Day 8 – Corkscrew swamp (6/3/15)

Corkscrew Swamp

Saving the best until last we went to a place named Corkscrew swamp on our final day in the field.

The day started cool and overcast ~23°C/73°F but by the time we arrived at Corkscrew the temperature had gone up to 27°C/81°F and the sun was coming out. It turned out to be a scorcher!

There was no tour guide today, just a case of letting us walk around at our own pace and taking in the wonderful surroundings.

The start of the boardwalk
The start of the boardwalk

98% of virgin forest has been lost in the U.S. and Corkscrew swamp represents one of the best examples of the remaining 2%. It is the best preserved bald cypress (Taxodium distichum) swamp and most pristine habitat in Florida.

Cypress timber is incredibly valuable as it is a hard wood that naturally does not rot and this made it a target for industrial logging in the 1940’s and 1950’s.

Thankfully this area was saved by Corkscrew Cypress Rookery Association which was formed in 1954 and the National Audubon Society assumed management over the area in 1955 and who still manage it today.

The forest is over 500 years old with some trees exceeding 1,000 years in age with a total area of 13,000 acres.

A map of corkscrew swamp which illustrates the different types of habitat present.
A map of corkscrew swamp which illustrates the different types of habitat present.

As shown on the map above Corkscrew is broadly split into three different habitats: pond cypress (Taxodium ascendens), new growth; bald cypress, old growth and wet prairie.

This variance in habitat allows for a very biodiverse area supporting 64 species of reptile & amphibian, 34 mammal and 200 bird species.

The boundary between the wet prairie and pond cypress is much the same as the boundary between the pines and the cypress at FGCU. The boundaries of these habitats determined by small elevation changes and the action of fire and water.

The flatwood pines (Pinus spp.) can recover from fires faster than other species and would actually be out competed by other species if fires did not occur. These fires also spread to the wet prairie destroying any young cypress tree and maintaining the grassland.

There is some presence on an ecotone between the two, but it is limited by the building of the 2.25 mile boardwalk that has been built for visitors.

The boundary between the wet prairie and pond cypress (Taxodium ascendens).
The boundary between the wet prairie and pond cypress (Taxodium ascendens)

There is certainly a marked difference between the new growth pond cypress and old growth bald cypress. The pond cypress is dominated by young trees that have grown in a very regimented regime which blocks large amounts of light and limits the plants that can grow beneath them to mostly ferns (Pteridophyta).

The bald cypress is the complete opposite. There is a better mix of young and old trees and more importantly much more spatial variance between trees allowing more open spaces to allow light to penetrate and therefore a wider range of species to grow on the ground.

These more complex habitats are vital for certain species such as the butterfly (Encyclia tampensis) and ghost orchids (Dendrophylax lindenii) which grow high up just beneath the canopy as well as the wood duck (Aix sponsa) and the swallow tailed kite (Elanoides forficatus).

Above: the new growth of the pond cypress. Below: the old growth of the bald cypress. Notice how different they are in composition
Swamp 5 Above: the new growth of the pond cypress.
Below: the old growth of the bald cypress.
Notice how different they are in composition

Getting this close to such large trees also gives you a good view of some of the special adaptations these trees have as you can see in the picture below.

Although currently it is unknown what cypress knees do, as it has been confirmed they do not play a role in gas exchange like pneumatophores do in mangrove, there are a few hypotheses.

One of these is the cypress knees allow for a greater surface area for bryophyte growth then extends the oxic period as the standing water retreats in the dry season.

Two of the adaptations of cypress trees. Buttressing, for stablisation and cypress knees which currently have an unknown function.
DSCF6004 Two of the adaptations of cypress trees. Buttressing, for stabilisation and cypress knees which currently have an unknown function.

I also managed to finally get a few pictures of the native green anoles (Anolis carolinensis) of which I had only seen once before today. This is probably due to the fact that their niche is higher up in the trees than brown anoles (Anolis sagrei) that are often found at ground level.

This niche separation was very apparent at Corkscrew.

A green anole (Anolis carolinensis)
A green anole (Anolis carolinensis)

I also managed to bag my favourite photo of the trip and perhaps the most satisfying photo I’ve ever taken. All week I had tried to get a picture of a brown anole with its dewlap extended but I had failed every time.

Today though I finally managed to succeed!

The anole with it's dewlap tucked away...and finally after a week of trying I had my photo with the dewlap extended.
DSCF6030 The anole with its dewlap tucked away…and finally after a week of trying I had my photo with the dewlap extended.

The other lizard I saw today was a Southeastern five-lined skink, which made a pleasant change from all the anoles.

Southeastern five-lined skink, definately a fossorial lizard!
Southeastern five-lined skink, definitely a fossorial lizard!

