Always be on the Lookout for the Presence of Wonder
~E.B. White
I saw my first one yesterday. I glanced out the window and a streak went by the flowers I had just bought for the window box. I went to the door and I saw it hovering, checking out the red taillight on my car, then it zipped away. I went out to the garden and I heard the unmistakable hum of its wings as it checked out the feeder I had put up last week in anticipation of its return.
Male Ruby-throated Hummingbird
The male’s are first to arrive, to find a territory, to feed and defend. It won’t be long now before a half dozen or more are buzzing over the garden, zipping by my head, squabbling with each other at the Coral Honeysuckle blooms. Even though there are still Juncos at the feeding stations, the signs are irrefutable – the Eastern Bluebirds are on eggs, the Redbud is blooming, and the first hummingbird is back….spring is here.
…I hear the dream frog at a distance…My dream frog turns out to be a toad.
~Henry David Thoreau
In a post in late February I discussed the vocalizations of a variety of frogs and toads I have photographed in North Carolina. Last week I had the opportunity to spend some time with one of my favorite spring-time songsters, the American Toad. All I had with me was my iPhone, so the image quality is a bit limited, but it was an amazing sight. It was in a seemingly unlikely place, a rocky Piedmont stream. I usually find these toads along sandy or muddy shores of pools, ponds, lakes, or even water-filled tire ruts in a field, but here they were trilling along what could almost pass for a mountain stream. As I mentioned in the other post, the far-off trill of American Toads reminds me of some alien spaceship sounds in a cheap sci-fi thriller. To Thoreau, they were his dream frogs.
American Toad calling
He described it as a trembling note, some higher, some lower, along the edge of the earth, an all-pervading sound. Nearer, it is a blubbering or rather bubbling sound, such as children, who stand nearer to nature, can and do often make. Indeed, the call is easily imitated by one of two methods – the lip flap, or the tongue flutter (some people are apparently capable of only one of these methods). Go ahead, practice it – probably best done when no one else is around….purse your lips and blow air out of them while making a high-pitched humming sound (the lip flap); or let out a high-pitched hum while vibrating the tip of your tongue on the roof of your mouth (the tongue flutter). Now, doesn’t that feel good? Let’s see how you compare to the real thing…
Thoreau is correct in saying that the closer you are to the calling toad, the less dream-like the quality, but it is still an amazing sound. His comments on the visual aspect of a group of toads that were froggily lusting are also worth noting…
After an interval of silence, one appeared to be gulping the wind into his belly, inflating himself so that we was considerably expanded; then he discharged it all into his throat while his body or belly collapsed suddenly, expanding his throat to a remarkable size. It was a ludicrous sight, with their so serious prominent eyes peering over it; and a deafening sound, when several were frogging at once, as I was leaning over them.
Deafening indeed. And last week it came in waves. First one, then another of the suitors would trill, often with four or five all at once. And all of this sound was for the sake of one large female toad in a stream side pool. But she was already preoccupied with one of the lucky fellows in a behavior known as amplexus (Latin for “embrace”).
In amplexus, a male toad grabs the larger female under her armpits with his front legs and holds on. As the female deposits eggs, the male releases sperm into the water and fertilizes them. I have seen anuran amplexus many times, but had never witnessed the actual egg-laying until last week.
As I tried to get some video of calling males, the coupled pair maneuvered over to a quiet pool and began to deposit eggs. The female crawled into slightly deeper water, submerging the pair. The male moved his hind feet and it appears as though he was catching the eggs as they were being released, presumably to ensure fertilization.
