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Yellowstone National Park: Part 5. Grizzlies, coyotes and pronghorns – oh my!

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Note: this long posting is likely nicer to see on a laptop than a phone!

During my first spring visit to Yellowstone National Park in 2016, we encountered black bears (Ursus americanus) throughout the national reserve. When a mother bear with her little cubs was spotted, park visitors stopped often to watch the playful young, especially when they were practicing tree climbing.

During my 2022 visit, we did not see black bears but had the good fortune to see quite a few grizzly bears (Ursus arctos horribilis). Some were quite light in color, while others had dark fur. A mama grizzly and her cub were the first mammals we saw (due to my friend Joan’s sharp eyes!) and we must have seen at least one or two every day. (If not a live bear, there were plenty of them featured in artwork in Gardiner.)

Rangers were often present at our sightings or arrived shortly after we did. They mostly warned humans to keep considerable distance from the bears, but we also saw them shooing the bears away from roads when many people were passing by.

(The bears below were shooed back up the hill; the white spots on the photo are snowflakes.)

The “hump” on the grizzlies’ shoulders helped us identify them since black bears lack this feature. Also, when walking on all fours, the grizzly’s rump is lower than its shoulders. The impressive grizzly claws are also much longer than those of black bears.

Sometimes we spotted the grizzlies grazing far away in fields. A few times, we had the good fortune to spot a mother bear with her young cubs.

One mother in particular gave us wonderful views as she wandered about with her triplets. That was lucky for us as grizzlies have one of the lowest reproductive rates of North American terrestrial mammals.

They are not sexually mature before the age of 5 years. After mating in the summer, implantation of the embryo is delayed until the female hibernates. She could miscarry if she does not ingest sufficient calories and nutrients during the summer. She also will not mate again until her cubs have reached three years of age.

One of the most interesting foods that the grizzly bears eat is the adult form of the army cutworm, called the miller moth (Euxoa auxiliaris). This moth has the highest known percentage of body fat of any animal, comprising up to 72% of its body weight! The moths fly from low-lying farmlands to crevices in mountain slide rocks, where the bears go in late summer to dig them out. It’s estimated that a grizzly can eat up to 40,000 moths in a day, thereby ingesting up to 20,000 calories.

One of the grizzlies’ competitors for food, particularly carcasses, are the coyotes (Canis latrans). These beautiful canids are unfortunately detested by many people, as related by Dan Flores in his informative book Coyote America: A Natural and Supernatural History.

At one point, we saw numerous cars parked along a road and stopped to see what everyone was observing. There was a coyote feeding on a large carcass that had already been partly consumed.

The coyote was engrossed in getting some meat off the bone, which was apparently not an easy task. These canids usually eat deer and smaller prey such as little mammals (rabbits, hares, rodents), birds, reptiles and amphibians, and invertebrates. It was not entirely clear to me what this prey had been.

A fascinating coyote behavior is that they sometimes collaborate with badgers to dig up rodents. They even appear to like these fierce predators as people have seen coyotes licking a badger’s face or laying their heads on the badger’s body. A decorated jar found in Mexico dating back to the years 1250-13oo showed this relationship.

Unfortunately, although the coyote figures prominently in Native American/Indian folklore, the US government has initiated and supported efforts to eradicate the species altogether. From 1947 to 1956, about 6.5 million coyotes were killed in the American West. However, these intelligent animals have managed to survive and eventually spread to the eastern United States (where they are now again unfortunately detested by considerable numbers of people).

In Yellowstone, the larger ungulates on which the predators such as bears, coyotes and wolves feed include elk and moose. As mentioned in a prior blog, elk (Cervus canadensis) can be seen up close in Gardiner, the town at Yellowstone’s northern entrance, where they wander through the streets and rest in people’s yards. A more melodious name for them is wapiti, used by the Shawnee and Cree peoples. It refers to the animal’s white rump.

To me, the elk appeared quite large but they “only” measure about 4-5 feet in height. The males’ antlers can grow up another 4 feet, however, giving them a much taller appearance.

The males also have another interesting characteristic — their bugling, which is used to attract mates and mark their territories. This sound is the loudest call of any members of the deer family. The males produce it by roaring and whistling simultaneously!

