Kind: captions
Language: en
you're watching the nova video podcast
certain areas in the bering sea we call
hot spots there's areas where we get a
congregation of animals
we see congregations of clams and then
there's congregations of walruses that
are going after them
over the last 10 to 15 years we've been
seeing major declines in the food the
prey which are the clams the worms on
the bottom particularly the clams that
are the food for these diving threatened
sea ducks the spectacle dieter but
they're also a major food supply for
walruses
the healey scientists can be certain
about this decline in the food chain
because every year they've taken samples
in the exact same locations
at each research station they check the
chemistry and biology of the ice the sea
water and the benthic layer what most of
us call the ocean floor
i got it
yeah
put your hands on the bottom
over the years we've had cruises
anywhere from march through october
we work 24 7 which means for 24 hours a
day seven days a week we have teams that
are always working
right now we're in the northern bering
sea
between alaska and russia
it's the area where we do a bottom
sampling so we're sampling for mud
animals at the bottom of the ocean
we are out on the deck and we use a grab
which is a mud templars like a clam
dredge and we get a certain area
of the mud and we grab it bring it up
we open that jaw and we drop out the mud
and spray it out
and bring it over to a sieve and we use
a certain size sieve or you know opening
like you would strained spaghetti and we
strain out the mud and keep the animals
it's always interesting because you
never know what you bring up with the
grab um maybe there's something special
in there and maybe it looks like the
other stations
i mainly look for those organisms who
feed on the ice algae copper pots and
krill for example and see if the
isotopes from that tissue tell me
what kind of food source they they have
you can see a lot of
shells of by valves
a lot of species of olights
and what else
ah this is a big big polycats
and nafties
very
nice and very delicious
for walruses maybe
walruses have eaten well from the bering
sea and so have we
the bearing is the world's most
productive commercial fishery and has
been for over a century
the world has consumed millions of tons
of its herring and cod and an astounding
amount of that most dangerous catch
crab
most recently the principal catch has
been the main ingredient in the
ubiquitous fast food fish fillet pollock
but can the bearing continue to offer
such fishy bounty forever
the bering sea is warming
what we're trying to do is to understand
how this system which is shallow it's
vulnerable how it's going to respond and
change what's going to happen here in
dutch harbor which is a big fishing port
there's some impacts on the economy here
there's some impacts further north where
we're going the people that live there
depend upon the bering sea as a food
resource and uh they're very concerned
about climate change and what impact
that's going to have on the organisms
that they hunt
walrus or bowhead whale
bearded seal so forth
our main concern is that
our ice condition is losing its
thickness its density through the ears
as you can see if
if the camera can see also the far end
of the water here with that ice
you can see how thin it is actually
from an ecosystem perspective the bering
sea and the chukchi sea are very rich
habitats for animals feeding on the
benthas like the grey whale or like the
walrus
and this is largely due to the impact of
the sea ice seasonal melt produces a
huge phytoplankton plume
and that sinks all to the sea floor
and the animals at the seafloor use it
and they are the food then for the
walrus and for the gray whale
now there is there is the concept around
that if we remove the sea ice too early
then that plume of phytoplankton that
happens in the water might be consumed
totally in the water column and might
not reach the sea floor
and so that would mean that all these
benthic feeders like the walrus and the
gray whale might run out of food
implications that are currently
discussed for biologists are are really
reaching pretty far from extinction of
species to entire ecosystem changes and
for many regions in the arctic we just
don't have any idea about the current
status and the current situation
you