This went on for several minutes until he finally moved his feet onto her back and she started crawling around leaving a string of eggs behind. At that point, I turned my attention to the bevy of trilling toads still trying for a chance. At times like these, male toads will often skirmish with one another or mistakenly grab anything that moves. One of my all-time favorite museum workshop quotes occurred one night while leading an amphibian program. We were watching a group of American Toads as they were froggily lusting and my co-lead, Alvin, showed us all something that only esteemed herpetologists know. As a male toad was swimming toward us, Alvin told the group that these guys will often grab onto anything that moves during these breeding bouts. As he spoke, he placed two fingers in the water and wriggled them, making a ripple that the toad immediately picked up on. The toad swam quickly toward the moving fingers and clasped them in its best amplexus move. Alvin pulled it gently out of the water, the toad still hanging on. One teacher exclaimed, “Oh My God, he’s a frog whisperer”…a high honor indeed. When the grabbee is another male toad, instead of a pair of herpetologist fingers, something else happens.
Male American Toads give something called a release call when they are grabbed in an amplexus-style manner (in the armpits). The short clip above ends with one male grabbing another, followed by a quick chirping release call.
Strands of American Toad eggsA mass of American Toad eggs in a stream side pool
The result of this frenzy of activity is, of course, a new generation of toads. Females lay a double strand of eggs that may be several feet long (she may lay several thousand eggs each season). Tiny black tadpoles hatch within a week or so. While this rocky stream breeding habitat may have an advantage over certain shallow pools that might dry up in hot weather, I bet there is a high probability that the eggs or tadpoles can be washed downstream in heavy rains. But something must be working as there certainly were a sufficient number of toads attending the breeding session that night.
I laid on the rocks and watched and listened to the toads for over an hour. It was a mesmerizing scene and one that they did not seem to mind sharing with an observer. I’ll leave you with more of Thoreau’s observations on his dream frogs…
You would hardly believe that toads could be so excited and active. It is a sound as crowded with protuberant bubbles as the rind of an orange. A clear ringing note with a bubbling trill. It takes complete possession of you, for you vibrate to it, and can hear nothing else.
The toads completely fill the air with their dreamy snore; so that I wonder that everybody does not remark upon it and, the first time they hear it, do not rush to the riverside and the pools…
I shared an early sign of spring about a month ago when I posted some images of Spotted Salamander spermatophores (Salamander Candy) in a woodland pool near my home. Last week I checked out that pool, and a few others, looking for the next step in the recipe for creating a full-baked Spotted Salamander – the egg masses.
Recently deposited egg mass of a Spotted Salamander (click photos to enlarge)
These jelly-like blobs usually contain 50 to 200+ individual eggs. When first deposited, they are about the size of a golf ball. Over the next few days, the gelatinous mass absorbs water and grows much larger, often almost attaining the size of a somewhat elongate softball.
Early development of embryos from shady woodland pool
Most of the egg masses I saw in the shady woodland pool were still in the “nub” stage – the developing embryos are not yet recognizable as salamander larvae.
Macro shot of egg mass using twin flash
The amount of detail you see depends greatly on the light used to illuminate the egg mass. It will probably take another week or two of warm weather before these hatch.
Roadside ditch containing salamander larvae and eggs
That same day, I traveled to an open roadside site near Jordan Lake where I found salamander eggs in the past during my amphibian workshops for the museum. The site has been altered since I last visited and is smaller now due to some bulldozing nearby.
Egg mass from roadside ditch
To my delight, there are still salamanders hanging on at this site.
These are much further along in their development. They may have been deposited at an earlier date than those from the other location, but since this site receives full sun most of the day, these eggs probably develop faster than those from the shady woodland pool.
Egg mass using flash
Again, the angle and type of lighting gives a much different look to the art of the egg mass.
Here are a few close ups of the developing larvae…
The embryo lengthens after the “bud” stageAt this stage they remind me of tiny whales or manatees encased in glass bubblesYou can see a larval form now including the “balancer” under the chin – one of two fleshy appendages the larva has for a few days after hatching that help it maintain position in the water columnThe last stage before hatching. Note the two layers to the egg (all of which is also embedded in a gelatinous matrix with the other eggs). You can also see the symbiotic green algae in the egg layer.
The gelatinous matrix begins to deteriorate right before the larvae start hatching so you get these individual, greenish salamander globes in the water. I think this may be my favorite part of the recipe.
