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Apalachicola River, Floodplain and Bay
Largest forested floodplain in Florida (112,000 acres)
Highest Species Diversity of any River System in
North America
UNESCO Biosphere Reserve
Outstanding Florida Water (OFW)
Habitat DiversityHabitat Diversity
Apalachicola River Floodplain hosts the highest Apalachicola River Floodplain hosts the highest biodiversity of any River System in North Americabiodiversity of any River System in North America
50 species of mammals 1300 species of plants
40 species of amphibians 80 species of reptiles 300 species of birds
See Apalachicola National Estuarine Research Reserve infoSee Apalachicola National Estuarine Research Reserve info
ProductivityProductivityHarvestHarvest
$200 million Local Seafood Industry, 90% of Florida Oysters, and 10% of US
oysters, plus shrimp, crab and finfish.
In 1994, Five Million lbs. of Seafood
were produced from the Apalachicola Bay region.
90% of all harvested species must spend some part of their life cycle inshore on the
marsh and seagrass environment, even the grouper caught offshore must rely on
this healthy environment.
Natural Features
of river and floodplain
Point Bar used for
Disposal Site
Cut bank
Slough
Levee
Swamp
Main channel
Forest Types Distributed by Elevation
Floodplain slough
Upland
Swamps
High Bottomland Hardwoods
Main channel
Low Bottomland Hardwoods
River Level Controls Water in Floodplain
Floodplain slough
Upland
Swamps
High Bottomland Hardwoods
Main channel
Low Bottomland Hardwoods
River Level Controls Water in Floodplain
Floodplain slough
Upland
Swamps
High Bottomland Hardwoods
Main channel
Low Bottomland Hardwoods
River Level Controls Water in Floodplain
Floodplain slough
Upland
Swamps
High Bottomland Hardwoods
Main channel
Low Bottomland Hardwoods
River Level Controls Water in Floodplain
Floodplain slough
Upland
Swamps
High Bottomland Hardwoods
Main channel
Low Bottomland Hardwoods
High and Low Water Seasons(before 1954)
Floodplain slough
Upland
Swamps
High Bottomland Hardwoods
Main channel
Low Bottomland Hardwoods
Fall
Summer
Early Spring
Severe drought
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Flo
w,
in c
ub
ic f
eet
per
sec
on
d2007 Flow in relation to Average Flow
Apalachicola River at Chattahoochee, FL
Average flow 1922-2007
2007 flow
Crawfish Integral Part of Food Chain
In the Apalachicola River System, crawfish are an integral part of the food chain and are an important food source of terrestrial and aquatic species.
.
• From the time Crawfish emerge from the ground, they are a major food source for fish, eels, turtles, otter, frogs, snakes, beaver, possum, young alligator, birds, and raccoons.
• High water is the time when aquatic species migrate into the flood plain to spawn and forage.
Crawfish Integral Part of Food Chain
• During the seasonal low water when the floodplain is not inundated, crawfish remain burrowed underground.
• Crawfish start emerging at the beginning of the seasonal high water typically between December & February, depending on flow regime.
• Upon emergence, crawfish have lost weight and immediately begin to forage for food.
• A crawfish's favorite food is soft, decomposing plant matter; however, they will eat just about anything – algae, snails, insects, plants, dead fish, etc. Crawfish are cannibals and will even consume other crawfish that are molting.
Crawfish Lifecycle
Crawfish Lifecycle
• After foraging above ground to regain weight, crawfish begin to spawn.
• In the mating process, males place a sperm packet on the underside of the female's belly.
Male top; female bottom
Crawfish Lifecycle
• She passes the eggs through the sperm down on to her tail and attaches them to the swimmerets, feathery apertures on the underside of the back section of her body.
• After the sperm packet is placed on the underside of the female crawfish, she curls up her tail and expresses the eggs.
• Eggs stay on the tail for at least four weeks. Variables such as food and water conditions can effect this gestation period.
• When hatched, the young remain attached to the mother until maturity.
• At the end of two weeks the young are capable of surviving on their own, at which time the mother flips her tail, releasing them into the water column.
•
Crawfish Lifecycle
• After being released into water columns by the mothers, babies settle to the bottom and begin to forage and grow.
• In 6-8 weeks they are large enough to catch in baskets.
Crawfish Lifecycle, continued
Crawfish Lifecycle Disruptions
• Crawfish are unable to complete their growing cycle when only a short period of floodplain inundation occurs.
• From 2002-2008, there was only 4-6 weeks of floodplain inundation, causing disruption in the crawfish lifecycle.
Crawfish Lifecycle Disruptions
• Rapid drops in water level below 8.5’ at the Blountstown gauge also disrupt the lifecycle. • It does not allow enough time for Crawfish to
burrow into the ground, leaving them exposed to predators and interrupts the lifecycle.
• When the water level drops below 8.5’, the Crawfish start burrowing down, and are burrowed in the ground at around 6’ water level.
Crawfish Lifecycle Disruptions
• Crawfish are unable to complete their growing cycle when only a short period of floodplain inundation occurs.
• From 2002-2008, there was only 4-6 weeks of floodplain inundation, causing disruption in the crawfish lifecycle.
Summary of Major Impacts:
DECLINING RIVER STAGEReduced flow
Woody debris removalLoss of Fish Habitat and FishReduction of aquatic species
DRYING OUT OF FLOODPLAIN FORESTDecrease in Forests Density
Loss of 4 million treesDisconnected Sloughs
DECLINING SEAFOOD HARVESTRiver flow drives the Bay and Eastern Gulf
Loss of Nutrients and Organics Increased Salinity, Temperature and Disease
Chain reaction thru Food Chain
Summary of Major Impacts:
• http://water.weather.gov/ahps2/hydrograph.php?wfo=tae&gage=blof1&view=1,1,1,1,1,1,1,1
The Apalachicola River System consists of the river and a 112,000 acre floodplain that ranges from 1-3 miles wide and discharges to the Bay.
The Apalachicola River System
Flow ComparisonApalachicola River at Chattahoochee, Florida
Pre-Dam Post-Dam
1923-1955 33-yr period before
filling of Lanier
1975-200733-yr period after
filling of West Point
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