Brooks Falls

Chunk Didn’t Displace 856

/ Mike Fitz / 18 Comments

A few days ago, bearcam viewers alerted me to an interesting interaction at Brooks Falls where 32 Chunk appeared to displace 856.

I’ve taken some time to review bearcam footage of the subordinate bear in the video above, and I don’t think he is 856. The bear looks like an adult male, based on his size and the presence of scars around his face. I don’t recognize him, but I am willing to say it is not 856. Here’s why…

856 is a large adult male with blond ears and a long neck. This year he returned with a noticeable limp and sports a shed patch on his rump.

856 will fish at several different places in the falls—the jacuzzi, in the far pool, and near the rocks in between. When he sits at the rocks, he does so in a fairly distinctive manner.

When 856 fishes the jacuzzi, he’ll often leave that spot to eat near the island, almost sitting and facing away from the cam.

In contrast to these behaviors, the bear displaced by 32 Chunk doesn’t appear to be limping (and I’ll admit that bears can heal quickly, so the limp may not be very pronounced now). Both 856 and the unidentified bear may have similar wounds or scars on their face, the ears of the bear displaced by 32 Chunk are darker. The contrast between the unidentified male bear’s front quarters and hind quarters is also more apparent than 856. His muzzle appears blockier than 856, and 856 is very unlikely to play with 89 Backpack.

bear standing in water near waterfall

This is a screen shot of the unidentified adult male who displaced by 32 Chunk.

bear standing on grass near water

856 walking on the island near Brooks Falls in July 2015.

So was this a changing of the guard at Brooks Falls? Probably not. In my opinion, 32 Chunk displaced a full grown adult male, but the subordinate bear was not 856. However, in the absence of other large males like 856 and 747, 32 Chunk may be the most dominant bear on the river. Chunk clearly asserted his dominance over the unidentified male.

Almost every year, a new and fully mature adult bear shows up at Brooks River. Bears are creatures of habit, but they also remain flexible, changing their behaviors when necessary. The unidentified male may have never visited Brooks Falls before and never encountered 32 Chunk. His life up until now is a mystery, but these events are one reason why the story of Brooks River’s bears is so fascinating. This is a constantly evolving story. It will never become static.

View more photos of 856 from 2015 and 2016.
(Thanks to bearcam fan stmango for compiling many videos for me to review.)

Hierarchy Shift

/ Mike Fitz / 9 Comments

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)

/ Mike Fitz / 7 Comments

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.

Bear Courtship

/ Mike Fitz / 3 Comments

Bearcam is back! While brown bears fishing at Brooks Falls are the cam’s main attraction, bears also engage in another important event—courtship. Bears make new cubs at this time of year.

Courtship is a conspicuous part of bear life in spring and early summer. Sometimes a male bear encounters a female bear at the right time and they copulate immediately, but more often bear courtship is a prolonged affair. From an ursine perspective, courtship is a process in which a male follows a female in estrus, habituating her to his presence until she is ready to mate.

large bear (right) follows smaller bear through grass

A large adult male, 856 (right), follows 708 Amelia while she was in estrus in 2013.

Courting pairs are easy to recognize by the male’s conspicuous and persistent behavior. A male bear recognizes an estrous female by her scent. He then walks behind her, shadowing her movements like he has a laser sight affixed to her rump (hormonally, the simile may not be far from the truth). However, bear courtship contains neither romance nor effort from the male to attract the female. He’s simply biding his time.

Copulation takes place only when the female is ready, which may not be for days. (The longest courtship I ever noted at Brooks River was 10 days.) It’s certainly not uncommon to see a male following a female for hours and hours.

Over those hours and days, the male follows her, guarding his access for the opportunity to mate. If another male of equal or greater dominance catches the female’s scent, then the two males may engage in a violent fight. Male testosterone levels peak, not coincidentally, in June as well. In late spring and early summer, fresh wounds on dominant adult males may be battle scars from a fight for access to a female bear. Bigger can be better in the bear world.

large bear with wound on cheek sitting in water

In June 2015, 814 Lurch returned to Brooks Falls missing an ear and with a large wound in his right cheek. These wounds could have been received during a fight with another male over access to a female.]

The victor continues his slow pursuit until the female decides the time is right. Outside of the mating season, male bears pose real threats to smaller females (sometimes, albeit very rarely, killing them) so the close, persistent proximity of a large male must be alarming at first. Eventually, hormones and habituation to the male overcome her initial trepidation.

