Esox lucius, more commonly known as pike or, in parts of the USA, northern pike (or simply ‘northerns’) is one of the most exciting freshwater fish to catch. It is fast, aggressive and big. But to sustain lengths of up to 1.5 metres* and weights of more than 40lbs, a pike needs to eat a lot of fish.
So how does a big, heavy fish swim fast enough to catch its prey? The answer is in a combination of strategy, mechanics and physiology. Starting with the latter, a pike’s body is extremely streamlined: it is long and thin, with an aerodynamic, pointed face and most of its fins situated towards the rear. This set-up means pike are capable of what are called ‘fast starts’ – sudden, explosive bursts of energy, which enable pike to create massive acceleration and high speeds over short distances.
Looking at the mechanics behind one of these fast starts, it’s possible to see how the pike creates the injection of forward momentum. It coils its body into a compressed ‘S’ formation, then straightens out with a flash of its tail, reaching terminal velocity momentarily. Once the prey is caught, the pike forms its body into a ‘C’ configuration, which slows it down almost as quickly as it started using the resistance of the water.
Then there’s strategy. Pike combine their explosive acceleration with stealth. Most strikes take place from within a metre, so it’s vital for the pike to get close to its prey in the first place. As the animation above shows, the pike starts its attack from close quarters. First, it creeps up slowly on its prey, allowing its steady movements to suggest it poses no threat. Only once it is within the strike zone does it attack, reaching maximum speeds of between 10 and 15mph in the process.**
Of course, pike aren’t the only fish to perform fast starts. Other fish like barracuda and garfish share a similar body shape for the same reason, while many other fish use fast starts to escape life-threatening situations. For a pike, however, it is a method for catching unsuspecting prey from a standing start.
* Note from Wikipedia: “The heaviest specimen known so far was caught in 1983 at an abandoned stone quarry in Germany, where the species is called Hecht. This specimen was 147 cm (58 in) long and weighed 31 kg (68 lb). The longest pike ever recorded and confirmed was 152 cm (60 in) long and weighed 28 kg (62 lb). A pike of 60.5 in (154 cm) was caught and released in May 2004 in Apisko Lake, Manitoba. Historic reports of giant pike, caught in nets in Ireland in the late 19th century, of 41–42 kg (90–93 lb) with a length of 173–175 cm (67–68 in), were researched by Fred Buller and published in The Domesday Book of Mammoth Pike. Neither Britain nor Ireland has managed to produce much in the way of giant pike in the last 50 years, so substantial doubt exists surrounding those earlier claims. Currently, the IGFA recognizes a 25-kg pike caught by Lothar Louis in Lake of Grefeern, Germany, on October 16, 1986, as the all-tackle world-record northern pike.”
** Pike have been recorded at speeds of up to 4.75 metres-per-second in attack and 7 metres per second in escape scenarios. Source: Prey Capture and the Fast-Start Performance of Northern Pike, David G. Harper and Robert W. Blake, 1990.
Video courtesy of Underwater Ireland.