Fisheries Training Course * Hand Outs

FISHERIES

TRAINING COURSE

HAND OUTS

IMPROVE FISHERY OPERATION

Gadhdhoo, Maldives

NOV. 29TH –DEC. 5TH 2009

CONTENTS

COURSE TOPIC PAGE

1 SAFETY AT SEA 3

2 VHF MARINE RADIO COMMUNICATION 12

3 ECHO SOUNDERS / FISH FINDERS 19

4 GPS 22

5 TUNA BEHAVIOUR 26

6 SEABIRDS 32

7 SEA SURFACE TEMPERATURE SST 37

8 STRATEGIES FOR FISHING HIGH MOVING SURFACE SCHOOLS 41

9 SEAMANSHIP 45

SAFETY AT SEA

1. Main causes of distress at sea:

. Engine failure . Disorientation . Insufficient fuel . Accidents . Lack of seamanship skills . Natural conditions like heavy weather etc.

Recommended safety items for every vessel whose length is 25 feet or more with cabin accommodation and capable of night fishing.

(a) A fix-mount compass.

(b) A fix-mount VHF marine transceiver.

(d) At least two fire extinguisher affixed in an accessible area in the cabin.

(e) A portable flashlight with spare bulb.

(f) At least 6 distress flares suitable for use at night and daylight.

(g) At least 2 working bilge pumps and one spare.

(h) Full navigation light – Port, Starboard, Stern, Bow, and Anchor.

(i) One all-round (360 Degrees) red fishing light mounted at least 36 inches above the anchor light.

(j) A life raft or dinghy capable of carrying all persons on board.

(k) Engine spares to include the following: impellers, fan belt, fuel and oil filters, and fuses.

(l) Repair tools to include pipe wrench, spanners, screwdrivers, vice grip etc.

(m) A mooring anchor and anchor rope appropriate to the vessel.

(n) A fixed mount global positioning system (GPS) receiver.

(o) One radar reflector mounted over the top cabin.

(p) A First Aid kit.

(q) At least two batteries- one for starting and one for auxiliary equipment and lights with changeover switch.

OPTIONAL EQUIPMENT

(r) A class II Emergency Position Indicating Radio Bacon (EPIRB)

(s) A Vessel Monitoring System (VMS) Transponder.

(t) A Single Side Band (SSB) HF Marine Transceiver.

Distress Flares and Pyrotechnics are a vital part of the safety equipment of every fishing vessel

Flares comes in three types –

1. Arial or Parachute flares, which ignite after a rocket has carried them skyward; 2. Handheld flares, which create an intense bright red flame; 3. Smoke flares, which have a plume of orange smoke that is highly visible from a searching aircraft.

Any flare is only useful if it can be seen by someone who can give help or alert others. Because each flare burns only for a short time, you should try to maximise the chances of your flare being seen. There are some simple things you can do to ensure your distress signal is as effective as possible.

There are three main types of flares, with different options available for each type:

Orange smoke – effective as a line of sight distress signal for daytime use only.

Red handheld – effective as line of sight distress signal by day and night, and very bright, with a good visibility range. These are very visible from an aircraft, and burn for up to 60 seconds.

Red parachute or rocket – capable of attracting attention in daylight for up to 10 miles, with a night-time range of up to 40 miles. The rocket launches the flare up to 300m and the flare burns for 40–60 seconds as it slowly descends under the parachute.

ENSURE YOU'RE FLARE READY

. Read and understand the firing instruction(s) for your flares before you need to use them, as you will not be able to read the instructions in a distress situation at night, when emergencies often occur. . Store your flares in a waterproof container, or in a dry designated area below deck – and make sure passengers and crew know where they are and how to use them. . Check the expiry date of your flares regularly, and replace flares before they expire. . Dispose of your date-expired flares appropriately (see disposal of old flares). . You should only fire flares when a boat or aircraft is seen, and you should wait until they are at the closest point to your location before firing them. Do not use all your flares at the sighting of an aircraft or boat, they may not see your flares, and you will have to use flares again at sighting of another aircraft or boat. . Always hold the flare to leeward outside your boat when firing. Flares burn with extreme heat, and can easily damage your boat if used incorrectly. . Fire parachute flares downwind – never into the wind – preferably at a 15–20 degree angle off vertical.

LASER RESCUE FLARES - NON-PYROTECHNIC

These up-to-the-minute devices offer a simple and effective way of pinpointing your position to a rescue ship or airplane searching for you. The laser "torch" emits a fan-shaped beam which is pointed at the target and moved slowly back and forth across it. The rescue crew will see a flashing red light which they will be able to home in on.

Rescue Laser flares and lights have a number of advantages over pyrotechnic flares for guiding rescuers to the casualty:

1. Longer in-use life. A typical white pyrotechnic flare, a one-off device, lasts for less than a minute whereas the Rescue Laser Flares and Lights last for hours. Whilst this depends on the weather and the 7

amount of ambient light, in clear conditions and no ambient light the laser devices can be seen out to 20 miles (30 miles in the case of the Rescue Laser Flare Green) by night. By day they are visible out to 3 miles.

2. Location. Rescue Laser flares and lights can be used to illuminate reflective materials such as those on oilskins and life buoys out to a range of 1 mile. 3. Ease of use. Having a simple twist method of switching on and off, laser flares and lights are easy to use. 4. Safety Rescue Laser flares and lights are battery powered and are not a fire hazard. They are much safer to use than a pyrotechnic flare and they can be carried by air. 5. No Hazardous materials to be disposed of after they expire.

Sound Signals Bells, whistles, and horns are some devices used to create distress sound signals.

Other Visual Signals Flags are still used to inform others that you are in trouble. There are code flags which are widely-recognized as signals that indicate distress. A distress flag is orange in color with black square and black ball.

LIFE JACKETS

All fishing vessels MUST have onboard, one life jacket for each person. Life jackets must be stored in an easy accessible area.

No matter how you slice it, almost any boating accident imaginable has a predictable outcome – you in the water fighting for your life. Unless you are wearing a life jacket, your survival chances are marginal.

The best case scenario would be falling overboard without sustaining an injury, and being quickly recovered by a person remaining in the boat, or by 8 a nearby boater. In almost every other scenario, surviving a boating accident that resulted in being ejected from the boat without a life jacket would depend upon a quick rescue.

Nine of ten drowning victims may have survived a capsizing or fall overboard if they had been wearing a life jacket. By wearing a life jacket you increase the chances of surviving. Think of it another way: without a lifejacket, how long can you tread water while waiting for rescue? What if you were injured? The major reason why most fishermen forego wearing life jackets while fishing is a comfort issue, hence the reason why artisanal fishermen just keep their life jackets stored away onboard.

APPROPRIATE LIFE JACKET / PDF FOR OFFSHORE FISHING VESSELS

Fire Prevention and Fire Safety

Fire is very dangerous for vessels at sea. Fishing vessels use and carry lots of things that can cause fires. Once a fire starts on board a fishing vessel at sea it can be very hard to put out. You need to do everything you can to keep your vessel afloat and seaworthy.

Every vessel should have regular fire drills. Practicing what you have to do is the best way to remember it.

Important points for all crew

. Know and look out for fire risks. . Know what fire equipment is held on board. . Know how and when to use all the fighting equipment. . Know how to contain a fire on board. .

Flammable hazard: A flammable hazard is something that could ignite a fire, or something that burns easy

Flammable hazards - Every vessel at sea has a large number of Flammable Hazards on board. These include:

Things that can ignite or start the fire

. heat and sparks from electrical switches, motors, tools and leads . cooker flames . cigarettes and matches or lighters

Things that can give the fire fuel to burn

. diesel fuel . gas . cleaning chemicals . rags with oil or chemicals on them . hydraulic oil

General Fire Prevention

There are two main things you can do on board a vessel to prevent fires

 Keep the vessel tidy - good housekeeping is important  Everyone on board must think ahead and try to identify fire risks during normal day to day operation of the vessel. 10

Here are some specific flammable hazards to look out for. On every vessel there will be other fire risks that are not on this list. Think carefully about your vessel and any other things you can do to prevent fires.

