About the blue shark
The blue shark is the more common of the big four sharks that are proven to visit the UK and Ireland annually alongside the porbeagle, thresher and mako. Although the effects of commercial long-lining and general over-fishing had a major effect on blue shark numbers through the 1990s and 2000’s inducing an inevitable serious overall decline, although not eradicated, the pressure of commercial fishing has eased somewhat of late and their numbers are now bouncing back.
This has been reflected in the average size of the blue sharks caught off the UK and Ireland. In the 1990s and first decade of the millennium, the average size of blue sharks was around 40lbs. Currently, in 2020, the average size is higher and around 60lbs with a higher number of bigger fish of 100lbs recorded. In recent years, the old blue shark record at 218lbs, which has stood since 1959, has been shaken by several fish over 200lbs and two definite fish that have easily exceeded that weight including one estimated by reliable eyes at the boat side at around 250lbs. The modern practice of total catch and release means these fish were not claimed as records, but it proves the point that blue shark fishing is on an upward peak and the prospects for the future are positive.
The male blue shark grows to a maximum size of around 9.5ft and maybe 300lbs or so in weight, but the females can grow to 12ft and with a more rounded body shape they can achieve weights closer to 500lbs. There have been commercially proven fish bigger than this including a female apparently weighing 862lbs and around 15ft in length.
Female blues achieve maturity at five to six years of age, males at between four and five years. The females can give birth to 100 to 130 live young, but this number is very much dependent on the size of the actual mother, obviously, the bigger females having the biggest litters and smaller fish far fewer from four to maybe 60 as a guideline. The young are between 15ins and 18ins in length when born and instantly capable of fending for themselves.
Studies have shown that the majority of females that visit our waters are immature and the proportion of males to females is as low as 1 per 5000 sharks in the southern English Channel. A small proportion of the larger sharks caught can be females that have pupped previously.
The superb results achieved by the tagging of blue sharks by the Irish Fisheries Boards has yielded some fascinating evidence of blue sharks travelling from Irish waters to the Azores and proving there is some interchange of sharks across the Atlantic Ocean east to west to North America. Tagged sharks have also travelled as far as South Africa. They are true ocean wanderers!
How to identify a blue shark
The blue shark is virtually impossible to mistake with any other shark. It’s unmistakable long elongated body with a large upper lobe to the tail and the very long pectoral fins make identification easy. The nose is long and sharply pointed and it has 5-gill slits.
The biggest giveaway is the serrated cutting edges to the pointed teeth. The teeth are ultra-sharp and any wounds from these when handling the fish can take a long period to heal due to the teeth being armed with an anticoagulant.
The colouration in the water, and even when on deck being measured and tagged, is a distinctive indigo blue and the origin of the sharks’ name. The sides shade to a lighter blue and then silvery-white on the belly. Some blues that have come up quickly from deeper water will have a darker blue coloured back, but this quickly lightens when they stay near the surface for a while.
The blue shark has a near worldwide distribution in temperate and tropical seas and is one of the world’s commonest sharks.
They are found all around the UK, but much less so in the North Sea. They will also travel as far as The Shetlands and maybe The Faroes occasionally and have been recorded off the southern Norwegian coast. They are found all around Ireland too but are commonest off the southern and western coasts as high as Donegal.
A key indicator to their proximity to shore is the overall depth. They prefer water in excess of 200ft and are rarely found in lesser depths, though diseased or confused fish can sometimes be seen swimming along beaches in shallow depths, this is not common. They can tolerate depths down to 1200ft but are generally a near surface-dwelling shark within 400-feet of the surface.
Their ideal temperature range is between 12C and 20C, and in the UK they tend to appear when the sea temperature hits that 12C banding.
In the south of the UK and Ireland, blues have been recorded in late May after very mild winters, but the main season will be from mid June with a rapid increase in numbers through July and into August. September is an excellent month to be targeting blues, and they will stay well into October in the south, even early November if the autumn is settled and warm.
Off Northern Ireland and the west of Scotland, the blues appear later, usually around late June or early July and will disappear again around late September. A few blues will filter in, mainly from the north through the Pentland Firth, into the North Sea. These tend to be single fish and bigger females. This tends to occur from late August and throughout September.
Blue shark diet
Blue sharks are opportunists and will feed literally on whatever is available to them. Their common diet is shoaling fish such as mackerel, herring and pilchard, but they will also dive deep for squid when these are prolific.
They have also become educated to the fact that trawlers when hauling nets will drop loose fish and they will congregate in large numbers in areas where trailers are working feeding off the discards.
They have also been found to drop down onto the seabed and take flatfish, and have also been seen to stalk seabirds floating on the surface. In fact, the Talk Sea Fishing team have witnessed blues throwing up bunches of feathers and bird carcasses when on deck being tagged and measured prior to release. They have also been seen eating dead whale meat from whale bodies floating on the surface, also dead seals.
They have also been seen to take sunfish off the surface, and have also been observed forming small packs and herding up prey fish to make the feeding easier for the benefit of all the sharks in that pack. Blue sharks have also been filmed coming together in large numbers to feed on whale carcasses that have fallen to the seabed in deeper water.
They have the ability to smell tiny amounts of blood and fish scent from at least a quarter of a mile away, their sense of smell being hundreds of times better than that of a human.
