Category: Phinizy Blog Feed

Question Mark Butterfly

Question Mark Butterfly
By Damon Mullis

This Question Mark Butterfly (winter form) was photographed in the park in February by Larry Anderson.

This Question Mark Butterfly (winter form) was photographed in the park in February by L. Anderson.

Spring is in full bloom, and with it butterfly activity in the swamp is on the rise. To prime you for butterfly season, today we’ll explore a butterfly that sometimes gets overlooked while people are out searching for Monarchs and Swallow-tails: the Question Mark Butterfly (Polygonia interrogationis). It gets its name from the silver question mark-like marking seen when its wings are folded back. In this position, the butterfly looks remarkably like an old leaf, disguising its location from predators.

The Question Mark larvae are more opportunistic feeders than many other butterfly larvae. Unlike Monarch larvae that only feed on milkweed, they feed on many different plant species, with elm trees and nettles being some of their favorites. Interestingly, the adult females usually lay their eggs under the leaves of non-host plants and the hatchlings must search out a suitable plant species to feed on.

There are usually two generations of hatchlings per year with each brood having a different adult form. The upper hindwing surfaces of the summer form are largely black. The upper wing surfaces of the winter form are fringed with violet, and the hindwings are rich orange above. As adults, they like to feed on fermenting fruit, tree sap, dung, and carrion, and only feed on nectar if these sources aren’t available. In addition to Question Marks, many other butterfly species feed on a variety of non-nectar food sources. So, when you’re out searching for butterflies in the park, don’t just focus on the flowers.

Osprey Nesting at Phinizy Swamp Nature Park

IMG_2714The Osprey is considered a common bird of the coastal plain. But over ten years ago, when we discovered a pair nesting at the Swamp, we were overjoyed! Their nest, however, was a long way off in the distance and only visible from the 3-Ton Bridge – with a scope. For many years this was our only visible active nest. In 2012, we were surprised to see construction of a new nest on the Wind Shear Tower, the tall pole out in the middle of the constructed wetlands. This new nest site was not only ideal for the Osprey, but highly visible for all onlookers! The first eggs were laid in March 2013 and everyone anticipated an exciting year with very close views of the nesting pair. Unfortunately, shortly after, a flock of crows raided the nest and no eggs hatched. But the Osprey pair didn’t give up. In 2014, the Osprey returned and successfully raised a brood with at least two young in the wind shear tower nest.

IMG_3128We are so excited to announce that this year the Osprey are back! Keeping a close eye on the nest, we were able to determine that the first egg was laid sometime between March 11 and 18, 2015. With an incubation period of 32 to 43 days, the first chick is due to arrive any day now! Osprey young hatch asynchronously – meaning at different times, so the first chick might be a week or two ahead of the other nestlings. If the food supply is limited, the last hatchling doesn’t get fed – a rather harsh reality in the natural world. Three Osprey chicks require about 6 pounds of fish per day. This makes the wind shear tower an ideal nesting spot. Not only is it the highest spot around, but there is an abundant supply of fish in the surrounding constructed wetlands.

IMG_0619Osprey populations crashed between 1950 and 1970 due to exposure to DDT. Today their populations have recovered thanks to conservation efforts, and the fact that Osprey have adapted very well to living in a populated human environment. They readily use artificial platforms, power line poles and other towers like our own Wind Shear Tower for nesting and feeding.

Come welcome our newest residents and join us in watching their development!

Phinizy Researchers to Study Savannah River Oxbow Lakes

Phinizy Researchers to Study Savannah River Oxbow Lakes

By: Dr. Oscar Flite, III

In order to make sure there is enough water to support a healthy river ecology and thriving economies along the Savannah River, water resource managers are always in need of high-quality information that will allow them to make better decisions so they can provide the balance between ecology and economy.  This spring, Phinizy Center scientists will begin a study to  examine the impact of various flows on the aquatic life in oxbow lakes found along the Savannah River downstream of Augusta.

