Although we have walked more than a thousand times the 1.75 miles of boardwalk at the Audubon Center at Francis Beidler Forest, each trip provides us with a first of some sort. On Tuesday, it was too easy as Bells Elementary School from Ruffin, SC had never made a visit to the Francis Beidler Forest. Being in a swamp was a first for most of the fifty students and visiting the old-growth of Beidler Forest was a first for all of the students.
With the recent heavy rain, the swamp along the boardwalk went from mostly dry with water in a few shallow creek channels on Friday to shallow water along the entirety of the boardwalk on Tuesday. We observed numerous Eastern Mud Turtles (Kinosternon subrubrum subrubrum) swimming below the water's surface as they investigated newly-submerged areas for food. Juvenile White Ibis (Eudocimus albus) were scattered along the walk in groups of 3-4 birds probing the shallow water with their curved bills. Several species of woodpeckers seemed to be announcing the progress of our walk to the other swamp residents. Normally, the job of annoucing our presence in the swamp is left to the Barred Owls (Strix varia). Though the owls were not vocal as we walked back toward the center for lunch, they did make a silent, low pass ahead of the group and perched nearby in the open for all to absorb a lengthy, first-time look at the species.
At one point during the tour, a sharp-eyed fifth grader spotted a small, smooth, reddish caterpillar on the boardwalk handrail. We had never seen the species of caterpillar and did not have a field guide to identify this first for us. Unfortunately, we did not have a camera available, so we did not capture an image to use for identification later in the office. The next time we come across the species will be our first time to identify it for our insect list.
Finally, we spotted a Yellow-billed Cuckoo (Coccyzus americanus) that had captured a giant, green caterpillar and was attempting to subdue its prey for easy consumption. We have seen cuckoos before, but never one with prey. We could not positively identify the caterpillar, but its size (approximately 12 cm or 5" long!) eliminates the vast majority of caterpillar species. A prime candidate is the Royal Walnut Moth's (Citheronia regalis) caterpillar (a.ka. Hickory Horned Devil). Field guides use words like "behemoth" to describe this fearsome-looking though harmless caterpillar. Possibly out of fear of dropping its prized meal (easily 12 times the RDA for caterpillar protein), the cuckoo continued to move lower in the canopy with the squirming caterpillar in its sturdy bill. Once on the ground, the bird repeatedly and vigorously beat the caterpillar on the ground. The cuckoo flew off before we could see the act of caterpillar consumption, but tenderized or not, the pickle-sized caterpillar was going to be a challenge to swallow!
No camera was available for images.
Thursday, September 30, 2010
Wednesday, September 29, 2010
TogetherGreen Volunteer Cleanup Results
On Saturday, ten volunteers joined two of the Audubon Center at Francis Beidler Forest staff as part of the TogetherGreen Volunteer cleanup of the swamp along U. S. Highway 78. Unfortunately, another twenty volunteers were expected, so the entire targeted area was not cleaned. However, those volunteers that showed did a tremendous job during the three hours of work!
Dressed in orange vests and armed with litter grabbers provided by Keep Dorchester County Beautiful, volunteers hit the treeline south of U. S. Highway 78. The majority of the litter was located from the edge of the road, down the steep embankment, and approximately six feet into the treeline. Previous high water in the area concentrated much of the litter at the base of the road embankment. The main reason for targeting this area of the swamp was to eliminate the litter, nearly all of which was floatable, before the next round of high water washed it downstream. The rain of the last few days has caused the water at Bridge Lake (where US Hwy 78 crosses the water at the east end of the yellow-shaded area) to rise five feet. Sadly, the red-shaded area shows where we were able to clean and we did not reach Bridge Lake. Some of the litter we did not collect may well be on its way downstream to the Edisto River.
During our daily commute to the Audubon Center at Francis Beidler Forest, we have observed lightweight trash escaping from garbage trucks rumbling along U. S. Highway 78. However, easily 95% of the trash we collected consisted of beverage containers (glass beer, liquor and soda bottles; plastic soda and water bottles; aluminum beer and soda cans; foam coffee cups; and paper soda cups) that were likely thrown from a passing vehicle. It is possible that some of the lightweight beverage containers blew out of garbage trucks, but the glass containers or the plastic bottles partially-filled and capped were certainly launched into the swamp by motorists. Unless attitudes change, the 0.4 miles that we cleaned will inevitably fill with litter to match the remainder of the highway right-of-way.
