Tuesday, December 30, 2014

Back from holiday in Carlsbad, NM!

On the way to Carlsbad Caverns
I've recently returned from holiday in Carlsbad, NM.  Averaging a little under 13 inches of rain annually, this region is where the the Chihuahuan Desert takes over after the last gasp of the short grass prairie fades in far eastern New Mexico. My main impression was of a thinly grassed chaparral dotted with spiky yucca-like plants I couldn't tell apart. Remarkably, it rained or snowed two of the three days I was there. This was some feat considering the area averages only 41 days of precipitation per year. I have a knack for getting rained on in deserts.

Closer view of the vegetation
I'm not totally clear on differentiating the various spiked rosettes that dominated my visual impression of the landscape. I do not think I could tell them apart without their dried floral stalks. Thanks to guidebooks, I know I saw sotol (Dasylirion leiophyllum), torrey's yucca (Yucca torreyi), mescal agave (Agave parryi), and lechuguilla (Agave lechuguilla).

I've gleaned the following: sotol and lechuguilla's leaves have hooks curved back toward the base, but sotol leaves are finer with dried, light brown fibers extending far beyond the tips of their leaves. Mescal agave looks like what we call a 'century plant' in horticulture, and torrey's yucca is raised up on a brown pedestal of its previous growth, leading me to initially call it a 'joshua tree'. Yuccas (vs. agaves and sotol) don't seem to have hooks on their leaf edges. Of course, most people go to Carlsbad to see what's underground, not to do a comparative study of spiny rosettiform succulents.

Possibly a torrey's yucca?
A giant fungus-like speleothem
One of the stories my dad tells about me is that as a small child I essentially had a 'freak out' in Luray Caverns, VA. I remember reading some Tom Sawyer-y/Little House on the Prairie-type book about children getting lost in the caverns at about that time. I imagine I was pretty concerned about the lights staying on and getting back to the surface. Supposedly we completed the tour but I begged and whined the entire time.

This family story of some early childhood cave-associated terror came to mind as I prepared to go down into the cavern. I hadn't toured a cave system since that experience, so I was curious if I would discover some forgotten fear. I am pleased to report that I enjoyed visiting the fantastic Carlsbad Caverns without incident. Some things do change.

The big room
Carlsbad Caverns is famous for its remarkable speleothems (cave formations including: stalactites, stalagmites, columns, etc). While most caves are formed by carbonic acid, the limestone of Carlsbad Caverns was dissolved by sulfuric acid.  The caverns started forming approximately 4 million years ago, and progress ceased with climate change at the end of the Ice Age. These caves might start building again, if climate changes bring the area more rain.

Despite the lull in geologic activity, you could hear dripping water echo through the caverns. It smelled like dust and wet stone. Human odors seemed sharper for some reason. Whenever I passed someone wearing cologne, it was stronger than at the the surface. I'm not sure if the human scents were being thrown into relief by the spareness of the cave, or they were more efficiently picked up by my nose because of the 90% humidity underground.

It is astonishing to me that early explorers dropped ladders in the abyss and descended into the darkness in total ignorance of what they would find. It seems likely that this need to have a finger in every pie is a characteristic human trait.

I saw more of New Mexico than the caverns, and I will write on that shortly. Until then: have a happy New Year's Eve!

Higher elevation desert slopes near visitor center

Thursday, December 11, 2014

Tracks

Skunk tracks in tuff? Badlands National Park
Winter is a good time to work on your tracking. I am not especially skilled. I can generally tell canid from feline, and anything with unexpectedly burly claws on a smallish paw could be a skunk or badger. Those rascals love to dig. I learned most of the little I know from a day long class with a biologist that I took when I was in grad school in North Carolina and the rest from books.

What struck me most was the diversity of wildlife you share a space with but never see. Many creatures are either active at night or are crepuscular, so you are unlikely to stumble upon them on your hike or jog. In the semi-rural piedmont of North Carolina where I took my class, we saw sign of river otters, mink, beavers, foxes, mice, rabbits, house cats, and coyotes. You can get a feel for the lushness of North Carolina's forests from that list.

Shortly afterwards I moved to Nebraska. My regular jogging route was up and down gravel roads. I'd pat the nose of the neighbor horse, and I flushed deer and turkey most mornings. I saw plenty of their tracks, but I also saw coyote, badger, skunk, and, in the western part of the state, antelope. My impression of Nebraska was that it was a sportsman's paradise. They are drowning in game. Between the resident turkey flock (one technical term is 'rafter'; as in 'a rafter of turkeys') and the jumping deer, Nebraska seemed veritably made of meat.

What happened here? Near Paria canyon, UT
Something long dead
(fossil dino tracks)
Tracks and sign can tell you more about a place than you might otherwise sense.  In Utah I saw the marks of desert beetles, lizards, and crows. I also saw the signs of long dead creatures. I was in Utah volunteering as a range technician's assistant, and one of our monitoring locations happened to be near a fossil bed. Dinosaur tracks preserved in ancient mud had been exposed at the surface by erosion.

