Thursday, August 25, 2011

Appreciating Hummingbirds in Illinois

Appreciating Hummingbirds in Illinois

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More often than not, when I try to point out hummingbirds to my wife and children, I wind up gesturing toward air. “Hey, guys,” I call, “come see the hummingbird at the . . . oh, never mind.”

That said, the months of August and September provide some of the year’s best opportunities for observing hummingbirds in Illinois. That’s because individuals that have been farther north during the breeding season collect here on their way south.

When I say, “hummingbird,” here I mean “ruby-throated hummingbird,” which is the only species from this family of birds that breeds east of the Mississippi, and the only one commonly seen in Illinois.

All ruby-throats are an iridescent green on the back, and whitish in front, with only adult males sporting the ruby red throat that gives the species its name.

Hummingbirds are perhaps most remarkable for how small they are compared to other birds. Ruby throats are shorter than 4 inches from bill to tail tip, and weigh just three and a half grams. That’s comparable to three and a half grapes, or about midway between the weights of a penny and a nickel.

Despite their small size, many hummingbirds migrate over long distances. Ruby throats heading south may travel 2000 miles to reach their winter territory in southern Mexico and Central America, including a 500-mile nonstop leg of the trip over the Gulf of Mexico.

Hummingbirds are also remarkable for their agility in flight. With wings that beat 53 times a second, they can hold themselves perfectly still in front of a flower, then zip off in any direction—up, down, sideways, or even backwards.

Most people are aware that hummingbirds feed on nectar, which they obtain with their elongated bills. But nectar represents only half of the ruby throat’s diet. The other half is insects. Ruby throats most often catch bugs by “hawking” them, which is to say they wait on an open perch for prey to come by then fly out to grab it from the air. Ruby throats also pick insects and spiders off of trees and flowers, a behavior known as “gleaning.”

People who observe hummingbirds are often struck by how combative they are, despite their delicate appearance. Even where there are multiple sources of food and plenty of perches, hummingbirds chase each other off like lions at a kill.

The easiest way to attract hummingbirds to your yard is to provide food for them. In the long term, you can do this by planting native perennials such as columbine and bee balm, or, better still, trumpet vine, which is a hummingbird favorite with its 3-inch long scarlet flowers. For a quicker fix you can simply put up a hummingbird feeder filled with either commercial imitation nectar or a 20-percent solution of sugar water, for which recipes are widely available in birding books and on the world wide web. [For directions at Hummingbirds Forever click here.

Thursday, August 18, 2011

An update on efforts to promote cycling on and around U of I campus

An update on efforts to promote cycling on and around U of I campus

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As the University of Illinois again bustles with students, I thought it would be a good time to look over efforts to facilitate bicycling on campus. Toward that end, I spoke recently with Morgan Johnston, who is both Sustainability Coordinator and Transportation Demand Management Coordinator with Facilities & Services.

Johnston was happy to announce the completion of a Campus Bicycle Plan to be released soon, which was crafted by a task force that included representatives from the cities of Champaign and Urbana, the C-U Mass Transit District and the Champaign County Regional Planning Commission. I should add that among all of the people and entities associated with local efforts to promote bicycling, Johnston called attention to the citizen group, The aim of the plan is to bring cycling infrastructure on campus up to current national standards.

Johnston emphasized that while the plan is important for connecting campus efforts with efforts that have been developing in Urbana and Champaign in recent years, much has already been accomplished in the University District.

For example, Illinois Street has become a heavily preferred route for cycling between Urbana and central campus, thanks to the traffic light that facilitates crossing Lincoln Avenue, and the on-street bike lanes that run from that intersection to Goodwin.

Goodwin Avenue itself has been converted into what planners term a “complete street,” which means it was reconfigured to better accommodate not just cars, but all users. In this particular case that means the addition of curb bump-outs to reduce the crossing distance for pedestrians at intersections; enhanced stops for the loading and unloading of mass transit buses; and dedicated on-street bike lanes for cyclists.

