Hi Michal,

The scale you can see on the picture is from a northern pike caught in April (21/04/2016; lenght : 60cm). One important point, that fish lived in oligotrophic waters and possessed technically a slow growth. It means that lenght is maybe not a good indicator to evaluate his age.

Dear David !

In this fragment of scales pike can be seen well five annual rings, as well as the increase in less than a year. Thus we are seeing in terms of age 5+.

Best, Igor

Dear David,

Can you send a full-view of the scale?

All the best,

Adam

Dear David!

I agree with Igor Askeev. Your pike is 5+ years old (on 6th year).

With the best, Oleksandr

Thanks! we also estimate this fish with 5+.

Surprisingly only YOY were introduced in 2013, this individual is probably from the ancestral population, historically recorded on site. Good new!

Unfortunately the scale is too big for a full view, with our camera/microscope equipment.

I also see 5+. 

As we all know, scales are among the least accurate structures for estimating ages of fishes. Studies on Sander vitreus and Perca flavescens alone demonstrate that for derived teleosts age estimates from scales are typically low beginning around the age of maturation. If the authors have the time and resources perhaps a study on age estimation methods for Esox lucius is in order! 

Late to this game, but I also see 5+.

I can easily imagine 5 annuli, though it is poor form to estimate age based on

Precision and Bias in Aging Northern Pike: Comparisons among Four Calcified Structures

Daniel L. Oele , Zachary J. Lawson , Peter B. McIntyre

North American Journal of Fisheries Management

Vol. 35, Iss. 6, 2015

Accuracy of Using Scales and Cleithra for Aging Northern Pike from an Oligotrophic Ontario Lake

Arnold O. Laine , Walter T. Momot , Philip A. Ryan

North American Journal of Fisheries Management

Vol. 11, Iss. 2, 1991

David,

It seems that your Pike has finished five years i.e. currently experiencing 6th year of life. To determine the exact decimal value, you need to find growing season in your study location (in days) and capture day.

More reliable age could have been determined from the whole image though.

Mehdi