bycatch reduction, this technique too is most effective when used in conjunction with other mitigation options.20,41 (9) Limiting length of fishing seasons Generations of intense fishing for target species have given fishermen a sound understanding of their natural history. Breeding seasons, initiation of schooling behavior and appearance of large schools, and areas where certain fish

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are typically found are all well known and documented. Reduction in the length of time vessels are allowed to fish (reduction in the total number of fishing days) would also limit the number of lines and hooks set in a season.41 The fishing industry is against any such measures as it would diminish fishing capacity and increase costs as crews would attempt to catch the same number of fish in a shorter amount of time. Costs would increase owing to longer shifts by fishing crews, better equipment necessary to increase efficiency of the catch per vessel, and more vessels required to produce the same capacity. If used together with other bycatch reduction methods, limiting the length of the fishing season would certainly have an effect.41 (10) Development of species-selective baits The thought behind this method would be decreasing the palatability of bait to nontarget species such as albatross and turtles while increasing the attractiveness and palatability of baits to target species.40,41 By this approach, species-selected baits would be identified and developed. In one study, an artificial bait was developed for longline fisheries that caught target species, Pacific Halibut (Hippoglossus stenolepsis) and Sablefish (Anoplopoma fimbria) as efficiently as natural bait, while almost eliminating the hooking of nontarget species (e.g., squalid sharks, skates, and rays). Ideally, artificial baits or species-selected baits would be more attractive to target species (increased hooking rates) while less attractive to bycatch species (decreased hooking rates). New baits (both natural and artificial) are constantly being developed and tried, however, their effectiveness has not always been concretely demonstrated. The cost of using artificial baits vs. natural baits might prove prohibitive to the fishing industry.41 Nevertheless, this area shows promise and deserves investigation. As has been demonstrated multiple times however, the most effective way to reduce bycatch in a fishery is to combine several mitigation efforts. (11) Modification in hook type The size and type of hooks used has long been known to influence what is being caught. For turtles, circle hooks have been shown in some studies to be less deadly than the more commonly used “J” hooks.23,32 For seabirds, much promising work has been done regarding hooks. Hooks protected by a pod making it harder for birds and smaller animals to get to the bait, and hooks that do not open until greater depths have been reached are receiving a lot of industry attention. Cost may be a factor in obtaining the more selective, specialized hooks. Still, the concept of developing a hook that reduces the probability of seabirds being caught (owing to it not opening until a greater depth or because it has a less desirable shape) is one that deserves consideration.45,46 If such an effective hook is identified and developed, it could be used alongside other recognized methods to reduce bycatch. (12) The use of water cannon, acoustic deterrents, and magnetic deterrents to scare away seabirds A variety of methods have been employed to deter birds from attacking longlines.23,41 Acoustic deterrents (such as high frequency, high volume, bird distress calls, and gun shots) have been played to birds with low return upon effort.41 Seabirds quickly habituate to loud noises and background noise itself is loud on a working fishing ship at sea. Although the birds may initially be frightened with various loud noises, in a very short time, they ignore them if there is no consequence. Water cannons have been used to conceal the baited hooks using high-pressure water to disturb the sea above the line and to scare the birds. This method seems to be ineffective in preventing birds from attacking the longline.41 Likewise, magnetic deterrents have been utilized to

