The I'On Swamp

Nestled away in the southern reaches of South Carolina’s Francis Marion National Forest lies a swamp with a long and storied history. This forested wetland—the I’On Swamp—lies on the upper reaches of the Wando River, a tributary to the Cooper River and ultimately the Charleston Bay. I visited the I’On Swamp back in October with the intent to hike a short interpretive trail, look for some reptiles, and otherwise see an area I had often heard about. The I’On Swamp is truly an alluring site with a fascinating history with regard to geology, biology, and human history. When I tried to learn more about the history and nature of this swamp, I quickly learned that there are many bits and pieces of information scattered across the internet, but it was hard to find a more encompassing article on the swamp. With this post, I hope to weave together these bits and pieces into a story on how humans utilized and modified the I'On Swamp throughout history, and how this utilization and modification impacted three now-extinct species of birds which used to inhabit the swamp.

Geological Setting

The story of the I’On Swamp begins long ago when a series of complex geological processes took place that ultimately led to the formation of this southern freshwater swamp. Due to both uplifting forces in eastern North America and periodic sea level rises and falls driven by glacial cycles, the Atlantic Ocean receded from the coast of what is now South Carolina in a series of “steps”. Each time the ocean receded from the then-current coast of South Carolina, a new shoreline and a new barrier island system were consequently formed. As this new shoreline and new barrier island system were formed, the previous shoreline and barrier island system would be left high and dry on the mainland. This step-like process led to the creation of a series of scarps and terraces. Essentially, a scarp is a narrow, but long, hill formed from the old sand dune system that was present on what used to be the barrier island system, while a terrace is a flat, slightly sloping area behind the scarp that used to be both the back half of the barrier island as well as the shallow marshes and/or lagoons behind the island.

Figured modified from "Revision of the Pleistocene Dorchester and Summerville Scarps, the inland limits of the Penholoway Terrace, central South Carolina," by W.R. Doar and Ralph Willoughby (South Carolina DNR Geological Survey).

One of these step-like coastal recessions occurred around 85,000 years ago. This specific recession formed the Mount Pleasant Scarp and the Princess Anne Terrace, and these formations bring us to the geological context for the I’On Swamp. Because the Atlantic Ocean receded in a step-like pattern along the South Carolina coast, a series of repeating scarp-terrace-scarp-terrace-scarp formation were created. Subsequently, each low-lying terrace was bound on its east and west sides by a higher scarp. (If you want to really dive into this topic, I suggest reading “Geneticstratigraphy and geochronology of last interglacial shorelines on the central coast of South Carolina" by Russell Willis) In the case of the Princess Anne Terrace, to the west was the Awendaw Scarp and to the east was the Mount Pleasant Scarp, both of which were higher in elevation than the terrace itself. Because of the resulting U-shaped depression, water collected in the Princess Anne Terrace, forming a wetland. After the last ice age ended, and the temperatures in the area warmed, plants and animals that are characteristic of a southern freshwater swamp emigrated into this wetland, forming the original primeval I’On Swamp. This swamp went on to form the headwaters of the Wando River, which drains the southern half of the Princess Anne Terrace.

Human History and Land Use

For the majority of the past several thousand years, this area had been a mature swamp forest. Swamps are a type of wetland which are dominated by trees and are either permanently or seasonally flooded. Ivory-Billed Woodpeckers, American Alligators, River Otters, and a whole host of other animals lived throughout this old-growth swamp. The area was not devoid of humans, however. In fact, Native Americans first began inhabiting South Carolina around 9,000 to 10,000 years ago. Around 3,500 years ago, tribes began to form more permanent settlements along the coast of South Carolina right near the I’On Swamp, which is itself only about five miles from the Atlantic Ocean. It is important to note that these native peoples did impact and modify the land, including the I’On Swamp. The idea of Native Americans “living alongside the land” is a bit of a misconception. We now know that Native Americans did indeed alter the land to benefit them, just not as on a large-scale manner as people do nowadays.

The greatest environmental impact from the Native Americans in this region stemmed from their use of fire. Natural wildfires—ones started through lightning strikes—historically occurred frequently throughout the Lowcountry of South Carolina, with many habitats in the Lowcountry being dependent on such wildfires. Some habitats, such as Longleaf Pine savannas, experienced natural fires as often as 1-5 years. Swamps like the I’On Swamp, however, experienced natural fires once every 25-100 years. In addition to the natural wildfires which occurred throughout the Lowcountry, many fires were also started by the Native Americans living in the region. These native peoples made ample use of low-intensity burns to both open the understory for easier to travel and make the areas more conducive for hunting, among other reasons. There is no doubt that low-intensity fires started by the native peoples impacted the I’On Swamp prior to European settlement.

