Multimedia Mania/abacus-multimedia-mania.iso/dp/0100/01001.txt

Text File | 1993-07-27 | 22KB | 377 lines

$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!

     Birds bring crustaceans to newly formed ponds.  Insects come on their
own, to streams as well as ponds.  The aquatic nymphs of mayflies, stoneflies,
and caddisflies are equipped with bristles, hooks, and suckers for clinging to
rocks, so rushing water is no problem.  Various biting flies are equally able
to survive immature stream conditions.  Even close to melting ice in water too
cold, rushing, and silt laden for other species, blackfly larvae secure
themselves to rocks by hooking their tails into specially secreted silken
pads.  "No-see-ums," perpetrators of painful bites in their adult stage, also
flourish in glacial torrents.  Ashore in summer, you scarcely escape their
swarming attack anywhere.  Afloat you are safe.

     "A sinuous strip a quarter of a mile wide on the landward side of the
beach and double that to the sea is where the action is" Greg Streveler says.
We owe the variety and abundance of wildlife in the park to this shoreland
strip.  The shore is the land mammal's larder because it links the sea's
riches to life on land.  Red foxes feed along the beach on ducks, sand fleas,
gooseneck barnacles, dead fish, beached whales, fledglings strawberries.
Coyotes crunch open sea urchins and mussels.  Greg once watched a brown/
grizzly bear dig clams on the outer coast, "sand and rocks really flying, its
butt sticking up out of the hole."  Black bears squish open barnacles to eat.
Shrews feast on barnacles, mussels, and squashed snails.  Mountain goats and
porcupines eat seaweed.  Deer do too, but they can't digest it; deer have
starved to death here, their stomachs full of seaweed.  Sedges and grasses,
available even in winter, bring the deer and goats to the shore.  Seaweed is
just a salty sidedish.

     Shorebirds join the beach community while retreating glacier fronts are
still closeby and floating bergs a constant presence.  Oystercatchers - the
size of northern crows, black with naked pink legs like stilts, and with
bright orange, chopstick bills - are my favorites.  They eat not oysters, but
snails and mussels.  Louis and I camped at Reid Inlet once and filmed
oystercatcher hide-and-seek among small, stranded icebergs.

     It was a gray June week with the mists clamped to the water.  Sky and
sea, equally wet, differed only in texture: the water polished, the clouds
dull.  For brief periods when the murk thinned we could make out a vee of
scoters flying low to the water in one direction.  Glaucous-winged gulls,
higher, moved in the opposite direction.  Or a fleet of pigeon guillemots
might be bobbing as if at anchor, each bird a solid black fore and aft but
with white wing patches separating end from end.  When the guillemots dove
after fish, their red legs and feet flashed a momentary finale to the
upending.

     Mew gulls and arctic terns nested on the foreshore, their eggs laid in
saucer-shaped scrapings ungraced by grass, down, or other softening material,
Gulls returning to brood duty often first landed on an iceberg to look around,
their touchdowns like the uncontrolled skids of neophyte ice skaters. Arctic
terns defended nests by dive-bombing and cursing intruders.  Their targets
included Louis and me, mew gulls, and the oystercatchers, which cringe
comically when a tern zeroes in.

     Louis and I knew that a pair of oystercatchers nested near the gulls and
terns, but where?  Both male and female stalked about glancing back to be sure
we were fooled about where their nest was.  Satisfied we were still watching,
they then crouched and squirmed as though settling onto eggs.

     One morning I chanced upon the two oystercatchers apparently at their
real nest, well back from the highest strand line.  They saw me see them.
Looking chagrined and uncertain of what to do, they just shrieked and flew
off.  I retreated, stepping only on large flat stones to avoid crushing eggs I
couldn't see.  Their spotted shells blend perfectly with the rock mosaic left
by a retreating glacier.

     Arctic terns commute from Antarctic wintering grounds to Glacier Bay,
arriving in May while snow still covers the ground.  They are gone again by
mid-August.  To disrupt such hurried nesting and fledging would be
unconscionable.  The National Park Service grew concerned when the present
large cruise ships began entering the bay.  Excursion steamers of the late
1800's were much smaller.  When the 33,000-ton Arcadia first arrived in 1970,
rangers watched beaches to see what the ship's wake might do.  A single errant
wave could destroy nests and nullify the terns' 32,000 kilometer (20,000 mile)
round-trip journey.

