Thanks for taking the time to chat with Melissa Cady, who is a wildlife biologist with the U.S. Forest Service. We appreciated getting all of your great questions and the questions and answers are below. There were a lot of excellent questions, and check to see if your question might have been asked by another person.

Ms. Cady is stationed at the Wrangell Ranger District of the Tongass National Forest. Ms. Cady’s primary research interests include monitoring and taking inventory of land birds.  She received a B.A. in biology from Hendrix College, Conway, Arkansas in 1995, and a M.S. in wildlife biology from Colorado State University, Fort Collins, Colorado in 2000.  She has worked for the government as a wildlife biologist or technician since 1995.   

The following are the questions and answers from the chat held on May 3, 2007.

---

Zack from California, PA: Out of all the sea birds, what bird can fly the fastest? How many sea birds travel over 10,000 miles?

Melissa Cady:  A study of Atlantic and Antarctic seabirds using tracking radar and an optical rangefinder placed on a ship at sea found that, of the species they studied, albatrosses and giant petrels flew the fastest at around 50 mph.  These are large, seagull like birds of the open ocean.  These speeds were achieved through a combination of wave soaring and dynamic soaring, meaning that they can fly at these speeds largely without flapping their wings, but by positioning their bodies carefully with respect to wind and waves on the ocean.  This study was conducted by Thomas Alerstam et al. and is reported in the journal Biological Sciences, Vol. 340, No. 1291 (Apr. 29, 1993), pp. 55-67.

Some shorebirds migrating with a tailwind can fly as fast as 60 mph!

Several species of birds travel over 10,000 miles annually.  Arctic Terns that visit us here on the Stikine River each summer migrate to Antarctica each year during our winter.  They enjoy the Austral summer, then return to Alaska each spring for an annual round trip migration of 40,000 miles. The gold medal for the longest migration flight belongs to a small seabird called the Sooty Shearwater. A team of scientists recently found that this bird has the longest migration route of any species in the animal kingdom. Sooty shearwaters travel more than 64,000 kilometers (39,000 miles) in a single year. That's about one-and-a-half times the distance around the globe at the equator.  Find out more at http://www.sciencenewsforkids.org/articles/20061004/Feature1.asp

Some shorebird species are also among the world’s top long-distance migrants.  Pectoral Sandpipers migrate between southern south America and Siberia.  And Bar-tailed Godwits make the longest non-stop migration flight of any species at 6500 miles between Alaska and New Zealand.  These birds don’t stop to rest anywhere along the way, and have to flap their wings the entire time; no soaring! 

David from Texas: How can the birds conserve so much energy especially if they are flying for so long and far in the air without stopping to rest?

Melissa Cady: Everything about the way shorebirds are designed helps them conserve the energy they need to make long flights.  Their bodies are very streamlined and efficient for flying through the air.  They have special kinds of fat in their bodies that store a lot of energy with very little weight.  Organs in their bodies not necessary for flight shrink when they are not needed to reduce the weight and make flying easier.  They take advantage of weather and winds when possible to make their migration efficient.  And they know about special places to stop and refuel along the way like the Stikine River Delta, where they may stop and feed on energy-rich invertebrates for 1-3 days as they travel north along the Pacific Flyway.  

Mrs. Peterson from Petersburg, Alaska: Do all the Western Sandpipers migrate or do some stay back?

Melissa Cady: While a few stragglers may be found in their breeding or wintering grounds off-season from time to time, pretty much all Western Sandpipers migrate.  Adult birds stay with young in family groups until the young birds are able to fly.  Adults depart the breeding grounds to head south in mid-summer, and the young start their migration 2-3 weeks later, embarking on the long and unfamiliar trip without their parents.  While it may seem a little scary for these young birds to migrate without their parents, leaving later gives the chicks extra time to grow strong before migration and to fatten up without the added competition from the adults.

Ben from Galveston Island, Texas: We have hummingbirds that migrate through Galveston Island....are there hummingbirds that migrate through your area as well?

Melissa Cady: Yes, Rufous Hummingbirds migrate through and breed in Southeast Alaska including the Stikine River area.  They are the only species of hummingbirds that are regularly seen here.  They arrived in Wrangell where I live around the beginning of April this year, and many are still migrating through.  We are having a late spring this year, so they are making good use of the feeders people have put out for them.

