Life in the mountain shrub community

Another hike, a bunch more fun photos. One of the big reasons I like walking is because I go slow enough to see interesting things.

Side-blotched lizard.

If I’d know blotchiness on the side of the lizard would be diagnostic, I would have tried to get a shot.

The slit on the lizard’s head is not a gill, as I keep thinking it is, even though I know better. Reptiles don’t have gills, they have nostrils and breath air.  The slit is the lizard’s ear.

 

Yellow-breasted chat.

Yellow-breasted Chats look like lemon-breasted robins. But instead, they are overgrown wood-warblers, a family that includes birds like the Virginia warbler or Wilson’s warbler. Don’t recognize the names? That’s because they are too small to see easily, usually around 5 inches long, or smaller, and they prefer denser forest. Yellow-breasted chats, on the other hand, are around 7 1/4 inches long — robin-sized — and live in open shrubland.

Fremont geranium

Fremont geraniums were all along the trail. Very nice.

Monarch Butterfly Migration

Thanks to the nice weather, I worked out in the yard for a good bit last weekend. As I worked, I saw and heard our normal back yard wildlife — feisty squirrels, black-capped chickadees, house finches, Northern flickers, dragonflies and big yellow swallow-tail butterflies. Then I saw something unusual — an orange butterfly. I assumed it was a Viceroy, because it flew right past the big patches of milkweed we’ve let grow for the Monarchs that might wander through our yard (Bees and Butterflies).

Then I saw another. And another. None of them were landing anywhere in the yard, but I decided to try to photograph them anyway. Maybe one would alight just long enough for me to snap a shot.

As I watched them more closely,  I began to have a niggling feeling that maybe I should check my butterfly identification books. In the meantime, I took a few photos.

Monarch butterfly

Viceroy butterfly

Monarchs are orange with black stripes. They differ from very similar Viceroys in that Viceroys have a stripe along their lower wing. Otherwise, they are almost identical. So the photo on the left, taken in our back yard, is a Monarch! I’m glad it stopped by.

Starting in March, Monarchs migrate from Mexico and Southern California to Canada every year, reaching their northern limits in late June. We get our first Monarchs about the same time.

Monarch feeding on milkweed in our backyard.

There are lots of astonishing facts about Monarch and Viceroy butterflies. One fact about the Monarchs is that, although they migrate long distances every summer, no one butterfly goes the whole distance. Instead, the overwintering generation heads north in early spring. They mate, lay their eggs and die somewhere along the way. The next generation of monarchs hatch and head north. They mate, lay their eggs and die somewhere along the way. It takes at least four generations to get to the northern-most point in the Monarch migration! The fourth generation then makes the return trip south, and overwinters in the same trees its ancestors did last year. As with other butterfly species (Painted Ladies migrate across North America!), nobody knows how they do it.

You can watch Monarchs as they travel at this website: Lerner Monarch Butterfly Migration Map Spring 2018. They even have a site where you can report your observations! What to Report

 

 

Painted Ladies Part Two

After seeing thousands of painted lady butterflies a couple of weeks ago, I thought they were done for the season.Painted Ladies migrate across North America!

Wrong! There are still so many migrating through the Denver area, that, when they fly a bit higher, they are visible on radar!

NWS Boulder‏Verified account @NWSBoulder Oct 4 4/4: Migrating butterflies in high quantities explains it. Today, the butterflies are staying close to the ground. #cowx #Science

How cool is that?

Pika Patrol, Part Two

My husband, my son, his girlfriend and I went up to my Pika Patrol (Pika Patrol, Part One) site over the weekend. After thrashing about a bit learning how to use the GPS, we found the appointed talus slope. Located on the north shore of Grand Lake just south of Rocky Mountain National Park, researchers had determined that pika had been present there in the past.

The four of us searched the talus for half an hour. We listened for pika calls — they sound like the squeaky toys they resemble. We heard sharper chipmunk calls.

You can tell this is a chipmunk by the lines on it’s face. Their call is a sharp bark.

We looked for piles of hay drying outside their dens. We found pine needles.

Instead of fresh grasses and flowers, we found old pine needles.