     Fortunately a ship moving slowly did no harm - probably less than our
human presence ashore, no matter how carefully we stepped and stayed back
photographing with long lenses.  People are decidedly disturbing to wildlife.
Wolves seem reluctant to trot their accustomed paths while people are around,
though their scat shows they're still about.  Mountain goats will abandon the
whole side of a ridge facing a camp far below them.

     That same summer of oystercatcher hide and seek Louis and I filmed at the
Ohio State University research camp in Wachusett Inlet.  Camp was a moonscape
with ice.  Tents sprouted from a bare moraine, icebergs floated past, and a
kilometer (half mile) behind camp the stagnant Burroughs Glacier melted into
oblivion.  It shrank scores of meters (hundreds of feet) per year, its ice so
brown with rock and silt that it hardly looked like a glacier.  But
terrestrial life had already begun staking a claim.

     Snow buntings, trim white-bellied finches, came mornings to feed on
iceworms, which look like wriggling bits of black thread.  These distant
relatives of earthworms live their whole lives in ice.  There they feed on
algae and bacteria, and on organic matter and minerals washed along by glacier
melt and borne by air currents.  The first such worms reported anywhere - in
1877 - came from the Muir Glacier.  We now know iceworms occur widely in the
coast mountains from Washington northward.  A few years ago, Ohio State
researchers flew iceworms home with them from Glacier Bay and maintained them
in the laboratory for more than a year.  In the esophagi of several, they
found cylindrical micro-organisms which may secrete an enzyme that helps them
digest algae.  You never know where you'll find the base of a food chain.

     One of the glaciologists found a dead shrew beneath the Burroughs Glacier
when he roped down a cavernous melthole to trace water channels.  Far out on
the glacier taking measurements, two men were buzzed by a rufous hummingbird
and several times saw bumblebees.  Deer mice plagued the Wachusett camp at
night.  A tundra vole sampled every candy bar in one particular sack.

     How can tiny rodents, hummingbirds, or bees brave the glacier barrens?
Resilience and adaptations.  Hummingbird metabolism permits a sustained energy
output impossible among mammals.  Bumblebees, far from hapless victims of
environment, can control body temperature.  Hike across a glacial outwash such
as the one that spills from the Casement Glacier and at the ice face you find
buntings pouring out territorial song from the sharp crests of eskers.
Ptarmigan droppings are evident too.  The birds blend so perfectly with rocks
and moss tufts that you rarely see them unless and until they move.

     Redpolls and rosy finches may be raiding willow catkins for seed and
picking insects from where scattered fireweed and alder pioneer the gravel.
Where dryas has started forming mats, Savannah sparrows and least sandpipers
nest.  In alder and willow thickets, hatchlings of orange-crown warblers, fox
sparrows, and even occasional hermit thrushes and Oregon juncos harass parents
to supply what must seem like endless food.  Feathers and flight muscles are
made of mosquitoes, blackflies, midges, plant lice, and water beetles.

     Glacier Bay's bird list boasts more than 200 entries.  Included are
species more typical of Arctic tundras and Aleutian grasslands than of
southeast Alaska.  They are here because of the glaciers.  As vegetation
sequences progress to the hemlock stage, these birds of the barrens largely
forsake the park, replaced by forest species.  On the Bartlett Cove trails you
hear the plaintive, minor call of varied thrushes and the musical notes of
Swainson's and hermit thrushes, birds common throughout Northwest rain
forests.  Robins are present, their singing - to my ear - like that of a
cheerful amateur determined to learn to carry a tune.  Kinglets and siskins
flit through tree tops in loose, lisping flocks.  Three-toed woodpeckers and
blue grouse sound their territorial claims, the woodpecker by pounding a dead
tree, the grouse by releasing air from throat sacs.