European exploration of the South Carolina coastal areas began in the 1500’s, but it wasn’t until the mid-1600’s that European settlers emigrated to the region in significant numbers. In 1670, British settlers established a city called Charles Town only 20 miles southwest of the I’On Swamp. Charles Town—which we now know as Charleston—rapidly grew. This rapid growth led to other colonists moving out from Charleston to settle the surrounding land. The area immediately around the I’On Swamp itself began to be earnestly settled in the 1690’s.

It was around this time that the economy of coastal South Carolina began transitioning from one dominated by fur trading to one dominated by rice cultivation. From 1700-1860, rice was the crop to grow in coastal South Carolina. Rice cultivation became the dominant force that impacted the I’On and other nearby swamps during this period, and the effects can still be seen today.

Before I dive into how rice cultivation changed the landscape of the I’On Swamp, I want to briefly talk about rice cultivation in the Carolinas. While researching articles for this topic, I relied heavily on Dr. Hayden Smith’s Ph.D dissertation entitled “Rich Swamps and Rice Grounds: The Specialization of Inland Rice Culture in the South Carolina Lowcountry, 1670-1861.” This dissertation was fascinating to read, and is very approachable for those (like me) without any real background knowledge in the topic. If you’re interested in this sort of historical subject, I highly recommend reading the piece, which you can find at this link.

There are two main types of domesticated rice in the world—Asian Rice (Oryza sativa) and African Rice (Oryza glaberrima). The rice we eat today are cultivars of Asian Rice, but the rice that was grown in the colonial United States was most likely a cultivar of African Rice, specifically a cultivar called Carolina Gold. African Rice was originally brought to the Carolina colonies by European explorers and traders that traveled to Africa. When rice cultivation in the Carolinas began expanding in the early to mid 1700's, the colonists started to utilize enslaved peoples from Africa to work the rice fields. There were two main reasons for this. First, the colonists needed more people for labor, and African slaves were sadly a horrific way to satisfy this need. Second, many of these enslaved peoples came from the Senegambia and Sierra Leone regions of West Africa. The peoples of West Africa had been practicing rice cultivation for nearly 2,000 years, and during this time they had developed a very efficient method for growing the rice using dikes and flooded fields. Enslaved African peoples brought with them this knowledge of rice cultivation, which was then implemented in the Carolina Lowcountry.

There were two main methods of rice cultivation in the Carolina Lowcountry—tidal rice cultivation and inland rice cultivation. As the name suggests, tidal rice cultivation relied on the tides, which moved water in and out of impounded rice fields near the ocean via canals. Inland rice cultivation, on the other hand, relied on gravity. Inland rice plantations utilized the principle that water flows downhill from higher elevations to lower elevations. Due to the location of the I’On Swamp, tides were not a factor in the movement of water. Consequently, plantations in the I’On Swamp utilized the inland rice cultivation method.

A 200+ year old Wythewood Plantation canal along the I'On Swamp Interpretive Trail.

Here is a very brief overview of how the inland rice cultivation process worked in the swamps of the Carolina Lowcountry. The enslaved peoples would first clear the land of trees and shrubs by using fire, axes, and saws. After the land was clear, they would then build elaborate earthen dikes that channeled and controlled the water found within the swamp. A reservoir would first be created at the highest elevations within an area (which might have been only a mere 3-6 feet higher than the “low” parts of the surrounding swamp). Impounded fields where the rice would grow would then be created at the middle or lower elevations. Finally, canals and channels would be created to connect the reservoir to the rice fields, and the rice fields to the natural creeks and rivers throughout the swampland. At each point where one section met another, a rice trunk—which are essentially watertight gates/valves—would be installed that could either be opened or closed. If the rice fields needed to be flooded, they would open rice trunks on the reservoir dam and allow the water to flow downhill through channels and into the rice fields. If the rice fields needed to be drained, rice trunks at the lowest points of the fields would be opened, allowing the water to flow out of the fields and into channels leading to a creek or river.

As you can see, changing a mature swamp to a rice plantation alters not only the vegetation of a swamp, but the entire landscape as well. This level of landscape modification would wreak havoc on the ecology of an area like the I’On Swamp. Some animals or plants undoubtedly benefited due to the change from dense swamp forest to a more open marshland—say, for example, some species of migrating shorebirds or waterfowl—but the overall impact was negative for the majority of the species that were originally present.

The peripheries of the I’On Swamp experienced development for rice cultivation as early as the 1750’s, if not a bit earlier. At this time, the swamp was known as the Wappetaw Swamp. “Wappetaw” was a Sewee Indian term meaning “Sweet Water,” and was a name that tribe had given the swamp. From the 1790’s to the 1810’s, more and more plantations popped up in the area, many of which were pushing further and further into the swamp. At the same time, several of the richer plantation owners in the area began buying out some of the smaller plantations to consolidate land. They did this to both expand their rice production and—perhaps most importantly—gain more thorough control of the water for their fields.

