Florida Fishing Boats

INVINCIBLE BOAT COMPANY is owned by two South Floridians, Alex Lipworth and Capt. Rob Hammer. The company was formed as each felt there was not a "perfect" boat out there for both the tournament angler who needed speed, and the light tackle guide that needed fishability.

They contacted renowned naval architect Michael Peters and laid out what they wanted to accomplish. The results is a boat that is both fast and dry. What good is fast if you are soaking wet when you arrive at your destination? THE INVINCIBLE'S performance in rough water is outstanding. The deck was designed to fight fish. No pulpits, no bulky gunwales or low decks. Two oversized live wells make the boat more fishable. Rugged construction was required because they knew what tournament fishermen would put their boats through. Finally, it has the fit and finish of the finest boats while having the price that most could afford.

The result is a boat that is unequalled. It's fast- very fast. It's extremely dry and built with the latest technology and best materials in the boating industry. The INVINCIBLE is a true tournament boat that has set a new standard in the industry.

Come and see why the INVINCIBLE is "TWO STEPS AHEAD"

Fast + Dry + Solid + Fishable = INVINCIBLE

Specifications:

Length over all Beam Deadrise at transom Weight Maximum Fuel capacity Horsepower outboard Speed

36' 8" 10' 22 Degrees 9,200lbs. (w/power) 475 1000hp 70+ mph

Salt water washdown
Live well in floor 60 gal.
Live well in transom 50 gal.
Four large fish boxes
Completely finished inside console
Molded stringer system
Cored hull and vacuumed bagged

Our INVINCIBLE open fisherman stands in a class by itself. She is designed to be fished hard and handles a long distance run in rough conditions without giving up comfort or the need for a dry boat.

Every INVINCIBLE is constructed with the finest grade materials with each individual inch, from stem to stern, constructed to keep it balanced and efficient.

best fishing license florida

Guide to Northern Pike Fishing

Imagine planning a fly-in fishing trip for walleyes and northern pike then discovering that not one, but two of this province's premiere fishing lodges are situated on that very lake. Furthermore, indulge in the fantasy that both of those full-services lodges have made a commitment to providing your fishing party with a memorable, relaxing, trouble-free angling vacation on a little-known, top-rated wilderness lake. Yeah, right. Can't be, you say. Verify this data at Nagagami Lake.

Big Nagagami Lake first drew my attention several years ago as we drove north of White River on highway #631 toward Nagagamisis Provincial Park. Considering its sheer size, relative isolation and proximity to Hornepayne's many air services I thought it might have some potential for fishing. But, it wasn't until March '90 at the Toronto Sportsmen's Show that two very reputable fishing lodges - Nagagami Lodge and Timberwolf Lodge - were associated with the lake. Thereupon, like an arrangement of dominoes, everything systematically fell into place and before the show ended, an August booking was mine. And, in order to get a broad view of Liddle's 2-lodge Nagagami Lake operation, the trip would see us split our time and fishing between the two camps. Dave Sauve, Ontario Fisherman field editor and a regular fishing sidekick, eagerly agreed to accompany me on this rather unique angling adventure.

NAGAGAMI LAKE

Nagagami Lake, located approximately 15 air miles northwest of Hornepayne, is a medium-sized, kidney-shaped lake measuring 8 miles in length and 2 to 4 miles in width. The lake shows three distinct areas - the eastern basin, a shallow (20 to 40 ft. ), smooth-bottomed area; the western basin, a deeper (10 to 90 ft. ), irregularly contoured area with islands, rocky shoreline, shoals; a long, narrow, deep (10 to 70 ft. ) northerly arm. Unlike many large, diverse lakes, Nagagami Lake has excellent angling in all three regions:particularly for walleyes and northern pike (although there is a healthy whitefish population and some perch in the lake).

