The brine shrimp (Artemia salina) are very important organisms in the Great Salt Lake ecosystem.  What makes them so

important? Without them, all of the birds that use the Great Salt Lake as a stop along their migratory path would be unable

to obtain the nourishment required for their long and strenuous trip.  Some prominent birds that use the Great Salt Lake are the Eared Grebe and Wilson's Phalarope.  The brine shrimp have many other significant roles in the Great Salt Lake besides being food for the birds.  They assist in the clean up of the lake by ridding the waters of

contaminants such as phosphorous, nitrogen and other household waste products.  These small organisms have a complex

lifestyle and are one of the few organisms that can survive in the brackish waters of the Great Salt Lake. 

    Brine shrimp are quite prolific in the Great Salt Lake.  They survive by eating the various microscopic organisms that live

in the lake.  Brine shrimp are always in constant motion because they are filter feeders and use their appendages to funnel

nutrients towards their mouths.  They generally consume a species of green algae called Dunaliella.  This variety of

algae is preferred because they are small, single celled and have a soft exterior which makes them easier to consume for

the newly hatched shrimp.  When there is too little or too much salt in the lake, the Dunaliella become scarce and the brine

shrimp must eat the larger cells of the diatoms, golden brown algae, instead.  These are not the preferred food source due

to their rigid cell wall of silica which makes them much more difficult to consume and digest, except for the older and larger

brine shrimp.  The green and golden brown algae are too large for juvenile brine shrimp to ingest, so they have found yet

another food source.  According to research done by the Great Salt Lake Ecosystem Project, when there is an drastic

increase in the number of diatoms in the lake, the number of brine shrimp reaching maturity is adversely effected.  This has

been linked to the fact that the diatoms in the lake were larger then the oral cavity of the shrimps thus they were unable to   can be totally dessicated and over wintered in a dormant state.  These cysts float to the surface and form red brown streaks.

that cover an enormous area of the lake during the fall and winter.  They will stay like that until the lake has warmed

sufficiently during the spring and they  will hatch once again.

    The brine shrimp have a simple life cycle that is very well suited for the environment that they live in. They are one of the

few multicellular organisms that have flourished in the Great Salt Lake.  The baby brine shrimp hatch in the spring from hard
 

shelled egg like  spheres called cysts.   These cysts were laid the  previous fall   and remained viable throughout the   winter.  Cysts are essential to the   repopulation of the lake after the harsh   winter.  After hatching from  the cysts,   the shrimp grow extremely fast. As   juveniles  they possess  only one eye,   but as adults they develop two eyes.  The majorityof brine shrimp are females. This is important   because the females are able to fertilize   their own eggs without the assistance   of  the male brine shrimp [Figure 2].   This method of reproduction is called

cysts requires sexual reproduction which means that males need to contribute sperm to the egg.  This special adaption

allows the brine shrimp to flourish in the Great Salt Lake and maintains genetic variability.
 

The State of Utah Department Of Natural Resources http://www.nr.state.ut.us/ October 14, 1998

Brine Shrimp and Ecology of Great Salt Lake Friday May 29, 1998 http://wwwdutslc.wr.usgs.gov/shrimp/

Brine Shrimp Update http://www.nr.state.ut.us/dwr/bsupdt.htm August 18, 1998