As this consolidation occurred, a few “big name” plantations that controlled thousands of acres formed. These were the Fairlawn Plantation in the southern portion of the swamp, the Wythewood Plantation in the northwestern portion, and the Clayfield Plantation in the eastern portion. The early owner of the Clayfield Plantation was Jacob Bond I’On, which is where the current name for the swamp stems from. From what I could gather, most people called this swamp the Wappetaw Swamp during the 1700’s and 1800’s, and the name didn’t transition to the I’On Swamp until the 1900’s. As an interesting aside, this part of the Lowcountry spoke non-rhotic English in the 1700's and early 1800's, meaning that people born and raised in this region did not pronounce the "R" sound in words. Jacob Bond I'On's last name is actually a modification of the name "Iron." This name was modified to reflect how people were pronouncing the name, and the spelling stuck, both with the I'On family, but also the I'On Swamp.

Old Wythewood Plantation rice dike (the "trail" running through the right side of the photo).

By the mid 1800’s, essentially all of the I’On Swamp had been modified for rice cultivation. However, that isn’t to say that all the land had been turned into rice fields. There were probably still pockets of young, secondary growth swamp forest in places that had originally been logged in order build canals and dikes, but that were not ultimately used as a rice field. When the Civil War broke out in 1861, the rice industry in the south collapsed. Essentially all the commercial rice cultivation in the I’On Swamp ceased by 1870. Although commercial production ceased after the Civil War, subsistence rice production by now-freed African Americans continued in small tracts around the I’On Swamp for the next 30 years, most prominently in what had been the Wythewood Plantation—a plantation which will come into play later on in this story.

The forest began to regrow in any part of the swamp which were not being used for subsistence farming during this post-Civil War period. Hardwood trees characteristic of southern bottomland forests—various oaks, tupelos, Sweetgum, etc.—began recolonizing the abandoned fields and dikes. By 1900, essentially all of the I’On Swamp was reforested by a young, secondary growth forest. This extensive tract of hardwood trees was quickly noticed by a booming southeastern timber industry. Between 1900 and 1910, a large timber company bought most of the old plantation lands in the I'On Swamp. By 1920-1925, this company had clear-cut nearly all the trees throughout the I’On Swamp.  

Various hardwood species regrowing in the I'On Swamp.

After timber companies clear-cut the I’On Swamp and nearby swamps such as the Wambaw and Hellhole Swamps, the land “lost its value,” at least in the eyes of the timber companies. The government, however, saw some promise, and the Department of the Interior began purchasing these tracts of land starting in the late 1920’s. These newly-purchased lands became the foundation for Francis Marion National Forest, which was formally established in 1936. Nowadays, the majority of the coastal land between Charleston and Georgetown is part of this national forest, and that includes most of the I’On Swamp itself.

For the rest of this post, I want to focus on the Ivory-Billed Woodpecker, Carolina Parakeet, and the Bachman’s Warbler. These three species—all of which are now extinct—used to inhabit swamps throughout the southeastern United States, including the I’On Swamp itself. Sadly, most of the swamps in the southeastern United States have been heavily modified or completely destroyed by humans over the past 300 years, and these actions have either directly or indirectly led to the extinction of these three bird species. I want to explore how human land use of the I’On Swamp over time impacted these three birds, and how and why they became extirpated (locally extinct) in the I’On Swamp.

Ivory-Billed Woodpecker

John James Audubon Letters and Drawings, 1805-1892, MS Am 21 (31), Houghton Library, Harvard University

I’ll begin with the Ivory-Billed Woodpecker, as this was the first species to become extirpated in the I’On Swamp. The Ivory-Billed Woodpecker required mature bottomland swamps, a habitat that used to exist in large tracts across much of the southeast. In the 1800’s, especially after the Civil War, the majority of these virgin swamps were either logged, drained, or in some other way modified. With the destruction of the Ivory-Billed Woodpecker’s habitat, the Ivory-Billed Woodpecker’s populations followed.

The Ivory-Billed was known to be common throughout the swamps in the Lowcountry of South Carolina, and they most certainly inhabited the I’On Swamp for hundreds, if not several thousands, of years. Their time in the I’On Swamp probably came to an end between 1750 and 1770 when the swamp experienced the first wave of logging and modification to make way for rice fields. From historical and contemporary accounts that I’ve read on the plantations of the I’On Swamp, there were a few sections of the swamp forest that remained relatively unscathed during this early agricultural time. It’s possible that these tracts could have harbored a few individuals into the mid 1800’s, but these tracts were most likely too small for a population of Ivory-Bills to sustain itself.