Remember in school when you asked, "When am I ever going to use this math?" Well, sharpen your pencil because it's time! Twelve individuals working for three hours along 0.4 miles on one side of a road will pick up how many bags of trash? One, two, three...carry the nine...and the answer is 103 bags or one full dump truck! Remember, that's 0.4 miles on ONE side of the highway...that's lousy math.
Images by Mark Musselman
Dressed in orange vests and armed with litter grabbers provided by Keep Dorchester County Beautiful, volunteers hit the treeline south of U. S. Highway 78. The majority of the litter was located from the edge of the road, down the steep embankment, and approximately six feet into the treeline. Previous high water in the area concentrated much of the litter at the base of the road embankment. The main reason for targeting this area of the swamp was to eliminate the litter, nearly all of which was floatable, before the next round of high water washed it downstream. The rain of the last few days has caused the water at Bridge Lake (where US Hwy 78 crosses the water at the east end of the yellow-shaded area) to rise five feet. Sadly, the red-shaded area shows where we were able to clean and we did not reach Bridge Lake. Some of the litter we did not collect may well be on its way downstream to the Edisto River.
During our daily commute to the Audubon Center at Francis Beidler Forest, we have observed lightweight trash escaping from garbage trucks rumbling along U. S. Highway 78. However, easily 95% of the trash we collected consisted of beverage containers (glass beer, liquor and soda bottles; plastic soda and water bottles; aluminum beer and soda cans; foam coffee cups; and paper soda cups) that were likely thrown from a passing vehicle. It is possible that some of the lightweight beverage containers blew out of garbage trucks, but the glass containers or the plastic bottles partially-filled and capped were certainly launched into the swamp by motorists. Unless attitudes change, the 0.4 miles that we cleaned will inevitably fill with litter to match the remainder of the highway right-of-way.
Remember in school when you asked, "When am I ever going to use this math?" Well, sharpen your pencil because it's time! Twelve individuals working for three hours along 0.4 miles on one side of a road will pick up how many bags of trash? One, two, three...carry the nine...and the answer is 103 bags or one full dump truck! Remember, that's 0.4 miles on ONE side of the highway...that's lousy math.
Images by Mark Musselman
Friday, September 24, 2010
TogetherGreen Volunteer Day
The Francis Beidler Forest once again has been awarded a TogetherGreen Volunteer Days grant to aid in the effort to increase volunteer participation at the sanctuary while simultaneously achieving their conservation goals. Sponsored by Toyota Motor Sales USA, TOGETHERGREEN VOLUNTEER DAYS are events designed to connect people with enjoyable opportunities to make a difference for conservation in their neighborhood. Beidler Forest Center Director, Mike Dawson says, “Volunteerism is the key to shaping a healthy environmental future. It gives people a chance to make positive changes; to learn more about the pressing issues affecting local wildlife and habitat; and to meet others with shared interests.”
Tomorrow from 9:00 AM til noon, Audubon staff and volunteers will be traipsing through the swamp woods that parallel State Road 78 where it crosses Four Holes Swamp (shaded yellow area) in search of all manner of litter and trash in an attempt to clean up this important stretch of the swamp. This is the route that garbage trucks take on their way to the local landfills and unfortunately an embarrassing amount of trash and litter blows out of these trucks along the way and ends up in the swamp bottom. They plan to attack the road and woods edge armed with trash bags and as many volunteers as can be mustered and hopefully clean up the entire road frontage. The project is not just about beautifying the main approach route to the Beidler Forest, but will also be good for water quality, as when the water level rises in the swamp, much of the debris is carried off downstream. Volunteers should dress for the weather, long pants are recommended and bring some work gloves (and a “picker upper” if you have one!) Drinks, TogetherGreen T-shirts, hats, or totes and free passes to the Beidler Forest will be available to all participants.
Plan on meeting at the small county park located at the intersection of Highway 78 and 178 (see push pin on map). Please call 843-462-2150 for directions or more information. To learn about other volunteer opportunities at Beidler Forest, go to http://www.beidlerforest.com/ and hit the Volunteer tab!
