Monday, March 16, 2009

2008 KATMAI BEAR TRIP REPORT: PART 5 (GEOGRAPHIC HARBOUR - INDIVIDUAL BEARS)

Al (a.k.a. Scarface) - the alpha boar in Geographic during our stay in 2008.

One of the big stars of Geographic was a big, heavily scarred male that we called “Al” (as in Al Pacino - Scarface). He appeared to be the dominant bear, as all other bruins in the area gave him wide berth. While we never saw any bears fighting at Geographic, the evidence of some serious combat was obvious.

A boar with a serious flesh wound. Injuries like this typically heal very quickly.

On one of our last days in Katmai, we observed a large boar with a flap of flesh peeled back from a large, open wound on its hind quarters. Every adult boar had war wounds. In most cases, these were gashed on the forelegs or wounds around the neck area. One bear had a gash on its head that almost reached the eye (at first we thought the eye had been damaged). While everything seemed fairly copasetic during our stay, the area was no doubt an arena from some terrific bruin battles.

A large boar bearing wounds on the forelegs and around the neck - war wounds from intense bruin battling!

Grizzly Aggression

Stonorov and Stokes (1972) found that there were four situations in which aggression most often occurs in brown bear aggregations. They were: 1. when one bear moves too close to another bear (invades personal space) 2. when one bear loses a challenge but then redirects its aggression toward a nearby bear (displacement aggression) 3. when two bears compete for a preferred fishing site 4. when two strange bears meet.

Stonorov and Stokes describes what happen during an intense, aggressive encounter between two bears that are similar in social ranking. The first thing that occurs is the bears confront one another – the two brown bears face each other with the front legs stiffened, the heads are lowered slightly and the movements occur in slow motion, the ears are laid back, both have their mouths wide open (this exposes the canines) and there is excess saliva production.

One of two things may happen at this point – one of the bears may back down or one or both bears may charge one another. When charging occurs one or both bears run at each other, the head is lowered and the ears are back and the mouth is open slightly. If neither bear breaks off the charge and retreats at this point, the big bears will come to blows. The bruins may swipe at each other with their fore paws, bite each other (usually on the neck) or lock jaws.

When one bear has had enough, it will drop its head even lower than its opponent and begin to slowly back away. At some point, the subordinate may walk or run away. During much of the encounter, there will be lots of vocalizations.

References:

Stonorov D. and A. W. Stokes. 1972. Social behavior of the Alaska brown bear. Int. Assoc Bear Res. & Mang. 23: 232-242.

© Scott W. Michael

Friday, March 6, 2009

"PSYCHEDELIC" FISH PICTURE: New Species Bounces on Reef

Photograph copyright David Hall/seaphotos.com

February 25, 2009—A recently discovered "psychedelic" fish (shown in a January 2008 picture) is bouncing into the books as a new species, a new study says.

With a swirl of beige and peach stripes stretching from its blue eyes to its tail, the newly named Histiophryne psychedelica was initially discovered by scuba diving instructors working for a tour operator a year ago in shallow waters off Indonesia.

The operator contacted Ted Pietsch, lead author of a paper published in this month's edition of the journal Copeia, who submitted DNA work identifying the psychedelic fish as a new species.

Like other frogfish—a subset of anglerfish—H. psychedelica has leglike fins on both sides of its body.

But it has several traits not previously known among frogfish, wrote Pietsch, of the University of Washington.

Each time the fish strike the seabed, for instance, they push off with their fins and expel water from tiny gill openings to jet themselves forward. That and an off-centered tail cause them to bounce around in a bizarre, chaotic manner.

Mark Erdman, a senior adviser to the Conservation International's marine program, said, "I think people thought frogfishes were relatively well known, and to get a new one like this is really quite spectacular. ... It's a stunning animal."

The fish, which has a gelatinous, fist-size body covered with thick folds of skin that protect it from sharp-edged corals, also has a flat face with eyes directed forward, like humans, and a huge, yawning mouth.

—Robin McDowell in Jakarta, Indonesia (Associated Press)

Click here to see some amazing video clips of this wonderful frogfish.

French surfer killed in New Caledonia shark attack

From correspondents in Noumea/ Agence France-Presse
March 06, 2009 07:33pm

A YOUNG French man has died after he was attacked by sharks while surfing in New Caledonia, police say.

The 19-year-old student's arm was ripped off and his leg bitten when he was attacked "apparently by several sharks" while trying to get back onto a boat with his friend on Friday, police said.

The man's friend managed to get him to shore, but he was dead by the time emergency workers reached him.

The incident took place in an area popular with surfers and was the first fatal shark attack in the French Pacific territory since September 2007, when a young nurse was killed.

The victim was from northwest France but was studying in the New Caledonia capital, Noumea.

BROWN BEARS: HANDLING AND INGESTING FISH PREY

A large boar gives its salmon prey a hug before "processing" it for ingestion.

Grizzlies use a number of different handling techniques when feeding on salmon. In most cases, the savvy “fisherbear” will grasp its prize in its jaws and carry it from the waterway to the shore, a gravel bar or surrounding grassy meadow/woodland (subordinate grizzlies, in the presence of conspecifics, are often more likely to move farther from the capture site than larger, more dominant bears). They then place their catch on the ground and stand on it with the fore paws. How the prey fish is processed may vary from one individual to the next or from one location to another. In many cases the first thing a bear will do is bite down on the posterior region of the fish and remove the tail section. Another body tissue targeted early in the handling process is the skin. To skin its quarry, the bear will grasp the skin with the incisors and pull upward, peeling the integument from the salmon’s body.

If food is in short supply (e.g., it is early in the salmon run or if fish numbers are down) the bear will consume the entire fish. If food is abundant, the bruin may select the choicest parts of the fish and leave much of its behind for scavenging birds, other mammals or even other bears (e.g., subordinate individuals or those that are poor at fishing). As mentioned in other posts, the skin is preferred as are the brains, but rather than ingesting the entire head, the bear often bites through the top of the cranium and laps out the brain or plucks them out with its incisors (see video footage below).

Not all bears take the time to leave the stream to eat their prize. It is not uncommon to see a bear, standing in knee deep water, clamping the fish against the front foreleg with the opposite paw (some bears employ this technique when eating fish on shore). The bear then rips the fish apart, one bite at a time. If the water where a fish is captured is shallow enough, some bears will pin the fish to the stream bed, while in a state of repose, and then stick their head underwater and rip pieces from their piscine prize (the bear will raise its head to masticate and then submerge to take another bite).

I have noticed that in many cases the fish rarely struggle much after being trapped in the bear’s jaws. They seem to go limp. They may flop about if the bear should drop them on the shore before pinning them down to eat, but otherwise they resist very little while in the jaws of the bruin. (I did see occasions where they fish would struggle if a bear bit down on the upper back.)

In the video featured below, you will see various fishing methods and some of these handling methods employed by a number of different Katmai brown bears. A few things to look for: there is a sequence of video that shows a big brown bear deftly removing the brain from a fish. There is a scarred, big boar diving into a deep river pool from the shoreline and submerging in an attempt to capture its slippery quarry (he finally succeeds in capturing a "spent" fish in the video and stands on its hind feet as it tears the fish apart). Toward the end of the video, you will see a large boar launching some of its great bulk from the river and plunging back into the water with fore legs outstretched. At one point, it has herded a big school of salmon along the river bank and appears to be trying to push some of the fish onto the shoreline. Turn up the sound and enjoy!

video

© Scott W. Michael