Mourning Cloak (Nymphalis antiopa) in Explore the Wild.

Same cloak with partially open wings.

Spring Peeper (Pseudacris crucifer).

This peeper was in Catch the Wind (same frog as above).

Besides the snake being captured by a Red-shouldered Hawk last Friday, Kent (Animal Department) reported seeing what was probably the same hawk catch one in the Lemur Yard on Sunday (1/29/12). From the descriptions given it doesn’t seem as though they were Brown Snakes so, although I can’t be sure, I’m assuming that both were garter snakes. Both Brown Snakes (Storeria dekayi) and Eastern Garter Snakes (Thamnophis sirtalis) have been known to be out and about in both late fall and late winter/early spring. Of course, this is mid-winter. I saw a garter snake along the Eno River, just half a dozen miles or so from the Museum, on New Years Day this year!

A few birds…

A Downy Woodpecker works on gaining entry to a Trumpet Vine seed pod.

A resident Northern Mockingbird hangs out in a holly, one of the trees under the bird's guardianship in Explore the Wild.

Several turtles…

Crawling out on a boulder in the Wetlands, this Yellow-bellied Slider is responding to unseasonably warm weather (12/22/11).

Another yellow-bellied enjoys the sun several weeks later (1/12/12).

And the heat goes on…

This slider catches some late afternoon warmth at the base of a willow (1/24/12).

What looks to be the same turtle as above was out the very next day (1/25/12).

And something left over from summer…

An Eastern Tent Caterpillar egg mass on a small cherry tree along the Dinosaur Trail.

The other side of the egg mass reveals what seems to be an attempt by a bird to get at the eggs within. Or did some of the caterpillars hatch thinking it spring? The black-topped eggs are empty eggs.

It wouldn’t be out of the question for those eggs to have hatched. It is very much like spring on this last week of January. The Red-shouldered Hawks were up performing their aerial courtship displays, I saw a spider wasp carrying a spider along one of the service roads here at the Museum, Spring Peepers have been heard calling (on my drive home Saturday I heard chorus frogs!), the male Belted Kingfisher was in town trying to impress our female with his fish catching prowess (she was having none of it and chased him off), and Jennifer Armstrong (Exhibits) reported seeing a red-shouldered with a snake!

And there’s much more, but you have to be there to see it. So, get out and have a look around!

Perched on a tree inside the bear enclosure, a gray squirrel shows its appreciation for corn-on-the-cob (1/19/12).

I should say that the squirrel in the photo very much appreciates the animal keepers here at the Museum. It was the keepers who tossed the corn into the Black Bear Enclosure. The corn was meant for the bears to eat but the squirrel beat them to the punch.

Happy squirrel.

Great Blue Heron.

Great Egret peering into the water.

The heron in the above photo is actually looking down at me, not a fish, but you get the idea. The heron was in a pine tree above the path in Explore the Wild.

What’s interesting about the photo is that it clearly illustrates the fact that herons have binocular vision and can see objects beyond and below their bills, helpful if you make your living plucking fish out of the water. Among land or air based predators binocular vision is the norm.

While herons’ eyes are placed on the sides of their heads allowing them to see potential trouble heading their way from the side, they are far enough forward that both eyes can be used to peer down into the water at their prey. Two eyes are better than one when trying to gauge position and distance.

Herons are able to detect trouble approaching from the sides as well as watch for prey below.

Birds such as mallards, and mammals like rabbits, have their eyes placed high and laterally dead center on their heads allowing them a 360 degree view of the world. It’s tough to sneak up on either. Although herons can’t see directly behind themselves, a simple turn of that long flexible neck lets them quickly checkout who’s sneaking up from behind. They give up some of their ability to see potential predators approaching from the rear in order to have bino vision, but you still have be be on you tippy toes to sneak up on them.

OK, so a heron can see with binocular vision helping it gauge the distance and location of the object of its attention (fish in water), but how does it deal with refraction? You know, when you put a stick into the water it looks like it’s bent. The light is bent by the different (relative to the air) refractive properties of the water. Unless the fish is on the surface, say it’s 6 inches or so under the water, it isn’t actually where it looks like it is. How does the heron allow for refraction when jabbing at a fish in water?

I’ll leave that one to you.

Red-shouldered Hawk in Explore the Wild.

People who are not familiar with the species often look at me with confused eyes when I tell them that the hawk perched in the trees before them in the swamp here at the Museum is a Red-shouldered Hawk. Why would they name this hawk “red-shouldered,” and where are the red shoulders?

