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The Black Sea is a friendly sea, for there are very few
hazardous marine animals- even for children. A few species
that can be annoying are listed below.
Rhizostome jellyfish
Rhizostoma pulmo can
sting your skin with its thread-cells located on the lacy
peristomal tentacles. It is better to avoid it when swimming;
Though nettle stings stronger than this jellyfish.
Moon jellyfish Aurelia
aurita is another
Scyphozoan medusa common in the Black Sea. Its thread-cells
located on the canopy fringe tentacles are less potent weapon
than those of Rhizostoma; they cannot penetrate even
children's skin. Contact of this
jellyfish with eyes still should
be avoided.
Jellyfish immobilize or even kill their prey (small planktonic
animals mostly) with the use of thread-cells containing venom
capsule with a sharp, saw-edged coiled harpoon attached to
it.
The spring uncoils and hit the prey when it
touches sensitive hair on the thread-cell surface. Spike of
the hollow dart breaks inside the victim body, and paralyzing
venom pours out. Thread-cell is a disposable weapon.
Coelenterate thread cell
action
Interesting is that newly hatched silvery horse-mackerels
often crowd between Rhizostoma tentacles, and travel
with jellyfish. Thread-cells do not harm these tiny fishes
- just like tentacles of tropical actiniae don't act on clown-fish
living between them.
Black Sea scorpion-fish Scorpaena porcus. It
is a monster: a big head covered with skin flaps, protruding
red eyes, huge mouth with thick lips. Dorsal fin's rays of
scorpaena became poisoned spikes - venom glands locate at
the base of each ray. Another couple of hard poisoned prickles
grow from gill flaps. These thorns are scorpaena's defense
weapon, whereas its weapon of attack is a great many sharp
crooked teeth. Scorpion-fish is a predator hiding between
rocks and algae, indistinguishable from them due to the camouflage
of color spots and skin shreds. Scorpaena waits until smaller
fish approach within attacking distance - a violent rush follows
and the prey being swallowed within a split second.
Black Sea scorpionfish
Scorpaena porcus
Everything in scorpaena's ugly appearance tells
about the menace; at the same time - it's nice. There are
grey, charcoal-black, pink, brown, purple-yellow scorpaenas
- depending on the dominant habitat colors. It dwells mostly
among underwater rocks, but also can occur on the sandy bottom;
it is a usual, abundant fish reaching 50cm length. Scorpion-fish
represent threat mostly for fishers - when they handle the
catch. No cases of accidental pricks by scorpaena are known;
just do not touch it.
Noticeable
scorpion-fish Scorpaena notata
Another local species of scorpion-fish is noticeable
scorpionfish Scorpaena notata, it does not exceed
15cm, and has smaller supraorbital skin flaps than those of
Scorpaena porcus. Wounds inflicted by Scorpaena's
venomous spikes severely hurt and swell, then general allergic
reaction follows: weakness, raised body temperature, headache.
No lethal cases after Scorpaena wounds were registered. Helpful
is antihistamine medication under doctor's supervision.
| More dangerous member of Scorpaenidae
family occurring in Black Sea is weever
Trachinus draco. It is a fish with elongated
body and angular head. Like many other benthic predator
fishes weever have big protruding eyes in the upper part
of head, and a very big mouth. This fish (anglers
sometimes call it snake) prefer soft bottom habitats -
sand or silt. It digs into the bottom leaving only its
eyes on the surface, and watches the prey - smaller
fishes. When disturbed, weever spreads noticeable black
dorsal fin, all five rays of which are venomous spikes.
Like scorpion-fish it possess directed backward venomous
spike on each of the gill flaps as well. There were
cases of accidental stomping on weever's rays on sandy
shallows in Mediterranean Sea; so far, no such cases are
known at Black Sea coasts. The consequences of the
weever pricks are much heavier (lethal outcome possible)
than in the case of scorpaena. Injured person must be
taken to hospital in any case. |
Weever Trachinus draco,
Black Sea
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Skates are flat benthic sharks; they
have no sides - only back and belly - dorsal and ventral surfaces.
They swim waving with their "wings" - flattened body sides,
whereas their tailfin is reduced to tail-stem. They live on
the sandy or silt bottom, and find their food on the bottom:
shellfish and small fish. Two species of skates live in the
Black Sea: larger (its length up to 1.5m, with tail) thornback
skate Raja clavata, and smaller (< 0.7m) common
stingray Dasyatis pastinaca.
Common stingray Dasyatis
pastinaca, Black
Sea |
Like in all
sharks, their skeleton is composed of cartilage.
However, stingray has one long - up to 20cm -
bone: tale prickle. It is a saw-edged, very sharp,
pointed blade. Being disturbed, stingray uses its tale
as a weep against invader, sticking out the prickle at
the same time. Resulting wound may be deep and severe
one. Fortunately, these rays are very scary, and rush
away from swimmers and divers. |
Black Sea spiny shark, piked dogfish Squalus
acanthias, Russian name katran, like all fish species
listed above may represent threat only to fishermen when they
handle the catch: two venomous spikes in front of dorsal fins
being raised as a response to disturbance. Dogfish prefer
colder water, and during the warm period of year, it stays
beneath summer thermocline - deeper than 20m.
Black Sea fish species lists accounting for
all species ever reported in the Sea include small-spotted
catshark Scyliorhinus canicula, and even hammerhead
shark Sphyrna zygaena; these list entries correspond
to a few occasional intrusions in past hundred years. These
sharks are unable to settle in Black Sea because of its low
salinity and low water temperature in winter.
No more dangerous marine creatures in the Black
Sea. Kids often ask: Do crabs bite? They don't bite - they
pinch - and only when we grab them!
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