…and there where the pale April sunlight filters through the leafless branches, nod myriads of these lilies, each one guarded by a pair of mottled, erect, sentinel-like leaves.
~ Mrs. William Starr Dana in How to Know the Wild Flowers, 1917
Few spring woodland flowers put on a show like Erythronium americanum (although I am wondering if it is now called E. umbilicatum according to recent botanical references). The yellow flowers and mottled leaves often form expansive carpets in the leaf litter of rich woodlands in the Piedmont and Mountains.
Trout Lilies are one of our more striking spring woodland wildflowers (click photos to enlarge)
Most of us know it by a variety of other names, most commonly Trout Lily. But others have called it a variety of names including Fawn Lily, Yellow Adder’s Tongue, and Dog Tooth Violet. When I first started my career as a naturalist with state parks, I found myself racing to learn as much about the plants and animals of North Carolina as possible so I could train rangers and develop programs for the public. I was weak in plants, especially wild flowers, and I found myself trying to find interesting information to share with people about the plants once I identified them. One reference I stumbled upon was How to Know the Wild Flowers, A Guide to the Names Haunts and Habits of our Common Wild Flowers by Mrs. William Starr Dana (online at https://archive.org/stream/howtoknowwildflo00staruoft#page/n9/mode/2up).
This yellow flower is known by many names
Her insights into plant names and uses provided some welcome tidbits to pass along in programs and helped me to better appreciate the abundant wild flowers of our state. Here is what she said about the many common names of Erythronium (which she listed as Yellow Adder’s Tongue and Dog’s Tooth Violet)…
The two English names of this plant are unsatisfactory and inappropriate. If the marking of its leaves resembles the skin of an adder why name it after its tongue? And there is equally little reason for calling a lily a violet. Mr. Burroughs (John Burroughs, a famous naturalist and writer) has suggested two pretty and significant names. Fawn Lily, he thinks, would be appropriate, because a fawn is also mottled, and because the two leaves stand up with the alert, startled look of a fawn’s ears. The speckled foliage and perhaps its flowering season are indicated in the title, trout lily, which has a spring-like flavor not without charm.
Looking down on a Trout Lily flower with the mottled leaves of several plants in the backgroundFrom above, you can see the sepals have much more maroon color on top than do the petals
The flowers have three petals which are yellow on both sides (with a band of purple along the top midrib) and three sepals (that are yellow underneath and purplish-maroon on top). Together, when of a similar shape and color, they are often called tepals.
Flowers close each evening
They join at the base forming a somewhat tubular structure when closed. Flowers close each night and usually open by mid-morning on sunny days, but may remain partially closed on particularly cloudy or rainy days.
The petals and sepals curve upward when the flower opens
When they do open, it can be a remarkable change, from a purplish-maroon drooping tube to a dancing yellow flower, almost as if a strong puff of air has blown up from underneath. Now the tepals all reflex upward and inward, exposing the reddish stamens below.
Flowering Trout Lily plants have two leaves
A Trout Lily that flowers always has two leaves. Since only a small portion of each colony of plants produces a flower in any given season, the vast majority of plants only produce one leaf. The extra leaf may be for the added energy required to produce a flower and seed.
Trout Lilies often occur in dense colonies
Colonies of this beautiful flowering plant form more by vegetative reproduction than sexual means. Plants have deep corms which are bulb-like underground stems that store food. These corms produce additional corms which helps create colonies of cloned plants which can be decades old. One reference said the mottled pattern in cloned plants is similar, so you can look at the leaves of a large patch of the plants and determine how many colonies are present, and how far each colony has spread. These dense colonies also help stabilize the soil with their network of underground connections. In addition, it has been shown that the leaves accumulate phosphorus from rain water and runoff at a level higher than most plants. This critical nutrient is then returned to the forest soil in a form more available to plants when the Trout Lily leaves decay.
