Transcript What is a Strand Swamp?

Freshwater Forested
Wetlands
Strand Swamp
Craig Stokes
Description
What is a Strand Swamp?
• A shallow, forested, usually elongated depression or channel
situated in a trough within a flat limestone plain, and
dominated primarily by bald cypress (Taxodium distichum).
• a diffuse freshwater stream flowing through a shallow
forested depression on a gently sloping plain (Wharton et al.,
1976)
• depression on a gently sloping plain
• Strand Swamp Variation
• Smaller strand swamps may instead contain pond cypress (T.
ascendens).
Distribution
Range
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Strand swamps are restricted to South Florida
Not likely that they occur north of Lake Okeechobee
Mainly in Collier County
ex. Fakahatchee Strand and Corkscrew Swamp
Status
• S2/G2
• G2 = Imperiled globally because of rarity (6 to 20 occurrences
or less than 3000 individuals) or because of vulnerability to
extinction due to some natural or man-made factor.
• S2 = Imperiled in Florida because of rarity (6 to 20
occurrences or less than 3000 individuals) or because of
vulnerability to extinction due to some natural or man-made
factor.
Distribution
• Map shows majority of
Collier County
• Fakahatchee Strand
Preserve State Park
• Corkscrew Swamp
• Picayune Strand State
Forest
Conditions
Soils
• Peat and sand over limestone.
• Swamps with larger cypress and more diverse understory are
on deep peat that acts as a wick to draw moisture from
groundwater during droughts (Duever et al 1986).
Hydroperiod
• Range from 100-300 days.
• Water levels are typically greatest in June with increasing
rainfall.
• Lowest levels during winter and early spring.
• Water is deepest and longest near the center of the strand
swamp.
Strand Swamp Cross Section
Strand Swamp Interior
Aerial Photo of Fakahatchee
Strand
Identification
Strand vs basin/dome swamp
• Basin/dome swamps occur in closed depressions with little
water flow.
• Basin swamps north of Lake Okeechobee are roughly linear
in outline. These usually occupy basins of former lagoons
parallel to the coast that formed during periods of high sea
level.
• Strand swamps are found in troughs aligned with bedrock
lows in a very gently sloping limestone plain.
• Dome swamps can grow together which forms an irregular
strand. (Duever et al. 1986)
Identification
Strand Swamp vs Floodplain Swamp
• Floodplain swamps occur along streams and rivers, as
opposed to strand swamps which have an irregular network
of lower sloughs¹.
• Because of climate differences between each habitat type,
Strand swamps have a more tropical understory than most
floodplain swamps, which tend to be found further north.
• Sloughs¹- the deepest drainageways within swamps and marsh systems that are
indundated with slow moving or nearly stagnant water.
Identification
Dominant Plant Species
Red Maple (Acer rubrum)
Pond Apple (Annona glabra)
Dominant Plant Species
Bald Cypress
(Taxodium distichum)
Pond Cypress
(Taxodium ascendens)
Dominant Plant Species
Swamp Laurel Oak
(Quercus laurifolia)
Cabbage Palm
(Sabal plametto)
Dominant Plant Species
Strangler Fig
(Ficus aurea)
Coastalplain Willow
(Salix caroliniana)
Dominant Plant Species
Sweetbay
(Magnolia virginiana)
Swamp Bay
(Persea palustris)
Dominant Widlife Species
White-tailed deer
(Odocoileus virginianus)
Gray squirrel
(Sciurus carloinensis)
Dominant Widlife Species
Raccoon
(Procyon lotor)
River Otter
(Lutra canadensis)
Dominant Widlife Species
Little Blue Heron
(Florida caerulea)
Great Egret
(Casmerodius albus)
Dominant Widlife Species
American Alligator
(Alligator mississippiensis)
Cottonmouth
(Agkistrodon piscivorus)
Dominant Widlife Species
Red-shouldered Hawk
(Buteo lineatus)
Barred owl
(Strix varia)
Rare Species
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Plants
Animals
Birdsnest spleenwort
American Bird’s nest fern
Narrow-leaved strap fern
Tailed strap fern
Many-flowered catopsis
Cowhorn orchid
Fakahatchee guzmania
Hand fern
Fuzzy-wuzzy air-plant
Entire-winged bristle fern
Leafy vanilla
All restricted to south Florida
peninsula
• Short-tailed hawk
• Swallow-tailed kite
• Mangrove fox squirrel
(Threatened)
• Florida panther (Endangered)
• Florida black bear
• Southern mink (Threatened)
• Wood storks (Endangered)
• Eastern indigo snake
(Endangered)
Natural Processes
• Fire occurs very rarely in the interior of strand swamps.
• Can occur more frequently on the outskirts of the strand.
• These fires on the edges of strand swamps can help control
hardwoods.
• If left without fire, strands may convert to hyrdric hammock
(Penfound 1952).
• Muck fires that burn the peat can kill trees and lower the
ground transforming them into a slough. In these areas,
coastalplain willow will make a thicket.
Management: History
• Most strands were severely affected by cypress logging in the
early 20th century.
• Logged strands may be more vulnerable to fires, followed by
establishment of coastalplain willow thickets. (Alexander
and Crook 1973)
• Conversion of surrounding lands to pasture , citrus and
developments.
• Roads, levees, canals and trams were constructed for logging
and development which impeded water flow to and from
strands.
• Only within the past 15-20 years, there has been attempts to
restore strand swamps.
Management and Restoration
• Chemical/mechanical: useful for removal of exotic plant species.
(java plum, Peruvian willow, climbing fern, brazilian pepper, and
melaleuca).
• Any clearcutting operation should leave a cypress seed source
adjacent to the cleared area for regeneration
• Restore soils: peat in burned or drained strands
• Hydrological: installation of culverts, filling of canals and
destruction of unused roads to restore natural hydrology.
• Prescribed fire can be used at the edge of strand swamps to keep
back hardwood invasion. 30-200 years.
• Reconnecting appropriate ecological systems
• Acquire threatened strand swamps
• Conduct research
• Increase public awareness
Logging of Fakahatchee Strand