Danielle from California Area School District: do any of the birds ever lay their eggs early while on the trip?

Melissa Cady: I don’t think so.  Their eggs may be forming while they are migrating, but won’t be ready until they arrive on their breeding grounds.

Ian from Petersburg, AK: Will the birds fight back if they are attacked?

Melissa Cady: Yes, most birds will use their bills, their wings, and their feet to fend off attackers.

Dakota from California Area School District: How do you get the radio transmitters back off the bird?

Melissa Cady: They are usually glued on and fall off after a few weeks.

Kyle from Petersburg, AK: How warm do the eggs have to get to hatch?

Melissa Cady: Eggs need to be kept warm by an adult bird, and need to be close to the temperature of the adult’s body.

Josh from California Area School District: How do the radio transmitters work

Melissa Cady: They have a tiny battery that powers a radio with an antenna that sends out a radio signal like a radio station that beeps every second.  When you are close to that radio signal, you can hear it using an antenna, and it can help you to locate that bird again.

Tom from Yakutat Alaska: I have observed mixed flocks of shorebirds at times. Is there a reason why some shorebirds would have more than one species in a single flock?

Melissa Cady: The benefits of flying in a flock are the same whether you are in a mixed or single species flock.  Many species fly in mixed flocks.  Large flocks help protect individuals from predators because there are many more eyes to watch for danger, and because any one individual's chance of being captured by a predator is decreased if there are lots more individuals for the predator to choose from. Similar flocking or herding behavior is common in many other species like fish or zebras.

Lisa from Brooklyn, NY: How long have you been studying birds?

Melissa Cady: 12 years

Chris from Brooklyn, NY: Do birds stay with their parents when they grow up?

Melissa Cady: Not usually, though there are some species that do.  Harris Hawks live and hunt communally.

Ion from California Area School District: Why do birds migrate at all?

Melissa Cady: They follow the food resources and favorable weather conditions that move as the seasons change.

Aaron from Brooklyn, NY: How do these birds mate? Different of the same as humans?

Melissa Cady: A lot like humans, and usually much briefer.  Bald Eagles fly up high and lock talons in mid-air to mate, spiralling toward the ground in a spectacular display, breaking off and flying away just before hitting the ground.

Sara from California Area School District: How many babies do these birds have at one time and over their life time?

Melissa Cady: Birds lay from 1 to 20 or so eggs at a time.  Western Sandpipers lay 4 eggs at a time.  Lifetime productivity is highly variable and depends on how many broods a species raises each year and how long they live.  Most bird species live between 3 and 20 years.

Kelly from Petersburg, AK: Since we had such a late snow melt, will the birds be able to find as much food as in previous years?

Melissa Cady: Most of the habitats at really low elevation have been free of snow long enough for birds to find forage.  The Stikine River Delta has been free of snow for about 3 weeks now.

Tanner from Califorina, PA: What bird has the biggest egg?

Melissa Cady: Ostriches.

Val from Brooklyn: Do birds get along with one another? Are there fights?

Melissa Cady: Mostly.  They sometimes fight, but most fights are not dangerous.

Tanner from Califorina, PA: Do they sing song when they are flying?

Melissa Cady: Some do.

Caitlin from Petersburg, AK: How much food do they need to eat each time they stop?

Melissa Cady: As much as they can.  Some birds will eat enough to put on half their weight in fat before they migrate.

SavanNah from Calirfornia Area Middle School: what is the biggest bird you get there?

Melissa Cady: Trumpeter Swans are heaviest, but Sandhill Cranes are the tallest.

Lisa from Brooklyn, NY: How long can these birds go without food and water? What is their favorite food? 

Melissa Cady: A few days at the most.  They love to eat invertebrates.

JesSa Thompson from California Area Middle School: How many birds are there a year ?????

Melissa Cady: Depends on the species, but all together, MILLIONS!

Quan from Brooklyn, NY: What do the birds do after they leave Alaska? How long do they stay for?

Melissa Cady: They stay in Alaska for the summer and leave in August.  Then they fly south to their wintering grounds in the Lower 48 or Central or South America.

Melissa from Oakton: What kind of work do wildlife biologists do in Alaska? What kind of school or training do you need?

