Hatchery Management

Hatching performance of 35-40 weeks old multi colour broiler breeder normal feathered Nandanam broiler-3, Nacked Neck and Nacked Neck x Nandanam broiler-3 cross was compared. A total of 6813 hatching eggs collected from Nandanam broiler-3, Nacked Neck and Nacked Neck x B3 cross were set for hatching in six consecutive batches. The per cent fertility (P0.05), total hatchability (P0.05) and fertile hatchability (P0.01) were significantly higher for the crosses (77.22±2.17; 64.57±4.09; 83.34±3.06) and Nandanam broiler-3 (73.05±1.52; 55.12±1.42; 75.49±1.66) than Nacked Neck (65.57±3.77; 43.94±5.35; 66.06±4.44). The per cent total embryonic mortality was significantly (P0.01) lesser in crosses (16.66±3.06) and B3 (24.51±1.66) than Nacked Neck (33.94±4.44). It can be concluded that significantly higher per cent fertility, total hatchability, fertile hatchability and lesser per cent total embryonic mortality were recorded in crosses.

Fall-run Chinook salmon (Oncorhynchus tshawytscha) from the Sacramento–San Joaquin River system form the backbone of California's salmon fishery and are heavily subsidized through hatchery production. Identifying temporal trends in the relative contribution of hatchery-versus wild-spawned salmon is vital for assessing the status and resiliency of wild salmon populations. Here, we reconstructed the proportion of hatchery fish on natural spawning grounds in the Feather River, a major tributary to the Sacramento River, using strontium isotope (87 Sr/ 86 Sr) ratios of otoliths collected during carcass surveys from 2002 to 2010. Our results show that prior to the 2007–2008 salmon stock collapse, 55%–67% of in-river spawners were of hatchery origin; however, hatchery contributions increased drastically (89%) in 2010 following the collapse. Data from a recent hatchery marking program corroborate our results, showing that hatchery fish continued to dominate (90%) in 2011–2012. Though the rebound in abundance of salmon in the Feather River suggests recovery of the stock postcollapse, our otolith chemistry data document a persistent decline of wild spawners, likely leading to the erosion of locally adapted Feather River salmon populations. Résumé : Les saumons quinnats (Oncorhynchus tshawytscha) à migration automnale du réseau du fleuve Sacramento et de la rivière San Joaquin forment l'épine dorsale de la pêche aux saumons en Californie et sont fortement soutenus par la production en alevinières. La détermination des tendances dans le temps des apports relatifs de saumons issus d'alevinières et de saumons nés dans la nature est cruciale pour évaluer l'état et la résilience des populations de saumons sauvages. Nous avons reconstitué la proportion de poissons issus d'alevinières dans des aires de frai naturelles dans la rivière Feather, un important affluent du fleuve Sacramento, en utilisant les rapports d'isotopes de strontium (87 Sr/ 86 Sr) d'otolites prélevés durant des relevés de carcasses de 2002 à 2010. Les résultats montrent que, avant l'effondrement des stocks de saumons de 2007–2008, de 55 % à 67 % des frayeurs dans la rivière provenaient d'alevinières; toutefois, l'apport d'alevinières a connu une augmentation très marquée (89 %) en 2010 dans la foulée de l'effondrement. Les données tirées d'une campagne récente de marquage en alevinière corroborent ces résultats, démontrant que les poissons issus d'alevinières sont toujours prédominants (90 %) en 2011–2012. Si la remontée de l'abondance des saumons dans la rivière Feather semble indiquer un rétablissement du stock à la suite de l'effondrement, nos données sur la chimie des otolites documentent un déclin soutenu des géniteurs sauvages, qui mène vraisemblablement à l'érosion des populations de saumons adaptées aux conditions locales de la rivière Feather. [Traduit par la Rédaction]

