This week for flora and fauna Friday we’ll be examining a pair of birds that are a familiar site along scenic highway 174. This week we’re talking about Vultures.
In South Carolina there are two species of Vulture, the Turkey Vulture (Cathartes aura) and the Black Vulture (Coragyps atratus). Both of our Vultures have dark plumage, featherless heads, great senses of smell and vision, and feed on dead animals. (On a side note, the term “Buzzard”, which is often applied to Vultures, is actually the name of several Old World Hawk species that will eat carrion but prefer to hunt prey.) Vultures lack feathers on their heads because of the nature of their diet. Feathers would get in the way of feeding on carrion and rot from continuous exposure to bodily fluids and bacteria. Thus, our Vultures have lost the feathers on their heads to avoid these complications. Vultures sun their dark feathers in the heat of the day for the same reason. This scorching heat serves to cook bacteria and parasites that cling to their plumage. Vultures, predictably, have extremely robust immune systems. It’s kind of a prerequisite if you’re eating rotten meat for a living. They are essentially immune to diseases like Anthrax, Salmonella, and Botulism! Vultures provide a valuable ecosystem service by eating carrion. By eating carcasses before they rot, Vultures help prevent the spread of disease and mitigate the localized disturbances to plant and invertebrate communities caused by decomposing animals. Adult Vultures, due to their unsavory lifestyle, have almost no natural predators.
Turkey Vultures can be distinguished from Black Vultures by their pink-red heads and legs, dark brown plumage, and more slender, raptor-like physique. On the wing, Turkey Vultures are readily identified by their gray primary and secondary feathers, rickety flight, and wings held upward in a dihedral aka a shallow “V”. Turkey Vultures get their name from their resemblance to the Wild Turkey. Both share a bald, pinkish head and dark brown plumage. The Turkey Vulture is a very efficient flier and can kettle high in the air for hours and miles on end, without flapping its wings once. They accomplish this by exploiting thermals and small scale turbulences along forest edges. Turkey Vultures have one of, if not the best, sense of smell of any terrestrial animal. They also have acute vision. This allows them to smell and locate carrion before any other scavenger can, all while circling high in the air. Turkey Vultures are often the first scavenger on a carcass and typically get to take their pick of the choice bits before their competition arrives.
Black Vultures can be separated from Turkey Vultures by their wrinkly gray heads and legs, black plumage, and a more robust, stork-like physique. Black Vultures only have gray primary feathers and their flat, forward-held wings and more direct powered flight style allows for an easy ID in flight. Black Vultures have eyes as equally keen as those of Turkey Vultures but have a less developed, although still impressive, sense of smell. Black Vultures are more energetic, boisterous, aggressive, and tend to travel in groups. Black Vultures have adapted to exploit these personality and physiological differences to their advantage. Black Vultures tend to circle higher in the sky than Turkey Vultures. From this vantage point they sniff and stare for carrion like any other Vulture but also watch for the lower flying Turkey Vultures. When they identify Turkey Vultures, or other Black Vultures, flying low over an area, they pursue the other birds in hopes of being led to a meal. This often results in Black Vultures swarming and stealing a carcass from the less aggressive and more solitary Turkey Vultures. This results in the common roadside spectacle of a dozen or two Black Vultures bounding, flapping, and encircling a roadkill. Black Vultures are also known to hunt some prey and will primarily target newborn or juvenile animals as a group.
Being a scavenger, Vultures are especially susceptible to threats from environmental contaminants. If an animal dies from poisoning or chemical contamination, a Vulture is likely to feed on its carcass and itself be poisoned. They also are at risk of gradual poisoning due to a concept called bioaccumulation. Bioaccumulation is where contaminants, such as heavy metals and pesticides, can accumulate in an animal overtime from eating contaminated food. These contaminants may not exist in this animal at dangerous levels but the predators that eat these contaminated animals will retain those same contaminants at an even higher concentration, so on and so forth up the food chain. This was the principle behind why DDT was devastating on carnivorous birds, like Eagles and Condors, but not their prey. As a carrion eater, Vultures sit at the peak of the food web and are especially susceptible to bioaccumulation. Although not as bad as the California Condor, our eastern Vultures took a hit from the widespread use of DDT. However, Vultures are one of the few animal species that have benefitted dramatically from human encroachment and habitat fragmentation from the construction of highway networks. This helped them quickly recover from the declines caused by DDT. Roadways are a huge source of mortality for many species of mammals. While bad for mammals this provides a smorgasbord of food for Vultures. The ribbons of asphalt through the woods create thermals and canopy opening that facilitate Vulture flight and their ability to see carcasses. In fact, the ranges of both the Black and Turkey Vultures are expanding northward because of this!
Once again for Flora and Fauna Friday, I’ll be writing in defense of a scorned and underappreciated genus of plant. This week I’m defending the honor of the genus Cirsium, the Thistles. We have two common Thistle species on Edisto: Yellow Thistle (Cirsium horridulum) and Nuttall’s Thistle (Cirsium nuttallii).