Topographic map of eastern Francis Marion National Forest with the names of main swamps added in. For a greater geographical context, just past the bottom left hand corner is the Charleston, SC, area, and outside the top right corner is Georgetown, SC. This map was modified from a USGS Topographic Map.

The last confirmed Ivory-Billed Woodpecker in South Carolina was observed in 1938 on Wadmacon Island. Wadmacon Island is an island in the lower Santee Swamp (which runs along the Santee River), and is only a mere 20 miles north of the I’On Swamp. Although Ivory-Bills were without a doubt gone by 1915 from the I’On Swamp itself (which, if you remember from earlier, was completely clear-cut by this point), a few individuals did indeed remain in the greater region in the few pockets of remaining mature bottomland swamps. The last confirmed sighting in the United States occurred in 1944 in Louisiana. By the late 1900’s, it was generally assumed the Ivory-Billed was extinct.

The Ivory-Billed Woodpecker, however, recently jumped back into the public eye after a handful of credible, but not 100% confirmed, sightings from Louisiana, Arkansas, and Florida came to light in the early 2000’s. This raised the question as to whether the Ivory-Billed was truly extinct, or if tiny populations remained in remote and relatively untouched bottomland swamps around the Southeast. Sadly, even if the Ivory-Billed Woodpecker is not truly extinct, and a few individuals are indeed still alive in one or a handful of swamps around the Southeastern US, the species is still functionally extinct. Any such population—if one were to truly exist—would be too small to be viable over the long term.

Carolina Parakeet

Painting by John James Audubon, 1825, New York Historical Society.

The Carolina Parakeet was the second species to become extirpated from the I’On Swamp. The Carolina Parakeet—the only parrot species that was native to the Eastern US—was a denizen of mature swamps and forested floodplains filled with either American Sycamores or Bald-Cypresses. The Carolina Parakeet used to be quite common throughout the appropriate habitat in the 1700’s, but their populations began plummeting in the early 1800’s. The exact causes for the decline and ultimate extinction of the Carolina Parakeet are still debated, but most agree it was probably a combination of several factors. Habitat destruction via logging, unchecked hunting to attain their colorful feathers, unchecked hunting by farmers who viewed them as pests, and other factors all contributed to the decline and eventual demise of the Carolina Parakeet.

Carolina Parakeets living in the I’On Swamp probably began facing trouble in the late 1700’s, as the mature Bald-Cypress trees—whose cavities they nested in—throughout the swamp were cleared to make way for the rice plantation fields. When did they most likely disappear from the I’On Swamp? Although I can’t find any specific reports of this species from the swamp, I would say that the Carolina Parakeet was most likely extirpated from the I’On Swamp by 1810-1840 based on two details. First, many naturalists noted that Carolina Parakeet sightings were rarely made outside of Florida by the 1850’s, which suggests that most of the populations in South Carolina were probably gone by the early 1800’s. Second, most of the I’On Swamp was already intensely farmed for rice by 1820-1830, which means that most, if not all, of the appropriate Carolina Parakeet habitat was gone. No Carolina Parakeet habitat, no Carolina Parakeets.

By 1904, the last known wild individual was observed—and promptly killed. The year 1918 saw the death of the last captive individual. By 1939, the species was declared officially extinct, although tantalizing reports of Carolina Parakeets trickled in from Florida, Georgia and South Carolina between 1930 and 1960. The Santee Swamp was one site of such reports, with a handful of unconfirmed sightings of Carolina Parakeets inhabiting the dense, relatively untouched swamp were made throughout the 1930’s. If you remember, this is the same swamp which harbored Ivory-Billed Woodpeckers into the 1930’s, and is only 20 miles north of the I’On Swamp as well. Several credible people, such as bird wardens hired by the National Audubon Society, reported seeing Carolina Parakeets in the Santee Swamp, including on Wadmacon Island (the same island where the last confirmed Ivory-Billed Woodpecker in South Carolina was observed). Although these sightings were never confirmed, the existence of a small, remnant population of Carolina Parakeets existing into the 1930’s in the Santee Swamp seems plausible. Despite such thoughts, they are certainly extinct now.

Bachman’s Warbler

Painting by John James Audubon, 1833, Reynolda House: Museum of American Art.

The final species I want to discuss is perhaps the reason why the I’On Swamp is famous in the world of birders and naturalists. The I’On Swamp was the last known refuge for the Bachman’s Warbler. The Bachman’s (Pronounced “Back-Man’s”) Warbler was a small migrant songbird which bred in swamps throughout the Southeastern United States and overwintered in Cuba.