The California Central Valley contains the southernmost native populations of Chinook Salmon Oncorhynchus tshawytscha, which inhabit a highly variable, anthropogenically altered environment. To mitigate habitat loss and support fisheries, millions of fall‐run hatchery salmon are released each year, often transported downstream to avoid in‐river mortality, with consequences not fully understood. We synthesize historical trends in release location and timing (1941–2017), focusing on outcomes influencing stock resilience, adult straying, and ocean arrival timing. Over time, juveniles have been transported increasing distances from the source hatchery, particularly during droughts. Transport distance was strongly associated with straying rate (averaging 0–9% vs. 7–89% for salmon released on site vs. in the bay upstream of Golden Gate Bridge, respectively), increasing the effects of hatchery releases on natural spawners. Decreasing variation in release location and timing could reduce spatiotemporal buffering, narrowing ocean arrival timings and increasing risk of mismatch with peak prey production. Central Valley salmon epitomize the pervasive challenge of balancing short‐term (e.g., abundance) against long‐term (e.g., stability) goals.

Predation after release is one of the major concerns of hatchery fish conservation and propagation. However, the relationship among the size of hatchery fish, the predator species, and their behaviors in natural environments is largely unknown. To understand the relationship, we conducted predation experiments in outdoor tanks and a semi-natural stream with exposure to local predators. Two different ranges of fork lengths of masu salmon (Oncorhynchus masou) were examined as prey sizes. Camera trap data showed that grey herons (Ardea cinerea) were the primary predator animal in the system, and that most herons utilized shallow areas in the morning or evening. Increasing the density of stocked salmon brought in more grey herons. More importantly, predation by grey herons resulted in the survival rate of larger salmon being significantly lower than that of the smaller salmon. Our results suggest that it is important to understand local predators, adjust the optimum body size of hatchery fish at release, and choose the appropriate stocking site and time of day for maximizing the effectiveness of fish stocking.

Hatching performance of 35–40 weeks old multi colour broiler breeder normal feathered Nandanam broiler-3, Nacked Neck and Nacked Neck x Nandanam broiler-3 cross was compared. A total of 6813 hatching eggs collected from Nandanam broiler-3, Nacked Neck and Nacked Neck x B3 cross were set for hatching in six consecutive batches. The per cent fertility (P£0.05), total hatchability (P£0.05) and fertile hatchability (P£0.01) were significantly higher for the crosses (77.22±2.17; 64.57±4.09; 83.34±3.06) and Nandanam broiler-3 (73.05±1.52; 55.12±1.42; 75.49±1.66) than Nacked Neck (65.57±3.77; 43.94±5.35; 66.06±4.44). The per cent total embryonic mortality was significantly (P£0.01) lesser in crosses (16.66±3.06) and B3 (24.51±1.66) than Nacked Neck (33.94±4.44). It can be concluded that significantly higher per cent fertility, total hatchability, fertile hatchability and lesser per cent total embryonic mortality were recorded in crosses. Hence, the Nacked Neck x Nandanam broiler-3 cross Na...

