The fertilized eggs take between 10 to 14 days to hatch and the tiny (5.5-7.5 mm) larvae drift with the coastal currents. After another 10 to 14 days, when the larvae (now about 10 mm in length) use up their yolk sac, they begin to feed on phytoplankton and the smallest zooplankton, such as the larvae of barnacles. The herring larvae remain in near shore waters close to their spawning grounds in the protective cover of shallow water habitats.

Usually the older herring have left the spawning grounds by the time the eggs hatch. Sometimes, when spawning is drawn out over a long time or there is a second wave of spawning on the same spawning ground, adult herring might feed on herring larvae.

Herring larvae

Herring larvae. Photo: Western Fisheries Research Center  

Herring larvaHerring larvae. Photo: Uwe Kils/Wikipedia


Monday, October 7, 2013