Flatfishes are the common name of the order Pleuronectiformes. The characteristic features of flatfishes are their asymmetry, mainly their eyes, both eyes on the same side of the head in juveniles and adults.
this presentation deals with the Flat fishes and their fisheries in India.
Exotic fish introduction to india and their impact on indigenous speciesAshish sahu
The exotic varieties of fish have been found to encroach the natural water bodies and adversely affect the indigenous fish species. ... Owing to extensive practice of composite culture, three fast growing exotic fishes are introduced along with the three Indian major carps.
What is biodiversity?
Father of biodiversity- E.O. Wilson.
The term ‘biodiversity’’ encompasses the variety of all life forms on earth.
Define biodiversity –
‘’ Biodiversity include of the particular area may be living organisms (plant and animal) called biodiversity ’’.
• Simple words in can be defined as the biodiversity .
“Variety, variability b/w genes, spp. and ecosystem”.
Define fish diversity –
“Fish Species diversity is defined as the number of species and abundance of each species that live in a particular location”.
The number of species that live in a particular location is called species richness.
India is one of the 17 mega biodiversity countries having four biodiversity hotspots namely the Western Ghats, eastern Himalayas, Indo-Burma and Sundaland that are included amongst the top ten most important hotspots in the world.
It also has rich freshwater(rivers, irrigationcanals,tanks, lakes,reservoirs) fish diversity.
Which living organisms–
All living organism in world 7.4 billion.
Fish Biodiversity in world-
World harbour total of 33059 spp. 4258 genera, 482 families about 58 % Marine water, 41% Fresh water and 1% migrants.
2-Fisheries resource of India –
India blessed with huge aquatic resources with 29,000 km of rivers, 0.3 million ha of estuaries, 0.9 million ha of back waters and lagoons, 3.15 million ha of reservoirs, 0.2 million ha of floodplain wetlands, 0.72 million ha of upland lakes and 2.02 million km sq area of Exclusive Economic Zone (EEZ) surrounding the seas,8129 km of coast line, which includes those of Andaman and Nicobar and Lakshadweep Islands.
The seas surrounding the country, 14 major rivers, 44 medium rivers and innumerable small rivers and other inland water bodies provide one of the richest faunastic resources of the world.
Exotic fish introduction to india and their impact on indigenous speciesAshish sahu
The exotic varieties of fish have been found to encroach the natural water bodies and adversely affect the indigenous fish species. ... Owing to extensive practice of composite culture, three fast growing exotic fishes are introduced along with the three Indian major carps.
What is biodiversity?
Father of biodiversity- E.O. Wilson.
The term ‘biodiversity’’ encompasses the variety of all life forms on earth.
Define biodiversity –
‘’ Biodiversity include of the particular area may be living organisms (plant and animal) called biodiversity ’’.
• Simple words in can be defined as the biodiversity .
“Variety, variability b/w genes, spp. and ecosystem”.
Define fish diversity –
“Fish Species diversity is defined as the number of species and abundance of each species that live in a particular location”.
The number of species that live in a particular location is called species richness.
India is one of the 17 mega biodiversity countries having four biodiversity hotspots namely the Western Ghats, eastern Himalayas, Indo-Burma and Sundaland that are included amongst the top ten most important hotspots in the world.
It also has rich freshwater(rivers, irrigationcanals,tanks, lakes,reservoirs) fish diversity.
Which living organisms–
All living organism in world 7.4 billion.
Fish Biodiversity in world-
World harbour total of 33059 spp. 4258 genera, 482 families about 58 % Marine water, 41% Fresh water and 1% migrants.
2-Fisheries resource of India –
India blessed with huge aquatic resources with 29,000 km of rivers, 0.3 million ha of estuaries, 0.9 million ha of back waters and lagoons, 3.15 million ha of reservoirs, 0.2 million ha of floodplain wetlands, 0.72 million ha of upland lakes and 2.02 million km sq area of Exclusive Economic Zone (EEZ) surrounding the seas,8129 km of coast line, which includes those of Andaman and Nicobar and Lakshadweep Islands.
