Posts Tagged ‘Altamaha River’

100 Species of Reptiles and Amphibians along the Altamaha River, Georgia

July 17, 2017

The corridor along the Altamaha River drainage is the best remaining wilderness in Georgia.  The land here is protected by 11 state wildlife management areas and 2 private landowners.  The Nature Conservancy owns Moody Forest, and the Orianne Indigo Snake Society owns land that hosts the greatest variety of reptiles and amphibians in the state.  Scientists have recently begun studying this largely undeveloped corridor.  From 2008-2016 scientists conducted the first comprehensive survey of reptiles and amphibians along this river system.  They used intensive group searches, turtle traps, and drift fences to find species; and they listened for frog calls.  Drift fences are barriers interspersed with pitfall traps.  Smaller reptiles and amphibians attempt to go around the barriers and fall into the traps.  Surveyors collected an astonishing 100 species, indicating the region has the richest diversity of reptile and amphibian species in the state.  Fort Stewart army base ranks 2nd with 97 species, and the Okefenokee Swamp hosts 88 species.

Image result for map of Altamaha River

Map of the Altamaha River Drainage.  The Altamaha is fed by 3 major tributaries–the Oconee, Ocmulgee, and Ohoopee.

Scientists catalogued 59 species of reptiles and 41 species of amphibians along the Altamaha River.  This number includes 17 species that are considered endangered by the federal and/or state governments, including indigo snake, diamondback rattlesnake, southern hog-nosed snake, rainbow snake, harlequin coral snake, pine snake, pine woods litter snake, slender glass lizard, mole skink, gopher tortoise, spotted turtle, southern dusky salamander, and gopher frog.

Surprisingly, cottonmouth water moccasins were found at less than half the sites surveyed, and they were absent from the main branch of the river.  The authors of this study suggest regular flooding “scours” riverside vegetation, eliminating the cover favored by the venomous snakes.  On the other hand river cooters (Pseudemys concinna) were found to be abundant in the river, though according to the preceding scientific literature they were not known to be present here.

Image result for river cooters scientific name

River cooters are common in the main branch of the Altamaha River.  Before the below referenced survey was conducted, reptiles and amphibians along this river were so little studied, this species was unrecorded in the scientific literature as living in the river.

Image result for red salamander scientific name

Red salamanders (Pseudotriton ruber) reach the southeasternmost limit of their range at the Altamaha River.  This waterway is a geographical barrier for 14 species of reptiles and amphibians.

species photo

The pine woods litter snake (Rhadinia flavilata) reaches the northern limit of its range at the Altamaha River.  This species grows to about 1 foot in length and mostly lives underground.  They are venomous but have rear fangs that are probably unable to break human skin.  They feed on small reptiles and amphibians and are no danger to people.

The reason such a high diversity of species occurs along the Altamaha River is the great variety of habitats.  The corridor hosts open water, bottomland hardwoods, cypress/tupelo swamps, longleaf pine savannahs, sandhills, Carolina Bays, and muddy seepage areas at the bottom of north-facing slopes.  However, the river itself serves as a barrier blocking movement of some species’ populations.  The Altamaha River is the southeasternmost range limit for 13 species, and the northernmost range limit for 1 species.

The high number of reptile and amphibian species is evidence the region of the Altamaha River has been climatically stable for millions of years.  The vicissitudes of Pleistocene climate fluctuations were muted here.  During cold arid stadials swampy wetlands shrunk in size but persisted as relics, while savannahs and scrubby sandhill habitat expanded.  Currently, wetland habitat has expanded but before European settlement grassland and scrub habitat were still extensive.  Western Georgia and Alabama have also experience long term climatic stability.  (See:

https://markgelbart.wordpress.com/2015/04/28/the-pleistocene-ridge-and-valley-reptile-corridor/

https://markgelbart.wordpress.com/2015/08/21/extralimital-species-of-pleistocene-aged-turtle-remains-found-in-the-upper-coastal-plain-of-alabama/

)  Like the black prairie region of Alabama, the Altamaha river also undoubtedly served as a refuge for species of reptiles whose current range was obliterated by an ice sheet during Ice Ages.  Blanding’s and wood turtles may have extended their range this far south then.  Extinct giant tortoises (Hesperotestudo crassicutata and H. incisa) likely lived alongside their smaller cousin, the gopher tortoise.  But otherwise the modern species list of reptiles and amphibians in the region is mostly unchanged from the Pleistocene.

