Gonadal Maturation Stages Research Articles

Factors influencing beak morphology of Sthenoteuthis oualaniensis in the northwest Indian Ocean.

With 1009 Sthenoteuthis oualaniensis samples collected by Chinese light falling-net fishery during February to May in the northwest Indian Ocean, we analyzed the influencing factors of the morphology change of the beak. There were significant differences in the morphologic growth between genders, different gonad maturity stages, and different mantle length. The increment of characteristic parameters growth peaked in the mantle length between 201 and 250 mm, and in the Ⅱ and Ⅲ stages of gonad maturity for females and males, respectively. There was no significant difference in the ratio of morphometric parameters to crest length (CL) between the genders, diffe-rent gonad maturity stages, and different mantle length, except for the ratio of upper hood length to upper crest length (UWL/UCL) and lower hood length to lower crest length (LHL/LCL). The ratio of each characteristic parameter to CL was nearly stable with the change of sex, gonad maturity and mantle length, suggesting consistent growth of each dome of beak. Our results suggested the mantle length of 201 mm to 250 mm seemed to be the threshold for the morphologic growth of beak on the body size, while the gonad maturity of Ⅱ and Ⅲ stages seemed to be the threshold for the morphologic growth of beak on the gonad maturity.

Effect of different doses of 17α-methyl testosterone (17-α MT) hormone on male broodstock of tiger shrimp Penaeus monodon sperm quality

This study aimed to determine the optimum dose of 17α-MT hormone to improve male shrimp P. monodon sperm quality. Male tiger shrimp P. monodon originated from pond with an average weight (57.56 ± 12.79) g were transferred to hatchery and acclimated for 1 week prior treatments. Shrimps were set up in controlled tanks in 5 shrimps/tank density. Treatments were 17α-MT hormone induction in different doses, i.e. A = control (ablation); B = 200 ng/100 g of broodstock body weight (BW); C = 300 ng/100 g BW; and D = 400 ng/100 g BW. The 17-α MT hormone was given using injection method every 7 days in 3 times frequency. Research was completely randomized designed with 4 treatments and 2 replications. Observed variables were: the amount of shrimps which carried spermatophores, weight of spermatophores, quantity of spermatozoa, spermatophores histology and water quality. Data of the amount of shrimps which carried spermatophores, weight of spermatophores and the quantity of spermatozoa were analyzed using analysis of variance (ANOVA), while data of spermatophores histology and water quality were analyzed descriptively. The amount of shrimps which carried spermatophores and weight of spermatophores were not significantly different (P>0.05), but spermatozoa quantity was significantly different (P<0.05). The highest spermatozoa quantity was obtained at 300 ng/100 g BW dose in fourth gonad maturity stage. The 17α-MT in 300 ng/100 g BW was the optimum dose for P. monodon sperm quality improvement and it could be applied to replace ablation method.

REPRODUCTIVE BIOLOGY OF THE FRESHWATER CLAM POKEA (Batissa violacea var. celebensis, VON MARTEN 1897) (Bivalvia: Corbiculidae) IN THE POHARA RIVER, SOUTHEAST SULAWESI, INDONESIA

The freshwater clam, locally known as Pokea, (Batissa violacea var celebensis, von Martens 1897; Bivalvia: Corbulidae) is a popular and widely consumed food in Kendari, Southeast Sulawesi. Despite its popularity, basic information required for conservation managenment, such as reproductive biology, is lacking. This study aims to examine the reproductive biology of the clam obtained from the Pohara River, Kendari. Pokea samples were collected monthly from February 2012 to January 2013. We recorded parameters of reproductive biology, including sex ratio, stage of gonadal maturity, gonadosomatic index (GSI), fecundity, and size of the first mature gonad from each sample. Data were analysed using chi-square test and linear regression in the package Sigma Plot v.6.0. Pokea population in the Pohara River was male-biased. The population spawns throughout the year and the peak spawning season was August-September. Mature gonad was found at small shell size (indicating early sexual maturity). Food availability might have influenced the gonadal development in Pokea. This baseline information is very relevant for conservation practices of Pokea population in the Pohara River.