 Ensure no one smokes on board the vessel when taking on fuel.  Make sure all leaks in pipe-lines, fittings and on engines are repaired immediately.  Store flammable products separately and tidily.

LP Gas. Many smaller vessels have LPG gas bottles for cooking.

 Ensure bottles are stowed in an area that they are least likely to be damaged.  Gas bottles must be installed on the exposed weather-deck. Salt air and water will corrode the bottles, so it is best to keep them covered, ensure there is good ventilation to stop fumes building up.  Regularly check hoses and fittings for deterioration.  Install a simple gas detector/alarm.

Cooking fryers, elements and oils. Fires often start on board vessels in the galley. They can start when crew members leave equipment turned on but leave the galley area. To reduce the risk of a galley fire:

 Ensure a smoke detector is fitted.  Lock gas bottles shut when leaving vessel.

Rags. Rags are regularly used to wipe up oil or fuel spills and then tossed into nearby container.

 Dispose of oily rags in metal bin with a lid or sealed air tight bag.

A CLEAN AND TIDY VESSEL IS AN EFFICIENT AND SAFE VESSEL! CLUTTER AND RUBBISH CREATE HAZARDS!

 Clean up slippery decks.  Mop up spills as soon as possible.  Fish slime, etc should be flushed from the deck frequently.  Secure loose gear up of the deck. No ropes or lines should be left strewn on deck.  Keep decks as clear as possible at all times.  Keep equipment, ropes, fish bins tied or stowed up off the deck.  Heavy objects should not be left loose or swinging.  Water-hoses should be coiled and hung on brackets.  Hatch covers should be neatly piled out of passageways when the hatches are open.  Hatches should not be left partially opened or concealed with a tarpaulin.  Don’t leave a hatch open for longer than you have to.  Supplies and fish boxes carried on deck should be covered, if necessary, and securely lashed.  Stow items at main deck level or below. Do not stow heavy items high on vessel as it will affect the Centre of Gravity making the vessel unstable.  Don't store gear in passageways. Keep walkways and passages clear.  Store sharp objects in galley or on deck (knives, gaffs, etc) safely.  Keep quarters neat and orderly.  Stow personal gear properly.  Fire extinguishers should be properly located and never used as coat racks.  Keep a bolt or wire cutter (or knife) on board to cut lines or gear that is tangled or needs to be cut away quickly.  Don't hang unattended towels or wash cloths above the stove to dry

VHF MARINE RADIO COMMUNICATION

Marine VHF Radio

A VHF Marine Radio is a device that is a combined Transmitter and Receiver that receives and transmits in the Marine VHF band. It shares a common antenna and power supply

VHF stands for Very High Frequency

There are two (2) types of VHF Marine Radios:

1. Hand Held or Portable

. Has its own power source. . Has its own antenna . Transmits 5 watts of output power . Is more easily water-proofed.

2. Base or Fixed Mobile

. Requires an external antenna. . Requires an external 12 Volts DC power source. . Transmits 25 watts of output power . Bigger display and buttons.

MAIN USES OF A VHF RADIO TO A FISHERMAN:

. As a means of communicating with the Coast Guard or other vessels out at sea in the event of a distress situation or of needing assistance. . Used for collision avoidance. . To receive information of any approaching or threatening weather system. . To talk with other fishing vessels to receive or give information on the locality of productive fishing areas. . To communicate with land base VHF radio stations i.e. boat owners, fish buyers etc. . To advise other mariners when detecting floating obstacles out at sea that is dangerous to ships travelling in the area.

PARTS AND FUNCTIONS OF A VHF MARINE RADIO

Antenna

An Antenna is a device (normally made of wire) that collects or transmits a radio signal.

Power Supply

A Power Supply is a device that takes ordinary house A.C. voltage, steps it down to a lower voltage and converts it to D.C. mainly 13.8 volts to power the radio. Generally all Marine Transceivers are powered by 13.8 volts D.C. On most fishing boats, an automobile battery is considered a power supply.

Microphone

A Microphone is the device that you speak into the Marine Transceiver. When you speak into a Microphone on a Marine Radio, your voice goes into the transmitting section of the transceiver where it is converted to Radio Frequency Signals and sent through the Transmitting Antenna to the atmosphere where it is picked up by other VHF radios on the same channel.

Transceiver

A Transceiver is a combination of a receiver and transmitter in one package. All marine radios today are transceivers. They share one common power pack.

Squelch

The Squelch knob on a marine radio is used to cut the inherent noise that is always present on the radio’s receiver in the absence of a signal from radio or radio’s on the same frequency. The proper adjustment for the Squelch control is to counter clockwise until you hear noise and then clockwise until the noise just disappears. In that position the radio will be quiet until someone transmits on that frequency. This is called Squelch Threshold.

Volume

The Volume Control knob is used to regulate the level of the signal being received through the radio speaker. The level of adjustment is purely up to the individual.

Transmitter

A Transmitter is a integral part of a marine transceiver. The Transmitter’s sole purpose is to take the speech from the microphone, convert it to an R.F. Signal and transmit it into the atmosphere, through the Transmitting Antenna, where it is picked up by the Receiving Antenna.

Receiver

The Receiver is the other part of a Transceiver. Its purpose is to receive the signal being transmitted by the Transmitter through the Antenna – amplify it and convert it to the speech that is received through the speaker.

VHF RADIO OPERATING PROCEDURES

1. Press your microphone button for about two seconds before you start to speak. This ensures that the first part of your message will not be missed.

2. Adjust and turn the squelch button on your radio counter clockwise until the squelch noise stop.

3. Never keep a conversation on Channel 16. VHF Marine Radio contains several Channels. Among them is Ch 16, which is used only as a calling Channel and for emergency and distress use. Most marine craft standby on Ch 16 but once contact is established on Ch 16, you must switch to a working Channel e.g. channel 11;12;or 14 Each marine radio is equipped with a Channel switch or button and its purpose is to switch from Ch 16 to other working Channels.

4. Commence transmission by calling the person you wish to talk three times, followed by your own call sign once

a. (e.g. Fishing vessel Big Tuna; Big Tuna; Big Tuna ; This is Dolphin Star;). b. If after calling a second time, there is no answer, wait for about five minutes before calling this same boat again.

5. Speak clearly and distinctly into the microphone held about 2 inches from your mouth. DO NOT SHOUT. 16

6. Release the microphone button after transmission. Remember – Press to talk. Release to listen.

7. If a message was not received in part or in it’s entirely, asked thee other party to "Repeat all after " or "please repeat the entire message". OR ‘Say again’

8. Always ensure that your receiving/transmitting environment is free from interfering noises such as (radio playing, loud talking etc). Messages must be transmitted and received clearly.

9. Always acknowledge all messages received. It is not necessary to use ‘over’ after every transmission.

10. Check your radio from time to time to ensure that the unit was not unintentionally turned off or the volume turned down. It is also a good idea to check to see if your microphone button is stuck (red transmit light stays on). Periodic checks with a base station are highly recommended.

11. Please extend courtesies to other users of the radio and while someone else is transmitting. If you wait your turn you will get through. Do not hog the channel; make your transmissions brief and concise.

12. Be professional in all your transmissions on the radio. This communication system is for your benefit; please keep in mind the purpose it is intended for.

13. Never use profane or obscene language or transmit fraudulent messages on a VHF radio.

DISTRESS CALLING

A mayday call should only be made in dire circumstances when death, serious injury, or the loss of a boat is imminent. Other emergencies, such as loss of engine power, or running aground, may warrant a request for assistance, but not a mayday call.

Information to Include in a Mayday Call

Ordinarily marine radio users are urged to make only brief transmissions. A mayday call is the exception to that rule. Depending on the emergency, it may become impossible for the caller to stay on the radio, so he should give as many details as possible.

Begin the transmission by repeating the word “mayday” three times.

Give the vessel’s name and description: "This is Dolphin Star, a 55 foot fishing vessel with a blue hull, and white cabin."

Tell how many people are on the boat and their condition: "There are six adults aboard, " (If anyone has been injured, include that information as well.)

Give your vessel’s location. A GPS reading is most useful, but if that is not possible, give as accurate a location as possible: "We are in President’s Channel, about a mile south of Disney Point on Waldron Island, drifting northeast." The more details you can provide the better.

