Injured Nose Bears

It’s not uncommon to see bears with open wounds and distinctive scars, like bear 83 who seems to repeatedly get injured.

crescent-shaped wound on bear rump.

Photo of 83’s wound from 2015. In 2016, his rump was injured again courtesy of bear 747.

Wounds and the subsequent scars are useful when identifying Brooks River’s bears, since each bear carries a unique suite of them. 83 now sports a large scar on his rump.

Bear standing in white water.

The lump on 83’s rump marks the scar from his 2015 injury.

Sometimes though, we see bears with scars or injuries that may be more than superficial, perhaps impacting the sense they rely on most.

On September 13, 2017, a bear with a large, distinctive scar on his left shoulder was photographed at Brooks River.

1stnite2

Photo courtesy of Lee (aka RiverPA) via Flickr.

Most distinctively, his nose is split.

1stnite

Photo courtesy of Lee (aka RiverPA) via Flickr.

This appears to be an old injury and when I saw these photos I wondered have we seen this bear before?

In 2010 and 2011, a subadult bear with a torn nostril was seen at Brooks River. Bear 253 was a young subadult at the time, but Katmai’s bear monitor was not able to determine its sex. Its nose was most likely injured in 2010 as photos from 2011 show some healing.

 

 

253 probably isn’t the unidentified male photographed with the nose injury this past September though. 253’s muzzle is long and somewhat pointed while the male bear’s muzzle is blockier in shape. The nose injury on the male bear also seems more symmetrical than 253’s.

Would injuries like these impair these bears’ sense of smell? Perhaps, especially if it reduced the surface area inside the nose where scent can be detected.

Bears have a legendary sense of smell. The inside of their nose is filled with many turbinals, a complex scaffold of paper-thin bones. Humans have turbinal bones too, just far less than ursids. In black bears, for example, these bones greatly increase the surface area inside the nasal cavity, providing 100 times more nasal mucosa, or mucous membranes, than humans. More tangibly, if the area of muscous membranes inside the human nose equals the area of your typical postage stamp, then the area covered by mucous membranes inside the black bear nose covers an 8.5 x 11” sheet of office paper. On the surface of the membranes are millions and millions of scent detecting cells. In short, bears live in a world of odors we can scarcely imagine.

Like human eyesight, hearing, and smell, the strength of these senses likely varies in bears. Some bears may have worse eyesight than others (although it’s a myth that bears have poor eyesight; they don’t). Others may have worse hearing. In the case of bears with injured noses, they may not be able to smell as well as their cohorts. (It’s important to note that in the case of 253 and the adult male seen this past September, the injury to their nose may not be deep enough to affect the turbinals.)

If bears are anything though, they are tough survivalists. A nose injury could impose a severe disability on them, but that won’t stop them from doing whatever they need to do to survive.

My Trip to Brooks Camp 2017: Day Four

Rain falling on a tent is the least motivating sound in the world and I heard it off and on through my last night in the Brooks Camp Campground. But by dawn, the rain nearly ceased and since this was my last morning to watch bears, I wasn’t about to let some drizzle get in the way of bear watching.

First, I had to get to the river. The campground is set almost a half-mile from the mouth of Brooks River. The walk between is easy enough, mostly flat and over crushed gravel trails, unless bears get in the way. After exiting the campground’s electric fence (5,000 volts of shock value), I stepped on to the beach to check if it was free of bears.

The trail to and from the campground parallels the beach, a place bears utilize frequently as a travel corridor or a place to rest. When bears are on the beach they are generally too close to the campground trail for it to be used. That morning, in the dim blue-gray light of an overcast dawn, I could see one bear sleeping between the visitor center and me. Giving this bear space was simple enough, all I had to do was swing through the forest and follow the faint trace of the waterline that ran to the campground. The risk in this plan though was the limited visibility in the forest. I moved slowly, watching and listening carefully for bears. The few belly holes along the route were empty and I safely reached the main trail with only a few moments lost.

At the river mouth, plenty of bears were active. 409 and her yearlings fished near the bridge and 410 stood still on the spit when a new family of bears appeared, one that I hadn’t yet seen in person. It was 435 Holly and her two very plump spring cubs.

bears standing on edge of lake with mountains in background

435 Holly and her two spring cubs stand near 410 on the spit at the mouth of Brooks River.

Crossing the river wasn’t as straightforward as the previous morning though as 409 and her two yearlings fished within a few yards of the bridge. As the family slowly made their way downstream, I prepared to speed walk across the bridge when the opportunity arrived. Just as 409 and her cubs waded far enough downstream of the bridge (more than 50 yards) I crossed quickly, and just in the nick of time. As soon as I reached the lower river platform, 854 and her cubs appeared on the Corner where I was standing.