Because elk prefer colder weather, they are more visible to Yellowstone visitors in the late autumn, winter and early spring. We saw females and young elk in town and spotted the males out in the valleys. They are very social animals and one of the largest herds (about 11,000 members in 2022) is known as the “Jackson Elk Herd”, which migrates between southern Yellowstone and the National Elk Refuge in Wyoming.

The other large, hoofed animal which we glimpsed one day was a moose (Alces alces). This ungulate is the largest member of the deer family, reaching a height of 6 feet (1.8 m) and a weight of up to 1,000 lb (450 kg).

We saw a male — identifiable by the antlers which were just beginning to grow — as he grazed in a marshy area beside the road.

Besides eating tree and shrub bark, leaves and twigs, they enjoy eating aquatic plants in ponds and streams. This can have a downside for them. Sometimes, they unknowingly eat snails while foraging and the snails can carry parasitic brain worms.

In Gardiner, we also often saw mule deer (Odocoileus hemionus). They can be distinguished from white-tailed deer by their large ears, which measure about 75% of the length of their heads!

They also have a white tail with a black tip, while white-tailed deer lack that feature.

I found them to have a sweet face.

The final ungulate that we had the pleasure to see at Yellowstone were the fast-footed pronghorn antelopes (Antilocarpa americana).

These small-hoofed creatures are not as fast as cheetahs but can sustain their speedy gait for a longer period of time, reaching speeds of up to 60 mph.

The pronghorns not only travel rapidly; they also may travel for long distances. During the winter of 2011, monitoring of a pronghorn herd showed that they had achieved the longest terrestrial migration in the continental USA (not counting Alaska).

While both sexes have horns, those of the female pronghorns are mere bumps, while the males display unique backward-pointing horns that grow up to 12 inches long. (The one grazing below had impressions in the fur on its back that looked like claw marks to me!)

According to the Natural Resources Conservation Service of Montana, “Pronghorns existed in North America at the same time as predators like the dire wolf, saber-toothed cat, and American cheetah, all of which are long extinct. Scientists believe the pronghorn’s excellent vision and extreme fleetness are adaptations to survive these super predators.”

It’s fascinating that so many of the animals living in Yellowstone National Park have been in this area for thousands of years. An upcoming blog will feature smaller mammals after taking another visit to thermal attractions in the park. Before that, I’ll post a couple blogs about some of the wildlife I’m seeing here at home. 😊

Love me some hawks

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3 red-tailed hawk PB074118© Maria de Bruyn res

After focusing mostly on the genus accipiter hawks in my last blog (especially the Cooper’s), I’d like to share a few more photos of buteo hawks that are common where I live. Taken over the past 4 years or so, the photos will vary and show them in various seasons.

The buteos are larger birds than the accipiters and somehow seem a bit more relaxed to me than the feisty accipiters.

1 red-tailed hawk P9199892 © Maria de Bruyn res

The red-tailed hawks (Buteo jamaicensis, above) are beauties as adults with dark red tail feathers. I tend to see them most often when I am away from home, visiting fields and natural areas. Frequently, I spot them when they are hunting. Their diets are rich and varied since they see almost any small animal as a potential meal. That includes rodents, rabbits, reptiles, fish, amphibians, invertebrates and other birds.

2 red-tailed hawk P9199889 © Maria de Bruyn res (2)

 

Those dietary choices mean that I regularly see them being chased by other birds, especially in the spring when the other birds want to protect their nestlings from the predatory beaks of the red-tails. Crows especially can get very raucous and angry when red-tailed hawks are near their nests.

8 red-tailed hawk P4159552© Maria de Bruyn res

9 red-tailed hawk P4159557 © Maria de Bruyn res

 

The red-tailed hawk below was being chased away as s/he flew away with a squirrel.

11 red-tailed hawk P5134700© Maria de Bruyn res

There are 14 recognized sub-species of red-tailed hawks, which vary in color and range. In the area where I live, we have many Eastern red-tailed hawks, but last year I spotted another type flying over farmland. I asked experts from a raptor identification group for some assistance in describing it.

