BY: SHAIZA SAEED MALIK

IN FISH CULTURE FISH HAVE MANY ENEMIES. THEY ARE FOUND AMONG INSECTS, FISH, AMPHIBIANS, REPTILES, BIRDS AND MAMMALS. THEY CAN BE DIVIDED BETWEEN PERMANENT

ENEMIES (OF EGGS, FRY AND ADULTS), OCASIONAL ENEMIES AND THOSE COMPETING FOR FOOD

•HARMFUL INSECTS

•VORACIOUS FISH

•HARMFUL AMPHIBIANS

•HARMFUL REPTILES

•HARMFUL BIRDS

•HARMFUL MAMMALS

HARMFUL INSECTS1)WATER BEETLES

1)GREAT DIVING WATER BEETLE

•30 - 35 mm (ADULTS)•EAT FRY •VERY VORACIOUS•LARVAE DO NO HAVE MOUTH•LARVAE HAVE TWO POWERFUL HOLLOW MANDIBLES•LARVAE SUCK VICTIMS LEAVING ONLY SKIN•CAN DO LOT OF HARM TO NURSING PONDS

2) BLACK WATER BEETLE

•ADULTS 40-50mm

•ADULTS- NOT HARMFUL

•ADULTS- VEGETARIAN

•LARVAE 60-80 mm

•VERY STRONG PREDATORS

•CAN DESTROY A LOT OF FRY

Larva of Black Water Beetle

2)WATER BUGS

• VERY NUMEROUS

•VARYING DEGREE OF ENMITY

•UNDESIRABLE COMPETITORS FOR FOOD

•ONLY SMALL SPECIES SERVE AS FOOD FOR FISH

•MOST HARMFUL ARE:

1. Naucoris cimicoides -15 mm2. Notonecta glauca- 15 mm3. Nepa cinerea

Naucoris cimicoidesVentral view (left), Dorsal View (Right)

Notonecta glaucaExcellent back swimmer (left)

Nepa cinereaStrong Predator with a Pointed Strong Nose

WATER SCORPION Nepa cinerea

3)DRAGONFLIES

• NYMPHS ARE AQUATIC•THE ADULTS FLY•NYMPHS ARE RECOGNISED BY EXTENDING LOWER JAW FOLDED LIKE A HINGE•NYMPHS OF Agrionidae:

Have Long and Slender BodiesAre Harmless

• NYMPHS OF Aeschinidae:Long and Robust BodiesMore Dangerous

•NYMPHS OF Lebullilidae:

Short Stout BodiesMore dangerous

DRAGONFLIES (NYMPHS)

Aeschinidae nymph:

Libellulidae nymph:

VORACIOUS FISH

1. Consuming or eager to consume great amounts of food; ravenous.2. Having or marked by an insatiable appetite for an activity or pursuit; greedy.

DEFINITIONS:

FOLLOWING ARE SOME VORACIOUS FISH:

PIKE

PIKE-PERCH

PERCH

PIKE

UP LEFT: SHOWING HORRIBLE TEETH OF PIKE.

BOTTOM RIGHT:TIGER PIKE

PERCH

PIKE-PERCH

UP LEFT: SHOWING A PIKE-PERCH

BOTTOM RIGHT: PIKE-PERCH CHASING A LIVE FISH TO EAT

LESS VORACIOUS FISH

LESS VORACIOUS ARE THOSE WHICH:

• IN PARTICULAR ARE COMPETITORS OF FOOD

•GET INTO UNPROTECTED PONDS

•INCLUDE:

Black bullhead (Ictalurus melas) in Europe

Hemichromis spcs in Africa

•GET INTO BADLY INSTALLED WATER INLETS

•OR IF PONDS ARE NOT MAINTAINED; INTERVALS

BETWEEN DRYING ARE TOO LONG AND IRREGULAR

LESS VORACIOUS FISH

BLACK BULL HEAD

HEMICHROMIS spcs

HARMFUL AMPHIBIANS

•AS ADULT AND LARVAE, AMPHIBIANS ARE HARMFUL TO POND

CULTURE

•THEY COMPETE FISH FOR FOOD.

•BUT SOME SMALL TADPOLES SERVE AS FOOD FOR FISH

•THE MOST HARMFUL AMPHIBIAN ARE FROGS

•SOME LIVE OFF FRY.

•TADPOLES SPECIALLY MAKE GRADING OF TILAPIA FRY DIFFICULT

•TADPOLES OF GENUS XENOPUS ARE SEEN TO DISGORGE PARTIALLY

DIGESTEDSMALL TILAPIA FINGERLINGS.