A Red-tailed Hawk has a brick-red tail. That name makes sense. The Red-shouldered Hawk (RSHA) has a reddish belly and chest. Why not name the hawk Red-bellied, or Red-breasted Hawk? Even the Latin name for this hawk doesn’t give a clue as to why it’s named red-shouldered, Buteo lineatus means lined or striped hawk.

RSHAs have a reddish patch of feathers, which comprise most of the secondary upper wing coverts, that stretch from the actual shoulder of the wing to the wrist. The red “shoulder” is not always visible on perched birds.

The red patch is not always obvious when the bird is perched (same bird as above).

It’s a different story when the birds take flight or have their wings stretched out to preen, or when dealing with prey.

The reddish colored upper wing coverts (so-called shoulder) are obvious in flight (photo - 10/09).

This RSHA has just dropped in on a frog in the Wetlands. Note the red wing patches (photo - 4/10).

So, now you know why the Red-shouldered Hawk is called a “Red-shouldered” Hawk. But wait, what are secondary wing coverts?

Coverts are relatively small feathers that overlap and cover the bases of the larger flight feathers on a bird’s wing, the primaries and secondaries. The coverts that cover the bases of the primary feathers are called primary coverts. You can probably guess what the coverts that cover the bases of the secondaries are, that’s right, secondary coverts.

There are coverts on both upper and lower surfaces of the wing to cover both sides of the flight feather bases. The coverts are further divided into groups as the greater primary covers, median primary coverts, lesser primary coverts, marginal primary coverts…there are also coverts that cover the bases of the tail feathers…their purpose is to create a continuous, smooth surface across the wing, or tail, which aids considerably in the act of flying, less drag.

GBH-1 on the far side of the Wetlands.

For the past several years we’ve had a Great Blue Heron (GBH) in the Wetlands on nearly a daily basis. It seems to be the same blue heron, or at least it behaves in the same manner each time that I see it, it’s people shy and stays on the far side of the Wetlands when people are present. Other GBHs come into our Wetlands from time to time, I’ve seen as many as three at a time foraging amongst the willows, but most of them do not exhibit the same wariness as the “local” GBH (we’ll call our heron GBH-1).

For the most part, other than the mergansers and kingfisher who compete with the heron for food, the Wetlands belongs to GBH-1 and he, or she, has it all to itself, especially during the winter months. Lately though we’ve had a Great Egret staying with us and another GBH (GBH-2) has been drawn to our little oasis for the many tadpoles and shiners swimming about in the shallows. The word is out!

The egret jabs at a fish just feet from the boardwalk.

and comes up a winner.

The new arrivals are not quite as reluctant as GBH-1 to take advantage of the abundant shiner population along the edges of the Wetlands during peak visitor hours. You can often see the egret feeding a few feet from shore while GBH-1 sits over on the far side of the Wetlands resting, preening, or just waiting out the crowd of human visitors.

GBH-1 escorts egret from the area (the size difference is exaggerated here, the heron is closer to the camera).

Of late, the competition has apparently become too much for GBH-1 to bear, he’s taken to harrying the intruders at every chance. In the past few weeks I’ve seen GBH-1 repeatedly chase the other heron and egret off into the woods or out beyond my line of sight up and over the pines. They always seem to come back though, or sit it out among the dense branches of the willows or pines or even on the boardwalk railing until GBH-1 is not watching.

It's amazing to watch these large birds maneuver through the trees (wingspan about two meters).

GBH-2 waits for the all-clear before heading down to the water.

Stepping lightly, GBH-2 heads towards the abundant fish in the smartweed just a few short yards away.

Too late, GBH-1 has spotted GBH-2 and is on the way to roust the intruder.

All of these herons know that there is a rich supply of shiners and tadpoles in one little corner of the Wetlands. That supply is dwindling as the fish and tadpoles get eaten by the birds. But while it lasts, is it worth protecting?

GBH-1 spends much time and energy chasing after the two newcomers. But although GBH-2 and the egret spend more time than they’d like fleeing GBH-1, they also sneak quite a bit of time eating while GBH-1 is sitting on a rock, afraid to approach the edge of the Wetlands because of the human traffic going by.

I watched the egret for about fifteen minutes while it stood in the smartweed and saw it catch five fish and a tadpole. Every fish or tadpole that egret eats is potentially one less for GBH-1. GBH-1 relies on this Wetlands for its daily sustenance. It’s a matter of life and death for these birds, all of them. Although we’ve had a very mild winter so far, that could change at any time. Cold weather means more fuel needed to feed the engine that powers these birds. GBH-1 obviously feels that this Wetlands is a resource it will fight for.