The abundant, early-blooming flowers also serve as an important source of pollen for queen bumblebees when they emerge and begin construction of their nests. So, this plant of multiple names also has multiple benefits for the forest and for the woods-watchers who enjoy its brief appearance each spring. The naturalist, John Burroughs, described a feeling many of us have had when he wrote…
In my spring rambles I have sometimes come upon a solitary specimen of this yellow lily growing beside a mossy stone where the sunshine fell full upon it, and have thought it one of the most beautiful of our wild flowers.
Surely no flower of the year can vie with this in spotless beauty. Its very transitoriness enhances its charm.
~ Mrs. William Starr Dana in How to Know the Wild Flowers, 1917
Bloodroot flowers are beautiful, yet brief (click photos to enlarge)
Twice this past week I came across one of my favorite wildflowers, Bloodroot, Sanguinaria canadensis. When open, the pure white flowers of Bloodroot are large and easily seen compared to the tiny blossoms of many of the other woodland spring wildflowers. But look fast, as each flower typically only lasts a couple of days before a slight breeze, rain, or other environmental disturbance causes the petals to drop. The flowers produce no nectar so any pollinators are either fooled by the showy blossoms or come to gather the pollen. As with several other early spring bloomers, Bloodroot can self-pollinate. This beautiful specimen was one of three seen at a short hike at Johnston Mill Nature Preserve in Orange County, one of several properties managed by the Triangle Land Conservancy.
Bloodroot bud extending beyond its protective leaf
This otherwise delicate flower is named for the blood-red juice that escapes if you pick a leaf or cut into the rhizome. Native Americans used it as a dye and body paint and it is used now in some toothpaste brands to reduce plaque growth and fight decay. On the hike last week at Pilot Mountain State Park, we found a solitary Bloodroot growing on a steep bank above a stream. It was a single bud, seemingly protected by a curled leaf wrapped around the stem.
Bloodroot leaf back lit by the setting sun
After the flower blooms, the leaf expands and often becomes horizontal. A couple of years ago, I came across a single leaf on a steep slope at Swift Creek Bluffs Nature Preserve, another Triangle Land Conservancy property. It glowed in the low angle light, highlighting the textured network of veins in the odd-shaped leaf. It was one of those moments when you simply are in awe of a small bit of nature. Even though their brief show is quickly passing in this part of the state, I hope to see more Bloodroot on upcoming trips to the mountains, as spring progresses up the slopes. Each encounter is time-well spent with a ephemeral woodland beauty.
Yadkin River at Pilot Mountain State Park (click photos to enlarge)
There is, indeed, something magical about a river. It is the lifeblood of the land. It carries your mind to places yet undiscovered and brings surprises to your doorstep. It is a gentle, reassuring friend in its constant murmurings, or a raging threat to be respected and sometimes feared. And, like any body of water, it is a haven for hidden life. On a hike along the Yadkin River this past weekend, I came upon signs of abundant life that had left the river to risk exposure in the world above.
Stonefly exuviae on tree trunk along the Yadkin River
The tree trunks and rocks along the river were adorned by hundreds of stonefly exuviae. Such a strange word, exuviae, almost otherworldly, as were the dried, lifeless forms on the river bank. Exuviae is derived from the Latin, exuere, meaning to remove. It is defined as the cast off skins or other coverings of animals. This shed skin shows the typical immature stonefly body plan – a somewhat flattened shape to enable it to better cope with the currents, stout legs with two claws at the tip, and two tails (cerci).
Stonefly exuviae piled on top of one another
The exuviae were thick on some tree trunks and even piled on top of one another in a few places, as if there had been a mad dash to escape the rushing river. I am not sure which species this is, but they all looked alike, so I imagine there had been a mass emergence of the aquatic immatures of a single species over a short period of time. This is typical behavior for stoneflies and mayflies as they emerge to transform to the adult form and mate. Fly fishermen are well aware of the so-called “hatches” of various species of aquatic insects and have developed an entire artistic culture around mimicking the colors and patterns of each species with artificial “flies” designed to entice hungry fish to strike.
Immature stoneflies are called naiads (you will hear some refer to them as nymphs) and live in well-oxygenated waters (streams and rivers and some lake shores) for one or more years depending on the species. This one was a large species, the exuviae being over an inch in length. Many of the larger species are carnivorous, preying on other macroinvertebrates living in the river.