Images by Mark Musselman
Tomorrow from 9:00 AM til noon, Audubon staff and volunteers will be traipsing through the swamp woods that parallel State Road 78 where it crosses Four Holes Swamp (shaded yellow area) in search of all manner of litter and trash in an attempt to clean up this important stretch of the swamp. This is the route that garbage trucks take on their way to the local landfills and unfortunately an embarrassing amount of trash and litter blows out of these trucks along the way and ends up in the swamp bottom. They plan to attack the road and woods edge armed with trash bags and as many volunteers as can be mustered and hopefully clean up the entire road frontage. The project is not just about beautifying the main approach route to the Beidler Forest, but will also be good for water quality, as when the water level rises in the swamp, much of the debris is carried off downstream. Volunteers should dress for the weather, long pants are recommended and bring some work gloves (and a “picker upper” if you have one!) Drinks, TogetherGreen T-shirts, hats, or totes and free passes to the Beidler Forest will be available to all participants.
Plan on meeting at the small county park located at the intersection of Highway 78 and 178 (see push pin on map). Please call 843-462-2150 for directions or more information. To learn about other volunteer opportunities at Beidler Forest, go to http://www.beidlerforest.com/ and hit the Volunteer tab!
Images by Mark Musselman
Friday, September 17, 2010
iPod Touch Grant Presentation
As the education director at the Audubon Center at Francis Beidler Forest and a teacher consultant (TC) for the South Carolina Geographic Alliance (SCGA), Mark Musselman was awarded a $1000 SCGA teacher grant in 2009.
One requirement of the grant is a presentation to teachers at the Fall 2010 Geofest. The iPod Touch allows us to put an incredible amount of data into the hands of students while they are on the boardwalk and in the middle of the old-growth, cypress-tupelo swamp. For example, students can call up the satellite image shown below and see the boardwalk drawn onto the swamp. If we are standing on the backside of the boardwalk south of the fork, we can ask the students, "Why does the image look lighter to the west of the boardwalk than it does to the east of the boardwalk?" From the boardwalk, a quick glance to the west reveals that the elevation of the land is slightly higher causing the area to be dry, which in turn allows different types of vegetation to grow in that area. Looking to the east, students can see land at a slightly lower elevation, which allows water to accumulate thereby allowing wetland-adapted species of plants to dominate. Seems like a simple concept, but it would be difficult for most students to visualize, if they had the same satellite image, but were sitting at their desk in a classroom.
The iPod Touch can also hold gigabytes worth of data in the form of images, video, audio, field guides, research projects, student-generated text or audio, a seemingly-infinite number of apps, and our own boardwalk-specific app. With these tools, especially our boardwalk-specific app, we provide students the ability to answer our questions as well as those that they develop.
Although the Francis Beidler Forest is unique and we find it to be a wonderful place to work, there would be little incentive for students to visit if they already knew all the answers regarding the swamp and the rest of our natural environments. However, without the ability for students to find the answers on their own, the only other form of instructional delivery is for the guide to verbally present all the information. Not all students learn well that way and even those that do will appreciate some instructional variety.
We currently have 10 iPod Touches available for use with visiting school groups and are working towards a set of 25 (2 students per unit). Check our education department calendar to see what dates are available for your students to visit!
Images by Mark Musselman
One requirement of the grant is a presentation to teachers at the Fall 2010 Geofest. The iPod Touch allows us to put an incredible amount of data into the hands of students while they are on the boardwalk and in the middle of the old-growth, cypress-tupelo swamp. For example, students can call up the satellite image shown below and see the boardwalk drawn onto the swamp. If we are standing on the backside of the boardwalk south of the fork, we can ask the students, "Why does the image look lighter to the west of the boardwalk than it does to the east of the boardwalk?" From the boardwalk, a quick glance to the west reveals that the elevation of the land is slightly higher causing the area to be dry, which in turn allows different types of vegetation to grow in that area. Looking to the east, students can see land at a slightly lower elevation, which allows water to accumulate thereby allowing wetland-adapted species of plants to dominate. Seems like a simple concept, but it would be difficult for most students to visualize, if they had the same satellite image, but were sitting at their desk in a classroom.
The iPod Touch can also hold gigabytes worth of data in the form of images, video, audio, field guides, research projects, student-generated text or audio, a seemingly-infinite number of apps, and our own boardwalk-specific app. With these tools, especially our boardwalk-specific app, we provide students the ability to answer our questions as well as those that they develop.
