Transcript Gulf Coast’s Barrier Islands - The Aquila Digital Community

Gulf Coast’s
Barrier Islands
MS Coastal Islands
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The Sand that forms our barrier islands comes
from the Appalachian Mountains esp. around
Georgia, so today’s sand dunes were perhaps,
thousands of years ago, a mountain top near
Georgia and South Carolina.
The main sand component is quartz.
The Mississippi Sound is an average of 12-15
feet deep.
Our islands are moving west and in 100’s of
years will eventually be in LA.
Gulf of Mexico Loop Current
Gulf Coast’s Barrier Islands
Mississippi’s Barrier Islands
Areas of Barrier Islands
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Wrack Line
Primary Dunes
Secondary Dunes
Maritime Forest
The Isle of Caprice
*Emerged around 1900
*Favorite excursion resort in 1920’s for New
Orleanians escaping the hot, humid summers.
*Storm erosion and harvesting of sea oats cut
back the island.
*The casino on it burned and then the island
disappeared completely with a hurricane in 1947.
A Cultural Side Note…
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Gambling in Mississippi began
before the new World was
“discovered”. American Indians
were fond of games and
gambling. Easy access by water
continued the tradition during the
early history of our country.
Gambling was also prevalent in
the Landing, a riverside region in
Vicksburg, and in Natchez-Underthe-Hill. Steamboat travelers
encountered gambling houses,
horse racing and cockfighting.
• From Gambling in
Mississippi: Its
Early History, Deanne S.
Nuwer
Out for a night in Biloxi. Gambler Bob
Thompson, center, in the lobby of the
Avelez Hotel cashing in his winning bet
against Salvatore Joseph Sicuro. The
winner got to kiss Sicuro’s wife,
Josephine Louise Sicuro, left. Sicuro,
rear, had his lounge business in the
Avelez Hotel. Circa 1946 photograph
courtesy Claude Sicuro.
Chandeleur Island
*The sand on
Chandeleur
comes from the
Mississippi River,
so their sand is
finer than our
sand.
*The island is
slowly sinking.
Cat Island
*In the shape of a “T”
*Erodes N to S because of the
MS River delta.
*Named “Isle aux Chats” (Cat
Island) because Bienville
and D’Iberville saw many
raccoons they thought were
cats.
*A lot of the island is still
privately owned.
Ship Island
*Split by Hurricane Camille in 1969 into
east and west Ship Island.
*10,000 British soldiers camped here
during the war of 1812, many of these
soldiers had bombarded the defenses
of Baltimore, Maryland and burned the
White House in Washington D.C.
*Union troops used it for their 1862
invasion of New Orleans.
*Became protected in 1971 by the US
Congress.
*Located 12 miles south of the coastline.
*Named Ship Island because of it’s natural
channel for ships.
Ship Island
Cont.
*Named after the Union ship USS
Massachusetts, which arrived at the
island during the Civil War.
*After the Civil War, it was used as a
quarantine station during the yellow
fever plague.
*Officials debated on whether a fort was
really necessary off the MS Coast,
however Secretary of War Jefferson
Davis pressured Congress to build the
fort.
*Construction began in 1859.
*After 2 years, only 8 feet of the outer walls
were constructed.
*The fort was complete in 1866.
*The cannon barrels weigh 50,000 pounds
and the cannons weigh 400 pounds. The
fort originally was supposed to have 37
cannons but only 17 were mounted.
Horn Island
*13 miles long.
*Named Horn because one of Sieur Bienville’s men lost a
powder horn there in the 1600’s.
*Army used the island as a biological warfare experimental
station in 1943. *Supposedly all live-stock and domestic
animals, except those used in experimentations, were
removed. There are reports that experimental hogs still
roam the island today. Only the chimney’s remain today.
*Local artist Walter Anderson stayed here during Hurricane
Betsy in 1965, tied to a tree.
*The Water’s family lived here from 1845 until a hurricane
drove them away. *They raised their own livestock and
crops.
*Protected in 1971 and designated a wilderness are in 1978 by
the US Congress.
*Supposedly the first map summarizing the discoveries of the
“western ocean” and the Gulf of Mexico by Christopher
Columbus shows Horn Island.
*Less fire ants on this island than ANY other barrier island on
the coast because no pesticides were used!!
Petit Bois Island
*6 miles long with a few little trees; means “little
wood”.
*This island used to be part of Alabama’s Dauphin
Island, however about 150 years ago a hurricane
carved it away and it has since migrated into MS’
waters.
*Protected in 1971 and designated a wilderness area
in 1978 by the US Congress.
Dauphin Island
*First and largest of
the barrier island
chain.
*14 miles long
*Indian tribes had a
religious temple
on it prior to
1519.
*Forested with oak
and pine trees.
*Named Dauphin
Island because
when explorers
found it in the
1600’s there were
100’s of dead
dolphins on it.