REPRODUCTIVE BIOLOGY OF THE FRESHWATER CLAM POKEA (Batissa violacea var. celebensis, VON MARTEN 1897) (Bivalvia: Corbiculidae) IN THE POHARA RIVER, SOUTHEAST SULAWESI, INDONESIA

The freshwater clam, locally known as Pokea, (Batissa violacea var celebensis, von Martens 1897; Bivalvia: Corbulidae) is a popular and widely consumed food in Kendari, Southeast Sulawesi. Despite its popularity, basic information required for conservation managenment, such as reproductive biology, is lacking. This study aims to examine the reproductive biology of the clam obtained from the Pohara River, Kendari. Pokea samples were collected monthly from February 2012 to January 2013. We recorded parameters of reproductive biology, including sex ratio, stage of gonadal maturity, gonadosomatic index (GSI), fecundity, and size of the first mature gonad from each sample. Data were analysed using chi-square test and linear regression in the package Sigma Plot v.6.0. Pokea population in the Pohara River was male-biased. The population spawns throughout the year and the peak spawning season was August-September. Mature gonad was found at small shell size (indicating early sexual maturity). Food availability might have influenced the gonadal development in Pokea. This baseline information is very relevant for conservation practices of Pokea population in the Pohara River.

Growth pattern, condition factor and reproductive aspects of three spot gourami Trichopodus trichopterus (Pallas, 1770) in mangrove waters of Muara Angke Jakarta and Ciperet Cilacap, Indonesia

Mangrove ecosystem is a unique and interesting ecosystem which inhabited by many fish species such as three spot gourami (Trichopodus trichopterus). This study aimed to determine length-weight relationship (LWR), growth pattern, condition factor, sex ratio and gonad maturity stage of three spot gourami from mangrove waters of Muara Angke Jakarta and the Ciperet Cilacap, Indonesia. Fish samples were collected by cast net and gill net at four research stations in Muara Angke and Ciperet Cilacap from January to March 2014 and September to October 2012, respectively. The total length and total wet weight were measured, subsequently, the sex and stage of gonad maturity were morphologically determined. The LWRs of three spot gourami in Muara Angke were W = 6E-05L2893 for male and W = 0,0003L2619 for female, whereas, the LWRs of male and female in Ciperet estuary were W = 0,0007L2371 and W = 0,0006L2444, respectively. Moreover, the growth pattern of the male one in Muara Angke was isometry, while the female was negative allometry. In Ciperet estuary, the growth patterns for male and female were negative allometric. The Fulton’s condition factors for males and females in the Muara Angke were ranged from 3.7118±0.7847 and 1.0014±0.0551, respectively. Whereas, in the Ciperet estuary, the condition factor values were ranged from 1.0011 ± 0.0485 and 1.0024 ± 0.0685 for males and females, respectively. The sex ratio for males and females on the Chi-square test with a confidence interval of 95% (α = 0.05) was significantly different by 1:1.93 in Muara Angke and 1:1.69 in Ciperet estuary. In both areas, various maturity stages of gonad were found, with different dominant maturity stage. In Muara Angke, most of the fish were at higher gonadal maturity stages (III and IV), whereas in Ciperet estuary the lower gonadal maturity stages (I and II) was found.

Reproductive biology of hampala barb (Hampala macrolepidota Kuhl & Van Hasselt 1823) in Ranau Lake, Indonesia

One of the economically valuable consumption fish in Ranau Lake is the hampala barb (Hampala macrolepidota). Hampala barb is the top predator in Ranau Lake. The fish population is still quite a lot, but it is starting to decline. This study aimed to determine the reproductive biology of hampala barb in Ranau Lake. Ranau Lake is located in South Sumatra Province and Lampung Province, Indonesia. The research was conducted by the inventory survey method and laboratory analysis. Fish samples were obtained from fisher’s catch, where the fish were caught using gill nets with varying mesh sizes and harpoon. The fish were measured for length body and total weight. Then surgery was performed to determine their reproductive biological characteristics (sex, size of first gonad maturity, gonad maturity stage, Gonad Somatic Index, fecundity, and egg diameter). The results showed that the hampala barb in Ranau Lake laid the eggs throughout the year with a sex ratio of 1: 1, the size of the first stage of gonad maturity of male and female were 15.38 cm and 19.21 cm, fecundity between 17,406-63,793 eggs, and egg diameter between 0.8-1.9 mm. This reproductive biology information can be used for the management of hampala barb in Ranau Lake.

Female Songbirds Can Initiate the Transition from a Migratory to a Reproductive Physiology during Spring Migration.