     Spring and fall migrations bring birds in, out, and through the park in
the ebb and flow of an avian tide.  Loons by the thousands stream north along
the outer coast in spring.  Squadrons of northern phalaropes fly low to the
sea in early summer, dropping to feed in tide rips.  With winter, old squaw
ducks and common murres by the tens of thousands arrive in Glacier Bay, much
of their food needs supplied by seabottom dwellers.  The shore's mingled
sea-and-land resources are crucial for birds as well as land mammals.

     One misty Reid Inlet morning Louis and I noticed a small dark dot
swimming our way from the far shore.  At first we supposed it a seabird, then
a seal.  On it came, purposefully, straight toward our tent.  Within minutes
we watched a black bear step onto the beach, shake half dry, and amble from
view.

     Land animals aren't commonly so close to ice but they don't wholly avoid
glaciers.  In the shrinking wedge of rubble and runoff that separates the
Margerie and Grand Pacific Glaciers, hikers have found brown/grizzly bear and
lynx tracks.  In Johns Hopkins Inlet, Greg once found evidence of a wolf.  For
a while there were mice close to the glacier front, probably stowaways in
campers' gear.  Marmots eke out an existence near Reid Inlet's entrance, their
shrill whistle a surprise coming from near sea level because these plump
woodchuck-cousins are highcountry characters throughout the West.  The
elevation seems wrong, but the biome is right.

     Land mammals face their own problems in moving back to newly ice-free
shores and lowlands.  They can't come by air, as the first plants do with
windblown seeds and spores, or as the first insects do, arriving as winged
adults or in bird gullets.  Mammals must walk or swim.  Even for large
animals, extensive ice or water or mountains may be a formidable barrier.

     The two sides of Muir Inlet exemplify the land mammals' disadvantage.
Plant succession shows no real difference between sides of the inlet, nor do
insect or bird populations.  However, the east side hosts several more species
than the west.  From the east side a low pass connects from Adams Inlet to
Lynn Canal and so to the interior.  But the west side of Muir Inlet has no
such conduit outside.  Bounded by ice, mountains, and more saltwater, it is,
from the standpoint of life, an island hard to reach.

     No true successional stages characterize mammals' pursuit of waning ice,
No pioneer species regularly prepare the way for replacements, as with plants.
Large mammal firstcomers usually draw on the resources of ecologically young
terrain part of the year, moving elsewhere the rest of the year.  Gradually,
resident populations will build.  Moose were first seen in the lowlands east
of Muir Inlet in the 1950's, probably having come over Endicott Pass from Lynn
Canal.  Now you often see moose, or moose sign.  Moose have begun to round
Tlingit Point into lower Tarr Inlet and have spread throughout the western
park, recently to Dundas Bay.

     This is also a barrier: mammals haven't had time since the Wisconsinan
Ice Age to complete their dispersal throughout southeastern Alaska.  The white
shroud of the glacial maximum covered most of the region below 600 to 700
meters (2,000 to 2,300 feet) elevation, but it left refugia - green arks of
continuing life - north and south of the ice sheet.  Brown/grizzly bear,
moose, muskrats, and snowshoe hares have repopulated southeastern Alaska from
such northern refugia, so far as known.  Black bear, wolf, coyote, deer, and
mountain goat have come from refugia to the south.  Mountain slopes in the
Glacier Bay region also provided sky islands of livable habitat for small
creatures during the Ice Age.  And minor refugia along the park's outer coast
escaped getting swallowed by ice during the whole of the Wisconsinan glacier
advance.  Today 28 mammal species are listed for the park.

     Greg Streveler speculates that one or more coastal refugia may have been
large enough for the so-called glacier bears to develop as a distinct race of
black bears.  Their coats took on a distinctive steely blue color.  Indians
and 19th-century settlers describe these bears as different from black bears
and brown/grizzly bears both in looks and behavior.  They stayed apart from
the other bears, preferring the glacier barrens they probably grew accustomed
to during the Ice Age.  Glacier bears never became a species of their own,
however, and now they've bred back into the black bear population.  Even the
blue-gray coat appears less and less often.

     It's said that only iceworms and glaciologists suffer when the ice sheets
disappear.  We should add glacier bears to the list.  The surest place to see
one now is the Juneau Museum.