The seas surrounding the country, 14 major rivers, 44 medium rivers and innumerable small rivers and other inland water bodies provide one of the richest faunastic resources of the world.
it is about the length and weight relationship of fish , growth, length, weight, absolute growth, isometric growth, relative growth, allometric growth,
1. Introduction
2.Principal Game fishes
(a)Fresh water game fishes
(b) Estuarine and sea game fishes
3.Sport Fishing and Tourism
*Mahseer (Barbus Tor) fishing
*Trout fishing
*Sea fishing
THANK YOU!!
Generalized and specific definition of pond and the types relating their size, use, construction method were illustrated. Besides the culture system of fish and aquatic organisms and their types were also described.
Carps form the mainstay of aquaculture in India contributing over 85% of the total aquaculture production There are 61,259 species of vertebrates recognized world; over 30,700 are fish species of which 8,411 ore fresh water while 11,650 are marine. In India 2,163 spp. are fin fishes have been recorded from upland cold water (157; 7.26%) warm water of the plain (54; 20.99%), Brackish water (182; 8.41%) and marine environment (1,370; 63.43%). Some of these species are cultured at commercial level which covering a lot varieties of fin fishes The three Indian major carps, namely Catla (Catla catla), Rohu (Labeo rohita) and Mrigal (Cirrhinus mrigal) contribute the bulk of production to the extent of 75 to85 percent of the total fresh water fish production, the three exotic carp such as Silver carp (Hypophthalmichthys molitrix) and Common carp (Cyprinus carpio ), Grass carp (Ctenopharyngodon idella )form the second important group to incorporate several other medium and minor carp and into the carp poly culture system several method were used because of their region specific consumer preference and higher market demand.
History
Carp culture in India was restricted only to a homestead backyard pond activity in west Bengal and Odisha until late 1950 s with seed from riverine sources as the only input resulting low level of production the technological breakthrough breeding of carp through hypophysation in 1957 freshwater aquaculture of the country the country till 1984 virtually laid the foundation of scientific carp farming in the country.
Important characteristics of Indian major carps:-
Indian major carp grow fast and can reproduce even in artificial ponds. They feed upon phytoplankton, zooplankton, decaying organic matter, aquatic plant etc. stomach is absent in the alimentary canal of the major carps. Three types of Indian major carps are cultured in
Oysters can change their gender. ...
Humans eat about two billion pounds of oysters every year.
Oysters are very healthy food source, they are loaded with vitamin C, D, and the B vitamins. ...
Clams can live up to 35 years. ...
Clams are high in protein and iron. ...
Lobsters sometimes eat their young.
INTRODUCTION Gorgonians are marine coelenterates (referring to the hollow body cavity) of the class Anthozoa, which include sea fans, sea whips, corals, sea anemones, and other related species.
Gorgonids are soft corals commonly known as sea fans or sea whips, coming under the subclass Octocorallia and have eightfold radial symmetry.
It composed of numerous polyps—cylindrical sessile (attached) forms—that grow together in a flat fanlike pattern.
They are colonial animals that have a beautiful, branching structure that is covered by soft tissue and are generally found in warm waters and around reefs.
it is about the length and weight relationship of fish , growth, length, weight, absolute growth, isometric growth, relative growth, allometric growth,
1. Introduction
2.Principal Game fishes
(a)Fresh water game fishes
(b) Estuarine and sea game fishes
3.Sport Fishing and Tourism
*Mahseer (Barbus Tor) fishing
*Trout fishing
*Sea fishing
THANK YOU!!
Generalized and specific definition of pond and the types relating their size, use, construction method were illustrated. Besides the culture system of fish and aquatic organisms and their types were also described.