AbstractThe high energetic costs of both migration and reproduction and the physiological changes to support these costs suggest that these life-history stages should be compartmentalized with little overlap between stages. In contrast, previous studies have shown that male birds can initiate reproductive development during migration before arrival on the breeding grounds with increases in plasma testosterone levels and testis size. However, sex differences in seasonal gonadal function are now recognized as profound, and few studies to date have shown that females can initiate the costly, but critical, estrogen-dependent final stages of gonadal maturation and changes in liver function (yolk precursor synthesis, vitellogenesis) while on migration. Here, we show that female yellow warblers (Setophaga petechia) arrive on the breeding grounds with elevated plasma triglyceride levels compared with males. Some females had plasma triglyceride levels of 5-7 mmol L-1, suggesting that they arrived in a relatively advanced stage of yolk precursor production. Furthermore, we show that females that arrived with higher plasma triglyceride levels took less time to initiate their first clutch. Adaptive plasticity in the timing of the transition from a migratory to a reproductive physiology might help migrant birds buffer against a mismatch between timing of arrival and conditions on the breeding grounds and allow them to advance timing of breeding to maximize breeding productivity.

Egg diameter of female silver rasbora (Rasbora argyrotaenia) at different gonadal maturity stage

As a new aquaculture species, silver rasbora (Rasbora argyrotaenia) has a high demand for consumption and ornamental fish in Indonesia and its surroundings. The aim of this study was to measured egg diameter in female silver rasbora at different maturity stages. This study was conducted in February 2020 at instrument laboratory Universitas Airlangga, Banyuwangi Campus, Indonesia. A total of 16 females of silver rasbora with a weight of 1.73±0.08 g and length of 5.39±0.13 cm was obtained aquaculture installation of Universitas Airlangga, Banyuwangi Campus, Indonesia. Based on the result, the egg diameters were observed in II, III, and IV maturity stage in the amount of 17.96 ± 1.88 µm, 47.15 ± 10.07 µm, and 83.02 ± 4.40 µm. This information will reach our knowing of the maturation cycle of silver rasbora and also improve artificial techniques of culturing fish for commercial purposes and conservation stocking.

Comparison of the catch of two fishing technologies for yellowfin tuna (Thunnus albacares Bonnaterre 1788) in Bone Bay waters, South Sulawesi Indonesia

Yellowfin tuna is one of the important pelagic fishery commodities in the Bone Bay waters, exploited using hand lines and pole and line. This study aims to compare the size structure, the number of the cohort, compositions of catch according to fish maturity stage and percentage of catch suitable size. Fish length data were collected from January to August 2020. Size structure and age groups were analyzed using the Bhattacharya method. The gonad maturity stage observed morphologically using the Schaefer and Orange method, the percentage of catch suitable size using the Mallawa method. The hand line catches measuring 39 to 111 cm, dominant size 49 to 57 cm and 66 to 73 cm, consisting of three age groups and dominated by young. The pole and line catch measuring 34 to 87 cm, dominant size 35 to 37 cm, consisting of three age groups and dominated by the young fish. The percentage of catch suitable size in both fishing technologies is low.

Gonad maturity and gonadal somatic index of blue swimming crab Portunus pelagicus harvested from Spermonde Archipelago, South Sulawesi, Indonesia

Reproductive biology is one of the biological aspects that needed to formulate responsible management of blue swimming crab (BSC). The crab is one of the commercial fisheries commodities in South Sulawesi, Indonesia. Presently no information on the reproductive biology of this crab from Spermonde Archipelago, Sout Sulawesi. Therefore, the study aimed to analyze and compare gonad maturity stage(GMS)andgonadalsomaticindex(GSI)oftheBSCcaughtonthreeecosystemsnamelycoralreef,seagrass,andmangrovein Salemo Island, Spermonde Archipelago. GMS and GSI were analyzed descriptively for five months from March to July 2015. Results indicate there was a difference in GMS of the BSC caught in mangroves, seagrass, and coral reef. Generally, mangrove was dominated by immature BSC with GMS I and GMS II, while the BSC caught in the seagrass and coral reef BSC were dominantly mature and spawn GMS III, IV, and V. GSI BSC caught in mangrove ecosystem are smaller than GSI BSC caught in seagrass and coral reef ecosystems. Seagrass and coral reef ecosystems suitable for development no-take zone of the BSC.