4 red-tailed hawk PB243087© Maria de Bruyn ed

One expert remarked: “This is a juvenile by the monochromatic brown tones, spotted bellyband and lack of dark terminal band on the wings….As a juvenile there is more overlap in phenotype than in adults, and often we cannot identify them to subspecies level.” She went on: “…this bird could be either a slightly heavier marked Eastern (borealis) or a Northern (abieticola). To me it is not heavily enough marked to be a slam dunk abieticola and I would probably not assign a subspecies to it.”

5 red-tailed hawk PB243137© Maria de Bruyn ed sgd

I asked if that meant that a Northern red-tailed hawk could be found in North Carolina and not just the Eastern sub-species, so I could start watching for those distinctions. She responded: “only in winter and probably not overly often that far south, but certainly worth keeping a look out for them.” I haven’t seen this hawk again to my knowledge.

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One of my favorite portrait photos (below) is of a red-tailed hawk. Taken in 2015, the bird flew across a field to perch in a tree right next to the path on which I and four other people were walking. S/he had seen a hispid cotton rat crawl into the vegetation underneath the tree. My birding companions walked on but I stayed and after 20 minutes or so, the hawk suddenly dropped down and snagged the rat, which must have had a terrifying wait at the end of its life. The hawk was very handsome though.

13 Red-tailed hawk DK7A6468.© Maria de Bruyn res

While the red-tailed hawks are impressive, I have a softer spot for the red-shouldered hawks (Buteo lineatus). Somehow they look less fierce and a bit sweeter to me.42 red-shouldered hawk P1280192© Maria de Bruyn res

I see them carrying out all kinds of behaviors. Sometimes, they are just flying overhead, showing off their red shoulders as they travel aloft.

14 red-shouldered hawk PC089000 © Maria de Bruyn res

They often perch high in trees to survey their territory.

15 red-shouldered hawk P2032292 © Maria de Bruyn

16 red-shouldered hawk PB148090© Maria de Bruyn sgd res

 17 red-shouldered hawk PB148081 © Maria de Bruyn res

18 red-shouldered hawk P4256997© Maria de Bruyn res     19 red-shouldered hawk P4256970 © Maria de Bruyn res

Tree tops often serve as a place to cuddle up when it is cold.

20 red-shouldered hawk P1128630© Maria de Bruyn res sgd

21 red-shouldered hawk P1128629 © Maria de Bruyn res sgd

They seem to enjoy preening when high up on snags at all times of year.

23 red-shouldered hawk PB043026 © Maria de Bruyn res

22 red-shouldered hawk PB043004 © Maria de Bruyn res

24 red-shouldered hawk PC103338© Maria de Bruyn res

A snag can be a place to call out to mates.

25 red-shouldered hawk PA074393© Maria de Bruyn res

 

And a level branch is a good place to mate.

26 red-shouldered hawk P3118052© Maria de Bruyn

Sitting very still, they scan the ground to spot prey, which they often capture by dropping straight down to kill it in a fast strike. Their diet is varied, including many types of rodents and mammals such as squirrels, mice, chipmunks, voles. They also attack birds up to the size of jays, grouse or pheasants.

28A red-shouldered hawk PC204514 © Maria de Bruyn

 

When I’ve seen them snag prey, it has usually been smaller prey such as frogs, lizards, snakes and other reptiles and amphibians. A pair of red-shouldered hawks living at an urban park in a nearby city must really enjoy the crayfish that are abundant in the wetlands.

28 red-shouldered hawk PC204381 © Maria de Bruyn res

These hawks will perch on many handy lookout posts when surveying the ground for prey. This one sat on a feeder at the local public library, suddenly flew a short way to drop down into the leaves and brush under nearby trees and seemed to be wrestling with a rodent of some kind. S/he left without the prey, however.

29 red-shouldered hawk P1300684© Maria de Bruyn. res

30 Red-shouldered hawk P1300812 © Maria de Bruyn res

 31 red-shouldered hawk P1300816 © Maria de Bruyn res

In my yard, a resident red-shouldered hawk not only sits on branches but occasionally on a nest box, to the dismay of nearby songbirds. One ate all the large green frogs in my pond.

32 red-shouldered hawk P4257137 © Maria de Bruyn res

At a small public park in a neighboring town, I watched a red-shouldered scan the field below intently for quite some time. The raptor then surprised me by dropping swiftly down, snagging something small and flying up to another tree to eat.

