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ThesisItem Open Access STUDIES ON BIOLOGICAL ASPECTS AND BODY COMPOSITION OF NON-CONVENTIONAL FISH, RED-TOOTHED TRIGGERFISH ODONUS NIGER (RUPPELL, 1836) ALONG MANGALURU AND MALPE COAST(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2021) SUYANI NITIN KANJI; MRIDULA RAJESHThe red-toothed triggerfish (Odonus niger Ruppell, 1836) is a demersal reef associated fish of the tropical Indo-Pacific area, found at a depth of 5-40 m. The body is blue, the fins are blue-green with blue edge, mouth is small and prominent, the caudal fin is C-shaped and well-developed dorsal fin spines to protect themselves from predators. The present study was based on the observation of 358 individuals (15.4 to 24.0 cm TL) comprising of 257 males and 101 females. The “r” value indicated that the most highly correlated body parameter in relation to TL was standard length (r = 0.91, p<0.01). Four out of eight morphometric characters were environmentally controlled, indicating a wide range of zoogeographical distribution of the species. ANCOVA showed no significant difference (p>0.05) between sexes, therefore, a common equation of LWRs was derived as: W = 0.04705 L2.56089. The Kn indicated almost identical condition for both the sexes. Analysis of gut contents specify that the fish is truly an omnivore and the diet was composed of crustacean remains (51.50%), zooplankton (19.97%), algae (17.70%), squid remains (4.93%), fish remains (3.70%), partially digested matter (2.16%) and detritus (0.24%). The overall sex-ratio of M:F was 1:0.39. Maturity stages indicated that the species spawns for a prolonged period, extending from November to March. Lm50 revealed that the males mature earlier than females. Absolute fecundity ranged from 16,464 to 1,01,962 eggs with an average of 49,467 ± 21675 eggs/female. Ova diameter ranged from 0.01 to 0.28 mm. The HSI values exceeded the GSI in all the months. The muscle composition revealed that the fish has high protein and low fat content and hence regarded as lean fish. Ash content of the species indicated high content of minerals. The present study revealed that O. niger could be a potential source of ω3 fatty acids as well as essential amino acids and micro nutrients such as potassium, phosphorus, sodium, magnesium and calcium.ThesisItem Open Access “STUDIES ON THE FISHERY AND BIOLOGY OF OBTUSE BARRACUDA, SPHYRAENA OBTUSATA [CUVIER, 1829] ALONG MANGALURU AND MALPE COAST”(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCE UNIVERSITY, BIDAR, 2021) MESHRAM MONTI MADAN; MRUDULA RAJESHThe obtuse barracuda, Sphyraena obtusata (Sphyraenidae), is a pelagic species found in the tropical oceans around the world. It is a voracious feeder, feeding on fishes, crustaceans and cephalopods. A total of 352 individuals of S. obtusata were analyzed which comprised of 162 males and 190 females. The comparison of different morphometric characters with total length showed high values of correlation (0.708-0.985). Analysis of meristic characters indicated that the number of spines on dorsal fin 1 (5), dorsal fin 2 (1), ventral fin (1) and anal fin (2) and number of rays on dorsal fin 2 (9), ventral fin (5) and caudal fin (17) and number of gill rakers (2) on first gill arch remained constant throughout the study. The length-weight relationships showed no significant difference between male and female and thus a common equation derived for pooled data was W = 0.01786 L2.6815 (r2 = 0.9658, n = 352). The value of relative condition factor (Kn) varied from 1.00097 ± 0.04509 to 1.00153 ± 0.05640. Gut content analysis revealed that 118 stomachs (33.52 %) were empty and 234 stomachs (66.48%) contained food in varied quantity. Index of relative importance (IRI) showed highest value for fishes (93.76%) followed by crustaceans (6.09 %) and cephalopods (0.15%). The reproductive biology of S. obtusata revealed that there are seven maturity stages in female and five maturity stages in male. The sex ratio skewed towards females with an overall ratio of 1:1.17 (Male: Female). The spawning season of S. obtusata was observed during September to December. The size at first maturity of male and female was found to be 21.3 and 21.1 respectively. The absolute fecundity ranged from 91,942 to 1,34,445 with an average of 1,12,878 ± 2,763. The ova diameter ranged from 0.02 to 0.48 mm. The gonadosomatic index (GSI) ranged from 1.23 ± 0.23 to 3.64 ± 0.98 for male and 1.31 ± 0.21 to 3.8 ± 0.39 for female. The proximate composition of S. obtusata showed 76.87 to 78.0 % moisture, 20.01% to 21.39% protein, 0.82% to 1.21% fat and 0.92% to 1.19% ash.ThesisItem Open Access ASSESSMENT OF ICHTHYOFAUNAL BIODIVERSITY OF SWARNA RIVER ESTUARY OF UDUPI DISTRICT IN KARNATAKA.