Weedon Island - Sea
Lesson III. Weedon Island – Sea
pollution, nitrogen, nitrate, nitrite, ammonia
Inhabitants of Weedon Island
Some of the fish that can be
collected in a net at Weedon Island
include anchovy, sheepshead,
catfish, snook, blenny, stingray, and
At the water’s edge, an
observer might see a fish jumping, a
bird stalking a small fish, or a
Cormorant duck lazily drifting in the
As one might look further
out into the deeper waters that
surround the island, a dolphin
playing or a manatee might be
The waters and the muddy flats are
found on Weedon Island are great
place to observe the local reptile
Alligators, and turtles might
be found floating at the surface of
the water basking in the warm
Florida sun, while others may be
found in trees.
treefrogs, mangrove snakes,
diamondback terrapin snakes, and
rattlesnakes can all be found
throughout the preserve.
The Nitrogen Cycle
adapted from an article written by Dr. Kent Fanning for the St. Petersburg Times, St. Petersburg, Fl
The element nitrogen, which forms
up to 90% of the air that we breathe,
is also important in seawater.
the most abundant gas in the
atmosphere, and necessary for all
functions of life.
The movement of
nerve impulses, muscle contraction,
photosynthesis, growth, digestion of
food, vision and growth of hair,
feathers, or scales are only a few of
the processes that require nitrogen.
But nitrogen has a negative side.
Processes inside healthy tissues
produce a molecule in which
nitrogen is joined to hydrogen atoms.
This molecule is called ammonia, or
Ammonia is poisonous
and if not removed, or contained in
some way inside tissue, it causes
All animals, including fish and
people, must some how get rid of
this poison that is a by-product of
through their gills.
Mammals excrete urea, birds excrete
Ocean fish benefit from another
process that recycles the excess
are microscopic algae and they are
the basis of the food web for the
They are nearly
everywhere in the surface ocean.
They are usually starved for
nitrogen, and take ammonia out of
seawater whenever they encounter
Ammonia is their “favorite”
fertilizer during photosynthesis.
Phytoplankton growing on ammonia
“convert” a fish’s waste ammonia