Tackle and Tactics
I've had a soft spot for flatties ever since I used to catch them as a kid. A recent email asking me about the ability of these fish to change colour (they make chameleons look slow) got me digging about in my box file of 'flatty papers'. I came across several interesting facts that I thought might be worth a mention on the web, so here they are.
The first thing I found was an old study from the 1960s by a dutch scientist called de Groot. He was interested in the way that different types of flatfish are adapted to catching and eating different prey. He started off by examining the guts and the gill rakers of a whole range of species. Turbot and brill which eat large prey such as sandeels and other fish have big mouths with sharp, inwardly curving teeth and strongly toothed gill rakers to prevent escape of the wriggling victims. Fish is fairly easy to digest so their guts are short and pretty simple.
Flounder, dab and plaice all have similar guts (a bit more complicated than the out and out fish eaters) because they all tend to feed on the same sort of animals (worms, shrimps and cockles) but notice that the slightly more predatory flounder has stronger teeth on the gill rakers. The flounder and dab have blunt, conical teeth in the mouth adapted to the capture of shrimps and other crustaceans while the plaice has chisel like teeth in the 'lower' (blind side) jaw that it uses for biting bits off the siphons of clams and cockles. Whereas flounders have conical, all purpose throat teeth plaice have crushing molars that seem tailor made for breaking up the shells of molluscs.
The 'twisted', undershot mouth of the sole is clearly adapted for sucking in worms. Its gill rakers are almost smooth and the gut is a long and winding tube.
All this complicated anatomical stuff tells us quite a bit about the probable 'best baits' to use for these species. Studies on sense organs and behaviour can add to this. As you might expect turbot and brill feed largely by sight and are active only in the hours of daylight. Plaice, flounder and dab are also daytime feeders using their eyes to guide them to prey. However, all three have a well developed sense of smell/taste and in the presence of 'prey-scent' will search for it more actively than if there is no 'smell' in the water. The sole is an out and out lover of darkness with extremely well developed scent/taste systems and also a very touch-sensitive underside - both useful for finding food in the dark or in coloured water..
Finally to return to turbot. Smaller turbot eat a lot of shrimps and these were the food offered in tests carried out by scientists Holmes and Gibson. The shrimps used were about a quarter of the length of the fish. The 'prey' were placed on the end of little thin glass rods and presented to the turbot either moving or still, live or dead. The shrimps could be moved smoothly or jerked. The responses of the turbot to the different 'bait presentations' were scored - 0 for totally ignored up to 5 for a full out attack on the bait. It is believed that turbot like their prey to be about eight times (5-10 times) as long as deep and to be moving. It was noticed that turbot showed interest when the sand was disturbed so this was another factor in the study. Motionless shrimps or blank glass tubes were of no interest at all to the fish. Moving dead shrimps and sand disturbed by a glass rod certainly had an appeal the turbot but MOVING LIVE SHRIMPS WERE BY FAR AND AWAY THE BEST..
In the other experiments it was found that the kicking legs of a living shrimp were an additional attraction. Long thin prey animals were also of importance. Attempts to make an artificial shrimp were worthwhile but fiddling about to produce an 'exact imitation' of a shrimp (with eyes, head, tail and a countershaded body), although slightly better than poorer copies, was really a waste of time.
"So, to sum up, if your after turbot it will pay you to use long, thin 'sandeel shaped' baits. It will also pay you to keep them on the move and possibly even to add imitation moving appendages (a muppet or a bit of bucktail??) but don't bother trying to make it look like a real fish (or in this case shrimp).".
If you have any comments or questions about fish, methods, tactics or 'what have you.'get in touch with me by sending an E-MAIL to - email@example.com
Flatty guts and gill rakers.
Moving bait experiment