Monday, October 17, 2016

GP Longleaf Pine Burn

Hurricane Matthew brought wind and rain to the southeast. Four Holes Swamp filled short of last October's record water levels, but rose over the deck of the boardwalk and overflowed swamp-crossing roads like US Hwy 78. However, the weather after the storm has been cooler, less humid, without precipitation and with winds generally out of the northeast.
Map of tract, Image Mark Musselman
To conduct a prescribed fire at the GP longleaf pine tract, the first tract planted at the Francis Beidler Forest, wind direction is important. Due to the tract's location on the west side of Hwy 27, the winds must be from the northeast or east to prevent smoke from crossing the highway and presenting a danger to drivers. However, northeast winds are not the common wind direction for our area and are often preceded by or accompanied by precipitation.  Spoiler alert: precipitation tends to put a damper on fires and fuels.

Therefore, after clearing the nature center's driveway of fallen trees and the fire break around the GP tract of several stout fallen oaks, we sent out a call for volunteers to help with the prescribed fire on Friday.
Volunteers! (l to r) Bob, Bob, Michael, and Joe; Image Mark Musselman
With the fire break disced, the middle fire break was cleared with a leaf blower in order to burn the 21-acre tract in two units. A test fire was started along the east side of the middle fire break in unit A in order to determine how the fuels would burn. Normally, a test fire is started in a corner in order to allow a rapid extinguishing of the fire should it behave contrary to expectations. However, water oaks have been allowed to infest this tract and are especially dense around the edges. The flat oak leaves do not burn well unless licked by a hot fire pushed by the wind, which allows the fuels to be preheated and dried. Additionally, the majority of fuels on the tract were pine straw and small woody materials, so a test fire in the oak leaves would not reflect conditions across most of the tract.

Test fire, Image Mark Musselman
Note the circular shape of the test fire as it slowly burns evenly in all directions in the absence of wind.

Being satisfied with the fire behavior at the test fire site, we used drip torches to light a line of along the line 2-6. We chose to burn unit A first as it is the closest to the highway and completing it before conditions changed was preferable. Additionally, unit A had been burned two years ago, while unit B had not been burned for 6.5 years, which meant that there would be more fuel on the ground in unit B and the possibility of a larger fire. With a swamp full of water to the west and a burned out unit A to the east, a larger fire in unit B would be easier to contain. As the fire slowly backed into the wind from the eastnortheast within unit A, we began lighting spot strip fires at 20-meter intervals toward the highway. Below is an example from later in the day when we burned unit B.

Spot strip fire in unit B, Image Mark Musselman
Dropping a continuous line of fire uses more diesel/gas fuel and creates a curtain of fire that generates more heat than is desired. By dropping spots of fuel from the drip torches every 10-15 meters, the spots burn out in all directions, like the test fire image, at a lower intensity. Eventually, the spots burn together and the fire briefly intensifies before consuming all the fuel and extinguishing itself.
Spot strip fires burning (left), burned unit A (right), Image Mark Musselman
The result of the fire is a reduction of fuel on the ground, which will limit damage from a wildfire caused by lightning or human negligence. The next rain will help wash the nitrogen from the burnt fuels back into the soil. The bare mineral soil will provide the necessary conditions for longleaf pine seeds to germinate and survive. The seeds can germinate in the duff that existed prior to the fire, but survival is less likely as the duff layer can dry more quickly than the soil allowing the seedling to desiccate. Competing loblolly pines and hardwoods are killed outright or top-killed as they are not adapted to fire like longleaf pines. Grasses and other forbs are invigorated by fire and immediately begin sending out softer material more palatable to deer and other wildlife. Not all desirable plants and animals survive, but on balance, fire is overwhelmingly beneficial to the longleaf pine ecosystem.

At the end of the day, approximately 75% of the 21 acres burned and no smoke reached the highway. Success!
Burned unit A, Image Mark Musselman
Burned area between units (see volunteer image above), Image Mark Musselman
Smoke free!, Image Mark Musselman

Thursday, October 06, 2016

Geolocators 2.0 - Time to Meet the Birds!

In our last post, we described the process for attaching geolocators to a bird as part of our ongoing project with Prothonotary Warblers (read it here). In this second installment, we'll introduce you to the eight birds that we chose to fit with geolocators at Beidler this spring. We gave each bird a nickname based on the colors of their bands in hopes that it will be easier to remember (and find) them next year. Because each bird is assigned an alphanumeric combination based on their band colors, we thought nicknames might be easier to remember instead of codes like A1501 or A1674! As a reminder, both the bands and the geolocator are attached in as quick and safe of way as possible, causing minimal stress to the birds.  
Here's a reminder of the band colors that we've used over the last three years. Note: the three far right bands with split colors are referred to as "year" bands; each was used on every bird banded in a given year, but not used in any other year.