The lake is most unusual in that, in the large eastern basin, a very narrow but productive weedline can be found far offshore where the lake bottom falls from 8 to 12 feet. Because it is well out in the lake and not continuous, finding it becomes on of the keys to the lake's great pike fishing. More on that later!The water is stained from the ever present tannins leaching into the lake from surrounding timber and soils. The lake warms up early for this part of the North and because of its size, can get very rough when the wind blows. There are few boating hazards in the main lake, except along the rugged north-arm shoreline and amongst the island clusters. Isolated hazards are marked by the lodge staff and have been carefully pinpointed on a very detailed, hydro-contour map of Nagagami Lake produced by the lodges for their guests. Key fishing areas are highlighted.

Also accessible (via short, easy portages) are two small lakes:Hiawatha and Pody. Both offer excellent walleye and pike fishing. At Pody Lake, a catch & release lake, monster northerns and bigger than average walleyes are caught regularly.

WALLEYES

With lots of water, diverse structural elements and several incoming & outflowing major rivers, Nagagami is a walleye factory. And, because several lodges and camps operate on the big lake, a river mouth sanctuary policy is in effect on the Foch and Obakamiga ("Buck") Rivers until mid-June. Walleyes are found throughout the lake:in current flows at river sites, along weedlines and in the larger weedbeds, off islands and pointes over gravel bottoms, and on mid-lake structures including several classic shoals, humps, sunken islands, drop-offs and bars.

As suggested earlier, the spring walleye fishery focuses on post-spawn (male) fish, near river outflows. It is not unusual to see a pack of boats in a small area with all anglers catching limits of walleyes and releasing many fish. Springtime is minnow time and Nagagami is a "minnow lake" all season long. To protect the lake, minnows are carefully collected and sorted before being flown into the camps for fishing. Rigged on small snelled hooks, live-bait rigs or tiny jigs, minnows are fished at the mouths of rivers where deeper areas have been created by the current or along current breaks/eddies. Other productive springtime/early summer walleye locations include the island group out from Pody Creek, an area designated "The Flats" and the upper portion of the out-flowing Nagagami River (as far downstream as Moose Lake).

Summer walleyes are widely scattered and predictable, low-light feeders. Three approaches are commonly used by Nagagami & Timberwolf Lodge guests:stillfishing minnows, backtrolling with live-bait rigs, and jigging. Standard, forward trolling with wobbling plugs or body baits is almost unheard of here.

For both experienced anglers and vacationing families with kids at Nagagami Lodge, stillfishing minnows was a popular and effective technique. Whether anglers positioned themselves out from a weedline or weedbed, along a dropoff that fell to 20 or 30 foot depths or atop the sunken islands and shoals, limits of great-eating walleyes in the 1 to 3 pound range were the rule-day after day. Best times included the early morning hours, but the twilight times were tops. Daytime fishing was given over to pike. Dave and I took a lot of kidding about our fishing off the dock at night with floats/bobbers. That's OK. Each night without fail (about 10:30) we'd slip down to the camp dock and catch 3 or 4 good walleye for breakfast. By 1:00 or so we'd caught our fish and were enjoying no-less-than-spectacular displays of shimmering Northern Lights. Those evenings may have been the most enjoyable I spent all summer; they certainly were unforgettable!Get a second opinion - ask Dave!

Both Mike Bauer and Ron Dunn, managers of the two lodges, effective fished walleyes the same way:back-trolling across mid-lake shoals with live-bait rigs dressed with minnows. For this approach a depthfinder/flasher/graph is a must for locating the structure and then systematically working the bait rig up and down it until fish are contacted. Favourite spots included a large, marked shoal northeast of the Twin Islands, the "Banana Shoal" beyond that, and isolated humps in the main-lake basin including one off Chuck's Point and another in the midst of the lake's eastern basin. The latter spot is tough to locate. Mike put us onto it in a driving rain one morning. S ure that he was "testing our resolve and mettle", we dutifully backtrolled this spot in the middle of nowhere. Bingo-several larger walleyes! Touche, Mike, but couldn't it have waited?

