apalachicola river, floodplain and bay largest forested floodplain in florida (112,000 acres)...

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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)

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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

85% of Apalachicola

River fish species

use floodplain

Stagnant conditions develop if sloughs are isolated for long periods

Fish trapped in floodplain will

die if water dries up in

isolated pools

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

BASELINE FLOWS

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

Pre-Dam FlowsFor Groups of Years Ranked by Average Annual Flow

Pre-Dam FlowsFor Groups of Years Ranked by Average Annual Flow

Pre-Dam Vs Post-Dam

Annual Rainfall Unchanged 10% LESS annual flow

(30% LESS Apr-Aug flow)

Pre-Dam Vs Post-Dam

Annual Rainfall Unchanged 18% LESS annual flow

(38% LESS Apr-Aug flow)