Birds of a Feather: Double-Crested Cormorant

Great Blue Heron and Double-Crested Cormorants at NAS Pensacola

On a dreary January day strolling the waterfront at Naval Air Station Pensacola while waiting on my son to check-in for the week, I was treated to a variety of birds going about their daily business.  On one pier, a heron and a bunch of double-crested cormorants were trying to stay dry.  Cormorants have no oil glands to help waterproof their feathers, so they have to air dry their feathers after swimming and are often seen spreading their wings to do so.  The double-crested cormorant is named for the two tufts of feathers on its head during breeding season.

Double-Crested Cormorant in the Eagle Pool at Loess Bluffs NWR

Cormorants are very distinctive swimmers.  Riding very low in the water, their heads and upper backs are the only things visible in the water.  They dive quickly and can stay submerged for up to 70 seconds and reach depths of about 30 feet.  Small fish can be swallowed under water, but most are brought to the surface before they are swallowed.  In addition to fish, they may hunt frogs and salamanders, as well as crayfish and crabs.  Indigestible materials such as bone and crustacean shell are regurgitated in a pellet like those of owls.

I first remember hearing/reading about cormorants on Captain Kangaroo in "The Story About Ping" by Marjorie Flack and illustrated by Kurt Wiese.  It stars Ping the Duck, who lives on a wise-eyed boat with his family and human master on the yellow Yangtze River.  The master lets the ducks out to feed and when they come home, master swats the last duck on the backside.  Ping, being chronically late, decides to hide rather than go home and get his spanking.  The next day he sees a lot of boats, but not the wise-eyed boat.  One of these boats has black fishing birds with hooked beaks.  These are cormorants.  The bird would catch a fish, then return to the fishing boat, where the human master would give them a bit of fish for pay.  (What the book isn't telling you is that the fishermen tie snares around the necks of the cormorants or place rings around their necks to keep them from swallowing big fish - learned that in elementary school).

Ping dove for fish, but surfaced far from the cormorants, and followed a trail of crumbs to a houseboat, where Ping was promptly caught, trapped in a basket to await becoming supper.  SUPPER?!! No wonder we were so screwed up as kids.  I can understand a witch eating bad kids, but cute little ducks?  Yeah, I know.  As an adult, I found out that ducks are delicious.

Anyway, the little boy on the boat felt sorry for Ping, and let him go.  Ping found his way home, and swam towards his family, only to find he was going to be last again.  This time, however, he accepted his swat. Not real clear about the moral of the story, but it made an impression.  I remember this story from almost 50 years ago.  It has real staying power - first published in 1933 and made the National Education Associations "Teachers' Top 100 Books for Children" list in 2007.

Narrated Story of Ping

Double-crested cormorants overwinter in the United States south of Missouri, especially coastal areas.  These birds breed in the north-central United States and south-central Canada.  In the mid-central United States, these birds make stopovers at waterholes during Spring and Fall migrations. 

Range Map of Double-Crested Cormorant

Double-Crested Cormorant Sunning at Loess Bluffs NWR

Bodacious Botanicals: Dotted Horsemint

Having studied biology on some level for more than 40 years, I have seen a wide variety of living organisms.  One of the most striking plants that I have seen is the Dotted Horsemint (Monarda punctata).  It grows to about three feet tall, with clusters of yellow tubular flowers with purple spots on the upper leaf axils.  The bracts (leaves near the flowers) turn white to lilac in color.  The stems are square, a hallmark of the mint family.  The leaves are spearhead shaped (lanceolate) to narrowly oblong and have hairs.  This plant grows in sandy soils from Vermont to southeastern Minnesota and down to Florida and Texas.  Interestingly, the dotted horsemint is missing from the Ohio River drainage.  Horsemint tends to grow in colonies, so if you find one plant, you will likely find others.

Also known as the spotted horsemint or spotted bee balm, the decorative flowers work well in butterfly gardens.  They bloom for a long time, and have showy foliage from July - October.  Pollinators include bumblebees, honeybees, plasterer bees, miner bees, wasps, swallowtail butterflies and the Karner blue butterfly.  Hummingbirds are attracted to the aromatic blossoms, as well.