Even then, the female may not be ready.

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Copulation lasts upwards of twenty minutes. Brown bear females are promiscuous and may mate with more than one male. Her estrus cycle isn’t a single event. She can have several over the mating season, which generally runs May through July. Female black bears may be induced ovulators, so brown bears could be too, and while no evidence of multiple paternities has yet been confirmed at Brooks River, a single litter of cubs could have multiple fathers.

mating bears

218 Ugly mates with 402 at Brooks Falls in 2010.

If mating is successful, the fertilized egg divides only a few times before entering a state of arrested development in the mother’s uterus. Only after she enters the den in the fall will the blastocyst begin to grow again. Through this delayed implantation, female bears can focus the rest of their summer efforts gaining enough fat reserves to survive hibernation. This allows cubs to be born in mid-winter when they are most protected in their mother’s den.

Over the next few weeks on bearcam, watch for male bears to doggedly follow single females. This is the most conspicuous sign of bear courtship, a season is marked by competition, conflict, persistence, and the promise of another generation of bears at Brooks River.

Brown Bear Fatness Index

/ Mike Fitz / 6 Comments

Brown bears get fat, often really fat. They also lose a lot of weight and sometimes become really skinny. They are often fat and skinny in the same year. When you watch brown bears, either in person or via bearcam, you can sometimes make a fairly accurate determination of a bear’s body fat and relative health by looking at its shape.

Fatness can be used as an indicator of health in brown bears. Brown bears need to eat a year’s worth of food in six months or less to survive, and body fat is the key their survival. They can lose 30% or more of their body weight during hibernation and can continue to lose weight throughout the spring when few high calorie foods are available. In the Brooks River area, only after green plants begin to grow and salmon have arrived do most bears begin to regain lost weight and start to accumulate body fat.

While fat is important to bears, a thin bear isn’t necessarily an unhealthy bear. Young subadult bears and yearling cubs, for example, often appear thin in spring and early summer before many high calorie food sources are available. These bears usually regain lost body mass in summer and early fall.

Polar Bear International developed a handy scorecard to measure the relative fatness of polar bears. I’ve adapted it for brown bears. My brown bear fat index uses the same categories as the polar bear index, which ranges from skinny/emaciated to very fat/obese. I also included additional information for each category such as the age/sex class most likely to be in a category and the time of year bears are most likely to be in a category.

Please note, my brown bear index is subjective and based on my observations at Brooks River, Katmai National Park, Alaska. The polar bear fatness index is also subjective, but less so than mine because researchers who handle immobilized bears can palpate the animal to estimate its body fat content. (Katmai’s Changing Tides project also tracks body fat content in female brown bears, but uses bioelectric impedence analysis.)

Brown Bear Fatness Index

Emaciated: bear appears skinny with ribs, vertebrae, and hip bones usually clearly visible unless covered by fur.

  • Time of year most likely to happen: late winter through early summer, but can happen in all seasons.
  • Age/sex Class: Older bears, especially older mothers with newborn cubs and injured bears
emaciated 16 Cinnamon.jpg

16 Cinnamon shows an emaciated figure in July 2010. Notice his prominent hip bones and shoulder blades. If he had less fur, his ribs would also be noticeable.

emaciated 16 Cinnamon_2.jpg

In this photo, also from July 2010, Cinnamon’s vertebrae seem visible through his fur. Despite his lack of body fat in July, he survived winter and returned to Brooks in 2011. At the time, he was estimated to be at least in his late 20s, but could’ve been older.

Thin: vertebrae and hip bones partly visible; narrow body

  • Time of year most likely to happen: late winter through early summer, but can happen in all seasons.
  • Age/sex class: subadults, yearling cubs, 2.5 year-old cubs, older bears, and mothers with newborn cubs
thin 234 Evander fishing near the far pool 2.jpg

234 Evander in July 2010 displays a thin body with noticeable hip bones. Evander was an older bear (probably older than 20 years) in 2010.

thin 503.JPG

In this photo from early July 2016, 503 Cubadult appears thin with slightly visible hip bones. His narrow body shape is not uncommon for young subadult bears (he was 3.5 years old in July 2016), and does not necessarily indicate poor health. Rather it reflects the time of year and his low rank in the bear hierarchy.