Although it’s not fun and games for the herons, I’ve haven’t seen any of the birds make contact, actually strike one another. Too risky, even a minor injury could be fatal in the long run for these birds. A sprained limb, or worse, a broken limb, would almost certainly bring eventual death to a heron. It’s better to chase-and-run than do actual combat.

As I said, it’s not fun and games for the birds, but it’s certainly fun, and interesting, for us humans to watch the birds jostle for position in the Wetlands. I just hope that GBH-1 can maintain the pace. I have a feeling, though, that there will be fewer harrying sallies as the season progresses. I think that GBH-1 will give in to the other birds’ presence. GBH-2 and the egret don’t seem to be taking the hint, and GBH-1 can’t keep it up forever.

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What’s the difference between an egret and a heron? Not much. Along with bitterns, herons and egrets comprise the family Ardeidae. The term egret is generally used to describe the white plumaged members of that family, although the Reddish Egret has both a white and dark form, the dark form having a blue-gray body and reddish neck feathers.

There is also a white form of the Great Blue Heron and the Little Blue Heron is white for the first year of its life, turning blue the following spring after hatching. Confused? Don’t worry, you wouldn’t be totally wrong if you called an egret a heron.

The word egret comes from a French word, aigrette, meaning a fluff or plume of feathers worn as a hair or head ornament, or jewels depicting such. The pretty, long legged, long necked white birds that we now called egrets got their name from the fact that they wear long elegant looking plumes, mostly on their backs, during the breeding season. At one time the birds were harvested for those feathers which were most often used in the millinery trade, the birds were killed and their feathers put on headwear.

I had seen a sharp-shinned earlier in the day as it skillfully maneuvered through the trees behind the Lemur House chasing song birds. Sharp-shinneds eat song birds. The bird that I was looking at perched up by the wolves appeared to be the same bird as I had seen earlier. It missed catching the object of its pursuit through the wolf yard as it had that morning.

Just as quickly as it had arrived, the hawk was gone, off through the woods behind the wolf enclosure.

I noticed the female wolf, the huntress, pawing at something near the bottom of the fence at the top of the ridge. All of the wolf’s attention seemed concentrated on that one spot. Because of the angle, I couldn’t see what she was doing, although it appeared as though she had caught something.

The animal department had placed a few “cardboard sheep” in the enclosure earlier in the day as enrichment for the wolves. The boxes are made to look somewhat like sheep with legs, head, tail, and have sheep’s wool attached to give it some authenticity. The wolves typically tear them apart and you can see pieces of wool throughout the enclosure soon after the “sheep” are placed in the enclosure. Perhaps the wolf was playing with a piece of “cardboard sheep.”

After a few minutes of pawing, female 1287 turned around and I could see what looked like red feathers hanging from her lips. She turned again, this time a male cardinal dangled from her lips. She had captured a cardinal!

When the sharp-shinned hawk came zipping through the trees a few minutes earlier, all of the birds that had been peacefully feeding on the ground and shrubs inside the enclosure scattered. Apparently the cardinal had either slammed into the fence in the panic, or had sought shelter behind a rock up at the top of the wolf enclosure, which turned out to be not a rock, but a wolf, and was quickly pounced upon.

Once again, I did not have my camera with me, this time because it was raining (poor excuse, I know).

However, this little event demonstrates that what may be a tranquil, peaceful, even boring, scene at the time can turn into something very exciting, very quickly.

The link to the camera has changed and is now:

http://www.ustream.tv/channel/jordan-lake-eaglecam

You’ll have to watch a brief ad before you can see the nest, but it doesn’t last long so hang in there for 20-30 seconds and you’ll be able watch the adults incubate. You may even get a glimpse of the adults turn the eggs and readjust the nest a bit (I know, incubation is not very exciting, but it’s an eagle’s nest!).

Enjoy!

This "leaf" is about 2 inches across and appears to have been jabbed onto the end of the twig.

It’s winter and the trees, most of them, don’t have leaves on them. But it was pointed out to me by Meredith (Master Teacher here at the Museum) that several small trees on the south side of the Wetlands still had some of their leaves attached, though they were all attached to the tree in an odd way.

According to Meredith, the leaves looked as though they had been stuck onto the twigs in a manner as would a receipt on a receipt spike, as if they had been pushed onto the end of the twig. The little leaves were not actually attached to the tree but would spin freely and ride up and down on the twig with the wind.

Hmm, another mystery to solve.

The bark of a young sycamore.

First, if possible, we had to determine what kind of tree we were dealing with. There were three or four of the trees next to the boardwalk where it descends into Explore the Wild.

