Monday, January 30, 2012

FOPOS Trails Committee Receives Award

If you've noticed that many of Princeton's open space trails have markedly improved in recent years, you can largely thank the remarkable efforts of the Friends of Princeton Open Space trails committee. Many a muddy stretch has been made passable with stepping stones and boardwalks, and many a mile has been cleared of wayward growth and fallen trees.

Last Wednesday, at a ceremony hosted by the Princeton Public Library, the volunteer group received a Leadership Award from Sustainable Princeton for their work. Left to right are Tim Patrick-Miller, Eric Tazelaar, Andrew Thornton, Clark Lennon and fearless leader, Ted Thomas.

Eric described the many locations where weekend workdays have made a difference.

Among other award recipients was another trail-related group, the Princeton Joint Pedestrian and Bicycle Advisory Committee, led by Janet Heroux, partly in recognition of their "sharrows" initiative.

Sunday, January 29, 2012

Sunrise Over Chores Undone

A couple early mornings ago, I noticed that the white translucent window shade had turned pink. Could this mean there was an inspirational sunrise-over-suburbia going on? I grabbed my camera and dashed outside in time to capture this ode to backyard neglect with the working title "Sunrise Over A Pile of Woodchips I Haven't Gotten Around To Spreading Yet." Note that reality is nicely framed by the optimistic words "Sunrise" and "Yet".

Hummingbird Notes

The Princeton Environmental Film Festival is concentrated this year into three 4-day weekends, of which this is the first. Saturday afternoon included a showing of "Hummingbirds: Magic in the Air", which uses cameras with 500 frames per second to show their singular hovering skills in slow motion. After the movie came a fascinating lecture by Charles Leck, a retired Rutgers professor. Here are some notes:

  • New Jersey's Ruby-Throated hummingbirds enter NJ each spring at the southern tip, returning from winter habitat in Central America. They migrate across the Gulf, flying about 8 feet above the water at 50 mph. Charles described sitting on the beach at the right time of year, watching as they'd come flying in off the ocean at the rate of about one every couple minutes. 
  • For the 500 mile non-stop flight across the water, they first build up their body weight, then may lose a third of it during the flight. They store nectar in their bodies as a fat that, when metabolized for energy, becomes water that in turn keeps them sufficiently hydrated during the flight.
  • During the day they maintain a body temperature around 105 degrees. Any higher and proteins would start to denature. At night, they ramp their supercharged metabolism down to 55 degrees. (The movie shows this transformation by using infrared cameras that register heat as read and coolness as blue.)
  • Charles mentioned the marsh at Rogers Refuge in Princeton as the best place to see the male hummingbird mating flight, on May 7 or 8. Stop by on those dates and there will likely be other birders to show you where to look.
  • Since hummingbirds cannot live on nectar alone, they have to catch insects with their skinny beaks to get protein.  Sometimes it's easier for them to rob spider webs.
  • The Lecks often lead walks sponsored by Washington Crossing Audubon or the Trenton Marsh.
There's much more information at

Saturday, January 21, 2012

The Second Snow

Snow finally arrived last night, having been loathe to return ever since its much criticized, heavy footed miscue back in October. My daughter, deciding the snow was insufficient for sledding, chose instead to send her little people on an exhilarating slide off the rooftop, aided by a broom handle.
Later on, some paddleboating in snow? What were they thinking? At least it got them outdoors.

This seemed much more sensible--some restful cloudbathing after their brief but exciting sledding venture, and a bit of stretching. Many a time have I thought there should be a designated "Conspicuous Stretching Zone" in the park, where parents wishing to spend their time more productively could feel permitted to assume various self-improving poses, free of any sense of awkwardness.

I didn't see how this contraption fit into the narrative. There was no enemy castle in sight, into which to hurl plague-infested pigs. Perhaps they thought it would be a good way to get back to the second floor.
As the day's light faded, a couple hardy northerners, dreaming of winters past, looked longingly out across the lake, wondering when the ice will be thick enough to skate on.

