Trolling is a method of fishing

Fishing

Fishing is the activity of trying to catch wild fish. Fish are normally caught in the wild. Techniques for catching fish include hand gathering, spearing, netting, angling and trapping....

 where one or more fishing line

Fishing line

A fishing line is a cord used or made for angling. Important parameters of a fishing line are its length, material, and weight...

s, baited with lures

Fishing lure

A fishing lure is an object attached to the end of a fishing line which is designed to resemble and move like the prey of a fish. The purpose of the lure is to use movement, vibration, and colour to catch the fish's attention so it bites the hook...

 or bait fish

Bait fish

Bait fish are small fish caught for use as bait to attract large predatory fish, particularly game fish. Species used are typically those that are common and breed rapidly, making them easy to catch and in regular supply. Examples of marine bait fish are anchovies, halfbeaks such as ballyhoo, and...

, are drawn through the water. This may be behind a moving boat, or by slowly winding the line in when fishing from a static position, or even sweeping the line from side-to-side, e.g. when fishing from a jetty

Jetty

A jetty is any of a variety of structures used in river, dock, and maritime works that are generally carried out in pairs from river banks, or in continuation of river channels at their outlets into deep water; or out into docks, and outside their entrances; or for forming basins along the...

. Trolling is used to catch pelagic fish

Pelagic fish

Pelagic fish live near the surface or in the water column of coastal, ocean and lake waters, but not on the bottom of the sea or the lake. They can be contrasted with demersal fish, which do live on or near the bottom, and reef fish which are associated with coral reefs.The marine pelagic...

 such as salmon, mackerel

Mackerel

Mackerel is a common name applied to a number of different species of fish, mostly, but not exclusively, from the family Scombridae. They may be found in all tropical and temperate seas. Most live offshore in the oceanic environment but a few, like the Spanish mackerel , enter bays and can be...

 and kingfish

Kingfish

-Fish:* King mackerel Scomberomorus cavalla* Kingcroaker Menticirrhus spp.* Narrow-barred Spanish mackerel Scomberomorus commerson * White croaker Genyonemus lineatus * Cobia Rachycentron canadum...

.

Trolling can be phonetically confused with trawling

Trawling

Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net that is used for trawling is called a trawl....

, a different method of fishing where a net

Fishing net

A fishing net or fishnet is a net that is used for fishing. Fishing nets are meshes usually formed by knotting a relatively thin thread. Modern nets are usually made of artificial polyamides like nylon, although nets of organic polyamides such as wool or silk thread were common until recently and...

 (trawl) is drawn through the water instead of lines. Trolling is used both for recreational

Recreational fishing

Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival....

 and commercial fishing

Commercial fishing

Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often pursue fish far into the ocean under adverse conditions...

 whereas trawling is used mainly for commercial fishing.

Trolling from a moving boat involves moving quite slowly through the water. This can be accomplished with the use of a special trolling motor

Trolling motor

thumb|250px|A 12 volt electric trolling motor mounted on a 8 foot [[inflatable boat]]A trolling motor is a marine propulsion system consisting of a self-contained unit that includes an electric motor, propeller and controls, and is affixed to an angler's boat, either at the bow or stern...

. Multiple lines are often used, and outrigger

Outrigger

An outrigger is a part of a boat's rigging which is rigid and extends beyond the side or gunwale of a boat.In an outrigger canoe and in sailboats such as the proa, an outrigger is a thin, long, solid, hull used to stabilise an inherently unstable main hull. The outrigger is positioned rigidly and...

s can be used to spread the lines more widely and reduce their chances of tangling. Downrigger

Downrigger

A downrigger is a device used while fishing using the trolling method, which places a lure at the desired depth. A downrigger consists of a three to six-foot horizontal pole which supports a cannonball by a steel cable . A clip, also known as a "release" attaches a fishing line to the cannonball...

s can also be used to keep the lures or baits trailing at a desired depth.

