How human noise affects ocean habitats
-
0:01 - 0:06In 1956, a documentary
by Jacques Cousteau won -
0:06 - 0:09both the Palme d'Or and an Oscar award.
-
0:09 - 0:12This film was called,
"Le Monde Du Silence," -
0:12 - 0:14or, "The Silent World."
-
0:14 - 0:20The premise of the title was that
the underwater world was a quiet world. -
0:20 - 0:23We now know, 60 years later,
-
0:23 - 0:26that the underwater world
is anything but silent. -
0:27 - 0:30Although the sounds
are inaudible above water -
0:30 - 0:33depending on where you are
and the time of year, -
0:33 - 0:39the underwater soundscape can be as noisy
as any jungle or rainforest. -
0:40 - 0:45Invertebrates like snapping shrimp,
fish and marine mammals -
0:45 - 0:46all use sound.
-
0:46 - 0:49They use sound to study their habitat,
-
0:49 - 0:52to keep in communication with each other,
-
0:52 - 0:53to navigate,
-
0:53 - 0:55to detect predators and prey.
-
0:56 - 1:01They also use sound by listening
to know something about their environment. -
1:01 - 1:04Take, for an example, the Arctic.
-
1:04 - 1:07It's considered a vast,
inhospitable place, -
1:07 - 1:10sometimes described as a desert,
-
1:10 - 1:13because it is so cold and so remote
-
1:13 - 1:15and ice-covered for much of the year.
-
1:15 - 1:17And despite this,
-
1:17 - 1:21there is no place on Earth
that I would rather be than the Arctic, -
1:21 - 1:25especially as days lengthen
and spring comes. -
1:25 - 1:30To me, the Arctic really
embodies this disconnect -
1:30 - 1:35between what we see on the surface
and what's going on underwater. -
1:36 - 1:41You can look out across the ice --
all white and blue and cold -- -
1:42 - 1:43and see nothing.
-
1:44 - 1:46But if you could hear underwater,
-
1:46 - 1:50the sounds you would hear
would at first amaze -
1:50 - 1:52and then delight you.
-
1:52 - 1:56And while your eyes are seeing
nothing for kilometers but ice, -
1:56 - 2:01your ears are telling you that out there
are bowhead and beluga whales, -
2:01 - 2:04walrus and bearded seals.
-
2:05 - 2:07The ice, too, makes sounds.
-
2:07 - 2:10It screeches and cracks
and pops and groans, -
2:10 - 2:15as it collides and rubs when temperature
or currents or winds change. -
2:16 - 2:20And under 100 percent sea ice
in the dead of winter, -
2:21 - 2:23bowhead whales are singing.
-
2:24 - 2:26And you would never expect that,
-
2:26 - 2:28because we humans,
-
2:28 - 2:31we tend to be very visual animals.
-
2:31 - 2:34For most of us, but not all,
-
2:35 - 2:37our sense of sight is how
we navigate our world. -
2:38 - 2:40For marine mammals that live underwater,
-
2:40 - 2:44where chemical cues
and light transmit poorly, -
2:44 - 2:48sound is the sense by which they see.
-
2:48 - 2:51And sound transmits very well underwater,
-
2:51 - 2:53much better than it does in air,
-
2:53 - 2:56so signals can be heard
over great distances. -
2:56 - 2:59In the Arctic, this
is especially important, -
2:59 - 3:03because not only do Arctic marine
mammals have to hear each other, -
3:03 - 3:06but they also have to listen
for cues in the environment -
3:06 - 3:10that might indicate
heavy ice ahead or open water. -
3:11 - 3:14Remember, although they spend
most of their lives underwater, -
3:14 - 3:16they are mammals,
-
3:16 - 3:18and so they have to surface to breathe.
-
3:18 - 3:22So they might listen
for thin ice or no ice, -
3:22 - 3:25or listen for echoes off nearby ice.
-
3:27 - 3:32Arctic marine mammals live in a rich
and varied underwater soundscape. -
3:33 - 3:34In the spring,
-
3:34 - 3:36it can be a cacophony of sound.
-
3:37 - 3:41(Marine mammal sounds)
-
3:53 - 3:56But when the ice is frozen solid,
-
3:56 - 4:00and there are no big temperature
shifts or current changes, -
4:00 - 4:04the underwater Arctic has some
of the lowest ambient noise levels -
4:04 - 4:06of the world's oceans.
-
4:06 - 4:07But this is changing.