Reproductive biology of the anchovy (Stolephorus commersonnii, Lacepède, 1803) and spotted sardine (Amblygaster sirm, Walbaum, 1792) from Tanga Region, Tanzania

The present study investigated the reproductive biology of Stolephorus commersonnii and Amblygaster sirm at two landing sites in Tanga on the northern coast of Tanzania. Fish samples were collected on a monthly basis from ringnets operated by artisanal fishers in the nearby coastal waters. Spawning seasons were determined using gonadosomatic index (GSI) and gonadal maturity stages. The size at first maturity was 57.7 mm and 66.2 mm total length for male and female S. commersonnii respectively. Male and female A. sirm were estimated to attain first maturity at 147.7 mm and 169.2 mm respectively. The spawning seasons of both species were protracted. S. commersonnii demonstrated a year round spawning cycle with peaks in August, October and January. The peak spawning season for male and female A. sirm was recorded in August and September respectively. Both species exhibited skewed size-dependent sex ratios with females predominating in the larger size classes. A. sirm had a higher fecundity rate with a maximum of 96,500 eggs in the largest female fish of 258 mm as compared to S. commersonnii (10,055 eggs) in the largest fish of 98 mm. The mean (±SE) total fecundity of S. comersonnii and A. sirm was 5,134.7 ± 136.9 eggs, and 47,029.03 ± 1,435.13 eggs in females of sizes 68 mm to 98 mm and 170 mm to 258 mm respectively.

Sex ratio and fecundity of Chrysichthys nigrodigitatus (Family - Claroteidae) from Asejire Lake, Nigeria

Sex ratio and fecundity of Chrysichthys nigrodigitatus from Asejire Lake were examined. The length-weight relationship showed that weight was curvilinearly related to standard length. The logarithm transformation of weight against standard length gave a straight-line graph represented by the following equation: Log W = -0.66 + 2.13 Log sl r2= 0.854; (p&lt;0.001) n = 209&#x0D; Males were generally more with a male : female ratio of 1:0.18. The average fish weight was 88.97g (16.28 cm standard length). Sexual maturity was attained at an average size of 45.0g (14.0 cm standard length). Relative fecundity was dependent on body weight and standard length (P&lt; 0.05 and P &lt; 0.01 respectively). Chrysichthys nigrodigitatus expended between 0.75% - 27.30% of body weight in egg production. The condition factor values showed that a female specimen of equal length with a male specimen is heavier. Six gonad maturity stages were identified, ovary and gonad weights increased with stage of maturity.

Distribusi Ikan pada Wilayah Genangan Berbeda di Danau Tempe, Sulawesi Selatan

&lt;strong&gt;Fish Distribution at Different Inundation Areas in Lake Tempe, South Sulawesi. &lt;/strong&gt;Lake Tempe area consists of permanent standing watersand non-permanent area (flooded area). This study aims to investigate the species and its relative abundance distribution, as well as the distribution of size, condition factor, and gonad maturity stage of dominant species at those different areas. Sampling was carried at high water level period (March, June, and August 2017) in 18 stations, stations 1 to 13 represent the non-permanent inundation areas, and stations 14 to 18 represent the permanent inundation area. Fish was caught using various gears. Fish was identified morphologically and the number was counted. The size of the dominant species was measured and the gonad maturity stage was determined. Data were analyzed using descriptive and inferential statistics. The results of this study show that the highest number of species is found in non-permanent inundation areas. Species that are only found in non-permanent inundation areas are &lt;em&gt;Clarias batrachus&lt;/em&gt;, &lt;em&gt;Anabas testudineus&lt;/em&gt;, &lt;em&gt;Pangasianodon hypopthalmus&lt;/em&gt;, and &lt;em&gt;Trichopodus pectoralis&lt;/em&gt;. The dominant fish in the non-permanent inundation area are &lt;em&gt;Oxyeleotris marmorata&lt;/em&gt;, &lt;em&gt;Channa striata&lt;/em&gt;, &lt;em&gt;Oreochromis niloticus&lt;/em&gt;, &lt;em&gt;Trichopodus trichopterus&lt;/em&gt;, and &lt;em&gt;Pterygoplichthys pardalis&lt;/em&gt;. These fishes have contributed significantly to capture fisheries production. The most abundant fish is &lt;em&gt;Barbonymus gonionotus&lt;/em&gt;. The condition factor and the gonad maturity stage of the &lt;em&gt;B. gonionotus&lt;/em&gt;in in the both areas were not significantly different. Larger fishes and higher relative abundance of &lt;em&gt;B. gonionotus&lt;/em&gt;, when the water level was rising, were found in permanent inundation area. It can be concluded that the existence of those different inundation areas is important for fisheries productivity in Lake Tempe

