by Chris Bartow
What is a blue pike?
Distinguishing blue-colored walleye morphs from traditonal, extinct "blue pike"
Above - A Large 27" Blue Morph Walleye Caught in Lac Dumoine, Quebec, June 2008
Historically, the Blue Pike (Sander Vitreum Glaucum) was a native fish (primarily in Lake Erie) along with a smaller breeding stock in Lake Ontario. It was the most commercially harvested fish in the lakes and drainages for a good part of the last century and a regional favorite as the fish of choice for local friday night fish frys. Indeed, many old timers say the blue pike was actually tastier than their larger cousins, the yellow walleye.
The "Blue Pike" was not a pike at all - but a member of the perch family and very similar in appearance to a traditional yellow walleye or Sauger. The main differences:
- They preferred cooler, deeper water (60-90 feet.)
- Their max size topped out at 20 inches.
- They were black and white/silverish in color with a 'blue' tinged slime coat - particularly evident on the dorsal fin and often on the white underbelly.
- They had larger eyes than yellow walleye or sauger (probably as a result of their deep water foraging preference) and did not have the white tips on the anal and lower caudal fins seen on yellow walleye.
It was listed as extinct in Lake Erie and Ontario and their respective drainages by the mid 1970's - due to unmanaged, commercial overfishing.
But are they really extinct?
Fisherman have been reporting blue walleye catches often since the official extinction of the blue pike in the 70's. Reports, photos, skin samples and entire fish have been documented.
Our fishing group has indeed caught good numbers of these fish on certain trips.
…But what we have caught are not "blue pike" in the traditional sense.
They are yellow walleye color morphs that lack the traditional yellow color, are black and white/silverish with a blue-tinged slime coat… sounds like a blue pike, I know, but consider this:
- The fish we caught had the traditional yellow walleye white tips on the anal and lower caudal fins.
- Some fish caught were over the size limit of the historical blue pike (I caught a 23" one in 2007, for example and you see a 27" fish above.)
- The blue fish we caught were landed at locations that were yielding substantial traditional yellow walleye catches at the same time. They did not have any noticeable larger eye than the yellow fish we caught.
…So these blue fish we caught seemed to be 'blue' color morphs of the traditional yellow walleye species.
These are not 'Blue Pike'…
The larger questions…
- Where did these blue color morphs come from?
- Are they naturally occurring morphs that are now only being adequately documented?
- Are they a morph remnant of possible interbreeding between blue pike and yellow walleye?
- Are blue pike still out there in small numbers in certain Canadian lakes where they may have been planted unofficially by anglers in the last century?
Reports of these blue morph yellow walleyes have come from lakes in the provinces of Ontario and Quebec as well as Minnesota and Wisconsin.
From experience, our fishing group can confirm that these blue morphs occur in large numbers on Lac Dumoine in lower western Quebec. From other angler reports, it appears that the greater Kipawa area and the Kipawa and Dumoine River drainages hold prolific amounts of these blue morphs (Lac Kipawa, Lac Ogascanan, Lac Sassieniega, Lac Watson, Grassy Lake, Lac Dumoine, etc.) In fact, on Dumoine, the outfitter advised that the lake also has 'Silver' morphs… Much like the blues in that they had no yellow skin coloration whatsoever but they also lacked the the blue-tinged slime coat that made their counterparts blue. The outfitter said that the lake held both yellow walleyes and blue morphs in large numbers but some silver morphs also - though in lesser numbers…
There has also been reports of blue morphs caught in many lakes and rivers in Quebec's La Verendrye Park and some fish caught in lakes east of the Park (though frequency tends to drop on the eastern lakes.)
I don't know what the morphological history is on these fish… but they are indeed beautiful.
Fisheries Biologist with the University of Wisconsin, Dr. Wayne Schaefer, has been studying these blue 'morph' walleyes for a number of years and has made some interesting findings - including the following:
DR. WAYNE SCHAEFER
BLUE WALLEYE STUDY UPDATE1
March 1, 2008
1. Two factors contribute to the blue color in walleye:
a. lack of yellow pigment in the skin of the fish.
b. presence of blue pigment in the skin mucous of the fish.
2. We have identified the blue pigment in the mucous as a new protein never before described in the literature. We have named the pigment "Sandercyanin". Sander is the genus name for walleye and cyanin means blue in Greek.
3. Sandercyanin consists of a large lipocalin protein which carries "biliverdin". Biliverdin is a normal excretory product secreted in urine of all vertebrate animals. It forms from the breakdown of "heme", a blood protein.
4. Sandercyanin occurs in the mucous of walleye in many lake and river systems in Ontario, Quebec and Manitoba. It is equally present in both blue and yellow walleye in any given lake or river system.
5. Sandercyanin appears to be moving south across the Canadian-U.S. boarder into upper Minnesota and upper Michigan.
6. Sandercyanin does not harm the health or taste of the fish.
7. Sandercyanin is produced seasonally, with more in summer than winter. It is produced only on the dorsal (upper) part of the fish, above the lateral line.
8. One factor that causes the breakdown of heme to biliverdin is exposure to ultraviolet (UV) radiation from the sun. The earth is normally protected from UV radiation by ozone in the upper atmosphere. In recent years ozone "holes" have been noted over both the north and south poles as a result of CFCs (chlorofluorocarbons) entering the atmosphere. In some species of animals, biliverdin is known to act as a photo-protectant.
9. It is possible that walleye in Canada use, as a sun screen, the very chemical which forms in their blood from exposure to too much sun. This conclusion is still only speculation but it is our best hypothesis.
Below is a presentation developed by the Lower Great Lakes Fishery Resources Office to help anglers identify the elusive Blue Pike - if they still exist…
Presentation Provided by The US Fish & Wildlife Service - Lower Great Lakes Fishery Resources Office