Subject: krill

Courtney Stirling Casey (stirling@gsosun1.gso.uri.edu)
Sun, 26 Oct 1997 19:40:22 -0500 (EST)

 > What would happen if the krill dies ?
                                                    Francesca Feast  (age 10)
Francesca,
	That is a great question!  In order to answer it I must tell you a
bit about the food chain in the ocean.  Every animal, plant and nutrient
in the ocean is dependent upon every other animal, plant and nutrient -
either directly or indirectly.  Think about the food chain in the ocean as
an upside down triangle.  At the bottom, the pointy end, are tiny plants
called phytoplankton which rely on the sun and nutrients (like you get
from your vitamins and food) for life.  The next step up that
triangle is zooplankton.  These are small animals which feed solely on
phytoplankton.  Krill are one type of zooplankton.  So you can think about
them as one step up the food chain from phytoplankton.  
	Many whale and fish species feed on krill.  In fact the blue whale
feeds only on krill!  Other whales like fin, minke and humpback eat krill
also, but feed on small fish as well.  So, if something happened to the
krill many whale species would need to find another food to supplement
their diets.  In addition, all of the fish that eat krill would have to
search for a new food source also.  Removing krill from the food chain
would have a large impact on all animals in the ocean that either ate
krill or fed on animals that ate krill.  Let me know if you would like
more information.  You could also head to your school library and look up
books dealing with food webs in the oceans.  Good luck.

Courtney

Courtney Stirling Casey
Faculty Research Assistant
University of Maryland
stirling@gsosun1.gso.uri.edu