Oxbow lakes are remnant sections of river channels that have been cut off from the main river flow. These remnant sections are created naturally in lowland rivers as a result of erosional processes where a narrow strip of land is surrounded by water on three sides.  Over time, the river erodes both sides of the land creating a short cut and leaving a section of old river channel. This channel or oxbow is initially connected to the river via surface water but over time can become disconnected and filled as a  result of sediment transport and deposition.

Shown here, an oxbow lake (left) and soon-to-be-oxbow lake. Oxbow lakes are remnant sections of river channels that have been cut off from the main river flow. (Courtesy photos)

Shown here, an oxbow lake (left) and soon-to-be-oxbow lake. Oxbow lakes are remnant sections of river channels that have been cut off from the main river flow. (Courtesy photos)

Research on oxbows around the world has revealed their important role in supporting healthy rivers. Studies have shown many more algal, zooplankton, mussel and fish species live in oxbows compared to the adjacent river.  Other studies have indicated that oxbow lakes are essential to the health of the river fisheries, providing abundant food resources and essential nursery habitat for juvenile fish.

In an effort to straighten and shorten the Savannah River for commercial navigation, the Army Corps of Engineers created many oxbows by cutting through wide river meanders.  These short cuts were generally developed in curved areas of river that were too sharp for boats to navigate. The short cuts were created by dredging a new river channel through a small strip of land that the river ran along both sides of, much like the natural oxbow creation process. From the 1950s to the 1970s, a total of 37 navigation short-cuts were completed, shortening the Savannah River by about 40 miles.

The oxbow research will involve several components.  First, scientists will assess the connectedness of many of the oxbows between Augusta and Savannah using high-accuracy GPS survey equipment.  Next, they will monitor surface and groundwater levels in four oxbows, two that are still connected to the river by surface water, and two that are disconnected.  Then, Phinizy scientists will monitor water quality and analyze water samples for nutrient, algae, and zooplankton levels.  Lastly, the researchers will periodically examine the fish communities in these oxbows.  Perhaps most interestingly, some fish in one connected oxbow will be outfitted with tiny radio tags that will allow researchers to monitor their movements between the river and the oxbow.

Phinizy Center scientist will perform this oxbow research in collaboration with scientists from Clemson University, Georgia Regents University, and Georgia Southern University.  The project is being funded by a competitive statewide research competition offered through the South Carolina Water Resources Center at Clemson University; the project will last for one year.  Results from this research will be presented at the South Carolina Water Resources Conference and communicated via Phinizy Center’s web and social media sites.


Spotted: Winter Mosquito

Culiseta inornata female courtesy of Treasure Tolliver and Nathan D. Burkett-Cadena.

Culiseta inornata female courtesy of Treasure Tolliver and Nathan D. Burkett-Cadena.

Culiseta inornata female caught by Phinizy Center.

Culiseta inornata female caught by Phinizy Center.

Spotted: “Winter Mosquito”

By: Kelsey Laymon

Culiseta inornata is a species of mosquito uncommonly found in the Georgia area. However, this past week Phinizy Center Researchers were lucky enough to find two of these mosquitoes! They are easily identified by their black and white speckled scales on the edges of their wings and a hairlike “setae” found on the base of the wings. Fortunately for humans, these mosquitoes prefer to feed on deer, cows and horses. This particular species prefers to breed in pools, ditches and sometimes artificial water containers. They were found during early March, and typically are active during the winter; giving them the nickname “Winter Mosquito.”

Breathing Underwater

Breathing Underwater
By Jason Moak

Researchers at Phinizy Center monitor the oxygen levels in the Savannah and Ogeechee Rivers to better understand how they function and ensure the health of aquatic organisms that live there. Most of us know that oxygen is one of the essential requirements for human life. Oxygen in our bodies is a vital component of many life-sustaining chemicals and processes. The same is also true for most organisms that live in our lakes, rivers, and streams. Just as we humans depend on the oxygen present in the air we breathe, aquatic organisms depend on the oxygen present in the water they “breathe.” As those organisms breathe, they use up the oxygen in the water and it must be replenished. But how?

