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Alaska's Bumblebees (mp3, Transcript)


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Alaska's Bumblebees

On a spring day a fat bumblebee sips nectar from a tall blue cornflower, before moving on to a cluster of lupine. This is a western bumblebee, the most common bee in Alaska. She's also a queen. Worker bees don't overwinter in Alaska. The queen emerges in the spring, solo, and establishes a hive, laying eggs and nurturing the first batch of worker bees that by summer will be busily helping with the hive.

Bumblebees do pretty well in Alaska. Fat and furry, they're able to regulate their body temperature and they tolerate cooler weather better than other bees. There are 46 bumblebee species in North America and 23 species are found in Alaska - including the arctic bumblebee, Bombus Polaris, one of only two bee species found in the arctic.

The Western bumble is widespread in the western US and Alaska and is an excellent generalist pollinator, pollinating a wide range of flowers. Over the summer, worker bees gather nectar and pollen, and the queen lays eggs. In late summer and fall, she produces male and female offspring that can reproduce. In the fall, the old queen and the workers die and some female bees - with the potential to become next year's queens - survive and overwinter, hibernating and emerging in the spring to start new colonies.

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Alaska's Dragons (mp3, Transcript)


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Alaska's dragons

On a languid summer day, a fat brown and black dragonfly cruises the horsetails at the edge of a shallow pond. It's a four-spotted skimmer, the Alaska state insect, one of about 30 species of dragonflies found in Alaska. This skimmer is patrolling his territory, but he's not hunting for food, he's looking for a mate.

Dragonflies live just a month or two as the maneuverable aerial hunters we see, mating in flight and laying eggs in water. Dragonflies spend most of their lives underwater as major predators of aquatic insects. With a lightning strike of their powerful jaws, dragonfly larvae can even take small fish. Depending on the species, dragonflies may spend a few weeks, or as much as five years, as aquatic larvae, before they climb out of the water onto a small twig and metamorphose into adults.

Biologists Bob Armstrong and John Hudson have documented the dragonflies of Alaska and created an identification guide. These insects range from small damselflies - like the tiny green sedge sprite, up to the five inch long lake darner, the largest dragonfly in state. Azure darners cruise the shores of Prudhoe Bay in the Arctic, black meadowhawks skim the marshy shores of the Interior, and delicate emeralds feast on mosquitoes in the southeast Rainforest.

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Alaska's Poisonous Newts (mp3)


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Arctic Bumblebee (mp3, Transcript)


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The brief busy life of Arctic bumblebee

In summer, flowers add color to the Arctic tundra. Monk's hood, lousewort, avens, and willow catkins bloom and begin receiving visitors - nectar-sipping pollinators. Important among them is the fuzzy Arctic bumblebee, the queen of beasts among the tundra flowers. Big and hairy, Bombus polaris is exquisitely adapted to life in the north. The Arctic bumblebees' ability to fly at low temperatures and for long distances makes them particularly important pollinators.

One fat bee crawls from a purple monk's hood blossom and heads to the next patch of flowers. She emerged from hibernation in May as the tundra began warming. She spent nine months in a mouse nest or some other subterranean burrow suspended in an almost lifeless state of hibernation. Already mated last fall, this queen is the sole survivor of her colony and has a busy summer ahead of her. Right now, she's a queen with no subjects and a date with death this coming fall. She has eggs to lay, and the eggs must hatch, and the larvae must grow, pupate, and develop into adults.

The queen's first batch will develop into workers bees: small sterile females who will enlarge the nest, forage, and tend the next generation of bees. She will produce a second brood in late summer that includes males (called drones) and up to a hundred fertile females who are candidates for next year's queen. The drones' sole function is to fertilize the females.

Bumblebee colonies in temperate climates generally produce hundreds of successful queens. In the Arctic, only one queen per colony on average will survive the winter to renew the life cycle.

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Benefits of Fire (mp3)


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Berner's Bay Spring (mp3)


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Busy Shrew (mp3, Transcript)


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Busy Shrew

It's a wet Sunday morning in early June in Southeast Alaska, and we're packing up our camp after an overnight at the beach. The rainforest has lived up to its name, and as I trudge down the trail with our soggy gear, I see a tiny brown shape dart under the moss at the base of a spruce tree. A close look reveals a shrew busily rooting around in the moss. My chores are forgotten as I watch this hungry, ping-pong ball size fur ball with a long, pointed nose bustling about his search for bugs and worms. This is the smallest mammal in Alaska and weighs about as much as a nickel.

Shrews are not rodents, they are related to moles, and moles don't live in Alaska. Shrews have poor eyesight and rely on their keen sense of smell to find food. They are voracious with a fast metabolism and eat two or three times their body weight every day. That's apparent from this little guy's behavior, he is oblivious to me, and totally focused on rooting out morsels from the moss and a leaf litter. He's finding little spruce buds, which he peels before he eats, and at one point he gobbles down a small spider. Shrews eat seeds and some vegetation, but grubs, worms and insects are their bread and butter. Some species are excellent swimmers and get most of their food from streams and ponds.

