Title slide

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Title slide
Crabs
The Declining
Population
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General Information on the Blue Crab

• Can grow to 9 in.
• Crabs live in fresh water
• SAV are important to young crabs
• Crabs only live for 3 years

• Feed on clams, soft- shelled crabs,SAV, fishes
• Blue claws with green blue or olive green bodies

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Web of life
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Crab Reproduction and Life Cycle

• Blue crabs only mate once in their life.
• After mating the females migrate to high-salinity
  waters in lower estuaries and near-shore spawning
  areas.
• The female releases the fertilized eggs into a
  mass, or sponge that stays attached to her
  abdomen until the larvae emerge.
• The first stage larvae are called Zoeae and the
  stage lasts for 31 to 49 days.
• The second stage of a crabs life is Megalopa.
• When crabs molt they are called soft crabs and
  they are protected by the shelter of the S.A.V.
• The third stage is juvenile.
• The juveniles then become adult crabs.
• Blue crab maturity is reached from age of one to
  one and a half years for females but the males
  continue to grow.

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Crab dissection
We dissected blue crabs. We used scalpels
and scissors to break into the crabs exoskeletons
witch were extremely hard. Once the crabs were
open we saw the heart, brain, gills,and stomach.
Everything was wet, gushy and covered in a clear
jelly like liquid. The crab was still alive.
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numba of crabs in da bay

• WHAT WE CAN DO?
• 1.Limit the number of crabs pulled out the bay.
• 2.Plant SAVS in the bay.
• 3.Stop the construction of buildings near the bay.

In 2003 the state of the bay report,crabs scored
a 38out of a 100 which indicates a great demand
for improvement
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Save Me!
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Rockfish
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Description
can grow up to 5ft (60in) grows about 10-12in
in a year anadromous can live in salt,
brackish, and fresh water have up to 7 or 8
stripes
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Anatomy
In our group we disected a fish. With scissors
we cut open one side of the fish. First we cut
open the eyeball, then out of the eye we cut out
a small item called the lens, just like the ones
humans have. Next, we took a look at the organs.
We never found the brain but we found the heart,
the stomach,the liver and other intestines. We
really enjoyed our dissection.
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Save the Bay

• This graph shows the health of the animals in
  the bay. As you can see, rockfish population is
  very high but still not good enough. Blue Crabs
  have little lower than medium rate and
  struggling. Oysters are doing poorly. In the
  last 100 years, 99 of the oysters in the
  Chesapeake Bay have disappeared.

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How You Can Help (Solution)

• You can save the bay by not using so much
  fertilizer.
• You can save the bay by planting trees to stop
  erosion.
• Dont capture too many oysters because they
  filter the water.
• Learning about and studying the bay.
• Plant SAV(submerged aquatic vegetation) so fish
  have habitats.

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Why are Rockfish and Animals Important to the Bay?
Humans brought over MSX diseased oysters which
are killing oysters in the Bay. Humans eat
oysters, crabs, and rockfish.
Humans over -fish Rockfish
Oysters
Human
Crabs live in oyster shells
Humans create fertilized run-off, killing SAVs
Oysters filter and clean the Bay so SAVs can
receive light to grow
Rockfish
Eat baby fish living in SAVs
Rockfish eat baby crabs
SAVs
Crabs
Baby crabs live and breed in healthy SAVs. If
SAVs are not provided, they will die.
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The Ability to use Aquaculture on Rockfish
We had a tour of Horn Points aquaculture
laboratory. They are researching the
aquaculture of Atlantic Sturgeon and rockfish to
try to increase their population.
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The Oyster(Crassostrea virginica)

• A slideshow about the Chesapeake bays most vital
  bivalve creature.
• By Mr. Sammys group
• Brian, Drew, Daniel, Sam, Sean, Merrick, Allison,
  Rachel, and Anna

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Identification and anatomyIDCrassostrea
virginica (American oyster)

• There are many parts of an oyster. We were able
  to identify many of the parts when we dissected
  an oyster. The intestines were the best part.
  This picture shows the different parts of an
  oyster.

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Range and Habitat

• This picture shows the wide range of oysters
  throughout the bay area. Oysters live on the
  water bottom and are attached to hard surfaced
  objects where they spend their entire life.

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The oysters life cycle and span

• The oyster begins its life as an ovum and then
  once the sperm fertilizes the egg, it grows into
  an eyed larva. Then as it continues to grow, it
  is called a spat and finally an adult. The
  lifespan of an average oyster under controlled
  conditions is 10-12 years but in today's
  conditions the life span is around 3-4 years

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Environmental Impact

• They can filter over 1 gallon of water per hour
  per oyster making the bay less muddy.
• Their empty shells provide a perfect haven for
  hundreds of animals.
• As a favorite seafood, oysters are almost hunted
  to extinction.

This diagram shows the diversity of animals that
live on oyster shells. If oysters perish, so will
the animals that live on them.
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Reasons for Decline in Oyster Population

• Oysters numbers are declining each year. These
  are the reason for decline
• People harvest oysters each year .
• Some parasitic diseases effect oysters such as
  dermo(Perkinus Marinus) or MSX
  (HAPLOSPORIDIUM nelsoni)

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Restoration
Though the oyster population is only 1 of what
we had 100 yrs. ago, there are many projects
being done to help this. First, there is the
UMCES horn point hatchery which has increased
oyster population from 82million to over
2billion.The horn point hatchery currently spawns
90 of the oyster larva in the state of Maryland
though it is our only hatchery in Maryland. To
help, the federal government is contributing
50million which is aimed toward achieving a
10-fold increase over a 1994 baseline plus
another 25miilion from Maryland. There are also
projects which include the Maryland Department of
Natural Resources and the Oyster Recovery
Partnership.
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Boaters Impact on the Bay

• Positive Impact
• Boaters are now starting to use Non-toxic paint
  on their boats. They are also pumping their
  personal waste at pumping stations.
• People are now finding and planting more SAV.

