Why won't anyone reply ?Doesn't anyone know anything about stress stripes?
Durbkat, fish get stressed during transport, no matter how gentle you are with them, and bettas show stress stripes. It is probably an old instinctual coloration to breakup its form to ward off predators or confuse rivals, if they want to make a get away or show submission. Stripes, whether due to stress or a natural coloration (think zebras) break up the outline of the animal, making it more difficult to locate. It's a defense mechanism that is still carried by bettas eventhough our fancy varieties will probably never have to encounter a wild bird or other predator, but if they feel stressed, for example, big giant hand scooping them with a net, they probably feel safer dulling their color to blend with the background. This coloration would probably work great in their rice paddy habitat. Unfortunately, they can't blend to match the neon caves and rainbow gravel of the modern aquarium, so that dull color and stripes is an indication to us that they're not secure about something.
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It's really not that big a deal unless it's prolonged, in which case it could mean unfavorable conditions or disease. If he has colored up already, then probably no harm. Hunding had stress stripes when I introduced him, now he's fine and dandy. Don't worry, just be up on your water changes, feed good food, and he should adjust fine to his new environment. Imagine being jostled around in a bag, scooped up with a net and placed in a new environment. That would stress anything out. I'm not an expert on stress stripes, this is just based on my experience with bettas, and what I can deduce from the behavior of wild animals. Fellow forum members may correct me if I'm way off base, but poor Durbkat hasn't had a response yet, and I didn't want him to feel left out in the cold.