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Coping With Winter (mp3)


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Copper River Delta (mp3)


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Cottonwood (mp3, Transcript)


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Walking along a favorite Creekside trail in April, I catch a whiff of cottonwood buds. It's a welcome sign of spring - the rich, honey-vanilla scent of ripe cottonwood buds as the leaves first emerge in the warming, lengthening days. The source of the scent, a sticky brown goo that coats the cottonwood buds, is extracted commercially for use in cosmetics and medicines, and used by Alaskans in balms and salves.

Cottonwoods are named for the tufts of fluffy white cotton that surrounds the seeds and helps them disperse in late summer, much like the fluff that comes from Fireweed.

Cottonwoods are the largest broadleaf trees in Alaska and they are the fastest growing trees in North America. They're found in river valleys and lowlands of Southeast and Southcentral Alaska and can grow to 100 feet in height, their thick trunks girded with grey, deeply fissured bark. Eagles build their platform nests in cottonwoods, and great blue herons find the broad crowns of the big trees attractive for their nesting colonies. Hares and moose eat the leaves, buds and catkins.

Related to fast-growing willows and poplars, cottonwoods share their remarkable ability to propagate from cut limbs and broken branches. Cottonwoods produce such high levels of rooting hormone that cut branches placed in wet ground will root and grow, and cut branches placed in water will stimulate rooting in other plants as well.

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Dive Research (mp3, Transcript)


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Dive Research

Fifty feet beneath the green waters of Alaska's Inside Passage, a pair of divers hunts for sea cucumbers. Clad in bulky dry suits, they paw through a patch of kelp and note the presence of one of the slug like echinoderms. These aren't commercial divers collecting sea cucumbers to sell; they're Fish and Game biologists surveying the population.

The Fish and Game diving program provides valuable biological information and stock assessments to the resource managers throughout Southeast Alaska. This important resource data that helps biologists manage the herring, herring roe, red urchin and gooey-duck clam fisheries. Sea cucumber surveys help set the harvest guidelines for the fall dive fishery. Divers also survey abalone, and are helping to document and control an invasive tunicate near Sitka.

Diving in the cold water of Alaska is a gear intensive undertaking. Divers wear warm undergarments, like long underwear made out of a sleeping bag, under a water impenetrable dry suit. A scuba tank filled with a mix of pressurized oxygen and nitrogen provides air to breathe underwater, as well as a way to pressurize the suit to compensate for the increase in water pressure as they descend. Because dry suits are very buoyant most divers carry 32 pounds of weights in their dry suit pockets, four to eight pounds in the shoulder pockets and four pounds around their ankles to keep them submerged.

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Elevational Migrations (mp3, Transcript)


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Elevational migrations

The seasonal migrations of waterfowl are well known. When geese that nest in Alaska fly south to Oregon for the winter, it's a latitudinal migration, from high or northern latitudes to low or southern latitudes. Some animals do a different kind of seasonal migration in the fall, to warmer locations, but they don't move thousands of miles. These birds and animals do elevational migrations, and move from high elevations to lower elevations.

In spring and summer, ptarmigan nest and feed in alpine areas and in the upper reaches of timber. In early fall they move downslope and seek food and shelter at lower elevations. In most parts of Alaska these movements between summer and winter ranges encompass just a few miles.

Generally speaking, a 1,000 foot descent in elevation equals a temperature change of about three-and-a-half degrees Fahrenheit. So a ptarmigan that moves from 3,500 feet to 1,500 feet will experience temperatures that are on average seven degrees warmer. In addition, winds are usually milder at lower elevations. The ptarmigan's descent of 2,000 feet may require a short flight, but it is equivalent to a migration southward of several hundred miles.

The American dipper, a familiar streamside songbird, does not migrate south but will move down to lower elevations in winter. Mountain goats and Sitka black-tailed deer also make seasonal migrations to lower elevation, returning to the high country in the spring and summer.

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Explosive Breeders (mp3, Transcript)


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Explosive breeders

The evening light is lingering over a small muskeg pond set in the scrubby shore pines of Southeast Alaska. It's early May, the days are getting longer and the snow has finally melted. The first mosquitoes are coming out, but otherwise all seems still. But there's activity in the pond - ripples and splashes in the vegetation under the water, and an unusual chirping call. Two eyes appear at the surface, and the wide mouth of a western toad. The short, frantic breeding season for western toads is underway.

Different species of frogs and toads tend to breed at the same time each year, but the exact time varies depending on weather. Western toads - and Alaska's other relatively common amphibian, the wood frog - breed early. They are explosive breeders, meaning they gather in large numbers for just a few days. Prolonged breeders, such as treefrogs and bullfrogs, which are not found in Alaska, will breed over a period of several weeks or longer.

Mating tactics vary depending on whether the species are explosive or prolonged breeders. For prolonged breeders, males establish territories and defend these prime calling sites from other males. Dominant males in prime sites attract more females. Satellite males, which are often smaller, quietly wait nearby to intercept an approaching female. In some species, satellite males may steal the perch of a dominant male that leaves to breed with a receptive female. Explosive breeders also claim prime sites, but males will temporarily abandon calling to swim after and grab frogs moving nearby in hopes of intercepting receptive females.