Thistles get a bad rap because they’re pokey and they make lawns and pastures look unkempt. But, a Thistle’s goal in life is not to assault the feet of barefoot meadow frolickers or the eyes of meticulous landscapers. Much like Sand Burs, they’re just trying to get by, undisturbed and uneaten, in a highly competitive habitat.
Thistles thrive in early successional habitat with a lot of disturbance. Succession and disturbance regimes are both doozies of ecological concepts that I’ll save for another time. For now, just know that the habitats they like don’t have many or any trees and some event regularly occurs that keeps the plant life in that condition. So these are places like roadsides, pastures, fields, lawns, savannas, and forest edges. Places where humans or nature keeps trees and shrubs out and the grass from becoming hay. Thistles do well here because they spend the majority of their life as something known as a basal rosette. A circle of leaves originating from a central point, laying directly on the surface of the ground above a ball of perennial roots. This keeps them low and out of harm’s way from things like snow, fire, and bushhogs. All while minimizing energy needs and shading out any grasses that might try to grow beneath its leaves, stealing its water and nutrients. Their stems and leaves, as I’m sure many of you are aware, are covered in hundreds of viciously sharp spines. These protect the plant from herbivores, like deer and rabbits.
When the time comes, thistles ascend from their basal rosette and form an inflorescence, or flower stalk. These flower stalks can be very large and are, predictably, covered in a profusion of little stabby bits. These flowers are unappealing to both lawn enthusiasts and would be herbivores but they are a huge draw for both Honeybees and native pollinators. Butterflies, bees, wasps, flies, and beetles swarm to these flowers for nectar and pollen. Especially the flowers of the large, early blooming Yellow Thistle. When the flowers have finished, Thistles produce scores of fluff tethered seeds that feed both Finches and Sparrows. These lint-linked seeds float on the breeze to new habitats with ease. If they, by chance, land in another open habitat, they can start the cycle anew. The parent plant is perennial and will come back each year until the habitat can no longer support it.
Yellow Thistles start producing flowers this time of year. Their flower stalks only reach about 3 feet in height but their stalks can be as big around as your forearm! Yellow Thistles get their name from their large, egg-sized, yellow-white flowers that are sheathed in a cage of spiny leaves. However, their flowers can also be pink or even magenta (like in the first photo below). This species is a great nectar and pollen source for pollinators emerging from their winter waiting.
Nuttall’s Thistles don’t bloom until the summer. Usually in two waves, one in July and one in September. Their flower stalks are pretty skinny but they can exceed 7 feet in height! The flowers of Nuttall’s Thistles are quite different from those of Yellow Thistle. They are much daintier, open, and showy. The flowers of this species range in color from white to hot pink. They appeal to a wide array of pollinators as well.
Thistles provide many benefits to our native pollinators, which in turn provide benefits to the local plant community as well as human agriculture. Next time you have a thistle spring up in your flower bed or front yard. Stay thy shovel and maybe you’ll reap the benefits of healthier wildlife habitat.
This week for Flora and Fauna Friday you’ll be getting a quick overview of an interesting family of songbirds. Diverse in shape, color, habitat, residency, diet, and rarity, this week we’re talking about the Thrushes, family Turdidae.
All of our Thrush are plump, medium to large sized songbirds. They all have big eyes, strong legs, a bill that is moderate in both length and heft, and an undulating, whistled, sing-song voice. All species primarily eat insects but will eat fruits in the winter months. There are 8 species of Thrush that can be seen in SC, including here on Edisto. Only 4 of those species are here for any significant length of time. The others just make pit stops in the state on their way to their breeding grounds in Canada.
The eight species of Thrush you can find in SC are: Eastern Bluebird (Sialia sialis), American Robin (Turdus migratorius), Wood Thrush (Hylocichla mustelina), Hermit Thrush (Catharus guttatus), Swainson’s Thrush (Catharus ustulatus), Veery (Catharus fuscescens), Gray-cheeked Thrush (Catharus minimus), and Bicknell’s Thrush (Catharus Bicknelli). Only the Bluebird, Robin, Wood Thrush, and Hermit Thrush are residents in SC. The Swainson’s Thrush, Veery, Gray-cheeked Thrush, and Bicknell’s Thrush can only be found in SC during their Spring or Fall migrations through the state.
I have short descriptions of each species attached to the photos below. The American Robin and Eastern Bluebird will get their own post eventually, so I won’t be going into much detail for any one species. I also don’t have a photo of a Bicknell’s Thrush, so I’ll append that description to the Gray-cheeked Thrush’s.
The Eastern Bluebird is a permanent resident of the state. They live in open fields, scrublands, lawns, and along forest edges where they nest in cavities and eat insects. Bluebirds are our smallest Thrush and easy to recognize by their blue plumage. Males are a brilliant blue and females a washed out blue to gray.
