The misadventures of an urban naturalist

Published on ecoRI news

Ever since I moved to Providence from the northwoods my daily walking has taken me to the cemeteries of the East Side.  I still walk frequently in the Swan Point Cemetery but ever since a neighborhood delegation convinced the Parks Department to quit locking the pedestrian entrances to the North Burial Ground I have spend much time there looking at the two ponds.  In the NBG the larger pond, the one right below the esker, is a treasure trove of wildlife.  There are fish, turtles (at least 2 kinds) Bullfrogs, a variety of waterbirds (ducks, geese,Green herons, Night Herons, Great Blue Herons, Kingfishers, Cormorants) muskrats and otters.  Swan Point provides an occasional opportunity to see large and charismatic wildlife such as Bald Eagles or a flock of 15 Great Blue Herons, but day in and day out if you need a small wildlife fix, the pond at the Burial Ground will show you something almost every day.
The bigger pond will be included in this tale of misadventure and discovery, but the scene of the crime is actually a little drainage swale just below the maintenance building.  It has water in it most of the time, but does go dry when we hit a long dry spell.  It is about 50 ft by 75 ft, maybe 2ft deep at its deepest point.  I had walked in the Burial Ground occasionally prior to its unlocking, but had no memories of the drainage swale.
But several years ago some time in May or June, (I have no recollection of the date, only the wonder) I was walking by the pond ( which is how one might normally think of it until they checked out the drainage system more carefully and realized it was man made) looking at the water and saw these little black tadpoles swimming around in the water.  It was the first tadpoles I had seen in years, and most definitely the first opportunity for the study of tadpoles since I had studied evolution and could understand what I was looking at.
For the few weeks in the late spring and early summer that they were turning from tadpole to ( and here the misadventure begins) frog  I watched nearly daily.  Actually I did not know what kind of tadpoles they were, did not know you could look at tadpole pictures to identify them, but figured when they turned to frogs I would be able to identify them.
There were thousands of them, and mostly they swam about the shallow water right offshore in plain sight.  I brought my bird watching scope and had some very good viewing.  Eventually i saw legs and they turned to frogs in early July.  I looked carefully at some before they hopped away.  They were mostly gray with dark markings on the back.  On line I looked at frog pictures and thought they were Gray Tree Frogs.  I gave it no other thought other than that is what I started calling them, while I awaited the next spring so I could watch again and learn more.
The second year I saw them early, watched all the way through, learned that this bunch were mating repeatedly with tadpoles showing up in cohorts in May and June. Again the first week of July, they were gone.  I also realized that the ease of observation might just make it a great place for both educational and video purposes.  I continued my observations, starting to think about recording the dates of first sightings and last, began to understand the waves of maturation as likely resulting from successive nights of mating, and began to look for some sort of program for young teens who might be interested in creating a video.  Luddite that i am it was hard to imagine me getting and figuring out how to use a camera.  So I figured some program for teens might have one or two that would be interested in such a thing.  I still have not found them.
My third year of observation, while I was still hoping some teenagers would work with me (I continue to offer the opportunity for teenagers in my neighborhood) I actually recorded the date I first saw tadpoles, May 12.   In retrospect I realize I paid little attention to pond dynamics other than knowing it would go dry in a drought and watching it empty and fill with the weather.   One highlight of the year was bringing my great niece down to the pond for her first look at tadpoles.  For that we netted a few, looked at them briefly, then put them back and netted a new crop.  They are so easy to net that even a three year old could do it.  She was gentle and practiced catch and release.  I also spent a bit more energy watching the vegetation in the pond, and realized that about the time the tree frogs were hopping away the vegetation in the pond was starting to get thick and eventually became so thick that you could not see into the pond to watch anything.
This third year I also became aware that as the Tree Frogs were leaving, a new crop of tadpoles was becoming visible.  Again my ignorance showed and I assumed that since there were bullfrogs not very far away, and that as the pond did not go dry every year Bullfrogs might be fooled into trying live there on occasional dispersals from crowded ponds.  I assumed they were bullfrog tadpoles.  Between the vegetation and the pond going dry I saw no more of the new tadpoles after mid July and thought I might find out more the next year.
After two years of looking for a program to work with on the video I decided it was time to do it myself.  That and the Rhode Island Rivers Council suggested that Friends of the Moshassuck to do more than work on its experimental forest every year. So FOTM applied for a few hundred dollars in our annual Rivers Council grant application to make a video on the development of Gray Tree Frog tadpoles from first appearance to hopping up the hill and away from the pond. The request was funded and I jumped in along with my friend and fellow Friends of the Moshassuck board member Michael Bradlee.  Thank you RI Rivers Council for your support of this project.