Although the Francis Beidler Forest is unique and we find it to be a wonderful place to work, there would be little incentive for students to visit if they already knew all the answers regarding the swamp and the rest of our natural environments. However, without the ability for students to find the answers on their own, the only other form of instructional delivery is for the guide to verbally present all the information. Not all students learn well that way and even those that do will appreciate some instructional variety.
We currently have 10 iPod Touches available for use with visiting school groups and are working towards a set of 25 (2 students per unit). Check our education department calendar to see what dates are available for your students to visit!
Images by Mark Musselman
Thursday, September 16, 2010
New Bird for Beidler Forest
Since its purchase in 1969, the Francis Beidler Forest has been studied and lists have been compiled cataloging the plants and animals within its boundaries. Some groups of animals have been studied more thoroughly than others. Insects remain a critical component of the swamp ecosystem, but have received little direct attention. We continue to add species to the list as we discover them in the process of completing our regular duties. Birds are another story.
Being that the National Audubon Society formed from grassroots efforts to end the killing of birds for the fashion industry and continues to work for the protection of birds and their habitat, it is no surprise that the bird list for the Francis Beidler Forest is extensive. Additionally, thousands of people a year have been looking at birds after the completion of the boardwalk in 1977. There are very few surprises when in comes to birds at the Francis Beidler Forest. That's part of what makes yesterday's bird sighting interesting.
Previously in this blog (May, June), we have covered beavers (Castor canadensis) and their return to the Francis Beidler Forest. Yesterday, we wanted to take the Global Positioning System (GPS) unit and capture coordinates for the beaver dam (shown in blue) in order to show its location on maps of the boardwalk area. The water level is quite low, so walking along the low dam was not difficult and we were out of the office. A short dam near the nature center keeps water from leaking up a low draw, while the 1/4-mile section of dam ties the lodge under the powerline to the high ground near the fork of the boardwalk. There is another 1/4 mile of dam that runs north from the lodge to the swamp across the powerline right-of-way, but we ran out of time and did not gather its coordinates. Good excuse for another day out in the swamp.
Along the way, we saw or heard a Belted Kingfisher (Ceryle alcyon), Red-shouldered Hawks (Buteo lineatus), a Common Yellowthroat (Geothlypis trichas), a Wood Duck (Aix sponsa), an Anhinga (Anhinga anhinga), and a juvenile White Ibis (Eudocimus albus). All of these birds were taking advantage of the pooled water and altered habitat created by the beavers' dam. We were certain that we had not detected all of the animals benefitting from the beaver activity, but we were surprised when an American Bittern (Botaurus lentiginosus) lifted from the tall grass on one side of a swollen creek channel and quickly dropped into the vegetation cover on the other side of the channel before we could take a picture. Bitterns of any sort have not been seen within the boundaries of the Francis Beidler Forest due mainly to the lack of suitable habitat. However, with the powerline right-of-way being kept clear of trees and the beavers pooling water that normally would have quickly drained to the Edisto River, the habitat in that small portion of the swamp now has the feel of a marsh...and bitterns feel comfortable in its dense cover.
It was another day in the swamp, but as always, it was something new and exciting!
Images by Mark Musselman
Being that the National Audubon Society formed from grassroots efforts to end the killing of birds for the fashion industry and continues to work for the protection of birds and their habitat, it is no surprise that the bird list for the Francis Beidler Forest is extensive. Additionally, thousands of people a year have been looking at birds after the completion of the boardwalk in 1977. There are very few surprises when in comes to birds at the Francis Beidler Forest. That's part of what makes yesterday's bird sighting interesting.
Previously in this blog (May, June), we have covered beavers (Castor canadensis) and their return to the Francis Beidler Forest. Yesterday, we wanted to take the Global Positioning System (GPS) unit and capture coordinates for the beaver dam (shown in blue) in order to show its location on maps of the boardwalk area. The water level is quite low, so walking along the low dam was not difficult and we were out of the office. A short dam near the nature center keeps water from leaking up a low draw, while the 1/4-mile section of dam ties the lodge under the powerline to the high ground near the fork of the boardwalk. There is another 1/4 mile of dam that runs north from the lodge to the swamp across the powerline right-of-way, but we ran out of time and did not gather its coordinates. Good excuse for another day out in the swamp.