Island Vegetation Zones
• Salt and brackish marsh
– Saltgrass, rushes
• Tidal freshwater marsh
– Arrowhead, spikerush, bullrush
• Maritime shrub
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Rosemary (Rosmarinus officinalis) a woody, perennial herb with fragrant
evergreen needle-like leaves, a member of the mint family; "dew of the sea",
scrub oaks, eastern baccharis
• Maritime slash pine savannah
– Slash pine, salt meadow cordgrass
• Maritime evergreen forest
– Live oak, upland laurel oak, slash pine
Marsh Grasses
Smooth cordgrass
Spartina alterniflora
Black Needlerush
Juncus roemerianus
Scheele
Dune Grasses
Salt grass
Distichlis spicata
12”
• Pushes salt crystals
out through glands on the
leaves.
Dune grass: Sea Oats
Uniola paniculata
Plants to watch for…
Arrowhead
Sagittaria spp., an
obligate wetland plant
Eastern baccharis
Baccharis halimifolia L.
endangered
Common associates
Slash pine (Pinus elliottii) has
"brooms" of 2 to 3, 5" to 11" long
needles per fascicle at the ends of
rough twigs. Cones 5" to 8" in length.
Bark has large, flat, orange-brown
plates.
Loblolly pine (Pinus taeda) has 3, 6" to
10" needles per fascicle. Cones are 3"
to 6" long, but they are light reddishbrown and persist for three years of
growth. Cones are far pricklier than
slash. Bark is thick and divides into
irregular, dark brown scaly blocks.
Common Animals
Species: Ocypode quadrata
Ghost Crab
Species: Ocypode quadrata
Ghost Crab
• Scuttle at speeds up to 10 mph
• Sharp 360° vision which they use to see flying insects and catch
them in mid air. The ghost crab, however, cannot see directly up,
so it must burrow into the ground to prevent birds from catching
it.
• Ghost crab tunnels down four feet into the ground at a 45° angle,
creating 1-2 inch wide holes, which speckle the beach.
• At dusk, these crabs will sprint to the ocean in order to obtain
oxygen from the water which washes over their gills
• Ghost crabs hibernate during the winter, holding their breath for
six months, by storing oxygen in sacs near the gills. They can
also have a natural filter system which gathers oxygen from the
air, enough to survive for one year without entering into water.
Horseshoe Crab
Species: Limulus polyphemus
Horseshoe Crab
Species: Limulus polyphemus
• A marine chelicerate arthropod. Despite its name, it is more closely
related to spiders, ticks, and scorpions than to crabs
• The female is typically 25 to 30 percent larger than the male.
• Before becoming mature around age 9, they have to shed their
shells some 17 times. They can live for as long as 31 years.
• Lay 15,000-64,000 eggs per female
• Horseshoe crabs are distant relatives of spiders and are probably
descended from the ancient eurypterids (sea scorpions). They
evolved in the shallow seas of the Paleozoic Era (540-248 million
years ago). The four species of horseshoe crab are the only
remaining members of the class Merostomata, one of the oldest
classes of marine arthropods. Horseshoe crabs are often referred to
as living fossils, as they have changed little in the last 445 million
years
• Horseshoe crabs possess the rare ability to regrow lost limbs.
Horseshoe Crab
Species: Limulus polyphemus
• Horseshoe crabs are valuable as a species to the medical research
community. The horseshoe crab has a simple but effective immune
system. When a foreign object such as a bacterium enters through a
wound in the animal's body, a substance called Limulus Amebocyte
Lysate (LAL) almost immediately clots into a clear gel-like material,
effectively trapping the foreign body. LAL is used to test for bacterial
endotoxins in pharmaceuticals and for several bacterial diseases. If
the bacterium is harmful, the blood will form a clot. Horseshoe crabs
are helpful in finding remedies for diseases that have developed
resistances to penicillin and other drugs. Horseshoe crabs are
returned to the ocean after bleeding. Studies show that blood
volume returns to normal in about a week, though blood cell count
can take two to three months to fully rebound. A single horseshoe
crab can be worth $2,500 over its lifetime for periodic blood
extractions.
Blue Crab
Callinectes sapidus
Blue Crab
Callinectes sapidus
The number of eggs in a single sponge
ranges from 700,000 to one million.
It takes about two weeks for the eggs to "ripen"
and be released into the water to hatch. It is
illegal in many states to possess sponge crabs.
Blue Crab
Callinectes sapidus
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Greek calli="beautiful", nectes="swimmer", and Latin
sapidus="savory"
The blue crab is an omnivore, eating both plants and
animals. Blue crabs typically consume thin-shelled
bivalves, annelids, fish, plants, and nearly any other item
they can find
The most important commercial crab species in the Gulf
of Mexico.
Though she mates only once, she stores a portion of the
sperm and is capable of producing fertile eggs for one or
more additional "sponges" during her life. Males will
mate throughout their life span.
It has been estimated that a crab (including larval molts)
will shed approximately 25 times during its life
Brown Pelican
Pelecanus occidentalis
Brown Pelican
Pelecanus occidentalis
• Shooting for feathers and to "protect" fishing caused
declines in pelican populations in the first half of the 20th
century. Pesticide poisoning, especially by DDT, caused
severe declines across the range in the late 1950's and
the expiration from Louisiana ("the pelican state"). It was
listed as Endangered throughout the range in 1970. The
ban on DDT led to a population recovery, and it was
removed from the Endangered Species list in Atlantic
Coast states in 1985. Breeding numbers in most states
are stable or increasing, and the total population in the
United States now exceeds historical levels.