They were all sycamores, young sycamores (12′ – 20′) that had yet to acquire the pealing lower bark and white upper bark of mature trees. I remembered the trees from earlier in the year when they had their large, broad leaves. But there were more clues to the identity of the trees besides the remembrance of the past season’s leaves.

The large bud and leaf scar, which surrounds the bud, are distinctive.

Leaf scars are what’s left after the leaves fall off of the tree, they are where the leaf petiole, or leaf stem, had been attached to the twig. Sycamore leaf scars are distinctive, although I had to be reminded of that by referencing a tree field guide. The scars nearly encircle the buds.

OK, so it’s a sycamore, but what are those little leaves spinning around on the twigs? I remember seeing those small “leaves” when they were green during the growing season. I was curious as to why they were so small. They looked like stunted sycamore leaves. But I simply shrugged them off as, well, stunted sycamore leaves that hadn’t grown out completely due to some insect or disease infestation. And besides, I’m sure that at the time I was too busy doing something else to dig any deeper, there’s so much going on during the summer, you have to pick your mysteries carefully.

Both leaf and stipule scars are clearly seen here.

A stipule is an outgrowth of a young leaf and is part of the base of the leaf. Although some plants do not have stipules, in those that do the stipule can take on many forms. It can be a very small tendril like structure, a spine (the thorns on acacia trees are stipules), or it may take on the shape and form of a leaf.

I have yet to discover the definitive answer as to the purpose of stipules but they may have evolved as a protective structure for young emerging leaves. The stipules that are more leaf-like in structure may actually perform some of the functions of leaves (photosynthesis).

Sycamores happen to have stipules that are very much like leaves.

The stipules remain on the tree much longer than do the leaves due to their shape.

Why don’t the stipules fall off the tree when the leaves do. Many of them do, but those that don’t are still on the tree during winter due to their manner of growth. As you can see in these photos the base of the stipule nearly surrounds the twig, it’s attached to the twig for most of the twig’s circumference.

The leafy part of a sycamore stipule grows both outward and around the stem. The stipule that I have in my hand at the moment had actually grown into itself, the sides had grown together and were attached, holding it onto the twig.

When the stipules dry out they retain their shape (like leaves do) and since they grow around the twig, and despite the fact that they have detached from the twig at the point of growth, they stay on the twig. Eventually they become too brittle or decay to a point where they break apart and fall to the ground. But for most of the fall and part of the winter some of the stipules remain on the tree if for no other reason than to make curious naturalists wonder what they are and why they are there.

Read enough about stipules? If so, you can stop here, I’m done. If not, you can look deeper into their structure, origin, and purpose by browsing through “The Nature and Origin of Stipules,” Ansel Augustus Tyler, at Google books where that publication has been digitized and is viewable online.

The first ice of the season on the Wetlands.

The ice will soon be history, all gone. I, or we, know that the ice will be gone within a day or two since the TV, internet, and radio tells us these things ahead of time. But for some of the creatures that live in and depend on the Wetlands for food, ice is not a good thing and it can’t be predicted when it will go away. The kingfisher who needs to dive into water to catch fish, the heron, egret, mergansers, and others don’t know when the ice will melt. Should they move on, or wait it out?

The birds can afford to hang out for a few days to see what will happen, after all, they have wings and can move to bigger water if things don’t improve. They can be at Falls Lake in minutes and there are many other local ponds that are a bit deeper than our Wetlands and which may not freeze as quickly.

A frozen shiner.

The photos that you see here were taken on January 4th and show some of the birds who decided to stick it out long enough to see if the water would open up for them.

But first, some of the shiners which have been huddled up in a shallow corner of the Wetlands for nearly a month now did not fare well. However, most of them, the ones not yet eaten by the birds that you see in the photos, are still splashing around in the water and have actually kept a small bit of water open because of their thrashing about.

The Great Egret (below) is probably the same bird seen in the Wetlands on the 22nd of December (it was also seen on the 24th).

The new addition to the Wetlands, a Great Egret, rests while the ice melts.

This egret is more people tolerant than its larger relative, the Great Blue Heron, and allows for a closer approach.

A closer look at our new friend.

Kingfisher and GBH decide to stay and see what happens.

The hawk looks over its shoulder at some, unheard by me, noise coming from behind.

One of the local Red-shouldered Hawks has resumed its hunting strategy of sitting quietly in the willows watching for the slightest movement to pounce on any unsuspecting frog, tadpole, shrew, or rat.

Despite the cold, it was a good day to be outside.

By the way, it may reach sixty degrees by the end of the week! Are you going to be sitting inside reading blogs about nature, or outside experiencing some of the things those blogs speak about?