Spring is in the air…. Uh, I mean water!

It was the sound that first attracted my attention. Initially, I thought that it sounded like a flock of birds, but as I approached a pond, I realized that was not the case. The almost chirruping sound didn’t fit with any frogs I had heard before. As I scanned the scene before, my roving vision finally alit on a small section of brownish water dappled with green algae and stalks of dead reeds – there were moving bumps there. When I came closer, I finally realized that it was a mass of writhing and continually moving toads, engaged in what resembled a bit of a battle. It was actually what could be called a mating contest. (Click on a photo to see it larger; then arrow back to return to blog.)

The sound made by the male Eastern American toad (Anaxyrus americanus americanus) when he is ready to breed has been likened to an old-fashioned ringing telephone. It can last from 6 to 30 seconds and when multiple toads are calling at the same time, they create a very loud and penetrating “concert”. It doesn’t sound like a phone to me; you can judge by listening to the video.

I only saw a couple of the toads with inflated throat sacs. The sound was very loud, however, and the water was roiling with moving heads topped by periscope eyes, warty bodies and thrashing legs.

Before examining how the toads were going about their reproductive endeavor, a little biology lesson. Toads are a sub-group of frogs; while most frogs have moist skin, toads generally have drier and wartier skins. They vary greatly in color, including shades of yellow, brown, black and red, and may be speckled or have solid hues. The skin color can also change in response to stress, temperature, humidity and habitat.

 

American toads have two glands at the top of their head behind the eye crest. These are parotid glands that produce a neurotoxin, bufotoxin, which can sicken and even kill a predator. The milky substance can produce skin irritation in human beings and can be dangerous to smaller mammals (like dogs).

 

 

Like birds, toads have nictitating membranes, transparent eyelids that help protect the eye. They sometimes raise the nictitating membrane half-way so that they retain sharper vision.

 

 

Toads actually spend a lot of their lives on dry land, eating insects as well as worms, slugs and other small invertebrates. A particularly fascinating fact is that they use their eyeballs to help swallow food – when they ingest their prey, the eyeballs sink down into their mouth and help push the food down their throats!!!

At times, they created little whirlpools as they bumped up against one another or tried to mount a neighbor.

 

 

Sometimes, a large female with a smaller male atop her would rest quietly under water, apparently trying to avoid notice. This strategy did not always work, however, and sometimes one or more other males would try to join the pair already in amplexus (i.e., when the male grasps the female with his front legs and fertilizes the eggs as she releases them from her body)..

The female toad ejects her eggs in two strings, which are immediately fertilized by a nearby male spurting out a stream of sperm. (Frogs lay their eggs in clusters.) Tadpoles will emerge from the eggs within 2–14 days and reach adulthood within 50–65 days. They become sexually mature at 2-3 years.

In one case, I developed a real sympathy for a particularly large female. She had a small male astride her who resembled her in coloring and they looked to be peacefully joined. Then another male spotted them and he launched a sneak attack, trying to usurp the position of her already-present suitor. The first male clung on tightly.

No. 1 pushed No. 2 away with a hind leg again and again.

In the meantime, a great blue heron (Ardea herodius) who had been feeding on the other side of the pond, made its way over to the site of toad frenzy. S/he had been eating small fish and amphibians.

I thought the heron would plunge into the midst of the numerous toads for an easy meal, but instead the bird looked around and then skirted the group, veering away to the shoreline. Perhaps some instinct made the heron avoid the group during a reproductive event? Or s/he was put off by the vigorous activity of the potential prey?

A second rival toad then joined the first, who was still trying to get the original mating male out of the way. Eventually, a third, fourth and yet another male joined the group and the poor female was weighted down by 5 – FIVE! – male toads all vying for the prime spot on her back. Often her head was pushed down under water.

The first male clung on with great determination, often being pushed down under water as well as the other males piled on. He was NOT going to give up.

Ms Toad did not like this state of affairs. She laboriously began moving from a deeper spot in the pond to the pond’s edge. This was a slow process, made difficult by the clinging crowd who must have weighed a good deal as a group.

I thought she might be trying to get to more shallow water so the toad “knot” would not keep her submerged. Toads can breathe under water like frogs because they can absorb oxygen through their skin. They do have lungs, however, and if these fill with water, they can drown. A fellow Facebook nature lover told me that she had seen expired female toads with males still clinging to them. A toad knot can therefore unfortunately result in maternal mortality – the demise of a mother giving birth (to several thousand eggs; most of the tadpoles do not survive).