The Bachman’s Warbler was always a mysterious and hard-to-find species. It was first described by John James Audubon in 1833 when an individual was discovered in South Carolina. Over the next few decades, more individuals were recorded in other southern states, but the species seemingly disappeared from South Carolina. The Bachman’s Warbler was rediscovered in South Carolina by Arthur T. Wayne, a Victorian ornithologist, in 1901. The individual that Wayne found had been inhabiting the remnants of the Fairlawn Plantation, one of the old rice plantations found on the southern end of the I’On Swamp. As an aside, Arthur T. Wayne lived an absolutely fascinating life filled with ornithological endeavors. I highly recommend reading this short, 6-page biography on the man.

Wayne, who lived in the Charleston area, began systematically searching for more Bachman’s Warblers in the I’On Swamp, specifically throughout the old Fairlawn Plantation property. In 1906 he found two nests, providing evidence that the warbler did indeed breed in the I’On Swamp, and didn’t just use the swamp as a migration stopover. Over the next several years, he found many more individuals and nests.

As I said, the Bachman’s Warbler was always hard to find, and its ecology is rather misunderstood. There have been no actual studies ever done on this species prior to its extinction. Everything we know comes from naturalists in the 1800’s and early 1900’s who thankfully recorded bits and pieces of information on the species—whether it was the habitat one was found in, or the behavior of an individual, or what have you.

The last confirmed sighting of a Bachman’s Warbler was in 1988, and the species is almost certainly extinct. The cause for the extinction of the species has been subject to debate, and several hypotheses have been put forth about “the cause.” Nearly everyone agrees the Bachman’s Warbler went extinct due to habitat destruction, but no one knows what type of habitat the warbler exactly required. The Bachman’s Warbler vanished before any thorough studies of its habitat requirements could be conducted. The little habitat information we do have is confusing and contradictory, which further complicates matters. For example, some naturalists found the Bachman’s Warblers in mature swamp forests; others found it in young, successional swamp forests. If habitat destruction was the killer of the Bachman’s Warbler, what specific habitat feature was destroyed that the Bachman’s Warbler relied on?

Although Bachman’s Warblers had been recorded in mature swamp forests, it seems unlikely that they depended on such a habitat like the Ivory-Billed Woodpecker did. Between 1948 and 1953, there were many Bachman’s Warblers observed throughout the I’On Swamp, which—if you remember—was all but a young, secondary-growth swamp forest at that time after the period of intense logging between 1900-1920. The prevalence of the Bachman’s Warbler in the I’On Swamp when it was a young, secondary-growth swamp forest has made some scientists hypothesize that the species relied on disturbed, successional areas within swamps, similar to how the Blue-Winged Warbler and Prairie Warbler rely on similarly disturbed, successional areas within forests.

Drier areas within the I'On Swamp—like the area pictured above—would have been the site of extensive Giant Cane "canebrakes." Nowadays, such extensive canebrakes have vanished.

The apparent fact that Bachman’s Warblers could be found in both mature and successional swamp forests suggests that there was some other habitat component or feature that they relied on, and not simply the age of the forest. In 1986, J.V. Remsen Jr. published an article in the Auk that argued the Bachman’s Warbler was actually a bamboo specialist. Throughout the Southeastern US there’s a species of bamboo called Giant Cane (Arundinaria gigantea). Giant Cane used to be extremely prevalent throughout the swamps of the southeast, many times forming near-impenetrable understories called "canebrakes" which would go on for miles in swamps. Over the most recent 300 years, approximately 98% of these canebrakes were cut down or otherwise destroyed, as they proved a barrier to farmers and travelers. Sadly, Giant Cane is a finicky, slow-growing plant with a low reproduction rate, and the remaining individuals have been unable to fully recolonize the sites of former canebrakes. Although you can still find Giant Cane today, as well as dense canebrakes, these are nowhere near as dense and extensive as they once were.

What does that have to with the Bachman’s Warbler? As it turns out, most of the notes that naturalists recorded on the habitat of the Bachman’s Warbler mentioned the presence of Giant Cane. This is even more prevalent when reading descriptions of where nests were found; nearly all of them mention the nests being either in Giant Cane plants, or being in the same vicinity of Giant Cane. Many of their nests even contained leaves from Giant Cane. This suggests that the Bachman’s Warbler might have been a bamboo specialist, a niche that many birds across the world utilize. If this is true, then it makes sense that the Bachman’s Warbler disappeared as the Giant Cane canebrakes became less and less extensive throughout the Southeast.

Is the decline of Giant Cane the sole reason for the extinction of the Bachman’s Warbler? Probably not. Although it might be the main contributor to the destruction of the species, other factors probably exacerbated the decline. The destruction of swamps across the southeast, the destruction of their wintering habitats in Cuba, and potentially unknown factors might have all helped drive the Bachman’s Warbler to extinction.