An a priori power analysis was conducted to aid the design of experiments aimed at estimating the reproductive success of hatchery-born spawners relative to wild-born spawners using parentage assignment. Power was defined as the probability of rejecting the null hypothesis of equal reproductive contributions of hatchery-and wild-born spawners. A maximum likelihood estimator of relative reproductive success and its variance were derived. The estimator allowed multiple brood years of data, which was an extension of current approaches. Power increased with stock productivity, initial spawner abundance, fraction of recruits and spawners sampled, and the number of brood years examined. Power decreased with error variance used in the production function. Assuming a fixed total number of spawners, power was a concave-down function of the fraction of hatchery-born spawners. Using nominal values of productivity, error variance, and fraction of hatchery-born spawners, an experiment could achieve 0.8 power if it was run for at least 5 years or if it was applied to a stock with high initial female spawners (>200) and run for at least 2 years. Résumé : Une analyse de puissance a priori a servi à planifier des expériences pour estimer, par détermination de la filiation, le succès de reproducteurs provenant de piscicultures par comparaison à des reproducteurs sauvages. La puissance se définit comme la probabilité de rejeter l'hypothèse nulle que les reproducteurs sauvages et ceux des pisciculture contribuent également à la reproduction. Un estimateur de vraisemblance maximale du succès relatif de la reproduction et de sa variance a été mis au point. L'estimateur permet l'utilisation de données provenant de plusieurs années de reproduction, ce qui est une amélioration des méthodes courantes. La puissance augmente avec la productivité du stock, l'abondance initiale des reproducteurs, la fraction des recrues et des reproducteurs échantillonnée et le nombre d'années de reproduction examiné. La puissance diminue avec la variance d'erreur utilisée dans la fonction de production. Si on assume que le nombre total de reproducteurs est constant, la puissance est une fonction concave décroissante de la fraction de reproducteurs provenant des piscicultures. En utilisant des valeurs nominales de productivité, de variance d'erreur et de fraction de reproducteurs nés en pisciculture, une expérience peut atteindre une puissance de 0,8 si elle couvre au moins 5 années ou si elle implique un stock contenant un nombre initial de reproducteurs élevé (>200) sur une période d'au moins 2 ans. [Traduit par la Rédaction] Hinrichsen 872

Fall-run Chinook salmon (Oncorhynchus tshawytscha) from the Sacramento–San Joaquin River system form the backbone of California’s salmon fishery and are heavily subsidized through hatchery production. Identifying temporal trends in the relative contribution of hatchery- versus wild-spawned salmon is vital for assessing the status and resiliency of wild salmon populations. Here, we reconstructed the proportion of hatchery fish on natural spawning grounds in the Feather River, a major tributary to the Sacramento River, using strontium isotope (87Sr/86Sr) ratios of otoliths collected during carcass surveys from 2002 to 2010. Our results show that prior to the 2007–2008 salmon stock collapse, 55%–67% of in-river spawners were of hatchery origin; however, hatchery contributions increased drastically (89%) in 2010 following the collapse. Data from a recent hatchery marking program corroborate our results, showing that hatchery fish continued to dominate (∼90%) in 2011–2012. Though the reb...

Blueback Herring (Alosa aestivalis) populations throughout the East Coast have declined precipitously since the late 1980s and were listed as a Species of Concern in 2006 by the National Oceanic and Atmospheric Administration (NOAA). Natural resource agencies are attempting to restore this species to viable and sustainable levels with fry stockings cultured in hatcheries. To evaluate the long-term contribution of stockings to populations, agencies need an accurate method to track these stocking efforts. Genetic parentage-based tagging is recognized as a feasible means of assessing hatchery contribution of stocked fish to rivers of interest. However, Blueback Herring lack a reliable set of genetic markers to conduct parentage-based tagging (PBT). To this end, we analyzed previously described microsatellites as well as new microsatellite markers identified through NextGeneration sequencing to create a suite of 14 Blueback Herring markers useful for PBT. The markers were successful in parentage analysis for Blueback Herring collected from the Chowan River, North Carolina. An additional challenge in the management of Blueback Herring is the ability to phenotypically distinguish Blueback Herring and the closely related Alewife (Alosa pseudoharengus). Furthermore, recent studies provide evidence that these two species, collectively referred to as river herring, may be hybridizing with one another in some systems. Microsatellite marker AsaC334, developed by Julian and Bartron (2007), can be utilized to discriminate between the two species, as well as to identify their F1 hybrids, thereby providing another genetic tool for hatchery management.

The study is a pioneering effort for sea turtle research and conservation in Karwar, Karnataka, India. I conducted this study as part of my Masters dissertation in Marine Biology between the years 2000 and 2002.The nesting species found through our field survey was the olive ridley turtle.Our first sighting was during a night survey along the Devbag beach of Karwar, and a clutch of 64 eggs was found laid by the turtle near the ipomea-pes-caprae. From a conservation perspective-as these are consumed by the local community- the 64 eggs, and several other clutches salvaged from the fish market, were relocated into a hatchery on the Devbag beach. Low hatching rates from these clutches resulted in the investigation of environmental factors that influenced the hatching success.The environmental variables included
temperature(soil), nest depth, moisture, and sand type.

