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SOME POISONOUS MARINE ANIMALS
A Review From Sharky's Dive
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VENOMOUS FISH
Well over 200 species of marine fish, including the Stingrays,
Scorpionfish, Zebrafish, Stonefish, Weevers, Toadfish, Stargazers, and certain of the
Shark, Ratfish, Catfish and Surgeonfish are known or thought to be venomous. The great
majority of venomous piscines are nonmigratory and slow swimming. They tend to live in a
protected habitat in or around rocks, coral, kelp beds, or they spend much of their time
buried in the sand.
A. STINGRAYS: (Elasmobranchs)
REGION:
Inhabit most of the world; species include diamond, butterfly, European, eagle,
California and South American freshwater stingrays; all large freshwater varieties are
dangerous. The venom is known to exert a deleterious effect on the mammalian
cardiovascular system. Low concentrations of the venom give rise to simple peripheral
vasodilatation or vasoconstriction. The venom depresses respiration. The stinger is a
bilaterally serrated, dentinal caudal spine located in the upper part of tail. Usually the
are very camonflaged lying on the bottom and partially covered by sand. The main danger is
stepping on one. When stepped on the ray strikes upward and drives the spine deeply into
foot or leg. As the stinger enters the flesh, the integumentary sheath surrounding the
spine is ruptured and the venom escapes into the victim's tissues. In the withdrawal of
the spine, the integumentary sheath may be torn free and remain in the wound. Unlike the
injuries inflicted by many venomous animals, wounds produced by the stingray may be large
and severely lacerated, requiring extensive debridement and surgical closure.
DIAGNOSIS:
Penetration of the skin by the barb in the tail of the stingray causesimmediate onset
of intense pain, out of proportion to that which might be produced by a similar
nonvenomous injury. While the onset of pain is usually limited to the area of injury, it
rapidly spreads, and usually becomes more severe during the first 30 min following the
accident. In most cases the pain reaches its greatest intensity in less than 90 min and
often persists (if untreated), though gradually diminishing in severity, for 6-48 hr.
symptoms and signs of the poisoning are localized to the injured area. However, syncope,
weakness, nausea and anxiety are common complaints and may be attributed, in pary,
toperipheral vasodilatation and in part to the reflex phenomenon precipitated by the
muscles of the affected extremity, generalized cramps, inguinal or axillary pain, and
respirtory distress are less frequently reported. Arrhythmias, paresthesia, and
convulsions may occur. Swelling, Nausea, Vomiting, Abdominal pain, Dizziness, Weakness,
Generalized cramps, Sweating, fall of BP; Fatalities have occurred when the barb has
penetrated the chest or abdomen
TREATMENT:
A treatment to be successful must be instituted early and vigorously, and should be
initiated by the victim It must be directed towards alleviating the pain, preventing
complications that may be evoked by the venom, and preventing secondary infections.
Injuries to an extremity should be irrigated with the salt water at hand, since much of
the venom can be washed from the wound by this step. An attempt should be made to remove
integumentary sheath if it can be seen in the wound. The extremity should then be
submerged in hot water at as high a temperature as the patient can tolerate without injury
for 30-90 min. The addition of sodium chloride or magnesium sulfate to the hot water is
optional. The wound should then be further examined for evidence of the integumentary
sheath, debrided, sutured if necessary, The approprite antitetanus agent administered.
- A) Wash wound with sterile saline solution or cold water.
- B) Try to remove remaining portion of stinger sheath.
- C) Soak in plain water as hot as possible for at least 30 to 60 minutes. Use hot presses
on areas not immersed.
- D) When pain subsides, elevate limb.
- E) Call Doctor. If abdomen or chest wound,rush to hospital.
- F) Tetanus prophylaxis and antibiotics
B) Lionfish (P volitans)
REGION: Shoals of the beaches in Barbados.
DIAGNOSIS: Site of bite is inflamed, edematous and very painful; systemic symptoms may
consist of tachycardia, dyspnea, profuse, erspiration, vomiting diarrhea, and intense
colicky abdominal pain.
