Signs of Spring Update: February 7, 2003

Today's Report Includes:

• A New Challenge--West Nile Virus: Challenge Question #4
• Current Happenings: Lots of Good News!
• Frozen Fruits: Discussion of Challenge Question #2
• Frozen Insects: Discussion of Challenge Question #3
• Please Report "Signs of Spring" from Your Part of the World

American Crows are extremely vulnerable to West Nile Virus. In laboratories, 90-100% of crows exposed to the virus die.

Most mosquito bites make people itchy, but don’t cause any other problems, at least in the United States and Canada. (Mosquito-borne diseases are a serious problem in tropical areas of the world.) But in 1999, a disease appeared in New York that had never before been seen in America, West Nile Virus. And ever since then, this disease has been spreading, killing birds, horses, some other animals, and humans. Birds have thick feathers to protect them, yet they get many bites. How can mosquitoes possibly bite them? Think about it, and then answer

Challenge Question #4:
"Where on a bird's body is it most likely to get mosquito bites?"

(To respond to this question, please follow the instructions below.)

How did the virus get here? How does it work? How are we fighting it? To learn more about West Nile Virus and what people are doing to protect humans and animals from it, see

• West Nile Virus: A New Challenge

These field notes all came from you and other Journey North participants. Remember to share your sightings of first frogs, earthworms, red-winged blackbirds, barn swallows, emerging leaves, flowing sap, melting ice and other spring events. You can report any of these things, plus read all the field notes of other participants, by pressing the "Owl Button" at the top of every Journey North page.

The oldest known Gray Jay. Photo by Tom Nicholls.

And here's an exciting discovery: a Gray Jay banded last August was just confirmed as being the oldest Gray Jay ever recorded! How old was the bird? Meet the Gray Jay and find out more about how scientists learn how old wild birds can live to be here:

• Current Headlines: Oldest Gray Jay

Frozen fruits are much harder than warmer ones. Kasey from Ms Deede's class notes that "robins might prefer the small berries than the larger chunks of fruits because they are smaller and softer and easier to swallow whole. This is important because they could choke if the berries are too large. Robins swallow the berries whole because they have no teeth to chew with."

Also, frozen fruit will chill a bird until it thaws in the bird's stomach. Frozen berries are easier to thaw out than big chunks of frozen apple.

Antifreeze may keep the tissues from freezing, but in frozen conditions, insect body temperatures are still very cold, making the insects very sluggish. And virtually all insect food is gone or difficult to get at in winter: there are no leaves on trees, and the dried, brown leaves on the ground have little nutritional value. Frozen plant tissues are too hard for insect mouth parts to chew. Some kinds of insects are active on warmish days, but overall, most insects just bide their time waiting for more pleasant days to come.

Report your "Signs of Spring" sightings to Journey North.

IMPORTANT: Answer only ONE question in each e-mail message.

1. Address an e-mail message to: jn-challenge-spring@learner.org
2. In the Subject Line of your message write: Challenge Question #4
3. In the body of your message, give your answer to the question above.

The Next Signs of Spring Update Will Be Posted on February 14, 2003.