WaterOverDamOne source of oxygen in water is diffusion from the atmosphere. Based on the laws of physics, there is a maximum amount of oxygen that water can contain. To understand this, imagine if you were to add a couple of tablespoons of sugar to water and stir. After some time, the sugar granules would dissolve in the water. You could add a couple more tablespoons of sugar and stir and the sugar would again dissolve in the water. At some point, though, once the water becomes full or saturated, the sugar you keep adding would no longer dissolve. The same holds true for how much oxygen can be dissolved in water. If water does not contain the maximum amount of oxygen it can hold (it is undersaturated), then oxygen present in the air above the water can dissolve or diffuse into the water, just like the sugar. This diffusion process is pretty slow, but it can be sped up by turbulence, such as when water falls over a dam or passes through steep, rocky sections of a river or stream.



The other source of oxygen in water is photosynthesis. On land, plants absorb the energy from the sun and carbon dioxide from the atmosphere, use them to grow, and put out oxygen as a byproduct. Similarly, organisms like algae and phytoplankton that live in the water emit oxygen into the water during the day as they grow. Sometimes, these photosynthetic aquatic organisms can be so productive that they actually supersaturate the water with oxygen. When this happens, there are only two ways for that extra oxygen to get out of the water: diffusion (also called off-gassing), or respiration. Diffusion in this case is simply the reverse of what was described above, except here the excess oxygen dissolves from the water into the atmosphere. The other process, respiration, occurs when aquatic organisms like fish or bacteria “breathe” in the oxygen in the water using it for their own growth.

Oxygen Meter

Oxygen Meter

Based on state and federal laws, the waters in our local rivers and streams are required to have a daily average of at least 5 milligrams per liter of dissolved oxygen to ensure that they remain healthy. If you are interested in the dissolved oxygen levels of the places Phinizy Center monitors, check out our website at

Southern Naiad: another native plant

Southern Naiad: another native plant

By Priscilla Hollingsworth

I was leaning over the boardwalk last week, and I spotted a plant in the main Butler Creek stream that I had not seen there before. Clearly it was attached to the bottom and had long, wavy green stalks and leaves that rippled in the current. It’s really kind of pretty. I was wondering, what is this plant?

Southern Naiad in flowing water

Various Phinizy Center staff helped me figure it out.  I showed photos on my camera to Aaliyah Ross and Jen McGruter in Education, and they began flipping through books in their library.  Jen grabbed a D-net, and we went back to the boardwalk, where she used the net to fish out some of the plant.

Southern Naiad close-up

You can see it has long, slender stems and very skinny leaves.  The leaves on the tips of the stalks round out into spatulate forms.  Jen really had to tug to get some of the plant to break away from the bottom, so it is pretty strongly rooted.

Southern Naiad branching habit

Jen examined the branching structure of the leaves.  Here, the leaves appear to branch off in pairs along a given stem.

Then we trekked over to the Research building, and asked Nate Hobbs what he thought.  He directed us back to a very small book in the Education office, where we found an entry on Southern Naiad, or Najas guadalupensis, which is a native species to our area.  Ruth Mead came in just then and confirmed we had found the right plant.

I felt like I had taken up too much of everyone’s time, but Jen assured me that this had been useful – now they had an identification on another native plant found right in Phinizy Swamp.

Here’s what I learned about Southern Naiad.  It’s found over most of North and South America, in fresh waterways such as lakes, ponds, streams, and canals.  The plant can grow up to about 10 feet long – it may need to if the waterway is that deep, since it’s rooted to the bottom and the leaves need to reach the sunlight near the surface for photosynthesis.  There are about 40 naiad species worldwide.  The leaves are quite narrow and grow in opposite pairs or in whorls of three.  The leaves have little teeth shapes on the margins, but you will need magnification to see the teeth on some varieties of the plant.  You’ll also need magnification to see the flowers – they are tiny.

