Gulf Coast by liuqingyan

VIEWS: 103 PAGES: 45

									 Gulf Coast’s
Barrier Islands
     MS Coastal Islands
•   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
•   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…
•   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-Under-
    the-Hill. Steamboat travelers
    encountered gambling houses,         Out for a night in Biloxi. Gambler Bob
    horse racing and cockfighting.       Thompson, center, in the lobby of the
• From Gambling in                       Avelez Hotel cashing in his winning bet
                                         against Salvatore Joseph Sicuro. The
  Mississippi: Its                       winner got to kiss Sicuro’s wife,
  Early History, Deanne S.               Josephine Louise Sicuro, left. Sicuro,
  Nuwer                                  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.
              *Split by Hurricane Camille in 1969 into
                 east and west Ship Island.
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   *Named after the Union ship USS
                 Massachusetts, which arrived at the
                 island during the Civil War.
  Cont.       *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                                   .
   –   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        Black Needlerush
Spartina alterniflora   Juncus roemerianus
                        Scheele
               Dune Grasses
Salt grass                  Dune grass: Sea Oats
Distichlis spicata          Uniola paniculata
12” Pushes salt crystals
 •
out through glands on the
leaves.
         Plants to watch for…
Arrowhead
Sagittaria spp., an      Eastern baccharis
obligate wetland plant   Baccharis halimifolia L.
                         endangered
                Common associates        Loblolly pine (Pinus taeda) has 3, 6" to
                                         10" needles per fascicle. Cones are 3"
                                         to 6" long, but they are light reddish-
Slash pine (Pinus elliottii) has         brown and persist for three years of
"brooms" of 2 to 3, 5" to 11" long       growth. Cones are far pricklier than
needles per fascicle at the ends of      slash. Bark is thick and divides into
rough twigs. Cones 5" to 8" in length.   irregular, dark brown scaly blocks.
Bark has large, flat, orange-brown
plates.
     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
    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/

								
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