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Dolphins are the only whales occuring in the Black Sea: they
are smal-sized toothed whales (as compared to their relatives
such as sperm-whale or orca). At the same time, they are the
largest marine animals in the Black Sea; it may be worth reminding,
that dolphins are not fish, they are mammals - which means
that they they are viviparous, and feed their calves with
milk, and they use lungs to breath air. To breath they have
to coming up to the surface; at those moments we see their
backs emerging among waves, and often can hear sounds they
produce exhaling the used air. Dolphin's "nose"
- blow hole - is situated on the back of animal's head. Usually,
dolphins dive for only one to three minutes, but they are
capable of staying underwater for ten minutes, going down for dozens meters.
Sometimes going shipboard we can see dolphins get a place
in the bow wave and travel with it, jumping and playng in
the streaming surf. Dolphins love playing indeed, and that
is a character marking them as animals with complex behavior
and advanced brain: by means of games dolphin calves learn
signals, rules of communication and interaction within the
family school, hunting techniques, and many other tricks.
Apart from the useful training games of dolphins' kids, sometimes
it seems that dolphins just enjoy playing - for example we've
seen them playing "volleyball" with a big Rhizostoma
jellifish - punching it out of water with their muzzles.
Sounds produced by dolphins - sounds like whistles, snapping,
trilling - over ten different signals, resound far in sea:
water is much better transmitter of sounds than air. Some
of dolphins's sounds are ultrasonic ones - we can't hear them.
These very high frequency sounds are used for echolocation
- reflection of ultrasonic waves from underwater objects returns
to dolphin, telling animal of the distanca, size, form, direction
of movement and speed of the object. Thus they know of the
proximity of the bottom, learn about other members of their
family location, find out about fish schools that are still
out of visibility (which is particularly important in the
quite turbid
Black Sea, especially in its nearshore waters). Trainers
at dolphin shows use ultrasonic whistles to give a command
to dolphins to perform a trick. Still communication signals
used by dolphins - sounds and movements - do not make up for
a real language: only words, no phrases.
Dolphins live in family packs - all members of the school
are relatives, this is thoght to be the reason for their mutual
assistance and developed co-operation. They always help their
wounded or just weakened kin to keep on the surface, don't
let it drown supporting its body from beneath, pushing it
upwards. There tales about similar cases of dolphins' help
to drowning people; it's being suggested that dolphins can
treat human as their kin. Legends of dolphins helping people
are abundant, some of them date back to ancient times; many
of them sound more like fairy tales; still there no proven
case of dolphin's hostility to man.
Bottlenose dolphin (Tursiops truncatus) is the most
common species of dolphin in the Black Sea nearshore waters;
this dolphin is common at the coasts of all continents, in
all oceans, except polar regions. Bottlenoses are also most
popular actors in dolphin shows, they endure captivity easier
than other dolphin species. They learn show tricks very fast:
dolphin trainers tell that it's usually enough just single
correct performance awarded by a fish, for the signal-trick-award
procedure became a habit. On the other hand, dolphins may
as easily forget the learned trick - if not awarded, even
once.