perturb the magnetic receptors of the birds by creating distracting magnetic fields. There was no indication of the efficacy of this method.41 Although all these techniques are relatively inexpensive, there was no evidence that any of these methods were effective consistently in scaring birds away from the vessels or the lines. (13) The use of preferential licensing to vessels that use mitigation measures It has been suggested that fishing operations that utilize effective mitigation measures to reduce incidental bycatch might be granted preferential fishing licenses.40,41 Employing the use of mitigation methods as an incentive might be an effective way of reducing incidental capture of nontarget species and in developing new solutions to this problem. The scientific community should collaborate and assist the fishing industry in the development of new solutions. The use of incentives such as preferential licensure might be a very effective way to guarantee the use of mitigation measures. The industry would resist this as this method would force the use of techniques that can add considerable additional costs. Nevertheless, programs such as this should be explored as providing fishing operations with incentives to utilize useful solutions and to continue to develop new ones may be the single most effective way to ensure compliance.41 Thus, rewards for good behavior could help stimulate even more research into finding new solutions to the problem of bycatch. (14) Governmental regulation and legislation to police worldwide longline fishing Changing fishing practices (drift netting, longlining, trawling, etc.) can have dramatic effects on populations of both target and nontarget species.3 Management of industrial fishing focuses upon safeguarding commercial fish yield and keeping populations of target and nontarget animals sustainable. Unfortunately, for the industrial fishing industry, regulating action is rarely taken until after a problem has been recognized, and by then, irreversible damage may have already occurred. Currently, the greatest threat from the fishing industry appears to be because of the effects of longline fishing on albatross.19 Mitigation measures are being implemented, but not at a rate necessary to avoid further unsustainable losses to albatross and other seabird populations.30,31 Some researchers feel that the development of efficient mitigation measures alone is insufficient and must be accompanied by governmental implementation and enforcement.40 This would require a combination of efforts including regulation at both a national and international level, cooperation among nations involved, and effective enforcement by agencies and compliance by the fishing industry. Governmental regulation and legislation concerning incidental bycatch is examined in a later section. (15) Public education and public awareness One of the biggest problems surrounding longline fishing is that the majority of the public are totally unaware of the problem. Demand for seafood continues to climb worldwide, particularly for an incredibly small number of species (cod, halibut, tuna, salmon, sea bass, and swordfish).1,2 Market prices for seafood continue to rise. Facing rising fuel costs, decreasing populations of fish, and increased governmental regulations, the fishing industry is forced to continually search for new ways to be more efficient and remain profitable. At some point, the public must learn the fallacy about the infinite ocean and about unsustainable industrial fishing practices that threaten both target fish species and nontarget marine species alike. People must be aware of how the food they eat is grown, captured, and processed. Companies that have good report

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cards with regard to environmental matters should be rewarded whereas those with unfavorable records should be boycotted. These are businesses, they notice sales, they notice the bottom line. Raising public awareness by advertising “albatross friendly” canned tuna or “seabird friendly” fish through product certification and labeling has had positive effects where it has been undertaken. Organizations should be supported that advocate sustainable environmental policies. The public needs to be educated in these matters. Websites such as Monterey Bay Aquarium's Seafood Watch Program (www.montereybayaquarium.org), where it is explained which seafood are endangered and why and what should be avoided, should be consulted.47 It is no sin to not know, but it is a great sin to not learn and remain ignorant. Every effort must be made to educate the public. Public outcry and change in public opinion can influence governments and leaders to acquire the will to undertake political action. Finally, the public must recognize their role in driving the demand for evermore seafood and help develop sound alternatives that are environmentally friendly and deliver reasonable amounts of seafood to our tables. In conclusion, it becomes apparent when all these various mitigation measures are evaluated that there is no single panacea or “magic bullet” to alleviate all seabird and nontarget species incidental bycatch. Rather, the best scenario would involve a combination of the most effective technical methods coupled with incentive-based voluntary measures by the fishing industry and effective enforcement by national and international government agencies worldwide. The best mitigating technologies would be affordable, accessible, and effective. Finally, public awareness of the problem must increase and stimulate responsible political action regulating this industry.

Governmental Regulations and Legislation When men are pure, laws are useless; when men are corrupt, laws are broken. Disraeli Many experts believe that although mitigation measures to reduce incidental bycatch are being developed and implemented, they are insufficient unless accompanied by international regulation and enforcement.1,3,23,40 Worldwide, the efficiency of the fishing industry is increasing, whereas worldwide fish resources available are not. Seabird and nontarget species deaths on longlines are a truly international environmental problem. Developed nations could set an example by the adoption of stricter bycatch regulations. By October 1996, faced with increasing evidence in the worldwide decline in albatross and other seabird populations, the International Union for Conservation of Nature—World Conservation Union (an intergovernmental organization)—adopted a resolution urging nations to both “adopt the goal of eliminating seabird bycatch within longline fisheries” and “implementing sea bird bycatch reduction measures immediately within longline fisheries.”48 The United States supported this action. Previously by international treaty, the Convention for the Conservation of Antarctica Marine Living Resources required all longliners below 3001 south to use bird-scaring lines, set lines at night, add greater weight to lines, and to strategically discharge offal and garbage. Following this lead, the UN Food and Agriculture Organization adopted an International Plan of Action for Reducing Incidental Catch of Seabirds.41 Again, the United States fully supported and voted for this important international protocol. Unfortunately, the protocol is voluntary with no consequences for nonparticipating nations. Moreover, most longlining nations have still not assessed their longline mortality of

