Stories tagged migration

Jun
29
2006

Whooping Cranes: Whooping cranes.  Photo courtesy Hedgeman.
Whooping Cranes: Whooping cranes. Photo courtesy Hedgeman.

On June 22, two whooping crane chicks hatched at the Necedah National Wildlife Refuge in Wisconsin. These are the first wild chicks that have hatched in the Midwest in over 100 years.

The two chicks are offspring of a pair of whooping cranes that are a part of the Whooping Crane Eastern Partnership (WCEP), a collaboration of non-profit organizations, individuals and government agencies whose goal is to bring a migratory flock of whooping cranes back to eastern North America. The hatching of these two chicks is a major milestone in this effort.

Whooping Crane Migration

Operation Migration teaches a migratory route to endangered birds. To do so, they raise young whooping cranes in isolation, which then fledge over their future breeding territory in Wisconsin. When the time comes to migrate, they follow an ultralight aircraft from the Necedah National Wildlife Refuge in Wisconsin to the Chassahowitzka National Wildlife Refuge in Florida. Once they have learned the migratory route they migrate on their own the following year.

Whooping Cranes Migrating: Because of Operation Migration whooping cranes can make the migratory flights south in the fall and north in the spring on their own.  Photo courtesy thelastminute.
Whooping Cranes Migrating: Because of Operation Migration whooping cranes can make the migratory flights south in the fall and north in the spring on their own. Photo courtesy thelastminute.
Reintroduction of an endangered species

Wild whooping cranes are an endangered species that before this project only existed in the wild in two flocks. One is a non-migratory flock in Florida and the other is a migratory flock that summers in Wood Buffalo National Park in Canada and winters at Aransas National Wildlife Refuge in Texas. The National Audubon Society's 2006 list of the top ten endangered birds in the United States lists the whooping crane third behind the ivory-billed woodpecker and California condor.

Due to the risk of both of the natural flocks being wiped out by a single event such as a hurricane, an additional, experimental, flock of whooping cranes was established in the fall 2001. 64 of the 76 birds released for this experimental migratory flock have survived to April, 2006.

And now we can add two more to that population count.

Oct
18
2005


Whooping cranes and an ultralight: Because of Operation Migration, now in its fifth year, 40 adult birds in the flock now make the migratory flights south in the fall and north in the spring on their own. Photo © Operation Migration


Whooping crane: An adult whooping crane (Photo courtesy USGS)

On Friday, a group of endangered whooping cranes took to the skies, migrating from Necedah, Wisconsin, to their winter habitat in Florida—1,200 miles away.

The 20 cranes, which were hatched and raised in captivity, have to be taught to migrate. (Whooping cranes learned their migration route by following their parents, but the knowledge was lost when the population dwindled and no wild birds used the flyway.) So Operation Migration's pilots in ultralight planes lead the birds south.

The birds' route takes them from the Necedah National Wildlife Refuge, in Wisconsin, to the Chassahowitzka National Wildlife Refuge in Florida. Read the Operation Migration field journal to see where the flock is today and what's been happening to them.

(The Patuxent Wildlife Research Center, which also helps to raise endangered whooping cranes, has links to lots more resources.)

May
05
2005

Every winter Monarch butterflies head south to Mexico to avoid cold temperatures.

monarch butterfly on a branch
Want to learn more about Monarchs and other butterflies? Visit the Science Museum's Monarchs and Migration website

But how in the world do they know how to get there? Well, they don't follow Highway 35, that's for sure. It turns out that monarchs can detect the sun's ultraviolet (UV) rays even when it's cloudy out. (UV rays are the part of sunlight that causes sunburn.)

Up until now we didn't know how butterflies used this UV information to fly south. Researchers led by Steven Reppert at the University of Massachusetts Medical School ran some monarchs through a flight simulator and discovered their secrets. It turns out that monarchs' eyes are very sensitive to UV light. They synch this UV information up with a natural clock in their brain. By combining these two bits of information, monarchs are able to determine the angle of the sun and always head due south. Sailors used a similar method (a sextant) to navigate around the world before the invention of compasses. Monarchs can do the trick all by themselves, though.

Do you think you could walk due south, from Minnesota to Mexico even on a cloudy day?

Some tagged monarchs have travelled more than 265 miles in a single day! Not bad for an insect...

Journey North and Monarchs in the Classroom also have cool websites (complete with projects and "Citizen Science" opportunities) about the annual Monarch butterfly migration.

Mar
22
2005

Word around the museum is that, if you're lucky and looking out the Mississippi River Gallery's big windows (Level 5) at the right time, you might see one of two bald eagles that have been hanging out along our stretch of the river.

Once an endangered species, bald eagles have made a spectacular comeback since the pesticide DDT was banned in the United States in 1972. In our area, eagles are becoming common sightings. Each year, the Mississippi River Valley becomes a "highway" for eagles traveling from the northern summer homes to their southern winter homes. But many eagles spend all year here in Minnesota. In fact, Minnesota and Wisconsin are home to the largest nesting population of bald eagles in the United States outside of Alaska.

Mornings and evenings, you might see eagles soaring on thermals or diving for fish, their primary food. During the day, you're likely to see them perched in large trees near the river's edge.

How can you identify a bald eagle? Well, they're big, with wingspans of up to 7 1/2 feet. You'll often see them soaring or gliding with flat wings. When they do flap, wingbeats are slow and powerful. You usually see them near open water. And adult eagles have brown bodies with white heads and tails. For more tips, Visit the Indiana Department of Natural Resources.

Where to see eagles during the winter

Where to see eagles in Red Wing

Where to see eagles in Wabasha

Find out about where you can see eagles during the summer, complete with map.

A cool site with lots of questions and answers about bald eagles.

The Raptor Center at the University of Minnesota provides medical care for sick and injured birds of prey, including eagles.

Mar
09
2005

The Great Gray Owl, the largest owl in North America, normally lives in a wide swath of forests sweeping from Alaska across to northeastern Canada. However, this winter Minnesotans have spotted the giant owls all over the state. The Great Gray Owl is a hunter that mostly eats voles, small rodents similar to mice. Last fall, the vole population in Canada fell to its lowest levels since 1992. (Because cold, wet weather is hard on the voles, the population has headed south.) As a result, the Great Grey Owl has had a hard time finding food up north. It has followed its food source and ended up here in Minnesota, south of its usual range.