It was another day in the swamp, but as always, it was something new and exciting!
Images by Mark Musselman
Monday, September 13, 2010
Heart of the Swamp - Photo Hunt
Tara Bailey, seasonal naturalist at the Audubon Center at Francis Beidler Forest, had the following printed in the Summerville Journal Scene.
Published Thursday, September 09, 2010 1:31 PM
Summerville Journal Scene ®
The photographer was looking for snakes, specifically. He had photographed warblers, damselflies, spiders, and two deer, but the legless reptiles of Biblical notoriety had so far proven evasive.
It was frustrating, because the Audubon Center at Beidler Forest in Harleyville is a home to snakes, mostly water snakes, though it’s always a treat to spot the very top of the food chain - the cottonmouth. The photographer left the boardwalk with his camera card full of wildlife, though void of snakes, but soon another man appeared and reported that he’d had great success in finding both a brown water snake and a cottonmouth.
He told the photographer the specifics of their locations, so the two of us went back onto the boardwalk – he, to photograph; me to guide him to the snakes. We kept our eyes focused on sunny spots within stumps and on logs, in wild, viney growths, and wherever else a snake might enjoy absorbing heat. No luck.
However…
There’s no such thing as an eventless walk through a swamp. It would be like a dry ocean or a quiet Christmas. If you keep your peripheral vision on guard, slate-tinted immature ibises come into focus while stalking minnows in the tannin water. Branches fall to the ground, and somewhere in the tree is the source of the timbering. Bubbles suddenly appear on the water’s surface, and an unidentified sound is coming from, you think, the left.
Who knows what spies you from above the leaves, below the mud, or within the hollows of ancient cypress and tupelo trees…
What life you discover is but a mere sampling of what exists within the Beidler Forest’s 16, 000 acres, 1,763 of which is virgin growth – one of two primary growth forests that remain in the state. And what you can’t see, you almost certainly can hear. The photographer was also on the lookout for pileated woodpeckers, which were teasing him with their calls, yet remaining concealed within the forest. The moment the photographer drove away, the large, red-crested bird flew overhead and crossed to another stand of 1,000-year-old trees. Not the photographer’s lucky day.
At least, not for finding snakes and woodpeckers. But the photographer didn’t leave disappointed. He’d driven hours to get here and promised to return, calling it one of his “hotspots.” For no matter what one encounters out here, there is always life in the heart of the swamp.
Image by Mark Musselman
Published Thursday, September 09, 2010 1:31 PM
Summerville Journal Scene ®
The photographer was looking for snakes, specifically. He had photographed warblers, damselflies, spiders, and two deer, but the legless reptiles of Biblical notoriety had so far proven evasive.
It was frustrating, because the Audubon Center at Beidler Forest in Harleyville is a home to snakes, mostly water snakes, though it’s always a treat to spot the very top of the food chain - the cottonmouth. The photographer left the boardwalk with his camera card full of wildlife, though void of snakes, but soon another man appeared and reported that he’d had great success in finding both a brown water snake and a cottonmouth.
He told the photographer the specifics of their locations, so the two of us went back onto the boardwalk – he, to photograph; me to guide him to the snakes. We kept our eyes focused on sunny spots within stumps and on logs, in wild, viney growths, and wherever else a snake might enjoy absorbing heat. No luck.
However…
There’s no such thing as an eventless walk through a swamp. It would be like a dry ocean or a quiet Christmas. If you keep your peripheral vision on guard, slate-tinted immature ibises come into focus while stalking minnows in the tannin water. Branches fall to the ground, and somewhere in the tree is the source of the timbering. Bubbles suddenly appear on the water’s surface, and an unidentified sound is coming from, you think, the left.
Who knows what spies you from above the leaves, below the mud, or within the hollows of ancient cypress and tupelo trees…
At least, not for finding snakes and woodpeckers. But the photographer didn’t leave disappointed. He’d driven hours to get here and promised to return, calling it one of his “hotspots.” For no matter what one encounters out here, there is always life in the heart of the swamp.
Image by Mark Musselman
Sunday, September 12, 2010
Geographic Information System - Seeing Patterns
Audubon South Carolina uses geographic information system (GIS) software for a variety of purposes. As we've previously noted: GIS software allows one to take a mountain of data and view it graphically in any desired combination. In this way, patterns and relationships can be more easily detected.