Dotted horsemint has found many uses by humans through the years.  Being a member of the mint family, it produces several fragrant oils, and the Navajo used them to freshen the air in their hogans.  The plant has been used by several American Indian tribes as a medicine.  It has been used by tribes as diverse as the Meskwaki (Fox), Mohegan, Blackfoot and Nanticoke in teas and powders to relieve stomach cramps, cold, fever and flu.  Poultices on wounds can be used as an antiseptic. 

The plant produces a high content of thymol, which has known medicinal qualities.  Several mints are known to settle a queasy stomach when brewed into a tea.  Thymol can also be used to remove worms from the digestive tract, has antibacterial and antifungal properties.  Thymol has also been used as a miticide and fungicide in beehives.  It shows promise as a way of treating bacteria while reducing the incidence of antimicrobial resistance when used in tandem with antibiotics or antifungals.  Thymol also acts as a depressant through GABA-receptors, which explains some of the calming effects of herbal teas containing mints. 

This nice stand of horsemint was along the nature trail at Illiniwek Village State Historic Site in Clark County, Missouri.  This site contains the only known Illinois Indian village in Missouri.  Although the plant has a wide distribution, the first time I saw it was about 3 years ago on vacation with Nadienne. If you garden with native perennials east of the Rocky Mountains, this would be a showy addition to your collection.

Rad Critters: Eastern Collared Lizard

If you look around, you are liable to run into all manner of critters.  Some of them are especially memorable.  While walking around the country, I have often caught a bit of movement out of the corner of my eye.  Sometimes they are colorful, others not.  Some will sit still, others you'll be lucky to get a camera lens on.  On one hike in Colorado, we chased one of the prettiest lizards that I have ever seen down the trail.  The Eastern Collared Lizard (Crotaphytus collaris) males are especially colorful.

These guys are pretty big, reaching lengths up to 14 inches.  They have a bright yellow head, with a black collar at the neck and blue body.  Known as a "mountain boomer" these animals make little in the way of noise, except for the occasional squeak.  When they are threatened they scurry away or may stand up on their hind legs and run.  I never could quite get a camera focused on one of these guys on a run.

Such big reptiles like to have a warm basking space (100 - 105 degrees F) and warm weather at other times (80 degrees F) for good digestion of their food.  They are found from Missouri west into the Rocky Mountains, south into Mexico and around the south tip of the Rockies into California.  They are mostly insectivores, but may eat some fruits and vegetables.

Getting There

You can find these guys across most of the southwestern US

White Sands National Monument

Continental rifts produce some interesting geography. We have visited the Rio Grande Rift several times and found something new to see each time. Just north of El Paso, Texas and Las Cruces, New Mexico is a field of dunes composed of the whitest and finest sand you'll likely see. White Sands National Monument preserves much of one of the more unique geological features in North America.  Gypsum transported from the surrounding mountains collect in the bowl that is the Tularosa basin and forms dunes of varying heights.  The sand moves so quickly that roads have to be regularly plowed to keep the road clear for automobiles.

From sea to shining sand

The Four Corners area of the US during the Permian period

For most of its history, North America has mostly been covered by shallow epicontinental seas.  The mountains that make up so much of the landscape of the American West have been pushed up fairly recently.  The story of White Sands begins in the Permian period (299-251 million years ago).  During times of sea level rise, southern New Mexico and Arizona were inundated by ocean.  As sea levels fell, and the sea shallowed out or became cut off into inland salt lakes the water would evaporate, concentrating the mineral contained therein.  These crystalline materials are called evaporites. Calcium sulfate precipitates into a mineral called gypsum.  Several episodes of sea level rise and fall eventually formed the Yeso formation, some 1500 feet of gypsum rock that can be seen in the surrounding mountains.

