WILL YOU HEAR?
and MARINAS: Take a trip to your local marina;
drop Dolphin- EAR into the water. Try to get near the entrance. If you
are near a major port, try within 300-400 metres of the ship berths and
listen as they maneuver. Each boat or ship has it's own characteristic
sound. Often you can hear which ones are having mechanical problems with
their engines, prop shafts and propellers. You will also hear a lot of
Snapping Shrimp (discussed below)
best place! If you are looking for Dolphins or Whales, go to the areas
they frequent. Shut off the boats' engine and listen. Usually, you can
hear their vocalizations on the DolphinEAR before you actually see them!
Don't take your boat too close. They will come to you! Meanwhile enjoy
their grunts, whistles and songs.
WATCHING TOURS: Great fun! A good operator
will be able to find the best locations. If you are shooting a video, plug
DolphinEAR into the camera so you can HEAR and SEE the whales. Plus, you
will be able to hear whales as they dive for food - often out of view for
long periods but within range of your DolphinEAR!
you are getting a little 'surface time' between dives, put the DolphinEAR
hydrophone over the side and listen for the sounds of the sealife around
you. It's useful as a signal between divers and dive boat, too!
the BEACH: Try a wharf, pier or dock that gets
you away from the breaking waves of a beach. In some northern climes, you
may hear the grunts of seals living nearby.
and RIVERS: Nearly anyplace will do. Listen
for boats, or in the winter try listening for the sounds made by Ice as
it cracks and groans.
Some places are very quiet;
some a sonically 'alive'. You will have to experiment to find the best
places. While listening to whales and dolphins is lots fo fun, there are
many other creatures which make sounds underwater. Remember also, that
before DolphinEAR came along, listening to underwater sounds was an expensive
and time consuming proposition. You may discover underwater sounds that
have never been heard! You may also find links between sounds and various
habitats. For example, we wonder why 'snapping shrimp' seem to prefer boat
marinas where pollution and toxic bottom paints abound, over cleaner waters
just outside the entrance. If you want to explore our last earthly frontier,
DolphinEAR will open up a whole new dimension.
You will often hear dolphins
when you cannot see them. They are easily identified by their high pitched
squeeks. They also emit a 'clicking' sound used to locate fish. Sometimes
they are very quiet and even though they are close to your boat you won't
hear much. Other times, you can hear them through the boats' hull! Whales
are generally identified by lower pitched grunts and moans.
You will probably hear more
than you will see with whales. Listen to whales as they dive and search
for food. Different whale specied tend to emit different noises and scientists
are trying to determine the exact meaning of the different sounds. This
is an area where 'amateur scientists' using a DolphinEAR can contribute
greatly to the general knowledge about the meaning of these 'vocalizations'.
Listen for the crackling
and popping of 'Snapping Shrimp'. They seem to thrive in most marinas and
in many bays and anchorages. They create a snapping noise with their large
claw. Scientists disagree as to the purpose of the snapping. Some say it's
a warning to other shrimp nearby. Others say the shrimp shoot out a jet
of water from their claw to stun prey. Whatever the reason the snapping
goes on day and night. You will also hear a lot of boats. Listen for the
different sounds made by sailboats, power boats, Jet Skis, and different
outboard motors on dinghys. With practice you can pick out whether a boat
uses a diesel or petrol power engine, hear pumps, and bubbles from outboard
exhausts. Some boats are very quiet and you can only hear them at a range
of 30-50 metres. Some are lounder and you can har them out to 1/2 kilometre
and Dugongs (Manatees):
Both make underwater sounds
but not much has been recorded or described in scientific literature. A
Dugong nursing pups will call them over distances of a few hundred metres.
There is much work to be done recording and cataloging these 'vocalizations'.
Many fish can make sounds.
There are 'Croaker Fish' which as the name implies make 'croaking' sounds.
There are species of coral dwelling fish that make sounds by gnawing on
coral - perhaps to scare preditors or attract mates. Large Groupers make
'grunts' to signal theiir displeasure at your presence. There may be many
more if we start looking for them. Again, this is an excellent place for
the amateur scientist to make meaningful contributions to marine science.
Large ships generate very
low frequency sounds and vibrations which can sometimes be picked up several
miles away. Many factors are involved including speed and direction of
the boat. If you are near a port, try listening to a ship as it maneuvers
into its berth. Getting within 200 - 300 metres should allow you to have
a good listen as tug boats grind their engines and the ship thrusts forward
and backwards to position itself at the wharf.
When you get out from the
shore on a boat, many of the interfering sounds found close to shore disappear
and you are able to hear sounds much further away.