Archive for June, 2015


I was excited to start my first day of real “field observation” with the webcams set up along the Brooks River at Katmai National Park, to kick off my brown bear watching project. I had checked out all of the available webcams casually, to make sure they would work, primarily to ensure good enough resolution for me to be able to rely on them for field observation. But I had overlooked the time difference between my home in New Orleans and the “bearcams” in Alaska. So the first time I had set aside for field observations, it was too early in the morning Alaska time for me to see the bears very well. Still, I was able to get a few minutes of bear-watching in before I had to go about the rest of my day.

Screen Shot 2015-07-07 at 11.12.25 AMThe live feed at Brooks Falls was the only camera with any bear activity at the time I checked in this morning. I saw two bears at the falls, at spots the park refers to as “the far pool” and “the jacuzzi”. Both were there for only a few moments. The one at the far pool (background of this image) was there when I turned on the feed, though it took me time to realize the shape was that of a bear and not a rock, as it wasn’t moving very much. Clearly from this video I was unable to tell if the bears were male or female, or any other distinguishing features, so I will call them Bear A (far pool) and Bear B (jacuzzi). Bear A was standing on top of some of the rocks, not in the water, and turned around a few times toward the falls and then looking downstream, and then turned back again. Screen Shot 2015-07-07 at 11.11.53 AM

I then saw the second bear (Bear B) come in from the bottom right side of the screen. Bear B settled at the spot known as the jacuzzi (foreground area, near the base of where the falls hit). The bear kept looking around, including behind/downstream of their location, the entire time, rather than keeping their eyes on the falls. I don’t believe it successfully caught any fish during the time I was watching, and it only stayed in that spot for maybe 5-6 minutes before turning and walking back off-screen, slightly downstream and toward the bank of the river again.

Screen Shot 2015-07-07 at 11.04.06 AMBear A stayed was at the far pool the entire time, but because of the darkness it was difficult to keep track of it as it moved around in that area, so I was not able to tell if it was able to catch any fish or not.

So far it’s been difficult to capture any real information other than a) this is not the best time of day for me to try to watch the bears via video; and b) the bears seem willing to share some of the space at the falls with other bears, though I don’t have enough information about the bears to know whether they share with members of the same or opposite sex, age differences, or how common this is overall. I also know that the physical observation area for visiting tourists is near or at the same location as the camera, so it is possible that the bear fishing at the far pool is more wary of human interaction than the bear fishing at the jacuzzi.

I found some additional information on the favored fishing spots at Brooks Falls in the Katmai National Park eBook Bears of Brooks River 2015.  They include a helpful diagram including the names of the spots I’ve mentioned, such as the jacuzzi, the far pool, and “the lip”, a spot on the top side of the falls, as favorite spots where the bears will sit to fish.

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To serve as an introduction to the species before I begin logging my own observation notes, here’s a brief overview of the brown bears found in Katmai National Park. Their scientific name is Ursus arctos; they are commonly known as both the brown bear and the grizzly bear. From what I’ve been able to tell so far, the difference between the two is somewhat arbitrary, and has more to do with where they’re found rather than an actual difference in genetics. Those bears found closer to the coasts and relying more heavily on fishing (such as the ones at Katmai), are known as brown bears, while those found further inland, and may have access to mountain goats, sheep, and moose, are more often known as grizzly bears, a subspecies of brown bears (Ursus arctos horribilis).

Geography & Habitat

Brown bears occur throughout Alaska except on islands south of Frederick Sound in southeast Alaska, west of Unimak in the Aleutian Chain, and Bering Sea islands. They also occur in Russia, northern China, northern Japan, Europe, western Canada, and in limited portions of the northwestern United States. (Source: Alaska Department of Fish & Game)

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Image Source: Alaska Department of Fish & Game

Physical Description

Katmai’s brown bears are some of the largest bears in the world. They can stand 3-5 feet (.9-1.5 m) at the shoulder and measure 7-10 (2.1-3 m) feet in length. Most adult males typically weigh 600-900 pounds (272-408 kg) in mid-summer. By October and November, large adult males can weigh well over 1000 pounds (454 kg). Adult females average about 1/3 less in weight than adult males. (Source: National Park Service)

Brown bears in the wild can live for 20 to 30 years, although most brown bears die in their first few years of life. In captivity, brown bears have been known to live up to 50 years. (Wilson and Ruff, 1999)
Fur is usually dark brown, but varies from cream and light blonde to almost black. Individuals in the Rocky Mountains have long hairs along the shoulders and back which are frosted with white, giving a grizzled appearance, hence the common name grizzly bear in that region. Brown bears are extremely strong and have good endurance; they can kill a cow with one blow, outrun a horse, outswim an Olympian, and drag a dead elk uphill.(Source: Animal Diversity Web, University of Michigan Museum of Zoology)

Mating & Reproduction

Brown bears mature sexually between 4-6 years of age, but continue growing until 10-11 years old. Bears have been known to live and reproduce in Yellowstone Park at 25 years of age, and potential lifespan in captivity is as great as 50 years. (Wilson and Ruff, 1999)

Female brown bears copulate with multiple males during estrus, which lasts 10 to 30 days. Males may fight over females and guard them for 1 to 3 weeks. Female receptivity is probably communicated by scent marking throughout her territory. (Wilson and Ruff, 1999

The brown bear mating system is polygynandrous (promiscuous), and takes place from May to July. Fertilized eggs develop to the blastocyst stage, after which implantation in the uterus is delayed. The blastocyst becomes implanted approximately 5 months after mating, usually in November when the female has entered her winter sleep. A 6 to 8 week gestation follows, with births occurring from January to March (usually while the female is still in hibernation). Total gestation time, including pre-implantation, ranges from 180 to 266 days. Females remain in estrus throughout the breeding season until mating occurs and do not ovulate again for at least 2 (usually 3 or 4) years after giving birth. Two to three offspring are generally born per litter. (Source: Animal Diversity Web, University of Michigan Museum of Zoology)

Cubs are born in the den during January and February. Twins are most common, but litter sizes can range from 1 to 4. When the cubs emerge in June, they may weigh up to 15 lbs (7 kg) and they actively explore their world under the constant supervision of their mothers. Mothers can be furiously protective of cubs, however less than half of the cubs survive. Families typically stay together for 2 or 3 years and after separation female cubs tend to stay near where they were raised while males go farther afield. Most brown bears are sexually mature at 5 years old; however females often do not successfully produce a litter until later. The mating season is in the spring (May to July) and they are serial monogamous (have one mate at a time, but several each year). The oldest brown bear in Alaska was a 39 year old female, while the oldest male was 38. (Source: Alaska Department of Fish & Game)

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Image Source: National Park Service

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The brown bears I’m observing for my field notes assignment are found in Katmai National Park & Reserve in Alaska, USA. According to the Katmai website, there are approximately 2,200 brown bears inhabiting the Park, and, in their words: “As many bear populations around the world decline, Katmai provides some of the few remaining unaltered habitats for these amazing creatures. At Katmai, scientists are able to study bears in their natural habitat, visitors are able to enjoy unparalleled viewing opportunities, and the bears are able to continue their life cycle largely undisturbed.”

For a geographical context, here’s a series of sequentially more zoomed-in maps (via Google Maps) of the location of Katmai National Park & Reserve in Alaska, the Brooks River & Falls, and the corresponding live webcams which allow for Internet-wide viewing of brown bears at Katmai.

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