The American Robin is our largest Thrush and a permanent resident in some places, but mostly a winter visitor. They’re visitors of lawns, wetlands, and forest alike where they feed on insects and berries. Robins are easily identified by their rusty-red breast, black cap, and slate-gray back. Males are bolder in color and females a paler shade throughout.
The Wood Thrush is a summer resident in SC but aren’t common on the coast. They’re found in moist hardwood forests, especially along rivers. Their stockier body and bold, black-spotted breast sets them apart from our 5 Catharus Thrushes.
The Hermit Thrush is a regular and common winter resident of SC. You can find them in hardwood and mixed forests across the state. Their rusty rump and “tail pump” sets them apart from other members of Catharus.
The Swainson’s Thrush is a passage migrant found in woodlands. It has a flat brown plumage similar to a Hermit Thrush but lacks the rusty rump. It also has a golden wash to its cheeks.
The Veery is a passage migrant found in woodlands. It has an orange-brown back and faintly marked breast that make it easy to pick out from other Thrushes.
The Gray-cheeked Thrush is a passage migrant found in woodlands. Its plumage is a drab grayish brown that can make it tricky to identify. This species and the Bicknell’s Thrush used to be considered one species but are now separated. The Bicknell’s Thrush is a threatened species and VERY rare passage migrant that is nearly indistinguishable from the Gray-cheeked Thrush except by song.
This week for Flora and Fauna Friday, we’re zooming in on a genus of tiny wildflowers native to Edisto. This week we’re talking about Bluets, genus Houstonia. On Edisto I’ve seen two species of Bluet: the Tiny Bluet (Houstonia pusilla) and the Roundleaf Bluet (Houstonia procumbens). Both species are tiny, 4-petaled wildflowers that bloom in late winter and do well in open areas. Usually in rather poor soil. The Azure Bluet (Houstonia caerulea) can also be found in the area but I’ve yet to come across it on the Island.
The aptly named Tiny Bluet is only a few inches tall. It’s singular, yellow & mauve-eyed pale-purple flowers only measure about a quarter-inch wide. It’s thin, solo stems and dainty opposite and simple leaves pepper lawns, roadsides, and ditch edges with pinpricks of floral flare. Places with high disturbance, micro patches of bare-earth, and plenty of sun are their preferred locale. Their small stature lets them eke out a living in micro-habitats. These are tiny areas of habitat in a larger landscape that can are suitable for a given plant species. These micro-habitats can be a several yards across or only large enough to support a single plant. Whether they’re different in light intensity, soil moisture, available nutrients, or soil composition, micro-habitats are a patch of earth just different enough from all the other dirt around it to support a certain species.
The slightly larger Roundleaf Bluet is also only a few inches tall but a bit more robust. Their bone white petals encircle a lime green center to form a flower that’s about a half-inch wide. Their leaves are larger and wider, almost heart shaped. Unlike the Tiny Bluet, the Roundleaf Bluet will spread over the ground and tends to form mats a few inches across. Their wide leaves and spreading stems help them survive in the dry sandy habitats they prefer. Their large leaves and overlapping, spreading stems shade a significant area of the soil above its roots and help hold water in the soil where it would otherwise evaporate. These areas are naturally barren due to poor, dry soils but Roundleaf Bluet is adapted to exploit these barren sunny areas.
Like many of our spring wildflowers, Bluets are everywhere but often overlooked due to their size. However, in the right habitat, even a miniature wildflower like this can be a stunning sight. In certain sparse lawns and hayfields, the Tiny Bluet can create a purple haze above the ground. A thin film of violet hovering only a few inches above the grass, as millions of Bluet blooms rub shoulders with one another. Canada Toadflax is another that creates such a view. The sight truly a privileged experience to behold.
Before they start leaving for the season, this week for Flora and Fauna we’re going to be talking about our two winter Woodpeckers: the Northern Flicker (Colaptes auratus) and the Yellow-bellied Sapsucker (Sphyrapicus varius). Both of our winter Woodpeckers are unique compared to our other 6 non-migratory Woodpecker, in both their appearance, behavior, and diet.
The Northern Flicker is our second largest Woodpecker in SC, at about 12 inches tall. In the Eastern US we have the Yellow-shafted subspecies (C. a. auratus). Like most of our Woodpeckers, males and females are very similarly plumaged but differ in facial markings. Males have a black patch at the base of their bill and females do not (both of my photos below are females). The Yellow-shafted Flicker is a gorgeous bird. Instead of being monochrome with red accents, like the rest of our Woodpeckers, Flickers are an alloy of bronze, copper, steel, and gold with ashen whites, blackened coals, and a lone crimson ember. Look for the golden wings and tail feathers, speckled belly, black crescent on the chest, and red crescent on the back of the head.