I got a used JVC camera up on Hope St, It spent weeks on my desk while I figured out how to find the owners manual and reading it.  Eventually, some time in early March, I just started taking it outside and turning it on.  I then spent two weeks recording and deleting strange shots of the ground, monologues, and experiments with focusing and magnification, and then figured out how to get into imovie.   I started collecting video of the two ponds in the North Burial Ground towards the end of March 2013 and vowed to learn to edit them.  I eventually learned you can do primitive editing simply by copying, pasting, deleting, and that I can do.  I also learned about slow motion, and I have learned much about tadpole locomotion by watching slowed down swimming and jumping.   I still can not do captions, voice overs, music or anything else, but it was enough to get started.
From the start it was clear to me that while the grant was for a tadpole video, it made sense to record all of the different wildlife  in the Burial Ground.  Early on there were the birds and much footage of efforts to get birds in focus and keep them in the screen has been deleted.  I continue capturing birds in pixels and am looking to eventually produce a video collage of the birds of the NBG.  I am slightly more adept today than I was in March but actually just became comfortable with shooting and shooting and getting 5 usable seconds.  Under those standards I even have a few shots of swifts and the red tail hawks.
When it became warm and sunny in April the bigger pond came alive with Painted Turtles and Bullfrogs.  I have been tracking the turtles and Bullfrogs over the last few years as well as the tadpoles of the little pond.  Two years ago I regularly counted 9 turtles on the morning sunning log, and last year there were 12.  This year I have seen as many as 14 at a time during the spring peak.  The turtles taught me much about video production.  My tendency is to futz and the turtles reminded me to set the camera, get the turtles in focus, hit record and walk away.  The magnification and distance meant that with the naked eye I could only see the outline of what was going on, and on the little screen that shows you what you are filming it is hard to see much, so all of the interesting turtle behavior observed is the result of reviewing my footage after the fact.  Do not know what I will do with it all, turtles can be pretty boring and immobile for long stretches, but there is some interesting footage and I expect I will find a few minutes of action to show when I get to turtle videos.  On May 12 I I learned how easy it is to finish up a video in imovie (click on finish)  and post it on to youtube (click on share) . I created the moshassuckcritters youtube channel and posted small snippets of a bullfrog sitting in the pond, some turtles sunning, and calling frogs.  The Bullfrog footage continues to be collected, and I will eventually produce a Bullfrog video.
While I had gotten in the habit over the last few years of walking in the Burial Ground, even at night, I had not taken to walking late enough to see the frog matings in the long days of May and June.  But with video project underway Michael Bradlee and i spent a number of evenings trying to get pictures of mating frogs (only one quick shot that is included in the Fowler’s Toad development video) and recording lots of calling. Mating took place on multiple nights when conditions were favorable.  I started posting short snippets of calls right away.  It is only as i now go through the material making videos from the raw footage that I have heard the clear distinction between the calls of the frogs and the toads.  Because we assumed we knew what we were listening to (tree frogs), we did not do our homework, though i listened to some tree frog calls on the web and what we heard seemed to match up. Of course this being a misadventure I was totally confused about what we had in the little pond,  Sometimes it sounded like we were hearing two different critters, but we were never sure, and just assumed tree frogs were multi tonal.  As I was writing this, and simultaneously working on putting the Gray Tree Frog Development video together, I listened to two sets of calling one right after the other.  The calls were very distinct and i realized for the first time I could  tell which calls were which.    Though I checked with some experts before totally believing it. Clearly this is something I am going to have to pay much more attention to next spring when I do this again.
Beginning on June 5 little black critters filled the little pond, thousands of them over the next few weeks.  Assuming the were Tree Frogs I posted videos, did interviews, wrote blog posts about them.  In their early stage they remind me of pelagic shellfish, on steroids.  I often think of them as harried commuters living in tadpole cities during the morning commute, often with a predominant direction.  It is a sight to behold, these little critters going every which way, bumping into each other, stopping here and there then moving on.   Over the last few years it is the mad rush of the tadpoles swimming that has stuck in my mind the most.  But this year i was actually recording things and reviewing them and a new picture began to emerge.  Turns out the pelagic stage lasts barely a week, at which point they start to settle down in the vegetation and eat.  They are still hyper, moving a lot, but staying on the vegetation and eating much of the time.  Most tadpoles eat bacteria on the plants in the water, very different fare from the insects and other small creatures they eat after transformation.  I have included video of Fowlers toad tadpoles grazing on what grows on the grass.