Reference:

Stevenson, Dirk, and Houston Chandler

“The Herpetofauna of Conservation Lands along the Altamaha River, Georgia”

Southeastern Naturalist 16 (2) 2017

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The Moody Forest Natural Area

April 6, 2012

Between Reconstruction and World War II, lumber companies raped Georgia, clearcutting the beautiful forests that hadn’t already been cleared by greedy, slave-owning cotton farmers.  Jake Moody refused to let them destroy his beloved property, known locally as Moody Swamp.  He made his heirs promise not to allow its destruction.  In 1999 the descendents of his heirs sold 4500 acres to The Nature Conservancy, and today that organization shares ownership and management duties with the Georgia state government.  Thanks to Jake Moody’s foresight and love of nature, a remnant of old growth forest still exists here.

The Moody Forest Natural Area is located in Appling County, Georgia about a 10 minute drive north of Baxley and about a 10 minute drive south of the Hatch Nuclear Plant.  It can be accessed via East River Road, a well-maintained dirt road off Highway 1.  The dirt road is a smooth ride with very few bumpy rutted areas.  Despite being in the middle of nowhere, there are many nice houses on the opposite side of the road from the nature preserve.  The people living here must really enjoy country living–I saw not a single house for sale.  A fat old dog sleeps in just about every resident’s front yard, and many people keep cows, horses, and/or chickens.  One person even had an apiary.  I rank East River Road as one of the best places in Georgia for a naturalist to live.

Big slash pine.  Note the burned trunk.  The Moody Forest Natural Area is burned on a regular schedule to improve habitat for wildlife.  Mature pines and oaks usually survive light ground fires.

A swamp chestnut oak next to an old dwelling of some sort.  There’s space under the shack for chickens and a covered place to hitch the mule up to.  The oak is bigger than the slash pine in the above photo but a size comparison with a person wasn’t possible–by this time on our hike, the mosquitoes had chased my hiking partner into the car.  There are reportedly 200 year old post oaks and overcup oaks in the preserve.  Although dominated by pine, there are a surprising number of oaks here including swamp chestnut, post, Shumards or black (I can’t tell the difference between those species), southern red, overcup, and laurel.

There are 5 miles of trails in the preserve besides the access road that is adjacent to the Moody Family cemetery. Tavia’s Loop Trail is 3 miles long, and the River Trail is 2 miles long but because it’s not a loop that means it’s a 4 mile hike back and forth. If I was by myself, I would have hiked both, but there are no restrooms located anywhere near the preserve, and my wife needed one.  Spending money on a public lavatory probably isn’t a high priority for The Nature Conservancy.  I get the impression The Nature Conservancy doesn’t really want people to tour their protected sites.  The least they could do would be to build an old fashioned rustic outhouse.

Open pine parkland woods.  I didn’t see a single longleaf pine.  Instead,  I saw  loblolly and slash pines.

350 acres of longleaf pine-wiregrass savannah occurs at Moody, but I didn’t see any.  I hiked 1/2 mile up an access road and then another mile on Tavia’s trail, and I didn’t seen a single longleaf pine tree.  There was barely any wiregrass.  At the time of European colonization, longleaf pine savannah was the dominant landscape on the southeastern coastal plain.  Even in the protected Moody Preserve it takes up less than 10% of the land area, showing just how rare it is now.  Perhaps, if I had the opportunity to complete the whole loop trail, I would have come across it.  Instead, I saw mostly open pine parkland dominated by loblolly pine, slash pine, and post oaks.

Information I’ve read about Moody Forest makes no mention of ferns.  This type of fern is by far the most common plant in the undergrowth here. I think it’s royal fern, but I’m not sure.  It’s worthwhile  to see nature in person rather than just reading about it.

Here’s some wiregrass sprouting up after a recent burn.  The only people we encountered were a couple of workers with firestarting equipment.  By setting fires, they are mimicking Indian land management techniques .  Of course, before the Indians,  fires were more irregular and less frequent.  Pleistocene fires may have some times been devastating.  However, more often than not, Ice Age fires were  less severe because the megafauna consumed so much plant material there was less fuel, and dry climate phases fostered less plant growth.

