SPAWNING HERRING

      Herrings' annual spawning is one of the most spectacular happenings in nature.  Great hordes of those foot-long fish of coastal ocean waters across much of the world annually gather in estuaries, fjords and other back-waters off the oceans in unbelievable spawning spectacles.  Each female herring spawns about 20,000 eggs on kelp, eelgrass and other aquatic vegetation, and other shoreline objects.  The tremendous masses of tiny, sticky eggs adhere to those objects in layers, while vast clouds of milky-white, herring sperm, that cover many acres of shallow-water shorelines, fertilize those eggs. 

     Not all those billions of herring eggs hatch, however.  A variety each of crabs, fish, gulls, sandpipers, plovers and other kinds of marine life, plus black bears and other shoreline creatures, eat many eggs.  Still millions upon millions of herring fry do hatch and form vast schools of themselves along ocean shorelines.

     Several species of herrings inhabit many coastal regions of Earth's oceans.  And all those various related types have similar appearances and life cycles.  Adult individuals of these many kinds are ten to fifteen inches long, and stream-lined, which helps them navigate ocean currents.  Some species are dark-blue on top with silvery sides, while others are olive above and silver on their flanks.  Those colors camouflage herring species from above and below. 

     The various herring species feed and spawn in vast schools in shallow coastal waters.  They are abundant in much of the shorelines of the oceans, where they are preyed on by several kinds of predators.  Their great concentrations attract several kinds of marine predators, including larger fish, bottle-nosed and other kinds of dolphins, orcas, hump-backed whales, various kinds of seals and seabirds, and bald eagles.  Obviously, they are another ocean food basket.  

     Every winter, millions of herrings enter Norwegian fjords.  Those fjords remain open all winter because of the warming affect of the Gulf Stream coming northeast from the Caribbean.  A thousand orcas and scores of hump-backed whales follow the herring into those deep channels between mountains to spend the winter eating those small fish.  Orcas work as a team to corral herring into tight gatherings where those large dolphins slap the schools of herring with their large tails to stun them, making them easy to ingest.    

     Young herrings ingest small crustaceans and mollusk larvae.  Adult herrings consume krill, which is a kind of shrimp, and small fish.                        

     Herrings are a food basket of the ocean coastlines, feeding countless predators.  And those small fish have interesting life cycles in themselves, including their spawning in massive gatherings along ocean shores.  This fish species is another great miracle of nature.  

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