Big dolphin's heads contains big brain indeed, but it's not
for lot of thinking: it's just that big body requires many
neurons to govern it (blue whales or elephants have even bigger
brain). Still dolphin's brain have one very unique feature:
it never sleeps. Left and right hemispheres of dolphin's brain
sleep in turns, one after another, because dolphin need to
emerge on surface for breathing. At night this diving-surfacing
behavior is controlled by the two brain hemispheres working
in shifts.
People started to study and train dolphins in the middle
of twentieth century, for dolphins' shows and for military
purposes. The results of that work were so successful and
so widely advertised, that soon a legend of unusually high
dolphins' intellectual level formed. Sometimes one might hear
(mostly from movies) that dolphins are almost as clever as
human, only they have "another kind of mind". Modern
scientific knowledge of dolphins' brain and behaviour puts
these marine mammals' learning ability on the level of a dog;
a long way to anthropoid apes.
Still
something makes us treat dolphins in somewhat different way
than other human-friendly animals. Joyful, cute, nice, friendly
- all true about dolphins. And, yes - they sometimes helped
people in the sea. Kids (and adult people too!) love playing
with them in oceanariums, at dolphin shows: dolphins themselves
come and play with people. Also, dolphins always smile! Of
course, one might say that it's just structure of their sculls
and facial muscles... Still - they smile, and their smile
looks more genuine and sincere than smiles of many people;
this big smile on a big face with big cheerful eyes - it makes
everyone smile too. Usually, after swimming with dolphins,
people keep on smiling (with no other special reason) half
an hour - on the average. A course of dolphin therapy helped
many kids suffering nervous disorders.
Skin of dolphins is a miraculous tissue, it's capable of
extinguishing turbulent vortexes, that usually slow down any
swimming body - this another secret of dolphins' very fast
swimming; submarine designers took dolphin's skin as a model
for building covers for their sisnister machines. The appearence
of dolphin's skin is deceiving: it looks like hard shiny plastik,
but when you stroke a dolphin passing by you, the feeling
is like you touch a fine silk.
Dolphin's trainers and scientists can tell some very non-miraculous,
even cruel stories of their favorite animals' life: of a severe
rules of hierarchy in dolphins' family-pack, of hard and tough
supression of a week individual; dolphins are animals. Still
all trainers, knowing all that, love their trainees, we all
love them; and after all attempts to explain what we love
them for - smiles, beauty of slender streaming bodies, their
games, playing with us, escorting our boats etc. - still something
inexplicable remains - dolphins are the best in their very
special way.
Occasionally we hear that dolphins (or whales) get washed
ashore, sometimes they purposefully swim to the shore and
waves throw them on the beach. This can happen when marine
mammals get sick, e.g. injured, or poisoned (for example,
after eating fish that have accumulated toxic planktonic algae
during red tides). Scientists discovered another one mechanism
of the dolphins' unusual urge to land. Sometimes , a combination
of the shore curve, the type of bottom sediments, and wave
power - all at one place - can generate a roar of the surf,
that, among all cacophony of different sounds, contains a
sound that is very similar to dolphin's (or whale's) signal
meaning "help me!". Obeying to instinct dolphins
rush to save their kin - and find themselves on the land.
Dolphin that just was thrown on beach should not be immediately
brought back into the sea: most probably the shocked animal
soon be back out of the water; experts' advice is to keep
landed dolphins in a pool filled with seawater (e.g. deep
trench dug in beach sand), until the animal recover itself.
Such cases with landed bottlenosed dolphins took place at
our beach, and keeping dolphin in a pool for 1-2 days worked
well.

Dolphins living in the Black
Sea
Another cosmopolitan dolphin species, common dolphin Delphinus
delphis can be rarely encountered at close proximity to the
shores in Black Sea. This species, distinguished by whitish
sides of the body, is more abundant off shore.
People living on Black Sea shores were always hunting dolphins:
dolphin skin made a fabric for fishermen waterproof clothes,
blubber being burned in lamps gave people light, and dolphin
meat was just a kind of food. To the mid-twentieth century
all species of dolphins in the Black Sea became endangered
species. Most Black Sea countries banned hunting dolphins
in 1960s, Turkey joined the ban in 1980s. Since then, populations
of all three species of dolphins in the Вlack Sea are growing
- very visibly. For example, porpoise - smallest and most
suffered from hunting species of dolphins in the Black Sea
(its blubber was rated most high) - was very rare at all coasts
in 1990s; now porpoises can be seen at Caucasian coast, and
in some areas near Crimean shore they became really common
species of dolphin, sometimes outnumbering bottlenosed dolphins
(e.g. entrance to Balaklava Bay). Still thousands of dolphins
in the Black Sea continue dieing of unnatural causes each
year; most usually they got entangled in fishermen nets, and
suffocate not being able reaching seasurface. Some fishermen
regard dolphins as competitors, and finding them still alive
in their nets, finish them off. Nevertheless, growing numbers
of dolphins showing us their wet black backs in the waves,
is a very obvious, spectacular, and inspiring example of success
in saving rare species of marine animals - a small piece of
a whole marine life - by the desisive and concerted action
of Black Sea people, nations, governments.