The blue shark is also equipped with sensory organs called electroreceptors that form a network of jelly-filled canals ending in open pores on the skin. These are distributed around the mouth and head and are capable of picking up small electrical distress signals from wounded fish, but also to detect the magnetic fields around the earth which enables the sharks to navigate and detect temperature changes.
Another advantage for the blue shark is its lateral line. Again this is a continuation of pores that run all the way from the snout to the tail. As the shark swims, water flows over these pores and the sensory cells detect pressure changes but also gives the shark spatial awareness of its surroundings by waves it creates when swimming that bounce off and back to the shark from nearby features allowing it to build up a picture of its surroundings using its own sonar system. This is possible because of the dense nature of water compared to thin air.
Their common habitat is in the sub-surface water column in the open ocean where the average depth is at least 300ft and ideally deeper. It’s not really a rule of thumb, but their habit is to be roughly mid-water to one-third depth. That said they are very happy to come up right to the surface and you’ll often see their dorsal fin cutting through the surface water as they head towards the boat just to have a look at what’s going on.
In normal times, when shoal fish are plentiful, they will be in that mid to upper water column. But if shoal fish are scarce, then they will drop to the seabed and feed over clean sand taking whiting and other smaller species, or, they have been known to work over rough ground closer inshore taking smaller species such as pollack.
A good place to target blues is if you can locate an area of upwelling currents that are pushed up towards the surface by rising ground features such as rocky peaks or ledges. These concentrate the shoals of baitfish, and in turn, pull in the sharks.
Blues can also sometimes be found working around wrecks, again because these aggregate a large number of fish making feeding easier.
Tides and fishing for blue shark
Even though they are an offshore shark, tides are still important when targeting them, especially as we, as anglers, are technically hunting them on the very edge of their inward migration along the coast where tidal influence is greater.
Blue sharks can be caught on any size of tide, even the smaller neap tides, but generally, they feed better and travel further during the bigger spring tides. If it’s possible, try to book tides that are the middle-sized tides rising towards spring tides or the biggest tides. This increasing tidal flow excites the sharks and brings in the shoal fish, hence the sharks are more active and hunting for food. Once the tide goes over their peak, expect catches to drop back and continue to do so as the tides get smaller towards the lowest neap tides.
The stage of the tide is important too. The Talk Sea Fishing team have looked back at their catch diaries going back well over 30-years and the pages clearly show that the best of the fishing is through the middle hours of the flood when the tide is picking up and flowing strongest. During slack water, catches can be made but are less likely. The middle flow of the ebbing tide can also see an increase in catches, but in most areas results will be less than during a flooding tide.
The tide is also very important in how the rubby dubby or chum trail, this being a mix of mashed up fish, oil and bran to bring the sharks in, works in the water. We’ll look at this in detail in a separate section, but in short, the faster the tide, the more the rubby dubby gets distributed with the ability to bring sharks in from much further afield.
During periods of very rough or stormy weather, the baitfish shoals get scattered into much smaller groups and this means the sharks have to roam far and wide to locate their food. This, in turn, sees the sharks in a specific area fewer in number. After prolonged periods of rough seas, then expect the sharking to be slow at best. It usually takes three or four days of a settling sea to see the shoal fish and the sharks start to regroup.
The very best weather patterns are relatively settled weather periods with mild onshore winds and a light to medium sea swell. Add some overcast cloud cover and you’ve got the perfect conditions. The cloud cover reduces light penetration through the upper water column, plus the cloud cover acts as a silhouette enhancer for the sharks looking up with which to identify their prey. The sea swell and confused surface water also cuts the penetrating light levels down and makes the sharks less cautious of coming up in the water column.
Even rougher seas can fish well and this can be for several reasons. One of reduced light levels bringing up both the shoal fish and the sharks. There is more noise from the hull of the boat which can bring fish in for a look based on the trawler scenario, plus the rubby dubby works well and gets well distributed. Also, the balloons that suspend the baits at depth are lifting up and down with the swells and this gives the dead bait more life and it acts more natural to a feeding shark.
Blue shark tackle
Shark tackle has moved on from the huge 6/0 Penn Senator reels, 80lb line and car handbrake wire cable traces that used to be the norm. Nowadays, shark anglers tend to fish far more sporting tackle that maximises the fun of the fight, but still has the power to quickly subdue the shark. If you’re new to shark fishing though, then most anglers would be wise to use the boat’s own tackle for the first few trips and get a feel for how they want to fish.
However, some of the tackle you already own will be fine for basic blue shark fishing. Given that the average blue weighs around the 60lb mark, and fish over 100lbs are less likely, a standard 30lb class boat rod about 7ft 6in to 8ft in length is perfect for beginners. The reel to go with this would be a multiplier, either a star drag reel or a lever drag such as the Penn Fathom 30LD or the Penn Fathom 2 star drag 30 size to compare others with. These reels will take over 400yds of 30lb line, have a brilliant drag system which is very important, plus holds more than enough line, even for very big fish, plus they are tough and can take the rigours of shark fishing.
As you get more proficient in playing sharks, then the best tackle choice is 20lb class. This is light enough to give maximum sport, but in the right hands will land any blue shark that swims in UK waters, plus will have enough to land even porbeagles in the 200lb class and bigger should one happen along.