Melissa Cady: Wildlife biologists measure all kinds of things about animals and their habitats.  In Alaska, that often means going to remote places by helicopter, float plane, or boat to take careful notes and make observations about wildlife.  To be a wildlife biologist, you have to go to college and grad school is usually necessary to get a permanent job.  It’s important to learn all you can in science, math and english classes to prepare for this kind of work.  It also helps to go camping a lot and learn about how to survive in and enjoy the outdoors.

Austin from California Area School District: Can a bird fly if some of it's feathers are missing?

Melissa Cady: Yes,  birds regularly replace their feathers and often have a few missing.  Some birds like some species of geese lose all of their feathers at once (called molting), and can’t fly for a short time.

Breann from California Area Middle School: About how many types of birds fly?

Melissa Cady: Most birds can fly.  The main types of birds that can’t fly include rheas and ostriches, kiwis, and penguins.

Gladys Dart School: Why do birds fly in a V pattern?

Melissa Cady: Some scientists think that it saves them energy, because the eddies in the air caused by the leading birds’ wings lifts up the birds behind.

Nora from Texas: Are you able to track some of the shorebirds electronically?

Melissa Cady: Yes, if they have a radio-transmitter.  Some people also track migrating birds using radar.

Lindsay from Manley Hot Springs - AK: Is it common for birds of different species to flock and migrate with bigger birds?

Melissa Cady: Mixed flocks of different species are common, and the different species are usually different sizes.

Aaron from Brooklyn, NY: Why do the birds go to Alaska to mate? Why not some other place?

Melissa Cady: Because during the short summer we have an abundance of plant and insect life that birds can use to feed their young.

Lisa from Brooklyn, NY: How many years do migrating birds live for?

Melissa Cady: It depends on the species, but most birds live from between 3 to 20 years.

Ian from Brooklyn, NY: What is the reason Alaska has no endangered species? Will drilling for oil in Alaska change that?  Thanks.
Melissa Cady: Alaska does have some endangered species, but there are no terrestrial endangered species that live in this part of Alaska near the Stikine River Delta.

Wes from Yakutat Alaska: What is the greatest danger for shorebirds on their migration?
Melissa Cady: I don't know what the greatest danger is, but I suspect predators, bad weather conditions, or the lack of food might be some of the greatest factors.

Abel from Petersburg, AK: Do the little cameras weigh the birds down and slow their flight?
Melissa Cady: I don't know of anyone who puts little cameras on birds, but little radio transmitters are usually less than 1/10 of a bird's body weight. It may slow them down some, but many seem to cope with it really well.

Karl from Petersburg, AK: How big are the eggs of the sandpiper
Melissa Cady: Western Sandpiper eggs are about 1.2 inches.

SaVanNah from California Area Middle School:  What is the smallest bird you usually see ?
Melissa Cady: Rufous Hummingbird

Mitchell from Brooklyn, NY: Thanks for your important work.  Has the Bush Administration shown positive support for the work of the Forest Service to prevent global warming?  Over the past 3 years has the number of species increased, decreased, stayed the same? If it has changed, why?  Thanks.
Melissa Cady: The Forest Service mission is to care for the land and to serve the people; that mission was in place before the Bush Administration took office and will likely remain the same after this administration has passed. As for number of species, our wildlife species have stayed pretty much the same in recent years. We are fortunate that we have no threatened or endangered terrestrial species in our area, and we hope to keep it that way.

Mike from Juneau: How many species do you anticipate this season? Which will be most abundant?
Melissa Cady: Around 150 species will use the Stikine River area this summer. This spring, by far the most abundant bird using the Stikine River Delta will be Western Sandpipers. A large proportion of the entire world's population of this species will stop at this location for 1-3 days this spring to refuel on their way north.

David from Texas: How can the birds conserve so much energy especially if they are flying for so long and far in the air without stopping to rest?
Melissa Cady: Everything about the way shorebirds are designed helps them conserve the energy they need to make long flights. Their bodies are very streamlined and efficient for flying through the air. They have special kinds of fat in their bodies that store a lot of energy with very little weight. Organs in their bodies not necessary for flight shrink when they are not needed to reduce the weight and make flying easier. They take advantage of weather and winds when possible to make their migration efficient. And they know about special places to stop and refuel along the way like the Stikine River Delta, where they may stop and feed on energy-rich invertebrates for 1-3 days as they travel north along the Pacific Flyway.