I soon left the scene after Ms Toad had reached the side of the pond and could keep her head above water. It was noticeable that her throat pouch was inflating and deflating – perhaps she was breathing deeply to compensate for lack of oxygen when she had to suffer a submerged head due to the over-amorous males.

 

Inhale!                                                                  Exhale!

I know I am anthropomorphizing, but I do believe that she likely felt the amphibian equivalent of relief and was looking forward to the end of that day!

My pond and the cycle of life

Undergoing cardiology exams can bring up thoughts of mortality and a life lived; perhaps they also made me more attentive to the cycle of life in my yard, particularly in the vicinity of my backyard pond.

Several years ago, a local garden center went out of business and they had a 175-gallon black plastic pond for sale. It was a good deal, so I invested in it and then had to dig a large hole in the rocky Piedmont clay ground of my backyard (with a bit of help from a neighbor teen). At a certain point, the ground was so hard we couldn’t penetrate it with shovels so the pond now sits a bit above ground level; the rocks I piled up around it have offered a home to Eastern chipmunks (Tamias striatus).

 

I transferred some of my beautiful koi and goldfish from a smaller pond, only to have a great blue heron (Ardea herodias) come by to clean them all out.

On the recommendation of the garden center staff, I had positioned a heron statue by the pond – they said herons don’t like competition, so the intruder would keep flying when s/he saw the one by the pond. It didn’t take long for the bird to figure out the stationary bird was not real, however.

After the heron had eaten all the koi and goldfish, I still had some tiny baby fish. At first, I thought they were from my now deceased koi but apparently the intruder heron had had fish eggs on its feet from a nearby natural pond and left them behind. So for a time, I had unidentified native fish in the pond. They were extremely shy, however, and I only got a brief look at them when they surfaced early in the morning; as soon as I came near, they dove down under the water plants (no good photos).

Then some green frogs (Lithobates clamitus) moved in this past summer and ended up being extremely prolific reproducers. Before I realized it, there were at least 500 tadpoles in the pond!! They were eating the fish food and at the same time I noticed that I wasn’t seeing the fish at all anymore. Going online, I found out that tadpoles will eat fish – their sheer numbers had to have spelled doom for the fish.

 

 

I collected lots of the tadpoles, gave some to a friend for her water feature and released hundreds into the local creek (they are native animals after all). A few of the tadpoles grew into frogs and the pond became a residence for some very loud croakers.

 

  

The next chapter in the story came a couple days ago. I had seen a pair of red-shouldered hawks (Buteo lineatus) visiting my yard recently. I thought they were after the chipmunks, numerous squirrels and songbirds populating the area. The other day, however, one hawk took up a position in the crepe myrtle tree next to the pond and just sat there calmly not bothering with any of those creatures. Numerous Northern cardinals (Cardinalis cardinalis) perched in the tree above her and many other species of birds were at the nearby feeders;  none of them were concerned at all with the hawk’s presence. The squirrels didn’t seem perturbed either.

She sat fairly still and I took some photos through my kitchen window. Then I ventured out into the backyard, sure she would take off as I left the porch steps. But Ms. Hawk just sat there, sometimes stretching a leg or engaging in a little grooming.

     

   

Occasionally, she looked up but often her gaze was fixed on the area around the pond.

She would stare intently down at the ground – I thought she might have spotted one of the pond chipmunks.

Then after a while, I noticed her shifting her stance – suddenly she plopped down into the pond with spread wings. It happened too fast for me to get out from behind dried plants to get a good photo, so I watched as she climbed out of the pond. Then it became apparent what she had been hunting – she had caught one of the green frogs.

  

It looked like she bit its head to kill it as soon as she got on dry land; the frog wasn’t moving.

Then she spent time ruffling and shaking out her feathers which had gotten a good soaking.

She spent a little time looking around and then abruptly took off with her prize, closely followed by another red-shouldered hawk who suddenly swooped in.

He chased her but she got away with her meal and he ended up sitting in a neighbor’s tree, somewhat disgruntled with his failed thievery attempt.

  

Ms. Hawk returned yesterday and spent quite a bit of time in a high tree surveying the yard and gazing down at the ground. Red-shouldered hawks sometimes eat birds, such as sparrows, doves and starlings (which are all numerous around my feeders) but more often they go after snakes, mice, toads, frogs, lizards and small mammals such as voles and chipmunks. They will also eat insects and earthworms. Since I’m leaving the leaf litter, there are undoubtedly more insects hiding there than in neighboring yards. I’m not sure what Ms. Hawk is seeking in my yard, but I hope she doesn’t get all the pond frogs. In any event, I’m sure new ones will find the water in the spring and in the meantime, I have a beautiful bird of prey to watch this winter.