The I’On Swamp Today  

Visiting the I’On Swamp today can be a difficult endeavor. The swamp is large, and only a few gravel and dirt roads allow access. Only one trail exists in the whole of the swamp. That trail—the 2.5 mile I’On Swamp Interpretive Trail—is part of the Francis Marion National Forest trail system. The I’On Swamp Interpretive Trail offers the easiest way for visitors to get “into” the swamp, but—at only 2.5 miles—it allows visitors a tiny glimpse of the swamp. Short of bushwhacking through the swamp, the trail is the best choice visitors have to see the swamp.

Nearly the entirety of the I’On Swamp Interpretive Trail runs atop ancient dikes that once belonged to the Wythewood Plantation, one of the main rice plantations that used to call the swamp home. As you walk along the nearly 300-year-old dikes, you can’t help but marvel at the engineering feat they represent. At the same time, you can’t help but feel an overwhelming sorrow when you realize that enslaved peoples from Africa were the ones who toiled away to make these extensive dikes. The colonial and early American rice industry was the second most dangerous industry for enslaved peoples to find themselves part of, second only to the sugar cane industry. Between the harsh owners, never-ending work, the oppressive heat of the Carolina Lowcountry, rampant diseases, and dangerous wildlife, being a rice plantation slave was an absolutely brutal, and many times short, affair. Injuries and deaths were commonplace. The mortality rate of enslaved peoples working on rice plantations is mind-numbing to consider. At some rice plantations, almost 90% of children died before they reached 16 years old. Many adults did not make it past 30. The profit margins on rice were so high that an enslaved person only had to work for one season for the owner to make back the cost of the slave, so slaves were viewed as a highly dispensable commodity. Although this mentality seems unfathomable today, it was sadly common throughout the Lowcountry in the 1700’s and 1800’s.

Today the I’On Swamp looks like a very young, secondary growth swamp forest. When Hurricane Hugo slammed South Carolina in 1989, the winds knocked down essentially all of the trees in the eastern section of Francis Marion NF, including the I'On Swamp. Consequently, most of the I'On Swamp's forest is only 28 years old. Despite the young age, the forest is still impressive. Dwarf Palmettos cover the ground. Red Maples and Black Tupelos take hold in the drier areas. Bald-Cypresses dot the wetter areas, where their knees jut up through the shallow, tannin-stained water. Alligators bask along the banks of the ancient dikes, and River Otters swim through the canals. The place feels natural on the surface, but—while it is still natural to a certain extent, true—the I’On Swamp is scarred. Animals which should call the swamp home are forever gone. Plants which should be easily found throughout the swamp are uncommon and nowhere near as extensive as they used to be. The water flows in unnatural channels and canals, separated by earthen banks that shouldn’t be there. The landscape has been forever changed, and a sorrow hangs in the air—not only because the land will never be as it once was, but also because so many lives were unnecessarily lost here.

Despite the scars, the I’On Swamp is nevertheless a fascinating place. Go visit the swamp if you’re in the Lowcountry of South Carolina. Walk along the ancient rice field dikes as you travel through the swamp forest. Look for animals and plants, and enjoy the landscape. But while you do, don’t forget to take a few moments to reflect on all the history bound up in this swamp.

Ross's Geese in Athens!

This February has shaped up to be one of the most spectacular migratory goose flights in Ohio in awhile. Beginning in the first week of the month, reports started pouring in from around the state on eBird, Birding Ohio, and other media reporting flocks of dozens to even hundreds of Snow Geese, Ross's Geese, and Greater White-Fronted Geese. These species of geese are pretty rare in Ohio, but each winter will often bring many scattered reports of one or two individuals mixed in with a flock of Canada Geese. The past 2 weeks, for some reason, has brought very large flocks of these rare geese throughout Ohio.

Luckily, Athens got to partake in what I've heard people calling "Goosapalooza." On February 12, Ohio University professor Phil Cantino reported 8 white geese on the western side of Athens near the Hocking River. These 8 white geese turned out to be Ross's Geese, and they continued hanging out for several days. Yesterday, on Feb. 15, a group of Ohio University students (including myself) went to see the individuals. It wasn't hard; we drove past a large group of Canada Geese hanging out at the Athens County Fairgrounds, and sure enough the 8 Ross's Geese were mixed in with the group of 150 or so Canada Geese.

The diminutive Ross's Goose is one of my favorite birds. As I mentioned previously, they are quite rare in Ohio, but they aren't globally rare, however. Their rarity in Ohio stems from their migration routes. The Ross's Goose breeds in northern Canada and overwinters in two distinct locations - California and the southern Great Plains. The populations which overwinter in the southern Great Plains migrate using the Central Flyway, which is pretty much 2 states west of Ohio. Since they utilize a migration flyway which doesn't come through Ohio, they don't really come through Ohio either. Occasionally something, whether it be a storm, individual mistake, etc., will cause one or a few individuals to veer off course and end up in places like Ohio. In the case of this giant flight into Ohio, weather is probably to blame.