Briefly explain the emergency, what is being done to cope with it, and what you need: "We’ve hit a rock and are taking on water. The bilge pump is working, but not keeping up with the incoming water. We request immediate assistance."

RECEIVING MAYDAY

As soon as possible, vessels that acknowledge receipt of a Distress Message should transmit the following information:

a. Name of vessel 18

b. Position of vessel c. The speed at which it is proceeding towards, and the approximate time it will take to reach, the vessel in distress

d. A Pan Pan call, is an emergency call set out on channel 16 when the boat faces a difficult situation but there is no imminent danger. e. An example of a Pan Pan call might be if you have lost engine power and is drifting but not in a direction that will cause loss of life. f. If you hear a Pan Pan call listen and see if you may be able to provide assistance. If not remain silent. g. To make a Pan Pan call follow the same procedure as for a mayday call but substitute "Pan Pan" for mayday. An example might be as follows: "Pan Pan, Pan Pan, Pan Pan, this is Fishing vessel Dolphin Star, Fishing vessel Dolphin Star, Fishing vessel Dolphin Star at x degrees latitude and x degrees longitude, we have lost engine power, we have six persons on board, we are a 55 foot dhoni with a blue hull drifting with no engine power.

Wait a few seconds for a reply and repeat the message. It may be a fine line between a mayday call and a Pan Pan call, so judge whether there is an imminent danger to life first.

Safety Announcement: "SECURITY, SECURITY, SECURITY" . This is the International Safety Signal and is a message about some aspect of navigational safety or a weather warning.

Phonetic Alphabet

A Alfa H Hotel O Oscar V Victor B Bravo I India P Papa W Whiskey C Charlie J Juliett Q Quebec X X-ray 19

D Delta K Kilo R Romeo Y Yankee E Echo L Lima S Sierra Z Zulu F Foxtrot M Mike T Tango G Golf N November U Uniform ECHO SOUNDERS/FISH FINDERS

Fish Finders

Fishing has been a popular pastime for thousands of years? And the same thing challenges all of us - finding fish and getting them to bite. Although a fish finder can show you where fish is located, it can’t make the fish bite.

When you fish with a fish finder you’re giving yourself an advantage over those who fish without one. Using a finder to fish will allow you to know the structure, depth, and temperature of the area of water your fishing. Some models of fish finder will record where you’re fishing so you can use the finder to return there the following day thanks to GPS

To better understand how fish finders work it's good to cover some basics first.

A fish finder sends sound waves through water. At the source, these sound waves are narrow and gradually widen to form a cone. This is what's referred to as a beam. When the beam encounters something "different" (a solid object like a fish or sea bottom), it bounces back to the fish finder's transducer which convert those minute echoes into an image you can interpret on the display. Some of the more advanced fish finders will have more than one beam so you'll get a clearer image of what's happening below the surface of the water as well as a general direction of where the fishes are located(left, right, front, back). A wider cone will give you a wider coverage area and is therefore preferable over a narrow cone for shallower waters.

If fish pass under a fish finder's beam, it typically shows up as an "arch," which is how the unprocessed sonar return from fish usually looks like. With time and experience, you'll be able to generally tell what kind of fish are in the vicinity based on the kind of images you get from a fish finder. For 20 example, slow moving fish will tend to have thicker arches, while very fast swimmers will appear more like a dotted arch.

Some of the more sophisticated fish finders will even have software to take the guesswork out of interpreting sonar readings by displaying a fish icon instead of an arch. It's up to you to decide if this is something you really need. Some fishermen actually prefer the challenge of interpreting sonar returns.

Apart from showing fish arches, a fish finder can help you find fish in other ways. Sometimes, you'll be able to catch more fish by learning to use these other features than by relying solely on your fish finder to spot fish arches.

How Sonar Works On Your Fish Finder

Did you know that the word "sonar" is an abbreviation for "SOund, NAvigation and Ranging"? Sonar was developed as a means of tracking enemy submarines during World War II The Sonar on your finder sends out a beam. This beam is actually a sound wave. The beam goes through the water until it reaches structure including rocks and the bottom of the water you fish. Once the beam hits structure it then travels back to your finder where the fish finder software displays the results of the water you fish.

Commercial fishermen mainly use sonar for finding schools of fish at the surface or mid-water. Included in these results are fish in the radius of the beam, water temperature, depth, and any structures off the bottom such as rocks etc.

Screen Resolution

Much like buying a TV, buying a fish finder will have you considering things like screen resolution and pixels. Screen resolution is basically the number of pixels or dots. The more pixels the finder has the better the quality of picture it will produce. If you’re buying a fish finder for commercial fishing, then a 240 x 240 screen resolution will provide a nice display of the fish. There are much higher resolutions, but once again keep in mind just like a TV the higher the resolution the higher the price of the fish finder.

Power – Wattage 21

The makers of fish finders describe the strength of their finders in watts. The higher the watts the more powerful the unit will be which translates to efficiency and speed. The deeper the water you fish the higher the wattage you need. If you fish close to the shore which is relatively shallow then you can get away with a lower watt finder. It is recommended going with the highest watt fish finder you can afford. You will be thankful you went with the higher watt unit down the road as higher watts translates into more speed and efficiency even if you only fish in shallow water.

Transducer

The transducer could be thought of as the fish finder's "antenna." It converts electric energy from the transmitter to high frequency sound and the sound wave from the transducer travels through the water and bounces back from any object in the water. When the returning echo strikes the transducer, it converts the sound back into electrical energy which is sent to the sonar unit's receiver. The cone angle is the size of the beam sent out by the finder. The transducer is the part of the finder that sends out the sonar or sound beams. To keep this simple the cone angle is how wide the beam the transducer sends out to determine what’s in the water you’re about to fish. The wider the beam the more feedback you’ll get from the finder on structure and fish in the area. The good news about Transducers and cone angles is you can always upgrade in the future to increase the area of the water you see. Most fish finders come with a transducer producing a good cone angle so don’t fret about this for the time being.

Screens You’ll have your choice of black and white or color fish finder screens. Both work well, however the color will help you identify objects a little better, but once again like TV’s color is more expensive than black and white. Color and black and white is really a personal preference. A back lit display is critical if you fish at night. This feature will light up the display for viewing.

Readings Many if not most fish finders now offer water temperature readings. This is the water temperature at the surface. If you fish a lot you know that water temperature plays a key part in locating the fish. 22

Speed If you like to fish by trolling then having your fish finder’s display give you the speed is a real nice feature to have. This will allow you to adjust the speed of the boat to match the speed the fish are hitting at.

GLOBAL POSITIONING SYSTEM

WHAT IS GPS

The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense. GPS was originally intended for military applications, but in the 1980s, the US government made the system available for civilian use all over the world. GPS works in any weather conditions, anywhere in the world, 24 hours a day. There are no subscription fees or setup charges to use GPS.

How a GPS Works

GPS satellites circle the earth twice a day in a very precise orbit and transmit signal information to earth. GPS receivers take this information and use triangulation to calculate the user's exact location. Essentially, the GPS receiver compares the time a signal was transmitted by a satellite with the time it was received. The time difference tells the GPS receiver how far away the satellite is. Now, with distance measurements from a few more satellites, the receiver can determine the user's position and display it on the unit's screen.

A GPS receiver must be locked on to the signal of at least three satellites to calculate a 2D position (latitude and longitude) and track movement. With four or more satellites in view, the receiver can determine the user's 3D position (latitude, longitude and altitude). Once the user's position has been determined, the GPS unit can calculate other information, such as speed, bearing, track, trip distance, distance to destination, sunrise and sunset, time and more. 23

How accurate is GPS?

Today's GPS receivers are more accurate, thanks to their parallel multi- channel design and new land base infrastructure to enable pinpoint accuracy. Most marine GPS receivers however, are accurate to within 15 meters on average.

The GPS satellite system

The 24 satellites that make up the GPS space segment are orbiting the earth about 12,000 miles above us. They are constantly moving, making two complete orbits in less than 24 hours. These satellites are travelling at speeds of roughly 7,000 miles an hour.