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Fire-Breathing Dragonflies (mp3, Transcript)


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Fire Breathing Dragonflies

The discovery of a new species of dragonfly in Alaska has the entomology world buzzing.

The new dragonfly inhabits the remote regions of Northwestern Alaska, and it has a remarkable attribute.

The insect is capable of combustive exhalation, according to Dr. Nat Beedle of the University of Alaska Zoology Department, who discovered the new insect. "Basically, it can shoot fire out its mouth like a blowtorch."

The fire breathing dragonfly has gone undiscovered because it spends most of its life as an aquatic larvae, morphing into adult form to mate. Mating occurs around the summer solstice over water.

"I guess no one noticed the flame shooting out its mouth because of the 24-hour daylight," said Dr. Beedle.

The flame is produced by a biological process similar to a stinkbug's skunk-like excretions, which it squirts at would-be predators. "A fire breathing dragonfly is pretty cool," Dr. Beedle said, "But a beetle that could shoot a flame out its butt would be really awesome."

The fire-breathing dragonflies can control the flame, much as a phaser can be set to stun or kill. Beedle said the low setting is used to cook their food. They'll toast a bumblebee in flight like a marshmallow, Beedle said. The males offer roasted bugs to the females as part of their pre-mating courtship ritual.

Like the stinkbug, the dragonfly uses its power for protection against predators, such as swallows and flycatchers. Beedle said he watched a northern bog swallow swoop over a pond and intercept a fire breathing dragonfly with disastrous results.

"It was vaporized - there was nothing left but the stench of burning feathers," he said.

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Frog Blood Sugar (mp3, Transcript)


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Frozen frogs

A chorus of frogs fills the air on a summer night in the Pacific Northwest. When fall comes and this lake in the Cascade Mountains cools, the frogs will burrow into the leaves and forest litter and hibernate below the frost line. Insulated by soil and a layer of snow, their bodies cool to temperatures just above freezing, but they can't freeze. If they do freeze, they die.

In Alaska, being cool is not good enough. Here, the ground freezes and so do the frogs - but they don't die. Alaska's frog, the wood frog, has a different strategy. When ice crystals begin to form on a wood frog's skin as the fall days cool below freezing, it triggers an adrenalin response, much like the fight or flight response in mammals. The wood frog responds by flooding its bloodstream with glucose - blood sugar. This blood sugar acts as an antifreeze that protects the cells, even though most of the water in the frogs body outside the cells does freeze. In a person, a blood sugar level of 90 micrograms per 100 milliliters of blood is normal. In freezing wood frogs, the blood sugar level is 450 times higher, which would kill a person many times over. The frogs survive in part because their metabolism has essentially shut down.

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Frogs (mp3, Transcript)


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The spring chorus of frogs is a familiar sound in many parts of the United States. Frogs prefer warmer climates, and the variety decreases as you head north. There are 30 species of frogs in Mississippi, 14 species of frogs in Oregon, and just two in Alaska. Alaska is home to the Columbia spotted frog, found only in a few parts of Southeast, and the wood frog, found from Southeast north to the Arctic.

The wood frog is the northernmost frog in the world. It is one of the most freeze tolerant species on Earth; it has the amazing ability to freeze solid and thaw out as temperatures warm in the spring. Wood frogs hibernate in shallow bowl-shaped depressions under a layer of dead vegetation (duff), with snow cover providing additional insulation.

At the onset of freezing temperatures, wood frogs begin pumping much of the water out their cells and organs and into extracellular spaces and body cavities. At the same time, they pump large amounts of glucose - a sugar created in the liver - into their cells. The syrupy glucose solution inside the cells serves as a cryoprotectant - essentially an antifreeze - protecting the cells from freezing and from drying out. As the temperature drops, ice fills the abdominal cavity and encases all the internal organs. Flat ice crystals form between layers of skin and muscle, and the eyes turn white because the lens and fluids freeze. Nearly 70% of the frog's total body water is converted to ice. The blood freezes, the heart stops beating, and all breathing and muscle movements cease.

In April and May, as ice begins to melt along the shores of ponds or lakes, the wood frogs thaw and re-animate.

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Funny River Fire (mp3, Transcript)


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Funny River Fire

A nice fire in the woodstove on a winter day is a welcome thing. A big wildland fire in summer is another. The Funny River Fire was the biggest fire in Alaska in 2014. Conditions were ideal in late May for a fire on the Kenai: low humidity of just 20 percent, a dry wind from the north, and an abundance of dry grass. By the time the human-caused fire was burned out, the burn encompassed almost 200,000 acres. Fish and Game biologist and forester Sue Rodman explains how and why the fire was so extensive.

"Most of the black spruce there were over 60 years old and they were prime for burning. They're 30 feet tall or more, they have limbs that go all the way to the ground, and the understory vegetation is cranberry and blueberry that burns really well."

Most trees are mostly water; the wood and bark weigh less than the water inside the tree. The moisture-to-weight ratio is 200 percent in most live trees, a cottonwood is 300 percent. In spruce the moisture to weight ratio is just 60 percent. There's a reason spruce makes good firewood.

"Spruce trees have less moisture in them when they're alive than most trees do when they're dead," Rodman said. "You combine that low moisture with the volatile contents in the sap and needles, and they burn great."