• Negative Impact
• Boat propellers on the Bay have torn out
  a large amount of submerged aquatic vegetation
  (SAV). Boats also pollute Chesapeake Bay SAV
  beds.

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Since the dredges have been destroying SAV beds,
Maryland and Virginia are saving this from
happening by banning Hydraulic dredges to save
their bays. Also, some groups of people go and
plant SAVs.
CLAMMING BY HYDRAULIC DREDGING
Hydraulic dredges are machines that dig big
ditches in the mud and rip out the SAVs. They
are used for digging up clams and then suck up
everything in a big tube. In 1998, 1,849 acres of
SAV beds had been destroyed.
a
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Human Impact on the Bay
Watermen used to pull in about 64 million
bushels of oysters. During the past 30 years,
only 3.2 million bushels were harvested.
Oysters are very good at filtering the water and
are a big part of the ecosystem. By over
harvesting oysters, the water in the bay is
becoming more murky.
The more murky the water gets , the more SAVs
die. When SAVs die theres less food for
waterfowl and other animals. SAVs also provide
a nursery for young fish and other animals.
Dredges also pull up SAVs. Dredges are used to
harvest oysters.
Scientists are trying to save oysters because
theyre so important. Laws have been passed so
that watermen can only pull in so many. People
are replanting SAVs. Environmentalists are also
trying to educate people on how important
oysters and SAVs are. Even though problems with
oysters and SAVs still exist, people are still
trying.
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• The Problem
• Mute swans rip out 9,000,000 pounds of SAV
  plants and roots each year. They also scare away
  tundra swans and trample eggs and chicks.

Mute Swans

• The Solution
• People are removing swans and addling eggs,
  which means they are shaking the eggs so they
  will not hatch.People are also spreading the word
  of the mute swans destruction.

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• A Zebra Mussel is a temperate freshwater mollusks
  native to the Black,and Caspian Seas of
  Russia,and the Ukraine.
• The
  bad
• Damage water intake structures
• Cost the power industry 3.1 billion dollars since
  1993
• Attaches to boat motors, docks,and pipes have
  affected recreation industries
• The good
• Program Partners are developing a plan to
  prevent spread
• Resource managers are currently working to
  eradicate the Zebra Mussels population
• Boat cruisers, and scuba divers must be sure to
  thoroughly clean their boats, and equipment
  before leaving a waterway
• 
  ByCasonda Cornish

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Nutria

• Nutria are exotic animals that were brought over
  to Maryland for furs. They can dig up wetland
  roots. This can cause fast marsh erosion, a
  habitat loss for native species, pressure on
  muskrat species, and wetlands filtering capacity
  loss.The nutria can also come up and eat farmers
  crops.
• The solution to this problem is a project called
  Marsh RestorationNutria control in Maryland.
• This project will conduct research and test
  various control methods for getting rid of
  Nutria.

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SAV decline

• Bad water quality, disturbances of SAV beds, and
  alteration of shallow water habitat all
  contribute the decline
• In 1930 200,000 acres of SAVs were growing on the
  shoreline of the Chesapeake Bay, but by 1984
  there were about 38,000 acres of SAVs
• Mute swans are ripping the SAVs out of the water
  increasing decline
• Without SAVs the Chesapeake bay would become
  loaded with algae and the bay would have major
  habitat loss.
• When there is a high level of nutrients in the
  water, algae are formed and they block the
  sunlight so that the SAVs die.If the SAVs dont
  survive habitats are destroyed.

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SAV Restoration

• The bay programs goal is to plant 185,000 acres
  of SAVs.
• We are making special greenhouses with tanks in
  them to plant SAVs. After they they are grown we
  plant them in the river.
• Water quality is the key to growing SAVs. They
  need to have the right temperature and the mud
  cant be disturbed much because the sunlight
  cant get to the SAVs.
• We make buffers which are piles of rocks on the
  shore line or trees planted to stop erosion.

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SAV
Submerged Aquatic Vegetation
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What is SAV?

• SAV or (Submerged Aquatic Vegetation) is a plant
  that stops erosion, feeds waterfowl, and shelters
  many different kinds of water life.
• There are 16 different species of SAV. Some of
  them are
• Widgeon grass
• Wild celery
• Redhead Grass
• Eel grass.

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Algae

• When farmers put fertilizer on there plants and
  the rain comes to wash it away that causes a
  problem
• The fertilizer gets in the water and makes algae
• - The algae chokes the SAVs like smoke to us and
  it also blocks the sun light so they cant grow

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Mute Swans

Mute Swans are a problem to SAVs because when
they eat them, they pull up the roots so plants
cant grow back. Ducks and other birds arent a
problem because they just clip of the tops of
the SAVs. Mute swans also scare other birds and
ducks away.
To reduce the amount of mute swans, People are
messing with the swans eggs so they cant
hatch. People also build fences around SAVs so
That the Mute swans cant get in. Lastly,you
can plant more SAVs.
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Oysters BuffersBy Erin Alison

• How do oysters help?
• Why are they gone?
• How does their absence effect the bay?
• What is a buffer?
• How do they help?
• Are they working?

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Transplanting
Transplanting SAVs helps restore SAVs in the
Bay We transplanted trays of Redhead grass into
a cove thats connected to the Choptank
River When we transplanted it helped restore
SAVs so they can grow larger in population
Transplanting savs help restore the savs We
transplanted trays of
It will help the bay get healthy so it will be
like it was before Transplanting was fun