Tag Archives: coloring

Adorable anoles — lizards with moods!

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Hello, readers — it’s been a while! Time seems to be passing ever faster for me with each new year of life. I was surprised to realize that it’s been a couple months since I posted a blog. So here is a column that I just submitted to a local newspaper with a few more photos than the paper could accommodate.

One of my favorite local reptiles is the Carolina anole (Anolis carolinensis). These cute lizards can be seen year-round since they don’t hibernate. In my experience, however, they seem to be more active — or at least viewable — in late summer and early autumn.

Also known as green anoles, they are the only anoles native to the southeastern United States. Green is nevertheless not their only color. You may encounter dark brown, light brown and green/brown anoles and they might even change their coloring as you watch them.

Unlike chameleons, who change color to blend in with their surroundings so that they can hide more easily from predators, anoles mainly change their skin hues in response to stress or their mood, when they are active or when they want to defend a territory. Darker colors may indicate that they are feeling cold or stressed out.

Sometimes when I’ve watched individuals at length, it’s seemed to me as if they were expressing a variety of moods, even if they didn’t change color.

  

 

Full-grown males are larger than females, but you can also guess their sex based on anatomical features. When males hope to attract a female for mating, they display a brightly colored reddish flap underneath their jaws called a dewlap. When a female sees it, this may induce her to ovulate. Males also show their dewlaps when defending territory against other males.

   

Female anoles can often be distinguished by a row of white markings along their spine, which most males lack.

Like other lizards, anoles regularly shed their skin. Observation last year taught me that they may also eat that skin since this provides them with extra nutrients that may be lacking in their direct environment.

 

Their regular diet is varied, including flies, beetles, spiders, cockroaches, worms, ants, termites, moths and butterflies. Seeds and grains can form part of their meals as well.

    

Carolina anoles are known as arboreal lizards because they spend a lot of time in trees and shrubs. From a higher perch, they can survey their surroundings. Climbing up shrubs and trees can also help them escape from predators who cannot follow them because they lack the sticky foot pads that enable anoles to ascend vertically. Other predators, such as tree snakes and larger lizards, can catch them if they are quick.

 

Sometimes, a predator may catch a green anole by the tail and the anole escapes by dropping its tail—a defensive behavior known as caudal autotomy. A new tail will grow but will be weaker as it contains cartilage instead of bone and often will not be as long.

 

Recently, I learned that birds also hunt anoles when I photographed a blue jay who had caught one. Other birds in our area who go after them include kestrels and bluebirds.

 

The Carolina anoles usually live from about 2 to 8 years. A few who live around my front porch sometimes approach me closely and it’s noticeable that they are watching me, too.

  

Another one decided that an unused bluebird nest box was a good place to hide from predators, obviously not during birds’ nesting season!

It’s been so nice to see the anoles out and about the past weeks. Tonight, we’re having our first freeze of the 2022 autumn/winter season so the anoles may start seeking warm places to hang out. Hopefully, they will have found good places to over-winter.

Readers in the southeast USA who would like information on how to create habitats that can harbor anoles and other native reptiles and amphibians can check out this information site: Reptiles and Amphibians in Your Backyard.

  

My next blog will be the first of a series about Yellowstone National Park. I’d originally planned to post the series this past summer but then couldn’t find some photos I’d taken. The missing card “turned up,” so a photographic tour of the park before it flooded this past June will soon commence.

Have a great day!

The birdy breeding cycle 2020 – 4: growing into adult plumage

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As mentioned in a previous blog, when young birds are ready to leave the nest, they don’t necessarily look like their parents. Many of the altricial birds (ready to move about and forage on their own) may resemble fluffy versions of the adults, as is the case with these hooded merganser ducklings (Lophodytes cucullatus) following their mother.

The brown-headed nuthatch babies (Sitta pusilla) look very much like their parents. Sharp-eyed observers might notice that the tops of their heads are not as brown as those of their parents.

The Eastern meadowlark juveniles (Sturnella magna) resemble their parents but lack the bright yellow and black coloring on the throat and breast.

 

The difference between adult and juvenile downy woodpeckers (Picoides pubescens) is subtle. The female woodpecker has no coloring on the top of her head, which is simply bedecked with the white and black feathers that cover the rest of her body.

The male woodpecker has a red patch on the back of his head.

The immature woodpecker has a red patch on top if the head and this is lost as the bird reaches adulthood.

The Northern mockingbird youngling (Mimus polyglottos) resembles mom and dad quite a bit except for some spotty streaking on the chest.

In other species, the babies start out looking quite different from their parents. Spots characterize many members of the thrush family, with birds like wood thrushes (Hylocichla mustelina) and hermit thrushes (Catharus guttatus) retaining the spots in adulthood.

   

The Eastern bluebirds (Sialia sialis) and American robins (Turdus migratorius), on the other hand, are only strongly speckled as immature birds, losing their spots as they mature.

In some cases, the birds undergo color changes. Male summer tanagers (Piranga rubra) start out yellow-orange with their reddish coloring appearing in patches until they finally achieve their very bright adult red hue. Some of the immature birds are really quite beautiful with their mottled colors.

 

   

The male blue grosbeaks (Passerina caerulea) start out brown and gradually achieve their dark blue feathers with some reddish/brown wing accents.

 

 

Among the birds that undergo a major change are the European starlings (Sturnis vulgaris). The young birds start out with dullish brown or gray hues with some streaking. Eventually, they begin to develop some spotting and then ultimately achieve the beautiful adult summer glossy feathering with green and purple hues mixed in.

 

 

The females of the Eastern towhee species (Pipilo erythrophthalmus) have a brown back above a white breast with reddish sides, while the males have black backs.

The young developing towhees keep you guessing as to their sex since they undergo quite a lot of color changes as they develop. They do have the white in their tails, which helps you identify them as to species.

 

  And then we come to the hawks and owls. It is not unusual for the young raptors to look nothing at all like their parents. The red-shouldered hawks (Buteo lineatus) start out looking like fluffy and then becoming gradually kind of scruffy looking.

     

As they get a little older and leave the nest, they start to resemble their parents more but have more streaking on the breast. As they near adulthood, they look much more like mom and dad.

 

And we end with an example of another raptor. There is a real difference between the baby great horned owl (Bubo virginianus) and its parent as you can see. Many birds are impressed by the adults but ooh and aah over the nestlings. It must be the combination of those big eyes and fluffy feathers that take away attention from the already formidable claws!

               

Next up – a foray into the world of amphibians and reptiles!

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

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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!