Reproductive Biology of Oci Fish Selaroides leptolepis in Tomini Bay

Local people name Selaroides leptolepis distributed in Tomini Bay as Oci Fish. A study of the fish reproductive biology, which is one aspect of fisheries biology, is crucial to support the implementation of sustainable Oci Fish resource management policies. This study aims to determine the average length at first maturity, gonad maturity stages, and fecundity of the fish in Tomini Bay. Sampling was carried out using a stratified random sampling method from the catches of the fishermen landed in Fish Landing Base Kampung Tenda, Gorontalo City. The time interval sampling was conducted per month during April, May, and June 2020. Fish and egg samples preserved using ice cubes and a 10% formaldehyde solution correspondingly. The results of the study showed that the Oci Fish in Tomini Bay had a length range of the first maturity between 166 and 174 mm with a gonad maturity index ranging from 1.773 to 2.760%. The average fish fecundity was 16623 ± 4850 eggs.

Determination of annual reproductive cycle in male sterlet, Acipenser ruthenus using histology and ultrasound imaging.

The aim of this study was to evaluate seasonal testicular development in the cultured sterlet, Acipenser ruthenus. During annual sexual cycle of male sterlet, stages of gonad maturity were examined using histology and ultrasonography approaches. The histology identified males at different stages of maturity among fish sampled monthly. According to the seasonal changes in the testes, reproductive cycle was divided into four stages including resting, pre-spawning, spawning, and post-spawning. The histology examination revealed considerable variation in testicular developmental stages. These changes were identified based on persistent spermatogenesis and asynchronous gonad development in testes, showing that regulation of annual gonadal cycle is influenced by season. Also, the results obtained using ultrasound suggested that reproductive stages can be identified based on morphology and tissue echogenicity. At each phase of testicular development, gonadosomatic index (GSI) and number of spermatogenic cysts were variable. The present study focused on determination of annual reproductive development in cultured male sterlet which clearly identifies reproductive stage in each season as valuable guide for future researches on reproductive biology of sterlet. This study presents basic knowledge about reproductive biology in sterlet contributing to optimal broodstocks management that allows comparison of reproductive development among sturgeon species.

Seasonal Dynamics of the Ratio of Rheoreaction Types of Roach Rutilus rutilus

The seasonal dynamics of the motivational component of rheoreaction (ratio of rheoreaction types) has been studied in roach Rutilus rutilus L. inhabiting the Rybinsk Reservoir, Russia. The circular hydrodynamic tank with limnozone is used. The change in the ratio of rheoreaction types in nonmigratory mature roach may adequately reflect its behavior in the reservoir. The fish sex, stage of gonad maturation, and water temperature had a weak effect on the rheoreaction types and stability of their manifestation.

Length-weight relationship and condition factor of an endemic Lagusia micracanthus Bleeker, 1860 in Rivers of the Maros Watershed

Lagusia micracanthus is one of endemic freshwater fish in Sulawesi. It also has been locally consumed. The purpose of this research was to analyze length-weight relationship and condition factors of L. micracanthus in rivers of the Maros Watershed, South Sulawesi Province . The study was conducted in three rivers, namely Pattunuang River, Bantimurung River and Pucak River. The sampling was conducted monthly from May 2018 to April 2019. Fish samples were collected by an electric shocker (12 V and 9 A). A total of 1850 individual fishes with samples ranging from 31.58-127.79 mm in total length and 0.76-31.07 g in weight. The length-weight relationship was W = 0.00009L2.6241 (r = 0.95) in Pattunuang River, W = 0.0001L2.5237 (r = 0.94) in Bantimurung River, and W = 0.0001L2.4953 (r = 0.92) in Pucak River. The slope (b) values of L. micracanthus obtained a negative allometric growth pattern (b &lt;3). The relative condition factors of L. micracanthus was fluctuated from 0.86 to 1.43 in Pattunuang River, 0.65 to 1.45 in Bantimurung River, and 0.55 to 1.26 in Pucak River. The condition factor increased towards the peak of the spawning season and decreased after the spawning period. The condition factor increased with the increasing of gonad maturity stage up to stage IV and decreased after spawned or stage V.