Average: hip bones and ribs not visible; the bear’s body, neck, and head are evenly proportioned

  • Time of year most likely to happen: all year, but most often summer
  • Age/sex class: all ages
average 505.JPG

This adult female, 505, is well proportioned and a good representative of average fatness for an early to mid summer bear. Photo taken on July 8, 2016.

Fat: fat over rump, stomach hangs low; bear’s neck is semi-fat but doesn’t distort the size of the head

  • Time of year most likely to happen: late summer and fall
  • Age/sex class: adult males in prime of life in mid summer, all bears late summer and fall
Fat 89 Backpack_03_09132015.JPG

Katmai’s brown bears most often reach the fat class in late summer and fall when salmon are readily accessible and have been so for two months or more. In this photo from September 2015, 89 Backpack displays the typical body shape of a fat bear. Most bears attain this body shape before they hibernate.

fat 747.JPG

Sometimes large adult males, like 747, can reach the fat category by the end of July. Some bears aren’t this fat when the go into the den, yet 747 reached this size months before hibernation. This photo was taken in late July 2015.

Obese: stomach hangs very low; bear’s neck is very fat and makes head appear smaller in proportion to its body

  • Time of year most likely to happen: very late summer and fall
  • Age/sex class: adult males in prime of life and adult females without cubs
Obese 747.jpg

This NPS photo of 747 epitomizes an obese bear. (He should’ve won #FatBearWeek. Election was rigged!) Seriously, this is an extremely obese bear. I don’t think I’ve ever seen a bear this fat before. His belly hangs nearly to the ground (the water is not very deep where he stands in the photo). 747 is a very dominant adult male at Brooks Falls. As such, he has access to his choice of fishing spots. His well-endowed figure is proof of his dominance, health, and fishing skills.

Obese 409 Beadnose_45_09232015.JPG

409 Beadnose shows the ample proportions of an obese female in September 2015. Females with cubs do not usually attain this level of fatness because of the energetic costs associated with raising cubs. Beadnose did not have cubs in 2015.

Strut Your Stuff

/ Mike Fitz / 12 Comments

In my last post, I broke down an interaction between two mother bears, one of whom was particularly defensive. Bears though don’t always charge and threaten violence to make their point. As this video illustrates, bears communicate through body language to establish dominance and avoid conflict. (Warning: Long Video.)

In the video, 747 is the heftier, darker bear. 68 is the tall, lanky bear. Both are mature adult males, likely in the prime of their lives. As I see it, bear 747 comes out of this on top as he asserts his dominance over the newcomer, 68. This took some time, however. 68 didn’t exactly yield like most would upon the approach of 747.

As the video starts, 747 (left) immediately approaches the newcomer on the island. 68 subtly skirts 747, but continues his approach toward the falls. You can see that 747 is much bulkier than the newcomer, but the new bear is just as tall, if not taller.

Screen Shot 2016-10-14 at 10.49.25 AM.png

747 (left) approaches 68 on the island downstream of Brooks Falls.

When 747 turns his back on the new bear, 68 takes the opportunity to mark some grass (0:50). 68 is not acting submissive or yielding.

Screen Shot 2016-10-14 at 10.50.10 AM.png

After a brief do-si-do, 68 (left) marks grass while 747 does the same.

The new bear approaches 747. 747 stands and watches. At this point, the outcome is very much undecided (1:12).

Screen Shot 2016-10-14 at 10.51.34 AM.png

68 (left) approaches 747.

After a little more posturing, 747 turns to mark the willow on the island. This is a bold display of dominance in front of 68. The newcomer though continues to cowboy walk away from 747, still not submissive but very focused on 747’s movements (2:00).

Screen Shot 2016-10-14 at 10.52.50 AM.png

747 marks a willow tree while 68 postures nearby.

747 follows the exact same route on the island as 68, probably following the newcomer’s scent and leaving his own on the way (2:20). 68 postures more in the grass. 747 again marks the tree. This time for almost 30 seconds (3:18).

Screen Shot 2016-10-14 at 10.53.28 AM.png

747 says, “This is my turf.”

747 then goes to the grass where 68 just was and rubs it on his body. He seems to want to leave a scent trail everywhere his competitor has (4:05).

Screen Shot 2016-10-14 at 10.53.59 AM.png

747 (center) marks the grass where 68 had just walked.

