Northern Pike Growth Rate & Length To Weight

As northern pike anglers, we are always looking for that next trophy. In searching for my own trophy I asked myself how fast do northern pike grow? Knowing the growth rate will help you analyze your fisheries potential and also provide a better understanding of large fish holding locations.

So, how much do northern pike grow in a year? The northern pike growth rate is accelerated for the first two years of their life with fish seeing size increases of up to 10” per year. After this period the growth rate slows significantly.

This fast growth allows the fish to reach sexual maturity faster and ensure their population thrives. Males will mature more quickly than females and mature at a smaller size. Males will grow 16 to 18 inches within one to two years while females will be 20 to 22 inches in a two to three year time period.

Northern Pike Growth Rate

The growth rate of northern pike decreases after year three of the fish’s life. They are taking the next four years to grow a mere 12 inches from 25 to 37 inches. One thing to note about the growth rate of northern pike is their girth in relation to length. During the first years of exponential growth in length, most fish are rather skinny. As these fish age and the growth in length slows, you will notice a more significant increase in their overall size and weight.

World Record Northern Pike (World’s Largest Pike)

The Largest Northern Pike recorded was caught in 1986 by Lothar Louis on Greffern lake in West Germany. It took nearly 40 minutes for Lothar to bring in a 55 lb 1 oz fish. The previous world record and still North American record was caught in 1940 on Great Sacandaga Lake in New York by angler Peter Dubuc. The world record Northern Pike length measured 52.5” long and tipped the scales at 46 lbs 2 oz.

Norther Pike Length To Weight

Slough Shark, Hammer Handle, Pike, Water Devil, whatever name you call it by, it is the #1 freshwater trophy fish. Just the name brings up images of monsters, now imagine catching these regularly.

Most anglers either do not carry a scale or have an old spring style fish Scale. Some have a more reliable and accurate digital fish scale. The only thing wrong with these is that you can damage a big fish by weighing them this way. Not only does it puncture the bottom jaw, wreck gills as you insert scale tip or cause a broken spine (behind the head) to the neck but they are usually not very accurate. There are a couple of easier ways to find weight without damaging the fish.

Pike Weight By Length And Girth

However, this requires knowing the fish’s length and possibly girth. Do you have a ruler or fabric Tape Measure in your tackle box? NO! The wife noticed me sneaking her sewing tape measure and made me put it back. I forgot mine at home in the other box! HEY! You can still get the length and girth. Got a spare spool of line in your box? NO! Then cut the lure off your line and use some of that fishing line. Cut one piece of the line by placing on the tip of tail and measuring to the tip of the snout (length). Cut the second piece of the line by taking and just snuggly winding the line around the biggest part of the fish belly (girth). Make a loose loop in girth string, (so you can get loop out), and put both in your pants pocket. When you get home, measure each piece of line and calculate or find the weight.

Pike size chart

InchescmWEIGHT (Pounds)AGE
10250.21
13280.52
19481.43
22541.94
24612.35
26662.76
27683.17
28713.48
29.5753.79
3178410
32805.211
32.5826.312
33847.613
34871014
358810.515
36901116
379312.517
38981518
39991819
401012120
41.51052321
431092522
44.51132823
461173124
46.711832.525
471193426
47.512035.527
481223728
48.512338.529
491244030
49.5+124+40+30+

How To Tell Pike Weight By It’s Jaw Size

The northern pike is a predatory fish that lives in North America and Eurasia. It has a long snout that looks similar to a duck’s bill. Pike is a large, heavy fish and the usual method of weighing using a hook through the jaw can cause it harm. An alternative measurement for the catch-and-release angler is to estimate the weight of the northern pike using jaw size.

What you’ll need:

  • Measuring tape
  • Calculator
  • Pike size chart (above)

Step 1

Measure the “gape size” of the pike. Gently open the mouth of the fish and measure the diameter of the jaw from mouth corner to mouth corner. According to P. Nilsson in his 2000 article in the journal “Oikos,” gape size is a linear function of pike body length. As an example, assume this measurement was three inches.

