Michigan Aquatic Pest Control Practice Exam 2026 - Free Aquatic Pest Control Practice Questions and Study Guide

Determining the age of a catfish by counting annuli on their scales is not accurate. While some fish species have scales with visible growth rings (annuli) that can be used to estimate age, catfish do not. Catfish have a different anatomical structure called "otoliths," which are calcified structures located in their inner ear. These otoliths accumulate layers over time, similar to tree rings, providing a more reliable means of age estimation.

Additionally, the scales of catfish do not consistently reflect growth patterns due to factors such as environmental conditions and growth rates, which can vary widely. Consequently, using scales to determine age can lead to misleading results.

In summary, the statement is false because catfish age is best assessed through otolith analysis rather than scale annuli. This distinction is crucial for effective fish management and understanding fish biology.