The bird life here was also fantastic and it felt much more natural here than anywhere else that we had been. Even though you could stand quite close to the wading birds and the red shouldered hawks (Buteo lineatus), all the small birds were quite content to sit hidden in the trees twittering away.

The dense forest allows for excellent sounds transmission and acts as cover making it very difficult to spot the birds even when they were singing for extended period of time.

The most colourful bird I saw that day were the painted buntings (Passerina ciris) which winter here in Florida before moving further north to breed. Thankfully they weren’t too had to find as the frequented the bird feeders on a regular basis.

Painted buntings (Passerina ciris) on one of the many bird feeders near the visitor centre
Painted buntings (Passerina ciris) on one of the many bird feeders near the visitor centre

You can also feel the changes in microclimates/habitats as you walk around. Go up to the canopy level and it will be breezy and cool, but more exposed to sunlight. Drop back below and it will be darker but much more humid because the insulation from the surrounding vegetation.

Two different microclimate. At the canopy and beneath it
Swamp 4 Two different microclimate. At the canopy and beneath it

Another big aspect of corkscrew is changes due to the wet and dry seasons.

During the wet, summer months there is a high growth of plants and the breeding of fish in the deep pools of water that form.

During the dry season however the waters dry up and retreat leaving large amounts of fish condensed in small pools. This highly abundant, condensed source of food is the reason why birds breed during the dry season.

The dry season is also important for the reproduction of the cypress trees. Whilst the adult trees can survive submergence the young seedlings cannot.

A typical view of Corkscrew swamp during the dry season
A typical view of Corkscrew swamp during the dry season
A great white egret foraging in the shallow waters
A great white egret (Ardea alba) foraging in the remaining shallow waters

If you’re lucky you can sometimes see black bears (Ursus americanus). Apparently they used to be more common as they would be attracted by the food that tourists would bring.

It is because that was deemed unsafe that eating is now prohibited on the boardwalk.

Florida panthers (Puma concolor coryi) are also present here but you’d sooner win the lottery than see one here, most the pictures taken of them are from camera traps.

I did however see my first and only raccoon (Procyon lotor) of the trip here though. At least that’s something.

A raccoon (Procyon lotor) forages in the shallow waters
A raccoon (Procyon lotor) forages in the shallow waters

Unfortunately I didn’t get a chance to get round the full circuit as I was really taking my time and soaking everything in. But then again I’ve got a reason to come back.

It was a very enjoyable, interesting, inspiring and satisfying day and a great way to end the trip.

Ivory-billed Woodpecker

One animal I would have loved to have seen here, is the ivory-billed woodpecker (Campephilus principalis). Sadly the fate of this bird is currently unknown and is likely extinct but, like many others, I live in hope.

They were/are one of the largest woodpecker species in the world and were once abundant in the forest of southeastern USA and Cuba (although that was a separate subspecies, Campephilus principalis bairdii).

This species went into heavy decline partially due to hunting but primarily due to habitat loss due to deforestation.

Sadly even hefty monetary rewards of $10,000 in 2006 and $50,000 in 2008 yielded no results.

A drawing of an ivory billed woodpecker (Campephilus principalis) (Gambassa.com)
A drawing of an ivory billed woodpecker (Campephilus principalis)
(Gambassa.com)

The problem with this species and the other large woodpecker species that may also be extinct, the imperial woodpecker (Campephilus imperialis) which is/was the largest woodpecker in the world, is their large habitat requirements.

A pair of ivory billed woodpeckers requires 25km² in order to find enough food for themselves and their young.

To put it in perspective Corkscrew swamp is only 45km², at best enough space to just about squeeze in two pairs. Not enough space for a sustaining population.

Although they wouldn’t have been an ailing species before, because of their naturally low population and their low fecundity and longevity they were always a vulnerable species to habitat loss and exploitation.

There is some hope though. Although there has been no solid evidence that they still exist there has been numerous reported sightings since they last one was seen in Florida in 1944 as this map shows: IBW-range-map

Also despite the last of the cuban sub-species to be seen in 1987, it is estimated that 80% of the suitable habitat has not been searched.

The chances of ever seeing this species again is slim but maybe one day someone will get that one photo that proves they still exist. You never know maybe it’ll be you or me!

Final evening

For the final evening in Florida we headed to an area of barefoot beach for the final debrief as the sun set. They also announced the winners to the three competitions they had run during the week: best notebook, best nature photo and best people photo.

I was very happy to win the best nature photo for the picture of the heron eating a catfish I took whilst on the Anhinga trail in the Everglades.

A good way to end my time in Florida.

Here’s the timelapse I took of our final evening on the beach as everyone enjoyed themselves and the sun was setting.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s