COWBIRD MIX-UP

A park ranger, exploring a marsh, was enjoying the songs of the birds. The cattails had grown chest high by this June day. A flash of yellow caught the ranger's eye and she saw a beautiful Yellowthroat Warbler leave her nest. The ranger thought about all the people who come to the park to birdwatch and how much they would enjoy seeing this beauty.

As the warbler flew to find food the ranger saw a cowbird quickly drop down into the nest. In just one minute the female cowbird laid one of her eggs and departed.

The ranger knew this would be trouble for the warbler. The warbler would come back and not recognize the difference between her own eggs and the Cowbird's. She would sit on all the eggs to help them hatch. The Cowbird egg would hatch first and the parents would feed the chick. By the time the warbler's eggs hatched, the Cowbird would be much bigger and demand most of the food.

Soon the warbler chicks would get weak and be pushed out of the nest by the Cowbird. The warblers would be good parents to the Cowbird and try to find enough food for this chick. Soon it will be larger than they are.

By the time they finish, the warblers would raise a Cowbird chick but none of their own. Research tells us the populations of songbirds like the warblers are decreasing because Cowbirds now live throughout the United States and Canada.

How did Cowbirds become a problem? They are native birds that once lived only in the prairie areas where large buffalo herds were found. The birds ate the insects that the buffaloes stirred up. Since Cowbirds had to follow the continuous moving buffaloes, female Cowbirds had no time to build nests and raise their young. They adapted by laying an egg in another species nest so that pair of songbirds would raise the chick.

When people removed the buffalo by hunting, Cowbirds started to live near the cattle the people brought. As people cut down the forest and made pastures and fields, the Cowbirds moved throughout the US. Now Cowbirds have the opportunity to find the nests of the birds that live in Indiana Dunes. The number of songbirds in this park and everywhere else is decreasing. This is a critical problem for anyone who loves birds and the park. The rangers do not know what to do about this problem, but they want to teach you a game that will show you how quickly the Cowbirds affected the population of songbirds like the warblers.

1. Cut out the words "nest", "territory" "eggs hatched", "found a mate" and "cowbird". Glue them on a card.
2. Use the concept of a baseball diamond and designate four bases. Have the students randomly choose a base to stand near. (There needs to be at least eight students near each base. If the group is small only make three bases.)
3. Place the cards in the center. Instruct the students to pick up one card and go back to their base.
4. Have each student secretly look at his/her card. The students with the "found a mate" cards should raise their hands. Groups without a mate can't reproduce.
5. Ask each group with a mate to reveal a "food", "territory", and "eggs hatched" card. If all of these cards are present, the parents raise their chicks successfully.
6. After one or two rounds of the game, explain how the deep woods habitat is changed as people cut down the trees. Cowbirds now become plentiful in the open areas and fly into the woods to lay their eggs in a songbird’s nest. Place a Cowbird card in with the rest and play the game again.
7. Each time a Cowbird is successfully raised by the songbird add another Cowbird card. Soon everyone will be raising Cowbirds.

Copycat page – Cowbird Mix-up – four cowbird cards for any size class.

Copycat page – Cowbird Mix-up - Need eight photocopies of each of the following labels for a class of 32 students

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