The hatchlings that emerged from the clutches were also reared for three months both from a research and conservation perspective. Feeding patterns, behavior towards light during release, and other parameters (not detailed in the paper) were recorded in this study.

To date there have been just few studies of sea turtles along Karnataka's coast, and this has been an important study. Although the paper could not afford detailed acknowledgements due to limits prescribed for text size, I would like to acknowledge a few names here: Mr.B.K Dikshit-District Forest Officer of Karwar, and RFO, Mr.D 'Souza, who I sought permission for work on turtles (the permission was granted despite the fact  they had no evidence if sea turtles visited Karwar coast). Eventually as I submitted proof of sea turtle eggs on sale in the Karwar market, and the nesting turtle on Devbag beach, they joined in the effort enthusiastically, by offering facilities such as a hatchery for relocation of turtle nests, and a steel tank to raise hatchlings. There were also other staff who were extremely helpful with my work ; Dr.Rajgopalan, a sea turtle researcher himself,and Senior Scientist from the Central Marine Fisheries, in 2003, allowed me the privilege of being a resource person, and presenting my work during the GOI-UNDP-WII-CMFRI organized turtle workshop in Cochin, happening after a gap of 20 years, since the last held in the 1980's. After my presentation in the workshop, Dr. Kartik Shanker who was a participant and resource person, invited me to share this work in his publication- Kachhappa. Dr. Shanker took much pains to review the report, and got it to good shape, the form you are now reading :).

This study was a major beginning in my turtle story, and the support and nurturing efforts provided by these wonderful people have come a long way in sustaining my turtle career until today.

Initial research work focused on the markets for giant clam products and research on this subject continued throughout the life of the project, with the initial geographical focus widening with the passage of time to include selected islands in the South Pacific, Indonesia as well as other Asian-Pacific countries. In mid-1989 marine property rights in the South Pacific was phased in and the bulk of this work was completed by April 1991. Investigation of production economics commenced in August 1989 and continued throughout the remaining life of the project. Hatchery/nursery economics was considered first followed by the economics of ocean growout. This sequence allowed time for production data to accumulate sufficiently to provide a basis for economic analysis. The research phase involving studies of the economic development possibilities in the South Pacific based on giant clam culture got under way in 1991 and continued throughout most of the remaining life of this project. Because of the broad development and sustainability issues involved, this part of the study was phased in the second part of the schedule for the project.

The valorization of eggshell waste as bio-calcium oxide is crucial for pollution prevention and supporting sustainable development. There are several reports on the thermal conversion of eggshell waste to calcium oxide for the partial or complete substitution of natural lime applications. However, this paper reports the thermal decomposition of large amounts of hatchery eggshell waste on an industrial-scale car bottom furnace for the first time. The hatchery eggshell waste was sundried and placed into five stacked trays in the car bottom furnace. The calcination of the eggshell waste was conducted at 900°C for 3 and 4 h under an atmosphere of air. Both the physical and chemical properties of the eggshell samples and the bio-quicklime products were carefully examined by TGA, SEM, XRD, FTIR, and XRF. The results demonstrate that the purity of calcium oxide in the quicklime products increased from 79% to 87% upon increasing the calcination time from 3 to 4 h. However, the color of the calcined eggshell samples at the surface of the pile was white while the color of the product beneath the surface was black or dark gray. The purity of the calcium oxide of both the black and white calcined samples was 76.4% and 91.5%, respectively. These results indicate the limited efficacy of the car bottom furnace for thermal decomposition of the large amount of eggshell waste to calcium oxide. Additionally, the production cost of bio-calcium oxide is approximately twice the cost of industrial grade lime. For further industrial applications, the furnace should contain the mixing equipment for improving the thermal decomposition of the large pile of eggshell waste. Furthermore, the oil burner system may be used in order to reduce fuel costs.