When going to this lighter class of rod, think carefully about the action you choose. Stiff rods are a natural choice, but in reality, a more modern soft tip action with power creeping into the upper mid-section and with power increasing quickly into the lower mid-section and finishing with a short stiff butt section is a far better choice when fishing these lighter lines. The soft tip and gradual transfer of power in the more powerful lower mid-section is key in playing the fish out properly. The supple tip cushions the strong lunges of the shark, plus helps tire it far quicker than a stiff rod will. With the rod bent, the transitional upper and lower mid-section apply the shock-absorbing effect that really keeps pressure on the fish soaking up its pressure and making it work hard thus tiring it quicker. The stiff butt section is the steerage which as pressure is transferred into this the rod starts to lock up providing that steerage and leverage to control a fish as it gets close to the boat.
One last word on rods is that there is little advantage in having rods with roller rings on. Again, this is an over-heavy approach for fish that are unlikely to run much over 100lbs for the majority of anglers. Standard open rod rings are just as good for this class of fishing but do make sure they are a strong framed pattern and be wary of tip rings that rely only on a soldered wire stabilizer formed over the tube of the tip ring. Cheaper versions of these can give and break when under heavy pressure.
Reels in this lighter class need to be chosen on drag capability and gear strength. Reels that cut the mustard will be from Penn, Shimano and Daiwa, proven names to judge all others by. The Penn Squall 20 Star Drag reels are the right size and balance well on 20lb class rods, plus they hold close to 400yds of 20lb mono, again a reel you can judge others by. Alternatively, if you feel more secure with more line, then use the 30 sized reels but load with 20 to 25lb mono.
Experienced anglers also tend to prefer a lever drag for its improved performance and ability to give line without hesitation which can be so important when playing big fish like sharks that can crash dive suddenly. Equally, a 2-speed reel can be useful allowing you to drop down to a much lower gear to bring a big heavy fish up from deep down when it just hangs there, which some big sharks can do.
The big question is mono or braid? Actually, it’s very straight forward. When shark fishing, go for the monofilament every time. As good as braids are for general fishing it is not good for sharks. There is no elasticity in braid therefore the hook hold comes under maximum pressure when a shark turns and dives. This can overstrain knots and cause a weak hold to give. Braid also has a tendency to dig into itself when loaded on the spool under heavy pressure such as playing a large fish. This will cause issues when the fish next wants to take line and can cause line breakages. The stretch in mono in this instance is an advantage as we’re not trying to fish at depth in a fast tide and the stretch in mono helps preserve a light hook hold, plus the give and take pressure exerted by mono also helps to tire the fish.
When connecting mono to the connector swivel on the wire trace, make sure you take the line around the swivel eyes wire twice before tying the knot. The knot should be a non-strangle type knot such as a 5 or 6-turn Grinner knot. When you tighten this, lubricate the mono first, then tighten it slowly making sure it tightens up evenly and neatly. A knot formed like this is ultra-strong for light line fishing and relatively uncomplicated to tie when at sea.
A few other bits of tackle are worth having with you. Make yourself a couple of lanyards from a 4ft length of paracord or climbers cord. Seal the ends with a lighter so they cannot fluff up or unravel. Then tie on to one end a small but very strong stainless steel carabiner clip. Don’t trust an alloy one! The cord can then be tied to the boat safety rail and the clip attached either to the reels harness clips on the reel frame or around the rod above the reel for security should a shark try to drag the rod overboard.
A butt pad is handy for prolonged fights with big sharks as they ease the rod butt pressure on the upper thigh or groin as you play the fish. Make sure when wearing the butt pad that the belt is tight around the waist to fully support the rod. There is no need for harnesses to spread the weight across the shoulders and upper back when fighting blue sharks in the UK, nor belt harnesses.
Some good industrial-type gloves or gauntlets can be handy if, with experience, you get proficient in landing the sharks yourself on deck. It enables you to hold the wire trace with the shark at the side of the boat, and avoids the shark’s skin rubbing on bare arms.
How to build a blue shark rig
The secret to a good shark trace is in the wire that you use. A multi-strand wire, such as 49-strand, is supple and will bend easier, plus kink less. Stiffer wire is prone to kinking and weakening, plus it is harder to work with during construction of the Flemish Loops. It tends to hang straight in the water and reduce the movement of the bait as it’s moved by the balloon.
Berkley 7-strand wire is excellent, plus it comes in a dull brown colour which helps the wire to be less visual in the water. A lot of wire is a bright silver and this can put sharks off in very clear and settled seas, so bear this in mind.
The ideal length for a shark trace is 15-feet. This gives enough length to stop the shark rolling up in the wire and reaching the main reel line. Also when the shark dives for the bottom the wire trace will be alongside the shark’s body, also the 15-foot length guards against abrasion and impact from the tail and protects the main reel line, plus gives the skipper and crew something to grab when the shark comes alongside.
Obviously use the strongest wire you can get away with. 275lb wire is a good all-round choice for general blue shark fishing. It also has the strength to withstand the pointed teeth of a porbeagle should you happen to inadvertently hook one, so use the 275lbs as the go-to wire.
However, in very settled and clear seas, even 275lb wire will see the sharks suspicious and spooky and sometimes only playing with the bait. If this happens, then carry a couple of lighter wire traces made from 175lb wire and try these. Normal blues still can’t cut through the wire, but they can open up the strands so use this as a last resort to get a bite.
Another trick to try in these difficult conditions, is to have a wire biting trace of 6ft in length, crimp a swivel to the end, then Flemish loop 10ft of clear 250lb mono to the wire trace. The clear mono is less visual to the shark and can increase your chances of getting a bite.