33 red-shouldered hawk P4106575 © Maria de Bruyn res

It wasn’t until I enlarged the photos I took that I saw the bird had gotten a large worm. (When I posted the photo on facebook, a witty commentator remarked that he was collecting bait to go fishing!)

34 red-shouldered hawk P4106576© Maria de Bruyn (2)

35 red-shouldered hawk PB180186© Maria de Bruyn (2)

Occasionally, they may be injured. This young hawk was perched in an out-of-the-way spot in a park and when I posted these photos, a commentator remarked that the bird looked injured with a wing out of place. She suggested I contact a rehabilitator but the bird eventually flew away seeming to be ok.

 

36 red-shouldered hawk PB180215© Maria de Bruyn res

37 red-shouldered hawk PB180192 © Maria de Bruyn res (2)

While I know these raptors can be just as fierce as the other hawks, I do tend to think of the red-shouldered hawks as having sweet faces. Having watched them tend to their young, I know they can be very devoted parents and I always enjoy seeing them!

43 red-shouldered hawk P1280223© Maria de Bruyn res

Final note: “I love me some hawks” is not a title I would have chosen some years ago, but I liked it for this blog as it indicates —to me —enjoyment of something. I decided to look up where the phrase came from and ended up with several explanations: 1) an ungrammatical expression that might be associated with African American vernacular or with the rural areas of the southern US states; 2) an annoying phrase usually used by the middle-class; 3) a slang way of saying ‘I really love’; 4) a novel grammatical structure indicating “I always like” something. Kinda like the middle voice in ancient Greek. Well….at least I learned something new today. 😊

39 red-shouldered hawk PC100502© Maria de Bruyn (2)

Next blog – no birds but interesting creatures nonetheless!

Wrestling with your food – not for me!

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Our 2021 winter weather in central North Carolina has been one of the wettest on record so far and is set to top the list by the end of the month. But occasionally we have had some sunny, albeit cold, days to everyone’s delight. On one recent walk on an unusually sunny day, I saw a beautiful little syrphid fly flitting about the forest floor and caught a fleeting glimpse of an Eastern rabbit, but that has been it for non-avian species except for the deer, squirrels and chipmunks in my yard. So my focus has continued to be on the more bountiful birds.

On successive visits to a pond in a neighboring town, mostly to watch the hooded mergansers, it was noteworthy to see that a single ring-billed gull (Larus delawarensis) had taken up residence. S/he spent a lot of time atop one of the parking lot streetlights at the pond’s edge. It gave a perch for a good overview of the water and its residents.

The bird is usually alone when I see him/her. They are sociable birds, however, and it’s interesting that, in some cases, two females will share nests and raise their two broods together.

 

I’d seen her/him catch fish there before and noted that the bird never just alighted, positioned the fish and swallowed it quickly. Perhaps this is because it has a broad diet and has learned to eat its varied foods differently.

Not only do they devour fish, insects, earthworms, rodents and grain; they also will scavenge people’s food if they can get to it, for example, on a beach or in a fast-food parking lot.

This yellow-legged gull will fly around the pond from time to time, looking quite beautiful in flight.

  

S/he doesn’t go fast, although they can reach speeds of up to 40 mph. Rather this bird soars quietly in circles scanning both the water and its surroundings.

Recently, I watched this gull catch a fish and then take a long time to actually eat it. First, the bird spent some time positioning the fish just right in its beak.

Then it began dunking the fish underwater and slapping it on the water as well.

Was it trying to kill the fish before consuming it?

After doing this for a while, the gull suddenly picked up the fish, flew up into the air and dropped it in the water.

Next, it turned tail and dove head-first into the pond, likely hitting, stunning and perhaps drowning the fish with this maneuver.

A Cornell University website says that adult ring-bills “play” by dropping objects and then catching them mid-air, perhaps as a way to practice their hunting technique. But in this case, that didn’t seem to be the case.

The gull still didn’t eat the prey right away, however.

S/he kept hitting the fish and moving the aquatic meal around in its mouth.

A couple times it looked like the fish was positioned just right for swallowing.

And then, the re-positioning continued.

Finally, after some time, it looked like the bird had finally ingested the meal and s/he took off again.

