Herrings feed mainly on small oceanic shrimps or copepods and can filter-feed if there are sufficient densities of its prey to allow this. Individuals reach maturity between the ages of three and nine years. At any month of the year, one of the many populations scattered across its vast range will be spawning. The eggs are sticky and are laid on marine vegetation or the seabed. Fish in the North Sea spawn between January and April at a depth of no more than 70 metres and a sea temperature of 4 - 7 °C.