Although live-bait fishing is the norm at Nagagami, jigging accounts for excellent catches of "yellows". Location is the key to successful jigging:over shoals/humps/sunken islands or along weedlines and dropoffs. Any significant change in depth, bottom content or cover will attract and hold walleyes, especially during feeding periods. For Nagagami Lake walleyes, pink, white and yellow jigs in the 1/8 to 1/4 ounce sizes are recommended with pink getting the nod most times. Tipped with a small piece of worm or a lively minnow, jigs should be cast and worked down ledges and humps, jigged in short hops off deeper bottoms or cast and retrieved steadily over shallow (6 to 10 feet) bars. On our sidetrip to Hiawatha Lake, drifting a jig & worm combo proved the undoing of scores of walleyes. Our best catches (biggest fish) came off the head of the Banana Shoal where we carefully located and marked a "bite" out of an otherwise regular edge. Everytime we drifted to that spot we picked up fish, including the three largest fish of our stay and the largest caught at camp that week. A tiny "something special" spot.

Don't overlook weedbeds and weedlines as good spots for walleyes. One party at camp ceremoniously located, marked and fished a weedline at The Meadows and consistently caught limits of better-than-average walleyes. Fish were right in there, at the base of the weeds in the only cover in that part of the lake. To get these fish, baits had to get right in, amidst the stems and stalks; sometimes only to be grabbed first by Nagagami's opportunistic pike. Hey, that's OK, too!

While at Nagagami, don't pass up the incredible shore lunch fish fries put on at midweek by Nagagami Lodge and daily (weather permitting) by Timberwolf Lodge staff at the Twin Islands. The great outdoors, good friends and a hot shore lunch - "It doesn't get any better than this"!

NORTHERN PIKE

During our stay at Nagagami, one thing became abundantly clear:pike fishing was given high priority by visiting anglers, especially "repeaters" who were not only familiar with the lake's pike hotspots, but also very much aware of the potential for a mammoth northern pike-fish in the 20 to 30 pound range. In fact, while having dinner at Timberwolf Lodge one evening, one of the "regulars" made a point of coming over to us and showing us pictures of past catches of huge Nagagami pike. This was prompted, no doubt, by her excitement over having just caught a magnificent 44-inch, 20-plus pound pike at The Meadows, an extensive weedy area off the Nagagami River outlet. Not an uncommon fish out of Nagagami Lake; uncommon just about everywhere else.

Because pike, like walleyes, are predatory fish, their seasonal movements and feeding habits often parallel those of walleye. Very often, where walleyes are caught, big pike are caught, even on the same baits. Resultantly, Nagagami northerns are fished with live baits early and late in the season and with artificial baits or lures through the warm-water months.

Come spring, pike are the lake's first spawners and most aggressive fish. Immediately after the spawn, pike will begin taking live-bait offerings at typical springtime sites:weedy back bays and creek/river outflows. Top spots at Nagagami Lake include the Pody Creek area and a channel nearby appropriately dubbed "Pike Alley". Large live baitfish, especially suckers, regularly produce the biggest pike in the early season, although occasional monsters will be caught by walleye fishermen, too.

Once the water warms, pike will scatter widely throughout the lake-to weedbeds/weedlines, shoals, current flows and deep-water basins - wherever their forage, oxygen and temperature requirements are met. It is at this time that fish start chasing down larger, faster-moving baits - e. g. spinners, spoons, bass spinnerbaits, bucktails and jerkbaits. At Nagagami, this period puts fish in the weeds and anglers looking for the lake's strange offshore weedlines. Once found, these weedlines consistently produce lots of healthy northerns:fish averaging 5 to 8 pounds. Both our hosts knew these weedlines well and unerringly kept us near them and "on pike". Ron is a diehard pike fanatic and spoke constantly of the lake's bigger northerns:historic catches, fish hooked and lost, the season's best, the lake's potential for a 50-inch, 30-pound gator!