It was an interesting observation of animal behavior – my favorite way of spending time on nature walks. And it will likely remain a bit of a mystery as to what the ring-bill gull’s intentions were in carrying out these moves. 😊

A third look at our 2020-21 “superflight” irruption – red crossbills

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As mentioned in my last couple blogs, finches that usually reside in Canada and the northern USA have come south this year because of a dearth of food in their usual habitats. One of the factors contributing to the shortage is the varying cycles in which cones, seeds and fruit ripen among different tree species.

Not every tree produces an equal amount of seeds or berries every year; for example, this year my red cedars didn’t have very many juniper berries and by the time the cedar waxwings arrived, the American robins (Turdus migratorius) had already cleaned out the crop. Periodically, many of the different tree species up North have low seed production at the same time, so that birds who eat different kinds of crops all need to go elsewhere for sustenance in the winter.

An interesting speculation from scientists in the Finch Research Network is that this synchronized low seed production evolved as a means of limiting food supplies for seed-eating (red) squirrels who could reproduce greatly and then wipe out all the seeds so that no new trees would grow. Jamie Cornelius, a researcher at Oregon State University, explained that “birds are mobile, and can find cone crops somewhere else,” while the sedentary squirrels then need to curtail their reproduction. In addition, some birds have evolved biological processes that make it easier for them to cope with food scarcity.

Red crossbills (Loxia curvirostra, called common crossbills in Europe) molt quite slowly, losing only a few feathers at one time, which makes it possible for them to fly elsewhere at any time in search of sustenance. They are normally not migratory but will travel for food, so in December 2020, local birders were quite excited when red crossbills were spotted at a state game lands in a neighboring county.

I was not enthusiastic about going to a hunting zone but had heard that the duck hunters were usually only busy early in the morning. So I donned my bright orange vest and ventured out on the two-mile walk to the spot where the crossbills had been seen. I waited around for a couple hours but they didn’t show, although I was looking for the reddish males and yellow females to make an appearance.

I didn’t give up. On my fourth visit to the game lands, I finally saw the crossbills (although I didn’t realize it immediately as they were so far away and my cataracts make seeing anything distinctly at a distance quite difficult. It was only after I enlarged one photo on the camera that I saw what they were! Remember, you can see a photo larger if you click on it and then back arrow to the blog).

I first thought perhaps some grosbeaks had flown in, so I focused as well as I could on the distant trees and took photos. I was thrilled to see that I had finally photographed those elusive birds – giving me a “lifer” for 2021. 😊

Sometimes it’s not easy to understand why a certain bird species has a particular common name. For example, many people would call a red-bellied woodpecker a red-headed woodpecker because the red on the head is much more noticeable than the hue on its belly. But the crossbills exemplify their common name quite accurately with their upper bills that curve down over their lower bills. A good view of their beak can be seen at the All About Birds website.

At first sight, one might think that this beak arrangement would make it difficult for them to eat, but this morphological adaptation means that they can extract seeds from conifer cones that are still closed, which other finches cannot do. Their bill structure makes it possible for them to hold onto a cone, pry it open with their beak and then take out the tightly-packed conifer seeds with their tongue.

This specialized anatomical feature does restrict the crossbills’ diet somewhat. They do eat some other seeds, berries and insects from time to time and they also ingest grit and sand from time to time as having these substances in their crop helps them to digest the conifer seeds.

What also makes these finches very unusual is that there are at least six – and perhaps as many as 11 – sub-species in North America who differ in the size and shape of their beaks and the type of calls they make. Their unique vocalizations has led to each sub-group being designated as a “call type” and each type feeds on a different conifer species. They move about in groups and call to each other while flying from tree to tree. Some scientists think they may be communicating about the feeding possibilities in each cone-laden tree they pass!

Another behavior that is distinctive for the red crossbills is that they breed at any time of the year, whenever sufficient food supplies are available. When a female and male form a breeding pair, they imitate one another’s flight calls so as to keep track of one another.

 

Unfortunately, unlike other irruption species such as evening grosbeaks and pine siskins, the red crossbills are rare visitors to bird feeders.

When I heard that crossbills had been seen at a game lands area much closer to my home, I made a couple more treks in hopes of spotting them. The first day I was incredibly lucky as I was the only person visiting the reserve and could walk at a leisurely pace in quiet fields except for the chittering of multiple bird species, including a hermit thrush.

