Hi Ramazan. I don't know the species, but have you considered that such differences might be due to latitude or fishing pressure in other localities? When I was working with Centropomus undecimalis, I had the same question as you, i.e. why my data differs from that of other publications? I can send you the article...

Yes, I thought. Von bertalanffy equation showed that male growth faster than female. Their habitat consists of esox lucius, cyprinus carpio, atherina boyerii, squalius cephalus, tinca tinca, capoeta tinca and alburnus orontis. Prey fishes density very low. Analyzes of feeding showed that pike and wels catfish competition for food. Main food item for both pike and wels was tinca tinca.Tench, one of the prey fishes, is much less in the lake than in the others.This situation may be due to the fact that the corresponding length of the age is too high?

thanks, I would like to read your article.

Dear Ramazan,

If you do not feel confident with the results that you have about the potential age (+ 9 years) of a specimen of Silurus glanis of 56.6 mm TL (based on sections of otolith), then I would suggest that you test your result on other structures (e.g., vertebrae) on the same specimen of 56.6 mm TL and compare both age estimations. 

With my best wishes,

Gloria 

Dear Gloria;

Ages estimated from lapilli, asteriscus, vertebrae, section pectoral fin ray and lapillus section. APE, CV and PA were calculated. Results showed that Lapillus section was most reliable bone for Silurus glanis (PA= 76 %, CV=4.6, APE= 3.2).

When lapillus section ages were compared with other bony structures, the highest precision was found between section lapillus and section fin ray age readings. The situation is this. 

Sincerely

Dear Ramazan,

According to your response, you have studied the age of your specimen(s) using different morphological structures and for what I understand from your messages you are concerned that your estimations are higher than those in other publications. You also have studied the feeding habits of the fish and its habitat. Apparently (my interpretation of your messages), you have the doubt that the total length reached by a specimen of ca. 9 years old is high. Why? Such TL is not unusual for Silurus glanis in other places. I have the feeling that you have done a lot of work and that you have compiled many data. Probably, the next step is just clarify what you have and try to publish a paper with the results that you have at the moment, try to interpret them the best that you can, indicating at the same time where doubts remain and why, and postulate some future lines of research concerning this species (and others).  I think that the comments from Hector are very interesting in this context.

Sincerely,

Gloria