Photo opportunities are limited with my durable but optically limited waterproof camera. Still, over the next 150 minutes, I watch 14 different bears (23 counting dependent offspring) using the lower Brooks River.

879_09062017

 Bear 879

 

bears in water near grassy marsh

854 Divot and her yearling cubs

two bears in water

708 Amelia and one of her 2.5 year-old cubs.

group of 11 black and white magpies in grass

Magpie convention

With my time at Brooks Camp running low, I ventured to the falls for one last look at the largest of the river’s bears. 32 Chunk, 151, 474, 480 Otis, and 747 round out the adult male roster this morning. When 747 sees 474 walk upriver, 747 directly approached 474. Both of the palindromic-numbered bears began to cowboy walk and mark trees, 474 on the shore near the platform and 747 on the island downstream of the falls. When 474 moved behind the platform, likely as a subtle move to avoid 747, the larger 747 marked the same tree and urinated in the same places as 474. Out of the water, 747’s true size is revealed. He’s a giant of a bear, far fatter and larger than any other on the river.

Bears use scent marking and body posturing to communicate their relative level of dominance. This morning, 474’s avoidance of 747 and 747’s subsequent scent marking of the same spots indicate 747 was the dominant bear, which is not surprising based on his gigantic proportions.

Before I left the falls for the final time (this year at least), I watched a young subadult bear fish the lip. She appeared well practiced in this spot. Bears rarely fish the lip of the falls in late summer, a time when nearly all salmon have reached their spawning site and lack the energy reserves or motivation to surmount the falls. The abundance of silver salmon in the river this year, however, allowed her to exploit this fishing spot during a time when it usually wouldn’t be worth visiting.

bear standing on edge of waterfall

This young subadult has fished the lip of Brooks Falls often recently. While bearcam viewers have speculated she might be one of 402’s emancipated cubs, this bear looked too big for a 2.5 year-old.

I encountered no significant delays on my return to the lodge to check in for my flight out. Lots of bears milled around the lower river, but I remained on the beach in front of the lodge to sit and watch 435 Holly and her cubs rest nearby.

bear family resting on beach

435 Holly and spring cubs

Brooks River is a special place, unique among national parks, and I felt fortunate to spend time there once again even if the visit was too short.

My Trip to Brooks Camp 2017: Day Three

When you enjoy watching wildlife as much as me, you don’t want to waste time with biological tasks like sleeping. Still, sleep is a necessity and I can’t watch bears in the dark. After a reasonably restful night, I woke before sunrise and left the campground when there was just enough light for me to see without a headlamp or flashlight. This would be my last full day at Brooks River in 2017 and intended to make the most of it.

Related:
My Trip to Brooks Camp 2017: Day One
My Trip to Brooks Camp 2017: Day Two

Early morning hours at Brooks River are generally quiet. Planes haven’t arrived and most people are either sleeping or focused on breakfast. The dominant sound at this hour tends to be the cry of glaucous-winged gulls.

Bears like early morning meals just as much as people, and I fully expected to find bears too close to the trail or bridge for me to reach the relative safety of the lower river wildlife viewing platform. Luckily, the corridor from the lodge to the bridge and the platform was clear before 7 a.m. In a short while, however, bears filled the void and for much of the rest of the day the bridge would remain closed to people.

When I first reached the platform, only 409 Beadnose and her yearlings were visible. Her cubs behaved quite independently, catching most of their own salmon. Yet they remained prone to begging food from their mother and bawling when they want to nurse. Two subadults entered the river upstream of the platform. 410 made the most of her chance for breakfast, eating at least five salmon carcasses in a half hour. It was still too dark for my point-and-shoot camera to take clear photos, so I sat back, watched, and took notes.

409, her cubs, and two young subadult bears all eventually wandered toward the river mouth and the beach in front of the lodge, allowing more people to cross the bridge. As the platform got noisier, I decided it’s a good time to wander to Brooks Falls.

The walk to the falls is quiet and uneventful, but bears used the trail just moments before. Foam clung to the surface of a large puddle of urine and bright red, relatively undigested lingonberries polka dot the surface of a fresh pile of scat.

red berries in bear scat

Even with the high abundance of salmon, bears were still feeding on berries.