-
4:07 - 4:11This is primarily due to a decrease
in seasonal sea ice, -
4:12 - 4:15which is a direct result of human
greenhouse gas emissions. -
4:16 - 4:19We are, in effect, with climate change,
-
4:19 - 4:23conducting a completely uncontrolled
experiment with our planet. -
4:24 - 4:26Over the past 30 years,
-
4:26 - 4:30areas of the Arctic have seen
decreases in seasonal sea ice -
4:30 - 4:34from anywhere from
six weeks to four months. -
4:35 - 4:39This decrease in sea ice is sometimes
referred to as an increase -
4:39 - 4:41in the open water season.
-
4:41 - 4:45That is the time of year when
the Arctic is navigable to vessels. -
4:46 - 4:48And not only is the extent
of ice changing, -
4:49 - 4:53but the age and the width of ice is, too.
-
4:53 - 4:55Now, you may well have heard
-
4:55 - 4:58that a decrease in seasonal sea ice
is causing a loss of habitat -
4:58 - 5:00for animals that rely on sea ice,
-
5:00 - 5:04such as ice seals,
or walrus, or polar bears. -
5:05 - 5:10Decreasing sea ice is also causing
increased erosion along coastal villages, -
5:10 - 5:13and changing prey availability
for marine birds and mammals. -
5:14 - 5:17Climate change and decreases in sea ice
-
5:17 - 5:22are also altering the underwater
soundscape of the Arctic. -
5:23 - 5:25What do I mean by soundscape?
-
5:26 - 5:29Those of us who eavesdrop
on the oceans for a living -
5:29 - 5:31use instruments called hydrophones,
-
5:31 - 5:33which are underwater microphones,
-
5:33 - 5:35and we record ambient noise --
-
5:35 - 5:37the noise all around us.
-
5:37 - 5:40And the soundscape describes
the different contributors -
5:40 - 5:42to this noise field.
-
5:43 - 5:45What we are hearing on our hydrophones
-
5:45 - 5:49are the very real sounds
of climate change. -
5:50 - 5:52We are hearing these changes
from three fronts: -
5:53 - 5:55from the air,
-
5:55 - 5:56from the water
-
5:56 - 5:57and from land.
-
5:58 - 6:01First: air.
-
6:02 - 6:05Wind on water creates waves.
-
6:05 - 6:06These waves make bubbles;
-
6:06 - 6:08the bubbles break,
-
6:08 - 6:09and when they do,
-
6:09 - 6:11they make noise.
-
6:11 - 6:14And this noise is like a hiss
or a static in the background. -
6:15 - 6:18In the Arctic, when it's ice-covered,
-
6:18 - 6:22most of the noise from wind
doesn't make it into the water column, -
6:22 - 6:27because the ice acts as a buffer
between the atmosphere and the water. -
6:27 - 6:28This is one of the reasons
-
6:28 - 6:32that the Arctic can have
very low ambient noise levels. -
6:33 - 6:35But with decreases in seasonal sea ice,
-
6:35 - 6:40not only is the Arctic now open
to this wave noise, -
6:40 - 6:44but the number of storms
and the intensity of storms in the Arctic -
6:44 - 6:45has been increasing.
-
6:46 - 6:50All of this is raising noise levels
in a previously quiet ocean. -
6:51 - 6:53Second: water.
-
6:54 - 6:56With less seasonal sea ice,
-
6:56 - 6:59subarctic species are moving north,
-
6:59 - 7:04and taking advantage of the new habitat
that is created by more open water. -
7:05 - 7:08Now, Arctic whales, like this bowhead,
-
7:08 - 7:09they have no dorsal fin,
-
7:09 - 7:14because they have evolved to live
and swim in ice-covered waters, -
7:14 - 7:18and having something sticking
off of your back is not very conducive -
7:18 - 7:19to migrating through ice,
-
7:19 - 7:23and may, in fact, be excluding
animals from the ice. -
7:24 - 7:26But now, everywhere we've listened,
-
7:27 - 7:30we're hearing the sounds
of fin whales and humpback whales -
7:30 - 7:31and killer whales,
-
7:31 - 7:33further and further north,
-
7:33 - 7:35and later and later in the season.
-
7:36 - 7:37We are hearing, in essence,
-
7:37 - 7:41an invasion of the Arctic
by subarctic species. -
7:42 - 7:44And we don't know what this means.
-
7:44 - 7:49Will there be competition for food
between Arctic and subarctic animals? -
7:49 - 7:54Might these subarctic species introduce
diseases or parasites into the Arctic? -
7:55 - 7:58And what are the new sounds
that they are producing -
7:58 - 8:00doing to the soundscape underwater?
-
8:01 - 8:03And third: land.
-
8:03 - 8:05And by land ...
-
8:05 - 8:06I mean people.