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seabirds and have done little if anything to reduce incidental bycatch. Observers placed on all longlining vessels documenting the exact extent of the problem in nonparticipating nations would be helpful. In addition, there are ongoing efforts under the Bonn Convention on the Conservation of Migratory Species of Wild Animals to develop an Albatross Range State Agreement to help protect the birds. In 1997, at the Bonn Convention, all of the world's albatross species were listed as protected. In addition, the data collection and advocacy efforts of Birdlife International's Seabird Conservation Programme has provided helpful information on how best to protect the birds. The United States and the UN must continue to take active, inspired roles in pressing for improved protection of albatross and of all seabirds from the effects of longline fishing. There is a precedent for such international action. In 1993, the UN banned drift net fishing on the high seas worldwide. The nets had caused a huge crisis, drowning hundreds of thousands of dolphins, other marine species, and catching anything in its path. The UN needs to consider a similar action with longline fishing and should also consider economic sanctions against noncompliant countries. The problem is that the most regulations requiring mitigation efforts for bycatch are voluntary and outline no consequences for noncompliance. Proper management regulations must be introduced and enforced. Another complicating factor in the enforcement of regulations upon longliners is that many vessels fly flags of coastal developing states presently exempt from current world fishery management measures. In addition, even more complicating, the nationality of the owner of the vessel is often different from the country flag they fly. In addition, longliners of noncompliant countries have been known to change flags when moving from their own coastal waters to one fishing area and then others. The UN, with help from the United States, must develop a coherent, enforceable policy to control longline fishing if seabird species such as albatross are going to survive. Despite all the sobering studies concerning longlining and the depressing statistics, recently, some evidence has been building that mitigation efforts may make a difference. Some fisheries have enforced strict regulations, resulting in substantial bycatch reductions in recent years. Seabird deaths around South Georgia in the Convention for the Conservation of Antarctic Marine Living Resources zone of the Southern Ocean have declined by 99% since regulations on longline fishing fleets were enforced. Similarly, South Africa achieved a drop of 85% incidental bycatch in its foreign licensed fleet in 2008, when a cap was placed on the number of seabird deaths permitted. In 2009, in the south of Chile, the adoption of modified fishing gear using mitigation measures reduced incidental capture of seabirds from more than 1500 birds a year to close to zero. In Brazil, the voluntary adoption of simple bird-scaring lines reduced incidental capture of seabirds by 56%. More recently, in April 2011, Brazil passed a law requiring the use of strict seabird bycatch measures in their domestic longline tuna fleet. These success stories testify that enforcement combined with mitigation efforts and incentives for compliant fishermen can make a difference. Nevertheless, a recent study documents that techniques used to calculate longline seabird bycatch may seriously underestimate the number of birds taken.44 Possibly twice as many birds are being caught as has been reported. Obviously much more work needs to be done but regulations, legislation, and enforcement must remain an important part of seabird conservation efforts if they are to be successful.

Conclusion I now belong to a higher cult of mortals for I have seen the albatross. Robert Cushman Murphy aboard the brig Daisy (1912)