Southern Naiad is an annual.  It spreads easily by seed or by bits of the plant breaking off and rooting elsewhere.  In some situations, it is considered a weed because it grows so fast and can take over the space in a pond or stream.  However, you can’t argue that it’s taken over at the Phinizy Swamp boardwalk – it’s clearly not overabundant relative to everything else growing nearby.  Southern Naiad is a primary food for turtles and waterfowl.  Macroinvertebrates (tiny water animals that are just large enough to see with the naked eye) find shelter in this plant.

Finally, the way the long green strands ripple in the water kind of reminded me of mermaid hair.  That’s a good association with the plant’s name.  Naiads were female water spirits in ancient Greek mythology.

Things to see at the swamp right now: more signs of spring

by Priscilla Hollingsworth

It seems like the more I look at the swamp, the more there is to see. These are things I noticed during the past week.

swamp trees

A week or two ago, everything seemed to be that gray-brown color of winter in the swamp.  But here you see some grasses growing.  And there is a little flash of red in the trees in the background – this is because the Red Maple tree has lots of red seeds to show.


red maple seeds

Another view of the Red Maple seeds that are so dramatic right now.  Red Maple is also called Swamp Maple – how appropriate – and its Latin name is Acer rubrum.  Some people call the seeds “helicopters” because of the way they twirl in the air when they fall to the ground.  Interestingly, Red Maple is both flood- and drought-tolerant.


red maple seeds in closeup

And here’s a closeup showing the shapes of the seeds with their winglike structures.


greening under trees

Here’s an area under trees that has greened up quickly.  The little green plants are almost all non-grass types that grow very quickly.


sea myrtle greening

The Sea Myrtle is showing small green leaves.  Sea Myrtle, or Baccharis halimifolia, has spread inland in our area – it originally was native to the coast.  It is a wetland plant.


cypress trees getting leaves

The Bald Cypress trees are getting their leaves again – you can see the rusty-colored leaf growth coming in at the tops of the trees right now.  Bald Cypress, or Taxodium distichum, is called “bald” because it loses its leaves in the winter.


6cypress leaves 2

Another view of a cypress tree getting its leaves out.


spanish moss in the rain

Spanish Moss (Tillandsia usneoides) with raindrops clinging to it.  Okay, not so much a sign of spring!  But I couldn’t resist the photo, and walking in the rain when it’s not that cold any longer can be fun.


wolf spider

This was a rather large spider that I encountered on the walk outside the Visitors Center.  What do you think about spiders?  This one was about an inch long, and I observed it carefully while not getting too close.  Looking it up, it seems most likely to be a Wolf Spider, possibly a Hogna helluo or Hogna carolinensis.  Wolf spiders are a large category, so perhaps it is better just to say this one is probably in family Lycosidae.  Wolf spiders often love wetlands and wet forest areas.  Most wolf spiders are active at night, so I don’t know why this one was out in the daytime.  They can bite people, but are not likely to unless people poke at them over and over again (moral: leave the spider alone, and it will leave you alone).


Carolina jasmine buds

You’ve probably seen this plant – it’s Carolina Jasmine, or Gelsemium sempervirens.  Carolina Jasmine is a native plant, and many people encourage it in their yards when it appears spontaneously.  But at the swamp, you get a chance to see it in its natural state.  The photo above shows yellow buds almost ready to open.


Carolina jasmine in bloom

And here, some of the flower buds are open.


wild Bradford pear invasive in bloom

Finally, I promised earlier to post a photo of a Bradford pear tree-turned wild, in bloom.  It’s really pretty, isn’t it?  But sad that these suburban self-hybriding escapees are becoming so invasive in our landscapes locally.