Carps form the mainstay of aquaculture in India contributing over 85% of the total aquaculture production There are 61,259 species of vertebrates recognized world; over 30,700 are fish species of which 8,411 ore fresh water while 11,650 are marine. In India 2,163 spp. are fin fishes have been recorded from upland cold water (157; 7.26%) warm water of the plain (54; 20.99%), Brackish water (182; 8.41%) and marine environment (1,370; 63.43%). Some of these species are cultured at commercial level which covering a lot varieties of fin fishes The three Indian major carps, namely Catla (Catla catla), Rohu (Labeo rohita) and Mrigal (Cirrhinus mrigal) contribute the bulk of production to the extent of 75 to85 percent of the total fresh water fish production, the three exotic carp such as Silver carp (Hypophthalmichthys molitrix) and Common carp (Cyprinus carpio ), Grass carp (Ctenopharyngodon idella )form the second important group to incorporate several other medium and minor carp and into the carp poly culture system several method were used because of their region specific consumer preference and higher market demand.
History
Carp culture in India was restricted only to a homestead backyard pond activity in west Bengal and Odisha until late 1950 s with seed from riverine sources as the only input resulting low level of production the technological breakthrough breeding of carp through hypophysation in 1957 freshwater aquaculture of the country the country till 1984 virtually laid the foundation of scientific carp farming in the country.
Important characteristics of Indian major carps:-
Indian major carp grow fast and can reproduce even in artificial ponds. They feed upon phytoplankton, zooplankton, decaying organic matter, aquatic plant etc. stomach is absent in the alimentary canal of the major carps. Three types of Indian major carps are cultured in
Oysters can change their gender. ...
Humans eat about two billion pounds of oysters every year.
Oysters are very healthy food source, they are loaded with vitamin C, D, and the B vitamins. ...
Clams can live up to 35 years. ...
Clams are high in protein and iron. ...
Lobsters sometimes eat their young.
INTRODUCTION Gorgonians are marine coelenterates (referring to the hollow body cavity) of the class Anthozoa, which include sea fans, sea whips, corals, sea anemones, and other related species.
Gorgonids are soft corals commonly known as sea fans or sea whips, coming under the subclass Octocorallia and have eightfold radial symmetry.
It composed of numerous polyps—cylindrical sessile (attached) forms—that grow together in a flat fanlike pattern.
They are colonial animals that have a beautiful, branching structure that is covered by soft tissue and are generally found in warm waters and around reefs.
it is a presentation which talks about 6 marine animals and 4 aquatic plants which are found to live in the Atlantic ocean.
it is a colorful presentation with lots of images to substantiate the information given aside.
Brackish water is a mixture of fresh and salty water which usually occurs in estuaries, and has a salinity usually of between 15 and 30 per thousand, depending on rainfall and freshwater run-off. Some fish species like mullets are able to survive in this environment.
Characteristics - Ariidae Medium to large sized fish.
Two pairs of nostrils closely on each side.
Paired maxillary and mental barbels present totally 4-6.
Dorsal fin short, with long more or less serrated spine preceded by a very short one.
Caudal fin deeply forked.
Adipose fin present.
Pectoral fin low set, with serrated spine.
Colour – Usually greyish blue, dark grey, yellow or brown sometimes with black patches or in some with silvery lateral stripe; pale to white below.
Major Fresh water and Marine Ornamental fishes and Potential for Domestic far...B. BHASKAR
Important fresh water and marine water ornamental aquarium fishes, average economics on setting up of ornamental fish hatchery, proposed unit cost for ornamental fish farming, export potential for Ornamental fish trade
lobsters and crab fisheries in INDIA is a vast and enormous amount of catch and exports are being made.
this slide describes about the methods, distribution, annual landings and important species of lobster and crabs in India.
Introduction The whale shark ,Rhincodon typus are large slow moving filter – feeders that are the largest known living fish in the ocean .
The whale shark has a very widespread distribution and occurs throughout the worlds tropical and warm temperate seas.
