Sex is a perilous pursuit for the predatory pike

THE countryside is rather quiet at present. Most things seem to be still and dormant, waiting for the spring. But below the surface in our rivers, lakes and canals there is plenty of movement and drama.

The pike spawning season has started.

The pike may be Ireland’s ultimate predator and the slow migration towards their spawning grounds is traumatic for everything that swims. There is a spawning ground every few kilometres in a river or canal and every few hectares in a lake. It’s always in shallow, weedy water — usually between 30cm and a metre deep. Pike eggs are deposited on vegetation, water crowfoot is a favourite but they also use Canadian pondweed, water milfoil or even the dead stumps of reeds or sedges.

The males arrive first, usually around the middle of February. Male pike are all small. Specimens over 4kg in weight are rare. Females, on the other hand, regularly grow up to four or even five times this weight. This is a major contributor to the drama because pike are cannibals — not all pike all of the time but many pike a lot of the time. So there is a real danger a male pike approaching the spawning grounds will end up being eaten by his bride-to-be.

Pike are long, thin fish and they mate by lying along side each other, eye-ball to eye-ball. The theory is that a shorter male is more likely to fertilise the female’s eggs with his milt than a longer one, particularly if there is a current in the water. So evolution has favoured short males and long females.

Over the next couple of weeks the huge females will start drifting in from the deeper water to join the assembled males, who are torn between the desire to mate and the desire not to be eaten by them. Pike are by no means monogamous but their courtship is cautious.

Eventually the deed is done and the fertilised eggs hatch out into young pike, which grow rapidly, feeding mainly on small invertebrates to begin with but changing to small fish after 3 to 4 weeks. A pike can grow to 25cm long in 12 months. But most of them never make it this far because some of the adult pike, mostly the males, hang around on the spawning grounds to feast on their own offspring. It’s a ruthless world down there.

Pike are widespread in Ireland, though there is an argument about whether they are a native fish or an early human introduction. They also occur across the whole of the northern hemisphere but it seems as though some of the largest specimens are found in Ireland — or at least they used to be. They can live for about 20 years but for a female to grow very large in that time span she needs a very nutritious diet. The best nutrition is provided by oily fish such as salmon or trout (also eels, but I’m not sure whether pike eat many eels, perhaps someone can enlighten me on this?). Anyway salmon, large trout and eels have become much scarcer in this country in recent years and pike have had to change to a less nutritious diet which may mean they are no longer able to grow to great weights.

For a long time the Irish rod caught record pike was a fish if 53lbs (24kg) taken by John Garvin in Lough Conn in 1920. It is no longer accepted as the record, partly because it had a 10lb salmon in its gullet and the committee though it unfair that the weight of the salmon was included in the overall weight of the pike.

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