Photo taken in Fairfield County, Ohio, back in December 2015. The Snow Goose is in the back, while the Ross's Goose is in front of the Snow Goose.

As you might have seen, I had a post on both Ross's Geese and Snow Geese back in December (which you can read at this link). The Snow Goose and the Ross's Goose superficially look the same, but there are a few differences to note. I'll use a nice comparison photo from the Fairfield County ones I chased back in December. In the photo above, the Snow Goose is the white goose in the back, while the Ross's Goose is the white goose in the front. First, take note of the black wingtips in both; this shows that the goose is either a Snow or Ross's goose, and not just a white domestic goose, which will lack any black in the wings. Now, how do you tell the difference between a Snow Goose and a Ross's? Essentially, a Ross's Goose is a miniature, duck-sized version of a Snow Goose. Size, however, can be deceiving. Another feature that can help, but can also be deceiving, is neck size; a Ross's Goose typically has a very short, stubby neck, while a Snow Goose typically has a much longer neck. However, this can be dependent on how the goose is holding its neck and it isn't a good feature to solely base an identification on. The best field mark to separate the two species is the bill. With a Snow Goose, the bill will be large and pretty long. The bill will also have a distinctive dark "mustache." A Ross's Goose will have a much smaller and more dainty bill, and it will lack that dark "mustache."

In the case of the flock of 8 white geese this time around, they were all tiny, short-necked geese with dainty bills. This identifies them all as Ross's Geese. This was pretty exciting; the Ross's Goose was one of the last rare goose species which I hadn't yet seen in Athens! When rare geese do show up in Ohio, it's typically in the northwestern part of Ohio or along Lake Erie. Southeastern Ohio isn't typically a hotspot for rare waterfowl. However, the past 2 winters have brought an array of rare geese, with Greater White-Fronted Geese and Cackling Geese and Snow Geese. Now I can add Ross's Geese to the list of interesting Hocking River visitors!

If you live in Ohio, keep your eyes out for the rest of the week for any unusual geese! You never know what you might find!

A Little Blue Heron in the Salt Marsh

As I mentioned in my previous post on the Cottonmouth, I recently took a 2000 mile solo road trip during my Winter Break. I spent most of my time birding throughout coastal South Carolina, racking up a total of 90 species (including 8 lifers) from December 28, 2015 to January 2, 2016. This wasn't my first time birding in South Carolina; just a few months prior I visited with my ornithology class for a 4 day field trip (which you can read about here: Part 1, and Part 2). It's an absolutely wonderful state to go birding in!

One of the locations I visited was Pinckney Island National Wildlife Refuge in the very, very southern tip of South Carolina. It's a very interesting preserve, and most of it is open saltwater or salt marsh. I went to visit a productive freshwater pond named the Ibis Pond, but first had to walk by an extremely shallow salt marsh. And in that marsh was a small white bird.

And that small white bird was a Little Blue Heron. You might be wondering why a "Little Blue Heron" is white, and this is because it is a juvenile Little Blue Heron. This species begins life in all-white plumage and individuals transition to their deep blue plumage upon maturity.

I would like to take a moment to talk a bit about the name "heron." As you might know, there are herons and egrets; both look essentially the same, aside from species-level color differences. You might be thinking there is some kind of difference between the two groups, like there's something that makes a heron a heron, and an egret an egret. I definitely thought that until I started my research for this post. Turns out, there is no significance to the names. Although the Little Blue Heron is called a heron, that name doesn't mean much in itself; in fact, the Little Blue Heron is most closely related to the Snowy Egret. So why the two groups of names? It's basically due to linguistic and societal differences. Birds in the family Ardeidae are called the herons. The name "heron," when talking about etymology (the study of a word's origin and history), comes from certain Germanic languages including Middle English. Egret, on the other hand, is still Germanic, but is based on the Old French word "aigrette," which is pronounced "egret." Aigrette can translate to "little white heron," but also refers to long, decorative plumes that certain heron species grow during breeding season. So basically, the French term "aigrette" was borrowed by English and morphed into "egret." This term was then applied to white herons, many of which also have those decorative plumes during their breeding season. However, when you look at the evolutionary history for these long-legged waders, you see that there's no biological basis for the differences in names; the birds we call egrets and the ones we call herons are all intermixed in various genera, and they don't break down into two completely separate groups. This is one of the many reasons why common names can be deceiving!

