Northern pike are one of the most popular sport fish sought by Vermont resident anglers in the open water and ice fishing seasons. To allow us to improve the statewide management of this popular fishery, the Vermont Fish & Wildlife Department is beginning to collect biological data from northern pike and we would like your help.

Biological information such as age, length, size at maturity, growth rate, growth potential, and mortality rate are essential for the management of a fishery. With these data, fisheries managers can evaluate the health and status of a population and make decisions regarding fishing pressure and harvest. However, to collect these data, fish sometimes need to be killed. This is necessary, for example, when removing the cleithral bone that allows biologists to accurately determine the age of a northern pike.

The cleithral bone is the major bony component of the pectoral girdle of the pike. When properly removed, prepared and examined, biologists can determine the age and growth history of a pike by analyzing rings present on the cleithrum and comparing them to the length of the fish. Cleithrum analysis is the only known valid method for determining the age of older and larger pike.

Anglers who harvest northern pike offer an untapped resource of biological samples and information. Collecting data from angler-harvested fish allows the fish to be used for both eating and for data collection.

The Department is requesting the help of those anglers that commonly target and harvest northern pike. In return for supplying samples and information, contributors will be offered an age interpretation of their fish. In this way, not only is a valuable database of biological information developed to help maintain and improve pike fishing, but relationships between anglers and biologists can be developed.

Anyone can participate by following the instructions included here for removing the cleithrum, recording biological information, and submitting samples. Information from any sized pike is welcomed, especially from larger individuals which are often more difficult to sample through normal fisheries surveys.

Thank you for your time and interest in the management of Vermont's fisheries !!

(click on image for a larger view)

Hold dead pike facing left	Lift up gill cover with one hand, exposing cleithrum just behind gills.	Push your thumb between the edge of the cleithrum and the connective tissue and muscle
Move thumb toward the top, and then toward the bottom, to separate most of the bone from the soft tissue.	Holding the top tip of the cleithrum, pull it out and away from the body and slightly towards the head of the fish.	Be sure not to break the tip of the cleithrum under the jaw. Use a knife to finish separation if necessary.
A complete cleithrum removed from the pike.	Using a pencil, fill out a sample form with all pertinent catch information and biological data.	Enclose each cleithrum and tag in a baggie. Please ensure only one tag and the matching cleithrum are stored per bag. Keep in freezer
A cleaned and dried northern pike cleithrum demonstrating 9 annual growth increments.

1. Use the collection tag available for downloading at the bottom of this page, if possible. If you can't print them, or run out, any scrap of paper will do, provided you record all the information as shown in the sample collection tag to the right.
2. Information on the collection tag should be in pencil to avoid smearing and smudges.
3. Record date the fish was harvested.
4. Being as specific as possible, record where the fish was caught. Write the name of the waterbody. For larger lakes like Lake Champlain or Lake Memphramagog, include more specific location information such as the name of the bay or closest point you are fishing in or near. Include GPS coordinates if you have them.
5. Using a tape measure or other measuring device, record the total length as per the illustration to the right. Measure from the tip of the snout to the tip of the upper lobe of the tail when it is bent downwards and straight. Record the length in millimeters if possible, or to the nearest 1/8-inch.

6. If you have an accurate spring or digital weigh scale, record the weight of the fish in pounds and ounces, or kilograms and grams.
7. Remove the cleithrum of the pike, as per the instructions HERE .
8. Place cleithrum and collection tag together in a small baggie. It is important that each cleithrum can be matched to the correct tag. Samples collected through the season can be kept in the freezer and submitted all at once, if you prefer.
   
   
9. Northern pike samples collected from Northeastern Vermont (the Kingdom) should be mailed to Jud Kratzer, Fisheries Biologist for the St. Johnsbury District. Northern pike samples collected from anywhere else in the state, including Lake Champlain, should be mailed to Shawn Good, Rutland District Fisheries Biologist. Addresses are indicated below. Please contact Shawn Good shawn.good@state.vt.us or Jud Kratzer jud.kratzer@state.vt.us if you have any questions about this program.
   
   

   Northeast Kingdom Samples - Contact Jud Kratzer Vermont Fish & Wildlife Department 1229 Portland St. Suite 201 St. Johnsbury, VT 05819 802-751-0100 Download Biological Tags -Northeast Kingdom

   Statewide Samples - Contact Shawn Good Vermont Fish & Wildlife Department 271 North Main St., Suite 215 Rutland, VT 05701 802-786-0400 Download Biological Tags - Statewide