GPS satellites are powered by solar energy. They have backup batteries onboard to keep them running in the event of a solar eclipse, when there's no solar power. Small rocket boosters on each satellite keep them flying in the correct path.

Here are some other interesting facts about the GPS satellites;

 The first GPS satellite was launched in 1978.  A full constellation of 24 satellites was achieved in 1994.  Each satellite is built to last about 10 years. Replacements are constantly being built and launched into orbit.  A GPS satellite weighs approximately 2,000 pounds and is about 17 feet across with the solar panels extended.  Transmitter power is only 50 watts or less.

WAYPOINT 24

A waypoint is a reference point or set of coordinates that precisely identify a location. A waypoint includes latitude and longitude data. Most GPS receivers allow the user to easily set, store, and reference multiple waypoints. Your GPS will allow you to save a large number of waypoints, any of which you can rename to something that you will recognize, rather than using the default name. In practical use, GPS device displays can point to, or give specific directions to pre-set waypoints. Also, specific and detailed routes may be established with multiple waypoints. Waypoints may be set while a GPS user is physically positioned at the desired waypoint. Waypoints may also be set by manually entering known coordinates into the GPS receiver.

Most fishermen will store the following locations as waypoints in their GPS:

1. Home port. 2. Landing jetties etc. 3. Good fishing grounds. 4. Good anchoring location. 5. Neighboring countries. 6. Various coastal cities / villages / atoll / islands in your own country. 7. Navigational or marker buoys. 8. Dangerous reefs or wrecks.

ROUTE In GPS navigation, a "route" is usually defined as a series of two or more waypoints. To follow such a route, the GPS user navigates to the nearest waypoint, then to the next one in turn until the destination is reached. Most receivers have the ability to compute a great circle route towards a waypoint, enabling them to find the shortest route even over long distances.

USES OF A MARINE GPS

A. To mark productive fishing ground so that you can return to the exact location another day. B. To enable you to accurately navigate to the fishing ground and travel back to your home port after fishing activities. C. To enable rescuers to accurately come to your position in the event that you are in distress and requiring assistance. 25

D. To enable you to travel accurately to another vessel that may be in need of assistance. E. To mark the position of the existence of a reef or wreck that may cause a danger to mariners. F. To inform you of your present distance from land while fishing out at sea. G. To provide GPS coordinated to other fishing vessels on the existence of good fishing location. H. To be used to provide anchor alarm in the event that you are dragging anchor. I. After leaving the fishing ground and you are travelling back to your home port, the GPS will enable you to provide information to your fish buyer or vessel owner of the estimated time of arrival ETA. J. To give you information of the distance to the nearest port in the event of an emergency on board your fishing vessel or of an impending threatening weather system. K. To provide time of day to fishermen out at sea. L. To give the speed of your vessel.

TUNA BEHAVIOUR

Introduction

Tunas are among the largest, most specialized and commercially important of all fishes. Belonging to the genus Thunnus of the family Scombridae, they are found in temperature and tropical oceans around the world and account for a major proportion of the world fishery products. Biologically, tuna species have complex life history. They have streamlined bodies and vary extensively in size, color and fin length. Tunas are unique among fishes because they possess body temperature several degrees higher than the ambient waters and have high metabolic rates that enable them to show extraordinary growth patterns. Tunas are fast swimmer and capable of traveling more than 48 km per hour. They are migratory and have few predators.

Tunas are in great demand throughout the world market due to their excellent meat quality. The tuna industry has been a successful program in the past. However, problems on the fishing stock status have occurred due to the recently increased fishing intensity.

There is an urgency to conserve the tuna resources due to the awareness of decreasing tuna stocks. Although the data for the principal market tuna species have been accumulated for a long time, uncertainties exist in the basic distribution of these species. There have been few studies on large- scale distribution of tuna species. Information on where and when tunas occur can be critical for resource management and practical for fishery vessels. Despite the abundant literatures on the tuna resources in the Indian Ocean, there appears to have a lack on the study of distribution pattern of 27 these tunas. To better conserve and maintain a sustainable yield of these species, there is a need to understand large-scale patterns of tuna stocks in space and time.

The Indian Ocean, having about 20% of the global tuna production, is the second largest proportion of principal tuna market in the world. Japan, Taiwan and Korea are the major fishing countries in the Indian Ocean. In recent years, tuna fisheries are growing in this ocean, partly due to the catching of small tunas by the non-traditional tuna catching countries, such as French, Ivory Coast, Spain, and etc (FAO, 1997).

FACTORS WHICH MAY AFFECT FEEDING BEHAVIOUR IN TUNA SPECIES

1. Water temperature 2. Currents. 3. Water clarity. 4. Spawning. 5. Stomach fullness. 6. Prey quantity. 7. Prey quality. 8. Predation risk. 9. School formation.

SKIPJACK TUNA

PHYSICAL CHARACTERISTICS

Skipjack Tuna are dark blue or purple on the back and silvery on their lower sides and belly. They have three to five prominent, dark longitudinal bands on their lower sides. Pectoral fins short, with 26 or 27 rays. Body naked except for anterior corselet and lateral line. These tuna have fine, slender teeth. Swim bladder absent. They have a total of 53-63 gill rakers on the first gill arch.

The fish is a nonstop traveler and feeder. They move in schools following the ocean currents and feed on both zooplankton and small fish. Their diet 28 seems to be dictated by whatever bait is available in a given area. Their main prey are small oceanic fish. When feeding on plankton skipjack tuna can be an utterly frustrating as they boil across the surface but refuse to take trolled or cast lures. Striped tuna schools are sometimes vast but more frequently they are found feeding in small pods. Striped tuna grows to about 10kg and are regularly caught at 6 to 8 kg although the average size is 2 to 3 kg. Their average swimming speed is about 10 -12 knots although they are capable of 20 to 30 knots in bursts and they burn a lot of energy maintaining that speed; So much energy in fact they have a body temperature higher than the surrounding seawater. This is rare in fish which are mostly cold blooded. The non stop, high speed swimming is what makes tuna a ball of muscle and what gives them such huge strength when they end up on the end of a hook.

DISTRIBUTION

Found mainly in tropical and warm-temperate seas.

HABITAT

Aggregations of this species tend to be associated with convergences, boundaries between cold and warm water masses. Depth distribution ranges from the surface to about 853 ft (260 m) during the day.

BEHAVIOR

Skipjack show a strong tendency to school in surface waters. Schools are associated with birds, drifting objects, sharks, whales, and other tuna species.

FEEDING ECOLOGY AND DIET

The depth range of skipjack tuna can be from surface waters to 260m during the day, but at night it is much shallower. Skipjack tuna are a schooling fish having a general tendency to school by size. Skipjack tunas are actively feeding during daytime from morning to sunset, but they do not feed at night. 29

Skipjack are opportunistic feeders preying on any forage available. Feeding activity peaks in early morning and late afternoon. They are not known to feed at nights.

REPRODUCTIVE BIOLOGY

Skipjack spawn in batches throughout the year in equatorial waters. The spawning season becomes shorter as distance from the equator increases. The number of eggs per season in females 16–24 in (41–87 cm) fork length ranges from 80,000 to two million.

SIGNIFICANCE TO HUMANS

Skipjack makes up approximately 40% of the world's total tuna catch and have come to replace yellowfin as the dominant commercial species of tuna. Catches of skipjack were reported to FAO by 94 countries for 1991–2000, 1,584– 2,191 thousand tons (1,437–1,988 thousand metric tons) per year. The highest catches reported for 2000 were by Japan, 376 thousand tons (341 thousand metric tons), and Indonesia, 298 thousand tons (270 thousand metric tons). Skipjack are taken at the surface, mostly with purse seines and pole-and-line gear, occasionally with long lines. They are marketed fresh, frozen, and canned (as light-meat tuna). They are also a game fish, the all-tackle gamefish record is a 45-lb (20.5-kg) fish caught on Flathead Bank, Baja California.

YELLOW FIN TUNAS

Yellowfin tuna adults are distinguished by having a moderately long pectoral fin that is one third to one quarter the body fork length. In juveniles there are about 20 broken pale lines crossing the lower sides. In large fish, the second dorsal and anal fins may be exceedingly elongated and bright yellow. Yellowfin tuna less than 75cm fork length (10kg whole weight) may be difficult to distinguish from small bigeye tuna.