Outriggers and downriggers

Outrigger

Outrigger

An outrigger is a part of a boat's rigging which is rigid and extends beyond the side or gunwale of a boat.In an outrigger canoe and in sailboats such as the proa, an outrigger is a thin, long, solid, hull used to stabilise an inherently unstable main hull. The outrigger is positioned rigidly and...

s are poles which allow a boat to troll multiple lines in the water without tangling. A boat which trolls enough lines can simulate a school of fish

Shoaling and schooling

In biology, any group of fish that stay together for social reasons are said to be shoaling , and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling . In common usage, the terms are sometimes used rather loosely...

.

Downrigger

Downrigger

A downrigger is a device used while fishing using the trolling method, which places a lure at the desired depth. A downrigger consists of a three to six-foot horizontal pole which supports a cannonball by a steel cable . A clip, also known as a "release" attaches a fishing line to the cannonball...

 are devices used while trolling to keep a bait or lure at the desired depth. In practice, fish swim at different depths according to factors such as the temperature and amount of light in the water, and the speed and direction of water currents. A downrigger consists of a one or two metre horizontal pole which supports a weight, typically about three kilograms of lead, on a steel cable. A clip called a "line release" attaches the fishing line to the weight, and the bait or lure is attached to the release. The fishing line is reeled in by a spool powered either by manual cranking or by an electric motor. Using a downrigger can be hazardous. For example, man-made reservoirs can contain submerged trees and other structures beneath the surface which downriggers can snag.

Paravanes

Paravane (water kite)

]The paravane is a towed winged underwater object—water kite. Paravanes have been used in sport or commercial fishing, marine exploration and industry, sports and military. The wings of paravanes are sometimes in a fixed position, else positioned remotely or by actions of a human pilot...

 (underwater kites) are sometimes used as depth controlling devices, particularly in commercial tuna fishing operations. These kites have various shapes, such as arrowhead paravanes, flexi-wing paravanes, and bi-wing paravanes.
The devices can place the lure or bait at designated depths and positions; and in this way multiple devices can be towed at the same time without the devices and bait interfering with each other.

"Spreaders" allow multiple baited hooks or lures to be trolled from a single line. There are many inventive spreader designs, such as devices which cause the baited hooks or lures to move in helical patterns, in a sophisticated emulation of the schooling behaviour of a group of fish.

Baits and lures

To be effective, trolling baits

Fishing bait

Fishing bait is any substance used to attract and catch fish, e.g. on the end of a fishing hook, or inside a fish trap. Traditionally, nightcrawlers, insects, and smaller bait fish have been used for this purpose...

 and lures

Fishing lure

A fishing lure is an object attached to the end of a fishing line which is designed to resemble and move like the prey of a fish. The purpose of the lure is to use movement, vibration, and colour to catch the fish's attention so it bites the hook...

 must have the visual ability to attract fish and intrigue them with the way they move through the water. Most trolling lures are designed to look and behave like dying, injured, or fast moving fish. They include:

• Surface lure
  Surface lure
  A surface lure is a fishing lure designed to waddle, pop, lock, drop, pulse, twitch or fizz across the surface of the water as it is retrieved, and in doing so imitate surface prey for fish such as mice, lizards, frogs, cicadas, moths and small injured fish....
  
  s, also known as top water lures. They float and resemble prey that is on top of the water. They can make a popping sound from a concave-cut head, a burbling sound from "side fins" or scoops or a buzzing commotion from one or several propellers.
• Plugs are also known as crankbaits. These lures have a fishlike body shape and as they troll through the water they make various movements caused by instability due to a scoop under their heads.
• Swimbait
  Swimbait
  Swimbaits are a loosely defined class of fishing lures that imitate fish and tend to be distinct in design from a typical crankbait.Swimbaits are usually different from crankbaits by the way they generate lure action. Some are rubber "paddle tail" lures that appear to swim when the tail flutters...
  
  , a minnow-like soft plastic bait that is reeled like a plug. Some have swimming tails.
• Spoon lures resemble the inside of a table spoon. They flash in the light while randomly wobbling or darting due to their shape.
• Spinnerbait
  Spinnerbait
  A Spinnerbait refers to any one of a family of fishing lures that get their name from one or more metal blades shaped so as to spin like a propeller when the lure is in motion, creating varying degrees of flash and vibration that mimics small fish or other prey...
  
  , pieces of wire bent at about a 60 degree angle with a hook on the lower end and a flashy spinner mechanism on the upper end.