The largest confirmed Individual had a length of 18.8 m.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
1. FLAT FISHES &
THEIR FISHERIES
MUNEER .A
Dept. of Aquatic Biology& Fisheries
Muneer.fantasy786@gmail.com
Marine Fisheries
2. • Flatfishes- the common name of the order Pleuronectiformes,
found in all seas.
• These are generally spiny-finned, deep-bodied, laterally highly
compressed fishes with about 570 extant species
• Unique type of fishes due to its flatness and position of eyes
• Both the eyes are placed in one side, either left or right
• Also have some adaptations like pigmentation in the body
corresponding to the surroundings
• Certain species have commercial importance in some area.
• From these, eleven genera and 25 species of flatfishes
contribute to minor or major fisheries along the Indian coast.
3. • Order Pleuronectiformes, or Heterosomata consist of 570 extant
species, recognized approximately 11 families of 123 genera.
• Flat fishes are popular under the common names halibut, plaice,
turbot, flounder and sole.
• The flatfishes are found in all the seas of the world and the
species composition is different in different regions.
• The characteristic features of flat fishes are their asymmetry,
mainly their eyes, both eyes on the same side of the head in
juveniles and adults.
• Eyes are on left side in Psettoididae, citharididae, bothidae ,
achiropsettidae, scophthalmidae, paralichthyidae and
cynoglossidae. On the right side in pleuronectidae, samaridae,
achiridae and soleidae.
4. HABITAT
• inhabit on the continental shelf with shallow, soft
sediments to a depth of about 200 m, also some species
are found in greater depths to about 500 m or more.
• Flatfishes generally lie on the bottom on their blind side.
• They are bottom-dwelling predators, usually found either
lying on top of the substratum or partially burrowing
partially or almost entirely in sand or soft mud with only
their eyes protruding above the substratum.
• found on a variety of substrata including silt, mud, sand
and sand–shell mixtures, with some species also
occurring on rocky or pebbly bottoms.
5. • All flatfishes begin life as pelagic, bilaterally symmetrical
fishes, during larval growth in a few weeks; they are going
through a magnificent ontogenetic change where one eye
migrates from one side of the head to the other at end of
pelagic larval stage.
• Their bodies flatten into an oval shape, one side turns dark
and one side light, and they settle to the bottom of the sea
floor.
• This metamorphosis occurs very rapidly.
6. • Later more changes occur from a regular symmetrical body
in various external and internal structures in the skeletal
and digestive systems,
• including placement of nostrils on the head, differential
development of bones in anterior head skeleton,
• differences in jaw shape and dentition on either side of the
body,
• degree of development of lateral body musculature,
• lateral-line development on either side of the body,
• differential coloration on ocular and blind sides, and
• differences in paired fin development on ocular and blind
sides of the body.
7. ADAPTATIONS
• One of the distinguishing features of the order is the
presence of protrusible eyes- adaptation to living on the
seabed
• The extension of the dorsal fin onto the head.
• All of the flatfishes have a single long dorsal and anal fins
on each edge, both without spines;
• Well-developed ventral fins which are either on the right-
hand edge or on the left-hand edge as the fish lies.
• Most of the species have pectoral fins, one on eyed side
and the other on the blind side.
8. • The ventral fins are in front of the pectorals or in line with
them
• the abdominal cavity is very short
• While one of their eyes migrates around the head until
both the eyes finally come to lie close together
• The mouth retains its original position more nearly, so
that it is often described as opening sidewise.
• The underside of the flatfish is pale and the top is colored
to match the environment;
• some species are able to change their pigmentation,
especially the flounders.
9. FOOD& FEEDING
• Flatfishes are generally carnivorous in nature.
• Mainly feed on the bottom-dwelling organisms
• The dietary components of Malabar sole can be grouped
under major categories like polychaetes, amphipods,
copepods, mysids, small molluscs and detritus.
• Among polychaetes , Prionospia pinnata was found to be
the favorite food as this item was noticed in all the
months.
• This indicate- Malabar sole is a typical bottom feeder
mostly feeding on detritus and macro-benthos.