The first image shows a bird's-eye view of the boardwalk here at the Francis Beidler Forest. The nature center and the beginning of the boardwalk are at the upper left. Goodsen Lake is shown at the lower right. North is at the top of the image. The data layers shown include the boardwalk; the species (flora and fauna) sighted over the last few years; the buildings and shelters; the low boardwalk trail; and the property boundaries. Other layers on file include the canoe trail; Project PROTHO data such as nest locations, banding locations, banded bird sightings, and territories; access gates; habitat restoration sites; breeding bird survey plots; etc. What makes GIS technology a powerful tool is the user's ability to view the data separately or in combination with other, sometimes seemingly unrelated, data.
The species data are shown as individual points in the image with each type (plant, mammal, bird, reptile, insect, fish, etc.) shown in a unique color. Though the separate dots are difficult to see in the image, the software allows the user to zoom in. It should be clear that the green dots are the most seen animals. Based on our organization's focus, one could guess correctly that the green dots represent birds.
Using the data shown in the image as an example, there are over 7200 species points in the data table. In August, if a nature photographer had only an hour before she had to depart for the airport and she desperately wanted to take a picture of an Eastern Cottonmouth (Agkistrodon piscivorus piscivorus), where on the boardwalk would she likely have success? Simply looking through the table for the data to answer that question would be difficult, extremely time-consuming and likely fruitless. However, by posing that query using the GIS software (month and cottonmouth), only the appropriate data points light up. In seconds, you could tell the photographer to go to the stretch between #8 and #10.
Anyone with the free ESRI ArcView Reader software can view and query GIS data. Changes cannot be made to the data, but students can view data, develop questions, and query the data for answers. Recently, we showed this GIS capability to a local high school environmental studies teacher and used our species data as an example of the free resources available from the Audubon Center at Francis Beidler Forest. Even though the staff has over 100 years of combined service at the Francis Beidler Forest and tens of thousands of walks around the boardwalk, we learned something by looking at the example maps we produced.
The first image shows all the recorded Eastern Cottonmouth sightings along the boardwalk. As shown above, the time of year will dictate where along the boardwalk the snakes can be seen, but throughout the year Eastern Cottonmouths can be seen at any location.
We were curious if the same applied for Brown Water Snakes (Nerodia taxispilota). As you can see below, Brown Water Snakes have not been sighted along the backside of the boardwalk (along the swamp's edge) or back toward the nature center.
When we pulled back to include the canoe trail, which is along the main creek channel of the swamp and almost always full of water, there were an abundance of Brown Water Snake sightings and only four Eastern Cottonmouth sightings.
The distance between the east end of the boardwalk and the west end at the swamp's edge is not great. The distance between the end of the canoe trail and the east end of the boardwalk is approximately 300 meters. However, the habitat obviously has different characteristics and the two species of snakes have their preferences.
Looking at the data picture produced by GIS technology allows one to immediately see a pattern that could not be perceived by looking through a table of data. It does tell us why the pattern exists, but is clearly shows its existence and inspires us to investigate.
We'll let you know when we discover the answer!
Images by Mark Musselman
The first image shows a bird's-eye view of the boardwalk here at the Francis Beidler Forest. The nature center and the beginning of the boardwalk are at the upper left. Goodsen Lake is shown at the lower right. North is at the top of the image. The data layers shown include the boardwalk; the species (flora and fauna) sighted over the last few years; the buildings and shelters; the low boardwalk trail; and the property boundaries. Other layers on file include the canoe trail; Project PROTHO data such as nest locations, banding locations, banded bird sightings, and territories; access gates; habitat restoration sites; breeding bird survey plots; etc. What makes GIS technology a powerful tool is the user's ability to view the data separately or in combination with other, sometimes seemingly unrelated, data.
The species data are shown as individual points in the image with each type (plant, mammal, bird, reptile, insect, fish, etc.) shown in a unique color. Though the separate dots are difficult to see in the image, the software allows the user to zoom in. It should be clear that the green dots are the most seen animals. Based on our organization's focus, one could guess correctly that the green dots represent birds.