FROGSXENOPUS EATING A FISH

HARMFUL REPTILES

Reptiles which can swim easily and live for most part in water can destroy many fry and even good size fish. The destruction they cause is higher in open waters than in ponds.

HARMFUL BIRDSA NUMBER OF ICTHYOPHAGOUS WATER FOWLS

•KINGFISHERS

•GREY HERONS

•DUCKS &

•Many other WATER BIRDS

ARE HARMFUL TO THE FISH PONDS.

• WATER HENS AND SWANS however are vegetarian and do not destroy the

fry.

BIRDS CAN NOT READ!

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KINGFISHERAleedo athis L.

•BEAUTIFUL BLUE-GREEN BIRD WITH IRRIDESCENT GLINTS

•MEASURES FROM 16-17 cm IN LENGTH, HAS STRONG AND POINTED BEAK

•FAST FLYER AND SKIMS OVER WATER

•PERCHES ON POSTS, BRANCHES OR TREE TRUNKS

•PLUNGES LIKE LIGHTNING ON ITS PREY

•PREY ARE SMALL FISH FROM 4-7 cm.

•IT CAN SWALLOW FROM 10-12 A DAY

•IT NESTS IN BURROWS MADE BY RATS IN BANKS.

HERE YOU ARE MY FISHY!!!

I CAUGHT YOU KID!! HAHA…

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GREY HERONArdea cinerea L.

•LARGE BIRD WITH LONG LEGS, NECK AND BEAK

•CAN MEASURE UP TO 1 m. WING-SPREAD IS 0.70 m

•LIVE ROUND SHALLOW WATERS

•SHOWS PERFECT CAPTURING TACTICS

•FISH(verb) DURING DAY OR WHEN NIGHTS ARE CLEAR.

•CAN SWALLOW WHOLE FISH BETWEEN 15 AND 20 CM

•DESTROY GREAT QUANTITIES OF FISH

DUCKS

DUCKS•DUCKS DISTURB THE FISH BY THEIR UNCEASING COMING AND GOING

•THEY DESTROY THE SPAWN AND FRY ON SPAWNING BEDS & IN FRY PONDS

•THEY CAN BE USEFUL IN GROWING PONDS TOO….

•THEIR EXCREMENT ACTS AS FERTILIZER

SWANS

SWANS

•LIVE OFF WATER VEGETATION

•ARE NOT HARMFUL EVEN IN NURSERY PONDS

•EXCREMENT FERTILIZES THE PONDS BUT DIRTIES THE BANKS

WATER HENS

WATER HENS

•ONCE THOUGHT TO BE FISH EATER ARE THE CUTE WATER HENS

•THEY ARE VEGETARIAN

•DO NOT DESTROY THE FRY OR FISH.

HARMFUL MAMMALS

OTTERS

Lutra lutra L.

•ARE LARGE MUSTELIDAE.

•CAN MEASURE OVER 1 m OF WHICH 40 cm IS TAIL LENGTH.

•CAN WEIGH 10kg

•PRINCIPALLY LIVE OFF FISH

•SUPPLEMENT THEIR FOOD WITH AQUATIC ANIMALS

•IF FOOD IS ABUNDANT THEY DESTROY MORE THAN THEY CAN EAT

•THAT IS WHY THEY ARE MORE HARMFUL FOR WINTERING PONDS

•NOT HARMFUL FOR NURSING PONDS

•THEY ARE VERY TRICKY; SWIM AND PLUNGE WITH EASE

•BUT CAN EASILY BE TRACED THANKS TO THEIR WEBBED FOOT-PRINTS

MUSK-RATOndatra zibethica L.

•IMPORTED FROM AMERICA IN 1905 FOR FUR

•LIVE IN STAGNANT AND SLOW RUNNING WATER RICH IN AQUATIC

VEGETATION

•RARELY ATTACK FISH IN WINTERING PONDS

•HARMFUL BECAUSE OF LARGE BURROWS THEY DIG IN BANKS AND DIKES

WATER SHREWNeomys fodiens

•LITTLE RODENT

•MEASURES FROM 10-13 cm IN LENGTH UP TO TAIL

•HAS LONG MOBILE SNOUT AND SWIMS PERFECTLY

IT DESTROYS EGGS AND FRY

IT SPECIALLY GOES FOR TROUT EGGS

TROUT EGGS

INCECTSWATER BEETLES, WATER BUGS & DRAGONFLIES

1. DO NOT PLACE NURSING PONDS UNDER WATER MORE THAN 15

DAYS BEFORE STOCKING IN ORDER THAT HARMFUL LARVAE OF

INSECTS HAVE NO TIME TO DEVELOP

2. CLEAN UP SWAMPS AND GRASSY DITCHES IN THE

NEIGHBOURHOOD OF THE FISH FARM

VORACIOUS FISHPIKE, PIKE-PERCH & PERCH

1. DO NOT LET IN THE VORACIOUS FISH IN NURSING PONDS BY

CAREFULL MANIPULATION.

