Brine Shrimp (Artemia salina)
Brine shrimp are not actually shrimp, but they are crustaceans. They can survive being dried out, set on fire, deprived of oxygen, being boiled, being frozen to near absolute zero, and they can even survive the vacuum of space! They have been revived after being a cyst for over ten THOUSAND years!
Brine shrimp can be found as part the Great Salt Lake ecosystem. Without them, all of the birds that stop there during their migratory path wouldn’t be able to obtain the nourishment they require. The brine shrimp also assist in the cleaning of the lake by ridding the water of contaminants (such as phosphorous, nitrogen, and others that result from household waste). This is exactly why they’re used in laboratories in testing processes to detect various toxicity levels of chemicals.
The brine shrimp itself survives mostly by feeding from various microscopic organisms, such as Dunaliella, a species of green algae. They prefer this particular variety of algae because it’s small, single celled, and has a soft exterior which makes it easier for them to consume, especially as newly hatched shrimp.
Around 600,000 years-old cyst samples have been found in the Great Salt Lake, so that can serve as a hint for how long they’ve been part of its ecosystem.
Curiously, the majority of brine shrimp are females, and it’s them who are able to fertilize their own eggs without the assistance of a male brine shrimp through a process called Parthenogenesis. However, towards the end of fall, males are required to contribute sperm to the egg, and these cysts can remain viable for up to 25 years.
From there, the brine shrimp has a rather simple life cycle: they hatch in the spring from those hard shelled cysts that were laid the previous fall and managed to endure the winter. Afterwards, they grow extremely fast. For example, they have only one eye while they’re in their younger years, but they develop the other one as they progressively grow into adults.
When the conditions aren’t the most favorable for reproduction, they enter anhydrobiosis and reanimate back only when conditions are optimal for the fertilizing process.
Do you remember wanting a Sea Monkey when you were a kid? Those were Brine Shrimp!
Cover image via Flickr.