A burrow dug by an endangered gopher tortoise.  I didn’t see the tortoise but I did see 2 rabbits just above the burrow.  I suspect they use the burrow for shelter.  I also saw a red-shouldered hawk carrying a cotton rat, turkey and black vultures, some gray squirrels, pileated woodpeckers, a red-bellied woodpecker, deer tracks, and lots and lots of mosquitoes and gnats.

A place to hitch up the ole mule.  The preserve needs an old-fashioned but working outhouse.  Women don’t like to squat in the wilderness.

This former homesite has 2 fireplaces.  This is one of them.  There are plenty of old ruins at Moody making it doubly interesting to explore.

The Moody Natural Area offers much to explore for the naturalist and the historian.  I barely scratched the surface during the brief but treasured time I was there.  I didn’t even have time to see any part of the River Trail.  Reportedly, 600 year old cypress trees stand there.

This cow pasture sits on the corner of Highway 1 and East River Road.  It’s the only really open space I saw in the vicinity of Moody Forest.  I pretended the cows were long-horned bison and imagined being in the Pleistocene.  There were Canadian geese by the creek, but I don’t think they’re visible in the photo.

Altamaha River Roadside Park

I didn’t have an opportunity to hike the River Trail in Moody Forest, but I wanted to see the Altamaha River up close.  The intersection off Highway 1 and the river has a Roadside Park that I investigated instead.

Graffiti on the Highway 1 Bridge that spans the Altamaha.  I love graffiti.

Spanish moss-draped post oaks.  This is an unusual combination of species.  Post oaks grow on dry upland sites; Spanish moss prefers warm moist lowland sites.  However at this site, they co-occur and dominate.

This is how I imagine a common Pleistocene landscape in Georgia might appear, but with taller grass and populated with bison and horses.

The Altamaha River.  This bend of the river almost looks like a lake.

A scary steep bluff.  Almost looked like a cliff from here.

Here’s proof that a kind of grape other than muscadine grows in south Georgia.  I think this is a River Grape which produces small blue fruit.

Paleomeander Scars along the Altamaha River

June 23, 2011

I’ve been a member of the Nature Conservancy for 22 years but have never visited one of their preserves.  I had a sudden urge to see one, and the Moody Natural Area excited my interest.  The Moody Natural Area is 8200 acres of sand scrub, open pine savannah, bluff forest, river bottomland forest, and cypress/tupelo swamp along the Altamaha River southeast of Vidalia, Georgia.  I’ll have to wait til fall though because summer is too !#$!  hot here in Georgia, and I don’t want to drag my poor wife and child out on another long field trip.  To appease my eagerness to see this remnant wonder of nature, I studied satellite photos of the site and found some interesting geology.  Below is a link to the satellite photo, but it won’t link directly to the area my sketch is based on.  To find it, pan to the right and enlarge.

http://maps.google.com/maps?hl=en&sugexp=ldymls&pq=satellite+view+of+appling+county,+georgia&xhr=t&q=Satellite+view+of+Baxley,+Georgia&cp=24&qe=U2F0ZWxsaXRlIHZpZXcgb2YgQmF4bGV5LCBHZW9yZ2lh&qesig=EOXfNfk3bgyRW1kycKKlYQ&pkc=AFgZ2tnGr_kwof9pAkEcEjqYCDUZ04s45pudfCHI7kM4NB0vUl9WZK6ZeoRYVvB9k7wrbFJc1ZikjlI9Te0c21MNqT5JMqKVew&rlz=1R2ADBF_enUS332&bav=on.2,or.r_gc.r_pw.&biw=995&bih=506&wrapid=tljp1308755019906021&um=1&ie=UTF-8&hq=&hnear=0x88f072d6b3107457:0x709010719d231b0,Baxley,+GA&gl=us&t=h&ei=bwQCTry2L4rEgAfHrLmgDQ&sa=X&oi=geocode_result&ct=title&resnum=1&sqi=2&ved=0CFAQ8gEwAA

Sketch of a satellite photo of Altamaha River adjacent to the Moody Nature Preserve.  Note the oxbow lakes and paleomeanders.  Both types of formations were former bends of the river that got cut off from the main channel.  The paleomeanders mostly dried up and filled with vegetation.  Both possibly formed as the Ice Age ended and precipitation increased making the river meander to a greater degree than it does presently.