Flickers are also unique in the way they feed. They primarily feed on the ground and not in trees. They hunt for insects in field, yards, and forest edges but also eat plenty of berries and other fruits in the winter. They are one of the few species that will eat the invasive Red Imported Fire Ant. They will attack ant mounts. Using their pointed bill to jab into the soil beside a mound before sticking out their long sticky tongue out to snatch ants, eggs, and larvae from their underground tunnels. They’re also one of the bird species I’ve seen eating the wax coated seeds of the invasive Chinese Tallow Tree.
The Yellow-bellied Sapsucker is an average sized sapsucker, at about 8 inches tall. They’re a more typically colored woodpecker, being mainly black and white with a touch of red on the head. Their plumage has a grungy, somewhat dirty quality to it compared to the rest of the Woodpeckers. They also have an amber wash to their belly, hence the first half of their common name. Both males and females have a red crown but males also have a red beard (my first photo is a male and the second a female).
Sapsuckers feed even more uniquely than the Flicker. They still stick to the treetops but instead of hunting for insects within the branches of trees, they peck rings of shallow holes around the trunks of trees called sap wells. They only peck down to the tree’s vascular tissue beneath the bark. They primarily target the phloem but will drill into the xylem on deciduous trees in the winter. The phloem is the area of the tree that carries the sugar rich sap generated in the leaves down to the roots. The xylem is the area of the tree that carries water and nutrients from the roots to the leaves but is often enriched with sugars in the winter as a natural antifreeze. Once exposed to the air and devoid of their protective bark, the phloem leaks this calorie rich sap into the sap well. The Yellow-bellied Sapsucker will regularly return to these holes to lap up this sugary syrup, hence the second half of its common name. They also won’t shy away from an easy meal of insects or spiders when available. The Northern Flicker and the Yellow-bellied Sapsucker are two of our more interesting and easy to identify Woodpeckers but they only visit us for half of the year. In the spring, both migrate north to feed and breed. They’re common yard birds but if you’d like to see one, they’ll only be on Edisto for another few weeks this season. So get out and look!
This week for Flora and Fauna Friday, I don’t have a species in particular but a group of plants instead. This week we’re glancing over some of our early spring wildflowers.
Wildflower is a catch-all term used to describe any herbaceous plant that produces a flower and grows freely in the wild. The species we’ll be taking a quick look at today are some of the earliest wildflowers to bloom every spring. These species are also tiny and incredibly abundant. They’re species you can look for in any lawn in the state. Just make sure you look closely. Except for Dandelions, the rest all have flowers less than a quarter inch wide! I was able to find each one blooming in the lawn beside the EIOLT office this morning. These early wildflowers provide a critical early nectar source for pollinators emerging after the winter as well as providing forage for herbivores like Deer.
These early wildflowers share some common characteristics. They grow fast, don’t grow very tall, produce lots of tiny flowers, and make seeds quickly. These species can only grow in the most open of habitats such as lawns, roadsides, and construction sites. Places where vegetation is routinely removed or the ground disturbed. Because of this high frequency of disturbance, these plants want to grow, flower, and seed as fast as possible before they get cut, crushed, or covered up. They also take advantage of the early spring to grow and flower immediately after winter before larger, longer lived wildflowers can establish. Many of the species I have below are introduced exotics. Florida Hedgenettle, for example, is a tuber forming perennial that is invasive in both ruderal and open forest communities. However, the rest of the exotics are not directly harmful to local ecosystems. They do displace and compete with native wildflowers for resources but are easily outcompeted by larger wildflowers later in the season.
Now grab your magnifying glass and your best macro camera and go find these first tiny embers of spring!
In order of appearance we have:
Henbit Deadnettle (Lamium amplexicaule) [exotic]
Slender Yellow Wood-Sorrell (Oxalis dillenii)
Common Chickweed (Stellaria media) [exotic]
Black Medick (Medicago lupulina) [exotic]
Canada Toadflax (Nuttallanthus canadensis)
Common Dandelion (Taxacarum officinale) [exotic]
Annual Rye (Poa Annua) [exotic]
Corn Speedwell (Veronica arvensis) [exotic]
Florida Hedgenettle (Stachys floridana) [exotic]
Pennsylvania Bittercress (Cardamine pensylvanica)
Tiny Bluet (Houstonia pusilla)
Annual Blue-eyed Grass (Sisyrinchium rosulatum)
INDIVIDUAL DESCRIPTIONS
Henbit Deadnettle (Lamium amplexicaule), an exotic member of the mint family, Lamiaceae.
Slender Yellow Wood-Sorrell (Oxalis dillenii), a native member of the Woodsorrel family, Oxalidaceae. Their leaves may look very similar to those of the Clovers, but they’re completely unrelated.
Common Chickweed (Stellaria media), an exotic member of the Pink family, Caryophyllaceae.
Black Medick (Medicago lupulina), an exotic member of the legume family, Fabaceae.
Canada Toadflax (Nuttallanthus canadensis), a native member of the Plantain family, Plantaginaceae. Not the culinary Plantain, which is a species of Banana, but the botanical Plantains.
Common Dandelion (Taxacarum officinale), an exotic member of the Sunflower family, Asteraceae.