• P.erumei - feeding predominantly on fishes and
cephalopods with crustaceans and bivalves contributing
the subsidiary food.
10. REPRODUCTION
• A flatfish, as a group, produce a wide variety of egg and
larval forms in the plankton.
• Most flatfish species produce pelagic eggs sizes in range
from 0.5–0.8 mm
• Spawning season varies among flatfish families in
relation to latitude.
• For example, in Pleuronectidae reproduction is restricted
to summer in high latitude waters, while it shifts to
spring and winter in temperate waters.
• But, Soleidae are distributed at lower latitudes and
spawn mainly during summer.
11. • Most species are having one single spawning period
during the year, some flatfish species spawn bimodal.
• The Malabar sole, C.macrostomus has a prolonged
spawning period extending from October to May off
Mangalore and Calicut and peak time is October to
December.
• As in the case of C.dubius, from October to December.
• C.macrolepidotus spawns during January-February and
August off Rameswaram.
• P.erumei has a short spawning period during September
and October off Mumbai.
• Most flatfish species are batch spawners that are they
release batches of eggs.
12. • The relative fecundity-
• Cynoglossus macrostomus: 6,540 -19,890 eggs
• P.erumei : 31,380 -12,19,080 eggs
• Flatfishes generally spawn in water deeper than their
juvenile nurseries
• The size of larval flatfishes at-hatching can vary from
about 2mm to 16 mm and size-at-transformation varies
from about 8 mm to 72 mm in various species.
• Flatfish larvae are weak swimmers in the plankton.
• Peak recruitment of C. macrostomus occurs in
September and October off Mangalore; and of C.
macrolepidotus, during March and September off
Rameswaram.
13. GROWTH AND LIFESPAN
• Cynoglossus macrostomus attains 110 mm and 135 mm at
the end of I and II year, respectively.
• The longevity is about 3 years.The length at first
maturity is 100 to 120 mm, which is about 51% of the L.
• The length at first maturity of C. dubius is 287 mm, which
is nearly 60% of the L. Psettodes erumei attains 220 mm,
420 mm and 550 mm at the end of I, II and III year,
respectively.
• The life span of P. erumei is 4 years.
18. • Globally, Catches of flatfishes stable in recent years with 2% of
total landings.
• Flatfishes belonging to 11 genera and 25 species contribute to
minor and major fisheries along the Indian coast.
• The flatfish landings have increased consistently during the past
few years and reached 53116 t and accounted for 6.22% of total
marine demersal fish landings
• Among all the species of flatfishes occurring along the Indian
coast, it is only the Malabar tongue sole, Cynoglossus
macrostomus that has formed a major fishery for several years,
• especially along the southwest coast and documented at least
from the beginning of this century from the region between
Mulki in Karnataka and Kollam in Kerala.
19. • This is the important zone for the Malabar sole.
• Commonly called nangu in Kerala also called manthal in some
places of Kerala
• This is the most valuable flat-fish commercially in Indian waters.
• The fishing season is from late august or September to
December and the heaviest landings are in the region between
edakad and kadapuram on the Kerala coast.
• The bulk of the catches are obtained at the commencement of
the season.
• The sudden appearance of the tongue-soles in the surface and
subsurface waters of the inshore region is phenomenal and is
known in Kerala as Manthayilakom, when they are captured in
huge quantities in boat-seines (thattum vala, paithu vala), cast-
nets and shore seines (noona vala).
• In the peak of the fishery, 75 to 80% of the fish are fully mature
begin to disappear as suddenly as they appeared at the
commencement of the season.
20. • Psettodes erumei is an important food fish and occurs in small
quantities on both the east and west coasts of India, and also
occurs in deeper waters.
• It forms an important fishery at Maharashtra andTamilnadu
coast.
• Where it is much valued as a food fish.
• It grows to a length of 60 cm, being the largest flatfish of our
area; the zero, one and two year-classes constitute the fishery.