Here’s how to build an all wire shark trace. It’s the one we’ve used for over 30-years with no issues.
1 - Take a 15ft 6in length of 49-Strand 200lb wire.
2 - Using a figure of eight crimp, pass one end of the wire through the crimp, then through the eye of a size 4/0 rolling swivel.
3 - Bring the end of the wire back on itself to form a loop, then pass the end of the wire in and out of this loop and again through the eye of the swivel three times. This is called a Flemish Loop and gives the connection strength.
4 - Fully tighten the Flemish Loop as much as you can, then pass the end of the wire back through the same crimp and close the crimp tightly with proper crimping pliers. Do not leave a tag end of wire sticking out of the crimp as this can cut hands when handling a shark at the side of the boat.
5 - At the other end of the trace, using a figure of eight crimp, pass one end of the wire through the crimp, then through the eye of a size 8/0 Mustad O’Shaughnessy 3406 hook.
6 - Bring the end of the wire back on itself to form a loop, then pass the end of the wire in and out of this loop and through the eye of the swivel three times, again tightening the Flemish Loop as much as possible. Pass the end of the wire back through the same crimp and close the crimp tightly with proper crimping pliers.
You can add a rolling swivel in the middle of the wire trace, but this adds a potential weakness and is not really necessary for blues. What we would suggest with all swivels is that you use matt black ones. When you’re playing a shark and there are other sharks in close proximity, the flash of a chrome or silver swivel will see them attack the flash and this causes a cut off where it is knotted to the main reel line and the loss of the shark.
The hook size is plenty big enough at 8/0. Any bigger and you start to have problems sinking the hook at range when using light lines. The only time to consider a 10/0 sized hook is when there is a really good chance of picking up a much bigger fish in the 100lb plus range indicated by other recent captures. Use straight patterns such as the Mustad Sea Demon, not offset point patterns like the Mustad Seamaster. Offset points can be difficult in penetrating the tough jaws of a shark as the line pressure on an offset point is reduced compared to that on a straight point.
Some anglers now use circle hooks which are a commercial long-line hook designed for self-hooking. These have an in-turned point. The design sees the hook turn in the mouth of a fish as it takes the bait and turns away typically hooking the fish in the scissors of the mouth. You do not strike with a circle hook, you just let the line come tight and this hooks the fish. They can work well, but a lot of experienced anglers still avoid them as they can result in a lot of dropped fish.
Whichever hook pattern you choose, keep the hook point sharp at all times. The best way to sharpen a hook is to look at the points profile. J hooks will have flat sides called a knife-edged point and a rounded outside to the point. File the flat sides down evenly and along their full length until the point itself reduces. Don’t try to get the hook over sharp otherwise, the point can bend over when it pulls into the shark’s tough jaw. Circle hooks have round points. These need reducing until the point becomes sharp but not thin.
We’ve also found over the years that sharks, for some reason, are more wary of brand new hooks. Used hooks in perfect condition but with some discolouring of the surface metal, even very light surface corrosion, tend to catch more fish than a shiny hook. Check used hooks for strength, but these would be our first choice when making up traces.
Some anglers use plastic bottles or big corks to suspend the bait and the trace in the water. We have to think about pollution in the sea nowadays and a simple cheap party balloon remains the best option. The cheap rubber material the balloon is made from when lost quickly rots due to UV light and degrades. The way the Talk Sea Fishing team rig them though, they tend to burst during the fight with a shark, but stay attached, so the balloon's remains are not lost and can be disposed of sensibly. Here’s how we do it.
- Take a 6-inch length of supple telephone or coated jewellery wire.
- At one end twist on using neat touching turns of the wire a size 6 swivel. Make sure there are no sharp tag ends.
- Slide the swivel on to the mainline before you tie on the wire trace.
- Above the free sliding balloon swivel, knot the mainline in tight touching turns wind on a 2-inch length of the wire. Again, make sure there are no tag ends standing out and that the coils are straight and neat.
- When ready to fish, blow up a balloon no bigger than the size of a normal large grapefruit and knot the end.
- Twist the free end of the wire connected to the sliding swivel to the tag end of the balloon to secure it in place.
The balloon can slide freely on the mainline and on the short section of wire and swivel it cannot twist around the main reel line during fishing. The coils of wire on the main reel line act as a stop so you can set the depth the bait fishes out as the wire coils can be slightly twisted open as a whole unit and slid up or down the line, then tightened to lock it back in place. Also, because the wire coils are tight and wire flexible, when retrieving line with a shark close to the boat, the wire coils travel easily in and out of the rod rings as a fish takes line. Done properly we’ve found this the very best way of adding a stop.
Some angler half-hitch a match as a stop, but this can kink and weaken the mono. Sliding stop knots do not lock on tight enough to combat the buoyancy of the balloon when a fish initially dives and this can see the balloon stay close to the surface and the shark be 150ft down. Stick to the telephone wire is our advice!
Balloon colours are important regards being visual if you are fishing well away from the boat. Warm colours such as yellow, white and orange are fine when you’re fishing within 60-yards of the boat. If your balloon is further out, and especially when the sea swell is white-topped in windier weather, then choose a cold colour such as black, blue or dark red. These actually stand out better than the warm colours when fishing at range.
