The Moth Invasion of `07


Gypsy Moth Lymantria dispar

It’s particularly bad this year. At least I don’t remember noticing the large swathes of mountainside that were nearly absent of any green. While the gypsy moth caterpillar can be a real boon to birds such as cuckoos which feast on the insects, they can also cause tremendous damage to their hosts which include oaks and aspen.

According to Donald Eggen, director of the Office of Forest Pest Management for the Pennsylvania Bureau of Forestry, “Nearly 700,000 acres of Pennsylvania forests- primarily in the Poconos and central Pennsylvania- were defoliated last year because of the persistent bugs, and the infestation could be worse in 2007.”

Originally introduced accidentally around Boston in 1869, the first outbreaks began around 10 years later and it 1890 the first attempts were made to eradicate the moths. Unfortunately they were not successful and the moths still are causing problems over 100 years later. Below is the projected spread of the moths if their range continues expanding at the present rate of 21 km/year.

The effects of the gypsy moths could very well mean that only the less susceptible tree species will dominate the forest and some ecologically and economically important trees such as oaks will be lost.

Over the last 100 years over 20 insect parasitoids and predators from Europe and Asia were introduced to help control the moths with limited success. Birds feed on the insects but apparently not in quantities that affect the moths populations. More recently a virus and as well as a fungus have had good success in limiting the outbreaks. Unfortunately this year spring came so late that the fungus did not have time to have its effect before the caterpillars hatched and that is why there is a larger outbreak this year.

Moth outbreaks are currently also being controlled by direct spraying in areas that are hit under a joint program of state governments and the USDA Forest Service. If you are witnessing an outbreak on your property you should contact your extension service for more information on programs in your area.

Sources:

WBOC-TV- Gypsy Moths Leaving Their Marks on Mid-Atlantic Forests
USDA Forest Service- Gypsy Moth in North America

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The aberrant warbler and a firethroat


Yellow-breasted Chat © 2007 Drew Weber

Point counts have been good as of late. I was in Lancaster County a few days finishing up points in that area and my best find was a very outgoing chat. I had it singing during a point count near Muddy Run Reservoir so I marked the spot on my GPS and returned after my morning counts were finished. I only had to play a few phrases of its song on my car speakers before he popped up again, flying back and forth checking out who was trying to take his picture. Most shots I took were pretty bad but he landed on a utility tower long enough for me to fire off one shot and that is what you see. I had forgotten how fantastically goofy these warblers/tanagers look when doing their display flight. They have always reminded me of clowns.

I believe that chats are going to be separated from the New World warblers (Parulidae) fairly soon. I can’t remember the exact details but I think they will get their own family and be considered the evolutionary bridge between tanagers and warblers. Someone please correct me if my facts are way off.


Blackburnian Warbler © 2007 Drew Weber

In another lucky catch, I managed to photograph this brilliant male Blackburnian Warbler through my binoculars. This is not a method I have ever had much success with, and although its not a print worthy photo, and a little drabber than real life, I believe it captures some of the brilliance of the reddish orange throat these warblers flaunt. Blackburnian Warblers have a ridiculously high-pitched ending to their song and are one of the first to disappear as one’s ears lose those higher pitches. It makes me curious whether even with my good hearing I am missing parts of the song.


Tiger Swallowtail Butterflies © 2007 Drew Weber

At the same place where the Blackburnian was singing, there was a large congregation of 30-40 butterflies all in one clump. If anyone know what they were doing please leave a comment…

The Thrill of the Trill: Capturing an Insect Symphony

In the mornings, as I am zipping from point count to point count, I generally have the radio tuned to National Public Radio if I can get reception. A few days ago I was pleasantly surprised when I turned on the radio and out of the speakers buzzed the loud drone of the 17-year Cicada. Because I had just received the The Songs of Insects by Lang Elliott and Wil Hershberger from Amy over at WildBird on the Fly, I immediately recognized the sound and got very excited about hearing the interview. Unfortunately it was almost over and I didn’t have enough time between the point counts to listen to the rest, so I looked it up on NPR and found the page. It’s a great interview and I would recommend listening to it.

I would also recommend buying the book by clicking on the cover image, it is beautiful and full color, giving 2 pages to each of 77 species of crickets, katydids, grasshoppers as well as an accompaniment CD with recordings of each insect. I was really struck by the large, high quality photographs of each species that is featured on each page and the helpful description of the songs. You can learn little tidbits such as how to tell the temperature just by listening to the Snowy Tree Cricket, or which insect can set off a car alarm with its loud song. This is yet another of Lang Elliott’s amazing resources for finding out about more of the world around us, focusing on sounds.

And many thanks to Amy for giving me this terrific book.

Listing in PA and the run to see the AWPE

To start off with, I want to say that my Pennsylvania list is not really that impressive. Yet. I have been making great strides now that I have been spending more time in PA. I believe I was at around 240 about this time last year, and I am currently sitting at 257, with about 13 that I should be able to see with just a little bit of luck and a whole lot of stuff that will require a little bit more than luck.

To make it easier on myself, I have created a spreadsheet with all the birds that I would very much like to see in Pennsylvania. My biggest holes are waterbirds, sea ducks and shorebirds. I am missing both bitterns, maybe seven species of shorebirds and 2 of the scoters. Some of these birds just require visiting the Conejohela Flats with a little more regularity in the fall. Other species I want to see will require the perfectly aligned tropical storm to sweep out of the Atlantic and blow some storm-petrels, shearwaters, or terns my way. One, Whip-poor-will, only requires that I can drag myself out of bed before my bird surveys start (5am) to listen in some good habitat.

The one enjoyable thing about state listing is that it adds more excitement to seeing birds that are strays and vagrants from other parts of the country. I may have seen 50 Lazuli Buntings in the Dakotas and Montana, but seeing one in Pennsylvania was somehow even more special.

A bird I just recently added to my list for PA is American White Pelican. One individual was spotted a few days ago along the Susquehanna River north of Harrisburg. When it was relocated the next morning, I received a phone call that I should come and see it. At this time it was sitting calmly in the way, providing distant looks. I immediately started the 40 min drive to the river. Not more than 5 minutes into my drive I got a call that the pelican was taking off, circling up in a thermal and giving every impression that it was going to keep going up and leave. Well, I decided I might as well head to the river anyway and see what was there. I continued driving and a little later I received another phone call, this time telling me that it was still in the air, hurry! I picked up the pace a little once I was on a major route and had almost reached the rendezvous point when I got another call telling me to turn around, it was now south of their. I whipped my little car around and started heading south, pulling off the side of the busy 322 as Tom frantically pointed up at the circling bird. I leaped out and got to watch it for maybe ten minutes as it lazily circled up and down the river and finally disappeared from view. The pelican had been in the air for almost an hour total, an amazingly long time. I had really lucked out.

An excellent shot is available at Tom’s photo site.

The newest I and the Bird

Edition #50 of i and the bird has arrived at A Blog Around the Clock, a science blog run by a guy who goes by the screen name Coturnix. Give a read for the lastest in bird blogs.

Numero 51 will be hosted by The Birdchaser so send in your submissions to Rob (birdchaser AT hotmail DOT com) by Tuesday, June 12.