The falls platform was empty when I arrived and no one else arrived for the next hour as bears remained too close to the bridge for people to cross. Within my experience at Brooks Camp, it’s rare to have the falls platform to yourself when bears are around.

view of river bordered by forest

I quickly forgot about being alone though as bears were quite active. 410 had made her way from the lower river to the falls where she fished her normal spot in the far pool. 68 was giving it a shot in the jacuzzi. Both bears ignored each other and remained separated by about 30 yards. When 747 arrived 68 quickly moves out of the jacuzzi to make way for the larger bear.

After 747 decided to push the other bears around, 503 appeared in the far pool. While 747 is absolutely the largest bear at Brooks River, I was shocked at 503’s size. He’s not particularly fat, but’s he’s very big for his age. Bears grow quickly yet I don’t recall ever seeing a 4.5 year-old brown bear as big as 503.

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503’s story is well documented here and here.

Returning to the lower river, I watched more subadult antics. Now after 10 a.m., the bridge had not yet opened because bears were consistently within 50 yards of it. Four to five subadult bears, all of which I saw the previous day, fished and played nearby.

409 Beadnose and her yearlings wandered toward the bridge from the lake to rest.

bear cub resting its head on its mother

Around 11:30 a.m., I contemplated crossing the bridge to eat lunch. At Brooks Camp food can only be eaten inside of buildings or at designated picnic areas. Possession of food, unless actively transporting it from one designated area to another, is also prohibited. With lots of bears in sight, I reasoned I could ignore my hunger pangs and eat later.

Upstream, 854 Divot and her yearlings scavenged for fish. Not yet having the opportunity to observe them much on this trip, I waited for them to fish their way downstream. Fall bears have a pattern though; they fish then sleep. Many human-habituated bears—especially 854 Divot, 409 Beadnose, 410, and 435 Holly—often choose to sleep near the trail between the lodge and the river. When that happens, the trail is usually closed until the bears wake and move on. I knew I risked a long delay getting to and fro if Divot and her cubs chose to sleep near the bridge or trail.

Which they did. At 12:10 p.m., Divot and cubs settled in for a nap on the bank just upstream of the floating bridge. With no alternative route around the bears, the bridge and trail were closed. There was nothing to do but wait. Bridge closures and Brooks Camp’s famous bear jams can be frustrating situations for people unaccustomed to them or too impatient for them, but bears need the habitat near the mouth of the river as much as they need the falls. To make a long story short (one I hope to tell in greater detail in the future) 854 slept in that spot for two hours and with many other bears fishing in the river, the bridge didn’t open for over three hours.

A half hour after crossing the bridge though and refreshed after a quick snack, I was back at the river when word of Otis’s arrival at Brooks Falls spread among the staff. Not knowing if I’d get another chance to see him before leaving the next day, I skipped bear viewing at the lower river to go to the falls, where I found 480 Otis as well as 68, 503, 719, 747, and an unidentified subadult.

bears fishing at waterfall

480 fishes in his office at Brooks Falls shortly after arriving. 747 sits in the water nearby.

Rain moved through later in the evening, but I still had one more morning of bear watching to enjoy before my flight out.

My Trip to Brooks Camp: Day Two

Due to strong winds, I was unable to reach Brooks Camp on time. The next morning, as instructed by Katmai Air, I arrived at their dock before 7 a.m. I was eager to get on the “first load.” Evidently everyone who didn’t reach Brooks Camp the previous day was told they’d be on the “first load,” which caused Katmai Air to deal with some cranky customers. (Not me, I might add, but I understood others’ frustration.)

aerial photo of lakes and mountain

Looking southwest toward Mount Brooks from the air.

Around 8:40 a.m., I arrived at Brooks Camp—or Lake Brooks to be exact. Winds out of the east were still too strong for planes to land on Naknek Lake, but I didn’t mind the view of Dumpling Mountain and the head of Brooks River.

lake and mountain scene

Dumpling Mountain and the outlet of Lake Brooks

After heading straight to the visitor center to get my bear orientation…

Ranger in log cabin talking to people

Yes, even former rangers are required to attend the bear safety talk upon arrival at Brooks Camp.

…I hurriedly pitched my tent in the campground….

tent in grass with tree in background

My tent in the far southwest corner of the campground, as far away from other people as I could get.

…and walked back to the lower river to binge watch bears.

wet tan-colored sand next to log

Fine pumice sand, evidence of the powerful winds from the previous day’s storm, was all over the beach.