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Longline fishing is a technique used to capture fish in open waters. A longline is composed of a monofilament fishing line up to 100 km (62 miles) in length with secondary branch lines coming off every 100 yards or so up to 1200 ft long, each baited with thousands of hooks. The lines are hauled in and mechanically rebaited every 12-24 hours. This method of fishing is used in waters off the United States (the North Atlantic and Hawaii), South America, Antarctica, Australia, New Zealand, and Africa. Longlining is used primarily to hook such target fish as cod, tuna, halibut, salmon, sea bass, and swordfish. Longlining is an incredibly nonselective and indiscriminate fishing technique and kills millions of other “nontarget” species each year that get caught on the hooks (“bycatch”). The sheer numbers of unwanted marine species incidentally caught and killed (seabirds, turtles, sharks, marine mammals, and at least 1000 other types of finfish and sea life) is a major cause of concern. Some nontarget species are extremely vulnerable. Many marine birds are relatively long lived when compared with land species. Those that forage far from the coast have low reproductive rates, lay small clutches (usually only 1 or 2 eggs), delay breeding for 5-10 years, have slow chick growth (with a long chick recovery period, and may desert their breeding attempt and leave the nest if conditions deteriorate). The Wandering Albatross (D. exulans), for example, does not breed until about 10 years old, lays 1 egg every 2 years (if successful), and rears its chick for an average of more than 270 days. As a consequence of its low reproductive rate, species such as the Wandering Albatross are particularly sensitive to any increases in adult mortality. It is estimated that more than 300,000 seabirds (mainly albatross, petrels, and shearwaters) are hooked and drown on longlines every year. For some species, losses of this size are not sustainable in terms of their reproductive rate. Worldwide, 19 of the 22 species of albatross are considered threatened with extinction. Longline fishing is the number one threat to the survival of these species. Other factors such as climate change and environmental variation, nest destruction, and disease have been shown to have minimal effect when compared with longline fishing.3 A variety of measures have been developed to mitigate incidental hookings and unwanted bycatch. These methods include bird-scaring lines, weighted fishing line (faster sink rates for hooks), setting lines underwater, reducing offal discarded by fishing vessels, hook modification, and the restriction of longline operations from the vicinity of breeding and nesting sites during the period parents forage for chicks. Many of these measures have been shown to have a positive effect in reducing seabird bycatch mortality, particularly if the more effective techniques are used in combination with one another. It has been suggested that none of these mitigating methods is as effective as mandated governmental policy followed up with enforcement and consequential fines. In addition, various incentives for the fishing industry to use mitigating measures to avoid incidental bycatch have been recommended.41 Currently, although some governmental regulations and legislation have been proscribed, many are voluntary, not all longline operations are compliant, the regulations are difficult to enforce, and there is little international cooperation. The insidious nature of longline fishing is double-edged. Not only is it incredibly damaging to nontarget species and oceanic ecosystems, but also a nearly more insidious aspect of this practice is that the majority of the public are completely unaware of its existence. Certainly almost no one would disagree with the UNs statement that “Fishing practices should be adjusted to minimize the deterioration of sensitive habitats and unacceptable incidental mortality generated by such practices.” The problem is that hardly anyone is aware that such fishing methods are being practiced. The public must learn how its food is raised, captured, and processed. An increase in public

awareness can lead to a change in public opinion and thereby put pressure on leaders and governments to undertake appropriate action. It is not just the public that has been ignorant. Sadly, veterinarians are largely uninformed about longline fishing. Veterinarians should know about this. Wherever there is animal suffering or wanton waste of life, veterinarians should stand up and speak up. The fishing industry, scientists, government officials, and the public must work together to come up with effective solutions for bycatch mortality and continue to promote, protect, and sustain the world's marine resources. It is astonishing when one realizes how linked are the lives of the fishermen, researchers, politicians, consumers, the nontarget species, and the target fish. That link should add to our urgency in solving the problem of longline fishing. Everyone deserves the chance to see a flying, wild albatross, skimming the ocean's waves and gliding to its own rhythm and destiny.