Unfortunately, I didn’t manage to see any crossbills flying overhead. Another visit to this nearby game land was shortened considerably when I discovered it was quite noisy with two hunters accompanied by a pack of baying hounds who were yowling very loudly and frequently. I high-tailed it out of the reserve and resolved to be happy with my one and only crossbill sighting (so far). Hopefully, one day I’ll be able to see them more closely – something to which I can look forward with great anticipation!

Hopping into springtime

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I’ve been planning new blogs for quite some time; then I keep taking new photos that will fit into them and the blog writing gets delayed. But two days ago, I saw such a cool natural event that I resolved to produce a blog quickly and here it is!

One welcome feature of springtime is that many insects emerge from their over-wintering spots. Some are bugs we dislike (mosquitoes, ticks and chiggers), but others are fascinating and wonderful members of our natural systems. Pollinators like this spicebush swallowtail (Papilio troilus) keep our gorgeous plants and important food crops going and many bugs provide other wildlife with meals.

On my trip to Costa Rica last year, our guide not only pointed out birds but also some mammals and insects. He had developed an interest in treehoppers, a group of insects with about 3200 species worldwide that specialize in eating plant sap. He was unable to find any to show me, but I resolved to keep an eye open for them when I returned home. I had forgotten that I had seen my first one the year before, a pretty green Ceresini species.

As I stared at plants during nature walks, I was lucky and managed to find my first treehoppers when I was actually looking for them. These were of a dark-colored species (Acutalis tartarea) that favors the sap of black locust trees, sunflowers, goldenrod and ragweeds.

The treehoppers, which are related to leafhoppers and cicadas, are popular with some entomologists because many species have elaborate “helmets” at the top of their heads. I got to see my first example of this type on my recent walk when I happened to find a young oak tree with numerous nymphs and recently eclosed (emerged) adult oak treehoppers (Platycostis vittata).

The mother treehopper is known for staying close to the nymphs to protect them against wasps and other predators.

The hoppers get plant sap by piercing plant stems with their beaks. The nymphs have extensible anal ducts that deposit the sap away from their bodies. This is important because the concentrated excess sap, called honeydew, can get moldy.

 

                              

The honeydew attracts ants, which like the sugar-rich liquid, so the hoppers and ants have a mutually beneficial relationship.

Just how the helmet develops into an unusual shape has been a source of investigation. One team of entomologists theorized that the helmet was formed by body parts that were actually modified wings. Another researcher countered that this was impossible and that the helmet was an unusual pronotum — the foremost dorsal section of the thorax. More recently, a third group of evolutionary biologists postulated that the helmet is indeed a section of pronotum but one that developed with the aid of genes that code for wings.

In various species, the pronotum has developed into a quite unusual and oddly shaped appendage; examples can be seen in this article. When the helmet resembles a plant thorn, it is thought to aid in camouflage.

When I discovered the group of oak treehoppers, one was just in the process of emerging from its nymph form. A friend who saw the photo remarked that it reminded her of the film Alien but this process was slow and deliberate and not a heart-thumping explosive emergence as shown in the movie.

As you can see, the oak treehopper is quite a beautiful insect with its pristine white body decorated with pink/red stripes and hints of yellow. They made me think of mints and Candy Stripers (a sign of our times when almost anything makes me think of health and health-related concerns. For younger readers: young female volunteers who work under nurses’ supervision in hospitals used to wear pink and white striped smocks and thus got the name Candy Striper).

Not all the adults had the horned pronotum; some had rounded heads.

This close-up of a hopper’s face could evoke all kinds of thoughts. I thought it looked as if it had a pig’s snout. Another friend thought it looked like a grumpy old man. What do you think when you see this visage?

Or about this one, with its head upside down? (It looks a bit more “innocent”, don’t you think?)

In any event, I found these insects just adorable and I felt very privileged to have had the chance to see them emerge into adulthood. It turns out that in this species, older individuals may change color, turning a dull brown or green color. Some mottled forms may be blue with yellowish spots. It would be interesting to see those forms as well one day – or perhaps one of the other treehoppers with a different fabulous helmet!I hope you, too, are able to get out in nature during these social distancing times so that you can connect with the wonderful wildlife around us!