Uplifting experience

Plants helping to anchor sand dunes in place.  San Andres Mountains
form the backdrop

The manufacture of the Rocky Mountains was very complex, and this feature is related to part of that story.  As Pangaea broke up during the Jurassic, oceanic crust of the Farallon plate began to subduct (sink under) the western edge of the North American plate which was located at about Utah at the time.  As the Farallon plate sank under North America at an angle of about 50 degrees, it pulled ocean plateaus and islands to the western edge of North American, fusing them with the continent, forming the land in Nevada and California.  This new land pushed the subduction zone further to the west.  Collision of oceanic crust with North America produced the Sevier orogeny, pushing up mountains from Canada to Mexico, including in Idaho, Utah, Wyoming and Nevada.  In this episode, pressure from the eastward moving ocean plate plus heating caused the crust to shorten and the sedimentary layers to fold and break along weak planes.

Franklin Mountains show deformation from Laramide orogeny but
are mostly built by rifting processes.  See how the rock layers tilt?

About 70-80 million years ago, the Farallon plate began to move more horizontally.  This caused the crust to fold into a series of ridges and basins, and the crust broke along deep fault lines produced during the breakup of Rodinia.  Blocks of crust with basement rock cores were tilted upwards during this orogeny (the Laramide orogeny), which extended deeper into the interior of North America than had the Sevier event.  The Black Hills mark the eastern boundary of this mountain building episode.  This episode ended as the Farallon plate cooled, became denser and started sinking again about 35-55 million years ago.

Drift in the rift

32-34 million year old pyroclastic flows and lava
Organ Mountains on east side of Rio Grande Rift

An upwelling of magma generated a period of tremendous volcanism throughout the southwest US starting about 35 million years ago and ending about 20 million years ago.  The magma produced a thinning of the crust and it extended up to 50% in the late Oliogocene.  The Rio Grande rift started forming about 30 million years ago.  As the crust extends, it cracks along pre-existing faults and the block on one side of the fault drops in comparison that on the other side.  The rift trends northwards and extends from Chihuahua State, Mexico into Colorado.  The thinning crust resulted in further subsidence; most basin-building took place in the last 10 million years.

Rio Grande/Rio Bravo south of White Sands

The first period of extension, during the Oligocene, lasted from 30-19 million years ago or so.  The second period of extension began during the Miocene, about 17 million years ago and continues to this day.  The area of rifting is at least 180 miles wide, and stretches about 1.5 mm per year from east-west in Colorado to 2.5 mm per year in northern Mexico.  The basins that make up the visible portion of the rift average 30 miles across.  The rift valley is partly filled up with sediment that has accumulated to a depth of nearly 5 miles.  The Rio Grande River occupies the rift valley.

Carrizozo lava field, LandSat 7 NASA photo

Evidence of the volcanism associated with rifting abounds in the region.  Hot springs, extinct cinder cones, mountains built from lava.  Lava field badlands (malpais) are present.  Just north of the White Sands is a gash of black lava, the Carrizozo lava field.  This flow of lava erupted from a shield volcano about 5,200 years ago.  The high basalt content provides the black color, and the thin consistency of the lava allowed it to flow freely down the rift valley.  There are also cinder cones in the field.  It is likely that humans were present to witness this eruption.

Part of another lava field near Grants, New Mexico forms a part of El Mapais National Monument.  Ben still gets a ribbing from our visit there when he was 5ish.  Another day.

Ice, ice, baby

Lake Otero, NPS

During the last Ice Age, glaciers did not reach this far south.  However, the climate was cool and wet.  Large amounts of rainfall would fall, percolate through the porous rocks, dissolving the gypsum in the Yeso Formation.   Spring running out of the mountains plus runoff gathered into the bowl of the Tularosa basin, forming a large lake, called Lake Otero.  Calcium sulfate would continue to increase in concentration in the low-lying lake, precipitating into crystals from time to time.  This crystallization accelerated as the climate warmed, became drier and the lake shrank.  Today, the remnants of the lake are Lake Lucero at the south end of the dune field, Alkali Flats and a playa on the east side of the dunes.