2. INSTALL POND (SUNK HORIZONTAL SCREEN AT THE WATER INLET

AND POSSIBILITY OF COMPLETE DRYING OUT).

3. PUDDLES OF WATER DRYING CAN BE TREATED WITH QUICKLIME.

LESS VORACIOUS FISHBLACK BULLHEAD &HEMICHROMIS spcs

1. THEY GET INTO UNPROPERLY INSTALLED WATER INLETS.

2. INTERVALS BETWEEN DRYING SHOULD NOT BE TOO LONG.

3. INTERVALS SHOULD BE REGULAR.

AMPHIBIANSMOSTLY FROGS AND

TADPOLES

1. CARP NURSING PONDS SHOULD BE HANDLED CAREFULLY WHEN GRADING

2. BAITED TRAPS FOR XENOPUS SHOULD BE USED

3. DESTROY THE EGGS OF AMPHIBIANS AS SEEN

4. YOU CAN USE SCOOP NET FOR THIS PURPOSE.

5. USE OF QUICKLIME IS ALSO GOOD TO DESTROY EGGS

6. ADULTS CAN BE CAUGHT UP IN WIRE TRAP NETS

BAITED NET INSTALLATION

REPTILESMAINLY SNAKES AND

CROCODILES

1. PONDS MUST BE INSTALLED IN AREAS NATURALLY AWAY FROM

SNAKE AND CROCODILE HABITATS.

2. THE POND SITE MUST BE SIGHTABLE FROM ALL SIDES.

3. BUSHES, SHRUBS AND WEEDS MUST BE PROPERLY CLEANED

EVERYDAY

4. REPELLANTS CAN BE USED SO THAT REPTILES MAY NOT TRY TO

ACCESS

5. PONDS SHOULD NOT BE NEAR NATURAL OPEN WATER SITES

BIRDSKINGFISHERS, GREY HERONS,& DUCKS

1. IF DESTRUCTION OF

KINGFISHER IS

AUTHORIZED BY LAW, IT

CAN BE SHOT .

2. SPRING TRAPS CAN BE

PLACED ON POSTS ON

ELEVATED HEIGHT (1m).

3. THESE POSTS SHOULD BE

FAIRLY ISOLATED

OTHERWISE BIRDS WILL

PREFER THE NEAR-BY

TREE BRANCHES.

GREY HERONS:

1. THE BEST WAY IS TO SHOOT THEM (WHEN LEGALLY PERMITTED)2. THEY CAN BE TRAPPED WITH OR WITHOUT USE OF BAIT.3. THEY CAN BE POISONED BY INJECTING A DEAD FISH WITH STRYCHNINE

OR PHOSPHORUS.4. THEIR NESTS CAN BE DESTROYED OR YOUNG ONES CAN BE TAKEN

AWAY (CAN BE TAKEN IN CAPTIVITY OR BE SALED OUT).

DUCKS:

1. DUCKS USUALLY DO NOT ACCESS THE MAN MADE PONDS EXCEPT THAT DUCKS ARE NATURAL INHABITANTS OF THAT PLACE.

2. IF DUCK ARRIVES IT SHOULD BE TRAPPED BY CASTING NETS.3. ITS YOUNG ONES ALSO BE TRANSPORTED TO SOME OTHER PLACE.

MAMMALSOTTERS, MUSK-RATS & WATER SHREWS

1. THE BEST WAY TO COMBAT OTTERS IS TO USE TRAPS:2. SOLID TOOTHED TRAPS SHOULD BE USED3. PLACE THESE TRAPS UNDER WATER OR AT ENTERNCE OR EXIT SITE

OF WATER.4. TRAP SHOULD NOT BE BAITED.5. SHOULD BE HELD BY AT LEAST A 3 METER LONG CHAIN.6. SUITABLE FENCING OF WINTERING PONDS IS A MUST.

MUSK-RATS :1. WINTERING PONDS MUST BE TAKEN CARE OF BY THESE RATS.2. THEY CAN BE TRAPPED OR POISONED.

WATER SHREWS:

1. CAN BE DESTROYED BY POISON OR TRAPS.2. FUMIGATE ITS BURROWS WITH SULPHUR.

OTTER TRAP

MADE BY: SHAIZA SAEED MALIK

M.PHIL 1ST SEMESTER

2014-2016

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TEXTBOOK OF FISH CULTUREMARCEL HUET.

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