• Cynoglossus dubius, Carrot tongue sole came into some
prominence in the fishery only after the introduction of
mechanized fishing along the Kerala coast.
• This species grows to more than three times to be normal
adult size of the Malabar sole.
• Other flatfishes landed in Indian coast have very little
commercial importance .
21. GEARS
• During the pre-mechnised period, the important gears
used were: cast nets, boat seines (Paithu vala) in Kerala
and shore-seines (rampani=airampani) in Karnataka.
• Certain other gears namely Nethel vala, Pattamkolli vala
and Chooda vala also were used to harvest the sole.
• introduction of mechanization from the sixties, the fishing
pattern has changed, from capturing the shoals at the
surface and subsurface regions by indigenous gears to
effective capture by bottom trawlers.
• the bulk of the Malabar sole caught is by this gear with a
mesh size of 15 to 25 mm operated mostly from small
trawlers of 14 m OAL in the depth zone of 10-50 m
22. PRODUCTIONTRENDS
• The flatfish landings have increased consistently from
2000t in 1951 to 53,116 t in 2014.
• The maximum landing of 63,353 t was in 1992.
• The resource contributed to 1.4% of the total marine fish
landings and 6.22% of the total demersal landings in
India in the year 2014 (CMFRI).,
• Includes 1784 t of Halibut, 244 t of Flounders and 51088 t.
of soles during 2014
• That is, Soles alone contributed to 96.18% of the total
landings of the flatfishes, followed by the halibut (3.4%)
and the flounders (0.4%) in the year 2014.
23. • In Kerala, an estimated 12318 t of flatfish was landed in
2014; catch declined by 4.25% from 2013 and formed
15.17% of the total demersal landings of the year.
• C. macrostomus (78.4%) remained the most important
species in the fishery in all gears followed by C.
macrolepidotus (10.9%) and C. bilineatus (10.7%).
• Length range of C. macrostomus in the fishery was 22 to
178 mm with recruitment in April-May and November.
• Fecundity estimated for the species during this period
was 22458 to 52487 eggs.
• The exploitation rate of C. macrostomus was estimated to
be 0.63. [CMFRI]
24. • The substantial increase in the flatfish landings is due to
the intensification of trawling, which is the most effective
method of exploiting this resource.
• Moreover, the trawl operations are known to transform the
sea bottom that is rich in vegetation and invertebrates to
one of sandy wastelands, which have proved to be ideal
habitat for flatfishes.
• In the intense trawling grounds in several temperate seas,
it is reported that the flatfishes thrive well and the landings
of the flatfishes increased despite decline in the landings
of other demersal fishes.
26. GEAR-WISE LANDINGS
• During past mechanization, the Malabar sole
Cynoglossus macrostomus was caught by cast nets, boat
seines and shore seines.
• With the introduction of mechanization, especially the
trawlers in the early 1960s, the fishing pattern changed
from capturing the flatfishes during their halt at the
surface and sub-surface waters to effective utilization at
the bottom.
• During 1998-2000, the trawlers contributed to 86.7% of
the flatfish landings along the Indian coast.
• Mini trawls (9.6%), dol nets (1.5%) and drift gill nets
(1.0%) were the other gears, which contributed to the
fishery.
27. SPECIES COMPOSITION
• Among all the species of flatfishes occurring along the
Indian coast, it is only the Malabar sole, C.macrostomus
that has formed a major fishery mainly in kerala-
karnataka coast
• where as Cynoglossus bilineatus dominated (94%) the
fishery in the southern part ofTamil Nadu.
• A larger growing species C. dubius also contributes to a
minor fishery along the coasts; and
• small numbers of species such as C.lida,C. punticeps, C.
bilineatus, C. arel, Paraplagusia and Pseudorhombus are
reported to appear in small quantities in Karnataka.
28. • Species of Solea, Synaptura and Pseudorhombus are
occasionally taken in small quantities from inshore
catches, especially S. ovate, Pseudorhombus arsius and
Psettodes erumei, (Indian halibut) occurring in small
quantities along both the coasts and recorded from
deeper areas also.
