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[Out4trout]

....MNR cuts the left front ventral fin on the stocked lakers so that they can be identified between them and the native species....

One slight correction....
The fin clipping is one of several fins, with the fin clipped indicating the year the trout was stocked. The cycle repeats after 5 years. I keep records of each stocked laker caught, and by using the Fin Clip Schedule, know the age to weight / length.

Specifically, the fin clipping schedule for Ontario MNR for Inland Trout is as follows:
YEAR FIN CLIPPED
1998 Adipose
1999 Left Ventral
2000 Left Pectoral
2001 Right Pectoral
2002 Right Ventral
2003 Adipose
2004 Left Ventral
2005 Left Pectoral
2006 Right Pectoral
2007 Right Ventral
2008 Adipose

Year is year stocked, fish are approx 1 year old when stocked.
In the picture, the fin that is clipped is the Right Pectoral. So that fish would have been stocked in one of the following years. 1996, 2001, or 2006. Based on the picture, the fish appears around 5 lbs, which would place it as being stocked in 2001, born in 2000.

Cheers

[RJ]

Now that is some fantastic information!

[troutnmuskiehunter]

That's some awesome info....thanks..I guess RJ and I learned something new today

[Out4trout]

No problem - it took me a while to locate the official fin clipping schedule info, I'm glad I could make it more easily accessible for others who share the interest!!!

One thing I have found is that the adipose fin clip is easily overlooked, though usually the stockers are not as dark as naturals.

I have made a calculator (nomogram) that estimates lake trout age and weight based on length and girth. It also works in reverse, for example, entering the weight / length will compute girth and estimated age.

With a data set of approx 80 points from stocked lakers caught since I started recording the data, I compare each estimated age to the fin clip schedule and it seems to be fairly accurate for lower latitude lake trout. Trout from higher latitude lakes (>50N) have entirely different growth rates.

I'll finesse it into an executable application one of these days and make it available to others. More of a winter project, free time in the summer is spent on the lake... chasing that elusive 20lb laker that I'm sure is there...

[Wall-I-Guy]

Thanks Guys.....Rob, have you started your vacation up at the cottage yet??

When I wake from working all night around noon Monday, I head to the cottage. Likely meet you out there at some point.

[Mike P]

Thanks for feedback guys & thanks Out4trout for info.

[BC MOM]

Hi Mike, what great pictures. Your Dad & I were very impressed. Nice to see you are doing what you have always had a great passion for. Your Dad will be fishing in Nootka Sound soon. Hopefully he will catch some fish as nice as yours. Now, did you eat the fish????

Mom in Victoria, B.C.

[Mike P]

I don't know how I missed this...but my MOM is a fellow fish-hawker!