-
8:07 - 8:10More open water means
increased human use of the Arctic. -
8:11 - 8:13Just this past summer,
-
8:13 - 8:17a massive cruise ship made its way
through the Northwest Passage -- -
8:17 - 8:20the once-mythical route
between Europe and the Pacific. -
8:21 - 8:28Decreases in sea ice have allowed
humans to occupy the Arctic more often. -
8:28 - 8:33It has allowed increases in oil
and gas exploration and extraction, -
8:33 - 8:35the potential for commercial shipping,
-
8:35 - 8:37as well as increased tourism.
-
8:38 - 8:43And we now know that ship noise increases
levels of stress hormones in whales -
8:43 - 8:45and can disrupt feeding behavior.
-
8:46 - 8:51Air guns, which produce loud,
low-frequency "whoomps" -
8:51 - 8:54every 10 to 20 seconds,
-
8:54 - 8:57changed the swimming and vocal
behavior of whales. -
8:58 - 9:03And all of these sound sources
are decreasing the acoustic space -
9:03 - 9:06over which Arctic marine mammals
can communicate. -
9:07 - 9:11Now, Arctic marine mammals
are used to very high levels of noise -
9:11 - 9:13at certain times of the year.
-
9:13 - 9:17But this is primarily from other
animals or from sea ice, -
9:17 - 9:20and these are the sounds
with which they've evolved, -
9:20 - 9:23and these are sounds that are vital
to their very survival. -
9:23 - 9:27These new sounds
are loud and they're alien. -
9:27 - 9:32They might impact the environment
in ways that we think we understand, -
9:32 - 9:35but also in ways that we don't.
-
9:37 - 9:42Remember, sound is the most
important sense for these animals. -
9:42 - 9:46And not only is the physical habitat
of the Arctic changing rapidly, -
9:46 - 9:49but the acoustic habitat is, too.
-
9:49 - 9:53It's as if we've plucked these animals up
from the quiet countryside -
9:53 - 9:56and dropped them into a big city
in the middle of rush hour. -
9:57 - 9:58And they can't escape it.
-
10:00 - 10:02So what can we do now?
-
10:03 - 10:05We can't decrease wind speeds
-
10:05 - 10:09or keep subarctic animals
from migrating north, -
10:09 - 10:11but we can work on local solutions
-
10:11 - 10:14to reducing human-caused underwater noise.
-
10:15 - 10:18One of these solutions
is to slow down ships -
10:18 - 10:20that traverse the Arctic,
-
10:20 - 10:23because a slower ship is a quieter ship.
-
10:24 - 10:28We can restrict access
in seasons and regions -
10:28 - 10:32that are important for mating
or feeding or migrating. -
10:32 - 10:36We can get smarter about quieting ships
-
10:36 - 10:39and find better ways
to explore the ocean bottom. -
10:40 - 10:42And the good news is,
-
10:42 - 10:44there are people
working on this right now. -
10:46 - 10:48But ultimately,
-
10:48 - 10:51we humans have to do the hard work
-
10:51 - 10:55of reversing or at the very
least decelerating -
10:55 - 10:57human-caused atmospheric changes.
-
10:57 - 11:02So, let's return to this idea
of a silent world underwater. -
11:03 - 11:05It's entirely possible
-
11:05 - 11:08that many of the whales
swimming in the Arctic today, -
11:08 - 11:11especially long-lived species
like the bowhead whale -
11:11 - 11:15that the Inuits say can live
two human lives -- -
11:15 - 11:19it's possible that these whales
were alive in 1956, -
11:19 - 11:21when Jacques Cousteau made his film.
-
11:22 - 11:24And in retrospect,
-
11:24 - 11:28considering all the noise
we are creating in the oceans today, -
11:29 - 11:32perhaps it really was "The Silent World."
-
11:33 - 11:34Thank you.
-
11:34 - 11:37(Applause)
- Title:
- How human noise affects ocean habitats
- Speaker:
- Kate Stafford
- Description:
-
Oceanographer Kate Stafford lowers us into the sonically rich depths of the Arctic Ocean, where ice groans, whales sing to communicate over vast distances -- and climate change and human noise alter the environment in ways we don't understand. Learn more about why this underwater soundscape matters and what we might do to protect it.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 11:51
Brian Greene edited English subtitles for How human noise affects ocean habitats | ||
Brian Greene approved English subtitles for How human noise affects ocean habitats | ||
Brian Greene edited English subtitles for How human noise affects ocean habitats | ||
Camille Martínez accepted English subtitles for How human noise affects ocean habitats | ||
Camille Martínez edited English subtitles for How human noise affects ocean habitats | ||
Camille Martínez edited English subtitles for How human noise affects ocean habitats | ||
Leslie Gauthier edited English subtitles for How human noise affects ocean habitats | ||
Leslie Gauthier edited English subtitles for How human noise affects ocean habitats |