A 200,000 acre burn conjures the image of a moonscape, but it's not all burned. Different forest types, wet areas, creek and rivers and terrain features create a mosaic of burned and unburned areas, which is good for wildlife and helps regeneration.

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Garden Spider (mp3)


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How Big is that Animal? (mp3, Transcript)


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How big is that animal?

On a warm summer day a man is walking through a wooded suburban neighborhood north of Juneau. He catches a glimpse of a big yellow animal with a long tail, running across the road. He reports a possible cougar sighting to Fish and Game, but on further investigation, it turns out to be a neighborhood dog.

Derek Broman is a carnivore biologist in Oregon and frequently investigates cougar reports in a state that actually has cougars. He offered some advice on what to do if you see an unusual animal. A key point is judging the animal's real size.

Broman said scale can be confusing, and people mistake housecats for mountain lions. People have reported black panthers, but there has never been a melanistic cougar documented in Oregon, he said. "You need an indicator of scale," he said. "You see something walking through the grass in a field, go out and see how tall the grass is. You might think it's two feet tall and it's three inches tall.

"Even hunters do it - they think a bear is huge and come up on it and it's a yearling. If something ran across the road, stop and look at how tall the vegetation is beside the road. Is that leaf there the size of your hand or bigger than your head?"

Broman said dogs are often the cause of false alarms. Color is often the first thing people note, and that can be a dog, a deer or even a housecat.

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Invisible Sounds (mp3)


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Izembeck Refuge (mp3)


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Land Bridge (mp3, Transcript)


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Land bridge

The Bering land bridge is well-known in Alaska. In the ice age, this broad corridor connected Alaska with Siberia, allowing the migration of animals such as bison, mastadons, wolves, bears and people.

But another land bridge existed in North America before the ice age, that had a profound impact on wildlife and ecosystems - and that land bridge still exists. It's the Isthmus of Panama.

After the time of the dinosaurs ended, about 65 million years ago, mammals evolved separately on the landmasses that were to become North and South America. Just three million years ago, very recent in geologic time, plate techtonics brought the continents together. The connection of the two great land masses profoundly altered ocean currents in both the Atlantic and the Pacific, changing the climate of the western hemisphere. It also allowed animals to move north and south. Cats were unknown in South America, and the big saber-toothed cats of the Pliocene period found good hunting in the virgin territory of South America. Bears also moved from North America to the southern continent, as did the North American camel species that evolved into llamas and alpacas. Other animals came north. From South America came armadillos, opossums and porcupines. The ancestors of Alaska's porcupines migrated north to Alaska from South America three million years ago, crossing the narrow land bridge at the Isthmus of Panama.

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Mosquito (mp3, Transcript)


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On a hike to Windfall Lake north of Juneau, we take a break in a swampy lowland. Mosquitoes are thick, and we are wearing repellent, and headnets, and full-coverage clothing. Some people claim they are especially targeted by mosquitoes, and it's possible - mosquitoes are attracted by a combination of factors - carbon dioxide in our exhaled breath, warmth, moisture and even darker colors. Someone who is sweating hard and breathing harder is a prime target.

Alaska is home to more than 30 species of mosquito, including the relatively large snow mosquito, which emerges early and can be active when there is still snow on the ground. In all cases it is only the female that bites, requiring a bit of blood nourishment to lay eggs. That tiny amount of blood adds up when millions of mosquitoes are swarming. On the summer tundra of northern Alaska, a caribou can lose up to a pint of blood a day to the hordes.

Mosquitoes can be bad in Alaska, but fortunately they are not dangerous, as they can be in warmer parts of the world where mosquitoes transmit diseases like malaria - caused by a tiny parasite that lives in the mosquito. A mosquito only lives about a month. Alaska's relatively short summers don't provide enough time for the life cycle of the plasmodium parasites and the mosquitos to reach fruition and transmit the disease.

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Muskeg (mp3, Transcript)


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A swainson's thrush sings on a summer evening from the top of a pine tree in a Southeast Alaska muskeg. Alaska's boggy muskegs are home to a variety of birds and animals, and unusual plants like the carnivorous sundew. But muskegs are not unique to Alaska. They are a type of wetland found in cool climates, closely related to landscapes elsewhere known as moors, peatlands, and bogs. Muskeg is a Cree word and is the term most commonly used in Canada and Alaska. Muskeg in Siberia is also called bogland.

Muskeg has the water table near the surface. Water flowing out of a muskeg is brown because of tannins dissolved in the water. Plant growth is slow because the soil is not very fertile, and decay is even slower because of the saturated, acidic, anaerobic soil. Sphagnum moss thrives in muskeg, and much of the soil is dead moss. Sphagnum moss can hold up to 30 times its own weight in water, allowing the spongy wet muskeg to form on sloping ground. The spongy mass of muskeg soil is known as peat, and peat accumulates and in some areas can be very deep.

Peat is harvested and dried as an important source of fuel in parts of the world. Peat moss, as dried sphagnum is often called, is used as a soil conditioner, as a packing material for shipping seeds and plants, and is used in the mushroom growing industry for cultivating mushrooms.