We saw the distinctive orange lichen that indicates where pika have peed. The extra nitrogen in pika urine allows this particular lichen to grow. But the lichen had a dry, flaking appearance.

The orange lichen looked dried out and flaky. Spider webs criss-crossed many crevices.

After half an hour of searching every nook and crevice we could find, we had to admit that there were no longer pika there.

We weren’t the only ones to come to that conclusion. Every pika monitoring site has three teams that visit it each fall to verify each other’s results. Nobody found any current signs of pika at this site.

At about 9000 feet, the Grand Lake site is the lowest site that the Pika Patrol monitors. According to a map I got from the National Park Service, this area burned in 1879, opening up the forest canopy. Pika were able to move down, and occupy this site for a time. But as the trees grew back, the meadow where the pike foraged turned back into forests, and trees grew in the talus field itself.

A couple of my handsome and lovely assistants hold signs stating where we started our search, and which direction we were facing. There were aspen, spruce and lodgepole pine sprouting up around the edges of the talus slope.

If summer temperatures have gotten higher, this would have impacted the pika as well. At temperatures of 75o or above, pika must retreat to their burrows, rather than gather forage. For a site like this one, where grasses and flowering forb plants were decreasing anyway, the combination might have been too much.

It was disappointing not to find pika, but negative results are science, too.

 

Painted Ladies migrate across North America!

This morning, my husband and I stepped out of our house to walk our dogs, and were mobbed by Painted Lady butterflies!

There were dozens in our yard, sipping nectar from sunflowers and oregano.

As we walked through the neighborhood, the numbers increased. They were everywhere. Delightful!

Painted ladies are on every continent except Australia and Antarctica. (Painted Lady Vanessa cardui) Like the much more famous Monarch butterflies, Painted Ladies use multi-generational migrations. They start in Mexico, and take several generations to move into Canada, then turn around and take several generations to get back to Mexico (at least I think that’s how it works…) They do the same thing in Europe, migrating to tropical Africa. Nature Nut: Have you seen the painted ladies ‘invasion’? Nobody knows how they know where to go.

They do this every year. Some years, the migration is bigger. And some years, like this year, the migration is enormous.

Happy to have seen it.

Pika Patrol, Part One

What do you do when you are forced out of your home? How do you find another place to live, when the sites you need are already full?

American Pika, small rodent-like rabbit relatives who live in the alpine tundra of the Rocky Mountains, are facing this problem as warmer temperatures force them ever higher. The problem is that there is only so much “up” that pika can go.

Pika are small critters most closely related to rabbits. They have been called “unmercifully cute”, which is probably an understatement.

I spent Saturday in the alpine tundra on Loveland Pass (elevation 11,990 feet, or 3655 m), west of Denver, with scientists from the Denver Zoo and researchers from CU Boulder, learning how to measure pika habitat.

Pika are exquisitely adapted for life in the alpine tundra, where winter temperatures are often 0o F (-18o C), and winds average 50 mph (80 kph).  Storms bring blows of 100 mph (160 kph) or more, and drop to -40o F (-40o C). Only a very few animals stay in the tundra through conditions like that: Bighorn sheep, mountain goats, ptarmigan, marmots — and pika. And what’s more pika are active all winter long.

Master of all it surveys — a territory of about 12 meters, or 36 square feet.

How do pika survive these extreme conditions? In a sense, they don’t; they avoid them. Pika live beneath six feet (2 meters) or more of snow. At these depths, the temperature is about 28o F (-1 C) and dead calm. The little critters run through tunnels among the talus rocks to graze on leftover alpine plants. But there aren’t enough of these low-growing plants nearby for pika to survive the winter. So during the fall, the animals gather vegetation and stash it in rock crevasses to build haystacks. They then eat the haystacks throughout the long winter.

A pika gathering forage for it’s hay stack.

The beginnings of a pika hay stack. The Zoo people tell us that by the time the pika is finished, this little crevice will be overflowing with a bushels-worth of hay — about 62 pounds (28 kg) of forage! It takes pika 14,000 trips to gather this much hay.