The pond is open water in the cold weather, but as the pond heats up an amazing array of plants spring up, and they cover the entire surface of the pond by late June.  I noticed this phenomenon last year, but this year I paid much more attention.  By June 18 it was starting to get very difficult to get clear shots into the water of the tadpoles hidden as they were in the bottom vegetation, and the flowering plants above the surface began covering the entire pond with their leaves.  June 22 was the last day i could get a clear shot of anything in the pond, and that was the day I made my first pictures of the second round of tadpoles in the pond.
Turns out I had focused the camera on the water, turned it on, and then turned to talk to a colleague who had shown up.  It was only later, many days later, when i got a chance to look at the footage that I realized what I had captured.   The 23rd I returned to the pond with my great niece for the second year in a row and netted tadpoles for her to look at and to video.  It was then I became aware of the diversity in the pond, and events were set off that eventually turned the misadventures in taxonomy into a much more accurate picture.  In addition to catching little black tadpoles in all stages, no legs, two legs, four legs, and the first frogs of the season, we caught a few tadpoles with green skin a large flat tail and a golden disk, the ones I had seen the year before and thought were bullfrogs.
By this time I had learned that there are tadpole identification guides and I checked out a few on line.  I assumed it was bullfrogs, maybe with a few coming over from the big pond a few hundred yards away, but that did not seem quite right looking at the pictures.  They looked the most like Gray Tree Frogs, but i was very skeptical because I thought the little black tadpoles turned into Tree Frogs.  So I posted a video clip and started asking my colleagues at DEM, RINHS, and assorted places what they were.  I received I do not know answers, and some guesses as good as mine, but eventually I was connected to Chris Raithel of the RI Department of Environmental Management and Peter Paton at URI.  Peter clearly identified the new tadpoles as Gray Tree Frogs.  When i had absorbed that information I asked what were these little black tadpoles that turned into gray frogs.  The original word came back as American Toads, which was quickly updated to Fowler’s Toads.  I realized how big a misadventure i had been on for two years, though no real harm done, I needed to correct everything.  So I fixed the titles and write ups on the videos and fixed some of the writing about frogs on my blog.
The use of the net to catch tadpoles and froglets for videoing on June 23 changed the project dramatically, and allowed it to go forward at a time when it was impossible to video into the pond.  I quickly developed a methodology that got me as clear pictures as an amateur like me was going to get , that also allowed the tadpoles to have water  and to get them back into the pond safely.  This allowed me to capture much more detail in the development of the legs, and the sequences I have of very tiny legs in the Tree Frogs are not matched in the pictures I have of developing Toads.  I have a few glimpses of toads in slow motion showing what might be the early stages leg development, but nothing very clear until videoing netted tadpoles on June 23.  What I did get on the toads is cool pictures of them in the two and 4 legged stages.  The two legged stage is still very much water adapted. When the toads were in my hand or the net trying to move using 2 legs essentially jammed their faces into the substrate and they only moved by thrashing around.  Once front legs develop they start to walk and it is this four legged stage while still having a large tail, that i found the most interesting.  The developing toads looked like little dinosaurs or lizards, while the other stages look only like amphibians.
For the next few weeks the number of toad tadpoles caught each day went down while occasionally there would be an eruption of toadlets as the next mating night batch finished their development and left the pond.  I included a bit of hopping away to end the toad video.
In early July the last of the Fowler’s Toads left the scene, leaving Gray Tree Frog Tadpoles hiding among the vegetation in the shallows.   I thought I developed a search profile that allowed me to consistently catch tadpoles, but as there were many fewer tree frog tadpoles than Toad tadpoles, I was only able to catch a few each day.  These I videoed in a small plastic container with a bit of water, an arrangement that i intend to upgrade next year.  With this set up I was able to intensively study the leg development in the Tree Frogs, which was the goal of the project all along, and i think the video of  Tree Frog development covers the development of rear legs quite well.  I am not quite sure about the development of forelegs and how quickly it goes.  I did not catch those stages at all, Nothing today, full blown tomorrow.  Consistently.  I am guessing it happens very quickly.  One of my favorite pictures of the whole project is the tree frog with 4 legs and a big tale climbing the plastic container.  I included both normal speed and slow motion of that clip in the video and in slow mo it is a treat.
The netting program also gave me a chance to observe the insects and other invertebrates in the water, a collection of footage I will eventually edit and release, and I got the idea to shoot video of the flying insects as well and have footage of dragonflies, bees, and other assorted flyers.  Watching the bees work the purple flowers of the water plants was a treat that only the camera allowed me to enjoy.
Three intensive months of filming are now done, and among the 47 videos now on moshassuckcritters are videos on Fowlers Toad tadpole development and Gray Tree Frog development showing all of the stages.   Comments appreciated.  It has been an educational experience, and I look forward to doing it again next year.
 Fowler’s Toad video


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