Trolling baits and lures are either tied with a knot, such as the improved clinch knot

Improved clinch knot

The improved clinch knot is a knot that is used for securing a fishing line to the fishing lure, but can also affix fishing line to a swivel, clip, or artificial fly.-External links:* * *...

, or connected with a tiny safety pin-like device called a "snap" onto the fishing line which is in turn connected to the reel. The reel is attached to a rod. The motion is of the lure is made by winding line back on to the reel

Reel

A reel is an object around which lengths of another material are wound for storage. Generally a reel has a cylindrical core and walls on the sides to retain the material wound around the core...

, by sweeping the fishing rod, jigging movements with the fishing rod

Fishing rod

A fishing rod or a fishing pole is a tool used to catch fish, usually in conjunction with the pastime of angling, and can also be used in competition casting. . A length of fishing line is attached to a long, flexible rod or pole: one end terminates in a hook for catching the fish...

, or by trolling behind a moving boat. Lures can be contrasted with artificial flies

Artificial fly

An artificial fly or fly lure is a type of fishing lure, usually used in the sport of fly fishing . In general, artificial flies are the bait which fly fishers present to their target species of fish while fly fishing...

, commonly called flies by fly fishers

Fly fishing

Fly fishing is an angling method in which an artificial 'fly' is used to catch fish. The fly is cast using a fly rod, reel, and specialized weighted line. Casting a nearly weightless fly or 'lure' requires casting techniques significantly different from other forms of casting...

, which either float on the water surface, slowly sink or float underwater, in imitation some form of insect fish food. However some flies, such as the trolling tandem streamer fly

Trolling tandem streamer fly

A trolling tandem streamer fly is a style of fishing fly designed to be fished behind a moving boat. Trolling is a form of fishing where the fisherman sits or stands in a moving boat and allows his lure or bait to swim in the water. The Trolling Tandem streamer fly is made of 2 or more hooks tied...

, are designed for trolling behind a moving boat.

As an example, marlin

Marlin

Marlin, family Istiophoridae, are fish with an elongated body, a spear-like snout or bill, and a long rigid dorsal fin, which extends forward to form a crest. Its common name is thought to derive from its resemblance to a sailor's marlinspike...

 lures are typically 7-14 inches or more long with a shaped plastic or metal head and a plastic skirt. The design of the lure head, particularly its face, gives the lure its individual action when trolled through the water. Lure actions range from an active side-to-side swimming pattern to pushing water aggressively on the surface to, most commonly, tracking along in a straight line with a regular surface pop and bubble trail. Besides the shape, weight and size of the lure head, the length and thickness of skirting, the number and size of hooks and the length and size of the leader used in lure rigging all influence the action of the lure: how actively it will run and how it will respond to different sea conditions. Experienced anglers fine tune their lures to get the action they want.

Specialized lures made specifically for trolling swordfish

Swordfish

Swordfish , also known as broadbill in some countries, are large, highly migratory, predatory fish characterized by a long, flat bill. They are a popular sport fish of the billfish category, though elusive. Swordfish are elongated, round-bodied, and lose all teeth and scales by adulthood...

 use plastic glow sticks.

A pattern of four or more lures can be trolled at varying distances behind the boat. Lures may be fished either straight from the rod tip ("flat lines"), or from outriggers.

In addition to attaching a lure to the fishing line, an oval piece of metal (often hammered or curved for reflective purposes) called a dodger is often used to attract fish from greater distances. Lures designed for trolling with downriggers include metal "spoons" that are often decorated with colour tape, and plastic or rubber "squids" with various colours.

A daisy chain is a chain of plastic lures which have no hooks. Their purpose is to function as teasers which attract a school of fish closer to the lures that do have hooks.

Trolling speed

Baits and lures are typically trolled at speeds up to 9 knots, though speeds up to 15 knots can be used, particularly when boats are travelling to different fishing areas. The speed at which the lure is pulled through the water impacts on the fishing success. The optimum trolling speed varies with different species of fish, with weather conditions and the time of year, and other conditions. Chinook salmon

Chinook salmon

The Chinook salmon, Oncorhynchus tshawytscha, is the largest species in the pacific salmon family. Other commonly used names for the species include King salmon, Quinnat salmon, Spring salmon and Tyee salmon...

 can be successfully trolled at higher speeds than more docile lake trout

Lake trout

Lake trout is a freshwater char living mainly in lakes in northern North America. Other names for it include mackinaw, lake char , touladi, togue, and grey trout. In Lake Superior, they can also be variously known as siscowet, paperbellies and leans...