The 44-inch fish mentioned earlier was caught on a bass spinnerbait, yet we took our best pike on spoons and spinners. However, Ron insisted that, if you were to fish strictly for a trophy, a jerkbait worked over and near the weeds would be the most productive lure. To be sure, he had a collection of these wooden freaks - baits in the 7 to 9-inch range worked best. Oh sure, he had a couple of "baseball bats" in there, too. Proven choices at Nagagami Lake include Suicks, Teddy Baits, Reef Hawgs and Hi-Fin Foolers. Casting and working these baits is hard work, so if you troll try a Believer, Swimm Whizz, Magnum Rapala or huge, jointed Kwikfish. Make sure that your equipment can handle this kind of tackle and strain before experiencing a day of frustration or worse, losing the fish of a lifetime.

As stated a moment ago, Dave and I successfully pitched #4 or 5 Mepps Agilia Long/Giant Killer spinners and large spoons (Daredevle, Five Diamonds) to the lake's weed-oriented pike. By simply moving around the perimeter of the eastern basin, fishing the intermittent weedline, we enjoyed fast-paced pike action throughout the afternoon. When fishing pike like this, please equip yourself with proper tools for extracting deeply taken baites from cavernous, toothy mouths - a "gag" to hold the fish's mouth open, long-reach hookouts, pliers or cutters. The careful and quick removal of hooks and immediate boatside resuscitation will insure a successful release of fish not intended for the dinner table. Sensible catch and release is an art form as much as it is a science.

Two other areas deserve special recognition when it comes to Nagagami pike fishing:The Meadows and Pike Alley. With current flows and plenty of weed cover, these areas consistently produce lots of pike as well as trophy-status fish. Bass spinnerbaits, jerkbaits, spinners, spoons and bucktails will get plenty of attention from big, aggressive northerns. Hang on!

WHITEFISH

Although many northern lakes have very healthy whitefish populations, they are pretty much underfished. At Nagagami Lake during late August through mid-September, whitefish action is outstanding and the lodges offer a continuous smokehouse service to their clientele. Smoked whitefish makes for great eating, keeps well and increases each angler's legal "keep". With generous limits and regulated dip netting practices to supplement angling, "whitefish-ing" should be added to the itinerary for late-season guests at Nagagami and Timberwolf Lodges.

NAGAGAMI LODGE

Located on the northern arm of Nagagami Lake, this 2-star housekeeping resort features superb facilities:spacious, modern log cottages, generated hydro, sturdy 19-foot Powassan cedar-strip boats, reliable OMC motors, a central recreation lodge/meeting area with VCR/movies/TV and a pool table, guide service, bait, fish-cleaning station, smokehouse, etc. Cabins feature 2 or 3 bedrooms, bedding & liner service, modern full-size appliances, wood-burning heaters, 3-piece bath (shower, flush toilet, sink), running hot and cold water, electrical lighting, complete kitchens.

Air Service to Nagagami Lake is provided by Horne-Air (Hornepayne, Ont.) via Beaver aircraft.

Amazing Fishes

All of us have seen fish. They are very elegant in their colouration and many people like to keep them as pets. A fish may be identified as an aquatic vertebrate animal whose body may or may not be covered by scales and bears two sets of paired fins and many unpaired fins. fish are cold blooded or ectothermic animals which mean that their body temperature keeps on changing with the temperature of water. fish are distributed in all aquatic habitats ranging from the mountain streams to the deepest oceans. About 32,500 species of fish are known and they together form the largest diversity of the organisms in comparison to other classes of vertebrates. fish are also caught by the fish keepers and are kept in aquaria as a source of decoration. They are also associated with movies, cultures and religions.

The term fish applies to an animal which suggests any non-tetrapod craniate that bears gills throughout its life and has fins instead of limbs. Like other vertebrates fish are of different types and are classified according to their characters. The main types of fish found in the modern world are the hagfish, sharks, rays, lampreys, ray-finned fish, coelacanths and lungfish. A fish possesses streamlined body to swim rapidly in the aquatic environment, has gills or accessory respiratory organs for getting oxygen and have paired as well as unpaired fins. The paired fins include the pectoral and the pelvic fins. The unpaired fins are the dorsal, anal and the caudal fins. Generally the body of the fish is covered with scales but there are some fish also which lack scales and are scale less. The jaws are very well developed in the fish. They are oviparous.

