Trivia Question of the Week

After a one-week hiatus for the holidays (Happy New Year's, everyone!) we're back. This week's trivia question: How many feathers does a bald eagle have?

Hint #1: The average person has about twice as many hairs on their head alone as an eagle has feathers on its entire body.

Hint #2: Just because it's called a "bald" eagle doesn't mean it's actually bald. Bald eagles have feathers on their heads, too.

Hint #3: Eagles have relatively few wing and tail feathers. The long feathers on the wings used for flight? Only 23 on each wing. The tail feathers? 12.

Hint #4: Most of the feathers on an eagle's body are contour feathers, small feathers that give eagles their shape, and down.

Hint #5: The colder the region, the more down feathers an eagle is likely to have. So an bald eagle in Florida probably has fewer total feathers than an Alaskan eagle.

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If you guessed that bald eagles have an average of 7,000 feathers, right on! This number varies seasonally, as well. During the molting season and in the height of summer, when the weather is warmer, eagles have fewer total feathers because of the loss of down.

Trivia Question of the Week

This week's trivia question is appropriately related to eagle migration: How far do bald eagles migrate?

Hint #1: It's not nearly as far as an arctic tern. 

Hint #2: We've determined these distances through the use of leg bands and telemetry.

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Trivia Question of the Week

Last week, when we posted about the capture and processing of bald eagles, we mentioned that, up until five years of age, eagle molting patterns can be used to determine how old a bird is. Past five years of age, when eagles reach adulthood and take on the characteristic appearance of their species, with a white head and tail, it's impossible to tell how old they are. So, how long do bald eagles live?

Hint #1: The fact that eagles don't mature until five years of age suggests that they're fairly long-lived-- animals that live shorter lives mature earlier.

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Trivia Question of the Week

With plenty of eagles here already and more on the way, this week's question is appropriately eagle-themed.

What is the grip strength of an adult bald eagle?

Hint #1: The tendons in bird's legs have tiny ridges on them that interlock with the tendon sheaths when flexed, holding the talons closed without any additional effort on the part of the bird. Ever wonder why birds don't fall off branches while they're sleeping? It's because the tendons in their feet are locked in place.

Hint #2: The largest species of eagle in the world, the Harpy Eagle, has enough grip strength to crush the bones of large mammals.

Hint #3: Bald eagles may not be able to crush large mammal bones, but they can definitely do some damage to a human wrist.

Hint #4: Their grip strength allows them to pull salmon equal to their own weight from the water.

Hint #5: An eagle's grip strength is more than 10 times that of a human hand.

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If you guessed 400 pounds per square inch (psi), then you are a true ornithology nerd champion and know far more about bald eagles than is healthy anyone else. The grip strength of the average adult human, by comparison, is only about 20 psi.

Trivia Question of the Week

This week's question:

What is the heaviest species of bird in North America?

Hint #1: Although the largest species of bird in North American is the California Condor, this bird has condors beat in the heavyweight category.

Hint #2: Most of their range is centered in Alaska and western provinces in Canada, but they can also be found in parts of Idaho, Wyoming, South Dakota, Nebraska, Michigan, Iowa, and Minnesota, among other locales in the northern US.

Hint #3: Along with being the heaviest bird in North America, this species is the largest extant (still in existence) species of waterfowl in the world.

Hint #4: These animals are large and slow moving, but are often associated with beauty and grace.

Hint #5: They are white.

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If you guessed Trumpeter Swan, then you are correct. The average weight of adult trumpeter swans is between 15 and 30 pounds. These birds often mate for life, and can have a lifespan over 20 years in the wild. Because of their large size and slow flight, trumpeter swans were extensively hunted in the 19th and 20th century, and were extirpated from large parts of their former range. Today, Alaska maintains the largest number of breeding pairs of these birds. Why are they called trumpeter swans? They have a unique and somewhat melodic honk, of course, a bit like a trumpet:

Curious about how trumpeter swans compare in size to bald eagles? Check out this incredible series of photographs captured by photographer Tom Carver in British Columbia of a bald eagle attacking a trumpeter swan in flight!

Trivia Question of the Week

Time for the TQOTW!

How much salmon can a brown bear consume in a single day?

Hint #1: A lot.

Hint #2: No, seriously. A lot.

