The damselfish Chromis chromis is typically the most abundant fish species in the rocky littoral environment of the Mediterranean Sea, where it feeds in huge shoals on incoming zooplankton and rests near the seabed each night. This species has a fundamental role by transferring carbon, nitrogen and phosphorous directly from the pelagic system to the littoral, additionally it represents a major prey for predatory fish and seabirds. It predates itself on zooplankton populations and is a major consumer of fish eggs, therefore influencing the dynamics of other fish species.

This is a review paper that collates the existing scientific knowledge on C. chromis and discusses on its role in Mediterranean littoral ecosystems.

 The author contends that C. chromis represents a key species in the Mediterranean Sea rocky littoral. It is stated that species is of only minor importance to commercial fisheries, but trends in its population abundance can be indicative of levels of fishing pressure on other commercial species. In fact, the paper shows that where predator numbers are able to recover from intensive fishing (e.g. in MPAs), this is often mirrored by lower intensities of C. chromis.

The author concludes that C. chromis is a possible indicator species for human disturbance, being sensitive to a number of anthropogenic pressures (e.g. fishing, water quality, noise pollution).

Pinnegar JK (2018) Why the damselfish Chromis chromis is a key species in the Mediterranean rocky littoral – a quantitative perspective. Journal of Fish Biology 92:851-872