Generally fish are cold blooded vertebrates but exceptions always exist. Tuna, swordfish and some species of sharks have adaptations towards the warm blooded category. The streamlining and the swimming efficiency of the fish also varies for example tuna, salmon and jacks can swim 10-20 body lengths per second while the eels and sharks cannot move more than 0.5 body lengths per second. Some species of fish have the capability of extracting oxygen directly from the air as well as through other substances as they bear some specialized structures for this purpose for example lungfish have paired lungs, gouramis have labyrinth and catfish extract oxygen through the intestine or the stomach. The shape of the body as well as the arrangement of the fins is also variable. The scales are of different types like the placoid, cosmoid, ganoid, cycloid and ctenoid. There are certain fish also which live on land like the mudskippers which live on the mudflats and on being disturbed hide themselves in their underground burrows.

The body size of the fish varies from as small as the stout infant fish which is only 8mm long to as huge as the white shark which is 16meter long. Many animals are often confused with fish as the term fish is associated with them like the starfish, jellyfish, cuttlefish, shellfish. Strictly speaking they are not fish. There are at present 28,000 extant fish of which 27,000 are the bony fish, 970 are the sharks, rays and chimeras and 108 are the hagfish.

About 64 families of fish are monotypic as they contain only one species. The overall total of the fish comes to about 32,500 at present.

fish respire through gills present on either side of the pharynx. The gills are made up of thread-like structure known as filaments. Each filament is supplied by the capillary network which increases the surface area for the easy exchange of oxygen and carbon dioxide. fish draw the oxygen rich water through their mouth and pump it over the gills. In some fish the capillary blood flows in opposite direction through counter current system. The gills pass the water poor in oxygen to the gill openings present on the sides of the pharynx. Sharks and lampreys have multiple gill openings while some fish have single gill opening. The gill openings are covered by a protective covering called as operculum.

The breathing mechanism is also variable in fish. The skin of anguillid eels has the ability to absorb oxygen. The buccal cavity of the electric eel has the potential to absorb oxygen. Some fish like the perches, cichlids are also able to breathe air directly but majority of the fish are dependent on the oxygen dissolved in water. Some air breathing fish also hide themselves under the moist burrows and show a temporary hibernation mechanism and when plenty of water is available they show aestivation by returning to water. fish may be obligate or facultative air breathers. The African lungfish comes under the category of obligate air breathers as it comes to the surface of water for gulping out air otherwise it will die due to suffocation. Facultative air breathers comprise the heavy section of the fish as most of the fish breathe oxygen dissolved in water as they conserve energy by not coming to the surface of water to gulp air. The catfish in absence of dissolved oxygen can rely on oxygen dissolved in gills.

The circulatory system of the fish is in the form of a closed loop. The heart pumps blood through this single loop to the whole body. The fish heart consists of four parts including two chambers, one entrance and one exit opening. The first part of the heart is the sinus venosus which is a thin walled sac and collects blood from the veins of the body before passing it to the second part which is atrium. Atrium is a large muscular chamber which sends blood to the third part which is the ventricle. The ventricle is thick walled and it passes blood to the fourth part the bulbous arteriosus. From here the blood is passed to the aorta and then to the gills for oxygenation.

Jaws in fish are very well developed and allow them to eat a wide variety of food materials whether it is a plant or an animal. Ingestion of food occurs through the mouth and it is broken down into the oesophagus. The digestion of food occurs in the stomach and in some fish characteristic finger like projection are present which secrete the digestive enzymes. These projections are called as pyloric caeca. Pancreas and liver also secrete enzymes and help in the easy digestion of the food material. The whole process of digestion and absorption ends in the intestine. The waste material of fish is rich in ammonia which means they are ammonotelic. The waste material leaves the body either through the gills or through the kidneys. Saltwater fish lose water through osmosis and reverse happens in case of freshwater fish. The kidneys excrete dilute quantity of urine. The scales in fish originate from the skin.

