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Hurricane Katrina (MS and AL General)

Resources at Risk for Mobile-Tensaw Delta, Mobile, Alabama.
I.	Spill Source Information
This report was prepared at 11:00 am EDT on September 14, 2005.
Information in the report is a general overview of the resources in the
area.

II.	Geographic Region Covered
The area covered by this report is the Mobile-Tensaw Delta and upper
Mobile Bay..  This area does not necessarily correspond to actual or
potential spill locations.  Consult other Hotline reports for location
information.

III.	Expected Behavior of the Spilled Material
This report is not based on any particular product but a general
overview of the resources in the area.

IV.	Shoreline Resources at Risk
The delta is mostly freshwater marshes, with the some brackish marshes
on the southern edge.  The northern part of the delta is freshwater
swamps.

V.	Biological Resources at Risk
Included are general statements about the effects of oil on the various
biological resources.  The effects may vary based on the type of
contaminant, since the behavior, toxicity, and availability of the
material can vary from product to product.
	Fish - The Tensaw and Mobile Rivers are migratory routes for
Gulf sturgeon (federally threatened), however they are not present at
this time of year.  Numerous species of fish are present at this time of
year including, but not limited to, Atlantic croaker (spawning), black
crappie, bay anchovy, bluegill (spawning), catfish, largemouth bass,
Gulf killifish (spawning), sheepshead minnow (spawning), striped bass,
shiners, silversides (spawning), red drum (spawning), silver perch
(spawning), spot, and threadfin shad.  In general juvenile and larval
fish are more sensitive to spilled oil than adults.  Fish in shallow
water areas are more likely to be impacted, since it is more likely that
there is a higher concentration of oil in the water column.  Surface
slicks usually do not have much of an impact on fish.
	Shellfish - Shellfish, present mostly in the northern part of
Mobile Bay and not in the delta, include blue crab (spawning), brown
shrimp, and white shrimp (spawning). Juvenile and larval life stages of
all of these shellfish are also present in the area.  Shellfish in
shallow water areas are more likely to be impacted, since it is likely
that there is a higher concentration of oil in the water column.
Surface slicks usually do not have much of an impact on crabs and
shrimp.  Crabs may be contaminated by a heavy sinking oil.
	Birds - Present in the area are numerous species of shorebirds,
wading birds, osprey, bald eagle (federally threatened), waterfowl,
white pelican, brown pelican, terns, double-crested cormorant, common
loon, and gulls.  October is the beginning of the migratory and
overwintering season for waterfowl.  Large numbers of waterfowl may be
in the area starting in October.
Diving birds (pelicans, cormorants) and waterfowl are usually at
greatest risk during oil spills, because they spend nearly all their
time on the water surface.  Waterfowl and wading birds may be directly
oiled, and can become oiled on the upper body and feathers by coming in
contact with oiled vegetation or wrack.  Shorebirds usually avoid oil,
but may be impacted by loss of feeding areas or intertidal prey,
particularly during migration periods.  Gulls and terns may be at risk
because they are often attracted to and will prey on sick or injured
prey.  This behavior may result in oiling of feathers and the ingestion
of oil.
Oiling of birds reduces the buoyancy, water repellency, and insulation
provided by feathers, and may result in death by drowning or
hypothermia.  Preening of oiled feathers may also result in ingestion of
oil which may lead to irritation, sickness, or death.  Bird oiling,
particularly waterfowl and wading birds, may continue even after the
floating oil slicks have been removed, depending on the extent of oiled
vegetation. 
	Reptiles - The Alabama red-bellied turtle (federally endangered)
is present throughout the wetland areas. Oil may cause irritation and
inflammation of the mucus membranes, especially around the eyes and
nostrils, in all of these reptiles.
	Habitats - Freshwater aquatic vegetation is abundant throughout
the delta.  The species include water celery, water stargrass, coontail,
Eurasian water-milfoil, southern naiad, pondweed, egeria, and hydrilla.
Some of these species are emergent and may be impacted by floating oil
slicks.

VI.	Human-Use Resources at Risk
This entire area is part of the W.L. Holland Wildlife Management Area or
the Mobile-Tensaw Delta Wildlife Management Area.  On the eastern side
of the delta on Big Island is Meaher State Park.