Surrounding mountains provided much of the gypsum

Gypsum.  You can blame the playa

Playa near Visitor Center.  Lake Lucero is part of White Sands Missile Range
and can only be reached in a monthly ranger-led tour.
Check website for schedule

The crytalline gypsum that erodes out of the shallow basin lake (playa) and alkali flats is called selenite.  This mineral forms thin sheets that break apart readily.  As the cycles of wind and heating and cooling break down the selenite crystals, the become a very fine white sand.  The sand drifts and gathers into dunes.  Very strong winds can lift the sand and blow it over the Sacramento mountain range, as in the NASA satellite view below.  This also gives you a good idea of the prevailing wind pattern in this part of the country.  The dunes are formed by winds blowing from southwest to northeast.

Selenite crystals at Lake Lucero - NPS photo

White Sands NM at left center, trailing gypsum dust plume to northeast
NASA photograph from Aqua satellite

Making dune

Barchan dunes towards the west side of the park

To make a dune, you need a very strong wind, sand grains small enough to be carried by the wind, and friction / resistance of some kind to get the sand to stick together somewhat.  The sand will start to pile up forming a shallow angled ramp that the wind carries sand up.  When sand reaches the top, gravity may take over and the sand grains fall down in the stagnant air behind the dune.  This side of the dune is called the slip-face.  The sand on this face tends to be looser and the slope is steeper, making it more difficult to walk up than the windward side.

A "blowout" happening just right of center
Sacramento Mountains form the background

When there is a high wind velocity and a limited amount of sand, dunes will form as barchan dunes, which are horseshoe shaped with the arms pointed downwind.  This form of dune is plentiful along the Loop Drive.  Sometimes barchan dunes unite into a line called a transverse dune.  Dunes that suffer a "blowout" often have plants covering the dune, so the denuded area travels quickly and the arms more slowly resulting in a horseshoe that points with its arms upwind and the arc downwind.  These parabolic dunes are common on the outer edges of the park, except in the west.

Rio Grande Cottonwood (Populus deltoides)
growing on top of a dune

The dunes at White Sands are relatively easy to walk upon because of the soluble nature of gypsum.  Rains will solubilize some of the gypsum, which will recrystallize and cement neighboring gypsum granules together.  This layer will also protect a groundwater from evaporating.  Plants that are trapped by an advancing dune may increase stem length to keep leaves above the level of the sand.  These plants can then tap into the protected groundwater for their own survival.  Plants such as the cottonwood that can extend roots down to groundwater are called phreatophytes

Another plant that seems adept at stem elongation is the soaptree yucca plant.  Young flowering plants may be about 3 feet tall, but by stem elongation, they may reach 18 feet.  The yucca is well adapted to a variety of climates, but they are only pollinated by one moth, the yucca moth (Tegeticula yuccasella).  At that, it is only the female yucca moth that visits the flowers of this plant, since the males complete their life cycle after mating (they die).  The egg-laying habits of this moth push pollen down into the pollen tube of the yucca flower.  Yucca moths lay their eggs in the flowers, and the young will develop in the yucca fruit, drilling through the outer skin to escape.  This yucca has a sap that contains a natural soap, which accounts for the name.

Soaptree Yucca (Yucca elata)

Radical animals

While the white sand does not get as hot as fast as darker sand, the desert is still a warm and dangerous place in the daylight.  Most animals in the desert become active in the evening, and many of them may be best evidenced by their footprints.

Beep Beep!  Roadrunners leave X shaped tracks in the sand

Lizards drag their tails behind, making a line between left and right footprints

A tweedle beetle bottle puddle bottle muddle --- bug tracks

Pioneers

Gyp nama (Nama carnosum)

When a dune has passed, the soil has a high gypsum and salt content.  Gypsophiles are plants that are specialized to living in this environment.  These plants are rarely taller than shrub size.  Most of these plants are shorter than two feet tall.  After a few generations of growth, they will enrich the soil with their decaying organic material, creating a soil more friendly to less specialized plants.