Intra‐annual changes in reproductive indices of male and female Himalayan snow trout,Schizothorax richardsonii(Gray, 1832)

Periodic changes in reproductive hormone levels, gonadal histology and gonadosomatic index (GSI) of snow trout, Schizothorax richardsonii, were examined to ascertain annual cycle of gonadal development and reproductive status in their natural habitat. In females, there were coherent changes in plasma 17β-oestradiol and vitellogenin along with GSI, oocyte maturation and vitellogenic progression, collectively indicating two distinct maturation peaks during the months of September and February. Coinciding with this, in males, plasma 11-keto testosterone was also noticeably higher during September and February, with highest GSI values in September. However, plasma 17α, 20β-dihydroxyprogesterone levels in males were found to be persistently high from September to February. This observation suggests the potential presence of matured oozing males over a longer period, unlike in females. Overall, the close association between reproductive hormone levels, GSI and gonadal maturation stages in males and females (particularly, the presence of postovulatory follicle complexes) with apparent natural synchronization clearly indicates that S. richardsonii breeds twice in a year, possibly during late September to early November and late February to early April in the coldwater riverine habitats of the Indian Himalayan region.

Two species of Carcinonemertes Coe, 1902 (Nemertea: Carcinonemertidae) infesting the Caribbean spiny lobster, Panulirus argus (Latreille, 1804) (Decapoda: Achelata: Palinuridae), in Saint Kitts, West Indies

Abstract The Caribbean spiny lobster, Panulirus argus (Latreille, 1804), is an important resource in the Western Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. A nemertean egg predator of P. argus, Carcinonemertes conanobrieniSimpson, Ambrosio &amp; Baeza, 2017, was recorded in Florida in 2017 and Colombia in 2018. This study sought to investigate the presence of C. conanobrieni in P. argus in Saint Kitts and Nevis, eastern Caribbean Sea. Nemerteans were observed in the brood masses of P. argus. Molecular techniques confirmed its presence in the P. argus population on Saint Kitts. Egg, juvenile, and adult stages of C. conanobrieni and of an undescribed Carcinonemertes sp. were found in the brood masses of 27 of 31 (87%) ovigerous P. argus. Differences in the shape of the nemertean egg masses (string versus spherical arrangement) were confirmed as two distinct species of Carcinonemertes Coe, 1902 using molecular analyses. The juvenile stage of the undescribed Carcinonemertes sp. was detected in the gills of 72 of 320 (23%) of the P. argus individuals from Saint Kitts. The prevalence of branchial nemertean infestation was not significantly different among male and female P. argus. Female lobsters with ovaries in early stages of gonadal maturation were more likely to have branchial nemerteans relative to those with ovaries in late stages of maturation, suggestive of nemertean migration from gills to egg mass once the host oviposits. This is the first report of C. conanobrieni in the Caribbean spiny lobster from the eastern Caribbean, which is approximately 1,300 miles from Florida and 1,000 miles from Colombia. This is also the first report of an undescribed nemertean worm in P. argus. The high prevalence of Carcinonemertes spp. in P. argus raises concern for the extent to which these egg predators may be impacting P. argus in Saint Kitts, an important fishery on the island.

Modeling pre-spawning fitness and optimal climate of spotted snakehead Channa punctata (Bloch, 1793) from a Gangetic floodplain wetland of West Bengal, India.

The spawning and well-being of fish in an ecosystem are closely linked to climatic cues, viz., temperature and rainfall. Reduced fitness can affect the reproductive performance and lead to skipped spawning. Benchmarking the threshold fitness required for a fish population to achieve readiness for spawning, and understanding how climatic parameters influence the fitness will aid in predicting the fate of its reproductive success in future climatic conditions. This study determined the threshold condition factor pre-spawning fitness (Kspawn50) at which 50% of the female Channa punctata population can be deemed fit for spawning. The optimal climate within which pre-spawning fitness is attained by this species under Indian climatic conditions was also identified. The study was conducted from June 2015 to September 2016, covering two spawning seasons (June-August) in a Gangetic floodplain wetland of West Bengal, India. The non-parametric Kaplan-Meier method (survival fit) was used for estimation of pre-spawning fitness. "Ready to spawn" females were classified based on binary coding of the gonadal maturity stages. The thermal and precipitation range within which spawning fitness is achieved was identified by using the locally weightedsmoothing technique. Female C. punctata pre-spawning fitness (Kspawn50) ranged from 1.26 to 1.39 with an estimated median of 1.29 units. Temperatures between 29 and 32°C and rainfall above 100mm were conducive to attaining the requisite pre-spawning fitness in C. punctata. This is the first study benchmarking the pre-spawning fitness and optimal climate for C. punctata. Understanding spawning requirements can inform the climate change-induced impacts on reproductive plasticity and evolutionary adaptations of snakeheads in the Ganga river basin.