Using the data shown in the image as an example, there are over 7200 species points in the data table. In August, if a nature photographer had only an hour before she had to depart for the airport and she desperately wanted to take a picture of an Eastern Cottonmouth (Agkistrodon piscivorus piscivorus), where on the boardwalk would she likely have success? Simply looking through the table for the data to answer that question would be difficult, extremely time-consuming and likely fruitless. However, by posing that query using the GIS software (month and cottonmouth), only the appropriate data points light up. In seconds, you could tell the photographer to go to the stretch between #8 and #10.
Anyone with the free ESRI ArcView Reader software can view and query GIS data. Changes cannot be made to the data, but students can view data, develop questions, and query the data for answers. Recently, we showed this GIS capability to a local high school environmental studies teacher and used our species data as an example of the free resources available from the Audubon Center at Francis Beidler Forest. Even though the staff has over 100 years of combined service at the Francis Beidler Forest and tens of thousands of walks around the boardwalk, we learned something by looking at the example maps we produced.
The first image shows all the recorded Eastern Cottonmouth sightings along the boardwalk. As shown above, the time of year will dictate where along the boardwalk the snakes can be seen, but throughout the year Eastern Cottonmouths can be seen at any location.
We were curious if the same applied for Brown Water Snakes (Nerodia taxispilota). As you can see below, Brown Water Snakes have not been sighted along the backside of the boardwalk (along the swamp's edge) or back toward the nature center.
When we pulled back to include the canoe trail, which is along the main creek channel of the swamp and almost always full of water, there were an abundance of Brown Water Snake sightings and only four Eastern Cottonmouth sightings.
The distance between the east end of the boardwalk and the west end at the swamp's edge is not great. The distance between the end of the canoe trail and the east end of the boardwalk is approximately 300 meters. However, the habitat obviously has different characteristics and the two species of snakes have their preferences.
Looking at the data picture produced by GIS technology allows one to immediately see a pattern that could not be perceived by looking through a table of data. It does tell us why the pattern exists, but is clearly shows its existence and inspires us to investigate.
We'll let you know when we discover the answer!
Images by Mark Musselman
Thursday, September 09, 2010
Raccoon Family
Low water at the Audubon Center at Francis Beidler Forest is not as aesthetically pleasing as a full "pool," but it is not a negative for all living things. Obviously, fish and crayfish do not welcome the dropping water levels that shrink the world they occupy, but the dinner bell is ringing long and loud for the predators!
Flocks of juvenile White Ibis (Eudocimus albus) patrol the shallow creeks in search of crayfish. Barred Owls (Strix varia) perch low over the water watching for a crayfish meal to move within talon range. River Otters (Lutra canadensis) supplement their diet of fish and mussels with some of the plentiful crayfish. Raccoons (Procyon lotor) have a wide diet, but they eat a substantial number of...you guessed it, crayfish!
As the water level drops, the crayfish body count rises. Otters, herons, and ibis eat the entire crayfish, so there is no immediate evidence of the meal...the scat evidence arrives later. Owls will remove the claws and swallow the rest whole with the indigestible exoskeleton pieces later regurgitated in a pellet. Raccoons cannot be bothered with the less-meaty portions of the crayfish. They consume the tail like humans at a Maine lobster bar and discard the thorax and claws. Tailless crayfish draped across logs or splayed out on the mud give a gruesome account of the previous night's massacre.
Yesterday as the sun began to set, we came upon a family of Raccoons probing a creek bed with their highly-sensitive paws. Startled by our presence, the female and one kit went south of the boardwalk and two kits went north of the boardwalk. The two kits separated from the family muttered and made sounds like a purring kitten. One started to climb a tree while the other contemplated entering a hollow trunk. Eventually, they found enough courage to pass back under the boardwalk and join mom and their sibling.
Flocks of juvenile White Ibis (Eudocimus albus) patrol the shallow creeks in search of crayfish. Barred Owls (Strix varia) perch low over the water watching for a crayfish meal to move within talon range. River Otters (Lutra canadensis) supplement their diet of fish and mussels with some of the plentiful crayfish. Raccoons (Procyon lotor) have a wide diet, but they eat a substantial number of...you guessed it, crayfish!