An evening at Bolin Creek

After a day waiting for four bluebirds to fledge (next blog!) and a health-care appointment, I decided to forego some chores and instead to spend some time at a bridge over Bolin Creek, a waterway in the local Carolina North Forest which belongs to the University of North Carolina. My naturalist friend Mary discovered that this spot is a favorite bathing spot for birds in the late afternoon and evening. Since the weather forecasters predicted rain most afternoons this week, I decided to make a quick foray there while I had the chance. I knew that photographing the wildlife could be difficult as the sky was dull, overcast and we were expecting a downpour but I was up for the challenge. And once in a while a bit of brightness emerged from behind the clouds to give me some encouragement.

At first, it seemed very quiet – no bird song or buzzing insects; I thought perhaps everyone was hunkering down in anticipation of a coming rainstorm. But then the sky lightened a bit and a handsome robber fly (Promachus) alighted on a nearby leaf. I think this is a red-footed cannibal fly; these insects look like little old men to me.

 

 

A little while later, there were suddenly three avian visitors. The female Eastern towhee (Pipilo erythrophthalmus) was the first to take a bath.

     

 

The blue-gray gnatcatcher (Polioptila caerulea) didn’t go to the water but flitted overhead.

 

The first of two American redstarts (Setophaga ruticilla) also hopped from branch to branch but eventually ducked behind some rocks to bathe.

A pair of damselflies hung out on the stream rocks; the blue-tipped dancer’s (Argia tibialis) dark purple made it look almost black in the twilight.

 

 

Then a beautiful female hooded warbler (Setophaga citrina) came by for a bath. Her golden feathers shone in the dark foliage and against the stream rocks.

 

 

 

A pair of gray catbirds (Dumetella carolinensis) came together but only one entered the stream for a thorough drenching of its plumage.

 

 

 

   

The redstarts returned but stayed on the branches as the daylight began leaking away.

A few other birds were in the vicinity but didn’t come near: American crows, Northern cardinals, a common grackle and two yellow-billed cuckoos. My visit ended when the sky really darkened — I started down the path in an effort to reach my car before the rain began. A Southern leopard frog (Lithobates sphenocephalus) crossed in front of me and paused in the grass, enabling me to get a quick portrait. And then a nettle of beautiful violet color called out for a photo, too. I made it to the car just as the first raindrops fell. Quite an enjoyable impromptu photography session!

Pulling privet, banishing buckthorn and mimicking Mother Nature

The (somewhat) varied life of a Mason Farm Biological Reserve volunteer

sign-dk7a3365-maria-de-bruyn-res

Today marks the third anniversary for my work as a Green Dragon – volunteers who help maintain the 367-acre Mason Farm Biological Reserve in Chapel Hill, North Carolina. On Tuesdays, a small group gathers to carry out tasks assigned by Neville, who is the Land Manager for this and two other preserves managed by the North Carolina Botanical Garden/UNC.

neville-img_4702-maria-de-bruyn-res

Neville, string-trimming Japanese stiltgrass (Microstegium vimineum)

winter-wren-i77a8901-maria-de-bruynWhile we work, we can listen to the songs and calls of lovely birds, like the winter wren (Troglodytes hiemalis), and if we’re lucky, we can see wildlife like painted turtles, raccoons, opossums and coyotes (Canis latrans).

coyote-i77a8913-maria-de-bruyn-res

 

 

 

 

 

Being outdoors and helping keep the Reserve a peaceful and beautiful area for research and enjoyment of the natural world provides me with a feeling of civic contribution, as well as satisfaction, chances for discovery and learning, and well-being. So I’d like to share with you a bit of what we do in a lengthier blog than usual.

sign-img_0076-maria-de-bruyn-res sign-dk7a2339-maria-de-bruyn-res

wisteria-cutting-img_0427-maria-de-bruyn-resOne of our major tasks is helping make a dent in the eradication process for invasive plants. Some have found their way to the Reserve through natural dispersal mechanisms (seeds carried by the wind and wildlife), while others were unfortunately introduced by humans who didn’t know at the time just how destructive the plants would become in overshadowing native vegetation. Cutting down Chinese and Japanese wisteria vines (Wisteria sinensis, W. floribunda) is a recurrent job.