In order to learn anything from these devices, we have to relocate each bird in 2017 and take the geolocator off. With that in mind, we hope that you'll read on, get to know these birds, and come join us in 2017 as we look for these birds on their return trip to the swamp.

Without further ado, it's time to meet the birds!

Aster was one of the first birds banded when Project PROTHO started back up in 2014. He has returned to Beidler Forest at least three times, and he is the first bird that we’ve ever confirmed nesting in the same exact cavity two years in a row! His territory for the last three years has been right near the #7 rest shelter.  His nickname comes from the green and yellow bands on his right leg, colors shared by sunflowers and other members of the Aster family.

Aster - pictured when he was first banded on April 4th, 2014.

One of only two females to receive a geolocator, Blueberry nested in a nest box near where the boardwalk splits to go to the lake. She got her nickname from the blue and black bands on her right leg. Her mate was Lichen, another bird that received a geolocator (meet him below).

Blueberry - named for her blue and black color bands.
Blueberry with geolocator.

The first bird we banded in 2015, Buckeye has spent the last two springs breeding near the rain shelter at #9 along the boardwalk. He's named for the double red bands on his right leg, the same color as the flowers of the Red Buckeye which blooms in the swamp in early spring. He was the last individual to receive a geolocator, which we attached on July 4th weekend. 

Buckeye with his geolocator.

Buckeye's double red bands on his right leg (Photo by Mac Stone).

Like Buckeye, Holly was banded in 2015; in fact, for the last two years these two males have battled over territory near #9. Holly also has a red band on his right leg, but it is accompanied by a green band, just like the red and green coloration of Holly trees that grow in the swamp's drier areas. 

Holly, aka A1501, being released (photo by Mac Stone).

Indigo was first banded on June 11th of this year, and then captured again in early July to carry a geolocator. He nested with a female on top of the nest box that's attached to the back of the sign next to the observation tower at the lake. He sports a blue and green band on his right leg, hence his nickname reminiscent of the flowers of Wild Indigo growing in the fields adjacent to the swamp.

Meet Indigo! (Sorry, don't have a photo of this bands.)

Iris is the second female we tagged this spring. Named for her pretty blue and orange bands like the flowers of the Dwarf Crested Iris, she nested in the cypress knee at the Meeting Tree made famous by Don Wuori's award-winning photograph (scroll down the list of Audubon's 2015 photography award winners at this link). Though not banded until late in the season, we think that she may have attempted to nest three times (or maybe even four!) in the area around the Meeting Tree, something we've never documented in the swamp! Hopefully she'll be back to do it again in 2017.

Look for her near the boardwalk fork and Meeting Tree.
Iris's orange and blue bands.

 Like Aster, Lichen was one of the first birds banded back in 2014. He has come back to Beidler the last two years and always seems to hang out in the area where the boardwalk turns left to go to the lake. This year, he nested with Blueberry in a nest box in that area. He sports a green and gray band on his right leg - which reminded us of the beautiful, subtle colors of the lichens growing on the trees in the swamp. 
Look for Lichen (and his gray and green bands) at the turn to the lake.

Last but not least, our final Prothonotary Warbler with a geolocator is nicknamed "Trillium;" we think the white and yellow bands on his right leg resemble the flowers of the endangered Dwarf Trillium that grows in the dryer areas of the swamp. Trillium nested with a female in a cypress knee at #8 (this is at the snake interpretive sign for those that know their way around the boardwalk). 

Trillium's yellow and white bands.

In just a few short months, we hope all eight of these beautiful birds will be back nesting in the swamp. Once we get into 2017, we'll have another post with a call for volunteers, and some tips for finding Prothonotary Warblers when you visit Beidler Forest.

Thursday, August 25, 2016

Top 5 Tips for Beginner Birders at the Beach

South Carolina beaches are not just home to amazing views and fun in the sun; the coastline also provides vital habitat for both feeding and nesting. Here are a few tips for the aspiring birders out there to catch these coastal birds in action!

1.      Get in Gear
Be sure to pack a hat, sunscreen, bug spray, and plenty of water. If you’re not local then you are sure to find out soon enough that our temps reach over 100 degrees some days. Coupled with our infamous humidity, it is essential to prepare for the heat and the mosquitoes you will encounter in the swampy areas. We recommend bringing about two times the water you think you should.

2.      Choose your spot

Along with our very own Audubon Center & Sanctuary at Francis Beidler Forest, there are tons of coastal birding hotspots in the state. From black water rivers to barrier islands, this list of designated Important Bird Areas is a great place to start your search for a birding adventure.