The brain of fish is comparatively very small as compared to other vertebrates but some larger fish like the sharks, mormyrids have larger brains as compared to that of the birds. The fish brain is made up of several parts. The front region is occupied by the olfactory lobes which receive and process the signals from the nostrils via two olfactory nerves. The olfactory lobes are generally very large in sharks, hagfish and catfish as they depend solely on smell for catching their prey. Right behind the olfactory lobes is a two-lobed structure called as the telencephalon which is equivalent to the cerebrum of higher vertebrates. It is associated with olfaction. Both the olfactory lobes and the telencepahlon comprise the forebrain of fish.

The forebrain is connected to the midbrain via diencephalon. Diencephalon controls the function of hormone regulation and homeostasis maintenance. Pineal body is present just above the diencephalon and it detects the light changes, circadian rhythms and colour changes. The midbrain or mesencephalon consists of two optic lobes which are large in those fish which hunt by sight like the rainbow trout and the cichlids. The hindbrain or the metencephalon performs the function of swimming and balance maintenance. The cerebellum is the largest structure of the brain and it is single lobed. Hagfish and lampreys have small cerebellae while mormyrids have heavy cerebellae as it is associated with their electrical senses. The posterior part of the brain is the brain stem or the myelencephalon. It governs the functions of muscle coordination along with respiration and osmoregulation.

Most fish have very well developed sense organs. All the diurnal fish have well developed colour vision. Many fish are gifted with chemoreceptors that are responsible for extraordinary senses of taste and smell. Although fish possess ears but they are not able to hear well. The sensory receptors form the lateral line system in fish which detects minute currents and vibrations as well as movements of the nearby prey. Sharks and catfish can also detect low-level electric currents. Electric eels produce electric currents. Experiments have revealed that fish have good powers of learning and memory.

The experiment conducted by William Tavolga on the toadfish suggests that fish have the ability for pain and fear responses. According to a study performed by the Scottish researchers at the University of Edinburg and Roslin Institute on the rainbow trout in 2003 suggests that it shows behaviour associated with pain like other animals. The researchers injected bee venom and acetic acid in the lips of the rainbow trout. The fish immediately started rubbing its lips on the walls of the tank and this response was taken as the behaviour towards relieving pain by the researchers. The firing of the neurons resembles similar as found in humans. Professor James D. Rose however, argues that fish do not feel pain as they lack neocortex.

Fish have paired set of alternately arranged contacting muscles on both the sides of the backbone. These contracting muscles form S-shaped curves which move down to the body and help in swimming. Fins also increase the tail surface area for effective swimming. Streamlined body reduces the force of friction. Many bony fish have a swim bladder which is filled with gases and helps in maintaining buoyancy. Although fish are ectothermic but exceptions always exist. Some fish are amphibious also like the mudskippers. Some fish maintain their body temperatures at a higher range. All sharks of the family Lamnidae are endothermic. The degree of endothermy varies in different fish, although it is costly but it provides the advantages like increased muscle strength, higher rates of central nervous system processing and higher rates of digestion.

The reproductive organs of the fish include testes and ovaries. In majority of species the gonads are of similar size and they may be partially or totally fused. Secondary sex organs are also associated with the reproductive organs in order to increase its fitness. In terms of spermatogonia distribution two types of testes are found in the teleosts. In the first type the testes are found all along the seminiferous tubules while in other type testes is present along with the distal portion of the seminiferous tubules. The ovaries in fish are of three types. They may be gymnovarian, secondary gymnovarian and cystovarian. In the gymnovarian ovary the oocytes are released directly into the coelomic cavity from where they enter the ostium and are finally eliminated through the oviduct. Secondary gymnovarian ovary releases ova into the coelom from where they enter directly into the oviduct. Gymnovarian ovaries are primitive typwe ofd ovaries present in the lungfish, sturgeons and the bowfins. Cystovarian kidneys are the characteristics of the majority of teleosts as here the ovary is directly connected with the oviduct.