A pair of stonefly naiads showing the slits on their “backs” where the adults emerged
Like other arthropods, the naiads of stoneflies must periodically shed their exoskeleton so they can grow. This may happen from 12 to 24 times depending on the species. When the time is right, the last stage of the naiad crawls out of the water and clings firmly to a surface and begins its final transformation. A longitudinal slit forms along the top of the thorax and a winged adult crawls out, leaving the “skeleton” behind. Since I do not live near suitable habitat, I rarely see the short-lived adults, but have found many exuviae over the years as I walk along the edges of streams and rivers.
Stonefly naiad showing linings of trachea in cast skin
The sheds contain an amazing amount of detail such that I could probably identify the maker to species with the right field guide. Noticeably visible against the dry, gray skin are some white filaments near the head. These are the linings of the trachea, part of the respiratory system of the insect, which are also shed during each molt. Many species of our stoneflies emerge in late winter and early spring and the number and amazing detail of all the exuviae indicated that this had been a recent event. If only I could have witnessed it. But seeing the result is also amazing, as the evidence may only last a few days or weeks depending on the weather. And the abundance of exuviae is a good sign that this stretch of the Yadkin is in pretty good shape, as stoneflies are generally indicators of good water quality. Sadly, far too many of our waterways are being threatened by excess sediment, toxic pollutants, or other human-caused factors. All of us need to spend more time with our rivers, get to know them, and appreciate the life-giving qualities they possess. Perhaps then we will care enough to learn how we can better protect them.
The flowers of late winter and early spring occupy places in our hearts well out of proportion to their size.
~Gertrude S. Wister
Spring is a wonderful season for so many reasons, not the least of which is the explosion of wildflowers that spreads across our state beginning in February and lasting through May. One of the earliest of these beauties is Hepatica.
Hepatica flower just starting to open a couple of weeks ago here in the woods in Chatham County (click on photos to enlarge)
I saw my first Hepatica flower here in the woods near the house on March 11.
A patch of Round-lobed Hepatica at Pilot Mountain State Park
On my trip to Pilot Mountain State Park this past weekend, there were many patches of Hepatica just begining to bloom on steep slopes near the oxbow pool and along a small stream we explored. Spotting them peeking out of the leaf litter is one of the simple joys of a walk in the woods this time of year. The small flowers are easily overlooked if you walk too quickly, but once seen, they demand that you get down on the ground for a closer look. Combine that with the amphibian eggs and larvae we saw, and you have the perfect start to the season.
Hepatica leaf from last year. Older leaves have splotches of purple on them and are reddish-purple underneath.
The word hepatica comes from the Greek word hepar, meaning liver. The three lobes and the purplish color of older leaves do somewhat resemble a liver and this plant was once used to treat liver ailments. Herbalists once believed in the so-called Doctrine of Signatures, in which plants that had any resemblance to human body parts were thought to be useful in the treatment of ailments of that part of the human body.
Hepatica leaves are evergreen with the ones you see early this spring being last year’s leaves. They no doubt are able to photosynthesize on warm winter days and then go full tilt in early spring before many other woodland ephemerals are even out. This may give them a head start on many of the other spring wildflowers. The old leaves die back and new ones emerge following the flowering.
The small, delicate flowers of Hepatica are usually lavender to blue in color although I have found some that are pinkish or almost all white. They vary in number from 6 (the most common number) to 8 or more. And it turns out they are not what they appear to be – what look like petals are technically the sepals – Hepatica has no true petals. And the three fuzzy things beneath the flower that look like sepals are actually bracts, or specially modified leaves. But it really doesn’t matter to a pollinator or a woods-walker looking for signs of spring.
Hepatica flowers can vary in color and the number of petal-like sepals
Spring comes earliest to the bottoms of stagnant pools – there no cool winds blow – no hoar frosts penetrate – but they grow protected as under a glass. There are fewer disturbing influences to rob them of the full advantage of the sun’s increased altitude.