Annual Rye (Poa annua), an exotic member of the grass family. It’s a close relative of Kentucky Bluegrass, a common turfgrass.
Corn Speedwell (Veronica arvensis), another exotic member of the Plantain family, Plantaginaceae.
Florida Hedgenettle (Stachys floridana), an invasive exotic member of the Mint family, Lamiaceae. Florida Hedgenettle is an invasive species that can outcompete native wildflowers for resources. It’s a perennial that forms an underground tuber. Which it regenerates from in the spring. You’ve probably seen these strange looking tubers before. They’re about the size and shape of your thumb, white, and look like oversized maggots. (Or maybe the Michelin Man’s lost pinky)
Pennsylvania Bittercress (Cardamine pensylvanica), a native member of the Mustard family, Brassicaceae. (And yes, the specific epithet is supposed to be misspelled)
Tiny Bluet (Houstonia pusilla), a native member of the Bedstraw family, Rubiaceae. (I may be writing a full post about this genus of tiny flowers in the coming weeks) Annual Blue-eyed Grass (Sisyrinchium rosulatum), a native member of the Iris family, Iridaceae. (I’ll certainly be writing a full post about this genus in the coming weeks)
This week for Flora and Fauna Friday we’re talking about the American Goldfinch (Spinus tristis).
The American Goldfinch is the smallest of the four Finch species that visit Edisto. Their petite stature, golden plumage, and pink legs distinguish them from the drab by comparison Pine Siskin, House Finch, and Purple Finch. Additionally, their heavy bill makes them easy to pick out amongst our many small yellow Warblers. Male Goldfinches sport a rich, sunflower yellow plumage accented by a black cap over beady black eyes, an orange bill, pink legs, white rump, and black wings and tail streaked with ribbons of white. Females lack the black cap and are a drab grayish-yellow in winter but sport monochrome wings and tail throughout the year.
Goldfinches make many sounds throughout the day. High pitched bursts of whistles, mewing, and undulating squeals, distinctly separate or mushed together into a sweet, chaotic mess of a song. These birds tend to travel in flocks where these tangled strands of song intertwine and weave together into a cacophonous flowing fabric of notes that flutters over the forests and fields. Goldfinches are found in South Carolina year-round but are much more abundant in the winter. Birds from northern states migrate south to avoid the cold, while southern birds tend to stay close to home. Their stout bill is great for hulling seeds, their food of choice. Goldfinches mainly stick to the treetops in our area, where they feed on the seeds of trees like Pines, Sweetgums, and Tulip-Trees. They’re also partial to eating the seeds of large wildflowers like Thistles, Sunflowers, Coneflowers, and many Grasses. A walk through the wintery woods and savannas of the Lowcountry, with an ear cocked to the treetops, is an easy way to find a flock of Goldfinches. Goldfinches will visit bird feeders and wildflower gardens from time to time. Putting out a thistle feeder or a birdseed mix with thistle and safflower seeds in the winter can entice Goldfinches to visit your yard. Maintaining a wildflower garden planted with Zinnias, Mexican Sunflowers, Black-eyed-Susans, Coneflowers, Swamp Sunflowers, Thistles, Cornflowers, and other tall wildflowers will not only attract Goldfinches year round but also other songbirds like Painted Buntings, Grosbeaks, Cardinals, Sparrows, and House Finches as well as butterflies and other native pollinators.
This week for Flora and Fauna Friday, I’m presenting an introduction to animal tracks.
The winter can be boring for a naturalist, especially if stalking ducks or chasing shorebirds isn’t your cup of tea. As trees lose their leaves, annuals dry up, perennials die back to their roots, reptiles and amphibians hibernate, and the birds quiet down, it becomes much harder for naturalists to find wildlife in the winter months. However, winter is an opportune time to look for animal tracks. As plants stop growing for the winter and take in much less water from the soil, leaving the ground soft and soggy. Annuals die off for the year, exposing bare soil. Mammals have to search more to find food, so they travel further than normal and farther from the beaten path. Most mammals are nocturnal, so the longer nights give them more time to forage. If it snows, that just means an animal will leave tracks everywhere it goes. All these factors improve both the quality and quantity of animal tracks found in the winter and create a perfect environment for a naturalist to see just how many and what types of mammals surround them throughout the year.
Below I have a sample of most of the common species you’ll find tracks for on Edisto. Try and see how many you can identify! I have the species and track characteristics for each photo in the descriptions.
What exactly is an animal “Track”?
Tracks are the physical impressions an animal makes in the substrate, the material the ground is made of, as it moves through its environment. Tracks are predominantly footprints but, for example, also include things like tails drags for Alligators. Tracks are not to be confused with “Signs”, which are any other environmental indication of an animal’s presence. Signs include things like: trails, scat, slides, burrows, holes, rubs, scrapes, chew marks, etc. Signs are equally useful in identification but, with the exception of droppings, signs are typically found under unique circumstances and in specific locations. Since most signs are subtle in nature and unique for certain types of animals, I’ll just be talking about tracks today.