Bradford pear invasive hybrids blooming

Above is a photo of escaping/proliferating Bradford pear descendants along Doug Barnard Parkway, on the way to the swamp.  Take a look as you drive along this and other major roads in Augusta.  In situations where road crews trim back highway growth about once a year, you will see these trees proliferating savagely.  Cutting them back about once a year is the best way to make them spread all the faster.  I don’t know what the solution is – I think that has still to be discovered.

New Park Species! Meet the Brazilian Free-Tailed Bat

New Park Species! Meet the Brazilian Free-Tailed Bat

By: Chalisa Fabillar


One of the perks of my job is that ‘going to the office’ is that my “office” is in such close proximity to an amazing diversity of wildlife. Every season, actually every day, there’s a chance to see and/or hear something new. Last Friday was one of those days when I got to see something new.

If you are familiar with the park species lists, I’m going to suggest you take another look. We just added a new mammal!

Tadarida brasiliensis

IMG_4492Our new species is the Brazilian free-tailed bat, sometimes called the Mexican Free-tail bat. Of the 16 species of bat found in Georgia, only this one has a tail that extends past the tail membrane, hence the name free-tailed. (See the little mouse tail?)

Like most bats, these bats are mostly nocturnal insectivores that use echolocation to navigate the night sky and locate food.

These bats will gather in roosts that can be found in caves, under bridges, in tree holes, and sometimes under loosened bark on trees. Their range extends from as far south as South America all the way to North America. In the U.S., they can be found from as far west as Oregon all the way east to North Carolina.

Their predators include red-tailed hawks, American kestrels, owls that will catch them in flight, opossums, raccoons, skunks and several species of snakes that will prey on them in their roosts.

Daytime Sightings

photo 6Our sighting occurred during the day, which is a bit odd. If you should happen to see a bat out during the day, you might contact your local animal control agency or GA DNR. You might take some photos from a safe distance and show them off to your friends. But the best thing you can do, for your sake and theirs, is to leave these animals alone. In the words of another, “love ‘em and leave ‘em wild!”

A few other interesting tidbits:

  • In some caves, like Carlsbad Caverns, the colonies are so large when they leave en masse at dusk they can be seen on radar as rising “angels.”
  • Females can gather in maternity colonies, where they give birth and raise their single pup. These colonies can be as large as millions of members. Think Carlsbad Caverns!
  • Because their numbers are so high, they are thought to be the most abundant mammal in North America.
  • Bat guano has high concentrations of phosphorous and nitrogen. Because of this, it has been collected for fertilizer and to make gunpowder.
  • During the Civil War, bat guano caves were used extensively in the South as a source of raw materials for gunpowder manufacture.
  • Scientists have found that bats are known to sing! Besides humans, only whales and birds have been detected to engage in this complex activity.
  • They can eat up to half their body weight in insects every night. That could be more than a thousand mosquitoes every night.
  • Females become sexually mature around nine months, males on the other hand take nearly twice that long. Sound familiar?
  • Though brazilian free tailed bats had been residents of the University of Florida football stadium for some time, it was the smell of their poo that eventually led to their removal. Actually, it wasn’t until the governor complained about the odor that university officials came up with a plan to have them safely removed. The university brought in an architect and had a bat house built. It took a few years, but now tens of thousands of bats use specially built bat houses each night. The impressive sight of their dusk and dawn comings and goings regularly draws crowds and has even made to the University’s list of Top 10 sights to see! See streaming video of their colony here.

Chorus Frogs

Chorus Frogs
By: Matt Erickson

Chorus Frogs

Frog choruses can usually be heard on warm, wet nights, but February is right in the middle of calling season for the southern chorus frog. Calling in the winter and spring with cold weather has some advantages. It allows them to breed in temporary Chorus Frogs 2wetlands that might not hold water in the summer months and helps them avoid predators like snakes that are only active during warmer periods. Their call is a high-pitched, slow trill that sounds like a ratchet or something dragging the teeth of a comb. These frogs are common and abundant, so there is a good chance you’ll hear them if you listen for them. They spend time in wet, grassy areas and can often be found around retention ponds and roadside ditches.