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Signs of Spring Update: April 4, 2003
Today's Report Includes:
- Get Ready for Wrens! Link to Activity
- Learning about Wrens: Link to Lesson
- Fun with Wrens: Challenge Question #16
- Current Happenings: Big April Fool's Day Excitement!
- More about Aquatic Insects: Discussion of Challenge Question #15
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Some of our favorite signs of spring, like robins and the first frogs, appear while the snow is still flying. But one of the most cheerful signs of spring waits until it really IS spring. House Wrens feed on crawling, hopping, and flying insects. Their bodies are tiny--they weigh less than two nickels--and since they're warm-blooded, they must have enough food to maintain their body temperature. So they can't risk arriving in the north before they are guaranteed of enough insects to eat.
House Wrens haven't arrived in many North American places yet. Even if you can't go out and look or listen for them yet, you can plan for their arrival by building and setting out wren houses.
Learning about Wrens
Wrens are tiny and drab, but when they're around, they're easy to find--because they sing loud and clear. House Wrens are found throughout much of the US and southern Canada. They are likely to sing just about anywhere. Winter Wrens can be found in all but the extreme north during migration, but virtually never sing until they reach their breeding grounds. Carolina Wrens are usually found only in the southeastern states, but their loud, cheerful song can also be heard in the background of a lot of movies and TV shows. To learn about wrens and to hear their songs, see
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| Carolina Wren at Feeder |
Journey North's own Elizabeth Howard had a lot of fun videotaping the wrens in her yard, and making observations which she recorded in her field notebook. Watch the videos here:
For being such tiny birds, wrens are inquisitive and feisty, and make fascinating subjects for study. If you know of a birdhouse or feeder with wrens coming regularly, you can do some interesting research projects on them.
One day Elizabeth watched her wrens for 30 minutes, and recorded the time in her field notebook whenever one of the parents returned with food. Study her data here:Then put on your thinking cap and see if you can answer this question:
Challenge Question #16:
"What are two different reasons why the number of feeding trips increases sharply when the babies are about a week old?"
(To respond to this question, please follow the instructions below.)
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Great Blue
Herons and Osprey return when fish become available. Photos by Stephen
J. Lang for The Wisconsin
Society for Ornithology |
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This week of April Fools Day brought lots of exciting news! If you haven't heard, the ice went out April 2 on Walden Pond and the ultralight-led Whooping Crane chicks in Florida began the spring migration all by themselves on April 1! On April 1, Susie Ruby at the Redbud Valley Nature Preserve in Catoosa, Oklahoma, saw her "first Red Admiral butterfly on a warm, windy morning. It was nectaring on tree sap with Mourning Cloaks, Goatweed Leafwing, and Question Mark butterflies." Elizabeth Howard saw her first Great Blue Heron of the year on April 2 in Charlotte, Vermont, and the FedEx man in her neighborhood saw one the day before. David Cummings saw his first Osprey of the year at its nest on a railroad bridge over Henry's Fork on the Snake River in St. Anthony, Idaho, on April 1. Spring is here--time to cheer! Be sure to check out the newly updated Red-winged Blackbird map!
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Eastern Phoebe feeding
on insects on an algae mat. Photo by Brian Boldt |
As ice goes out, sometimes goopy algae covers areas of some shorelines. Some kinds of algae are evidence of certain kinds of pollution, but algae can also be part of a healthy lake's natural ecosystem. In Milwaukee, Wisconsin, on the last weekend of March, Brian Boldt reported, "Cladophora algae seems to be a haven for insect larvae, and sometimes provides some strange sightings. The latest of these, thanks to the cold weather, was a group of a dozen Eastern Phoebes foraging on the washed-up mat this weekend, along with a few Song Sparrows, a Golden-crowned Kinglet, and a Brown Creeper." John Idzikowski saw a phoebe in the same area on March 28, and noted that the common brown lacewing (see below) is a main food source for early insectivores.
April
will bring new signs of spring every day! We can't fit all of them into
our Updates, but you can see everyone's reports, and share your own, by
clicking on the Owl Button.
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A lacewing. Phoebes and
other insect-eating birds eat emerging insects such as this in early
spring. |
Last time we asked, "During early spring, why are most flying insects near water?"
If you pay attention, you can see butterflies and other land insects early in spring, but insects that hide in trees and on the ground are at risk of freezing if the temperature drops. Water doesn't respond to changes in weather as quickly as air. Once a lake or stream opens in spring, it seldom freezes again. So insects that can hide near the edge of water are more likely to keep their bodies above freezing than those in drier settings. Also, many of the very first insects to emerge in spring are those that spent the winter under water as nymphs, such as emerging aquatic lacewings.
How to Respond to Today's Challenge Questions:
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 #16
3. In the body of your message, give your answer to ONE of the questions
above.
The Next Signs of Spring Update Will Be Posted on April
11, 2003.
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