• Is the smallest of the eight species of pelican, although it
is a large bird in nearly every other regard. It is 106-137
cm (42-54 in) in length, weighs from 2.75 to 5.5 kg (6-12
lb) and has a wingspan from 1.83 to 2.5 m (6 to 8.2 ft).
Laughing Gull
Larus atricilla
Laughing Gull
Larus atricilla
• Nest colonies in northeastern United States were nearly
eliminated by egg and plume hunters in the late 19th
century. Populations have increased over the last
century, following protection.
• The male and female Laughing Gull usually build their
nest together. If a male cannot find a mate, he may start
building a nest platform and then use it to attract a
female.
• Laughing Gulls take three years to reach adult plumage.
Immature birds are always darker than most similar
sized gulls other than Franklin's. First year birds are
greyer below and have paler heads than first year
Franklin's, and second years can be distinguished on the
wing pattern and structure.
Shrimp
White: Litopenaeus setiferus
Pink: Pandalus jordani
Brown: Farfantepenaeus aztecus
Pink Shrimp
White Shrimp
Brown Shrimp
White Shrimp
Litopenaeus setiferus
• Few white shrimp live as long as a year, and the
maximum lifespan is about two years
• Spawning happens as far as 9 km from the
shore, and involves between 50,000 and 1
million eggs being released at a time. The eggs
sink to the bottom of the water as they are
released and hatch 10-12 hours later.
• Juvenile shrimp can grow 1.2 mm per day during
late spring and summer months, but growth is
slow in the spring.
Brown Shrimp
Farfantepenaeus aztecus
• Adults are typically 30–50 mm (1¼–2 in)
long, although individuals up to 90 mm
have been recorded.
• They live in shallow water, which can also
be slightly brackish, and feed nocturnally.
During the day, they remain buried in the
sand to escape predatory birds and fish,
with only their antennae protruding.
Pink Shrimp
Pandalus jordani
• Sexually dimorphic, with large males attaining a
length of 169 mm, and large females reaching
over 280 mm
• Individuals reaching sexual maturity may live a
year or more
• Sub-adults and adults show pronounced diurnal
activity patterns, remaining burrowed in the
substratum during the daylight hours, and
becoming active in the water column in the
evening.
Portuguese Man of War
Physalia physalis
Portuguese Man of War
Physalia physalis
• Commonly thought of as a jellyfish but is actually a siphonophore—a
colony of specialized polyps and medusoids.
• It has no means of propulsion, but is moved by a combination of
winds, currents, and tides. Very rarely is a single Portuguese Man O'
War seen, but rather the discovery of one is usually a warning of
more to come
• To escape a surface attack, the pneumatophore can be deflated
allowing the Man O' War to briefly submerge.
• Below the main body dangle long tentacles, which sometimes reach
ten metres (33 feet) in length below the surface, although one metre
(three feet) is the average
• Stings from the tentacles can be dangerous to humans, but usually
are not. These stings usually cause excruciating pain, and have
even been the cause of a few deaths. Detached tentacles and
specimens which wash up on shore can sting just as painfully as the
intact creature in the water for days to weeks after their detachment.
The venom can travel up to the lymph nodes and may cause,
depending on the amount of venom, more intense pain. Medical
attention is usually necessary, especially in extreme cases.
Comb Jellies
Pleurobrachia pileus (Sea Gooseberry)
Cestum veneris (Comb Jelly)
Comb Jelly
Sea Gooseberry
Comb Jellies
Pleurobrachia pileus (Sea Gooseberry)
Cestum veneris (Comb Jelly)
• Despite their appearance, they are zoologically not
jellyfish, not least because they lack the characteristic
cnidocytes (stinging cells) but have connective tissues
and a nervous system. There are close to 150 described
species of ctenophora spread throughout the world's
oceans, from shallow estuarine waters to the deep sea
• The light emission of ctenophores is not
bioluminescence but merely diffraction of ambient light,
• There is no separate exit from the stomach apart from
two 'anal pores', which despite their name appear to be
only moderately used for excretion, so indigestible waste
is principally expelled via the mouth.
Sand Fleas
(Mole Crabs)
Genus: Emerita
Sand Fleas
(Mole Crabs)
Genus: Emerita
• Mole crabs live under sand in shallow water near the
shore, and live from two to three years. They have the
color of rippled sand at the water's edge and live mostly
buried in the sand in the zone where the waves wash up
onto the beach, with their antennnae reaching into the
water forming a V-shaped obstacle in the water as the
wave recedes. These antennae filter plankton and
organic debris from the water. Mole crabs also eat the
tentacles of Portuguese man o’ war, which are collected
by winding the tentacle around the mole crab's leg. Their
camouflage protects them from their predators - chiefly
fish and birds.
A great resource for teachers
• http://www.marine-ed.org/bridge/