I was shocked that these fossils didn't have so much as a fence around them. You could walk right up and touch them, or put your feet in the tracks and mimic the dinosaur's gait if so inclined. The location was self-guided, so there wasn't even anyone to stop you from taking a pickaxe to the rock and hauling away a chunk of dino-print. It seems that the people who have trekked out so far have managed to restrain themselves. Let's hope that continues to be the case.

People! Chipped toeholds near Paria Canyon, Utah
Also in Utah, I enjoyed seeing the signs of ancient peoples. These chipped 'toe paths' were pretty common. I took the above picture next to my campsite. These lines seem too perfect to have been caused by erosion, but I'm open to someone else's interpretation.

Raccoon tracks look like children's hand prints (Old Alton Bridge)
I must admit I haven't devoted much time to tracking since I got to Texas. I've been travelling so much for work I've neglected to take all the dreamed of road trips to the western part of the state, where the bare ground shows more evidence of passing creatures. I have seen a few mud prints in the parks around town. Raccoon and fox, nothing too exceptional, but pleasing to see all the same. Raccoon prints look for all the world like a baby pressed their hands into the dirt. Fox prints are smaller and less rectangular in composition than the average canine, but they have the permanently extended claws of their family. Canids leave claw marks in their tracks and cats don't because cats have retractable claws.

I hope to tour a little of the western part of the state over the holidays. I'll certainly takes pictures to document any interesting traces of the resident wildlife that I should come across!

Canid, probably red fox (Old Alton Bridge)







Saturday, December 6, 2014

Winter Ducks at the Drying Beds

How many can you spot?
I took my bird-dog bird watching at the Village Creek Drying Beds in Arlington, Texas this morning. This was not as fool hardy as it may sound. As I have mentioned in previous posts, Colby is something of an embarrassment to her line-- she prefers butterflies to coveys. She also knows that when I have my camera out tugging and general knuckle-headed-ness is futile. I will remain un-moved until I'm done. She seems to enjoy our excursions though, and I get a kick out of watching her try to figure out what's got my attention. This morning it was ducks.

The Village Creek Drying Beds are locally renowned as an excellent place to view ducks in the winter.  Or they were renowned, I should say.  The site is in the process of decommissioning. Originally used as a solid waste treatment facility, it is now the domain of birders, dog walkers, and nature photographers. Water levels are kept much lower than they used to be, and thus the numbers of visiting waterfowl have declined.  I only saw one bed with enough water to draw ducks when I visited.

A northern pintail
I was actually visiting the drying beds to work on my duck ID. I know basically nothing about ducks, and a warm winter day where most of the other wildlife has gone cryptic seems like as good an opportunity to learn as any. In addition to the ubiquitous mallards, I saw northern pintails, green winged teals, and northern shovelers. There were many other ducks drifting and dabbling with less obvious field markers. I had to look up the term "dabbling"-- this is the word for the duck feeding behavior where they go 'bottoms up'. Ducks are described as being dabblers or divers, where divers dunk themselves entirely and the dabblers do underwater headstands leaving their rear-ends visible above water.

Green winged teal
I think my favorites were the pintails, probably because they were the easiest to spot to my untrained eye. Pintails have… an elongated pin-tail. They also have a white breast and grey head. Green winged teals were easiest to identify based on the white slash ahead of their wing. Their copper heads seemed to make their green ear patch hard to spot at a distance. Northern shovelers were distinctive because of the strong white/chestnut patterning on their bodies and their dark heads.

Northern shovelers
The origins of the names 'pintail' and 'green-winged teal' are pretty obvious, but what about 'shoveler'? Do they use their bills to shovel and pick through mud? Well, not really. I suppose their bills vaguely resemble shovels, but the term most commonly used to describe them in the literature is "spatulate". Their bills are broader at the end than at the base, and the edges are toothed like a comb. They use these crenellations to filter food from the water. This species is remarkable in that it is common to North America, Europe, Africa, and parts of the Indian subcontinent.

Another picture of a shoveler 
Supposedly the Village Creek Drying Beds are even better during the spring and fall migrations. I imagine that its usefulness as a duck pond will ebb and flow with rainfall and chance as the drying beds are totally phased out. Until that happens, I can still recommend this spot as an excellent place to see ducks.

Dry drying beds

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Useful Links
visual guide to Texas ducks:
https://tpwd.texas.gov/publications/pwdpubs/media/pwd_bk_k0700_0517.pdf

list of ducks and relative commonness:
http://www.nctexasbirds.com/home/checklist/test-table

Bird World's map of birding hotspots:
https://www.google.com/maps/d/viewer?msa=0&mid=z9S4BN39WyME.kdjnnF6IFvJg

The description of Village Creek Drying Beds:
http://www.birdwatchingdaily.com/hotspots/45-village-creek-drying-beds-fort-worth-texas/

FW Audubon's list of hot spots:
http://www.fwas.org/index.php?pageid=birdingdfw