Some invasives are really beautiful and it’s easy to see why they are still sold in some garden shops, like oriental bittersweet (Celastrus orbiculatus) and porcelain berry (Ampelopsis glandulosa); they are really attractive plants – nevertheless, we remove them when feasible. Autumn and thorny olive (Elaeagnus umbellata and E. pungens) are two others that grow as vines or shrubs.

oriental-bittersweet-8-oriental-bittersweet-img_5343m-de-bruyn-signed   porcelainberry-img_0739-2maria-de-bruyn

buckthorn-i77a2455-maria-de-bruyn-signed-resAnother botanical foe is buckthorn (Rhamnus species), a shrub which can grow into a small tree when unchecked. It has nasty thorns which can pierce clothing and shoes and when it gets older and larger, a weed wrench and extra manpower may be needed to get it out of the ground. On the other hand, pulling up the “baby” buckthorns, especially after rain, can be much easier, though unkind work for your back.

buckthorn-img_5724-maria-de-bruyn-res

pete-img_1764-maria-de-bruyn-res  buckthorn-img_4403-maria-de-bruyn-signed-res

Volunteer Pete wields a weed wrench; the small buckthorns can be pulled by hand

marbled-salamander-img_3320maria-de-bruyn-resWhen digging holes into some areas, you may come upon salamanders – this female marbled salamander (Ambystoma opacum) was guarding her eggs when we uncovered her (and quickly covered her again).

The buckthorn produces prolific black berries which are a great favorite of the cedar waxwings (Bombycilla cedrorum) – flocks will descend to enjoy the sweet treat.

cedar-waxwing-i77a6144-maria-de-bruyn-res   cedar-waxwing-i77a6020-maria-de-bruyn-res

The cedar waxwings also really like privet (Ligustrum sinense and L. japonicum), which produces numerous black berries a little smaller than the buckthorn. The privet also produces many offspring but when they are very young, they are quite easy to pull up. The privets that grow into trees, however, pose the same challenges as the large buckthorns, calling for multiplied manpower to extract them from the ground and resulting in exhaltation when success is achieved.

privet-img_1234-maria-de-bruyn-res privet-img_1233-maria-de-bruyn-res

privet-img_1262-maria-de-bruyn-res

buckthorn-img_5597-maria-de-bruyn-res

 

While working on invasive eradication, we often come upon smaller wildlife, like American toads (Anaxyrus americanus, formerly Bufo americanus), bullfrogs (Lithobates catesbeianus), green and gray tree frogs (Hyla cinereal and H. chrysoscelis/versicolor), spring peepers (Pseudacris crucifer) and rat snakes (Pantherophis obsoletus).

american-toad-img_0013-maria-de-bruyn-res  bullfrog-img_0226-maria-de-bruyn-res

buckthorn-img_4403-maria-de-bruyn-signed-res  frog-i77a3959-maria-de-bruyn-res

copes-gray-tree-frog-img_6145-maria-de-bruyn-res   spring-peeper-img_4391-maria-de-bruyn-res

rat-snake-img_3470-maria-de-bruyn-res

The many brush piles dotting the landscape in the Reserve, both in wooded areas and fields, are the result of our labors – providing birds and small animals with ready-made homes and hiding places.

brush-piles-img_4394-maria-de-bruyn-res

Volunteer Giles and Neville pile up privet and buckthorn

A second major task is planting native plants in various areas of the Reserve – seedlings and young plants are provided by the Botanical Garden and Land Manager and may include flowering species such as Hibiscus and cardinal flowers (Lobelia cardinalis), fruiting shrubs like common elderberry (Sambucus nigra Canadensis), and varied grasses.

grasses-are-hollow-img_0274maria-de-bruyn-signed-res   planting-img_0217maria-de-bruyn-res

bill-resting-sore-back-img_0284maria-de-bruyn-signedWhen we do this in summer, the temperatures can get quite high early in the day; water breaks are welcome, as shown by Mason Farm Green Dragon supreme – Bill, who has been volunteering since 2004!

We put in flags to mark the new plantings in case they will need some watering to thrive. When the weather is hotter and drier, watering takes place right away to give the young vegetation a better chance at survival. It’s a real pleasure to see the plants take hold and flower!

grasses-img_1282-maria-de-bruyn-signed-res   aaron-watering-asters-img_0277maria-de-bruyn-signed

flame-i77a0237-maria-de-bruyn-resSome plants are fire-dependent, meaning their environment must be burned with some regularity if they are to survive and thrive.