You also need to ensure that the bait is kept down in the water. In a fast tide, even with the weight of the wire trace, the bait will lift up and not present right without additional weight. This is achieved by using a length of telephone wire about 6ft above the bait which is coiled tightly around the wire trace and locked off so it can’t come off. Leave a long tag end where it locks off, then twist on a 3oz lead weight by the eye. This is a sacrificial lead that will come off during the fight, but it ensures the bait is kept down in the water and retains its more natural presentation. The lead weight will not visually put the shark off from taking the bait. Only use just enough weight to keep the bait down in the water. The more weight you add, the more the shark will feel that pressure when it takes the bait.
Blue shark fishing baits
The blue shark, as we’ve read earlier, are quite carefree in what they’ll eat, basically taking advantage of anything edible they come across. Mackerel is rightly quoted as the most reliable bait, which it is, but this is because these are normally widely available and in numbers, but there are other baits that work just as well and put you at no disadvantage.
Whole fresh garfish body sections are probably the very best bait of all. The blue shark shares the same upper surface waters with the gars and these form a regular part of the blues summer diet. A body section about 10-inches long is enough. To present a garfish bait, cut off the head and the tail fin. Pass the hook through the tail end at the cut, then pass the point as far down the bait as you can until the bend stops you going any further. Now pull the hook fully through to expose the wire. Then go back in the same as before twice and bring the hook out near the head cut. Basically, you’re stitching the hook in and out of the bait. This presents the body section vertically in the water with the hook well exposed for easy hooking.
Fresh and frozen herring is excellent. It’s a nice oily fish and an added bonus is that when presented in the water the scales will naturally fall off and shower down into the water column. This helps imitate a wounded fish and the blues love a victim.
When baitfish stocks are in short supply, as they can be sometimes nowadays even in high summer, then white fish such as pollack, coalfish, whiting and codling will also work but won’t achieve the results an oily fish will.
One other fish to consider an alternative bait, and it’s one that’s not so obvious, is farmed rainbow trout. These are pellet fed and the flesh can be quite oily. The blue will take these without hesitation, so it’s worth knowing. Trout about a pound or so in weight is the ideal size.
Another bait that can produce well, especially when fished deeper, though at the surface too, is squid. Depending on size, these need to be presented with the hook passed down from the tail end through the whole body and brought out at the head between the tentacles. Bind the body to the hook with a few turns of bait elastic to stop it collapsing down to the bend of the hook in a blob. If the squid are small, then put the first squid on as described, then add another alongside it and use plenty of bait elastic to hold it in shape.
Let’s deal with mackerel bait more fully now. One of the commonest mistakes is to cut the tail off the mackerel, leave the head on but cut out the backbone to make a flapper. The hook is then passed just once through the two jaws. The problem with this bait is that although it partially works, all too often the blue shark will take the bait across the middle of the body and when it feels resistance from the balloon, shut its mouth and cut the fillets off but misses the hook. It’s an effective bait and looks good in the water, as it gives plenty of movement, but it will cost you fish.
Another big mistake is to not cut off the tail fin of the mackerel. This can cause the bait to spin in the tide and creates twist and kinking in the wire.
Some anglers, and even skippers, also present the mackerel bait head facing up to the surface with the hook coming out just below the gill covers. Again, this can see the blue shark take the lower end of the bait and miss the hook completely.
A mortally wounded or dead mackerel will drop down through the water column head first due to gravity. This is how we should present the bait, head down. Begin by cutting the tail fin off the mackerel about 2-inches below the tail. Thread the point of the hook through the open cut in the tail end and push the point down as far as it will go until it can’t go further due to the bend of the hook. Bring the point out of the flesh and pull the hook and the crimp on the wire out of the body. About an inch further down, put the hook into the body and bring it fully through as previously, and then a third time. This should place the final hook exit point for the hook point either just behind or coming through the gill plate on the average-sized mackerel. When the shark takes and runs with the bait, it will turn the bait in its mouth to swallow it head first as this is the easiest way for the shark to swallow. This presentation, with the hook near the head, allows you to strike early and avoids gut hooking any sharks.
What the Talk Sea Fishing team prefer to do when presenting a mackerel bait as described, is to choose a medium-sized mackerel and mount it as above. Before the bait goes over the side, we like to add a single small fillet of mackerel hooked just once through the thin end of the tail and leave this to hang a little way below the hook point. As the balloon bobs up and down in the waves, the fillet will flop up and down and gives an otherwise static looking bait some natural lifelike movement. This little trick can make a massive difference to the number of takes a bait can draw during the day, and it’s especially effective on the calmer days with little swell.
Avoid putting two or three baits on the hook in bunches which is something more akin to targeting massive sharks overseas or in films. This might work for massive porbeagles, tigers and Great White’s but will only result in mostly dropped runs from blue sharks that won’t often go over 100lbs.
Rubby dubby is the common name in the UK for what the Americans and Australians call a chum trail. It is a concoction of various natural ingredients designed to put a scent trail in the water for the sharks to follow to source, this being the boat and ultimately the presented baits. It’s important to realise that rubby dubby is vital to a successful day’s shark fishing. It also needs to be maintained without a break. Once you start, keep the scent trail going.
There are many secret ingredients and “family” recipes associated with rubby dubby, so firstly we need to dispel some untruths. Animal blood such as pigs blood or cow’s blood is again something for the films. In our experience, we’ve seen it used and witnessed it being pretty much useless. If anything it is an alien substance to the blue shark and should be avoided. It’s also disgusting to use. Mixing naturally caught fish and letting the rubby dubby bin stew and ferment in the sun until the smell is unbearable is also less effective than a chum made with fresh ingredients. How often does a blue shark come across three day old fish? It doesn’t! Anything fish like bar whales and seals are eaten up within a day, so get no time to rot. If you want an effective rubby dubby or chum, then use fresh ingredients, ideally those caught on the day and turned into instant dubby.