In September, the wildlife-viewing platform near the mouth of Brooks River is my favorite place to be. Upstream, just where the river enters my line of sight from the platform, thousands of salmon work to complete their life cycle. As the fish weaken and die, the river’s current sweeps them downstream. Where the river’s current is not longer strong enough to carry them further, it drops the barely live and dead fish, making the river mouth and meanders just upstream the most productive salmon scavenging areas at Brooks.

When I arrive on the platform four subadult bears play and fish, while 409 Beadnose and cubs lounge nearby. After another large salmon run, the bears at Brooks River are well fed, and perhaps as a result the younger bears were especially playful.

brown bear standing with front paws on boulder

One light brown subadult bear out of this bunch very much resembles 273’s yearling in 2016. This bear appears to be a young subadult, but is large for a 2.5 year-old.

Around noon, after Beadnose and cubs settled into a nap below the platform, I decided to visit Brooks Falls, where bears had been fishing in higher than average numbers for this time of year. I had a hypothesis as to why, but I needed at least a few cursory observations to support it.

Over my short stay, the vast majority of fish I saw bears catch at the falls were silver (coho) salmon. This run begins in August and often continues through September. Larger on average than sockeye, a single, fresh silver salmon can provide several thousand calories for bears skilled enough to catch them. Like the beginning of the sockeye run in late June and July, the late run of silver salmon is most accessible to bears at Brooks Falls.

Bears standing at waterfall

Two adult male bears, 68 (left) and 879, fish the far pool of Brooks Falls.

But bears in the lower river make huge energy profits as well. In the early evening, after skipping a true lunch to eat an early dinner (to maximize bear watching time), I return to the lower river until sunset. 410 and 409 Beadnose both patrol the river slowly, snorkeling for any salmon that can swim away. In a half hour, 410 eats four fish. Over an hour, Beadnose leisurely consumes eight. These are relatively low catch rates for this section of river, yet even assuming the salmon carcasses provide less than half the energy they did in July (spawned out fish may contain 2000-2500 calories or less compared to the 4500 calories when the first arrived) 410 and 409 still ate at least 8,000 and 16,000 calories respectively. In past years, when 410 has remained within my line of sight longer at the lower river, I’ve counted her eating 41 fish in 3 hours 25 minutes. Even if she only ate part of each fish, when your profit is measured in calories needed to survive winter hibernation, this isn’t a bad day’s work.

As the sun begins to set behind the western toe of Dumpling Mountain, I relaxed to watch bears come and go from the river—128 Grazer, 409 Beadnose, 284, 410, 708, 610, four unidentified subadults, 879, 474, and many cubs. If the sun didn’t set so soon and I didn’t risk running a gauntlet of bears in the dark to get to the campground, I would’ve remained out for much longer. Responsible bear watching, however, includes not wandering around in the dark, so I retire to the campground eager for sunrise and another day on the river.

panorama of river and mountain near sunset

There is no average bear

In many ways, we can stereotype bears based on their age, sex, and reproductive status. While watching bears and even interacting with bears, certain stereotypes are useful. They help us begin to understand and explain a wide spectrum of behavior exhibited by a group of intelligent animals.

To stereotype a group of bears, adult males who rank at or near the top of the hierarchy are probably the least likely to act like a kid. They are the least likely to play or show overt curiosity towards new things. For most of bearcam’s history (2012-present) we’ve watched bears like 856, 747, and 814 dominate the falls through their size and assertiveness. These bears showed little interest in other bears except when establishing or reaffirming their dominance, stealing fish (especially 814 Lurch), appropriating preferred fishing spots, or when seeking a mate. Their behavior framed (biased?) our expectations of bears at the top of the hierarchy. They acted like stereotypical dominant males, and in their own ways, average bears.

But this logic can only take us so far, because there are no average bears.

This past July 32 Chunk displaced 856 as the most dominant bear at Brooks River. Chunk is approximately 12-13 years old and is perhaps the largest bear to use the river regularly this summer. Much of his behavior, especially early in Brooks River’s salmon run, is typical of a big dominant male. Not only did he displace other bears, he also wasn’t successfully challenged for food or fishing spots.

Notice how 856 quickly vacates the jacuzzi and doesn’t even attempt to challenge 32 Chunk.

Initially, 32 Chunk fit our expectations of a dominant male, but over the past two weeks or more bearcam has captured Chunk play fighting with another large, and older adult male, 755 Scare D Bear, as well as scavenging fish from him.

Just what is going on? Has Brooks Falls gone topsy-turvy in the wake of this summer’s hierarchy shift? Or this something more akin to the peculiarities of individual bear behavior during a summer when salmon are plentiful?