Step 2

Convert the jaw size into millimeters. The formula derived by Nilsson assumes a gape size measurement in millimeters rather than inches. To convert, multiply the gape size by 25.4. For our example this would result in 3×25.4=76.2 millimeters.

Step 3

Calculate the estimated total body length of the pike. Nilsson found that the relationship between the northern pike’s total body length (TL) and gape or jaw size (G) was: TL = (G + 0.339)/0.098. In our example, the total body length would be (76mm+0.339)/0.098 or 779 millimeters. At this point we can convert the length back into inches by dividing by 25.4, giving us a total body length of almost 31 inches.

Step 4

Find the estimated weight of the pike on the “Northern Pike Size Chart” found in References. For the example pike, a jaw size of 3 inches would belong to a pike that weighed about four pounds.

Tips & Warnings

For a rough but faster estimate of total body length, multiply the gape size by 10. The larger the pike, however, the less accurate this method.

How Long Do Northern Pike Live?

In the wild northern pike have a typical lifespan of 7 years. This will put the 37-inch class fish near the end of the species normal life. With that said many Northern Pike surpassing this size are caught. In the wild fish have been aged as old as 25 years and in captivity to 75 years.

It is also important to point out that the female northern pike survive longer than the males. By design, this helps the species as a whole from a reproductive standpoint, but it also means the most abundant fish we catch are going to be female. It is crucial to handle these fish with care since they are the breeding stock for the next year’s class.

Use The Knowledge To Increase Your Catch

Knowing the life stages of northern pike will help you as an angler to find larger fish on your local body of water. The first stages of life as an egg and sac fry are not of great importance from an angling standpoint. After about one month northern pike will be approximately the size of a finger, hence the term fingerling. This is a period of time where their first teeth are growing, and they start to become the predators we know them to be. The first year of life for most pike is spent in the warm marshy backwater where pike will need to eat 5-6 pounds of food for every pound of body weight gained.

Juvenile Life and Spawning

After the first year when the northern pike is between 10 and 12 inches long, it requires larger food sources and more lukewarm water — pushing the fish into the lake where its larger counterparts and other new predators live. It is an important and vulnerable stage of the fish’s life. If it can survive its first year in this new environment, it will be near sexual maturity and ready to return to the marshy backwaters it was born in. In the spring when spawning season occurs northern pike spawn and lay eggs that attach to vegetation.

Finding Larger Fish

This is vital information for us anglers — depending on the time of year, we will be fishing different waters for large pike. In the spring when spawning season occurs some of the largest fish may be taken in the shallow ponds and backwaters. Depending on water clarity you can sometimes see large fish staging in areas pre and post spawn. This is an excellent time to use larger baits that mimic smaller mature northern pike. The males will enter spawning territory before the females looking to stake the claim on prime habitat. By using large baits, you will often entice territorial responses from the largest males awaiting their female spawning partners.

Post spawn some of the best angling waters for large pike will be the areas used for travel from the colder deep waters of the lake to the marsh. The channels and rivers are often smaller than the lakes. This concentrates fish population and makes the northern pike much easier to target even from the shore. Often this can be some of the best fishing had throughout the year making for exciting days on the water and big fish in your net.

Northern Pike Growth Rates To Find The Best Water

Using your knowledge of the northern pikes’ growth rate and life stages plays a vital role in judging a body of waters potential to hold large fish. The first thing to look for is appropriate spawning habitat connected to the lake. Keep in mind this does not have to be extremely close as this fish will travel reasonably far distances if the interconnecting waterways allow. If you find what seems to be an excellent marshy spawning ground the next step is to analyze other life in the area. Keep in mind that smaller northern pike require 5-6 pounds of food to gain each pound. The abundance of baitfish, frogs, and insects are all positive signs of a productive area and a healthy ecosystem.

With excellent spawning habitat located look at the lakes depth, water temperature, and structure. Northern pike will be most comfortable in shallow lakes that remain cool. Coldwater rivers entering the lake or springs are perfect for creating favorable conditions. You also need to look at how much and what type of cover is available. As ambush predators, adult northern pike will use weed beds, logs, and rock piles separately and in conjunction to feed.

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