Damselfish

Damselfishes comprise the family Pomacentridae except those of the genera Amphiprion and Premnas, which are the anemonefishes. They can grow up to 14 inches (36 cm) long. While most are marine, a few species inhabit the lower stretches of rivers in fresh water. Damselfish usually have bright colors.

Many species live in tropical coral reefs, and many of those are kept as marine aquarium pets. Their diets include small crustaceans, plankton, and algae. However, many also live in temperate climates, such as the large orange Garibaldi, which inhabits the coast of southern California and the Pacific Mexican coast.

The domino damselfish D. albisella spends the majority (greater than 85%) of its daytime hours foraging. Larger individuals typically forage higher in a water column than do smaller ones. Damselfish of all sizes feed primarily on caridea and copepods. Males have relatively smaller stomach sizes during spawning season compared to females due to the allocation of resources for courtship and the guarding of nests. When current speeds are low, the damselfish forages higher in a water column where the flux of plankton is greater and they have a larger food source. As current speeds increase, it forages closer to the bottom of the column. Feeding rates tend to be higher when currents are faster. Smaller fishes forage closer to their substrates than do larger ones, possibly in response to predation pressures.

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