A beautiful and colourful tuna. Blue to steel black above, silver to silvery gold on the flanks, silvery white below. In fresh fish a band of bright gold or iridescent blue (sometimes both) runs along the upper flank, separating the dark back from the lighter belly area. 30

The stomach area sometimes carries oval, colourless patches and vague broken vertical bars of white. These are more obvious in juveniles.

The yellowfins fins are bright yellow. The finlets, in particular are canary yellow with black margins.

Yellowfin is a very good eating fish. It is extremely good as sashimi (raw fish).

Yellowfin Tuna are found close inshore, in clean warm currents, but are more common on the Continental Shelf areas. They prefer clean water with water temperatures of 17-27ºC. They rarely venture into dirty, discoloured areas.

Yellowfin feed both on the surface, and well down in the water column.

Small yellowfin (2-12kg) will take trolled and cast lures, small live baits and sometimes cut flesh strips. Larger yellowfin take small and medium live baits, up to and including live frigate mackerel, bonito and striped tuna weighing as much as 5kg plus.

Yellowfin are extremely powerful and demand the best in tackle and gaffs!

NEW DISCOVERY IN YELLOWFIN TUNA BEHAVIOR

The joint effort of two research projects on tuna in Seychelles, FADIO, a European project on the fish behavior around floating objects, involving the Seychelles Fishing Authority (SFA), Institute de Recherché pour le Developpement (IRD), France and other European partners, and RTTP-IO, the tuna tagging project of the IOTC, has recently led to a new discovery in the ability of tuna to dive deep. During a FADIO research cruise in October 2004, a yellowfin tuna weighing approximately 50kg was tagged onboard the Indian Ocean Explorer. The fish was captured using a surface trolling lure in the Amirantes archipelago. A tag was inserted in the body cavity using surgery procedure. This tag records swimming depth, sea temperature, body temperature and light level every 30 seconds, thus providing estimates of the position of the fish. The fish was also marked with an external IOTC 14cm plastic dart tag which assists the IOTC in determining tuna stocks, and subsequently released. The fish was recaptured in January 2005 by a tuna purse seiner approximately 250 miles west of the Amirantes archipelago, after 98 days at 31 liberty. However, the tag was only returned to researchers in January 2006, after the fish was unloaded and processed in Mombassa, Kenya. The fish spent most of its time in the surface mixed layer, which is an approximately 50m deep ocean layer where the sea temperature does not vary much. However, on three separate days within a period of one month, the yellowfin tuna performed three deep dives reaching the depths of 578m, 982m and 1,160 m. The deepest dive lasted about 2 hours, and the fish experienced a huge difference in temperature, ranging from 29oC at the surface to 6oC at 1160 m. Its body temperature dropped from 26oC to 13oC, which implies a strong physiological change. The reasons for these deep dives are still not well understood - could they have been for foraging purposes, predator avoidance, anti-parasitic behavior, or association behavior with big animals able to dive deep? The rarity of these deep dives, however, suggests that this is not typical foraging behavior; on the other hand, the quite slow rate of descent and the prolonged time at depth does not suggest predator avoidance. Had this been the case it would most probably have been indicated by "bounce dives" at higher speeds. One could speculate that this individual could have dived to such deep and cold waters to get rid of parasites but almost no information currently exists on the effects of parasites on the behavior of tuna. It is also known that tuna sometimes associate with large animals such as sperm whales, whales, and whale sharks that are able to dive to great depths and it is possible that exceptionally, this individual accompanied such a large animal into the depths. More tagging results will certainly improve our understanding of why yellowfin tuna sometimes dive deep. One thing that is certain, and proven by the returned tag, is that this species is a surface-oriented species and preferentially occupies shallow waters (within the first 50 metres below the surface), unlike bigeye tuna that usually frequent deeper waters.

Seabirds

Seabirds depend on the marine environment. Although they nest on land, they spend almost their whole lives at sea. They have become highly specialized and adapted to life on the sea. They can fly and swim for hours or days, protected from the cold by thick down under water- repellant feathers. Most seabirds rest and sleep on the rolling waves, while others roost on land for a few hours a day. But all seabirds must return to land to lay eggs and raise their young When seabirds gather on remote islands and rocky outcroppings, they form what we call a colony.

We are able to study seabirds both on the open sea and on their colonies

Seabirds and fisheries

Seabirds have had a long association with both fisheries and sailors, and both have drawn benefits and disadvantages from the relationship.

Seabirds are not only inspiring to watch as they gracefully glide on the air currents above the ocean surface, but they are a valuable asset to local fishermen who depend on them to locate the large yellow-fin tuna and other fish schools. Large gatherings of mixed seabird species flock together to feed on smaller fish pursued by the tuna.

Commercial fishermen have used the distinctive feeding patterns of seabirds as clues to the identity of type of fish that is feeding below the surface, thus they can make adjustments to their gears, bait and approach to the fish school.

When seabirds are active low over the water, they usually are feeding on skipjack tuna; If the flocks alternate between low and high altitudes, they are probably following yellow fin tunas; As periods between surfacing fish schools become longer, the flock disperses and sooty terns fly higher and higher to act as the eyes of the flock. From distance up to eight kilometers, fishermen recognize the flash of white when sooty bank en masse from horizontal flight to make swooping dives on surfacing fish. 33

Fishermen have also traditionally used seabirds as indicators of both fish schools, underwater banks that might indicate fish stocks, and of potential landfall. In fact, the known association of seabirds with land was instrumental in allowing the Polynesians to locate tiny landmasses in the Pacific. Seabirds have provided food for fishermen away from home, as well as bait. Famously, tethered cormorants have been used to catch fish directly. Indirectly, fisheries have also benefited from guano from colonies of seabirds acting as fertilizer for the surrounding seas.

Negative effects on fisheries are mostly restricted to raiding by birds on aquaculture, although long-lining fisheries also have to deal with bait stealing. There have been claims of prey depletion by seabirds of fishery stocks, and while there is some evidence of this, the effects of seabirds are considered smaller than that of marine mammals and predatory fish (like tuna).

Some seabird species have benefited from fisheries, particularly from discarded fish and offal. These discards compose 30% of the food of seabirds in the North Sea, for example, and compose up to 70% of the total food of some seabird populations.

All most people ever know about seabirds comes from watching them at their breeding colonies. Scientists are no different; observations at the colony form the foundation of what we know about seabird biology. Colony work gives answers to questions such as; How many seabirds attempt breeding each year? How many chicks do parents produce? And how hard did the parents have to work to raise those chicks?

But without understanding what seabirds do at sea, we would never completely understand their biology. Without adequate food, seabirds cannot raise chicks and they might not even be able to sustain their own life... and everything seabirds eat comes from the sea.

Information on where and when seabirds concentrate at sea, and (as fishermen have always known) how those concentrations are related to what is going on under the ocean’s surface. Lately we’ve begun using oceanographic sampling gear and satellite images of the ocean’s surface to link seabird concentrations to factors like the temperature and salinity of the 34 seawater. We also identify the location of ocean features called ‘fronts’- where two water masses collide.

COLONIES

Life on a seabird colony is crowded! At the beginning of each summer, hundreds to thousands of seabirds pack together to nest on remote islands and coastal bluffs. They do this because there is safety in numbers and the whole colony is alive with breeding activity, which encourages the birds to nest.

Each seabird species has its favorite habitat on the colony. Some prefer beach rubble and boulders or the cracks in a cliff face. Others nest side by side on rocky ledges. Some seabirds dig a dirt burrow into the soft soil at a cliff edge. Still others nest on the flat ground at the top of the colony. Many seabirds return to the exact spot that it nested on last year

Population Trends

Seabird colony populations change all the time as adults die of old age or from un-natural sources of mortality (like oil pollution, or drowning in gill- nets), young birds mature and join the colony to begin breeding, or because birds change their breeding sites. Because seabirds typically gather in large, multi-species colonies, it is relatively easy to count their numbers during the summer breeding season. At small colonies, we might count all the birds present at one time. At large colonies with hundreds of thousands or millions of birds, it is impossible to count all the birds, so we typically count numbers in smaller sub-areas and use these data to estimate population trends. Censusing is vital to monitoring the status and health of seabird populations, and provides a key source of information for researchers and managers.