Now, where can one find tracks?
In my experience dirt roads, marsh flats, nature trails, point bars, and the banks of ocean inlets are the best places to find tracks. However, any place with lots of bare earth and soft soil is a good bet. If you follow Deer and Raccoon trails, which many other species use, sooner or later you’ll find a depression or patch of dirt where tracks are present.
What species can you expect to find tracks for?
That all depends on the type of substrate you’re dealing with and the habitat you’re in. If you’re dealing with dew dampened sand on an island driveway, it’ll hold tracks for everything between a Horse and a Dung Beetle. However, dry, hard-packed clay on a causeway may not even take deer tracks unless there was a torrential rain the day beforehand. For the most part, you’ll only see tracks for animals the size of a Squirrel or larger. As far as habitats go, typically you see more tracks where animals tend to gather. The edges of wetlands, marshes, and fields act as natural borders that mammals follow. Open areas on causeways and dikes act as bridges for Mink, Raccoons, Otters, Alligators, and Turtles to pass between wetlands. Carnivores like to hunt on the edges of heavy brush where Deer, Rabbits, and Turkeys retreat during the day. Birdfeeders attract Squirrels, Rats, Raccoons, and Deer looking for an easy meal. After them may come predators like Bobcats, Coyotes, Foxes, or Mink. Armadillos and Opossums may show up as well to eat invertebrates in the feeder spill or by following an established trail. Mammals are by far the most common and easiest to identify tracks. Turkeys and Alligators are also quite common and easy to distinguish. You can expect to find Raccoon, Deer, and Armadillo tracks anywhere you look.
How do you identify tracks?
Identifying tracks successfully requires having a good understanding of the body shape, behavior, and lifestyle of the animals that make them. Some species, like the Nine-banded Armadillo and Virginia Opossum, leave tracks so distinct they can’t be mistaken for anything else. Others, like Bobcats and Feral Cats or Coyotes and Hound Dogs, require a good deal of investigation to tell apart. The important features to look at in tracks are size, depth, gait, and the shape and arrangement of the individual parts of the foot that left impressions. The size of the track tells you exactly how big the foot of the animal that made it was. This is very important in telling Canids apart. Depth gives you an estimate of how heavy the animal was and the force with which the animal landed. Gait tells you the length of the animal’s stride and whether it was walking, trotting, or sprinting. The shape and arrangement of the track itself is the most important feature in identification. The shape and location of the heel, toes, and nails is unique for almost every mammal species in our area. I get into the specifics for each species in the descriptions of the photos below.
Now get out there are see who’s been hanging out in your backyard when you weren’t looking!
PHOTO DESCRIPTIONS
1. American Mink
The tracks of the American Mink are consistently circular in appearance with five toe pads and claw marks. They are almost always found near wetlands.
The Mink is one of our more confusing track makers. All the tracks in this photo are from a Mink. The Mink is a highly agile animal that has quite chaotic movements. This necessitates that they vary the shape of their feet to provide the best traction possible for their current gait and the surface they’re moving on. This results in highly variable tracks, with a hard to decipher gait, that crisscrosses over top of itself. The Mink’s tracks are most easily confused with those of the Common Raccoon, as well as the Bobcat and North American River Otter. Otter Tracks are very similar in shape but are far larger, about the size of your palm. The walking tracks of the Mink look a lot like a Bobcats but Mink have a fifth toe, consistent claw marks, and a larger foot. Raccoons are the most similar in size but their hand-like feet leave prints with elongated toes that are strongly connected to the heel and claw marks that blend into the tip of the toes. Raccoon Tracks are typically more triangular in shape than circular.
2. White-tailed Deer
The Tracks of the White-tailed Deer, along with the Common Raccoon, are the most common tracks you’ll encounter in the Lowcountry. Deer tracks consist of two tapered, mirrored hoof prints and occasionally an additional set of tiny rear hoof marks, especially from mature bucks. Deer heavily utilize trails and are fond of walking along dirt roads. So if you follow one long enough, you’re bound to find some tracks.
Excluding livestock, there’s only one other species that has tracks resembling the White-tailed Deer, the Feral Hog. The hooves of Feral Hogs are not tapered like those of Deer, so they leave a set of mirrored semi-circles. This gives the prints of a Deer a heart or crab-claw shape and the Feral Hog that of a rounded rectangle. The rear hoof prints of a Hog are also typically larger and farther to the outside.
3. American Alligator
The tracks of the American Alligator are hard to mistake. Alligators produce the largest tracks of any of our wildlife. Look for handprint shaped tracks that can exceed a foot in length with long toes, claw marks, and usually accompanied by a tail drag.