3.      Identify
Once you start seeing all of our beautiful coastal birds, you are going to want to identify them. We recommend picking up a field guide or use a mobile app for easy access to information on every species of bird in the United States. Merlin and Audubon Bird Guide are both easy and free. There are also all sorts of methods to record each new bird discovery!

4.      Practice makes perfect
Sometimes you’ll get only a quick glimpse of a bird as it perches or flies from one location to another. Practice your identification method by noticing the size and shape, color, behavior, and habitat. The quicker you get, the longer your list will be!

5.      Share the beach

Wherever you roam, be sure to not disturb the birds or their habitat. If you are close enough to agitate the birds into flying away or altering their behavior in any way, then you are too close. Also, make sure to never feed the birds and refrain from bringing pets. Even on a leash, dogs are perceived as predators to birds and will frighten them away.

Photos by Vanessa Kauffmann

Tuesday, August 16, 2016

Geolocators 2.0 - Looking to Further Our Understanding of Prothontoary Warbler Migration

In April 2015, we recovered a single geolocator from a Prothonotary Warbler (aptly named “Longshot”). This small device gave us amazing insight into the migration of the "swamp canary" (read about it here). 

Longshot, pictured here during his recapture in April 2015, wearing the geolocator that he had carried since the previous July.

But in order to learn even more about the migration of this imperiled bird, we deployed eight more geolocators on Prothonotary Warblers earlier this spring. Below, we'll describe the process for attaching these miniature tracking devices to these birds. On our next post, you’ll get to meet the eight special birds that we need your help finding next spring.

We received our shipment of 8 geolocators in May 2016. Each of these tiny devices weighs 0.45 grams, which is about 4% of the body weight of the average Prothonotary Warbler. The general rule for attaching a tracking device to a bird is to stay below 5% of their body weight (in order to not risk negatively affecting it).  Tracking technology miniaturized enough to attach to a bird this small has only been around for the last few years!
Eight light-level geolocators arrive at Beidler Forest in May 2016. Learn how these devices work here.

In order to attach a geolocator to a bird, harnesses are made using Stretch Magic (a common type of jewelry cord). Harnesses are tied in a knot creating two loops, and then precisely measured in order to fit around the legs of a Prothonotary Warbler. Once each harness is accurately measured, they are superglued to the geolocator. 

After the knot is tied, each loop must be accurately measured to a specific length. If the length of the loop is just one centimeter off, the harness might not fit the bird correctly.

Once the harness has been measured, the knot is superglued to the geolocator. Pictured here is Aaron Given, Assistant Wildlife Biologist for the Town of Kiawah Island. Aaron helped us get permitted for this project, make harnesses, and deploy each unit. We couldn't have done this project without his help - thanks Aaron!

Once the glue dries, we trim off the excess cord and the geolocator is officially ready to go!

Once the harnesses are made, we hook the geolocators up to computer software, double-check that they are recording light levels, and then the geolocator is ready to go!

A geolocator with harness attached to leads, allowing us to communicate with the individual unit. We use this to calibrate each geolocator, double-check that they are functioning correctly, and most the data when we (hopefully) recover them next year!

Now that are units are ready to be put out, we strategically choose the best candidate Prothonotary Warblers out of those that we've color-banded in the past. This is one of the most important reasons we color-band: since we can use the bands to identify each bird uniquely, we can monitor their return rates and breeding success. From this data, we can determine which of our birds have 1) migrated in past years and returned to Beidler and 2) successfully bred this year. These two factors often influence an individual's likeliness to return in subsequent years, and thus are good metrics for determining which birds to use in this project. 

With that in mind, the photo below is a quick overview of the band colors that we've used over the last three years. That way you can learn the colors of each bird carrying a geolocator and you'll be ready to help us find them next spring!
Each bird gets an aluminum band (marked as "A" on right) with a number on it, as well as a unique combination of three colors. Since the bands weigh next to nothing, there is no worry of them hurting or adversely affecting the birds. Using the numbers below each color, we assign an alphanumeric code to each bird.

Contrary to what you  might think, the harness and geolocator do not go over the birds' wings (although sometimes we call it a backpack); instead, they go over the legs and each loop rests up near the bird's hip. 

Putting on the first geolocator.

First gelocator attached! The unit is designed so that the light stock (the lower, white end) points up from the bird, thus allowing it to record light level readings without accidentally being hidden beneath feathers or obstructing the bird's flight.

In our next blog post, we'll introduce to you the eight Prothonotary Warblers that received geolocators in 2016 so that you can join us in looking for them next year when they hopefully return to Beidler Forest!