Hint #3: Dieticians recommend around 2,000 calories per day for the average American adult. For brown bears? Well, let's just say that 65,000 calories is more typical, and 100,000 isn't abnormal when the salmon are running strong.

Hint #4: You would need to eat around 180 servings of salmon to match a brown bear's maximum daily consumption.

Hint #5: Did I mention it's a lot of salmon?

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Brown bears can consume up to 100 pounds, or around 40 salmon (depending on the size of the fish) each day. These figures are likely most relevant when there are a lot of salmon available. Average salmon consumption rates are probably between 55 and 75 pounds of fish per bear per day! Keep in mind that bears can also eat less salmon, and make up the additional calories by eating berries-- wild blueberries, devil's club, watermelon berries, salmon berries, currant, and cranberries, among others. Grasses, invertebrates, and carrion are on the brown bear's menu as well.

The Chum are Coming!

Over the past couple weeks, the Sockeye runs have been slowing down. Most of the Sockeye in the spawning areas have now died, and few new Sockeye appear each day. Carcasses litter the streams, ponds, and banks. We've gradually seen less activity on our trail cameras-- fewer bears are visiting key feeding areas, and we come across fewer partially consumed carcasses along bear trails. But the bears have no need to be concerned. There are plenty of other fish in the stream!

Pink salmon are still running, although their numbers have decreased, too. Coho salmon also continue to spawn, but spawn in much lower densities and across larger areas than Sockeye, so it's more difficult to locate their spawning grounds. The bears' next big target, though (and ours, too, for our trail cameras) are the Chum. Just last week, there were only a few fish in this spawning channel off of Herman Creek. Already, the densities are quickly increasing:

Chum salmon are also called Dog and Keta. Keta is the name typically used by canning companies (after all, who wants to eat "chum" anyway?). Chum and Pink salmon are the least commercially valuable fish. Most commercial fishing and canning operations prefer King and Sockeye, but many subsistence fishers in this region like Chum just fine-- especially when smoked, fresh-caught Chum has good flavor.

Chum salmon spawn in autumn, from roughly the end of August through the winter, or at least until the rivers freeze enough to prevent their travel upstream. Chum spawn by the hundreds of thousands, and much like Sockeye they pack themselves into their spawning areas. Chum can pack themselves in even greater densities than the Sockeye. Sockeye are limited by available fry rearing habitat-- once their eggs hatch the young salmon fry need suitable places to grow for a year or two before migrating to sea. Thus, Sockeye need good places to lay their eggs that are also in areas fit for little fish to grow.

Chum, however, are limited only by spawning habitat. Their fry migrate to sea more or less immediately after hatching. Chum salmon don't need to find suitable places for their fry to grow, only good spots for the eggs to hatch. As long as they can locate nice, rocky substrate with good water flow, they can spawn, so Chum find whatever spawning habitat is available, even if there are already hundreds of other fish around. This makes them easy for wildlife to access. Just walk up to the water and grab one!

With the weather quickly cooling and the Chum beginning to run, the eagles are beginning to congregate. We've started to see far more eagles around Haines recently. Gradually over the next month, the water level of the Chilkat River will drop, exposing the river flats and providing many shallow areas for wildlife to access fish. The Chum run will increase, until the braided areas of the Chilkat are packed with fish. And, as temperatures continue to decrease and freezing begins elsewhere along the coast and in the interior, more and more eagles will travel to Haines to feast on Chum through the beginning of winter.

We will continue to set our trail cameras out to capture wildlife feeding on salmon. At the end of this week, we will take down our last set of trail cameras from the Sockeye runs, and, starting next week, will set our cameras on Chum spawning areas and on higher elevation wildlife trails. Once the eagles begin arriving en mass, we will also start working on the second part of our research here-- looking into eagle migratory behavior!

Trivia Question of the Week

This week's Trivia Question comes to you from our trail cameras! It's a little tougher this week:

What type of animal was captured in this photograph?

(You can click the image to view a larger version)

Hint #1: This photo was taken with an infrared flash at night, so colors won't be there to help you.

Hint #2: The animal in question is in the bottom left-hand part of the frame.

Hint #3: It may seem obvious to some, but it's worth pointing out: this animal is nocturnal.

Hint #4: It's facing away from the camera-- what we're seeing here is, predominately, its back.