A Glossary of Longline Terms Age Class: The portion of a fish population in a specific age group, often broken out as year classes; Benthic: Occurring at or near the bottom of a body of water; Biomass: The weight or volume of living organisms at a given location and time; Bottom trawl: Fishing net towed along the bottom to catch fish or invertebrates living on or near the bottom; Bycatch: The unintentional capture or mortality of nontarget living marine resources, which may be retained or discarded—generally discarded and includes ghost fishing mortality; Bycatch reduction device: Component of fishing gear intended to lower the amount of nontarget catch (such as the Nordmore Grate used to exclude finfish from shrimp trawls); Cetacean: Whales (large cetaceans) and dolphins (small cetaceans); Community structure: Organization of the group of species occurring in an area and interacting through ecological relationships such as food webs and competition; Crustacean: Predominantly aquatic invertebrates with jointed limbs and an external skeleton (such as crabs, lobsters, and shrimp); Dredge: Fishing gear dragged along the bottom to dig up shellfish (such as oysters, clams, and scallops); Ecosystem: A community of species and their environment, which function and interact as a unit; Finfish: Bony and cartilaginous fish, as opposed to shellfish (such as clams and lobsters); Fishery: The act, process, and industry of catching fish, crustaceans, mollusks, or other aquatic organisms. Fisheries are often targeted at particular species or groups and use specific gear, such as trawls, gillnets, or longlines. A fishery can be for commercial, recreational, subsistence, or aesthetic purposes; Food chain: The succession of organisms in a community through which food energy is passed from prey to predator; Ghost fishing: The capture of living marine resources by lost fishing gear, a component included in estimates of bycatch and total fishing-related mortality; Gill net: Stationary net suspended vertically in the water, designed to intercept and capture swimming fish by their gills; Longline: Fishing gear consisting of a long, heavy fishing line (can be up to 100 km [60 miles] in length) upon which baited hooks and short leaders are attached at regular intervals, deployed at various depths, and designed to attract and hook fish passing by ; Marine mammals: Warm-blooded marine or estuarine vertebrates with live-born young nourished by mammary glands, primarily pinnipeds (seals and sea lions), and cetaceans (whales and porpoises); Mollusks: Shelled invertebrates such as clams and snails, also includes squid and octopus; Offal: The waste or byproducts of the fishing industry (viscera, etc.); Pelagic: Related to species living in the water column and often in open waters, such as mackerels and tuna; Pinniped: Marine mammals such as seals, sea lions, and walruses that use flippers for locomotion; Population: A group of organisms of one species that occurs within some defined area and is to some extent isolated from other groups of the same species; Protected species: Species protected by law, including the Endangered Species Act, which covers all species at risk of extinction; including sea turtles, some marine mammals, and some seabirds. It also includes the Marine Mammal Protection Act (intended to keep marine mammal populations at sustainable levels) and the Migratory Bird Treaty Act (which covers all migratory birds, including several species also covered under the Endangered Species Act); Recruitment: The number or weight of catchable fish added to a stock each year by growth and migration; Seabirds: Birds that feed or spend most of their time in estuaries, coastal areas, or on the ocean (such as gulls, gannets, puffins, murres, and albatross);

K.T. Fitzgerald / Topics in Companion An Med 28 (2013) 151–162 Sea turtles: Large, highly migratory turtles that nest on marine beaches and spend the rest of their lives at sea, primarily in warm waters. Six species occur in U.S. waters; Loggerhead, Green, Kemp's Ridley, Olive Ridley, Leatherback, and Hawksbill. All are listed as threatened or endangered under the Endangered Species Act; Selectivity: Ability of a type of gear to catch a certain size or kind of fish, compared with its ability to catch other sizes or kinds of fish. Longlining and drift netting are nonselective; Stock: A discrete population of a species, such as Gulf of Maine cod ; Target species: The species or species group sought in a particular type of fishing, such as shrimp in the shrimp fishery; may correspond to a particular size range or sex; Turtle exclusion device (TED): Required component of trawl nets in fisheries likely to encounter sea turtles (such as Gulf of Mexico and Southeastern shrimp fisheries); typically consist of a grating to keep turtles from entering the cod end of the net and a trap door through which the turtle can escape; Year class: The portion of a population hatched or born in the same year; Underfished: A fish stock that has the potential to sustain catches higher that those currently taken. The classification is not applied to stocks that are subject to limited catches while rebuilding from overfishing; Fully fished: A fish stock from which current catches and fishing pressure are close to optimum. Categorizing a species as “fully fished” implies that increased fishing pressure or catches (allowing for annual variability) may lead to overfishing; Overfished: A fish stock in which the amount of fishing is excessive or for which the catch depletes the biomass below a specified limit or a stock that reflects the effects of previous excessive fishing. Although both conditions are covered in Fishing Status Reports by a classification of overfished, it is important to recognize the distinction between overfished stocks and overfishing. A management regime may curtail overfishing, but it can still be some time (perhaps many years for some species) before a stock recovers, so a classification of overfished persists; Uncertain: Fish stock may be underfished, fully fished, or overfished, but there may exist inadequate information to determine the status.

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Longline fishing (how what you don't know can hurt you).

Longline fishing utilizes monofilament lines that can be as much as 62 miles long. The line itself is buoyed by Styrofoam or plastic floats. Usually, ...
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