Flying Krill #4

from Tim Page

on board the Australian Icebreaker "Aurora Australis"

in the pack ice off the Shackleton Ice Shelf, eastern Antarctica

December 17 (9th day of Ramadan), 1999, 2pm

Hi to the students and staff of Block Island, Winthrop and Doyon Schools!

PRESENT POSITION: 64 degrees South Latitude, 105 degrees East Longitude

DIRECTION HEADING: 259 degrees

SHIP SPEED: 6 knots

DISTANCE FROM TASMANIA: 1972 nautical miles

DISTANCE TO DAVIS STATION, ANTARCTICA: 702 nautical miles

AIR TEMPERATURE: - 1.2 degrees Celsius

WATER TEMPERATURE: - 1.4 degrees Celsius

WIND SPEED: 17 knots

HUMIDITY: 95%

Hi there everyone. I thought I'd send a quick email before you all went on

your vacation. Well we've been very busy on board the ship since we got to

the pack ice. Every day we have shifts on the bridge of the ship, looking

for seals for our survey. A few days ago we finally got some good weather,

so we decided it would be a good day to fly in the helicopters. Yipee!!

Some of our seal survey we do from the air in big red and white choppers.

It's just amazing flying over the pack ice. There are huge slabs of white

sea ice, with dark leads of water in between them. Sometimes you can see

whales popping up between the ice floes to breath. There are also huge

icebergs, some very flat, like tables, and some sharp and pointy like a city

skyline. I flew over one the other day that was shaped just like a big,

blue volcano, and it even had a big hole in the middle like a real volcano,

where there were little bird footprints! It's much harder to count seals

from the air because they look smaller from high up and you go past them

pretty fast, so you really have to concentrate. I'm supposed to be flying

again in a couple hours, I can't wait.

Another exciting thing happened a few days ago, we went through a krill

swarm. Krill are the little shrimp-like animals that live in the ocean here

in huge numbers. Most everything here eats them, sea birds, fish, whales,

seals and penguins, so they are very important to the Antarctic ecosystem.

Some scientists are worried that the number of krill may be decreasing.

This could be due to the "ozone hole" over Antarctica. Ozone is a gas high

up in the atmosphere, and it helps to filter out nasty rays that come from

outer space. Sadly the amount of ozone is less now because people keep on

pumping stuff into the air that breaks it down. Because of this, more UV

light is hitting the earth and this could damage krill.

Anyway, back to the krill swarm. No-one has seen one for 3 years in this

part of the Antarctic, so Simon & Stevie (the krill biologists) were happy

when someone on the bridge spotted it. The whole sea was alive with

billions of krill (well, a lot, no-one actually tried counting them). The

sea looked like a giant orange shrimp soup. Hundreds of birds were gorging

themselves on this feast. So Simon and Stevie threw some hoop nets over to

catch some, so they can study them. They got lots and lots and were very

happy.

Simon and Stevie also use a trawl net to try and catch krill, which goes

much deeper. Do you remember Charlie Chowder, the globe trotting Clam from

Ipswich, Massachusetts? (If not, look on my website). Well he was feeling a

bit down, you see he missed being in the ocean. So Simon kindly offered to

send him down in the trawl net to revisit some old friends. Charlie was

very excited so Simon strapped him on hard to the net and flung him over the

side, all the way down to 120 metres under the surface! Now although Simon

is a nice guy, few things in life are free, so Charlie had to agree that

while he was down there he would try and convince some krill to swim into

the net, which he did successfully. I also tried to help catch some (no, I

did not go down in the net!). One day I went out in the inflatable rubber

boat amongst the ice floes with a small trawl net. I obviously lack

Charlie's eloquence, since I didn't manage to convince any krill to swim

into my net. I did however catch some water and some bits of ice, which I

have to tell you isn't that impressive in the middle of the pack ice in the

Southern Ocean!

Simon and Stevie now have 3 species of krill on board; Superba (the most

common kind of krill), Big Eye Krill (little guys) and Crystal Krill

(rarer). But that's not all they got. They got lots of really cool little

worms that look like swimming feathers! They also got big jelly fish, lots

of little insect like looking amphipods, and some ice fish. These ice fish

are amazing. Normally you would think that the blood of a fish that lived

in water always so cold would freeze solid and the fish would die, but these

little guys actually have anti-freeze in their blood to stops this!! They

also have almost no red blood cells to make their blood thinner and easier

to pump.

The cold effects everything here. Did you know that the largest animal that

lives only on the land in Antarctica is a flightless midge (like a fly) that

is only 10 millimetres long! The water is a much better environment to live

in here, since it never really gets much colder that about -2 degrees

Celsius, but the land can get all the way down to -70 degrees. That's just

too cold to live, so most animals that spend some time on land (or ice),

like penguins and seals, spend most of the time in the sea, where there is

also lots to eat.

There's one animal that endures extreme temperatures so it can have babies

(well, chicks not babies), and that is the Emperor Penguin. They are the

big tall penguins that look like waiters in fancy clothes. In fact, I like

them so much that I have a small tattoo of one on my shoulder (don't tell my

parents!).

The problem with Emperor Penguins is that they are so big that their eggs

take a long time to incubate, but in the Antarctic there is only a short

time of (relatively) warm temperatures, so the poor birds have to sit out in

the cold, keeping their egg warm. The female lays the egg and then goes off

to the sea to feed, leaving the poor old dad to balance the egg on top of

his feet so it won't freeze. He does this ALL winter, in incredibly cold

weather. The expectant dads all huddle together in huge packs to keep warm,

and they don't eat at all! Finally the mom returns after the chick is

hatched, with a meal of fish for their new chick. The 2 parents recognise

each other by the sound of their call. Then the poor old dad has a chance

to trudge for days across the miles of ice to get to the sea to have his

first meal in months. Some people (not me of course) might suggest that

womens liberation has gone a bit too far in the Emperor Penguin world.

In the past, all of the people who visited Antarctica were men. Women used

not to be allowed to come here at all. Happily this has now changed, but

there are still more men here than women. Last year, the leader of our

voyage was a woman, and this year the deputy voyage leader, Gerry, is too.

Only about 10% of the people who spend the winter in Antarctica at the

moment are women, but more than half of the scientists who come here for

summer are female. So, girls, start studying and maybe you can increase the

numbers down here!

RESEARCH QUESTION

-------------------------------

What can you find out about krill? What do they look like (why not draw a

picture)? How big are they? And, most important, what would happen if they

disappeared?

I hope everyone has a great vacation and holiday, and enjoy this special New

Year.

I have to go and get in a helicopter now. Byyyeee.

Tim