You can often spot a gypsophile in a list of plants by its name; they are often called Gyp "something".  For instance, Gyp nama is a little plant that looks like a fir tree.  It has small white flowers in the summer after rains.

Yellow Evening Primrose (Calylophus hartwegii)

Another pretty gypsophile is the yellow evening primrose.  These flowers are yellow by day, but after being pollinated by nocturnal moths, the flower wilts and becomes more orange colored.  The plant that I saw was getting a bit ratty, but it did have some nice flowers.

Not all of the plants here are strictly gypsophiles.  The sandy verbena plant is a generalist.  It can be found on gypsum flats, in interdune areas and on the dunes.  They have little pink flowers in April and May, but sometimes flower after rains in the summer into October.  You couldn't prove it by me, but the sign says that they produce a lilac smell, especially after rains.

Sand Verbena (Abronia angustifolia)

Spring Blooms in the Chihuahua Desert

The first time I visited this area, I was in El Paso for work and stayed over to take a drive out to White Sands in late May.  The second time Ben and I went when he was in middle school during winter break.  Not many blooms then.

Ocotillo (ock-uh-TEE-oh) Fonquieria splendens

Barrel cactus (Ferocactus acanthodes)

Cholla (CHOY-uh) Cylindropuntia imbricata

Yucca (Yucca elata)

Getting There

If you are coming to Las Cruces, New Mexico from the west on I-10, you can catch US-70 heading east at Exit 135 (Alamogordo) OR you can catch I-25 going north at Exit-44, then US-70 east (Alamogord - Exit 6).  From El-Paso, you can take I-10 north to I-25 to US-70 east.  Coming from El Paso, I enjoy driving through the Franklin Mountains - from I-10 take exit 22B and head toward Alamogordo on US-54, exit at Exit-29, take the first left onto Woodrow Bean Transmountain Drive (Loop 375).  If you are getting out in the sticks and going up, you've done it right.  Much of the drive through the Franklin Mountains is a state park, lots of turnouts and trailheads.  Very nice views.  This will take you back to I-10.  You need to go north once on I-10 OR take a scenic route.  I enjoyed driving the backroads to Mesilla and Las Cruces.

The national monument is surrounded by the US Army's White Sands Missile Range and Holloman Air Force Base. The US Army is not nearly as sentimental about nature and geography as we are, since they use their part of the region to test out weaponry. This is a bad news/good news thing:  the bombings destroy some features, but protection from traffic also helps preserve some features.  From time to time, missiles are flown over the national monument, making park and road closures necessary. Good thing, because missiles have fallen on the park and destroyed visitor facilities before.  Check the park website to see when closures are scheduled.   That seems to be the watch word for this park:  Check ahead, especially if you are traveling on a tight schedule or want to visit one feature in particular.  There are border patrol stations on US-70, so be prepared to stop and talk to the nice people.  US-70 may also be blocked during missile tests.  Check ahead, be prepared.

Waypoint:  Latitude 32.7803176 N; Longitude 106.1777423 W
Street Address: 19955 US-70, Alamogordo, NM 88310

Trinity Site, where the first atomic weapon was tested is just north of here and is open for visitation the first Saturdays of April and October.  Going to go there one day.

Further Reading

National Park Service White Sands National Monument Site

White Sands National Monument History

Ice Age: Where There's Water, There's a Way

The Ice Age

Wisconsin shore St. Croix River Dalles

The Wisconsin glacial period lasted from about 85,000 - 11,000 years ago.  During this time ice covered most of North America north of 38 degrees north latitude to a depth of 2 miles.  As the ice sheet melted about 10,000 years ago, the meltwater filled parts of the basins of modern Lakes Superior, Huron and Michigan.  The natural drainage of this lake was to the east, but a lobe of the glacier blocked that exit.  Water from an area of ice sheet the size of Minnesota and a mile deep filled glacial Lake Duluth until water level was 400-500 feet above the level of modern Lake Superior.