In July especially, Chunk fit the stereotype of a dominant adult male—challenging and displacing other bears, marking trees and cowboy walking in full view of other large males, and courting females. Since then, he’s behaved in ways that do not fit the dominant male stereotype—waiting patiently downstream of 755 for scraps of fish (a behavior more akin to scavenging than begging) and even initiating prolonged play fights with 755.

Play among adult male bears in their early teens is uncommon, but not unprecedented. I’ve previously wondered if bears outgrow play, and my personal observations suggest the frequency of play decreases as bears age. (I’m more surprised by 755 Scare D Bear’s willingness to play-fight, something I’ve never witnessed from him, than from 32’s).

Chunk’s play behavior separates him from bear 856 who was the most dominant bear seen through the entire history of bearcam until this summer. 856, like 24 BB before him, was hyper-dominant. As far as I know, this term has never been formally described in the scientific literature about bears. Tamara Olson, one of Katmai’s former bear biologists, introduced me to it. As I understand the term, hyper-dominance in bears is a willingness to continuously assert dominance over other competitors, giving them no slack, no chances to gain an edge. 856 became the river’s most dominant animal in 2011, when he was about the same age as Chunk is now. Once 856 became more dominant than 814 Lurch, for example, he repeatedly approached and displaced Lurch, perhaps in an effort to remind his large competitor, “Don’t challenge me or infringe on my space.”

Perhaps a lack of other large males who can challenge Chunk has allowed him to exhibit more playful and less hyper-dominant behavior. The relatively high abundance of salmon at Brooks River this summer also influences how bears interact with each other. To add another stereotype to the mix, bears are generally more playful and more tolerant of each other when they are well fed.

Because of his rank at the top of the hierarchy, we expect Chunk to behave like more like 856 than a youthful subadult. However, no biological edict commands Chunk to fit our expectations. His bimodal behavior is uncommon among adult male bears of his rank. Yet, Chunk can play-fight with other bears and still maintain an exceptionally high rank in the hierarchy.

The average bear is an amalgam of our observations and conclusions, created to help us better understand the lives of bears. No single bear will ever fit this role completely. Chunk can be both playful and dominant. He is no anomaly, because the average bear doesn’t exist.

Viral Bear Encounter with 435 Holly

Every once and a while a video from Brooks Camp goes viral. The latest involves a mother bear, her two spring cubs, and a person on the trail to the Brooks Camp Campground.

I’m a little late to opine on this video, but most of the responses and explanations (even Katmai’s, which explains what to do fairly well) seem to lack information about the bear’s behavior. Why did the mother bear and her cub approach the person?

The mother bear in the video is known as 435 Holly, an adult female who was first identified in 2001. This bear has led a storied life so far, successfully caring for her injured yearling in 2007 and adopting an abandoned yearling in 2014.

brown bear standing in grass near water

435 Holly in September 2015.

She’s also one of the most human habituated bears known at Brooks River. (Habituation, in this context, is a waning response to a neutral stimulus.) As a result, this bear is not as likely to react as defensively towards people compared to many other bears. Holly frequently uses the developed area from the river mouth to the campground, often traversing the area near Brooks Lodge, the NPS visitor center, and employee housing. She’s even treed herself near the bathrooms at Brooks Lodge and approached large groups of people.

The ranger handled this particular situation well, gathering the group of people together to let the bears pass. Corralling people isn’t easy though. Despite the best efforts of rangers, some people are always willing to push the limit with bears.

Bear near group of people. Arrow pointing towards person who is separate from group.

It’s not a wise move to leave the safety of your group when a mother and cubs is only feet away.

On more than one occasion, I watched Holly walk down “Park Avenue” in front of my cabin, sometimes to avoid other bears and sometimes just because that was the easiest way to get where she was going.

Her behavior demonstrates a relative tolerance for people. She’s not shy about using the same trails as us, which brings me back to the viral video. 435 Holly has encountered many, many people at Brooks River and humans have largely been a neutral stimulus in her life. These factors enable situations like these to happen on a regular basis at Brooks River.

In the viral video, neither Holly nor her cubs show signs of stress or defensiveness. She doesn’t lower her head, her ears remain upright, and she makes no vocalizations. Holly’s cubs reflect their mother’s relaxed state, casually walking with and occasionally in front of mom. They know a human is near and as he backs away, she continues in the same direction. Holly, in this situation, wanted to use the trail. She did not threaten the person or act in a defensive manner.