Wednesday, August 10, 2016

Project PROTHO Intern

Thanks to Mr. and Mrs. Anderson for their generous donation to Audubon South Carolina in memory Lloyd and Margaret Cone, we were able to fund a seasonal internship aimed at increasing our monitor efforts of the Prothonotary Warbler at three locations across Four Holes Swamp – two areas in old growth and one area that was logged onceHeather VanTassel, our intern, received her bachelor’s degree in Biology from Carlow University. She went on to obtain her PhD in Ecology from the University of California Riverside focusing on understanding wildlife responses to anthropogenic disturbances in the southwest.
Old-growth Swamp - Heather VanTassel
With Heather's assistance, we have learned that while Prothonotary Warbler densities may not seem to be as high in the logged areas as they are in the old-growth swamp, the once-logged areas still maintain healthy densities of Prothonotary Warblers. These results reinforce our efforts to conserve Four Holes Swamp and allow once-disturbed sites to return to their natural state in order to support healthy bird communities. We also plan to put out 50 Prothonotary Warbler nest boxes in the logged locations, which will provide additional nesting cavities and help maintain Prothonotary Warbler densities in the future.

Project PROTHO Nest Box - Heather VanTassel
You can follow what we are doing with Project PROTHO on our webpage.

Prothonotary Warbler Nestlings - Heather VanTassel

Saturday, July 23, 2016

To Rattle Or Not To Rattle

Snakes rattle their tails as a warning, but not all snakes exhibiting this behavior are rattlesnakes.

Here an Eastern Cottonmouth rattles its tail to warn of its presence and desire to be left alone.

Rattlesnakes have evolved an amplification method for their tail twitching. Some dry skin remains at the end of their tail each time they shed skin, which allows for a rattle louder than a tail simply moving in dry leaves. Tail twitching is a method of announcing a snake's presence and the rattle is a highly effective design. However, rattling the tail is generally an action of last resort, so many snakes will not rattle even if a human is close.

There are stories suggesting that rattlesnakes are evolving back to quieter snakes without rattles, because non-rattling snakes go undetected and survive. However, there are not any studies that show snakes are rattling less frequently than in the past. Snakes obviously do not want to reveal their location to prey they are trying to eat and unnecessarily revealing their location to non-prey animals may result in death or injury (see the Internet for numerous images of snakes shot or chopped before they could do any "harm"). Remaining motionless and allowing camouflage to work likely allows  snakes to go unnoticed and unharmed. Conversely, if a snake feels that death or injury is imminent, rattling the tail may cause the source of potential danger to move away. It always works with me.

Besides the encounter shown in the video above, other Eastern Cottonmouth snakes have alerted me to their presence when they felt I was too close. While patrolling in the swamp, I saw snake tracks in the mud, but could not find the snake. I did not want to step any farther without knowing exactly what was sharing my close surroundings. The polite cottonmouth, a few feet to my right, rattled its tail against the dead log atop which it rested to let me know its location and that it preferred to be left alone. I obliged and safely moved away. It was possessive of space, but not aggressive.

Eastern Cottonmouth - Mark Musselman
After the great rain of October 2015, I was patrolling the edge of the swamp near the nature center for signs of wild pigs. I hoped that the high water would have them bunched at the edge of the swamp and vulnerable to elimination. I looked up long enough to identify a vehicle moving down the driveway, which was exactly the amount of time needed to step squarely on the back of a Timber Rattlesnake. Sensing the textural difference from my previous thousands of steps, I lifted my foot. The snake moved off a safe distance, coiled and then rattled its disapproval. I took an image, thanked it for its subdued reaction to my "attack" and moved safely away.

Timber Rattlesnake - Mark Musselman
Though the event listed below has become history, we do offer speaker presentations, including one on our friends the snakes. We can all benefit from a better understanding of these reptiles.

Monday, July 18, 2016

Warm Season Burn - Update

One month ago (see previous post), we attempted a warm season burn on 29 acres of old agricultural fields in which our planted longleaf pines were being crowded by other vegetation, mainly dog fennel. Last Thursday, we checked on the progress of the longleaf pines and grasses in the field where the burn was successful.
Grasses under dead dog fennel - Mark Musselman
In areas where the burning was complete, the dog fennel remains dead or absent and the grasses have pushed out new green blades.

With most of the vegetation burned away and the longleaf pine pushing out new needles of a brighter green than the grasses, the longleaf pines are more easily located than before the burn.

Longleaf pine growth after fire - Mark Musselman
Longleaf pine growth after fire - Mark Musselman
Longleaf pine growth after fire - Mark Musselman
Longleaf pine growth after fire - Mark Musselman
With the majority of the competition removed, especially the tall dog fennel, the young longleaf pine are in full sunlight and should grow rapidly over the coming months. By spring, many will have a root collar of one inch and will begin vertical growth leaving the grass stage behind. We look forward to the day when the longleaf pine stand taller than the neighboring grasses!