• Along the east coast P. erumei and C. arel, C. bilineatus,
C.punticeps are found in landings.
• P.erumei and Pseudorhombus and Heteromyceterias at
mandapam;
• while the other species that have occurred there
seasonally are C. lida, Pseudorhombus malayanus and
Laepos nigrescens.
29. LENGTH COMPOSITION
• The length range of C.macrostomus was 40-169 mm in
the trawl landings at Mangalore, Calicut and Cochin.
• The annual mean length ranged from 90 to 127 mm.
• The length range of C.bilineatus was 111-380 mm and
• the mean annual length was 198-205 mm, and
• C.macrolepidotus was 90-420 mm indicating an annual
mean length of 237-243 mm.
30. UTILIZATION
• Most of the flatfishes have unique taste and have low fat
content and have white flesh.
• So this fishes have food value globally.
• The meat from a flatfish typically varies in color, fillets
from the bottom (white) side of the fish will be thinner
and whiter, while fillets from the top (dark) side will be
thicker and grayer.
• Large-sized flatfishes such as the halibut there is
demand in the market, small sized species like the
Malabar sole have less preference.
• About 90% of the small-sized flatfishes are salted and
sundried and sold during non-fishing seasons.
31. MANAGEMENT
• No evidence of overexploitation of flatfishes along the
Indian coast, it is essential to adopt a precautionary
approach for sustaining the stocks.
• However, no fishery targets the flatfishes and they are
by-catch of the trawls.
• The bulk of the catches for these resources are
bycatches in the fisheries targeted for other resources
such as shrimps.
• The effect of fishing on the stock of Malabar sole
available at Calicut is negligible and that the present
fishing effort there can be Increased two-fold ,
32. • However, the studies undertaken at Mangalore Indicate
that the present exploitation rate there for Malabar sole
is about the optimum.
• Studies on yield -mesh curve at Mangalore also indicate
that any change from the present length will only reduce
the yield per recruit.
• Unwanted catches throughout the year may cause the
exploitation of flat fish juveniles;
• it’s affect the recruitment of fishes, so causes the
degradation of population.
• Hence, it may not be possible to implement management
measures exclusively for the flatfishes.
33. • The management of flatfish stocks could be a part of an
ecosystem based fisheries management consideration,
wherein ecosystems may be delineated based on the
carrying capacity vis-à-vis exploitation,
• and the climatic, hydrographic and biological
characteristics of each ecosystem.
• Eco-groups may be identified in each ecosystem based
on their habitats and their trophic level; and
• The appropriate fisheries management option for each
ecosystem, by way of closed season, mesh regulation,
closed area or by demarcating no-fishing zone, may be
implemented depending upon the status of exploitation
of the eco-groups.
34. CONCLUSION
• The flatfishes are benthic, carnivorous, belong to the
Order Pleuronectiformes have both the eyes on one side of
the laterally highly compressed body, this group include
the flounders, halibuts, soles, plaice, dabs and turbots.
• The flatfishes begin their life as a normal pelagic fish and
occur sudden metamorphosis and one eye migrates other
side and the body become flat, also fish moves to bottom.
• Flatfishes contribute 2% of the total global landings.
• The landings increased after the introduction of
mechanized vessels and gears.
35. • Major fishery is associated with Malabar sole, it
contribute the ~90% of the total flatfish landings.
• In India, the flatfish landings have increased consistently
from 2000t in 1951 to 53,116 t in 2014.
• contributed to 1.4% of the total marine fish landings
• The maximum landing of 63,353 t was in 1992.
• The management and conservation plans are not
available specifically for flatfishes because this is not a
target group, a bycatch on trawl for shrimp etc.
• But, like any other dimersal fish, flatfishes also face
degradation due to pollution, habitat degradation and
the exploitation of juveniles; this is affect on the
recruitment.