Here’s the problem for pika: their body temperature is about 104o F (40o C), and they have dense fur to hold this heat in. While this helps them stay warm through the winter, it means they are vulnerable to overheating when temperatures hit 70o F (21o C) in the summer. They can survive short warm spells by descending into the passages beneath the talus. But if pika are chillin’ in the rocks, they aren’t gathering forage to make hay for the winter. As global temperatures rise, pika can overheat, or they can starve. Tough choice.

You can get a sense of how dense pika fur is in this photo.

The one thing pika can’t do is move. Their habitat is limited to the tops of  mountains above tree line. If it is suitable for a pika, one already lives there. There isn’t any more.

Scientists at the Denver Zoo want to know how pika are responding as global temperatures rise. So they called for volunteers to come learn how to measure pika habitat. Over forty people showed up at the top of Loveland Pass Saturday morning. After leading us up the alpine trail for a couple of hundred feet, we all sat in a learning circle.

A Denver Zoo staff person explains how the survey works.

We were a bunch of strangers — retired biologists, teachers, a family who wanted to do something together, longtime hikers — but all were passionate about pikas, or Citizen Science. People came prepared, and asked good questions: How big is a pika’s territory? What makes good territory? How did the zoo pick the sites?

We get answers to our questions.

Biologists have a couple of ways to study animals in the field. They can watch them, which takes a lot of time and yields limited information. They can catch them, which is stressful for everybody involved. Or they can study bits of the animal that are left behind — hair, feathers, and even more exciting — animal feces. As a matter of fact, biologists tend to get a little fixated on scat. The animal has no further use for it, and it can tell a scientist a lot.

So we learned how to look for scat, recognize that it was fresh, gather it, and send it to the researchers.

The orange lichen on the foreground rocks is a type that needs more nitrogen. It thrives where pika pee, which makes it a good indicator of pika dens. In the center of the photo is a small pile of pika scat, waiting to be collected by Citizen Scientists.

The researchers can break the little pellets apart and see what the pika are eating. Flowers are higher in protein for growth, while grasses are higher in carbohydrates that provide energy. Another thing that pika scientists can measure is the amount of stress hormones in the scat. If the animals are stressed, they are probably having a harder time surviving. The big reward, though, may be the DNA gathered in the scat. DNA can tell scientists who is moving where, and who doesn’t survive.

Pika fecal pellets glued to the top of a rock with urine.  See? I’m fixating.

As the morning progressed, I and the other volunteers put what we had learned to the test. We measured, we crumbled pika poop between our fingers. When we found a hay stack on our own, we whooped with excitement. I had a wonderful day at 12,000 feet, looking for pika with total strangers.

But the funny thing is, they didn’t feel like strangers. As I looked around at the people who were passionate enough about this Citizen Science project to volunteer to spend the day learning how to find pika poop, I saw that they people were just as enthralled with science as I was. I thought “This is my tribe. These are my people.”

So now that I’m trained, it’s time for me to go monitor some pika habitat. I’ll probably wait until September, so that the pika have a chance to gather some hay, and I’ll have a better chance of finding them. But I can hardly wait.

Colorado Monsoons

The weatherman is calling for thunderstorms tonight, as “monsoon moisture returns to the state.”
I always feel weather forecasters are a little presumptuous calling summer moisture in Colorado monsoons.  I mean, although we can have the occasional gully-washer, our piddly precip is nothing compared with the six months of torrential rain that most people normally think of when they hear the word monsoon.
But according to weather people, “a monsoon is a wind that changes direction with the seasons”. By that definition, the Southwest, with Colorado on it’s northern edge, has a monsoon.  Summer heat on the desert of Southwest Arizona, California, old and New Mexico warms the air there, causing it to rise.  This creates a vacuum, called a low pressure cell.  The low pressure sucks moist air from the Pacific and Gulfs of California and Mexico, bringing storms to the west and southwest part of the state and

You can see the center of the low pressure system as a lack of clouds in Chihuahua Mexico. This system spun up into the Front Range of Colorado, where it dropped over half an inch of rain.

occasionally onto the plains. In winter, the Southwest deserts cool, and create a high pressure cell that can keep moisture out.
These summer storms don’t compare to the classic monsoons of Asia and east Africa, but Coloradoans are usually glad to get moisture in any form.