As the water level drops, the crayfish body count rises. Otters, herons, and ibis eat the entire crayfish, so there is no immediate evidence of the meal...the scat evidence arrives later. Owls will remove the claws and swallow the rest whole with the indigestible exoskeleton pieces later regurgitated in a pellet. Raccoons cannot be bothered with the less-meaty portions of the crayfish. They consume the tail like humans at a Maine lobster bar and discard the thorax and claws. Tailless crayfish draped across logs or splayed out on the mud give a gruesome account of the previous night's massacre.
Yesterday as the sun began to set, we came upon a family of Raccoons probing a creek bed with their highly-sensitive paws. Startled by our presence, the female and one kit went south of the boardwalk and two kits went north of the boardwalk. The two kits separated from the family muttered and made sounds like a purring kitten. One started to climb a tree while the other contemplated entering a hollow trunk. Eventually, they found enough courage to pass back under the boardwalk and join mom and their sibling.
Once again a family unit, they returned to moving up the creek in search of a meal.
It won't be crayfish, but we are ready for a meal too!
Images by Mark Musselman
Tuesday, September 07, 2010
LIfe and Death in the Swamp
At the Audubon Center at Francis Beidler Forest, there were several examples of life's circular movement. The discovery of a Polyphemus Moth (Antheraea plolyphemus) caterpillar along the boardwalk's handrail was matched with yesterday's photographs of adult Polyphemus Moths. Although caterpillars dine on a variety of trees, including dogwoods, elms, hickories, maples, oaks and willows, the adults do not eat. Once the adults emerge, males and females spend their first day finding each other. Females emit pheromones, which a male can detect miles away. Once mating has occurred, the female will spend the rest of her life laying eggs. Adults only live for a few days.
We were not on the boardwalk hunting caterpillars. The odor of death had been detected near the boardwalk at #112 and the remains of a deer could be seen ten meters to the north.
Upon closer inspection, we saw that what at a distance looked like gray fur was actually a living, writhing mass of maggots. The maggots are likely from the genus Lucilia, which contains species like the Green Bottle Fly (Lucilia sericata), although American Carrion Beetles (Necrophila americana ) were also on the scene. These flies can be found around the world and they specialize in laying eggs in and eating dead or decaying flesh, often within hours of the organism's death. The larvae transition through three instars on a predictable schedule based on the temperature of the environment and amount of disturbance. Therefore, these insects are used by forensic scientists to estimate the time of death of a corpse and whether or not the corpse was disturbed.
When the images of the maggots were taken, they covered the majority of the fawn's body and could be easily heard as they moved and ate. There was little left for any larger scavengers. However, that did not prevent the vultures, both black and turkey, from finding the carrion two hours later below the forest's thick canopy. The vultures' stay was brief due to the lack of suitably-sized portions. During their inspection, the vultures did move the deer's remains and dislodged many of the maggots.
No word yet on whether the maggots separated from the carcass were able to reestablish contact with their meal.
Images by Mark Musselman
We were not on the boardwalk hunting caterpillars. The odor of death had been detected near the boardwalk at #112 and the remains of a deer could be seen ten meters to the north.
When the images of the maggots were taken, they covered the majority of the fawn's body and could be easily heard as they moved and ate. There was little left for any larger scavengers. However, that did not prevent the vultures, both black and turkey, from finding the carrion two hours later below the forest's thick canopy. The vultures' stay was brief due to the lack of suitably-sized portions. During their inspection, the vultures did move the deer's remains and dislodged many of the maggots.
No word yet on whether the maggots separated from the carcass were able to reestablish contact with their meal.
Images by Mark Musselman
Thursday, September 02, 2010
Canoe Trips
Although the water level in the swamp continues to drop, the rain in the previous weeks has kept sufficient water in Four Holes Swamp to allow the Audubon Center at Francis Beidler Forest to run canoe trips. Until the water drops below the "canoeable" level, we will be running canoe trips from 9am-12pm on Saturdays. Reservations are required (843-462-2150) and the cost is $30 for adults and $15 for children.
A private canoe trip was conducted today. We saw Yellow-crowned Night Herons, Yellow-bellied Sliders and American Alligators in Mallard Lake. Once on the trail, we saw River Frogs, a Great Blue Heron, and a Brown Water Snake sunning in a patch of poison ivy. In the distance, we heard a Barred Owl, Pileated Woodpeckers, Northern Parula Warblers, American Crows, and a Red-shouldered Hawk.
Images by Mark Musselman
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