Similar changes are currently nearing completion on Fourth Street in Champaign.

In addition to pointing out changes in infrastructure, Johnston reminded me that the Campus Bike Project is now in its second year of operation. Located in garage space provided by the Prairie Research Institute and operated with funding from the Student Sustainability Committee and Facilities & Services, the Campus Bike Project is a nonprofit, membership-based repair space. It’s a place where students, faculty and staff who join can drop by to do all sorts of work on their bikes, from putting air in the tires to a complete overhaul. The Campus Bike Project also sells refurbished bikes (which come with a one-year membership), and offers a build-a-bike program, which allows members to create their own ride from a salvaged bike at very little cost.

The Student Sustainability Committee has also funded the purchase of two permanent kiosks for bike repairs to be installed on campus, one to be located near the Illini Union, and the other near the Campus Bike Project. These ingenious repair stands, called “Fixits,” provide easy access to an air pump and the basic tools needed to keep bikes rolling 24-7.

Anyone who has searched in vain for an open spot to lock a bike on campus will be interested to know that more bike parking is on the horizon. A survey was conducted last May to help determine where the needs are most critical, and the Student Sustainability Committee has provided funding for design. Installation of the first new parking stands associated with this effort will begin at the Law Building within the next month.

Thursday, August 11, 2011

Thirteen-lined ground squirrels (not chipmunks, not gophers)

Thirteen-lined ground squirrels (not chipmunks, not gophers)

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My encounters with ground squirrels in the west this summer reminded there’s a common, yet fascinating animal closer to home I’ve been meaning to profile, the thirteen-lined ground squirrel. Do you know the one I mean?

If you’ve had a small squirrel dash in front of you as you drove on a country road bordered by crops, or you’ve seen a chipmunk-looking critter darting about in a cemetery, you’ve probably encountered a thirteen-lined ground squirrel. Some people call thirteen-liners gophers because they live in the ground, but in scientific terms, they’re members of the squirrel family.

Thirteen-lined ground squirrels are among those animals that have benefited from human development because they thrive in the close-cropped landscapes we create, from roadsides and pastures, to cemeteries, golf courses, parks and other lawns. Their geographic range, which encompasses much of the central U.S. and Canada, has actually expanded over the past two centuries.

If you were to draw a thirteen-lined ground squirrel based on its name, you would produce a picture that left out a notable characteristic of the original. Yes, they are marked by about thirteen alternating stripes of dark brown and light tan fur that run from neck to tail. But what’s equally striking is that the wider, dark lines are decorated along their entire length with evenly spaced light dots, giving them a star-spangled appearance. There’s a golden tinge to some of the lighter fur on thirteen-liners, and they’re the creature on which the University of Minnesota’s Golden Gopher mascot is based.

Thirteen-lined ground squirrels eat just about anything they can get their little paws on, from insects of all sorts to the occasional small vertebrate (including carrion), to grasses, flowers, seeds and crops. They have pouches in their cheeks that they use to transport food to their burrows for eating later. (If you have trouble with thirteen-lined ground squirrels eating from your garden, University of Illinois Extension’s “Living with Wildlife” Website provides suggestions for dealing with them:

Thirteen-lined ground squirrels are, in turn, food for a wide range of other animals, including coyotes, foxes, weasels, dogs, cats, hawks, owls and snakes.

One way thirteen-liners avoid being eaten is by excavating short, shallow escape burrows throughout their territories, so they’re never far from a hole to dive into. They also create deeper, longer burrows for nesting and hibernating.

And thirteen-lined ground squirrels hibernate like champions. After fattening up in the Fall, they retreat to a chamber that’s below the frost line, plug the entrance with soil, and curl up for about four months. During hibernation—which begins in late October or early November and lasts until late March or April—their body temperature nearly matches the temperature of the burrow, dropping as low as 37 degrees F. By the time thirteen-liners awaken, they have lost up to half of their body mass.