Hint #5: This animal is a bird of prey.

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Did you guess Great Horned Owl? If you did, congratulations! Want to helps us identify some other animals?

One of the trickiest aspects of using trail cameras is that the photographs we capture aren't always straightforward. Animals sometimes move quickly across the frame, and the shutter speed of the cameras won't be high enough to prevent motion blur. Sometimes, animals get too close to the cameras and the flash reflects back into the lens, causing white-out or blown highlights. Some animals will be hovering around the edges of the camera's field of view, and only parts of them- tails, feet, the curve of their rump- might end up being captured. Photos taken at night can be particularly difficult because there are no colors. As humans, we rely on colors and color patterns to identify a lot of different animal species-- tough to do when everything is showing in gray-scale!

Did you have difficulty identifying the owl in this photograph? You're not alone. Correctly identifying the species in trail camera photographs is critical for later data analysis, so it can be time consuming and trying to sort through hundreds of photos and pick out the different types of animals in each. Sometimes we find images we really can't identify. With those, we have to do our best to determine the animal's family, at the very least. Is it a mustelid (member of the weasel family, like a mink, marten, ermine, otter, etc.)? Canid (coyote, wolf, fox)? Ursid (brown bear, black bear)?

We also rely a great deal on natural history (knowledge of the animals living in an area and their habits) and contextual cues. For example, wolves aren't likely to be seen close to town, so an shaky image of something dog-like is probably a coyote or domestic dog. River otters won't be found far from water, so an image of a large weasel-like animal captured with a camera on a high altitude trail a mile away from the nearest stream is probably a marten. If one set of photographs is blurry, but there is a photo taken a couple minutes before or afterward of a mink, the blurry photos are probably also mink-- it's uncommon to capture photographs of two completely different animals within a few minutes of one another, unless they're, say, different types of birds feeding along a spawning area.

Here are a few other tricky photos for you to try out:

See the hump in the bottom part of the frame? Any guesses? This one is probably a marten.

In the lower part of the frame, just to the left of center, see the lighter-colored animal against the dark background? This is likely a mink.

See the weasel-like animal just below and left of the center of the photo? This one is probably a mink, too.

If you enjoyed looking at these photos and trying to figure out what you're seeing, you might be able to participate directly in projects like ours in the near future. Yiwei is currently working on developing an interactive game for Facebook that will allow users to work in teams to help tag photos just like these.

More Trail Camera Photos

We've had our trail cameras up for just two weeks, and we've already been getting some great photos. Check out some pictures from our most recent download!

As usual, there are A LOT of bears:

 Look at the size of that Sockeye!

Who's there!?

Someone needs to lay off the salmon....

It's not all bears, though! Look at this raven and great blue heron:

And my personal favorite picture of the week-- we had a couple of wolves stop by! Here's a shot of one of them:

Trivia Question of the Week

It's time for the Trivia Question of the Week! This week's question:

How fast can brown bears run?

Hint #1: If a brown bear were running through a School Zone, it would break the speed limit law.

Hint #2: They can't outpace foxes, coyotes, or wolves.

Hint #3: Usain Bolt wouldn't have a chance at beating a brown bear in a sprint.

Hint #4: In a 1 km race against a cheetah, the cheetah would reach the finish line in half the time it would take the brown bear.

Hint #5: A brown bear probably would have made it out of the Boston Molasses Disaster alive.

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If you guessed 35 miles per hour, you're correct! Brown bears can run at up to 35 mph for a couple miles, and bears have been recorded sprinting at upwards to 40 mph over short distances! Yikes! The fastest human footspeed on record is just under 28 mph, whereas cheetah regularly sprint distances at 70 mph. The take-away message here? Don't run from bears! :)

Trivia Question of the Week

Alright, time for the trivia question of the week! This week's question:

What is the largest bird in the United States?

Hint #1: The species neared extinction in the 1970s

Hint #2: The decline was likely caused by a combination of factors: habitat loss, poisoning, and lead ingestion

Hint #3: They have a wingspan of over 10 feet, can weigh up to 30 pounds, and can live up to 60 years in the wild

Hint #4: They are scavengers

Hint #5: They live in California

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If you guessed California Condor (Gymnogyps californianus), you're correct! California Condor once ranged over the entire western United States, but today they're one of the most endangered species in the world, and their habitat is limited to parts of California and Arizona. Just over 100 birds live in the wild, and most of these were captive-bred animals that are still very closely monitored and regularly fed. The photo above is an image of a California Condor in Grand Canyon National Park.