~Henry David Thoreau
Conservation groups, in partnership with Partners in Amphibian and Reptile Conservation, are designating 2014 as the Year of the Salamander (http://www.parcplace.org/news-a-events/2014-year-of-the-salamander.html). So, naturally, one of my naturalist friends has decided this is the year to see as many of North Carolina’s salamanders as possible. With that in mind, a few of us went to Pilot Mountain State Park this weekend in search of whatever amphibians we could find.
Big Pinnacle at Pilot Mountain State Park (click photos to enlarge)
While many visitors simply drive to the summit and gaze out across the valley, or enjoy the view of Big Pinnacle, we were looking for things in the low country, in the Yadkin River section of the park. I had been to this section only once, years ago, when working for the state park system as a naturalist, so it was a great chance to do some exploring.
Oxbow pool along Horne Creek
Walking along Horne Creek we came upon an oxbow that is now an isolated woodland pool, perfect for amphibians. An Upland Chorus Frog slowly called but soon fell silent as we approached…a good sign.
Pool reflection
These woodland pools, especially those devoid of fish, are incredible habitats for a wide variety of organisms from macro-invertebrates to frogs and salamanders, They are also beautiful woodland mirrors that reveal a multidimensional world as I stare into the surface, at first seeing only the trees above, and then the dark bottom, covered in leaves. As I walked along the pool edge, I could see a few Water Striders, but little else, until I got to an area where a cluster of sticks protruded from the pool’s surface – amphibian egg masses! At first glance I thought they were Spotted Salamander egg masses, but my friend, Megan, pointed out they were Wood Frog eggs.
Wood Frog egg mass
Compared to the egg masses of Spotted Salamanders, the Wood Frog egg masses tend to be more globular, somewhat larger, and lack the stiff outer gelatinous matrix of the salamander eggs. There were several blobs of eggs attached to the twigs, with some appearing recently laid, and others more developed. As they age, the eggs are colonized by a symbiotic algae, Oophila amblystomatis, which imparts a greenish color to the cluster. This same algae colonizes Spotted Salamander eggs and is believed to utilize some of the waste from the developing eggs while providing some oxygen for them.
Wood Frog egg mass colonized by algae
The Wood Frog egg masses also tend to flatten out at the surface of the pool as they age. While staring at one I noticed some movement – there were Marbled Salamander larvae resting on them. Marbled Salamanders lay their eggs in the fall as these pools fill with rainwater, and their larvae are well-developed predators by the time many of the other amphibian species start to hatch. Looking down I saw one of these tiny pool tigers swim up to an egg mass and position itself, just in case there was an early hatching by a tasty Wood Frog tadpole. The more mature green egg masses had many more Marbled Salamander larvae in attendance (look for the dark elongate shapes in the photo above).
Marbled Salamander larva on Wood Frog egg mass
Since the Wood Frog tadpoles tend to cling to their egg mass for a few days after hatching (to feed on the algae), it is a perfect place for the Marbled larvae to hang out. The hatching frog tadpoles are weak swimmers and easy prey.
Wood Frog tadpole at hatching
I gently scooped up one recent hatchling for a quick photo. Luckily for the frogs, each egg mass contains a few hundred eggs, which should be enough to ensure survival of at least some of the tadpoles.
Woodland ephemeral pools are critical habitats
I love spending time near these pools, waiting, watching, listening – there is so much life to be found. Yet these are often some of the first habitats destroyed when we alter the landscape. I have witnessed once thriving amphibians pools destroyed by nearby earth moving which forever alters the drainage pattern or by intentional draining due to concerns about mosquitoes. In fact, the thriving community of predators in a typical woodland ephemeral pool usually means few or no mosquito larvae can survive. And without the woodland mirrors, both our forests and our natural heritage are diminished.