Tuesday, January 17, 2012

Nature Stereotype Listing Badly

In part to lure an audience, television tends to emphasize the violent side of nature. Preferential exposure is given to storms, wildfires and animals with big teeth. When nature is consistently portrayed as an adversary, people may forget that its primary role is as an ally, and that it's up to us whether we want to work with its forces or against them.

The latest contribution to the stereotype of nature as adversary is an ad seen last week immediately following the Miss America contest. We had finally strayed from Ingrid Bergman's improbable romance with Anthony Perkins in "Goodbye, Again" just in time to see Miss Wisconsin crowned the new Miss America, which closed with an ad for Carnival Cruises. They've launched a new ad campaign that compares land-based and sea-based vacations.

In the ad, a couple gazing serenely out at the ocean, drinks in hand, flash back to last year's camping vacation, when they were trapped in a car out in the woods by an enormous grizzly bear and mountain lion, pawing at the car, trying to get at the occupants. "Never again.", the woman says. Obviously, it's best to avoid the dangers of nature in favor of a safe, clean vacation on a massive cruise ship.

The ad segued immediately, improbably, into ABC evening news' lead story about the cruise ship that ran aground off the coast of Italy. Eleven found dead thus far, at least 24 missing. The ship is owned by a subsidiary of Carnival Corporation. April 15 will be the 100th anniversary of the Titanic's demise. Not a great time to be touting cruises as safer than a camping trip.

Friday, January 13, 2012

Backyard Bird Numbers Down?

I'm hearing reports from friends that their backyard birdfeeders are not needing as frequent refills as in past years, meaning there are fewer birds around. Though we don't have a birdfeeder, I noticed a flurry of bird activity in the backyard in early to mid-December, with mixed groups of birds visiting and then moving on, but have seen almost none since then.

This from Bill Sachs of Princeton:

In winters past, we have had to replenish the seed in our backyard birdfeeder at least twice a week.  This winter, the birds seem  noticeable by their absence and the interval between needed refills has exceeded two weeks!  Oh, we have birds visiting the feeder from time-to-time, especially mourning doves and blue jays, but visits by chickadees, titmice, nuthatches and wood peckers seem much reduced.  I am curious because there was a review article in a recent edition of Science magazine on “Globalization, Land Use, and the Invasion of West Nile Virus” (A. M. Kilpatrick, Science, 334: 323-327) in which the author writes,

“The impacts of WNV on wildlife have been yet more severe than those on humans.  Millions of birds have died from WNV infection, and regional-scale population declines of >50% have been observed for several species (11).  The range of taxa that have suffered declines is surprisingly large and includes corvids, chickadees and titmice, wrens, and thrushes (Fig. 1) and probably others.  Some populations have recovered after initial declines, whereas others have not.”

And this from an avid birder in town:

We too have had fewer birds at our feeder. Don't know why. Maybe mild weather, more berries, more insects? We've had a lot of Red-Tailed Hawks in the neighborhood, too. Declines of migratory birds, e.g., thrushes, have been occurring over a few decades, and that's due to multiple factors, including loss of winter habitat in the tropics. Among the year-round residents, or short distance migrants, disease could be a factor. Blue Jays were victims a while back, but seem to have recovered. House Finches, on the other hand, were decimated by disease a few years ago and have not come back.

Note: Ran into Henry Horn, professor emeritus at the PU Dept. of Ecology and Evolutionary Biology, who agrees that birds are very scarce. Closer to usual numbers are bluejays, crows and Carolina wrens. 

Note #2: Data from the Princeton Christmas Bird Count, and also from the national Cornell Backyard Feeder Watch, will be available soon. I'll post that when it comes in.

Saturday, January 07, 2012

Puerto Rico and Princeton--Parallels in a Rainforest

Even in a tropical rainforest, witnessed during a hike up El Yunque, it's possible to find parallels to Princeton's nature. El Yunque rises into the clouds 40 minutes southeast of San Juan, its slopes populated by a mix of palms and hardwoods. The Puerto Rican coqui frogs sing "ko-kee" along the path to the top.
With only the diminutive ferns of temperate forests as a reference, one has to get used to the concept of looking upward at a 30 foot high tree fern reaching into the clouds.
As in Princeton, nettles are found near streams,

Since jewel weed (Impatiens capensis) is a frequent companion of nettle in Princeton's floodplains, it wasn't surprising to find an Impatiens species growing along the trails in a Puerto Rican rainforest,

doing a good imitation of the Impatiens planted as annuals in northern gardens.