Back to the Little Blue Heron! This is a medium-sized heron species that stands about 2 feet tall. Here in the United States, Little Blue Herons are most commonly a resident of sub-tropical swamps and marshes in the southeast. However, like their cousin the Snowy Egret, the Little Blue Heron will also very sporadically breed in the northern half of the Eastern United States. Little Blues will also sometimes irrupt northward in the late summer after breeding is finished. When it comes to Ohio, the Little Blue Heron has an interesting history. A few pairs have actually nested in Ohio, and these pairs have been confined to the wading-bird nesting colony on West Sister Island in Lake Erie. These nesting individuals show up to forage in marshes throughout Ottawa and Lucas counties, including Ottawa National Wildlife Refuge and Magee Marsh. Even then, this is a very rare species to see in Ohio. To read more about the Little Blue Heron in Ohio, check out this link: OBBA Account

Although they are rare in Ohio, the Little Blue Heron is pretty common within their core range. They are typically a bit shyer than other herons, preferring to forage along the edges of wetlands either singly or in very small groups. The Little Blue is a stand-and-wait predator, meaning it prefers to quietly stand in one location and wait for prey to come to it instead of actively hunting them out. They typically feed on fish, amphibians, and crustaceans, but will also take insects and small mammals. This individual was in extremely shallow water (about 1 or so inches deep), and fish were nowhere to be found. I watched him as he slowly and carefully stalked about, turning his head to inspect the water for life. Eventually he struck the substrate and pulled up a bristle worm, as pictured above. Bristle worms, class Polychaeta, are a diverse group of mostly-marine segmented worms, and easy pickings for many wading birds.

While researching information for this post, I came across two very interesting studies that I would like to summarize. Both studies were done by Gloria S. Caldwell, and the papers can be found at this link: Caldwell 1981, Caldwell 1986. To give some background, most herons/egrets have the same plumage coloration throughout their life. The Little Blue Heron is a bit unusual in this as it is dimorphic in regard to age. The juveniles are white, while the adults are dark blue. Is there a significance to this color dimorphism? Turns out there is, and it’s incredibly interesting. Caldwell (1986) found that herons with white plumage were attacked by hawks more often than herons with "dark" plumage. At first glance, it seems that the juvenile plumage of the Little Blue would be a hindrance to survival, but it’s actually a bit more complicated than that. Caldwell also found that flocks of herons have a significantly lower chance to be preyed upon than an individual foraging alone, and this makes sense; the more eyes you have watching for predators, the less of a chance a predator will be able to commit a successful attack. How does this flocking feature factor in? Caldwell (1981) found that Snowy Egret flocks will more readily accept juvenile Little Blues than adult Little Blues (in fact, adults were attacked by the Snowy Egrets, while juveniles were left alone). Caldwell suggests that the white plumage of the juvenile Little Blues makes the Snowy Egrets, a white bird themselves, more apt to accept the juveniles than the dark-colored adults. So, although white juvenile Little Blues are more likely to be attacked by predators than the adults, they can mitigate this negative effect by foraging in a mixed flock with Snowy Egrets. In addition to all of this, Caldwell found that juvenile Little Blues actually had a higher success rate catching fish while in a flock than when they foraged alone.

Let me take a moment to sum everything up so far. Juvenile Little Blue Herons, which are white, are better accepted into mixed foraging flocks than the dark-colored adults. By being part of a flock, the juvenile Little Blues have a better chance to avoid predation. In addition, by being part of a flock, juvenile Little Blues have better success at catching fish. Therefore, by having a lower chance of being killed by a predator, and by being better-fed as they mature, a juvenile Little Blue Heron has a much better chance of making it to adulthood and passing on its genes. Having white plumage is, therefore, very beneficial, and natural selection ensures this white juvenile stage is maintained.

Now you might be wondering why there isn’t a selective pressure for the adults to be white, instead of dark blue, as well. There are some young white subadults that attempt to mate every year, and you would think those individuals would be heavily selected for, but those subadults almost always fail to mate. This implies there’s something else now at play, but what is it? It all has to do with breeding! As I mentioned previously, white herons are preyed upon at a higher rate than dark-colored herons. This is simply because white really stands out among the greens of swamps and marshes. To see this in action, look at the photo above; the white juvenile on the left stands out like a sore thumb, while the dark adult on the right blends in relatively well. Being inconspicuous is very important when it comes to nesting; nestling birds are incredibly easy pickings for predators as they can’t fly away and escape. Many predators know this, and many will actually watch for adults bringing food back to a nest in order to locate the nest. Once a predator knows where a nest is, and if they can get to it, then it’s all over for the nestlings. Because of this, adult birds try to hide the location of nests at all costs. If you are a conspicuous, attention-grabbing white, you might as well let predators waltz right up to your nest. By transitioning to a dark coloration upon maturity, Little Blue Herons reduce the chances that predators will attack them or their nest, which not only helps ensure their survival, but the survival of their nestlings as well.

In the end, natural selection selects for white-plumaged juveniles and dark-colored adults. By having this dimorphic coloration system, the Little Blue Heron optimizes survival across its entire life cycle from nestling to breeding adult.

That's it for this post! Thanks for reading!