BREEDING BIOLOGY

One way that scientists try to understand how seabirds are affected by changes in the marine environment is by studying their breeding biology. Seabirds spend most of their lives flying across the ocean, resting on the ocean, or swimming beneath the surface. But they must return to land, usually islands, to lay eggs and raise chicks during the annual breeding season. These islands are often very small, but they may support hundreds of thousands of birds that have come from hundreds or even thousands of miles away to nest there. These islands are often very remote and inaccessible, however, if they are accessible, having large numbers of birds in a small area makes it easier for biologists to study them.

By observing the birds on land when they are breeding, we can get an idea of how healthy that group of birds is at that point in time. This also tells us a lot about what is going on in the ocean. If there is a lot of food (mostly forage fish) around the colony, then the adult birds will be healthy, many of these young will fledge from the colony. No single observation paints the whole picture so we collect a lot of detailed information to determine how well the birds and their marine environment are doing. Some examples of the information we collect are: how many chicks are raised by each pair of birds, how fast the chicks grow, adult and chick diets, adult time budgets, adult stress levels, survival rates, and genetics.

DIETS

Knowing what birds eat is an important part of understanding their behavior and survival. Seabirds obtain almost all their food from the sea either by themselves or in large feeding flocks. Their diet consist primarily small fish and squid (less than 6 inches long) for larger birds, tiny shrimp-like zooplankton for small ones. Some species feed on the ocean surface, others by diving; some feed near shore (within 5 kilometers), others far offshore (30 kilometers or more). Since some foods may be better than the rest, we want to know what kinds of food seabird adults and chicks are eating.

Most seabirds prefer prey that are concentrated in dense schools (which are easiest to find), and that are oily (because they are energy-rich and repay the effort of catching them). If energy-rich fish are not available, birds will increase their intake of low-fat fish. A few birds spice their diet with non-fish foods: gulls may take other species' young, jaegers take mice and sometimes other birds' food, parakeet auklets eat jellyfish. A few species eat garbage if it's available, or try to grab the bait from fishermen's hooks. Birds that eat zooplankton also depend on certain species.

Birds do not search for food at random -- they look for places where they can find a lot of it predictably. They flock to fish schools. Currents may cause prey to converge near headlands or between islands. Food also is found at upwellings, where water is forced from the nutrient-rich ocean floor to the surface at undersea ridges and the shelf edge.

Seabird parents capture prey at sea and bring it back to their chicks. We study chick diets according to how each species feeds its young. Puffins, pigeon guillemots, common murres, and murrelets carry whole fish (or sometimes squid), in their bills to their chicks. We crouch in hidden blinds and watch the adult birds as they fly back to the colony to feed their chicks. With binoculars we can identify the fish they carry and get an estimate of its length in relation to the length of the bird’s bill. Kittiwakes and gulls feed their chicks differently. They swallow whole fish for their chicks at sea. When they return to the colony, they regurgitate this food for their chicks. We collect some of these regurgitations and analyze their contents to learn about their chick diets.

Fisheries also have negative effects on seabirds, and these effects, particularly on the long-lived and slow-breeding albatrosses, are a source of increasing concern to conservationists. The bycatch of seabirds entangled in nets or hooked on fishing lines has had a big impact on seabird numbers; for example, an estimated 100,000 albatrosses are hooked and drown each year on tuna lines set out by long-line fisheries. Overall, many hundreds of thousands of birds are trapped and killed each year, a source of concern for some of the rarest species (for example, only 1,000 Short-tailed Albatrosses are known to still exist). Seabirds are also thought to suffer when overfishing occur.

SEA SURFACE TEMPERATURE SST

The sea covers two thirds of the earth's surface. To a large extent, man is dependent on it for food species which include fish, shellfish, marine mammals, turtles, aquatic plants and algae. To exploit these resources more effectively, fishermen must catch the most fish possible while, at the same time, minimizing fuel costs and reducing the time spent at sea in their fishing operations. Time is money. With daily access to accurate up-to-date sea surface temperature data, a fisherman can increase his chances of locating fish quickly. It's a small investment in a new piece of equipment that will pay for itself over and over by reducing the time spent at sea to locate fish.

Fish populations are commonly found in locations where surface temperatures change. A temperature change indicates a point where currents and upwellings meet. Sometimes during the summer, water from the ocean floor rises quickly from the bottom and can cool water temperatures 3-5 degrees in one day.

Upwelling brings with it nutrients which are food for the baitfish which in turn attract larger species.

Remote observations of the sea surface can provide a significant part of the information needed to assess and improve the potential yield of the fishing grounds. In the past, remote sensing was used mainly to assist in the efficient harvesting of natural resources. Today it is being used for resource management, conservation and exploitation. On any day of the year, there is plenty of algae floating on the ocean surface. These plants are food for small fish. The small fish are food for medium size fish. Finally, the medium fish are food for the big boys (Tuna, marlin, sailfish etc). So, if you think about it, generally speaking, wherever there's a lot of seaweed at the surface, you will

38 probably find some sort of big fish down below. The tough part is finding these seaweed lines. When you see huge temperature differences in an image, there are usually surface currents pushing toward each other in an area we call a convergence zone. The surface water, and everything in it, pushes together. When two water masses push towards one another, it's kind of like two conveyor belts facing each other. But seaweed and algae float so they begin to pile up at the surface in large lines. The bottom line: Temperature fronts generally equal some fish. The concentration of chlorophyll pigments is often considered as an index of biological productivity and, in an oceanic environment, it can be related to fish production. Chlorophyll concentrations above 0.2 mg/cu.m indicate the presence of sufficient planktonic life to sustain a viable commercial fishery . Chlorophyll pigments have a specific and distinctive spectral signature since they absorb blue (and red) light and reflect strongly the green, thus affecting ocean colour. Multispectral observations from airborne or spaceborne sensors, therefore, allow the deduction of phytoplankton concentration .

Satellite oceanographic features such as ocean colour, sea surface temperature, chlorophyll-a-concentrations can be successfully mapped in near real-time. This capability coupled with the knowledge of oceanographic conditions affecting fishery population and historical catch data can lead towards the forecasting of fish populations and their movements and thus positively affect the capacity to harvest the fishery resources effectively and on a sustainable basis.

Variations in environmental conditions affect the recruitment, distribution, abundance and availability of fishery resources. It is not possible to measure remotely the entire range of information needed to assess changes in the marine environment. Knowledge of particular conditions and processes affecting fish populations, however, may often be deduced using measurements made by remote sensors, e.g., concentration of dissolved and suspended matter, variations in primary production levels, distribution of surface isotherms, location of frontal boundaries, regions of upwelling, currents and water circulation patterns. The parameters providing information on these environmental factors may allow a forecast of fish distribution or more generally the definition of marine fish habitats. These are often easier to sense remotely than the presence of fish. 39

Remote sensing techniques can be utilized directly, indirectly or as general aids in the detection and assessment of fishery resources.

Measuring of Sea Surface Te m p e r a t u r e

Maps of sea surface temperature (SST) are directly relevant to fisheries because of the temperature preferences of individual fish species, and maps of SST reflect currents and zones of upwelling or downwelling water. Operational ocean surface temperature maps derived from satellites are routinely used not only by commercial fishing operations but also by sports fisherman to plan outings.

Because temperature and currents are related, SST maps help refine understanding of currents and circulation described above. An example is the identification of ocean circulation features such as cold/warm-core rings. In a warm-core ring, warm water species of fish such as shark and swordfish congregate; they find more food along the rotating perimeter of a warm eddy. These data also indirectly aid fishermen and fisheries managers because SST is directly related to weather and climate.

SST can be obtained directly from satellite remote sensing. The longwave (thermal infrared) radiation emitted by an object is mathematically related to the temperature of that object. MODIS includes several bands sensitive to the ther-mal infrared, allowing precise, daily measurement of SST over the world’s oceans.

A piece of onboard equipment which commercial fishermen use, and which can tell you the surface water temperature where you are travelling is a ‘water temperature gauge’ where the sensor is directly below the boat and the display unit is in you cabin area.