Common porpoise (Phocaena
phocaena), or azovka, can be identified by a low, shortish
dorsal fin, and short, fast breathing rolls over the sea surface
- as compared to bottlenose and common dolphins

Bottlenosed dolphins
(Tursiops truncatus)
Dolphins eat fish, a lot of it - each animal
needs 10-30 kg fish a day. They are homoiothermal (warm-blooded)
animals, and have to keep body temperature at over 30oC in
sometimes very cold water (often around 0oC during Black Sea
winters; average man survive several minutes at those condititions);
also they swim fast all their life. Both maintainance of high
body temperature in cold environment and swimming are extremely
energy-consuming jobs. Subcutaneous blubber helps keeping
dolphin warm serving both as a thermo-insulation, and as an
intracellular stock of energy; adipose tissue is an active
heater - burning fat is warming up dolphin's blood. Fuel stock
needs to be replenished, and this why dolphins are always
hunting, resting only during night sleep. They find fish scholls
using ultrasonic echolocation and shortly overtake and surround
them - there are no living creatures in the Black Sea swimming
faster than dolphins. When the hunt takes place very close
to shore, dolphins assume half-circle formation, and tightening
the cordon push disconcerted fish flock almost to the beach,
eating fish in surf waves. Sometimes it happens at depths
less then one meter: dolphins' backs shine above water, their
pectoral fins scraping the bottom.

Having overrun fish shoal in the sea, dolphins don't rush
on the prey at random, each on its own; they encircle and
concentrate fish (whistling, pounding of tailfins on waves,
jumping out of water and bumping on seasurface help them doing
it), and then feed - in order of pack hierarachy, one after
another - starting from alpha male and his female. Having
got food, a dolphin returns to its place in the cordon.
Dolphins always are where there are fish. For example, at
Caucasian coast of Black Sea fish is most abundant in spring
and autumn. In spring shoals of khamsi (Black Sea anchovy
Engraulis encrasicholus ponticus) and mullet (Mugil cephalus
and Lisa aurata) migrate along shore northward: from overwintering
areas (deep places off Caucasian and Anatolian coasts) to
the Sea of Azov, which is rich of their food (for khamsi it's
plankton, for mullet - it's detritus). Huge schools of pilengas
(large Far-Eastern species of mullet Mugil soiuy introduced
into Black Sea) aligned in long trains move in opposite direction
- from North to South along the shore; groups of bottlenosed
dolphins, ranging from several to dozens of animals patrol
near-shore waters intercepting migrating fish - sometimes
making a spectacular show for those watching from the beach.
In autumn fish schools travel back to overwintering areas,
again - with dolphins chasing them. Hundreds of dolphins make
a cordon in the gates of the Sea of Azov - Kerch Strait, meeting
there all migrating fish.
In summer dolphins also are not rare near our shores, since
mullets, horse mackerel, atherina are there. They can be met
even near the most crowded beaches, but - mostly during the
hours when there are less people there.
Learn about dolphins and
whales, look for them - in the sea.

The following pages are available
only in Russian:
Black Sea
Marine Life - sandy bottom habitats - fishes, crabs,
mollusks...
Black
Sea Marine Life - sandy bottom habitats - let's think about it
Black Sea
Marine Life - submarine rocks - near
the surfline
Black
Sea Marine Life - submarine rocks -
deeper
Black
Sea Marine Life - submarine rocks -
even deeper
Oil pollution, coastal deforestation, etc.
Aegean Sea - compare to Black Sea
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