Of course, there was real risk involved during the encounter and my thoughts should not be misconstrued to downplay the risk. Any encounter with a bear, especially a mother and cubs, needs to be taken seriously, for our own safety and also for the welfare of the animals. If this was different mother bear, with different tolerances and reaction distances around people, then the situation could be different.

This doesn’t mean the person on the trail would be mauled, however. At Brooks River, females with cubs who are not habituated to people are likely to be displaced from the river during periods of high human use, and we shouldn’t approach bears just because they’ve shown tolerance towards us in the past. In areas where bears need more individual space it is even more important to prevent close encounters.

This encounter with 435 Holly and her cubs was the result of a very human habituated bear needing to use the trail at the same time as a person. Her motivation, in this particular case, wasn’t a need to protect her cubs, assert dominance over a person, or even curious approach. It was simply to walk on the trail.

For information about what to do in encounters like this at Brooks Camp, please see Katmai National Park’s video response. That response however, is not usually applicable to bear encounters in other areas of North America.

End of an Era

The bear hierarchy is fluid. Bears jostle constantly within it, gaining and losing rank as they grow into adults and age into older bears. In 2017 at Brooks River, one bear has asserted his dominance over all others in ways he’s never done before. There appears to be a new dominant male on the river and he’s known as 32 Chunk.

bear standing in grass

32 Chunk in early June 2017. Photo courtesy of Katmai National Park.

In 2011, I began recording interactions between bears at Brooks Falls, noting who displaced who, who avoided who, and which bears were courting, stealing fish, and playing together. Out of hundreds of interactions I witnessed, one bear was consistently and clearly dominant over all others, 856.

bear standing in water

856 stands in Brooks River on June 30, 2016.

From 2011 to 2016, 856 wasn’t displaced once. I only noted him yielding on very rare occasions, like when he faced a particularly defensive mother bear. No other bears even seemed to challenge him. 856 ascended to the top of the hierarchy rather quickly in 2011, outcompeting other large males like 814 Lurch and 747, and for many years remained the river’s most dominant bear.

two bears facing each other in water

856 (right) displaces 747, another large adult male bear, from the jacuzzi in 2013.

Life at the top of the hierarchy is difficult, however. Other bears are subordinate, but not subservient, to more dominant animals. If injury, illness, or age weakens a dominant bear then others will not hesitate to usurp their position, gaining greater access to food and potential mates. Other bears, often younger and stronger, are more than willing to take your spot if given the opportunity.

In the video above, 856 is the bear in the jacuzzi (the plunge pool below Brooks Falls) while 402, an adult female, stands on the lip. Notice how 856 turns to face the bear approaching from the far side of the river. This is 32 Chunk.

Screen shot from video. Three bears near a waterfall. Text reads "402," "856," and "32 Chunk."

856 backs out of the jacuzzi to avoid 32 Chunk. He then goes to the lip where 402 stands, but 32 Chunk follows. Above the falls, 856 makes no attempt to challenge Chunk. 856 stands and watches as 32 turns away from his competitor, like dominant bears are apt to do, and walks out of the frame.

Generally, when two bears of approximately the same size and disposition meet for the first time, both bears posture openly as they evaluate each other’s size and the potential to do physical harm. 856 yielded quickly and readily to 32, so they have encountered each other before the video above was recorded. During a previous encounter 32 Chunk may have asserting his dominance even more clearly, hence 856’s willingness to yield. 856 simply saw 32 approach and instantaneously realized he could not challenge the larger 32, so he backed away to avoid picking a fight he probably wouldn’t win. (Many, if not most, interactions between bears are like this. They are defined by avoidance.)

bear standing in water and facing the right side of the photo

32 Chunk in 2014, while he ranked in the middle of the bear hierarchy for adult males.

Nature abhors a vacuum. No niche is left unfilled within the bear hierarchy. 856, perhaps weakened by injury or age, appears to no longer be the most dominant bear at Brooks River. His younger competitor sensed weakness and exploited it. This isn’t a contest of longevity though. During his time as the most dominant bear, 856 had free reign over the best fishing spots and went unchallenged for access to females in estrus. For years, he grew large and strong, probably siring more than one litter of bear cubs along the way. Now 32 Chunk (and possibly other bears like 747) hold those advantages.

856 remains a large bear and his size will continue to allow him great access to fishing spots at Brooks River. Bears grow up quickly, gaining the strength and skills necessary to survive a harsh, competitive world. Eventually though, the competition catches up.

Hierarchy Shift

Brown bears live in a hierarchy, where dominance allows greater access to food and the most productive fishing areas. One recent interaction between bears 32 Chunk and 480 Otis represents a shift in this social order. This is a story of maturation for two bears going in opposite hierarchical directions.