You really need only three ingredients to make the perfect rubby dubby. Fresh mackerel or herring, animal feed bran and pilchard oil. Some fish processing plants also produce an oil that is eventually used in soaps and cosmetics and if you can get some of this, it’s also excellent. It’s a case of asking at the appropriate factories.
A key thing about rubby dubby is that you want it to first attract the shark into the boat, then excite it enough to eat. What we don’t want to do is feed the shark. Here’s how to make the perfect and most effective dubby.
The best way to prepare mackerel for dubby is to have a mincer onboard. Cast iron hand mincers once used by butchers are cheap, effective and can be found in secondhand columns and sales. If you prefer, there are electrically powered mincers that will cost more but are twice as quick to use. Putting the mackerel through one of these reduces the whole body and bone to a thick paste. If you haven’t got access to a mincer, then put several whole mackerel into a metal or tough plastic bucket, then pummel it with a length of 3in by 3in timber or a 3in diameter metal pipe. This will pound the mackerel into mush. This is perfectly good enough for the dubby, but does not reduce the mackerel as well as a mincer will.
Mix the thick paste with plenty of animal feed bran which is available from pet supplies and farmers stores. Now add in a good amount of pilchard oil. If you can’t get pilchard oil a natural cooking oil such as vegetable oil will do. It’s a case of getting dirty now and with your hands mix the whole lot together until the bran really starts to take on all the oil and the mackerel paste. Try to do this while travelling out to the shark grounds, or at the port before you leave so that the oil can really penetrate and swell up the bran. The consistency should be enough to allow you to form solid balls of the dubby without it breaking up. You want it to wash out slowly, not all at once.
We also like to add chunks of mackerel body section about an inch or two long to this mix. This sees little chunks of mackerel break off in the water and just adds some more bulk to the slick, plus the bits fall down in the water column and entice deeper swimming sharks up in the water to feed.
The traditional way of presenting the rubby dubby over the side is to put it into mesh onion sacks that are tied appropriately to the gunnels. This works fine, but has several distinct disadvantages. Firstly, the bags are messy on deck. Even if you try to keep things contained in a big bucket or fish box, inevitably the mix will get trickled onto the deck as you continually replace the contents and this results in a slippery and dangerous deck. Also, the contents can wash out quite quickly meaning much more work and a lot more dubby being needed. Secondly, and this occurs quite often, a blue will approach the boat and rip the sacks to bits losing both the contents and effectively making a break in the scent trail.
A far better system on charter boats is to have medium-sized plastic buckets with lids and drill holes around the body of the bucket. The holes need be no more than 1cm diameter for paste baits, 1.5cms for dubby with chunks of mackerel mixed in. Some skippers use the 25-gallon screw head barrels the same way.
A minimum of three buckets or barrels of dubby is ideal. The aim is to make the scent trail as wide as possible. To achieve this, put one barrel on the downtide stern corner and one up by the cabin. The third is tied to the middle of the uptide gunnel. Only have the bucket's base about a foot into the water. This causes a constant washing out of the contents as the boat lifts and falls in the swell. The two downtide buckets give you the width of the scent lane, and the middle uptide gunnel bucket helps concentrate the smell in the middle of the scent lane.
When it’s time to refresh the buckets with fresh dubby, do it one at a time to maintain a strong scent in the water. If the sea is calm and the buckets are not lifting and falling with the boat effectively, periodically lift the buckets up and down in the water to wash out more content. This is another way of stimulating sharks to feed that can be seen to be swimming aimlessly around the boat.
When fishing from smaller private boats you need to avoid the mess of the onion bags, equally big buckets can be too cumbersome and space taking on smaller decks. To get around this effectively, a good system is to make dubby containers from 24-inch lengths of 6-inch plastic drain pipe. At one end push in a fixed solid stop end and bolt this securely to the main pipe. Drill around the drain pipes body a series of 2cm holes. Add a push-in stop end. Drill two opposite holes at the top of the pipe but below the depth of the stop end and tie in a small rope loop for attachment. These can be tied to the stern or bow of the boat. If you put the pipes into a bucket of dubby and load them, this minimises any mess on deck, plus the pipe containers take up much less room. This system is also a great way to present smashed up mackerel when you just want blood and bits going into the water. Also, the sharks can’t bite through the pipes, even though they will try.
Understanding how the scent trail works in the water is key to placing your baits at the right depth.
Think of the scent trail as taking on a widening cone shape or the shape of a torch beam as it travels away from the boat. On days when the wind and tide are flowing in the same direction, or when there is minimal tide and no wind, the scent trail will tend to stay more under the boat and travels less distance, but it does go much deeper. On these days, a good presentation of baits would be to have one bait fishing directly off the side of the boat and shallow at 15-feet, the second with a balloon float set 15-yards away from the boat at about 25-feet, the third 30-yards away from the boat at 35-feet and the fourth ballon at 45-yards but with the bait set much deeper at 50-feet. This is a starting presentation, but then take note which depths takes are coming at and go deeper or even shallower for all three baits fishing away from the boat.