Rounded and polished boulders

When the water overtopped the hills forming a natural dam on the southwest side, the water ran in torrents down the modern Bois Brule and St. Croix River Valleys for years.  The water cut easily through Cambrian sandstones, but ran over the top of harder rock.  South of here, the rush of water cut deeply into sandstone forming a huge waterfall.  The erosive action of the water cut away the foot of the fall and marched upstream and the lip broke loose, eventually cutting into the hard basalt that would form the narrow chute we call the Dalles of the St. Croix River.  The force of the water running by here is likened by park interpreters as that of a fire hose.  Only the water was full of sand, rocks and boulders.  These can be seen in the smoothness of the rocks polished by the action of that sediment-laden water.

But Doctor Hoffman, where did the sand, rocks and boulders come from?  Wow, great question, glad you asked.  As the Midcontinent Rift formed, water and cycles of freezing and thawing wore down the basalt and the dirt filled the rift valley.  In lakes and rivers of the rift valley, sandstones and shales were deposited.  Add to that the material that was scooped out by glaciers during the ice ages and deposited at the margins of the glaciers as they melted.  Turn on the jets from an overtopped glacial lake dam, and it scours out the loose stuff just like a power washer pushing dirt across your porch or driveway.

Fun Potholes

Small pothole cut through rock

As a torrent of water runs over a rocky bed, there are areas where eddies form.  These swirling circular currents will start to scour out a depression in the rock with the sand and rocks that it moves.  If a rock rolls into the depression and cannot move out, the water may be able to rock it and roll it around, smoothing the rock into a round grindstone.  These grindstones can then swirl around the perimeter of the hole, cutting it deeper.  Interstate Park has the highest known concentration of these features and some of the deepest known potholes.

Pothole

The flow of water out of Lake Duluth may have continued for hundreds of years.  Only when the Superior lobe of the Laurentide Ice Sheet melted did the water flow downhill toward the east.  One can only imagine how much water and force was required to carve out the St. Croix Dalles and these potholes.  It must have sounded much like it would standing at the bottom of Niagara Falls.  The small pothole figured above is only about six inches across and about two feet deep, tunneling through the entire rock layer.  There are over a hundred potholes in the boundaries of the park that are much larger than this.  We were actually standing in a twenty feet deep pothole when we took the picture of the left, which shows another pothole that was cut even deeper.

Grindstone

Conglomerates

Conglomerate on rocks

Scoured potholes, grindstones, a gorge cut through tough rock, and rounded boulders all point to a huge flow of water through here.  Not just water, but water full of boulders, rocks, pebbles, and sand.  How can we be sure? As we were hiking through the woods, we came upon some rocks at least 30 feet above the current level of the water covered with conglomerate.  This mixture of sand and pebbles solidified after one of these tremendous floods and cover the rocks in places.  The water flowing out of glacial Lake Duluth would have been chock full of this stuff, ideal for cutting through rock.  The pebbles in the photograph range up to about 1 inch in width.

Creation of the Park

The basalt in this area was perfect for making gravel for building material, a business venture proposed by a group of St. Paul businessmen in the 1860s.  Public interest to preserve the scenery was piqued and influential people like George Hazzard and William H.C. Folsom led the push for preserving the Dalles.  George Hazzard was a travel agent, Chamber of Commerce chair and secretary of the Red Rock Camp Meeting Association, which pushed for the combined Minnesota and Wisconsin park idea.   Folsom led the legislative push to establish the Minnesota side of the Park.  The Minnesota side was established in 1895 and was the second Minnesota State Park, while the Wisconsin side was established in 1900 as the first Wisconsin State Park.

Deep pothole

Rock with several small potholes

Getting There

Waypoint: Latitude 43.3936727 N; Longitude 92.6709847 W
Street Address: US-8/St. Croix Trail and Milltown Rd., Taylors Falls, MN 55084


On I-35 north of the Twin Cities, take Exit 132 to Taylors Falls (US-8 East).  The entrance to the Park (Milltown Rd) is in Taylors Falls just west of the bridge to Wisconsin.  There is another part of the park in Wisconsin (hence the name Interstate State Park)

Pothole filled with debris