C. Catfish
D. Weeverfish The weever,members of the piscine family Trachinidae, are
small marine fish which are confined to the eastern Atlantic and Maditerranean coasts. The
venom apparatus of these fish consist of two opercular spines, five to eight dorsal
spines, and the tissues contained within the integumentary sheaths surrounding the spines.
SYMPTOMS:
A weeverfish may inflict either a single or multiple ncture-type wound. Persons stung
by these fish report having received a sharp, immediately painful stab. The pain is
described as intense or excruciating: it increases in severity during the first 20 to 50
min following the injury and may persist for 16 to 24hours if treatment is not underraken.
In severe cases of envenomation by weevers there may be weakness, dizziness, nausea,
primary shock and respiratory distress. In severe stings there was considerable axillary
and chest pain as well as changes in pulse rate and respiration.
TREATMENT: Treatment of stingray injuries are equally effective an allevialing the
severe pain and other symptoms provoked by the venom of the weeverfish.
E. Rayfish Scorpionfish (Scorpaena guttata)
At least 80 members of the family Scorpionfish or rockfish, have been implicated in
poisoning to man, or have been studied by venomologists. Included in this group are the
Zebrafish, Sculpins, Stonefish, Bullrout and Waspfish.
REGION: Temperate and tropic zones of all seas.
E. ZEBRAFISH (Pterois)
The Zebrafish, Lionfish, Turkeyfish or Butterfly cods are spectaculary colored
scorpionfish, usually found in shallow waters around coral heads, in underwater caves and
about underwater debris.
VENOM APPARATUS:
It consists of 13 dorsal spines, 3 anal spines, 2 pelvic pines, integumentary sheaths,
and the glandular complex lying within the anterolateral grooves of the spines.
SYMPTOMS:
Envenomation gives rise to immediate intense, sometimes burning pain, which radiates
from the injured area more rapidly than in the case of weeverfish or stingray poisoning.
The pain often becomes unbearable within a few minutes following the injury, and may cause
the victin to thrash about in considerable agony. Weakness, dizziness and shock may
quickly ensue. In cases of shock there is often brady-cardia, hypothermia and respiratory
distress. Cyanosis has been reported. Edema develops rapidly. Necrosis and sloughing of
the tissues about the wound may occur. The pain often persists for 8 to 12 hours, and the
injured pary may be sore and swollen for several weeks. Stings by P.volitans and related
species provoke more severe. This fish is capable of producing a fatal poisoning in man.
If the pain dose not respond to hot water, meperidine hydrochloride may be given.
Cardiovascular tone can be maintained with intravenous fluids and epinephrine; it is
advisable to give oxygen.
2. SCORPAENA (Scorpaena) Its various members are known in different parts of the world
as scorpionfish, sculpins, rockfish, sea pigs, bullrouts, waspfish, bullheads or blobs.
Apistus, Centropogon, Gymnapistes, Hypodytess, otesthes, Scorpaena, Scorpaenodes,
Scorpaenopsis, Sebastapistes, Sebastodes, Sebastolobus, and Snyderina.
SYMPTOMS:
Envenomation on a finger is followed almost immediately by intense, sometimes pulsating
pain in the area of the injury. The pain radiates so that within 3 to 10 min. it may
involve the entire finger or hand. The area around the wound may appear ischemic; bleeding
dose not seem to be affected. The finger becomes red and swollen. The pain may extend up
the forearm and into the axilla within 15 min of the sting. Nausea, vomiting, weakness,
palor, syncopy, an urgency to urinate, conjunctivitis, inccreased perspiration, headache
and diarrhea have all been reported. In severe stingings excruciating pain, causing the
victims to thrash about in agony. Primary shock may occur, and in two cases the victims
were taken to the hospital under oxygen administration. Respirations may become labored
and painful. Pulmonary edema has been reported and "abnormal electrocandiograms"
demonstrated. In one case known to the auther the patient had a pulmonary embolism and was
hospitalized for 24 days.