68 walks downriver. 747 follows. In the riffles, 747 catches up to him. Instead of fighting, the bears posture more. Here’s where 747 seems to assert his dominance more clearly. 68, instead of posturing further, stands in the riffles and watches 747 approach then walk away (5:00).

Screen Shot 2016-10-14 at 10.54.21 AM.png

747 pursues 68 downstream.

The video cuts to a moment a few minutes later when 68 makes his way back to the island. This draws 747’s attention and he approaches 68 again. 747’s ears remain upright and forward, a sign of dominance in this context. The new bear’s ears are oriented back against his head, a sign of defensiveness (6:40).

Screen Shot 2016-10-14 at 10.55.34 AM.png

747 (left) directly approaches 68 one last time. Note the bears’ ears. 747’s are pitched forward like he is not intimidated by 68.

747 circles 68. 747 walks away and the newcomer stands and watches, indicating that 747 successfully asserted his dominance in the interaction. 747 then goes back to the island and marks the vegetation again (7:05). 68 continues to stand and watch. Winner: 747.

747_06272016.JPG

747 is one of the largest and most dominant bears at Brooks River.

During encounters between adult male bears, the “winner” is the bear who ends the interaction, usually by walking away. This is exactly what 747 did. (Exceptions are when bears compete over a resource they want like food, a fishing spot, or access to a female. In those cases, the dominant bear stays where he wants, displacing the subordinate bear who usually moves away.)

Any time a new bear arrives at Brooks Falls, my interest piques. Newcomers are often wildcards. They may or may not know how to fish the falls and must weave their way into the river’s hierarchy. 68 was never identified at Brooks Falls in July. I didn’t recognize him when he arrived. He seemed to show some familiarity with the falls area and wasn’t particularly wary of other bears. When 747 saw the newcomer I thought, “This could get interesting.” It did, just in a non-violent way.

68 and 747 communicated their intentions clearly through posturing and marking vegetation. Throughout the entire video, these bears get very close to each other, but never make physical contact. Both want to hold high places in the hierarchy, because dominance confers many advantages. Through a continued, confident approach and more exaggerated posturing, 747 asserts his dominance over the newcomer. This is a classic, albeit lengthy, example of bears using body language to communicate their intentions, avoid physical conflict, and establish dominance.

For more information on Katmai’s bears, download the latest edition of Bears of Brooks River: A Guide to Their Identification, Lives, Identification, and Habits.

When Mother Bears Collide

/ Mike Fitz / 39 Comments

What happens when two mother bears, both with spring cubs, meet?

Defensiveness is a trait of all mother bears. In the video, 128 Grazer is the blonde bear with three spring cubs, and her defensiveness is immediately evident. She jaw pops and salivates as 409 approaches.

Mother bear standing near cubs at base of a tree.

128 Grazer stands next to her cubs. Her excessive salivation is a sign of stress.

Meanwhile, 409 shows no signs of aggression. She probably just wants to get to the river and fish. Her two cubs are behind her.

Bear standing in grass.

409 Beadnose stands the in grass right before Grazer charges.

128 charges 409. If you listen carefully, you can hear one or both bears utter a low bellow.

Two bears with open mouths in grass.

Beadnose (left) and Grazer (right) face off as Grazer stops her charge just short of contact.

409 stands her ground (unlike an adult male who encountered a charging 128) likely because she’s protecting her cubs too. 409’s cubs climb separate birch trees. Now both sets of cubs are up trees. The mother bears can’t go far in this situation.

Bears in grass with cubs in trees.

Beadnose and Grazer face one another while their cubs remain in nearby trees.

The situation de-escalates quickly, which is not uncommon in encounters between bears. 128 then moves back to the tree holding her cubs. Beadnose slowly approaches the river then turns toward her cubs, almost like nothing happened. Both mothers keep watchful eyes on the other.

bears standing at the edge of a waterfall

409 Beadnose (left) stands near 128 Grazer on the lip of Brooks Falls in 2015.

Last year, these bears were extremely tolerant of each other. Cubs change the dynamic though. As a new mother, 128 behaved particularly defensive around bears and people in late June and early July. Beadnose’s relatively calm disposition may reflect her greater experience raising cubs (this is her fourth litter) and her high tolerance for certain bears like Grazer. Perhaps Grazer’s aggression is a product of her inexperience. This is her first known litter.

The bears’ experience and disposition factored into the interaction. Each encounter between bears (and bears and people, for that matter) is unique. Defensiveness is one possible reaction when mother bears collide.