4. Marsh Rabbit
The tracks of Marsh Rabbits are basically identical to those of the Eastern Cottontail, but the latter rarely ever ventures onto marsh flats. I’ll just be talking about Rabbit tracks in general here. Rabbits have pointed, asymmetrical, 4-toed tracks. The gait of Rabbits is distinct. Their bounding movements leave all of their tracks bunched together with the front feet landing one in front of the other and their rear feet landing directly across from each other, outside of the front prints. The further forward the rear prints are in relation to the front prints, the faster the Rabbit was moving.
The most similar tracks to those of Rabbits are Squirrels but only in gait. Squirrels also travel in a bounding motion but they have 5 rear toes, symmetrical front feet, and thinner, more hand shaped prints. Squirrels never venture into the salt marsh, where Marsh Rabbits live.
5. Common Raccoon
Raccoon tracks are incredibly common. They have 5 toes on both feet, with the rear heel being markedly larger than the front. The tracks are hand shaped with the toes having a weak claw and strong connection to the heel. Raccoons like washing their food, so look for their tracks anywhere there’s standing water, especially in pluff mud.
6. Coyote
Coyote tracks are symmetrical with 4 toes and distinct claw marks. They’re typically 3 to 4 inches long. Coyote tracks are very similar to those of the Domestic Dog but there are some distinctions that can help tell the two apart. Dogs, especially retrievers, have larger, wider feet. Dogs are also typically much heavier than Coyotes, who rarely exceed 40lbs. For their weight, Coyotes have large feet. This makes their tracks rather shallow, and narrow, with little claw showing. Coyote tracks are compact and oval in shape. Dogs are much bulkier, so their feet splay out and they use more claw for traction. This gives Dog tracks a circular shape and their toes spread further apart and have prominent claw marks. Foxes have similar tracks to Coyotes but the tracks are smaller in size and have a slight gap between the front and rear toes.
7. North American River Otter
River Otter tracks are large, have five toes, obvious claw marks, a long rear heel, and occasionally a tail drag. Otter tracks are always near water. Look for their tracks on causeways and dikes around water control structures. They resemble Mink tracks but are much larger, with front tracks up to 4 inches in length. Their chaotic, weaselly gait and playful social nature means their tracks are often a mess of several individuals bouncing and rolling around in an area.
8. Wild Turkey
Turkey tracks are the one bird track you can reliably identify. They have large 3- toed tracks, a prominent heel dot, and a relatively small rear toe and claw mark. Their tracks are usually about 6 inches in length. The only other bird that commonly leaves tracks this large is the Great Blue Heron. The Turkey is significantly heavier than any Heron; this means Turkey toes are much wider. Herons have longer tracks with a prominent rear toe.
9. Bobcat
Bobcat tracks are asymmetrical with four toes and no claw marks. In the Southeast, their tracks are practically identical to those of Domestic and Feral Cats. There’s no easy way to tell the two apart but their gait can be telling. Bobcats are taller and longer than Feral Cats, so their stride is longer. Bobcats also travel longer distances in search of prey than do Feral Cats. So, if you have a good enough trail, you can make a good guess about the size of that cat and how far it went. The track above is two prints on top of each other. They came from a Bobcat who I tracked after this recent snowfall. I followed her trotting tracks for over a mile through the snow.
10. Nine-banded Armadillo
The Nine-banded Armadillo has a track like no other in our area. Typically, their front track is two toe/claw marks and their rear three but occasionally they have 4 and 5 respectively. Like a lot of four-legged mammals, when walking Armadillos move both legs on one side of the body at once, placing the rear foot in front of where the front foot just was. This creates a strange looking “5-toed” track, like in the picture above, with 3 toes in front and 2 in back but in reality it’s two tracks, one ahead of the other.
11. Virginia Opossum
The Virginia Opossum is another mammal with an unmistakable set of tracks. I rarely see their tracks but there’s no question about who made them when I do. Opossum tracks have five toes on both feet and the front and back feet are very differently shaped. The front track is shaped like a stubby, wide open handprint and the rear track like a closed hand with a thumb that points in almost the opposite direction from the fingers. The photos above are in snow, so it’s a bit difficult to make out the fingers. These wonky feet are built for climbing trees. Their wide grip allows them to easily scale trees and walk along branches.
This week for Flora and Fauna Friday, we’re looking at a pair of birds that we welcome to our state every winter, the Kinglets.
There are two species of Kinglet that migrate to our state: the Ruby-crowned Kinglet (Regulus calendula) and the Golden-crowned Kinglet (Regulus satrapa). Kinglets are tiny birds. The only SC bird smaller than a Kinglet is the Ruby-throated Hummingbird. Despite their size, Kinglets have a lot of energy and personality. Kinglets spend their days rapidly bouncing through the brush or treetops eating tiny caterpillars, moths, spiders, beetles, and other insects that are overlooked by larger leaf gleaners. Count yourself lucky if you get to watch one sitting still for longer than 3 seconds. Their small size and preference for cold weather means they need to eat constantly to keep their metabolism up and avoid hypothermia. Kinglets, especially the Ruby-crowned, are gregarious and boisterous. Ruby-crowned Kinglets often make a chattering call, much like a Wren, as they dart through brush or along forest edges. They sing a chaotic song, featuring a rapid build-up into a series of sporadic whistles, squeaks and chirps that is, once again, very Wren-like. Golden-crowned Kinglets are more reserved, issuing high pitched calls and songs from the treetops, reminiscent of a Chickadee.