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No Snakes in Alaska (mp3, Transcript)


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No snakes in Alaska

On a spring vacation fishing trip to the Natchez River in Texas, my friends and I spot a big water moccasin on a clump of brush on the riverbank. Kevin warns a couple passing in a small boat: Quote. By the end of the afternoon we've seen five water moccasins, a copperhead and a red bellied water snake, the only non-venomous snake of the day. For an Alaskan, it's a big day for snakes.

There are 15 subspecies of venomous snakes in Texas, in four groups -water moccasins, also called cottonmouths, copperheads, rattlesnakes and coral snakes. Alaska is famous for its complete absence of snakes, something most people - especially people from venomous snake country - fully appreciate. There are no lizards, freshwater turtles, or snakes in Alaska. The only reptiles in Alaska are rare sightings of sea turtles.

Texas is home to 76 species of snakes, more than any other state. As you head north, snakes and reptiles are less abundant. Oregon is home to 16 snake species.

Texas straddles the west and the south, with the wet climate in the east favored by coral snakes and the dry climate in the west favored by rattlesnakes. There are dozens of turtle and lizard species, and even alligators.

All reptiles are in some form of cold-bloodedness, and although there are a variety of metabolic strategies used by cold-blooded animals, reptiles tend to rely on solar energy for heat.

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Parasites and Pets (mp3, Transcript)


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Parasites and pets

A successful hunter is cutting and wrapping moose meat in the garage. She's trimming meat and setting aside some scraps and bones for the dog, which begs for the ocassional tidbit. This hunter may be giving her dog more than scraps - she might well be passing on parasites.

Dogs are canids, related to Alaska's wild canids like foxes, coyotes and wolves. Dogs can get all the diseases and parasites that spread between game animals like moose and caribou and their natural canid predators and scavengers. Bacteria like brucellosis and tularemia, round worms like trichinella, and a variety of tapeworms, can all be transmitted to dogs that eat raw game meat. Tapeworm cysts occur in meat, and in the liver and lungs of game animals.

It's not legal to feed game meat to pets or livestock. However, the skin, heads, bones and organs may legally be fed to pets or livestock after all the edible meat is salvaged. Freezing kills some parasites, but trichinella in Alaska - which is common in bear meat - is a parasite adapted to the north and is not killed by freezing. Scraps left over after all meat is legally salvaged should be cooked before it is fed to pets.

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Riparian Corridor (mp3, Transcript)


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Riparian Corridor

Dappled sunlight filters through the dense vegetation bordering an Alaska stream. This streamside zone is known as the riparian corridor, and it's rich with life - songbirds nesting and singing, small mammals feeding and hiding, and moose and bears following stream side trails.

Riparian corridors include the streambank, floodplain, and distinct riparian vegetation transitioning into upland vegetation as the land rises away from the river. The width depends size of the river and the surrounding terrain and can vary from tens of feet to many miles, often encompassing side channels and wetlands. Riparian corridors are more productive than the surrounding lands due to the moisture and nutrients, and the abundance of vegetation and animal life. This benefits fish because these nutrients are the basis of the food chain. The riparian corridor moderates stream temperatures, filters sediments from surface runoff, slows flood waters, buffers storm runoff, and reduces peak flows during rainstorms.

Plant roots in the riparian help hold soil in place, like rebar strengthening concrete, and prevents or slows erosion of the river bank during high flows. Vegetation also adds roughness to the banks and floodplain, slowing water velocity during floods and reducing its power to erode. Slowing the flow of floodwater allows suspended sediments to settle out deposit silt and sand along floodplain, adding nutrients to the soil, and growing and strengthening the streambank.

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Rollerchopping (mp3, Transcript)


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On a winter day in January of 2016, a bulldozer is plowing through a stand of aspen near Tok in Interior Alaska. It's pulling a big rolling drum studded with chopping blades. The dozer blade snaps the trees off at the base and the roller chopper breaks them up.

Aspen is a botanical Phoenix, flourishing in the wake of destruction. The lush growth that emerges after an aspen stand is burned or crushed is ideal for moose and grouse, and that benefits moose and grouse hunters.

Fish and Game has partnered with the state division of forestry and the Ruffed Grouse Society on this habitat enhancement project near Tok, and this winter more than 250 acres were treated. It's the second year of a five-year project that aims to treat about 750 acres. This winter they treated about 16 acres per day, about twice what they did last year. That's with a D-5 and a D-6 cat, each pulling a roller chopper, covering about eight acres per machine each day.

Winter is the best time for the work and produces the greatest return. A temperature range from fifteen-below to zero is ideal. The green stems break easily when it's cold, and with the root base frozen in the ground. In winter, when the trees are dormant, all the nutrients are in the root system, and the root system can put it all back into the new growth the next growing season. The frozen ground also protects the root base from being torn up and crushed.

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Salamander (mp3, Transcript)


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A bear cub is foraging along the bank of the Taku River in Southeast Alaska. He rolls over a log, revealing a four-inch long dark brown salamander nestled in the mud. He gives it a sniff, but this is a long toed salamander, and it secretes noxious proteins in its moist skin, a defense that makes it taste bad. Long toed salamanders are also capable of autotomy - its tail can break off and wiggle, creating a squirming decoy while the salamander slinks away. That's not required in this case, the bear cub, deciding the tiny morsel is not very appealing, ambles on and catches up to his mother, and the salamander burrows into the mud until it's once again hidden.