The ideal conditions for creating a wide and long rubby dubby trail is wind against tide. This sees the boat held back by the wind as it blows against the structure, but the flowing tide is quicker and this sees the scent trail or torch beam much shallower but travel much further. In these conditions, the presentation needs a different approach. Go for all four baits on balloon floats. Set the first 20-yards from the boat and the bait 20-feet deep. The second balloon is 35-yards out at 30-feet deep, the fourth at 50-yards goes at 40-feet and the fourth is set at 60-feet deep but is run out to 75-yards. Again, be prepared to adjust these depths as fish are caught, or not caught, for changing depths intermittently when you change to a fresh bait is always worth trying if bites are not forthcoming.
The pilchard or vegetable oil will also indicate where the scent trail is running as it will calm the sea's surface. However, this can be confusing. Often the calm surface slick will appear to flow off to one side and the balloons seem to be outside of the slick. This is an optical illusion as the main scent trail and balloons are naturally positioned by the flowing tide. The surface oil though, will veer with the wind and sit off the true direction of the actual scent trail. This is also sometimes induced by certain boat designs sitting off the wind direction at a slight angle to the true flow of the tide.
When the last bucket or barrel is placed, a good thing to do that can help increase the catch, is to cut a couple of whole mackerel up into 1-inch body cubes. Drop these over the side close to the boat one every 20 seconds or so. These will slowly drop through the water column and work much deeper than bits from the scent trail can. These will fetch up any sharks that are working much deeper that would otherwise completely miss the rubby dubby slick
Hooking and playing a blue shark
Always remember when sharking that the start and end of the fishing day can be just as fruitful as the main part of the day. Deciding who goes where and at what distance out from the boat needs to be sorted out before you reach the fishing grounds. Also, as individuals, you should have your tackle ready and baited with the balloon attached and set to the initial start depth. We’ve already seen that sharks follow the sound of boat engines and often you can get a bite as the first bait is dropped in and trotted away from the boat.
Obviously, the furthest and deepest bait goes out first. When you trot a bait away from the boat do this with the rod and reel in your hand and under full control, never just propped up in the safety rail rod holders. Sharks already near the boat that you can’t see will take a bait as it’s travelling away and you need to reel in free spool but with your thumb on the spool to control should an early run occur. Once your bait is set and fishing, then place the rod in the holder with the line ratchet on and the clutch set with just enough pressure to avoid an overrun, but light enough for the shark to take line without feeling undue pressure.
Experienced sharkers like to keep an eye on the water and watch the balloons. You can frequently see small splashes of a shark's tail, or the fin cutting through the surface water as they search out the baits. This gives you a hint what might be about to occur. Also watch for seagulls lifting off the water altogether, a sure sign a shark is cruising below the surface.
When you get a take, the line ratchet will scream and indicate a shark is running with the bait. It takes timing and practice, but let the shark run 10 to 15-yards, then gently ease the drag forward on a lever drag reel, or reengage it on a star drag reel, and click the line ratchet off. The line will draw tight and when you feel the weight of the fish just let the rod bend over into its natural fighting curve and this is enough to set a sharp hook. Never strike wildly. This is a sure way to either cause a snap off or pull the hook out of the mouth of a shark that is still turning the bait. This method of hooking sees sharks lip hooked or hooked in the main jaw.
If, at any time, a shark runs when taking the bait then suddenly stops without warning, then adopt the same sequence, immediately engage the drag, click the ratchet off and tighten into the fish. Again, do not strike. As the fish feels the sudden increase in pressure, it will turn and run setting the hook for you.
When the shark feels the hook, it will run fast. Smaller fish tend to dive but not too deep and fight it out in the top third of the water column. Bigger fish go deep, it’s their natural instinct and this crash-dive is inevitable and proves the need for a carefully set drag that can give line easily, but make the fish work for every yard of line at the same time. After the first dive, they are likely to circle in the water column, then crash-dive again. It’s a simple fight letting the clutch do the work. The angler’s job is to keep the rod bent in its natural curve, but when the fish is not running, lift the rod tip to raise the fish, then drop the rod tip down a couple of feet and regain line on the reel as you do this downward stroke. This fighting tactic is called “pumping” the rod and that is exactly what you’re doing, pumping the fish up using the rod as a lever.
Bigger sharks will come up in the water and crash-dive again several times. A sign they are tiring is when they hang in the water column using all their weight and going round in circles. One last thing to be aware of is that when the shark sees the real daylight they will usually make one last fast crash dive. This can be 30-feet or all the way back down to depth. Sharks are like people and individually built of different characteristics. Some give up easy, some don’t. A good adage in shark fishing is to expect the unexpected at all times!
A definite indicator you, the angler, are fighting a shark far too hard is that they will roll in the trace. This is a natural defensive mechanism for the shark. You can mostly feel this happening through the rod, and more so when the shark spins the other way and the wire trace pings off its tail. If this happens back the drag off slightly and ease up on the direct pressure. When sharks roll in the wire trace they flex their bodies in and out and this will pressure the trace and can seek out any weaknesses, so is best avoided.
Another typical tactic sharks use is to swim alongside the gunnel and go round the bow. Walking a shark around the bow is a common occurrence and we’ve seen sharks go round the boat two or three times, so be prepared for this. Some sharks will also go right under the boat and this means you need to dip the rod tip well down in the water to keep the line well away from the boats hull and more especially the prop, so dip that rod tip deep and if you have the presence of mind, just ease the drag of a fraction to encourage the shark to swim away from the boat, then tighten it up again.