WHY IS SEA SURFACE TEMPERATURE SO IMPORTANT TO OFFSHORE FISHING?

If you are an experienced offshore fisherman, you already know the answer to this question. If not, here's a brief explanation - It's a big ocean out there and offshore fisherman, whether recreational or professional, must choose a particular target area for a particular species on a particular day. Good fisherman use all of the tools available to them to put together a successful game plan. The more tools available and the more experience a fisherman 40 has in using those tools the more successful the fisherman will be in finding fish. Water temperature information is one tool that can be critical in evaluating potential destinations. Professional and serious commercial fishermen won't leave the dock without having an idea of where to find good water.

Fish follow bait and comfortable water temperatures. For various reasons bait congregate at certain "structure". Structure can be the topography of the ocean bottom, a floating weed line, debris or along temperature boundaries which can indicate different water masses that don't easily mix. Each of these structure can cause bait to accumulate and shortly thereafter predators will arrive, whether it be marlin, tuna, dolphin, wahoo, or sharks. By locating the potential for concentrations of bait and the comfortable water temperature range for your target species, you can greatly increase the odds of finding the fish you are after. If you can find a place in the ocean where the above conditions are met, you have the ingredients for a fantastic commercial fishing trip!

SOME COMMON FISH SPECIES AND THE OPTIMUM TEMPERATURE WHERE THEY COULD BE CAUGHT

SPECIES OPTIMUM TEMPERATURE WHERE FISH IS FOUND Skipjack Tuna 64-72 Yellowfin Tuna 72-82 Swordfish 60-70 Dolphin (fish) 72-78 King Mackerel 68-76 Sailfish 72-82 Albacore 62-65 Blue Marlin 74-82 Barracuda 72-80 Bigeye Tuna 62-74 Blackfin Tuna 70-74

STRATEGIES FOR FISHING FAST MOVING SURFACE SCHOOLS

You've probably heard this joke: "Why are some fish smarter than others?" The answer is, "Because they hang out in schools."

But schooling is no joke - for some fish, it really is the smart way to survive.

A school of fish can have just a small number of members - or it can have more than a million! The fish in a school are usually the same species (kind). Some species of fish live in a school almost all their lives. Others form schools only at certain times, like right after they've hatched.

A school can be made up of fish that just hang around together. But many schools are very organized. The fish swim barely a fin's length away from each other. And each fish in the group moves at the same speed and in the same direction as the others. In the blink of an eye, a whole school will swim right, left, up, down, or even make a U-turn - all at the same time. It's kind of like a fishy marching band!

TRICKS OF THE TRADE

How do the fish move like that without swimming right smack into each other? One way they do it is by being copycats. Each fish watches its neighbors and copies every move they make - quickly! Meanwhile, the neighbors are copying their neighbors, and so on. So the whole school makes the same moves, and there aren't any crashes.

Besides using their eyes to help them school, fish also use something called lateral lines. These are sensitive places along the fish's sides where they can feel their neighbors' movements in the water. Then the fish make the same movements.

Schooling fish may also tell each other which way to move. Of course, a fish can't shout, "Turn left!" But some kinds of fish can talk to each other with clicks or other signals. 42

So why do fish swim in schools? Lots of reasons. The main one is to stay safer from enemies. When there are lots of fish swimming together in a school, it's hard for a predator to pick out a single fish to attack, so it may not try.

But some predators will swim right through a school anyway and catch some fish. The more fish there are in a school, though, the better the chances are that "the other guy" will get caught. So usually a fish is still safer in a school than swimming alone.

BREAK IT UP

When a school of fish runs into an enemy, it sometimes separates into two groups that flow right around the predator. Then the groups join together again as soon as they've passed the enemy.

Why else do fish school? Another reason is that it's often easier to find food by schooling. The more fish there are looking for food, the more likely it is that they'll find some. Hundreds of pairs of eyes can spot food far better than one pair could.

THE BUDDY SYSTEM

Sometimes a school of fish will find food by hanging around with a "buddy."

There are still other reasons that fish school. They may school to find mates. Or some kinds may gather together to migrate (travel from one place to another).

TROLLING IN HIGH MOVING SURFACE SCHOOLS

Seeing a mass of fish feeding on the surface always raises the excitement level for any fisherman, as this often means the fish are hungry and should be easy to catch.

In some cases a shiny hook or a hook with a piece of rag tied to it will catch fish after fish, while on another day you can troll around and around - even directly through the school - with zero results. This can be utterly frustrating, but there are tactics that can change the results dramatically. 43

Every school of feeding fish has a different make-up that depends on a wide variety of elements. These can include the species of baitfish being hunted, which can be anything from clouds of minute krill (a shrimp-like animal) through to large kahawai. And the type of predators feeding on them can range from small mackerel and kahawai through to large gamefish such as kingfish, sharks and marlin. In large work-ups you can get the entire food chain taking place, which is quite spectacular.

What the predators are feeding on has a direct relationship to the speed at which the schools move and how long they stay on the surface.

The first decision an angler has to make when approaching a work-up is what lure to use. Observation of how the predators are feeding and what they are feeding on will influence this decision. Probably the most frustrating trolling is when the fish have such an abundance of easy prey that your offerings are totally ignored. This is most often the case when the predators are feeding on krill or very small baitfish.

The best solution is to use very small lures, such as saltwater flies, very small trolling squids, or tiny silver spoons in sizes no larger than 2-5cm.The top colours are pink or white.

The action of these lures is not so vital; it is far more important to get ahead of the feeding fish so your lure gets in front of them.

The larger the baitfish, the bigger the lure and the more action it will require. Diving minnows are ideal when predators are eating larger prey items.

When working a school that is popping up and down very quickly, it can be hard to get your lure among the action. It may be necessary to pull the lures in and chase the schools at speed. Try and use any birds to anticipate where the fish are moving. Remember, they have an aerial view of the action. After a while you get used to the birds' body language and can tell when a work- up is about to erupt.

Once you have sorted out the lure pattern, the next decision is how far back you should run your lure or lures. In most cases 10-60 metres will be a good distance. It is quite amazing how close to the props fish will come to take a lure. If possible, set three or four lures at varying distances. 44

The speed that lures are trolled can best be judged by how the lure is performing. Small lures need less speed to be effective - around 1-3 knots - while large diving minnows and game lures will work between 5 and 10 knots. Try letting out a little more line and slowing down a little if the lure is breaking out of the water instead of swimming.

Once lures are swimming well and the speed is sorted out, the next trick is to get the lures in a position where they can be eaten. At times this can be fairly obvious because of the surface action. The best spot to be is ahead of the school and travelling in the same direction. If this is not possible, swinging your boat so that lures pass across the feeding fish is the next best option. The worst course of action is to drive directly through the school or so you split them in any way. This can drive them down and they may not resurface.

Many times you just can't get to the work-up in time. Don't be put off. The melee may still be going on below the surface. This is where a good sounder and using a couple of tactics to get lures a little deeper will bring strikes a- plenty.

If you have the benefit of a good fish-finder, do a few figure-eight circuits around where the work-up was and you may pick up the bait ball being chased by predators. While doing this, try deploying your lures using one of any number of devices for taking lures deeper. This could be a simple trolling lead or a more elaborate downrigger. Using this technique will often result in solid strikes long after the surface action has died off. It is also a very good technique to use when prospecting or working around structure when there are no visible signs of action.

SEAMANSHIP

The Chain of Command

The Captain is ultimately responsible for the safety of the crew on board his vessel; therefore, he must also carry the ultimate authority. Imagine if every one of the crew did whatever they felt like...one might steer north, one might steer south, one might decide to set all sails, while another might set no sails at all. To avoid such chaos, the Captain is in charge and “the Captain is always right.”

An important part of planning for your fishing trip is looking at what happens on land if things go wrong for you on the boat:

 Make sure someone on land knows where you are heading, how long you are away at sea, and when you are due back.  Set up a regular communication/contact schedule (cellphone/vessel radio) with someone on land or maritime radio.  Have a plan in place for the person on land to follow if you miss a scheduled contact or are at sea longer than expected.  Remember: it is best that someone knows your intended plan (even if this changes) rather than no-one notices you are missing.