(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2021) HARSHATH, D.G.,; H.N.ANJANAYAPPAThe coastal ecosystems of Karnataka are situated closer to the Western Ghats, which are considered as one of the global biodiversity hotspots. In view of this, the present study was conducted on the ichthyofaunal diversity of estuarine system of Kodi-Bengre region, which gives important insights on the abundance and seasonality of fish diversity.From August 2019 - March 2020, a total of 65 species encountered belonging to 50 genera, 37 families and 11 orders were studied. Among them, Nematalosanasus was found to be the most dominant species. Out of 10 orders, the order Perciformes stands first, comprised of 22 families represented by 36 species and the order Clupiformes ranked second with 2 families represented by 6 species. The seasonal abundance of ichthyofaunal diversity recorded during post-monsoon (Oct-Jan) is more compared to pre-monsoon (Feb- March) and monsoon (Aug-Sep). The diversity indices including Margalef's richness index (d). Shannon-wiener index (H') (at log 10), Simpson index (A) and Pielou's evenness (J) were calculated. The K- dominance curve plot showed that the diversity of species was high near the bar mouth region and at the estuarine region. These showed the closely similar diversity and proved that the number of species (richness) is more near the bar mouth region. Bray-Curtis similarity index revealed that the maximum similarity was found between pre-monsoon and monsoon seasons at S2 and S1 station. And the same pattern was also evident in the MSD plot and the stress valve, which was overlain on the MSD plot (0.13, 0.1 and 0.09), showed a good ordination of the samples collected.Biodiversity of threatened ichthyofaunal species out of the recorded 65 species, 25 species were Not Evaluated, 35 species were Least Concern, 3 species were Data Deficient, 1 species was Vulnerable, and 1 species Critically Endangered was recorded from the Swarna River estuary.ThesisItem Open Access TO STUDY DIFFERENT PRESERVATION TECHNIQUE IN FISH FOR ACADEMIC USE(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2021) HARISHA; KUMAR NAIKThe fishes like Clarias batrachus, Rastrelliger kanagurta, Gerres filamentosus, Nemipterus japonicus, Etroplus suratensis and Rhabdosargus sarba were preserved by using plastination technology. They were collected from fish stall centers, dissected and were fixed with 10% formal saline for 3 days. Dehydration was carried out in four changes of pure acetone for a period of 7 days depending on the size of the specimen. Impregnation was carried out by using combination of 15% tea cups and thermocol solutions prepared by recycling plastic tea cup and thermocol at room temperature for 15 days. Various fishes like Clarias batrachus – 67.70%; Rastrelliger kanagurta – 63.21%; Gerres filamentosus – 65.18%; Nemipterus japonicus – 67.86%; Etroplus suratensis – 61.83% ; and Rhabdosargus sarba - 64.97% showed over all shrinkage percentage at room temperature. The color change was black in Clarias batrachus; slightly whitish in Gerres filamentosus; and slightly yellowish in Nemipterus japonicus against their normal color. But there was no change in any morphological details except hardening. Another new innovative technique was developed for preservation of the specimens. i.e., The Elnady technique or Glycerin dry mount method. The fishes like Rastrelliger kanagurta and Gerres filamentosus were collected from fish stall centers. Elnady technique was carried out by using pure glycerin in impregnation and corn starch in curing step. Two Rastrelliger kanagurta and one Gerres filamentosus fishes were preserved. Rastrelliger kanagurta (A) – 21.00%; Rastrelliger kanagurta (B) – 20.91% and Gerres filamentosus – 8.33% showed over all shrinkage percentage at room temperature. The color was normal and consistency became soft and flexible.ThesisItem Open Access “STUDIES ON BIOLOGICAL ASPECTS OF THE MOON FISH, MENE MACULATA (BLOCH AND SCHNEIDER, 1801) OFF MANGALORE COAST”(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, KARNATAKA, 2019) Sneha Darshan, C.,; H.N.ANJANAYAPPAThe moon fish, Mene maculata is belonging to the genus Mene, family Menidae, and order Perciforms, popularly called moon fish. The present study based on the observation of a 452 total