Augusta Scescke, Katie Fuentes, Melissa Jordan, and
Bethany Roeschley
Lake Michigan:
Tidal Flux daily/seasonal tidal flux/currents
Semidiurnal
“All bodies of water, large and small, are affected by the
gravitational pull of the moon and sun, and that applies to the
Great Lakes as well. Lake Michigan does experience tides.
However, they are minuscule compared to their ocean
counterparts. Tides on Lake Michigan range from as much as 1.5
inches in height and, just as on ocean shores they occur twice
daily. Such small variations are masked by wave action at the
beaches and by other short-period water-level fluctuations
cuased by wind and changes in pressure. One kind of fluctuation
in water levels induced by air pressure is known as seiche. On
rare occasions, it can bring a sudden, dangerous rise of several
feet on Chicago’s shores”. –Tom Skilling
Climate
"Wait a day and the weather will change" is an apt description of
weather in the Great Lakes region, especially in the spring and fall.
That's because the region is affected by both warm, humid air from the
Gulf of Mexico and cold, dry air from the Arctic. In general, the north
experiences cooler weather, while the south has warmer temperatures.
The entire basin experiences four distinct seasons.
The Great Lakes also have a big influence on the climate. Acting as a
giant heat sink, the lakes moderate the temperatures of the
surrounding land, cooling the summers and warming the winters. This
results in a milder climate in portions of the basin compared to other
locations of similar latitude. The lakes also act as a giant humidifier,
increasing the moisture content of the air throughout the year. In the
winter, this moisture condenses as snow when it reaches the land,
creating heavy snowfall in some areas, known as "snow belts" on the
downwind shores of the lakes. The shores of Lake Superior are prone to
this "lake effect" snow and have recorded up to 350 inches of snow in a
single year. During the winter, the temperature of the lakes continues
to drop. Ice frequently covers Lake Erie but seldom fully covers the
other lakes.
from: http://www.great-lakes.net/envt/refs/weather.html#overview
Bluegills
Spawning and life cycle: Bluegills spawn several times a year, in waters ranging from 65-
80 degrees. As such, the first round of spawning ocurrs earlier in southern waters (March
or April) and much later further north (May to July). While females leave the nest
immediately after spawning, males tend the eggs, fanning them with their caudal fins to
keep them aerated and free of debris. The protective father may even stay with the fry,
guarding them for several days.Growth depends on food availability and year-round
water temperature. A Florida bluegill can reach 4 inches in the first year, while a bluegill
from northern Wisconsin may only reach 1.5 inches in the same 12 month period.
Likewise, a 6 inch bluegill in Florida is generally from 2-4 years old,while in northern
Wisconsin, such growth might take as long as 9 years. Bluegills have been recorded as old
as 12 years.
Other common names: bluegill sunfish, northern bluegill sunfish, common bluegill, blue
sunfish, bluemouth sunfish, sunfish, pale sunfish, chain-sided sunfish, bream, blue
bream, bluegill bream, coppernosed bream, blackear bream, roach, dollardee, sun perch,
strawberry bass.
All of the above from:
http://www.warmwaterflyfisher.com/WWspecies/littlesunfish.htm
Bluntnose Minnow: Pimephales
notatus
Maximum length: 1.6 to 4.4 inches
Colors: Natural with black horizontal stripe
Temperature preference: 0.6- 21 degrees F
pH preference: near pH 7
Hardness preference: low to medium
Salinity preference: low
They are native to the U.S. They eat algae, insect larvae, diatoms, small
crustaceans, and sometimes fish eggs and fry. Like most minnows, they are a
schooling species.
Spawning males develop a black head with tubercles in three rows. Their body
turns bluish or nearly black. Spawning males develop a spongy pad on top of
their heads. Males are larger than females. Egg-laden females are fatter than
males. They spawn from spring to fall. Sticky eggs are laid underneath rocks
and logs. The male guards the nest. The female can lay 40 to 400 eggs at a time.
The eggs hatch in about eight to twelve days. Females begin breeding at about a
year of age while males peak at two years of age
Duckweed: Lemna minor
Duckweed is a light-green, free-floating, seed bearing
plant. Duckweed has 1 to 3 leaves, each 1/16 to 1/8 inches
long. One root protrudes from each frond. Duckweeds
grow in dense colonies in quiet water, as intense waves are
disruptive to their survival. It is common for more than one
species of duckweed to associate together in a colony.
Duckweed colonies are a habitat for micro-invertebrates. If
duckweed completely covers the surface of a pond for an
extended period it will cause oxygen depletions and
eliminate submerged plants by blocking the sunlight.
Several types of ducks consume duckweed and can
transport it to other bodies of water, perhaps why it is
commonly called duckweed.
Limestone Rocks
Limestone is a sedimentary rock that is mostly made
up of the mineral calcite. Because calcium is a key for
plant nutrition, soils that have limestone tend to be
pre-fertilized with calcium. Limestone is also an
important in man-made things like architecture. There
is limestone in Lake Michigan, as seen in the photo
above. But there is also limestone along the shores of
Lake Michigan, such as in the limestone cobble shore
which occurs along the northern Lake Michigan
shoreline.
The Common Hornwort
Hornwort plants are non-vascular plants and tend to
grow in places that are damp or humid or underwater.
It is also a rootless plant that often floats atop the
surface of the lake. The stems of the hornwort branch
off and form thickets for fish and especially fry to
retreat into. This is an aquatic plant and it is often fully
submerged in the water and is distinguished from
other aquatic plants by its stiff, forked leaves that are
shaped in whorls.
In Green Bay, Wisconsin there is a mixed semidiurnal tide. There
are successive highs and they are each lower than the previous high.
The shape of the shoreline of Lake Michigan and the various canals
affect the water levels of Lake Michigan. Also, since the Midwest
largely gets its water from Lake Michigan, its water levels will be
affected by consumption patterns. Another factor that may
influence the levels of Lake Michigan is climate: as storms could
cause surges, and humidity lowering the levels.
This is a photo of Lake
Michigan from space
showing blooms of
phytoplankton. You
can see the current
patterns of the lake
from the placement of
the blooms shown in
this photo.