I encourage you to get out in the next few weeks and sit by the edge of a woodland pool and marvel at the life it contains. But, beware, anyone seeing you at such a pool may start to wonder, as did a neighbor of Thoreau’s back in 1858…
I learn that one farmer, seeing me standing a long time still in the midst of a pool (I was watching for frogs), said that it was his father, who had been drinking some of Pat Haggerty’s rum, and had lost his way home. So, setting out to lead him home, he discovered that it was I.
While out working in the yard yesterday I saw one of the early signs of a woodland spring, the first Falcate Orangetip butterfly. These dainty white butterflies flit through the woods for only a few weeks each year searching for mates and plants in the mustard family on which to lay their eggs. But it was almost two weeks ago I saw my first butterfly of the season. A Mourning Cloak danced silently through the naked trees and landed on a maple to feed on sap. It was late in the afternoon, one day after a brief snow. The birds were still crowding at the feeders, leaving thoughts of a new nesting season behind after yet another cold spell. And yet, here was a butterfly, probably one that had spent the winter huddling in darkness under some loose tree bark or even under a fallen log. Two days later, I added two more species to the early spring butterfly count – an Eastern Comma and a Question Mark. Both of these species, like the Mourning Cloak, are among the few that spend the winters here in NC as adults. They are often seen darting through the woods on warm days in late winter, searching for sustenance amongst the bare trees. This winter has been a cold one and the inaugural butterflies have been slow to awaken. But now, their silent wings are beating, carrying the warm days of spring a little closer.
Hold fast to dreams, for if dreams die, life is a broken winged bird that cannot fly.
~Langston Hughes
Several times this winter I have heard that familiar thud that means a winged beauty has collided with my window. A quick glance shows the track left behind by such a collision – a few feathers stuck on the glass.
Feathers on window pane (click photos to enlarge)
Luckily, at my windows, it is rarely anything more than an interruption in the bird’s burst of flight. But, nationwide, that is certainly not always the case. I was stunned when I saw a recent report providing evidence of the extent of bird mortality due to window kills. In a recent paper published in the journal The Condor, researchers estimated that between 365 and 988 million birds die from crashing into windows in the United States each year. While that is a large range, the point is that significant numbers of birds die each year by crashing into our structures, putting window collisions behind only cats as the largest source of human-related threats that kill birds. One interesting finding is that roughly 56% of mortality occurs on buildings that are 4 stories or less in height; 44% at residences, and less than1% at high-rise skyscrapers. The full report is at http://www.bioone.org/doi/abs/10.1650/CONDOR-13-09. It would be interesting to see if homes surrounded by trees have a higher incidence of bird collisions than those in open areas. Looking at a window from the outside, it is easy to see how a bird in flight, particularly one that has been startled at a feeder by a potential predator, could easily mistake the reflection in a window for safe passage through some branches.
Reflection of trees in my window
I always check to see if a bird has been stunned by a collision, and this week I did find one. So, I went outside to see if I could help. Years ago, my good friend, Paris Trail, shared a rehabilitation method he had used successfully on many birds that hit his woodland windows over the years. If the bird is alive (open eyes are a good sign of this), gently pick it up and bring it inside. It turns out that loss of body heat is a big killer of window-stunned birds, especially in cold weather. The American Goldfinch that hit my window was only slightly stunned, so I skipped one treatment I usually give to such birds – I turn on the faucet so just a trickle of water is coming out. Then I place the birds beak in the trickle for a quick sip (or splash).
This bird was stunned after hitting my window
I then place the bird in a grocery bag and roll the top so it can’t escape.
Paper bag with stunned bird in it
The bag then goes in a quiet, preferably dark, place like a closet for several minutes. This helps the bird calm down a bit and rest. After 15 minutes or so, or until I hear the bird moving around in the bag, I pick up the bag and take it outside (you don’t want the bird escaping into your house). I open the bag, point it out toward the woods, and the bird usually flies out. I have found this method to be very successful in helping stunned birds survive their encounter with a deceptively solid piece of woodland scenery. For some tips on how you can make your windows more bird-safe, see http://www.humanesociety.org/animals/resources/tips/bird_safe_windows.html.
Roads End Naturalist 