. For these reasons fishermen use devices that accurately track speed. Trolling motor

Trolling motor

thumb|250px|A 12 volt electric trolling motor mounted on a 8 foot [[inflatable boat]]A trolling motor is a marine propulsion system consisting of a self-contained unit that includes an electric motor, propeller and controls, and is affixed to an angler's boat, either at the bow or stern...

s calibrate speed more accurately than large outboard motors. Trolling plates are also used with larger motors to slow the boat to the desired speed, although some anglers experience mixed results with plates.

Trolling can be effective at surprisingly low speeds. Kayaks

Kayak fishing

Kayak fishing is fishing from a kayak. The kayak has long been a means of transportation and a means of accessing fishing grounds. Kayak fishing has gained popularity in recent times....

 fitted with a deck-mounted bracket for holding a rod can be paddled to troll effectively for salmon.

Recreational fishing

In marine environments trolling is used in big-game fishing

Big-game fishing

Big-game fishing, often referred to as offshore sportfishing, offshore gamefishing, or blue-water fishing is a form of recreational fishing, targeting large fish renowned for their sporting qualities, such as tuna and marlin.-History:...

 to catch large offshore or open-water species such as tuna

Tuna

Tuna is a salt water fish from the family Scombridae, mostly in the genus Thunnus. Tuna are fast swimmers, and some species are capable of speeds of . Unlike most fish, which have white flesh, the muscle tissue of tuna ranges from pink to dark red. The red coloration derives from myoglobin, an...

 and marlin

Marlin

Marlin, family Istiophoridae, are fish with an elongated body, a spear-like snout or bill, and a long rigid dorsal fin, which extends forward to form a crest. Its common name is thought to derive from its resemblance to a sailor's marlinspike...

. Saltwater angler

Angler

Angler may refer to:* A fisherman who uses the fishing technique of angling*Angler * The angler, Lophius piscatorius, a monkfish* More generally, any anglerfish in the order Lophiiformes* Angler , a Marvel Comics supervillain...

s also troll for inshore species

Coastal fish

Coastal fish, also called offshore fish or neritic fish, are fish that inhabit the sea between the shoreline and the edge of the continental shelf. Since the continental shelf is usually less than 200 metres deep, it follows that pelagic coastal fish are generally epipelagic fish, inhabiting the...

 such as bluefish

Bluefish

The bluefish , called tailor in Australia, is a species of popular marine gamefish found in all climates. It is the sole species of the Pomatomidae family....

, kingfish

Kingfish

-Fish:* King mackerel Scomberomorus cavalla* Kingcroaker Menticirrhus spp.* Narrow-barred Spanish mackerel Scomberomorus commerson * White croaker Genyonemus lineatus * Cobia Rachycentron canadum...

 and various jacks

Carangidae

Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...

.

Rock fishermen

Rock fishing

Rock fishing is fishing from rocky outcrops into the sea. It is a popular pastime in Australia and New Zealand. It can be a dangerous pastime and claims many lives each year, although this may improve as more fisherman wear life jackets.-Dangers:...

 can use an umbrella rig as a method of trolling without using a boat. Typically, an umbrella rig consists of four plastic neon green lures with a lead dragging behind. An additional lure is attached to the lead. Only the lure behind the lead need have hooks attached because this lure can appear to a stalking fish as a wounded or sick laggard in a school

Shoaling and schooling

In biology, any group of fish that stay together for social reasons are said to be shoaling , and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling . In common usage, the terms are sometimes used rather loosely...

, making it a more likely target.

A pattern of multiple baits or lures can be trolled at varying distances behind a boat. Lures can be fished straight from the rod tip (flat line), or from outriggers. Purpose designed sinkers exist to control the trolling depth on freshwater lakes.