Salamanders are found around the Taku and the Stikine Rivers in Southeast, where they presumably made their way down from British Columbia. Newts are more common although only one species, the rough-skin newt, is found in Alaska, and also, only in Southeast.

Long toed salamanders are true to their name, and the fourth toe on each back foot is noticeably longer. As adults, they're rarely seen because they live a subterranean lifestyle, digging and feeding on insects and worms in forest soils, decaying logs, and rock fissures. As amphibians, they're also aquatic and eat tadpoles and small fish. They can live 10 years, but rarely get bigger than about five inches long.

Like the tadpoles of frogs and toads, salamanders have a larval stage that is completely aquatic, with external gills. As the larvae matures and reaches about two inches in length, their limbs grow, then toes grow on their feet, their gills are resorbed, and then metamorphose into a small adult.

In warmer climates long toed salamanders are active all winter long. However, during the winter months in colder parts of its range, long-toed salamanders burrow underground and hibernate in clusters of a dozen or so individuals.

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Sea Turtles (mp3, Transcript)


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Sea Turtles in Alaska

Terrestrial and freshwater turtles do not occur in Alaska, but four species of sea turtles have been documented in Alaska's Gulf Coast waters. These are the leatherback sea turtle, the green sea turtle, the olive ridley sea turtle and the loggerhead sea turtle.

The Leatherback sea turtle is the world's largest turtle. Since 1960, there have been 19 documented sightings of these impressive reptiles. There have been 15 reports of green sea turtles. Sightings of the other two sea turtle species can be counted on one hand, just three sightings of olive ridleys and two sightings of loggerheads.

Leatherbacks can be eight feet long and weigh 1,500 pounds, but most are about half that size and weight. Green sea turtles average about three feet in length and weigh about 200 pounds.

Leatherback sea turtles feed almost exclusively on jellyfish. Leatherbacks have a mammal-like ability to maintain a high body temperature, about 80° F, independent of the temperature of the surrounding water. This may account for their occurrence in cold northern waters where jellyfish are seasonally abundant.

Marine turtles may migrate thousands of miles between their nesting and feeding grounds, and probably reach Alaska by way of the warm Japan Current and the North Pacific Current, which flow toward Southeast Alaska and then arc northwest across the Gulf of Alaska and then southwestward along the Aleutian chain.

The leatherback sea turtle is endangered throughout its range. All marine turtles are protected by the federal government.

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Shrimp Change Sex (mp3, Transcript)


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Shrimp change sex

After a day of salmon fishing, a boater in Southeast Alaska heads to a quiet bay for the evening. Before heading out in the morning, he set a string of shrimp pots off the mouth of a silty glacial river, and now he's hauling up those cage-like traps. He's caught a few dozen coonstripe shrimp, delicious five-inch-long crustaceans.

Five species of pandalid shrimp are found in the cool waters off the coast of Alaska. Sidestripe and coonstripe shrimp are renowned for their sweet flavor. Pink shrimp are the foundation of the commercial trawl shrimp fishery in Alaska. Humpy shrimp range from Washington's Puget Sound to the Arctic coast of Alaska. Spot shrimp are the biggest shrimp in the North Pacific and are highly valued by commercial pot fishers and subsistence users alike.

Pandalid shrimp are among the relatively few animals that exhibit protandrous hermaphroditism. Each individual spends the early mature part of its life as a male and later transforms into a female for the balance of its lifetime. For example, a pink shrimp will typically mature sexually as a male, spawn one or more times, pass through a short transitional phase and subsequently mature and spawn as a female.

Shrimp spawn in the fall and the eggs incubate over the winter. In the spring the eggs hatch into planktonic, free-swimming larvae. By mid-summer, the larvae have undergone several molts, rapidly increasing in size after each molt. After the last larval molt the juvenile shrimp settles to the bottom. After a year or so, the juvenile molts and develops into a mature male and may spawn as a male for one or two seasons. Some juveniles, however, never mature into males; instead, they develop directly into females.

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Sneaky Snails (mp3)


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Spider (mp3, Transcript)


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A beautiful yellow orb spider hangs head-down in a platter size web fastened to a backyard playhouse in Anchorage. The playhouse belongs to a girl who appreciates this backyard insect predator; she and her mom have been watching this spider catch and eat bugs all summer. She's giant by Alaska spider standards, a member of the family Aranedea, brightly colored garden spiders considered beneficial because they eat garden pests.

Orb spiders go back to the time of dinosaurs. As flowering plants evolved and flourished during the cretaceous period, their insect pollenators thrived along with them, spreading across the planet. Orb spiders also flourished thanks to their amazing silk, a strong, elastic protein they spun into nets capable of sustaining the impact of flying prey. The orb-web is a frame of tough anchor lines overlaid with a sticky capture spiral, and the silks of orb-weaver spiders have exceptional mechanical properties. One strategy that helps - Orbicularian spiders tend to eat their web every day, re-spinning a fresh orb that's strong, sticky and clean.

