Thursday, August 27, 2009

Flying Away

Summer is slowly slipping away as we approach the end of August. There are many signs of the season's end: Labor Day, Back-to-School sales, mums for sale/on display all over town, etc. One of the surest signs of summer's end for me is bird migration.

Many folks are aware of bird migration in the spring. Robins and bluebirds and others return from their wintering grounds and fill the air with song. Just as dramatic, though not so audible, is the end-of-summer migration.

It's still warm! Why are the birds beginning to leave so soon? Well, temperature actually has very little to do bird migration. Days are shortening and so are the food supplies that these birds rely on to sustain themselves and their young all during the spring and summer. For many migrants, they have a long trip ahead of them, and there's no good reason to delay departure until food sources run low or disappear.

For the hummingbirds, orioles, flycatchers, ospreys, and broad-winged hawks (just to name a few) traveling to Central and South America, the time is now. As they move south, they will stop over and forage in locations where food is still abundant. Eventually they will reach the wintering grounds in the southern hemisphere where summer's bounty is just beginning.

In honor of the beginning of this migration that will continue well into the fall and the beginning of winter, I've posted a few of my favorite photos of birds in flight from this past spring and summer. Enjoy them and then make your way outdoors to witness the miracle of bird migration for yourself.
Laughing Gull - photographed near Hilton Head, SC

Double-crested Cormorant - photographed at Ottawa National Wildlife Refuge, Ohio

Great Blue Heron - photographed at Westmoreland Sanctuary

Chimney Swift - photographed in Massillon, Ohio

Black Vulture - photographed near Hilton Head, SC

Turkey Vulture - photographed near Hilton Head, SC

Red-tailed Hawk - photographed near Hilton Head, SC

-Adam Zorn, Naturalist

Thursday, August 20, 2009

Naming our Turtles

Sorry for the delay. Now...back to blogging!
If you've taken a casual look around our museum's 1st floor lately, you probably noticed a recurring trend amoung the live animals. Many of them bear a surprising resemblance to turtles. In fact, almost half the live animal collection is a turtle. Clearly we have a soft spot for turtles of all types at the sanctuary. But the museum isn't the only place on the property to see these shelled reptiles.

Two of the most common species of turtle take up residence in the various ponds and lakes around the area. Painted turtles (like the one above) and snapping turtles are common sights in our Bechtel Lake. Since the early 1990's, Westmoreland has been monitoring the presence and abundance of painted and snapping turtles in Bechtel Lake and a small pond at the Wildlife Management Area.

Turtles are typically caught in a live trap placed in the water and baited with sardines or a leaky bottle of fish meal. Traps are checked periodically and any captured turtle is given a quick external examination for signs of trauma, parasites, or physical abnormalities. Each specimen is also measured and then marked by drilling or filing one of 24 marginal scutes. This harmless, yet permanent mark, allows each individual to be identified over time if captured again in the future.

Two weeks ago we removed four painted turtles from one of our traps in Bechtel Lake. Each individual went through the same procedure as described above, but now we've added an extra dimension to the project.
As you can see above, each turtle is getting a paint job to aid in the identification of individuals as we see them basking or swimming around the pond. Each turtle has a series of three letters on its back in white fingernail polish. Once dry, the polish is non-toxic and is of no harm to the turtle. When the scales of the turtle's shell are shed, the polish will come off too.

Here are our four recently marked turtles in Bechtel Lake:

SAM is a 5-1/4" male with a large diagnostic crack and dent on the right-side of his carapace.

LAR is a 4-1/4" male in good health. He had just a few leaches attached to the exterior of his plastron.

ASZ is a large female measuring 6-3/4". She had a number of leaches attached to her plastron which were removed before release.

SAR is a 4-1/4" male with minimal leaches attached to the plastron.

Each of these turtles were new captures. Now that each has an identity, we will be able to track their presence in Bechtel Lake. Interestingly, we have yet to recapture turtles previously marked that have been released in the lake. Have they moved out? Are they still there, but wise enough to avoid the traps? With this project we should be able to gather enough data to answer these and other questions about the turtle population in Bechtel Lake.

If you see one of the above turtles or similarly marked turtles around the sanctuary, please let us know when and where your observation was made. Your observations can be recorded in the Wildlife Sightings box at the Easy Loop trailhead, on the clipboard in the kiosk near the parking lot, or e-mail us your observation (find our address by visiting our website).

-Adam Zorn, Naturalist