The hierarchy at Brooks River allows bears to quickly assess their competitors, avoiding most physical fights and saving valuable energy. Within the hierarchy large, mature males rank highest followed by other adult males, females with cubs, single females, and finally subadult bears. While this pattern holds as a general rule, bears shift their position in the hierarchy depending on their size, strength, and overall health.

As an adult male in his early teens, 32 Chunk is well positioned to rank near the top of the hierarchy. Chunk was first identified in 2007 as a chunky subadult bear. We don’t know his exact age, but bear monitoring staff noted he appeared to be a young subadult, perhaps 3.5 or 4.5 years old at the time. Since then, he’s grown considerably and is among the largest bears at Brooks River.

small bear standing in grass

32 Chunk as a young subadult in 2007. Ten years later, he has grown to become one of the largest bears at Brooks River. (Photo courtesy of Jeanne Roy.)

In contrast, 480 Otis was a mature adult in his early teens in 2007. He was a big, walrus-shaped bear who, like today, was skilled at fishing in the jacuzzi and far pool. He was not often displaced from his preferred fishing spots.

bear in water

480 Otis in 2007. (NPS Photo)

In 2007 and 2008, a young subadult bear like Chunk wouldn’t even consider challenging a larger adult like Otis. Since then both bears have matured, but their life histories since then lead in different directions within the hierarchy. Recently, 32 Chunk demonstrated his dominance over the older 480 Otis.

When the video begins, 480 Otis is standing upstream of the falls in the middle of the river. 32 Chunk is the darker colored bear in the jacuzzi below the falls.

screen shot from video of waterfall. one bear sits below the falls and another is in the river above the falls

After Chunk notices Otis above the falls, he leaves the jacuzzi and begins to approach Otis.

screen shot from video of waterfall

480 Otis starts to move away, possibly to avoid 32 Chunk’s approach. This is one sign Otis could be subordinate to 32. The rest of the interaction leaves no doubt who is dominant, however.

screen shot from video. Dark bear approaching another bear above the waterfall.

Chunk moves through the river faster than Otis. When Chunk nears the older bear, Otis turns to face the younger competitor. They stand mostly still, yawning and assessing each other’s size.

screen shot from video. two bears standing in river above the falls.

32 Chunk then swats at 480 Otis.

screen shot from video. bear swats at another, splashing water

In the video, the bears’ ear positions aren’t easy to see, but 480’s ears seem to be held back against his head, indicating he’s somewhat defensive. Chunk’s ears, in contrast, are mostly upright and oriented forward, a sign of assertiveness and dominance in this context.

screen shot from video. two bears standing near each other in water

The interaction ends when 32 Chunk walks away with 480 Otis watching.

screen shot from video. Dark bear walking away from lighter bear

Several behavioral cues demonstrate 32 Chunk’s dominance and 480 Otis’ subordinate status in this interaction.

  • 32 directly approached 480.
  • 480 attempted to avoid 32.
  • 32 lunged at 480 and 480 did not attempt to engage.
  • 32’s ears were upright and forward, while 480’s ears were held slightly back against his head.
  • 32 ended the encounter, turning his back on 480 and walking away. (Dominant bears decide when an interaction ends unless they have good reason to usurp a resource such as food, a fishing spot, or access to a potential mate.)

Chunk is now entering the prime of his life where he’ll attain his greatest size and rank, and while Otis remains a large bear he’s no longer able to compete with the largest male bears for fishing spots. It seems that Chunk recognizes his size and strength and Otis recognizes the great risks of challenging a younger, larger bear. For the rest of the summer, 32 may displace 480 from fishing spots at Brooks Falls.

Chunk appears to be moving up the hierarchy while Otis continues to slide down it. With these bears, there are two tales of maturation.

When Mother Bears Collide (Again)

Last summer, 128 Grazer and 409 Beadnose found themselves face to face in defense of their cubs . Recently on bearcam, they had another dustup. This one was unique and included elements I had never observed before.

When we ask, “Why did that bear behave like that?” we should ask two additional questions.

  • Was the bear motivated by food or potential access to food?
  • Was the bear motivated by sex or reproductive success?

Biology can be distilled simplistically into two categories: food and sex. Adequate nutrition is necessary for survival of the individual, and since bears hibernate throughout much of the year they are particularly motivated by food. Reproduction also drives bears to behave in particular ways. We should also consider how each bear’s disposition influences their behavior.