So, was that a trick question? ;)

The Bald Eagle (Haliaeetus leucocephalus) is no lightweight either-- it's the largest raptor (bird of prey) in the United States. With a wingspan between 6 and 8 feet in length and weights ranging between 7 and 14 pounds, Bald Eagles may not be as large or hefty as California Condors, but they are definitely big birds. Just check out the size of their tracks!

It's Salmon Time!

The salmon are starting to spawn in earnest. Salmon spawn throughout the year, although most species' runs are concentrated between August and December. Different species spawn in different habitats and up different watersheds, at different times of year, so for wildlife that feed on salmon, the entire fall is a veritable smorgasbord of delicious food! Check out this great article published online by the University of Washington about diversity in the way salmon spawn.

There are five different species of salmon that spawn in the eastern Pacific up freshwater rivers and streams along the west coast of the United States: Chum, Coho, Chinook (also known as King salmon), Pink, and Sockeye. 

Yesterday, Jenn, Rigby, Quark and I started scouting areas to set up some of our trail cameras. We wanted to check some Pink and Sockeye spawning areas to make sure there is good fish activity this time of year. Check out this video I took of some Pink salmon spawning in a small creek just off the Chilkat River:

Male and female Pink salmon, as with many species, are sexually dimorphic when they breed. Sexual dimorphism is a term that refers to the fact that males and females have different physical appearances-- Male pink salmon are larger, and grow a hump and hooked jaw, while females remain smaller and streamlined. Pink salmon are also called "Humpies," and I'm sure you can tell why by watching the male Pink salmon in the video above!

There is plenty of evidence of bear activity in these areas. When salmon are high in abundance and bear densities are low, like the Pink salmon at this creek not far outside of Haines, bears high-grade salmon, eating only the most fat-rich parts of the salmon, including the roe (eggs), brains, and sometimes the skin, which often has a fatty layer underneath. Bears then leave the remnants of the salmon carcasses on the stream bank, where they're later accessed by scavengers, or sometimes washed back into the stream.

WARNING! If you don't want to see pictures of dead salmon, don't look below! (But I promise they're not super graphic... this time!)

This is a picture of two Pink salmon, one male and one female, that a bear left on the creek bank. Note that the bear was high-grading these fish: the female, on the left, had only the roe removed; the male, on the right, was missing its brain. Otherwise the carcasses were intact! It may seem wasteful to us, but bears have only a few short months this time of year to put on hundreds of pounds of weight to survive their hibernation during winter. The best way to put on weight is to eat only the fattiest, richest, and most caloric foods. No sense in filling up on muscle-- brains and eggs are the way to go.

We scouted some additional areas yesterday for Sockeye salmon, one which we'll revisit next week to install trail cameras. Before too long, we'll be able to share photos of scavengers that help clean up these leftover carcasses. Until then, you'll have to be content with this scenic picture of Nataga Creek, near its confluence with the Kelsall River.

Kickstarter Update-- 30 days remaining!

Hi everyone!

We have just 30 days left for our Kickstarter project. If you haven't had a chance yet, check out our Kickstarter page!

A huge thank-you to those of you who have pledged to support us. We're nearing 15% of our funding goal. We have a long way to go, so the coming month will be extremely important. Please help us spread the word through Facebook, Twitter or personal emails to individuals who might be interested in salmon, wildlife, Alaska, or science. Even if they don't choose to donate, we want people to learn about our project and get excited about our research!

Please help us continue to spread the word about our work, and of course,  consider contributing if you can! Donations as small as $1 are accepted, and every little bit helps.

Keep checking back for regular updates.

Cheers,
Rachel, Yiwei and Taal

Kickstarting Science!

Hi everyone!

We are very excited to announce the launch of our Kickstarter fundraising page!

Kickstarter is a website that helps projects get started with donations from all over the world. We have set a goal to reach $10,000 by June 30th, 2012. Funding is awarded all or nothing, which means if we don't reach our fundraising goals, we get nothing. So please consider donating if you are interested in supporting science and conservation.

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