individuals ranging from 11 to 27 cm size, comprising 227 males and 225 females were collected fortnightly from Mangaluru landing centre. The length-weight relationship of M. maculata did not show any significant difference between sexes and pooled equation were drawn Log W= 0.0276 + 2.8567 Log L. The relative condition factor (Kn) values for male and female varied from 1.055-1.059 respectively. The qualitative and quantitative analysis of gut content showed that the fish mainly fed on crustaceans, fishes and occasionally on mollusks, occurrence of the mud and sand particles in the gut indicated that the fish is bottom feeder. Active feeding observed during November and December which coincides with the post- spawning season, poor feeding was noticed in the month of February and April which indicates breeding season of the fish. The overall Sex- ratio was estimated as male: female = 1:0.99. The length at 50 % maturity was found to be 19-21 cm (TL), for male and female respectively. The Gonad-Somatic Index values ranged from 0.3794 to 2.5485 in male and in case of female, it fluctuated between 0.4245 to 3.3315. Fecundity of M. maculata varied from 1,01,051 to 2,38,875 eggs with an average of 1,66,962 eggs/female depending upon the size of the fish. The ova diameter ranged from 0.04 to 0.91mm. The species is a prolonged spawner. The proximate composition revealed that the Moisture has 71.10 %, followed by protein 23.29 %, ash 3.97 %, and fat 1.91 %.ThesisItem Open Access “STUDIES ON SOME BIOLOGICAL ASPECTS OF THE BLACK BANDED TREVALLY, SERIOLINA NIGROFASCIATA (RUPPELL, 1982) ALONG THE MANGALURU COAST”(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2018) KALAVATHI N.R.,; MANSING NAIK)The black-banded trevally, Seriolina nigrofasciata found In indo-west pacific, from eastern coast of Africa to Australia, north to southern Japan. Seriolina nigrofasciata (order: perciformes, family : Carangidae ) is a non-schooling carangid fish which occurs at the depth from 20-150 m and is commonly found in offshore reefs over the continental shelf on rocky bottom. This species is also called as “black banded king fish or butter fish” and locally called as “Neyyi meenu”. The present study is based on the observation of a total 627 individuals ranging in size from 15 to 63 cm total length (TL) comprising 280 males and 347 females. The length-weight relationship for male was W= 0.0179L2.9596 and for female W=0.0186L2.9156 . The relative condition factor (Kn) values for male and female varied from 0.9727 and 1.3307 respectively. Analysis of the gut content indicated that fish is carnivore and the diet was composed of Semi-digested matter 68.04 %, teleost 20.80 %, molluscans 16.66 %, crustaceans 3.49 %. The size at the first maturity for male and female appeared at a length of 36 cm and 39 cm TL respectively. The sex-ratio of male:female was found to be 1:1.23 in the commercial catches, showing dominance of female in the population. The Ganado-Somatic Index values ranged from 0.2149 to 2.1769 in male and in case of female, it fluctuated between 0.2342 to 3.9696. The fecundity ranged from 1,92,295 to 7,60,248 eggs with an average 5,02,906 eggs per individual . The ova diameter ranged from 0.01 to 0.5mm. The maturity stages of Seriolina nigrofasciata indicated that this species is a annual single spawner during November to febraury. Proximate composition revealed that fish muscle has 74.03 % to 83.12 % moisture, 14.58 % to 21.87 %. protein, 0.57 % to 3.66 % fat, and 0.86 % to 1.64 %. of ash.ThesisItem Open Access TROPHIC INTERACTION IN COMMERCIALLY EXPLOITED DEMERSAL FINFISHES WITH EMPHASIS ON ONTOGENIC DIET SHIFTS(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2018) BHAVANJALI M.R; MRIDULA RAJESHTrophic interactions in seven commercially exploited marine demersal finfishes of Karnataka were studied to understand the trophic organization with an emphasis on ontogenic diet shifts and trophic overlap. In total, 4723 stomachs were examined of which 73 prey items were identified. Crustaceans and fishes formed the major prey item. Based on cluster analysis of predator feeding similarities and ontogenic diet shift within each predator, two major trophic guilds were identified. The first guild of ‘crustacean feeders’ included all size groups of Nemipterus japonicus, N. randalli, O. cuvieri and Priacanthus hamrur. The second trophic guild, ‘piscivores’, was mainly made up of larger size groups of all predators and all size groups of Saurida tumbil and S. undosquamis. The mean diet breadth