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$Unique_ID{bob01001}
$Pretitle{}
$Title{Glacier Bay
'So Far As Known'}
$Subtitle{}
$Author{Kirk, Ruth}
$Affiliation{National Park Service;U.S. Department Of The Interior}
$Subject{glacier
ice
inlet
water
black
pup
bay
bears
far
fish}
$Date{1983}
$Log{}
Title: Glacier Bay
Book: Part II: Of Time And Ice
Author: Kirk, Ruth
Affiliation: National Park Service;U.S. Department Of The Interior
Date: 1983
"So Far As Known"
Field notebooks of summers in the 1970's document hour-by-hour seal
behavior in Johns Hopkins and Muir Inlets. Summer park biologist John
McConnell:
"16 June, 2:14 p.m. Earthquake tremor! Two second duration. Ground
shook. Rocks fell off north side of Inlet. Seals calling all over now. Not
much diving in. Just up, looking around, pretty loud boom that echoes. No
calving on either Muir or Riggs.
"2:34 p.m. Lost pup has been swimming around calling for about 10
minutes. Hauls out. Back in, and goes on swimming and calling frantically.
No one seems to care. One really LOUD call, almost scream.
"2:42 p.m. Pup really frantic, one single adult in water about 60 yards
away looking around and raising out of water to look. Could this be the
negligent mother?
"2:45 p.m. Lost pup comes up to mother-pup pair on berg, calling. Looks.
They don't even wake up.
"2:48 p.m. Single adult swimming in direction of lost pup.
"2:50 p.m. Come together, bump noses, pup shuts up and they dive, come
up, now swimming off to north. Crisis ended.
"17 June, 4:20 p.m. Mother and two pups playing; they all ball up and
roll over and over, then dive, come up, and do it again. Both pups alternate
hitching rides on her back till she rolls them off. Mother goes to each and
bumps noses.
"4:24 p.m. Here comes a single adult toward the threesome. Goes to one
pup, touches noses. Now swims off with that pup. Other female and pup go in
different direction. Was it a Muir Inlet baby sitting service I watched a
moment ago?"
Former park biologist Greg Streveler one summer counted 3,500 seals in
Johns Hopkins Inlet. Nearly a third that many ride the floating ice of upper
Muir Inlet. When glaciers were still discharging bergs into Wachusett and
Adams Inlets, seal pupping took place there as well, but the pupping went out
with the ice. Hair seals congregate in their pupping grounds from May to
August where the pack ice is thickest. Seals probably adapted to pupping on
floating ice only since the last glacier retreat; before that pupping on
beaches and rocky islets. Greg explains why biologists think this:
"Seals hauled out onto ice seem to worry more about what's going on along
the shore than what's happening in the water nearby. A man on the beach, even
150 meters (500 feet) away, will panic mothers and pups into diving off their
bergs. But once they're in the water their terror eases. The animals seem
genetically coded to be more wary of trouble coming from the land than from
the water. They must have moved to floating ice as an escape from shore
predators but they haven't yet perfected new behavior to go with the habitat."
Greg also says that the mother's pattern of searching for her separated
pup would work far better along the fixed shore than it does in the shifting
realm of floating ice. Indeed, this is the weak point in mother-pup bonds.
Lost pups soon become dead pups. People should never approach seals closer
than 50 meters (160 feet) during the critical early weeks of pupping in
mid-May to late June. Killer whales supposedly hair seals' greatest enemy,
don't go to the heads of Johns Hopkins or Muir Inlets. It is ironic that
people, armed only with cameras and often good intentions should pose such a
threat.
"It's being startled that has the grave implications," Greg says.
"That's what leads to separation,"
Geike Inlet
We've anchored inside Geike Inlet, where Chess immediately rigged his
pole and cast from Taku's cockpit. He said he'd add this spot to his world
map of places he's caught no fish. I've just rowed back from watching salmon
by the thousands struggle up the creek to spawn in freshwater. They rarely
feed while spawning.
Salmon spawning is a spectacle: Carcasses line the creek banks heads a
sepulchral white, hooked jaws still full of needle teeth, eye sockets empty,
Live fish thrash against the water's flow, backs above the surface, wriggling
like snakes, forcing passage over cobbles. Sometimes they turn on their sides
and slither up shallow riffles. Pale underbellies show. Yellow eyes seem
strained and desperate.
Once a sudden movement and a loud splash made me pivot to look. A huge
male had wedged headdown between two rocks, caught by water pouring forcefully
over a log. I watched his struggle, then looked away. When I turned back,
he'd broken free. I counted 33 fish in a 3-meter (10-foot) radius. This
entire cove was deep beneath ice 150 years ago. When the glacier began to
wane, runoff streams must have carried more silt than fish tolerate, When did
the salmon arrive?
Once Louis and I joined Ole Wik in checking on whether Dolly Varden had
returned to a stream at the head of Geike Inlet, not far from Shag Cove. My
journal of that trip with Ole records:
"We sit in the dinghy halfway to shore, attention riveted on a half-grown
wolf pup that trots from where it was feeding. It watches us from the
willows, secure within their protective screen although keeping ears cocked
like twin radars.
"After a while, the pup moves on, then returns with a second pup. Both
are black, typical of wolves in Glacier Bay - and not an unexpected color, for
wolves as a whole vary from sand-colored, through almost red, to this decided
black. The two pups stand curious, but unconcerned. For once, there is time
to focus binoculars and fix a sight indelibly in mind.
"While the wolves stare at us, a whale rolls barely astern of our
anchored boat. It blows, smacks the water with a flipper so long it's like a
wing; then the whale submerges. The sudden slap against the water startles
200 to 300 crows into circling as a ragged black cloud, cawing wildly. Their
racket prompts a bald eagle into lifting off from somewhere so far back in the
spruce that we wouldn't have noticed it if it hadn't flown.
"Where but Glacier Bay can you swivel binoculars and find such a
three-minute sequence of land, sea, and air life as prelude for a stream
check? We find no Dolly Varden, however. Maybe conditions aren't yet right.
Maybe our seasonal timing is off."
Glacier streams raging across raw outwash plains attract no salmon. But
in time as stream conditions mature, fish find their way. With them a whole
chain of life is fostered. Eagles, ravens, and coyotes feed on spawned-out
salmon carcasses littering the banks. Mink and otter, wolves, black bears and
brown/grizzly bears take live fish. Seals foray into stream mouths to feed on
spawners newly arrived at homewater.
Four Pacific salmon species spawn here: silver chum, sockeye, and pink.
Dolly Varden, steelhead, cutthroat, and three-spined stickleback also spawn in
Glacier Bay's freshwater. King salmon frequent Bartlett Cove, Berg Bay, and
Dundas Bay, but do not yet enter streams to spawn, s.f.a.k. - "so far as
known," as field naturalists a century ago acknowledged the limits of their
knowledge.
Details can prove fascinating. In some Glacier Bay streams snails and
bivalves are few because the water is too low in dissolved minerals for the
making of shells. Shells are mostly calcium carbonate. On the other hand,
tiny shrimplike creatures thrive in ephemeral ponds fed by melt from glacier
remnants. Their eggs don't dry out readily and will pass unscathed through
the guts of fish or birds. In fact, viable eggs have been found in the feces
of fish-eating birds. This means the eggs have endured a double dose of gut
acids, first the fish's, then the bird's!