Garison from Petersburg, AK: How much time does it take a bird to fly a mile?
Melissa Cady: It depends on the bird and the conditions. A shorebird migrating with a tailwind might be able to fly one mile in a minute or about 60 miles an hour.

Mrs. Peterson from Petersburg, Alaska: Do all the Western Sandpipers migrate or do some stay back?
Melissa Cady: While a few stragglers may be found in their breeding or wintering grounds off-season from time to time, pretty much all Western Sandpipers migrate. Adult birds stay with young in family groups until the young birds are able to fly. Adults depart the breeding grounds to head south in mid-summer, and the young start their migration 2-3 weeks later, embarking on the long and unfamiliar trip without their parents. While it may seem a little scary for these young birds to migrate without their parents, leaving later gives the chicks extra time to grow strong before migration and to fatten up without the added competition from the adults.

Alex from Brooklyn, NY: Do birds understand each other with their sounds?  Thanks.
Melissa Cady: Yes. Scientists studying birds have found that many species have specific alarm calls for different kinds of predators that can even be recognized by other species. Some species, like the Common Ravens we have here, have very complex communication based on vocalizations and postures.

Danni from California Area Middle School: Do the birds ever get cold?
Melissa Cady: They probably do from time to time, but they are all wearing waterproof, down jackets that they can puff up or slick down depending on the weather. I'm joking about the jackets, but the down (warm, fluffy feathers) next to their bodies stays dry due to careful care of their outer feathers, so they have a much better system for insulating their bodies than anything humans have devised for themselves.

Atekah from Brooklyn, NY: Do the birds have a good sense to stay away from predators? Thanks.
Melissa Cady: Most of the shorebirds that migrate through the Stikine River stay in large flocks. Large flocks help protect individuals from predators because there are many more eyes to watch for danger, and because any one individual's chance of being captured by a predator is decreased if there are lots more individuals for the predator to choose from. Similar flocking or herding behavior is common in many other species like fish or zebras.

Tyler from California Area Middle School: How big do the birds normally get?
Melissa Cady: Western Sandpipers, which are the most abundant species on the Stikine River Delta each spring, get to be about 6.5 inches long and weigh about 0.91 ounces or 26 grams.

Maria from Flordia: What is your favorite bird?
Melissa Cady: Like my favorite song, my favorite bird also changes from time to time. Right now, the American Dipper is probably my favorite bird. It's a little grey bird that forages in clear swift streams for aquatic invertebrates. They can literally swim underwater with their wings, but they look just like a regular passerine or perching bird like a robin or a sparrow. They have a beautiful song and usually live in beautiful places.

Ben from Virginia: Hi, How many birds are there right now. Are you at the beginning, middle or end of the migration cycle?
Melissa Cady: Two weeks ago, there were several thousand snow geese on the Stikine River Delta. I have not had the opportunity to count birds on the delta this week, but in past years at this time of year, over 100,000 shorebirds were counted on the Delta at one time!

Nikko from Petersburg, Alaska: How can you tell a female from a male?
Melissa Cady: Males and females of many species of birds are easily distinguished by differences in the color or pattern of their feathers or plumage. Other species, like Western Sandpipers are more difficult to tell apart because they are roughly the same size, and their plumage is the same. However, scientists can usually determine the sex of an individual by weighing it, by taking a genetic sample, or by close visual inspection of a bird in the hand. For Western Sandpipers, females are usually slightly larger and heavier than males, with longer bills. However, these differences are difficult to observe in the field and are much easier to judge with a scale and a pair of calipers on a captured bird rather than with a pair of binoculars on a bird in the wild.

Kristy from Virginia: Have you observed any changes due to global warming?
Melissa Cady: Weather has been unusual here in the last few years. We had two very warm dry summers followed by a very cool wet summer with record rainfall in 2006. Record snow falls were recorded this winter all across Southeast Alaska. So people have noticed some unusual weather patters here.

More disturbing and likely more closely related to climate change is a phenomenon called cedar decline. All across Southeast Alaska large stands of yellow cedar trees have been dying as a result of late spring freezing of the roots. It's thought that in the past, those roots would have been protected in the late spring from hard freezes by snow, but in more recent years, the snow has been absent at that time of year, resulting in large die-offs due to frost damage of tree roots.