May 2026

Worldwide, the oceans’ coral reefs harbor about 1,500 species of fish, including some with adaptable sexual identities.

Wrasses, parrotfish, and other reef fish start out female and eventually become male. However, other types of reef fish change sex according to the needs of the group. If there aren’t enough males or females, the problem is easily taken care of. Gobies that live in Japan’s coral reefs can change back and forth as need dictates. If the dominant male dies or leaves, a female will become male, changing gender in about four days. If a larger male shows up, the gobie that changed simply switches back to female.

Many fish that change sex do so quickly. A particular variety of sea bass found in reefs from North Carolina to Florida and in the northern Gulf of Mexico are both female when they meet for mating. One switches to male, they mate, then both change sex and they mate again. This toggling between sexes is accomplished by color changes; the female is blue, and the male is orange with a white stripe.

Borrowed by Daheap from The Book of Incredible Information; Publications International, Ltd.