Paleomeander scars are evident in satellite photos of the Altamaha River.   The Altamaha River used to flow through these spots, creating the visible incisions.  Later, the river shifted to its present location and as always is still slowly altering its position.  I don’t know whether geologists have ever studied the part of the Altamaha adjacent to the Moody Natural Area, but they have examined other areas along this mighty stream.  They’ve excavated braided sands in terraces that date to the Last Glacial Maximum (~30,000 BP-~15,000 BP).  I’ll explain what this means below.  But first, I’d like to suggest that the visible paleomeander scars in my sketch based on this location of the Altamaha may date to the end of the Ice Age (15,000 BP-10,000 BP) when the river meandered to a much greater degree than it does now.  Note that some of these scars still fill with water on occasion.

Geological History of Georgia’s Rivers

36,000 BP-30,000 BP

Prior to this time period, there is only a limited amount of data studied, so I begin here.  It’s likely, however, that time periods and climate phases discussed are repeated cycles that have occurred before.  Climate fluctated rapidly before the LGM, alternating between stadial and interstadial.  Stadials were periods of glacial expansion characterized by cold arid climate.  Though glaciers never came close to what’s now Georgia, the change in climate had a significant impact on Georgia’s rivers.  Long droughts lowered the water table and in many cases completely dried up tributaries.  The major rivers became clogged with huge sand bars and islands.  A decrease in vegetation along the rivers meant even more sandy sediment could accumulate.  The surrounding landscape consisted mostly of pine and oak savannahs.  Grasslands and sand scub grew in some places right up to the water’s edge.  Interstadials were periods of glacial retreats characterized by cool moist climate.  As the glacier to the north melted, moisture levels in the atmosphere increased as did precipitation.  Though average annual temperatures increased, they were still lower than those of today.  Interstadials likely had wet and dry seasons–late winter, spring, and early summer were wet; late summer, fall, and early winter were dry.  Floods during the wet season accumulated river sediment; winds during the dry season converted this accumulation of sand into dunes.  Because climate fluctuated during the this time period, Georgia’s rivers included a combination of meandering and braiding patterns.

30,000 BP-15,000 BP

Temperatures and precipitation rates fell dramatically during the Last Glacial Maximum as the northern glaciers expanded as far south as what today is central Ohio.  This caused water tables to drop creating braided river patterns.

The Platte River in Nebraska is an example of a present day braided river pattern.  Note the prevalent sparsely vegetated sand bars and islands.  Georgia’s rivers looked much like this during the Ice Age rather than their present day meandering patterns.

The climate was so dry that in some places eolian sand dunes born from riverine sand deposits blew across the landscape.  Thinly vegetated grassland grew to the water’s edge in some areas.  Geologists find braided river sands in terraces 0-15 feet above the floodplain adjacent to the rivers.  Some sand dunes formed during this era are quite large but today are covered with vegetation and more recent sediment.  Others have eroded away.

15,000 BP-5,000 BP

Temperatures rose rapidly at the end of the Ice Age, albeit the rise was interrupted by a precipitous fall in in average annual temperatures during the Younger Dryas cold phase.  As the Laurentide Glacier melted, there was a sudden increase in precipitation which caused massive storms and floods.  Georgia’s rivers broke out of their braided pattern and began to meander to a greater extent than they do today.  Flooding was more extensive as well.  For the first 5,000 years of this time period scroll bars were prevalent but these decreased in abundance later.  Scroll bars form when large meanders migrate and create ridges between old meander incisions.  Meanders peaked in intensity about the time the great glacial Lake Agassiz in Canada broke through the ice dams and released most of its water.  (See “Temporal Correlations between Lake Agassiz, the Okefenokee Swamp, and Ancient Flood Myths” from my January archives.)  Rivers still meander but to a lesser extent since the atmosphere has stabilized.

Reference:

Leigh, David

“Late Quaternary Climates and River Channels of the Atlantic Coastal Plain”

Geomorphology 2008