Thursday, September 23, 2010

Good-bye, ospreys! See you next year...

If you spend much time on the Virginia coast, the high-pitched call of the osprey is a familiar sound. In fact it’s so familiar that it’s often taken for granted …until it’s gone. I love fall with its cool sunny days and blue, blue skies, but I am always a little sad when the ospreys leave. Around mid- September, the ospreys who summer on the Chesapeake Bay disappear. Where do they go?

Dr. Richard O. Bierregaard, Jr. knows! He has been studying ospreys for over 40 years. In 2000, in collaboration with Dr. Mark Martell, he began installing GPS tracking devices on young ospreys to track their migration patterns, including several from the Chesapeake Bay region. Ospreys have been tracked to winter quarters in the Caribbean, Central and South America, as far south as Peru! His tagged birds have names and his website is updated regularly with their progress. By September 12, three birds, Penelope, Sr. Bones and Thatch (Thatch is from Delaware) had begun the long and perilous journey south. Gunny left on September 19 and arrived in Virginia Beach on Tuesday. Other tagged birds, including Neale, Sanford and North Fork Bob, should be leaving soon. To follow their progress, go to:  I have to admit that following these birds as they make their way south and, hopefully, back north again could become an addiction.

If they survive the journey and winter, they will return around mid-March to nest near the area where they were born. Ospreys begin mating at three years of age and will often mate for life. Nests consist of bulky piles of sticks on navigational markers, duck blinds, utility poles or high up in a pine tree, but always near the water. Females usually lay three eggs in mid-April to late May.  By July, the fledglings fly from the nest and begin to practice their steep dives to catch fish.

Ospreys are sometimes confused with bald eagles. It’s certainly easy to do – ospreys look remarkably similar to both juvenile and adult bald eagles. Here’s a brief primer to tell them apart: ospreys are dark brown or black with white underparts, a broad black eye stripe and a black patch on the underside of the wings. Adult bald eagles have white heads and tails but dark underparts, while juvenile bald eagles are all brown or mottled brown and white all over. Ospreys are slightly smaller than bald eagles and fly with their wings "crooked" in an M shape, whereas bald eagles fly with their wings in a flat line.

We are fortunate here in the Chesapeake Bay region to have the largest nesting population of ospreys in the world, over 2000 pairs which accounts for 25% of the US population. While they are wintering in warmer climes, I hope to follow the travels of Penelope, Sr. Bones, Thatch and Gunny and will eagerly await their return in the spring!

Tuesday, September 14, 2010

A Webworm Horror Story

Last Sunday I decided to enjoy the beautiful fall weather and eat my lunch outside. About halfway through my sandwich, I glanced up to see something fuzzy crawling down my bangs onto my nose – UGH! It was a fall webworm – you know, those nasty hairy caterpillars whose giant webs appear on tree branches every fall? There seems to be a bumper crop this year – caterpillars are crawling on everything: across yards, along sidewalks, up walls, on decks and porches… you get the picture. When I went outside to eat, I purposely positioned my chair away from the trees to avoid them (and to avoid the occasional falling walnut – ouch!). This fellow found me anyway and sort of put me off my lunch.

Description of Damage
In the grand scheme of things, fall webworms do not do a tremendous amount of permanent damage, although the webs are definitely unsightly. Caterpillars feed on leaves inside the webs, gradually enclosing more foliage as they grow. Heavy infestations may defoliate a tree but rarely kill it. Over 100 species of trees play host to these voracious pests, but here in central Virginia, they seem to prefer nut and fruit trees, such as walnut, pecan, cherry and crabapple.

Life cycle
The adult moth is snow white, often with dark spots, and somewhat hairy (not surprising, considering the caterpillar). They lay their eggs on the underside of leaves in May through July. The larvae hatch in about 2 weeks and immediately begin to spin webs and feed on leaves. Pupation occurs after 4 to 6 weeks of spinning and feeding and can usually be found in leaf litter or just below the surface of the soil. In the South, we are especially lucky - we get at least 2 generations per year!

Control is not necessary; however, you may not be able to tolerate the unsightly mess. If you do decide to take action, mechanical control is best. When you can reach them, prune branches containing webs and destroy them. Chemical control must be done when webs and larvae are small, no later than July, but it is not necessary. If you are lucky, birds and other natural predators may come to your yard and do the job for you!

Just remember – do not eat lunch under the webworm tree…