The Impatiens in El Yunque have the same spring-loaded mechanism for distributing seeds as our jewelweed.

The mountain, with its opulent vegetation providing abundant surface area for water to cling to, acts like a sponge to capture rainfall and slowly release it into the surrounding lands below. Though it was recommended to take rain gear, we found that weather changed constantly during the day. If a light rain started, we needed only wait five minutes for some other weather to come along. I speculated, purely for the sake of speculation, that such mild, free-flowing, constantly transitioning weather would influence people to hold less tightly to moods.

It was a surprise, in such an exotic world, to find information about two familiar birds. This sign tells of spectacular mating flights to be seen above the rainforest cainopy by redtailed and broadwinged hawks.
When I travel to other parts of America, I look for parallels to two species shot to extinction in the early 1900s in North America--the Carolina parakeet and the passenger pigeon. Puerto Rico's one remaining native parrot, which may share little relation to the Carolina parakeet other than family and color, still survives in small numbers in El Yunque National Forest.

Tuesday, January 03, 2012

Puerto Rico: Stalking the Elusive Baby Pigeon

While visiting Old San Juan, the question may come up: What to do while the next generation is feeding pigeons in the park? Break into a rendition of Mary Poppins' Feed the Birds in espanol?
Or take a photo of a hibiscus tree,
or a colorful caterpillar feasting on a favored plant?
Finally, my mission of the moment came into focus. I remembered a segment from a radio program years back called "Ask Dr. Science (He Knows More Than You Do!)", in which Dr. Science explained why we never see baby pigeons. I forget what the answer was--something about the species' deeply engrained embarrassment over the appearance of its young. This wall of nests seemed the perfect opportunity to finally get a glimpse. Yet even here, the babies were kept so well hidden that the enigma remains, at least until you google "baby pigeons" and click on images.

Monday, January 02, 2012

Puerto Rico: Skinless Trees and People

On the way to the historic fort El Morro, in Old San Juan, we encountered something that looked less like a tree than a sculpture built of rebar.
This branch is reminiscent of a man's arm without the skin, or an exagerated version of one of Princeton's musclewood trees (Carpinus caroliniana).
This sort of growth is common in more tropical climes, particularly among species of fig (Ficus). If you google images for strangler fig, you'll see all sorts of extravagant examples.
As explained in a Wikipedia entry, a strangler fig can actually begin its life above ground, sprouting on the limb of another tree, then extend its roots down towards the ground while also sending branches and trunk upward. Over time, the original tree dies off and the strangler fig completely usurps the space.

Some of our invasive vine species in New Jersey, such as English ivy, can weaken their host tree, but they don't develop the sturdy infrastructure to continue to stand if the original tree dies.

By chance, there was an exhibition called Body Worlds just down the street in San Juan,
featuring skinless renderings of people. As a friend once said after seeing pictures of her vocal cords, there's a good reason why people have skin.

And at a local museum, a similarly fibrous merging of tree and human. It's tempting to think the painting was inspired by the local strangler figs.

Sunday, January 01, 2012

Puerto Rico and Princeton--Buttress Roots

One of the pleasures of an acquaintance with plants is being able to see similarities and differences in distant plant worlds. Some of our potted plants, such as the pothos vine and various kinds of fig trees that show little ambition while standing neglected in a dimly lit corner, grow to enormous size outdoors in tropical climes.

The roots of fig trees can be as impressive as their canopies.
Here's one, growing next to dormitories at the University of Puerto Rico, that brings back memories of flying buttresses on European cathedrals.

If this tree were to ever blow over, which is looking very unlikely, it would take the wall with it.
Princeton offers a few examples of root buttressing. This white oak grows on a lower slope of the Princeton Ridge, in Herrontown Woods, where the soil is often wet for long periods.