Prescribed burns are therefore done at Mason Farm to mimic the natural fires which took place centuries ago before development took over many areas. Woods and fields are burned every few years and great attention is paid to the weather, taking care that no high winds are predicted that could carry embers far away to start fires in unwanted areas. The Green Dragons helped clear fire lines last week for a recent burn – raking away leaves and twigs and bark from areas where the fire will normally die out.

flame-i77a0238-maria-de-bruyn-res flame-i77a0239-maria-de-bruyn-res

neville-i77a0232-maria-de-bruyn-resMembers of the fire team receive instructions on their roles – the fire starters ignite the leaves and grasses in stages, pausing to see how fast the fire is moving and how the wind is blowing.

 

 

flame-i77a0239-maria-de-bruyn-res   johnny-i77a0244-maria-de-bruyn-res

Several people will serve as spotters, watching the fire lines to ensure that any escaping embers are put out and some team members clear areas around trees and snags that will be protected against burning (e.g., because they provide homes for woodpeckers).

fire-team-img_1400-maria-de-bruyn-res

Where the leaf litter is not 100% dry, some areas will burn and others will remain untouched.

flame-i77a0246-maria-de-bruyn-res

Dry grasses can catch quickly and the spreading fire generates intense heat as the flames spread rapidly across a field.

i77a0266-maria-de-bruyn-res  ignition-img_1404-maria-de-bruyn-res

flame-i77a0276-maria-de-bruyn-res  flame-i77a0274-maria-de-bruyn-res

broad-tipped-conehead-katydid-neoconocephalus-triops-img_1403-maria-de-bruyn-resMy concern is always that not all animals will make it out in time. Fellow volunteer Giles spotted a broad-tipped conehead katydid (Neoconocephalus triops), which he carried to a safe spot. I hope that the Eastern box turtles (Terrapene carolina carolina) have dug down deeply enough to be unharmed by the spreading fire. We saw grasshoppers and bugs fleeing the field being burned this past week and I was happy to see a pair of hispid cotton rats (Sigmodon hispidus) rush out.

eastern-box-turtle-img_4536-maria-de-bruyn-res  eastern-box-turtle-img_5682-maria-de-bruyn-res

After the fire is mostly burned out, the team walks the edges to tamp out still burning places. The next day, the woods and field look mostly gray, black and sere but experience has taught me that in a few weeks they will begin turning green again.

neville-i77a0286-maria-de-bruyn-res     fire-team-i77a0282-maria-de-bruyn-res

There is one more task we carry out which is less frequent but also important – aiding in construction and some clean-up in the Reserve. When funding was received for a boardwalk to make a bog area more accessible after rain, volunteers associated with the Botanical Garden and New Hope Audubon Society as well as Green Dragons built the sections of the board walk, transported them to the site and installed them.

img_8306maria-de-bruyn-res  img_8549maria-de-bruyn-res

flooding-img_1936-maria-de-bruyn-resVisitors were very happy with the new walkway but it turned out that the flooding which occurs when Morgan Creek overflows its banks with heavy rains can sometimes be strong enough to lift up boardwalk sections, necessitating repairs. When funds are available, a new solution will be sought to hold the boardwalk more permanently in place.

 

mason-farm-img_4883-maria-de-bruyn-res mason-farm-img_4877-maria-de-bruyn-res

The researchers who make “temporary” structures when conducting their studies (e.g., bird blinds, platforms, etc.) unfortunately do not always remove these when their research is done. When time permits, we have helped clear away some of this garbage. We also helped repair a sign and the entry road and parking lot after flooding.

bill-img_0227-maria-de-bruyn-res   bill-img_0229-maria-de-bruyn-res

re-installing-the-map-img_0189maria-de-bruyn-signed-res

road-repair-img_4866-maria-de-bruyn-res

buckthorn-img_5725-maria-de-bruyn-res

Our volunteer crew is usually a small group of retired persons and a couple students (2-5 people). We’d love to have more people join us so we could get more done and have more input for our conversations covering a range of topics such as botany, geology, wildlife observation, music, sports, travel and current events. The volunteer time of Tuesday mornings unfortunately rules out people who have jobs requiring their presence there on weekdays but we remain hopeful that new volunteers will join us. If you live in the local area and are interested, contact the volunteer coordinator at the NC Botanical Garden!