Garden spiders generally live just one season, laying eggs in the fall, ensuring a new generation of spiderlings will disperse in the spring.

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Subnivian (mp3)


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Sundew (mp3, Transcript)


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On a sunny spring morning, the snow has finally melted from an Alaska muskeg, and the spongey green meadow is warming in the sunlight. Insects are beginning to buzz and flit, and an insect predator is here, silently hunting. Trapping is a more accurate term. Although this is a life and death drama playing out on the surface of this soggy meadow, it's a subtle one. The hunter is a sundew, the only carnivorous plant in Alaska.

There are about fifty carnivorous plants in the world, and two species are found in Alaska, the roundleaf and the narrowleaf sundews. They're found throughout the state in poorly drained areas like fens, wet meadows and muskegs, where plants have adapted to nutrient poor soil, or developed ways to supplement their nutritional needs. Alaskans hiking through such areas have likely stepped on or over these sundews. A close look at the moss and vegetation underfoot would reveal a low-growing, palm-size plant with fingernail-size leaves. Each leaf is covered with tiny hairs, glands actually, each secreting a shiny, sweet droplet of goo that attracts and traps gnats and mosquitoes. Once stuck to the gluey leaf, the insect's body is absorbed into the plant.

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The Deadliest Animal (mp3, Transcript)


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The deadliest animal

When people think of dangerous animals in Alaska, bears usually come to mind. When a bear hurts somebody, it's big news, but it's actually pretty rare. The deadliest animal in the world is common in Alaska, but it's not deadly here in the north. It's the mosquito.

Alaska is famous for mosquitoes, and most Alaskans have experienced a relentless, maddening horde of mosquitoes on a summertime fishing or camping trip. But in tropical countries where mosquitoes carry diseases like malaria, dengue fever, and yellow fever, mosquitoes are deadly. There were almost 200 million cases of malaria in 2013, and between a half-million and a million deaths. In one sense, it's not the mosquito that kills, but a protozoan parasite the mosquitoes carry that causes malaria. But mosquitoes' role in delivering the disease-causing protozoan to people makes it a killer.

Why don't Alaska mosquitoes carry malaria? The main limiting factor for the transmission of malaria is temperature. It has to be warm enough for that protozoan parasite to complete its life cycle. At 77 degrees, the parasite can complete its life cycle in a little less than a month. At temperatures below 68 degrees, the parasite can't complete its life cycle within the life span of the adult mosquito.

While Alaska is not at risk for malaria, it's not strictly a tropical disease. A malaria epidemic killed thousands of people in Oregon in the 1830s.

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Ticks (mp3, Transcript)


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A couple of kids are playing with their neighbor's dog, a two-year-old yellow lab. They notice a grey bump the size of a blueberry by his ear, and take a closer look. It's a tick. Ticks, small blood-sucking arachnid parasites, are not well-known in Alaska. One species, generally found on squirrels and hares, is fairly common and native to the state, but biologists are concerned about the introduction of non-native ticks to Alaska.

If you find a tick on your pet, or a person, you can remove it yourself or take your pet to a vet. It's easy to remove a tick. Don't put oil or solvents on the tick, and definitely do not apply heat to it. Just pull it out with tweezers. Use fine pointed tweezers, grasp the tick close to the skin, apply firm, steady tension straight out and in just a few seconds, it will release. Don't squash it. Wash up afterward.

Biologists are studying ticks to determine if non-native ticks are becoming established in Alaska; they're also testing ticks to monitor the potential introduction of tick-borne diseases to Alaska. You can call your local Fish and Game office if you have any questions about ticks you find on pets, people or wildlife.

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Timberline (mp3, Transcript)


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Take a look at almost any mountain in Alaska and you'll see trees growing on the lower reaches. As you look higher upslope you see that trees stop growing along a fairly distinct line - the timberline. The timberline is a visible boundary between the forest and the alpine. Trees might thrive on lower slopes, but at the boundary, even Alaska's hardy spruce and mountain hemlocks struggle to survive. What determines the timberline? The average temperature in July.

Even the hardiest evergreens need two months of warm weather to flower, pollinate and produce seeds. If the temperature in July averages 50 degrees, there will be enough warm weather for trees to reproduce. Cooler average temperatures mean trees can't complete their life cycle. Growth slows. At and above the timberline other factors conspire to make life hard or impossible for trees. Strong winter winds carry sharp ice crystals that blast and prune trees. Extreme winter cold freezes the trees, causing cracking and splitting. In winter, trees also battle dehydration. The ground around the roots freezes and water is unavailable. Dehydration kills the tops of the trees, and keeps the timberline trees low growing.

Above the timberline, alpine plants have adapted to mountain conditions and small perennials like dwarf willow and dryas make the most of the short growing season.

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Toads and Tadpoles (mp3, Transcript)


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Toads and Tadpoles

On a sunny morning in late July near Haines in Southeast Alaska, four kids have discovered a small stream full of tadpoles. Thousands of black tadpoles are milling about or resting in the shallow, sun-warmed water. These aren't frogs, they're toads - Western Toads, the only species of toad in Alaska.

