Ours go from almost lime green to dark brown. Stress can cause a color change. If my 2 are sitting out in their pool looking so green, They will turn brown if they realize my eyes are on them.Eventually they crawl out of the pool back to their log. If I ignore them they will stay green and stay in the pool. The smaller, shyer one spends more time than the bigger one being brown. Maybe a little intimidated by larger one.What is cute is all 3 frogs in pool, butts facing in almost like a clover leaf!!