During the months thirteen-lined ground squirrels are active, you need not get up early to see them, nor do you need to brave inclement weather. They are most active on warm, sunny days, and they don’t even bother coming out of their burrows in the rain.

To learn more about thirteen-lined ground squirrels, or any of the other mammals you might see when you’re out and about in the Prairie State, let me refer you to the source for much of the information in today’s commentary, the Field Manual of Illinois Mammals by Joyce E. Hofmann. It’s published by and available through the Illinois Natural History Survey, which is a division of the Prairie Research Institute at the U of I in Champaign.

Thursday, August 04, 2011

Freshwater mussels: overlooked, under appreciated residents of Illinois streams

Freshwater mussels: overlooked, under appreciated residents of Illinois streams

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If you’ve spent time canoeing or kayaking on rivers in the Midwest, you’ve probably come across the shells of freshwater mussels from time to time. On the outside, mussel shells are seldom pretty, but the pearly shine of the interior surfaces often prompts people to pick them up.

Scientists distinguish among different species of mussels by focusing on the shape of certain parts of the shell. Here, for example, is how the Field Guide to Freshwater Mussels of the Midwest (Illinois Natural History Survey: click here to see free online version) describes the appearance of a species that goes by the scientific name Quadrula quadrula: “Shell quadrate to rounded, and somewhat inflated. Anterior end rounded, posterior end squared or truncated.”

Now, if that doesn’t bring to mind a very clear picture for you, try the common name for the same species: it’s “mapleleaf.” [Photo of Quadrula quadrula by Kevin Cummings, from the field guide. It reminds me of a maple leaf, anyway.]

Other Illinois mussels carry similarly evocative common names, which tell both what the creatures look like and what objects were familiar to the people who named them. Among them some of my favorites are washboard, pistolgrip, wartyback, heelsplitter, deertoe, spectaclecase, and pocketbook.

According to Kevin Cummings, a mussel expert at the Illinois Natural History Survey on the U of I campus, North America is home to a greater diversity of freshwater mussels than any other continent, with nearly three hundred species and subspecies. Some eighty of these are or were once found in Illinois. Many mussels have become locally extinct in former habitats, and only about forty species are regularly found in the state now.

Freshwater mussels live a low-key life for the most part. They pass their days hunkered down in the sand or gravel, usually in flowing water. They feed on microscopic plant and animal life, as well as other tiny bits of organic matter, which they filter from water they take in through one siphon and eject from another. Mussels are fed upon by a variety of fish and birds, as well as muskrats, otters, and minks. Minks leave the cleaned shells of mussels they’ve eaten in a pile near the water’s edge called a midden, which can be a great place to find and identify shells.

The early development of mussels is a bit more complex and dramatic. Mussel eggs are fertilized within the female, with sperm that has been released into the water by nearby males. Inside the female, the fertilized eggs develop into larvae, which scientists call “glochidia.” To grow further, these glochidia must be expelled and attach themselves to the gills or fins of a fish for some weeks, where they will take on their adult form, in miniature, before dropping off to live at the bottom of the stream again. By sending forth their young attached to fish, mussels are able to disperse much farther than they would under their own power.

Over time, freshwater mussels have served a variety of human purposes. Native Americans ate their flesh and used their shells for utensils, tools, and jewelry. During the nineteenth and early twentieth centuries—before the advent of plastics—mussel shells were used on an industrial scale to make buttons. Since the 1950s, mussel shells have been exploited commercially for use in the production of cultured pearls in Japan.

It is unfortunate for mussels that they are not more cute and cuddly, because as a group they are among our most endangered animals, suffering from overexploitation, the pollution and physical degradation of waterways, and the introduction of exotic species to their habitats. Perhaps our best hope for preserving them comes from the growing awareness that the health of our rivers and streams is really a component of our own health.