These toad tadpoles are about the size of a dime, with a short tail. They're growing fast, feeding on aquatic plants and algae. Adult toads eat insects, worms, spiders and slugs, but tadpoles are herbivores. These tadpoles hatched from eggs laid in late April or early May. Breeding is highly synchronous, meaning all the toads in an area mate and lay eggs in just a few days. The eggs hatch in about a week, and the tadpoles grow and develop for two or three months in the summer. During that time, they are vulnerable predators like robins, sandpipers, yellowlegs, and killdeer and predaceous invertebrates like diving beetles and dragonfly larvae. If they escape these tadpole predators, in a few weeks these tadpoles will undergo changes - their skin hardens, they develop legs, and metamorphose into toadlets, which look like tiny adults.

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Troll Removal (mp3, Transcript)


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Troll removal

Fish and Game biologists get some strange calls. Once, in Kenai, a mountain goat wandered into someone's house and garage and wouldn't leave. Biologists were called in to tranquilize and capture the goat, which was released back into the wild.

Sometimes bears get a little too accustomed to life in and around cities and need to be relocated. But this spring, biologist Kathy Hocker worked on the strangest relocation in her career.

"Yeah, we started getting these calls, it was living under a bridge out the road. Normally, we're pretty live and let live about these things, but it was starting to bother people, coming out, demanding a toll to let people cross, even threatening to eat some people up."

It was a Norwegian troll, the short, hairy kind. Norwegian wildlife biologist and troll expert was brought in from Oslo to help with the identification, capture and transport.

"Ja, we have seen this before. Usually when this happens they are coming down out of the mountains to capture a princess or something like that. What's really strange is this troll is so far from Norway. Maybe someone was keeping him as a pet and released him, but I doubt that, since they do not make very good pets. It might be connected to global warming or something..."

After equipping the troll with a gps collar, he was released east of the Sun and west of the Moon.

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Turtles (mp3)


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Visiting Sea Turtle (mp3, Transcript)


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Visiting Sea turtle

Fishermen aboard a purse seiner just south of Prince of Wales Island encountered an unusual reptile in Alaska waters as they were setting their net in May of 2020 - a green sea turtle.

The crew was concerned the turtle might become entangled in their seine net and brought it on board temporarily before releasing it unharmed. They guessed the turtle weighed about 40 pounds - since green sea turtles can weigh up to 350 pounds, and this animal would still be considered a juvenile.

A sea turtle biologist said the turtle most likely hatched on a beach in southern Mexico and headed out to sea as a baby. He said most adult green sea turtles live close to shore but some remain in the open ocean their entire lives.

Prevailing currents along the west coast run south, but further offshore currents can run northerly, enabling a turtle like this to passively drift with the currents over time, from Mexico into Southeast Alaska waters. Following its brief encounter with the friendly seiners, the near-shore currents would likely move it south to more suitable warmer habitat. Since 1963, 21 green sea turtles have been documented in Alaska waters, some as far north as Homer and Kodiak. All told, other Alaska sea turtle sightings include 19 leatherback sea turtles, and a few olive ridleys and loggerheads.

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White for Winter (mp3, Transcript)


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White for winter

A white coat against winter snow is the next best thing to invisibility, and that's important for predators and prey. Arctic foxes are both. They hunt voles and lemmings, and in the high Arctic they trail after polar bears and glean scraps from their kills. Bears, snowy owls and golden eagles eat foxes given the chance, and the foxes' white winter coat helps them to hunt and hide.

Hair is white because it lacks pigment. Animals have cells that produce melanin, the natural pigment that gives hair, skin and eyes color. When the fox is shedding its summer coat and growing its white coat in the fall, melanin production is shut off and the fur comes in without pigment.

Daylight, not cold weather, triggers seasonal shedding and hair growth. Animals register changes in the photoperiod - the hours of daylight - which spurs the secretion of hormones such as prolactin and melatonin. This has been duplicated in indoor experiments - shortening the photoperiod induces hormone production and the growth of the winter coat, and lengthening it simulates the springtime phase.

Come spring, that white coat is a liability, and the Arctic fox switches to a more appropriately colored coat.

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Woolly Bear Caterpillar (mp3, Transcript)


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Woolly bear caterpillars

Hiking a Juneau trail on a sunny August day we encounter a fat, inch-long fuzzy black and orange caterpillar. Within an hour we've seen more than a dozen. For a few weeks in late summer, these woolly bear caterpillars are everywhere. A little research reveals that they are not more abundant than normal, just more noticeable. There are two reasons.

Woolly bear caterpillars are the final larval stage of the spotted tussock moth, part of a larger group known as tiger moths. The caterpillar hatches from an egg, and the tussock moth caterpillar goes through five stages as it grows, these stages are called instars. The black and orange banded caterpillar is the fifth and final instar, and the only one with this distinct coloration. So these small black caterpillars don't look like woolly bears most of the time. In this final instar, the caterpillars are preparing to overwinter in a cocoon. They're on the move, looking for a good place, so they attract attention. Once the cocoon is built they will pupate inside and overwinter. Next spring they will emerge as adults.

In most temperate climates, caterpillars become moths within months of hatching, but in the north the summers are short, so the Woolly Bear must feed for several summers, freezing each winter before finally pupating. Some are known to live through as many as 14 winters.

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