Freshwater anglers can also find trolling effective. Recreational fishermen can successfully troll lakes and reservoirs for salmon

Salmon

Salmon is the common name for several species of fish in the family Salmonidae. Several other fish in the same family are called trout; the difference is often said to be that salmon migrate and trout are resident, but this distinction does not strictly hold true...

 and trout

Trout

Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water...

. It can be the method of choice for catching the elusive muskie

Muskie

Muskie may refer to:*Ed Muskie, American politician*Muskellunge, freshwater fish native to North America...

, and a useful technique for catching walleye

Walleye

Walleye is a freshwater perciform fish native to most of Canada and to the northern United States. It is a North American close relative of the European pikeperch...

, black bass

Black bass

Micropterus , is a genus of freshwater fish in the sunfish family of order Perciformes. The type species is M. dolomieu, the smallmouth bass...

 and striped bass

Striped bass

The striped bass is the state fish of Maryland, Rhode Island, South Carolina, and the state saltwater fish of New York, Virginia, and New Hampshire...

. For light and medium freshwater gamefishing, any reasonably robust casting or spinning rod can be used as a trolling rod. Effective trolling rods should be fairly stiff with a relatively fast action, since "whippy" slow action rods are frustrating to troll with.

Commercial fishing

Commercial trolling vessels catch fish by towing astern one or more trolling lines. The trolling lines are fishing line

Fishing line

A fishing line is a cord used or made for angling. Important parameters of a fishing line are its length, material, and weight...

s with natural

Bait fish

Bait fish are small fish caught for use as bait to attract large predatory fish, particularly game fish. Species used are typically those that are common and breed rapidly, making them easy to catch and in regular supply. Examples of marine bait fish are anchovies, halfbeaks such as ballyhoo, and...

 or artificial baited

Fishing lure

A fishing lure is an object attached to the end of a fishing line which is designed to resemble and move like the prey of a fish. The purpose of the lure is to use movement, vibration, and colour to catch the fish's attention so it bites the hook...

 hooks trailed by a vessel near the surface or at a certain depth. Several lines can be towed at the same time using outriggers to keep the lines apart. The lines can be hauled in manually or by small winches. A length of rubber is often included in each line as a shock absorber. The trolling line is towed at a speed depending on the target species, from 2.3 knots up to at least 7 knots. Trollers range from small open boats to large refrigerated vessels 30 meters long. In many tropical artisanal fisheries

Artisan fishing

Artisan fishing is a term used to describe small scale low-technology commercial or subsistence fishing practices. The term particularly applies to coastal or island ethnic groups using traditional techniques such as rod and tackle, arrows and harpoons, throw nets and drag nets, and traditional...

, trolling is done with sailing canoes with outriggers for stability. With properly designed vessels, trolling is an economical and efficient way of catching tuna

Tuna

Tuna is a salt water fish from the family Scombridae, mostly in the genus Thunnus. Tuna are fast swimmers, and some species are capable of speeds of . Unlike most fish, which have white flesh, the muscle tissue of tuna ranges from pink to dark red. The red coloration derives from myoglobin, an...

, mackerel

Mackerel

Mackerel is a common name applied to a number of different species of fish, mostly, but not exclusively, from the family Scombridae. They may be found in all tropical and temperate seas. Most live offshore in the oceanic environment but a few, like the Spanish mackerel , enter bays and can be...

 and other pelagic fish swimming close to the surface. Purpose built trollers are usually equipped with two or four trolling booms raised and lowered by topping lifts, held in position by adjustable stays. Electrically powered or hydraulic reels can be used to haul in the lines.Drawing (FAO)
Commercial trolling for tuna is more successful near offshore banks than in open water areas, and is also enhanced in the vicinity of a fish aggregation device (FAD).

Historically, in Alaska, hand hook and line trolling were used to catch king and silver salmon in salt water. This method required minimal gear-boat, lines and hooks—and was used to catch fish that were still feeding in open water before returning to spawn. Trolling was very successful in southeast Alaska and historically the catch was used by the fresh and mild-cured fish packing industries. Power boats located near feeding grounds conducted most of the trolling. Each boat had four to ten lines, extending from tall poles hung outboard when fishing; each line carried several hooks, with heavy lead sinkers and spoons or baits as lures. Trolling lengthened the fishing season, allowing fishermen to fish in early spring before spawning runs.