The development of the oogonia differs in different groups of fish and it provides the details of the maturation as well as fertilization process. Changes in the nucleus, ooplasm and surrounding layers determine the maturation of the oocyte. The postovulatory structures that are formed after the release of the oocytes are absorbed by the process of apoptosis. Some fish are hermaphrodite as they have both the testes and ovaries in their bodies at different stages of their life cycle. About 97% of the fish are oviparous. The common oviparous fish are eels, tuna, goldfish, cichlids and salmon. In these fish fertilization occurs outside the body of the mother as both the parents shed their gametes in the surrounding water. Some oviparous fish also practice internal fertilization method as the male uses some sort of intromittent organ for delivering sperms into the genital opening of the female. Skates and horn sharks come under this category. In these fish male uses claspers for delivering the sperms into the female's body.

Marine fish produce large number of eggs in the open water column and the diameter of eggs is about 1mm. The newly hatched young ones of the oviparous fish are called as larvae. They are very delicate and carry a yolk sac for their nourishment and are very different in appearance as compared to the adults. The larval period is very short and the larvae rapidly lose their yolk sac and grow to juvenile stage and start feeding on the zooplanktons. Since the zooplanktons are present in insufficient quantity many juveniles lose their lives due to starvation. Guppies, coelacanths and the angel sharks are ovoviviparous. Here the eggs develop inside the mother's body after the internal fertilization and receive only yolk as a means of nutrition.

Some species are viviparous. In some species the mother retains the eggs and nourishes the embryos. Lemon sharks, splitfins and surf-perches are typically viviparous fish here the embryo receives nourishment through a placenta like structure as found in mammals. In some viviparous sharks the developing embryos eat other eggs produced by the mother and this phenomenon is called as oophagy. The young ones of the grey nurse show intrauterine cannibalism where the stronger young one devours weaker siblings. The immune system of fish is also variable. The jawless fish lack true lymphoid organs. The erythrocytes, macrophages and the plasma cells are produced in the anterior part of the kidney and somewhere in the gut and they bear close resemblance with the bone marrow as in case of the hagfish. The cartilaginous fish have well developed immune system and the epigonal organ surrounding the gonads, Leydig's organ within the walls of the intestine and the spiral valve of the intestine are responsible for the production of the immune cells. The cartilaginous fish have well developed spleen and thymus gland which produce lymphocytes, macrophages and the plasma cells. The bony fish show further advancement in case of immune system. Apart from the spleen and the thymus gland, scattered mucosal cells in bony fish also act as immune tissues.

Like other animals fish also suffer from the attack of parasites as well as diseases. To remain free from diseases they have well developed defence system. The skin and the scales as well as the mucous secreted by the epidermis prevent the entry of micro-organisms inside the body of fish. The immune system also plays an essential role in fighting against the infections. The fish are believed to have evolved from the coral-like sea squirt.

According to a report of IUCN in 2006, 1,173 species of fish are under the danger of being extinct. White sharks, Atlantic cod, Devil's Hole pupfish are some of the threatened species. Overfishing is the very dangerous enemy of cod and tuna. Overfishing is responsible for the population collapse of fish as the progeny production is at risk.

Water pollution, construction of dams, removal of water for human utilization and introduction of the exotic species is also responsible for habitat destruction of the native species and all this leads to population declination of fish. The introduction of the Nile perch in the Victoria Lake has exterminated the cichlid population of the lake.

Fish have also been found associated with the culture and religion. The assemblage of fish in an area merely for a matter of feeding and nesting is termed as aggregation. Fish shoals or schools are formed depending on the degree of their organization. Shoals are loose organizations where a fish adjusts its behaviour and swimming movements in response to the others members of a group. Schools of fish are tight organizations comprising all the movements and other activities in the same direction. Both shoals and schools benefit the fish in many ways.

