Salinity Critter cards
On the back of each card, write what
makes each critter significant to the
study of SALINITY
Where do these organisms live on the
Gradient of Salinity?
TOTALLY FRESH
BRACKISH
OCEANIC
SUPER SALINE
Elodea
Elodea is a freshwater flowering plant
(not an algae) that typifies a botanical
adaptation to an aquatic lifestyle. As a
result, it is not tolerant to salt water.
Useful for classroom lab demos:
microscopy
plasmolysis
photosynthesis
Surf Grass
(at low tide)
At hide tide
Surf grass is a flowering marine plant,
and so is tolerant to salt water.
It lives in the intertidal zone, down to
40 feet deep
You also have seen Salt Grass
(on the Gradient of Salinity)
Seaweed
Three
types
One of three divisions of
multicellular algae:
green
brown
red
These are mostly marine, and are
customarily called “seaweeds.”
They can survive almost complete
dehydration during low tides.
Dryin’
but not
dyin’
Caspian Sea seal
By the way, just where is the Caspian Sea?
The
largest
landlocked
sea,
about
one
third as
salty as
the
ocean
Brine shrimp
Little crustaceans that are tolerant of
extreme salty environments,
from 24‰ – 250‰ !!!
(although the optimal, as you know by
now, is 60‰ – 100‰ )
Mono Lake
San Francisco Bay
Fiddler crab
Crustacean that burrows in muddy
ecosystems, like brackish water
estuaries
Three-spine stickleback
Example of a euryhaline fish. Many
species live in brackish water
(like estuaries in Washington.)
Tidepool sculpin
A euryhaline intertidal fish.
Can withstand the changes in salinity a
tidepool experiences:
Less salty due to rain water or more
salty due to evaporation
Pup fish
Devil’s Hole
Variety (over 100 species) of rare
inland fish that exist in extreme
environments
(over 100°F and twice as salty as the
ocean)
Diatoms
Any of the thousands of species of
unicellular plant-like protists
Yellowfin tuna
Stenohaline marine fish with a low
tolerance for variation in salinity
Rainbow trout
Stenohaline freshwater fish with a low
tolerance for any salt
Polychaete worm
Marine annelid (segmented worm)
that demonstrates being an
osmoconformer. Tide pool species can
tolerate changes in salinity. Because of
this, it is a euryhaline organism.
chiton
Mollusk that can adapt to tide pool
conditions by surviving extreme
dessication (75% of its water)
limpet
Another intertidal mollusk. Survives
low tide by “clamming up.”
Seals its shell against rock substrate
Coralline algae
(encrusting)
Coralline algae (not a plant) is a red
algae (but can be purple or pink.)
completely marine (intertidal) and
hard because of calcium in cell walls.
Comes in two varieties: encrusting and
articulated