The Kinglets get their name from their diminutive size and a vibrantly colored crest. Males of both species flaunt this normally subdued crest in courtship and territorial displays. As their common names imply, the Ruby-crowned Kinglet has a striking ruby-red crown and the Golden-crowned Kinglet has a fiery golden-orange crest. Apart from their hairstyles, the two species are easy to tell apart. Ruby-crowned Kinglets prefer habitat low to the ground and are most commonly seen flitting through shrubs along forest edges or in forest understories. They are olive-drab in color with an unmarked face, save for a prominent white eye-ring. Golden-crowned Kinglets are partial to the canopies of Pines, particularly in mixed forests. Their bodies are similar in plumage to Ruby-crowned Kinglets but with a pale-gray underside and a more petite build. Their face, however, is much different. They sport a sooty moustache and eye-stripe as well as a halo of coal beneath their burning crown. Kinglets are birds that are easy to find but hard to see, and even harder to photograph (evidenced by my lackluster photos). Kinglets are common visitors to backyards, so long as you have the vegetation for them to hunt in, but their tiny size and hyperactive nature let them hide in plain sight. Next time you find yourself on the forest’s edge in the cool morning air. Take a minute to listen for chatters and whistles while watching for tiny green blurs. You may just stumble upon a Kinglet, collecting its breakfast.
This week we’re looking at a misunderstood but ecologically important species. This week we’re talking about the Hispid Cotton Rat (Sigmodon hispidus).
The Hispid Cotton Rat is one of our three native species of Rat here in the Lowcountry. The other two are the Marsh Rice Rat (Oryzomys palustris) and Eastern Woodrat (Neotoma floridana). We also have two exotic species of Rat: the Roof/Black Rat (Rattus rattus) and the Norway/Brown Rat (Rattus norvegicus). Cotton Rats are a common mammal found throughout the state. However, they are nocturnal and live in heavy vegetation. So they’re not often seen. They inhabit grasslands, particularly: savannas, fallow fields, hayfields, salt marsh edges, and meadows.
Let’s take a look at its names to see what we can learn about them. Hispid is a term that means “covered in bristles”, which is appropriate for this rodent that’s covered in coarse fur. They get the name “Cotton Rat” from their historic abundance in cotton fields and for using balls of cotton in their nests. For the scientific name, we see the term hispid again for the specific epithet. The genus Sigmodon translates directly to “Sigma-shaped tooth” or “S-shaped tooth”. This describes the shape of their molars, which have a chewing surface that is serpentine in shape. So “Stiff-haired S-Tooth” would be an accurate translation.
These S-shaped molars are important to their diet. Hispid Cotton Rats are primarily herbivorous, eating mostly the vegetation of grasses and forbs as well as seeds and occasionally insects. Plants, particularly grasses, are difficult to digest and must be chewed more thoroughly in order to be properly digested. This requires these large, flat grinding teeth to do. The stiff fur of the Cotton Rat is also important to its lifestyle. Their stiff fur pushes out against the heavy vegetation they live within and protects their skin from sharp-edged grasses and blackberry vines.
Cotton Rats are a crucial link in the food webs of grassland ecosystems. They are a primary food source of nocturnal and crepuscular predators like Owls, Bobcats, Foxes, Coyotes, Rattlesnakes, and Mink as well as diurnal predators like Harriers, Hawks, and Rat Snakes. They also help to influence the plant community by eating the seeds and shoots of grasses, allowing for openings in the understory where less dominant plant species can establish. This in turn can improve forage for other mammals and birds as well as increase insect and pollinator diversity. Cotton Rats are not a species that inhabits human dwellings. In fact, none of our native Rats do. They may visit your bird feeder or barn at night but they’re gone by morning. They all have their own preferred habitats and nesting sites. Cotton Rats live in fields and make nests under dense grass. Rice Rats live in marshes and build nests in brush on the wetland’s edge. Woodrats live in forests and build their nest from sticks at the base of a tree or shrub. Our native Rats are important parts of the ecosystems around us and should be treated with respect and courtesy, like any other wildlife species. However, the exotic Roof and Norway Rats do not deserve such courtesies. These are the Rats that invade homes, spread disease, destroy farm equipment, contaminate livestock feed, attack pets, kill threatened and endangered wildlife, and destroy native plant communities. They have earned the spite of man and deserve no quarter on this continent. This is why I never recommend relocating Rats caught in live traps. Native Rats typically don’t need relocating and it is grossly irresponsible to release exotic Rats into new habitats. Learn to identify exotic Rats and help save our wildlife.