Fish Oil And Depression

It seems that everyone is talking about Omega 3 these days and the positive effect that fish oil can have on a whole range of health problems. The media continue to report on how fish oil can protect against heart disease, reduce inflammation, boost the immune system and how it can improve brain function in general so it should come as no surprise to any of us that the evidence also shows that fish oil can have a dramatic effect on depression and other mood related disorders. Why?

Some of us will have already heard that fish oil is brain food and in a way, that's exactly what it is. Not only is the brain largely composed of fat, it needs the Omega 3 fatty acids found in fish oil in order to work properly too. Interestingly, people who are suffering from depression, ADHD, Alzheimer's disease and other brain-related conditions have been found to have low concentrations of the essential Omega 3 fatty acids in their blood, particularly Eicosapentaenoic acid or EPA and perhaps this is no coincidence.

No one really knows the exact mechanisms involved or how it works but the indications are that EPA thins the blood and helps it to flow more efficiently to the brain, enhances inter neural connectivity, increases serotonin levels, reduces inflammation, improves concentration and memory and even has a mood elevating effect. Consequently, it stands to reason that supplementing with fish oil might alleviate symptoms of depression and this is just what researchers have been finding out.

What the research says...

A Harvard study led by Dr Andrew Stoll in 1999 reported that fish oil can dramatically improve symptoms of Bipolar disorder (manic depression). Bipolar disorder is a type of depression manifesting itself as repeated episodes of depression and mania or both and it can have a devastating effect on the life of the individual and their loved ones. In Stoll's study, 30 bipolar patients with a history of relapses were given either fish oil or a placebo in the form of Olive oil. The trial was supposed to last for 9 months but was stopped after 4 months due to the dramatic results of the fish oil group who were able to reduce their symptoms of depression and stay in remission significantly longer than the placebo group.

Then in 2002 researchers Peet and Horrobin tested the antidepressant effect of ethyl EPA, a particularly concentrated form of EPA, and found that a dose of 1 gram daily was effective against depression. Participants were assigned either to the fish oil group or the placebo group and given various doses of fish oil daily for 12 weeks. At the end of the trial, those taking 1 gram of fish oil showed a significant improvement over those in the placebo group and the conclusion was that this dose was particularly effective in treating people with persistent depression.

Yet another study by Puri et al involved giving EPA in addition to normal medication to a suicidal male patient suffering from severe depression. Not only was there a cessation of suicidal ideation and an improvement in all the symptoms of depression, but brain scans carried out before and at the end of the trial indicated structural changes to the brain after taking EPA. This study also suggested that EPA might enhance the efficacy of other medication for depression.

Other studies have revealed that there is a higher incidence of postnatal depression in countries with a lower level of fish consumption. This makes a lot of sense when we consider that Omega 3 fatty acids are particularly important during pregnancy and in the first few years of a child's life when the brain is developing very rapidly and if the mother doesn't get enough fatty acids whilst pregnant, she can find her supplies depleted as they are transferred to baby.

Here in the UK, the Durham trials are consistently reporting on the positive effect that fish oil can have on behaviour, concentration and learning in the classroom and an Australian study led by researcher Natalie Sinn even reported that fish oil was more effective than Ritalin for Attention Deficit Hyperactivity Disorder or ADHD.

Conclusion

It would be reasonable then to conclude that a lack of Omega 3 fatty acids in the diet or perhaps even a higher than normal requirement for Omega 3 fatty acids can result in low fatty acid concentrations in the brain, which of course might increase the risk of depression and other related disorders. Depression can affect any one of us at any time, it is indiscriminate of age, background or gender and the numbers are increasing year after year.

Could it be that an overall reduction in consumption of fish and therefore Omega 3 fatty acids might be contributing in some way to a rise in cases of depression? The evidence isn't conclusive but the indications are that fatty acids certainly have a role to play in the prevention and treatment of all kinds of depression and mood related disorders. Research in this area is growing rapidly and no doubt we will be hearing a lot more about the benefits of Omega 3 and EPA in the future. In the meantime, fish oil is a safe and convenient supplement that can be taken by everyone to improve health in general.