Many anglers think it’s all over when the shark hits the surface. Granted, it’s the job of the skipper and crew to land the shark, but you need to keep aware and be prepared should something go wrong. As soon as the skipper grabs the wire trace, ease the drag off your reel to a point where if the shark thrashes and dive again, line can be given easily without over pressuring the shark. During the landing process, stand back from the working crew, but near enough to have the rod tip still hanging over the water to avoid any chance of the line catching on anything.
What happens to the other anglers baits when a shark is hooked? This is a judgement based on the moment. The shark will dive when hooked and this can keep the line away from the other baits, especially if it’s one of the baits nearest the boat that is taken. Sharks tend to go deep and to the side, so random winding in of the other baits can cause major tangles. The best system is to basically just see what happens and how the shark fights. If it’s obvious a shark wants to fight close to the surface and is making fast runs, then if it’s possible, get the other baits in. If it goes deep just monitor the situation.
The other reason it can be worth leaving the baits out is that sharks often travel in small packs, so a double or triple hook up is on the cards. This may sound like mayhem, but if each angler keeps track of what’s happening and applies side strain to steer the fish away from each other major tangles are very rare in these situations.
How to induce more takes
Like all fishing successful sharking tends to depend on how much effort you, as an individual, are prepared to put in. There are some little tricks and tactics we can use that will induce a bite from a shark that is swimming in the scent trail but unsure whether it wants to feed or not.
A great way to interest a shark, is to periodically wind in your bait slowly retrieving maybe 10-yards of line. Now let the bait rest for 30 seconds, then release line to reposition the bait exactly where it was originally. We keep stressing that sharks like a moving or falling bait and this simple manoeuvre of readjusting the bait gives it natural movement imitating a wounded or dying fish. The sharks tend to hit the bait mostly when it’s being trotted back to its original position, far less common is a hit while the bait is lifting in the water on the retrieve.
Another option on the same theme for the furthest balloon is to trot the bait out further, say up to 25-yards. Leave it for 5 minutes, then retrieve it back again. This is a good tactic to try when the sea is calm and settled. Sometimes, the bigger sharks choose to stay out at range and won’t come into the boat so extending the range of the furthest balloon can sometimes locate them.
Remember to also readjust the depth of all the baits to allow for the increase and decrease in tidal flow. Go deeper when the flow is light and shallower when the flow is faster. You’re trying to keep the baits in the scent trail where the sharks will mainly hunt.
Lifting a dubby barrel, bucket or bag and giving it a good shake will make noise that the sharks home in on, plus it releases a flood of scent and fish bits that will excite the sharks. This can see one of the inside baits closest to the bait taken.
It also pays to have a separate rod prepared but with no balloon on. This can be baited and when a blue shark is seen approaching the boat, which is common, the bait can be dropped into the water and freelined. Don’t throw the bait straight at the shark as this will often frighten them and they’ll disappear. The right approach is to watch the shark, shake the dubby containers to keep it interested, then, when the shark is still swimming close toss the bait into the water well away from the shark, say 20-feet or so. The shark will see the bait dropping in the water and invariably takes it. If it refuses, leave the bait in the water but draw it closer to the dubby buckets and again give them a good shake.
If a shark can be seen a little way from the boat that refuses to come nearer whatever you do, try cutting up small bits of a fresh mackerel fillet and drop these into the water. This can be enough to get it feeding and more likely to come closer to the boat. If it does, then drop the freelined mackerel to it as previously described.
How to handle and photograph blue sharks
The best way to handle sharks is either at the stern if the boat has a marlin door, or at the gunnel. Use a loose noose rope and as the shark is on the surface put the noose on the deck for the angler to step in, slide the noose up and over the anglers head and up and over the rod, then down the line and over the sharks head, then pull it tight. Now lift the shark aboard using the boat and with someone holding the tail and the middle body of the shark. Place it gently on a wet deck and then someone should straddle the shark in front of the dorsal fin with both knees and legs to stop it from writhing around, Remove the hook and get any tagging and measuring process done.
To photograph the fish, you need to fully support the shark’s belly, so someone needs to do this while another holds the tail. Place the shark gently onto an engine cover if possible and photograph the shark with its full weight supported, this being the best way. If there is no engine cover, then hold the shark across your body with your arms wrapped around its full girth. This fully supports the shark and a photo or two can quickly be taken.
Sharks have a resilient nature but should not be kept out of the water for longer than is necessary, then released by sliding them gently into the water. Anyone who doubts the merits of this procedure only need to look at how many sharks have been tagged and released in this way and then recaught in perfect condition, and even on the same day, or months or even years later.
Top tips for blue shark fishing
- If there is any neat mackerel blood left in the fish box or bucket, dilute this with a little seawater and tip this over the side when sharks are swimming in the slick. This is a high stimulus to them and will make them more eager to feed.
- Periodically, a good charter skipper will restart the engines and run them for a few minutes. This will attract sharks that are used to approaching working trawlers as they have learnt that it's easy feeding as fish fall from a hoisted net, or are thrown overboard.
- It also pays to have someone catching and releasing mackerel while shark fishing. The distress vibrations put out by the mackerel as they fight will home the sharks in. Remember to not handle the mackerel when releasing, mackerel can be easily released by holding the hook and with a sharp down motion of the hand, released easily.