Before leaving port, your vessel must be ready and capable to travel:

 The vessel must be sea worthy. The vessel must be watertight and equipment must be secured. Vessel stability is improved if fuel and water tanks are full, and weights are kept low.  All fuel containers and other supplies must be safely stored and secured.  The vessel must be safely ballasted.  Consideration must be given to current and forecast weather conditions.

SAFETY AND SERVIVAL TIPS

Operator’s Responsibilities

. Make sure the boat is in top operating condition and that there is no tripping hazards. The boat should be free of fire hazards and have clean bilges. . Safety equipment required by law are on board, maintained in good condition, and you know how to properly use these devices. . File a float plan with a relative or friend. . Have a complete knowledge of the operation and handling characteristics of your boat. . Know your position and know where you’re going. . Maintain a safe speed at all times to avoid collision. . Keep an eye out for changing weather conditions, and act accordingly. . Know and practice the Rule and the Roads (Navigation Rules). . Maintain a clear, unobstructed view forward at all times. “ Scan” the water back and forth; Most boating collisions are caused by inattention.

OVERLOADING

Never overload your boat with fish beyond its safety carrying capacity. If you do not have a fish hold, always balance the load so that the boat maintains proper trim. Here are some things to remember when loading a boat:

. Distribute the load evenly fore and aft and from side to side. . Keep the load low. . Fasten gear to prevent shifting.

Anchoring Anchoring is done for two principal reasons: first, to stop for fishing or overnight stay, and secondly, to keep you from running around in bad weather or as a result of engine failure. Anchoring can be a simple task if you follow these guidelines:

. Make sure you have the proper type of anchor. 47

. A three to six foot length of galvanized chain should be attached to the anchor. The chain will stand up to the abrasion of sand, rock or mud on the bottom much better than a fiber line. . A suitable length of nylon anchor line should be attached to the end of the chain (this combination is called the “Rode”). The nylon will stretch under heavy strain cushioning the impact of the wave or wind on the boat and the anchor. . Select an area that offers a shelter from maximum shelter from wind, current and boat traffic. . Determine water depth and type of bottom (preferably sand or mud). . Calculate amount of anchor line you will need. General rule: 5-7 times as much anchor line as the depth of water plus the distance from the water to where the anchor will attach to the bow. For example, if the water depth is 8 feet and it is 2 feet from the top of the water to your bow cleat, you would multiply 10 feet by 5 to 7 to get the amount of anchor line to put out. . Secure the anchor line to the bow cleat at the point you want it to stop. . Bring the vessel into the wind or current. . When you get to the spot you want to anchor, place the engine in neutral. . When the boat comes to a stop, slowly lower the anchor. Do not throw the anchor over, as it will tend to foul the anchor. . When all anchor line has been set out, back down on the anchor with engine in idle reverse help set the anchor. . When anchor is firmly set, use reference points (landmarks) in relation to the boat to make sure you are not drifting. Check these points frequently.

Do not anchor by the stern!

Anchoring a small boat has caused many to capsize and sink. The transom is usually squared off and has less freeboard than the bow. In a current, the force of the water can pull the stern under. The boat is also vulnerable to swamping by wave action. The weight of a motor, fuel tank, or other gear in stern increases the tank.

Fuel Management

Practice the “One-third Rule “ by using:

. One-third of the fuel going out . One-third to get back . One-third in reserve.

Weather You should never leave for fishing without first checking the local weather forecast. You can get the weather information from the TV, radio, local, newspaper or the internet.

At certain times of the year weather can change rapidly and you should continually keep a “weather eye” out.

What to do in severe weather . Reduce speed, but keep enough power to maintain headway. . Put on your PFDs . Turn on running lights . Head for nearest shore that is safe to approach, if possible . Head bow of boat into the waves at about a 45-degree angle. . Keep bilge free from water. . If your engine fails, trial a sea anchor on a line from the bow to keep the boat headed into the waves. A bucket will work as an anchor in an emergency. . Anchor the boat if necessary.

The Rules of the Road apply when one vessel approaches another, and determine what each vessel must do.

The best defence against collision is keeping a proper lookout at all times by sight and hearing.

Rules of the Road

Meeting Another Vessel Head-On

If two power-driven vessels meet head- If a sailing vessel meets a vessel on, both must give way by altering their engaged in fishing head-on, the sailing course to starboard. vessel must give way. The fishing vessel should maintain its course and speed.

If two fishing vessels meet head-on, both must give way by altering their If a vessel engaged in fishing meets a course to starboard. restricted vessel head-on, the fishing vessel must give way.

If a vessel If a power-driven vessel meets a vessel engaged in fishing meets a vessel not engaged in fishing head-on, the power- under command head-on, the fishing driven vessel must give way. The fishing vessel must give way. vessel should maintain its course and speed.

Crossing the Path of Another Vessel

A power-driven vessel approaching a vessel engaged in fishing on either of its sides must give way.

A power-driven vessel approaching another power-driven vessel on its own starboard side must give way and avoid crossing ahead of the other vessel.

A vessel engaged in fishing approaching a restricted vessel on either of its sides must give way.

A fishing vessel approaching another fishing vessel on its own starboard side must give way.

A vessel engaged in fishing approaching a vessel not under command on either of

its sides must give way.

Overtaking another vessel

Narrow Channels and Traffic Lanes

A vessel is overtaking another when it is coming up with another vessel, from a direction more than 22.5 degrees abaft its beam. The overtaking vessel must keep clear of the stand-on vessel. The A vessel engaged in fishing must not stand-on vessel must maintain its course block the passage of any vessel and speed until the overtaking vessel is navigating in narrow channels. finally past and clear.

Any vessel overtaking another must keep clear of the stand-on vessel.

A vessel engaged in fishing must not block the passage of any vessel navigating in designated traffic lanes.

Lights and Signals

A vessel engaged in fishing other than trawling underway, but not making way through water, with gear extending no more than 150 metres horizontally.

All round red over all round white light

Standard View

Stern View

Bow View

Day Signal

Stability

The stability of a vessel refers to its ability to stay upright in the water.

Many different things can affect the stability of a vessel and cause it to capsize. However, these things can be controlled. A well-designed vessel will not capsize even in the worst conditions - if it is operated properly. The centre of gravity changes, Fishing vessel stability is a very complex depending on how weight is distributed subject. Some basic rules are outlined in the vessel. For example, a heavy load below. For more detailed information placed high on deck will produce a consult a standard stability text book. higher centre of gravity - and less stability - than a load stored below deck.

Centre of Gravity

The centre of gravity (G) is the point at A vessel with a high centre of gravity is which the whole weight of the vessel can "top heavy." If it lists or heels to one be said to act vertically downward. As a side, the centre of gravity pushes down general rule, a lower centre of gravity in the direction of the list. The danger of means a more stable vessel. capsizing is much greater.

The Free Surface Effect

When a vessel with full tanks heels over, the contents of the tank do not shift. The When a vessel with partially filled spaces tank's centre of gravity does not change, heels over, the contents of the spaces so it does not affect the vessel's will shift. The centre of gravity moves stability. over to the side, making the vessel less stable. To avoid this free surface effect, try to have as few partially filled tanks and compartments as possible.

In a partly filled tank or fish hold, the contents will shift with the movement of the boat. This "free surface" effect increases the danger of capsizing.

You cannot always avoid partly filled spaces. By dividing a tank into two equal parts with a baffle, the free surface effect is greatly reduced. Using boards to divide fish wells into compartments will also help.

Loose Water or Fish on Freeboard Deck

A proper freeboard is essential for stability. Freeboard is the distance between the water and the working deck of the vessel. If the deck edge goes under the water when the vessel heels, Fish left loose on deck have the same the danger of capsizing is great. effect as water. Fish should be properly stowed in the hold as soon as possible to maintain stability.

When water is shipped on deck and unable to escape, it creates a large free An overloaded vessel will have too low a surface. It also adds weight high in the freeboard. The deck will submerge with vessel. Freeing ports (scuppers) are vital even a slight heel. Overloading is a for removing shipped water and major cause of fishing vessels capsizing. maintaining stability