TREATMENT:
The treatment for Scorpaena guttata envenomations has long been hot water and the
protocol as suggested under stingray injuries.
3. STONEFISH (Synanceja) These fish are perhaps the most dangerous of the
venomous piscines; centainly, the stonefish or dornorn, devilfish, goblinfish, sea toad,
lumpfish, lupo or stingfish. There are a number of species of Synanceja, and they vary in
color from brown or green to scarlet with gray markings. The adult of most species is 10
to 15 inches in lenght, they may reach 2 ft in lenght and may weigh over 3 lb., and
remarkably resemble stone or coral. They have the habit of lying motionless in the coral
or rock, or partially buried in the sand or mud, and so still can they lie that molluscs
and other benthonic marine animals may often crawl over them.
SYMPTOMS:
Deaths from stingings by these fish are not uncommon and may occur within several hours
of envenomation. Necrosis of tissues, is more common following stings by Synanceja than
following injuries by the other venomous fish. The clinical evidence to date indicates
that lethality, pain and necrosis are correlated in certain of the venomous piscines.
TREATMENT:
The use of hot water as described for stingray wounds should be tried. Injection of
emetine hydrochloride directly into the wound(s) is of value, if it can be accomplished
within 30 min of the stinging.
- G) Toadfish
- H) Surgeonfish
- I) Rabbitfish
PREVENTION: Unfamiliar area, Consult local divers as to marine life hazards.
SYMPTOMS:
Resembles those of stingray;severe local pain and swelling, with extension of pain and
swellingto involve the entire extremity. Although less sizable wounds but produce more
serious local and general reaction.
TREATMENT:
- A) Get him out of the water.
- B) Keep him lying down.
- C) Treat for shock.
- D) Proceed with measures used for stingray injure.
- E) Infiltrate wound with 2% procaine if pain is severe.
- J) SEA SNAKES: Length to 9 Ft.
Unprovoked attacks are very rare. The venom of all species of sea snakes is extremely
toxic, and is said tobe fifty times more powerful than that of the king cobra. The
mortalityrate is estimated at about 25 per cent. They are true snakes, with
lidlessimmivable eyes, and a typical forked tongue. Most species are three to four feet.
REGION:They are found chiefly in the tropical Pacific and Indian Oceans. Sea-snake
venom is primarily myotoxic and myoglobinuria becomes evident early. The onset of symptoms
after a bite is usually one hour and they are egeneralized. They consist initially of
thickening of the tongue and overall stiffness of muscles, which gradually develops. There
may be pain upon movement, and ascending, general paralysis soon follows.
SYMPTOMS:
- A) General unwell feeling or some sense of well being
- B) Sensation of thickening of tongue.
- C) Feeling of muscular stiffness.
- D) Aching pain on movement.LATER:
- E) Spreading weakness.
- F) Drooping of eyelids.
- G) Tightening of jaw muscles.
- H) Difficulty in speaking.
- I ) Thirst,dryness of throat.
- J) Shock symptoms
- K) Muscular spasm
- L) Respiratory difficulties
- M) Convulations
- N) Unconsciousness
TREATMENT:
Is little different from that employed after the bites of land snakes. A tourniquet is
applied to the thigh in leg bites and to upper arm in bites of the hand or wrist. It must
be loosened every half hour. The patient should be carried to a hospital immediately. The
snake should be captured if possible and identified because it may turn out to be a
harmless water snake. Receive immediate administration of antivenin, polyvalent antiserum
containing a krait fraction. Twenty milliliters should be injected slowlt by vein, After
doing sensitivity tests. Cortisone has been given to prevent possible severe anaphylaxis.
If cortisone fails to control the serum therapy reaction, epinephrins may be required.
Tetanus toxoid or antitoxin. Adequate maintenance of fluid and electrolyte balance is
imperative. Antibiotics should be used in case of infection.
- A) Keep affected part quite, avoid exertion
- B) If bitten in arm or lag apply tourniquet above the wound.
- C) If possible capture and kill the snake and it identified.
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