#659. Brine Shrimp

Science, level: Elementary
Posted Mon Oct 5 17:09:27 PDT 1998 by S.J. ().

Brine Shrimp
A warning: Brine shrimp are not completely predictable animals. Occasionally the method described
has not worked--the eggs have not hatched or the newly hatched shrimp have died within a few
days. If you have difficulty, you can involve your students in a search for a method that will work
for your particular set of conditions. The children will gain a sense of the delicacy and complexity of
a living organism and the rather narrow range of conditions under which it can live. (I usually have been
successful in having children keep their jars going for about 2-3 weeks--then they go home)

Materials: vial brine shrimp eggs--pet stores usually carry these, aquarium salt(sea salt is too expensive)
glass jar (brought by children--don't use pickle jars!!! These definitely --no matter how well washed--do
not allow for hatching and growth).

Activities prior to hatching:
1. sprinkle a few eggs on white paper, have students brainstorm a list of what the "brown stuff" might
be. (could use magnifying glasses)
2. record observations: size, color etc.
3. after the children have had a chance to investigate the "brown stuff", you may want to tell them
that they are eggs.--could make a list of possible animals that would hatch from the eggs
4. discuss possible ways to hatch eggs--
5. investigate salt--set up hatcheries ( about 1 tablespoon salt to a cup of water--check egg directions/aquarium
salt directions--things vary with each). Brine shrimp should hatch in varying concentrations of salt (from one
to six percent). Have children use black marker to mark water level on the side of their jar (personal habitat) so
that they can refill it to the same level when the water evaporates.
6. You may want to discuss evaporation--salt remains in jar etc.--only refill with fresh water.
Note: Rapid changes in the salt concetration of the water may kill the brine shrimp. You may need to remind
the students to refill on a regular basis.
7. Add a pinch of eggs to each jar--Sprinle the eggs on to of the salt water--observe changes--this is a long
term observation(will initially float and then they begin to sink--) Keep jars in a warm location--we lost our shrimp
last year --weather turned cold and windy and the windowsill location just got too cold for them.
8. Watch carefully in 3-5 days there should be small shrimp swimming --difficult to see, but they will grow.
9.Food: Feeding is not necessary, if tiny green threads or spots start to grow in the containers. (algae)
If your containers receive enough light algae should grow--Powedered yeast can be added to hatcheries --Too
much yeast will kill shrimp. A general rule is to feed no more than disappears and leaves the water crystal-clear
in 2 days. Once or twice weekly feedings are enough (good point to discuss size of animal and appetite0
10. The brine shrimps gut can be seen more clearly if it is fed colored food. Yeast dyed with food coloring is good
for this purpose.Mix a drop0 of food coloring with a few grains of yeast in a plastic spoon. Mix in a few drops
of salt water from the habitat. Then add a brine shrimp to the spoon. (good luck catching one--hint use an
eyedropper). We observe the gut and swimmerettes by using an overhead microscope--projects the image
to a white screen :)--it's catching the little things that is tricky!!!

This should get you started--if you have any questions -- just ask--if you are willing to sacrafice brine
shrimp, there are many good experiments that can be tried--we usually just raise them for a few weeks and
they meet their end at home.