and mean trophic level showed a strong correlation with ontogenic diet shift. TROPH values ranged from 3.4-4.6 for species indicating carnivorous diet pattern of the species. All the species were carnivores and the extent of carnivory increased with ontogeny. It is clear from the present study that most of the species when they were young preferred crustaceans, other invertebrates and smaller fishes but the preference changed for teleosts and other carnivores as they grew in size and age. A seasonal variation in the diet pattern observed was due to variations in prey abundance. Trophic network analysis showed maximum prey in Trophic level III and any alterations due to ecological or anthropogenic activities affecting the prey would result in alterations in community dynamics of the predators.ThesisItem Open Access STUDIES ON PLASTIC POLLUTION AND IT’S IMPACT ON BIOLOGY OF COMMERCIALLY IMPORTANT FISHES OFF MANGALURU COAST(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2019) YASHWINI, Y. MUTTA; S.R.SOMSHEKARThe issue of plastic pollution in the marine environment has already created a menace across all the coastal areas of the world. Monitoring is crucial to assess the efficacy of measures implemented to reduce the abundance of plastic debris. Sources of plastic marine debris found on the selected 3 stations along the Mangaluru coast were estimated. Samples were collected from 5 quadrats of 2 × 2 m for each station from January 2019 to July 2019. The total number of plastic debris varied between months and between stations with 70-224 nos. This has lead to a much larger concern regrading the presence of microplastics (MPs) (plastic debris <5mm) and its ingestion by the marine fauna. This study focuses, for the first time, on the presence of microplastics in stomach contents of 8 commerically important fishes along the Mangaluru coast, India. A total of 240 fishes were examined out of which 46 (19.16%) guts had microplastics in them. Microplastics found were of two types, fragments and fibres. The total number of microplastic found were 54, out which 87% (47) were fibres and 13% (7) were fragment, their size ranged between 0.1mm – 3.7mm. The presence of secondary microplastics in the fish has shown that the microplastic pollution of the area is mainly due to the coastal plastic pollution. These results are very important to crub plastic and microplastic pollution around the coastline, and public awareness of the harmful effects of these microplastics is neededThesisItem Open Access ASSESSMENT OF ICHTHYOFAUNAL DIVERSITY IN ESTUARINE SYSTEM OF KUNDAPURA REGION.(KARNATAKA VETERINARY, ANIMAL AND FISHERIES SCIENCES UNIVERSITY, BIDAR, 2019) PRASHANTH, R.,; H.N.ANJANAYAPPACoastal ecosystems of Karnataka situated closer to the Western ghats which are considered as one of the global biodiversity hotspots. In view of this, this study on ichthyofaunal diversity of estuarine system of Kundapura region gives important insights to the abundance and seasonality of fish diversity. From August 2018 - May 2019, a total of 64 species encountered that belonging to (49) genera, (36) families and (10) orders. Among them, Nematalosa nasus was found to be the most dominant species. Out of 10 orders, the order Perciformes stands first, comprised of 23 families represented by 37 species and the order Clupiformes ranked second with 3 families represented by 8 species. The seasonal abundance of ichthyofaunal diversity recorded during pre-monsoon (Feb-May) > post-monsoon (Oct-Jan) > monsoon (Aug-Sep). The diversity indices including Margalef’s richness index (d), Shannon-wiener index (H') (at log 10), Simpson index (ʎ) and Pielou’s evenness (J') were calculated. The K- dominance curve plot showed the diversity of species was high near the estuarine region and at the bar mouth region. These are showing closely similar diversity and proved that the number of species (richness) more near the estuarine region. Bray-Curtis similarity index revealed that the maximum similarity was found between pre-monsoon and post-monsoon seasons at S2 and S1 station. The same pattern was also evident in the MSD plot and the stress valve, which was overlain on the MSD plot (0.1, 0.1 and 0.08), showed a good ordination of the samples collected. Panchagangavalli estuary gives breeding and feeding ground for many commercially important fishes, In fisheries point of view it is a very sensitive zone, So it should be protected from all man-made disturbance legitimately, to enrich and sustain the biodiversity for the future.