128 Grazer
As a young adult bear, 128 Grazer became very skilled at fishing the lip of the falls. She’d compete for access to that spot with several other adult males and females. As a single bear (i.e. no cubs), she was fairly tolerant of other bears in close proximity. After 128 became a mother in 2016 though, her behavior became increasingly defensive. She didn’t shy away from confronting larger adult males in order to protect her cubs .

Still caring for three yearlings in 2017, she seems to be just as protective and wary as last year.

409 Beadnose
In contrast to Grazer, 409 Beadnose is an experienced mother who has weaned three litters (her current batch of yearlings is her fourth known litter). Beadnose can be defensive too, but tends to avoid confrontation more often than 128. While Grazer visited the falls with her spring cubs last summer, 409 did not. This is a clear behavioral change for Beadnose, because she visits the falls frequently when she’s not caring for cubs.

two bears standing in shallow water

128 Grazer (left) and 409 Beadnose are familiar with each other and often use the same areas to fish.

Now both of these mothers are raising yearlings, both have returned to Brooks Falls, and both tend to fish the same places (the lip or the far pool). Most importantly, both are competing for the same resources in order to successfully raise their cubs—leading to situations like this.

Can this apparent snafu be explained by a motivation for food or reproductive success? When the video begins, 409 Beadnose is ascending the hill. 128 Grazer is the blonder bear standing under the spruce tree. Grazer refuses to yield to Beadnose’s approach. The bears jaw and growl at each other, while 128’s yearlings remain in the spruce tree above their mom.

screen shot of bears beneath spruce tree

Beadnose seems compelled to get up the hill and skirts Grazer. There are other routes available, but she sticks with this one.

screen shot of brown bear on hill near spruce tree

Grazer’s cubs eventually come down from the tree while Beadnose lingers in the forest nearby. Something keeps Beadnose from moving farther away, but at this point we can’t see her.

bears standing on his near river

With 409 still on the hill, Grazer and cubs move down to the river. Shortly afterward her yearlings react to something in the same tree they had just climbed down from. Grazer begins to jaw pop, a loud and distinctive warning noise. We can see movement in the spruce tree above.

four bears standing in river near a steep embankment

It’s one of Beadnose’s cubs.

four bears standing in river. Yellow circle surrounds bear in tree. Text reads, "409 yearling"

Grazer and her yearlings scramble up the hill just 409’s yearling tries to climb down. Now we understand why Beadnose didn’t give Grazer more space previously and why Beadnose remained in the forest near spruce tree—one of her cubs was in the same tree as Grazer’s cubs! This is something I never witnessed before, cubs from two litters in the same tree at the same time.

409 is mostly out of sight as 128 and cubs run up the hill. 409’s yearling though, is unable to get out of the tree.

Two bears climbing a hill. Yellow circle highlights a bear in a spruce tree. Text reads, "409 Yearling"

A short stand-off ensues. 409’s yearling remains in the tree, 409 stands not far up the hill, and 128 Grazer and yearlings remain close by.

Screen shot of bears on hill in vegetation. Yellow circles highlight location of bears. Text reads, from top to bottom, "409 yearling" "409 Beadnose" "128 Grazer"

When 409’s cub tries to climb down again, Grazer reacts and charges to the base of the tree.

screen shot of bear standing on hill near river

Grazer then climbs the tree, forcing Beadnose’s yearling back up. About ninety seconds later, 128 has moved farther away, which allows 409’s cub to climb out of the tree and rejoin its mother.

This interaction between Grazer and Beadnose was unique because cubs from two different litters were in the same tree at the same time, greatly complicating a situation where the families could’ve avoided each other. The interaction was ordinary however, because both Beadnose’s and Grazer’s behavior seemed to be motivated by an urge to protect their cubs. Grazer’s defensiveness is easily triggered and she must’ve viewed the 409 yearling as a threat, which in my opinion led her to chase it back up the tree. Beadnose may have realized Grazer was willing to physically fight in this situation. This could’ve deterred Beadnose from standing next to the tree under her cub. At the beginning of the video, Beadnose also couldn’t get her cub out of the tree with Grazer’s cubs still in it. Stuck in a Catch-22, Beadnose seemed to choose a more cautious tactic: move slightly away and wait.

Motivation for food or reproductive success explains quite a lot in biology, but not all bear behavior can be explained so simplistically (why would a bear play with her foot? ). The prolonged interaction between these families however, does fit one of the biological motivators. This interaction probably wasn’t hierarchical; that is, it wasn’t about asserting dominance for access to food and mates. It was about protecting offspring. In other words, it was about reproduction.