Although differences between selective pressures in hatcheries and streams have been theorized to cause genetic divergence between hatchery and wild salmonids, evidence of this is lacking. This study was initiated to document the presence or absence of genetic change in hatchery and wild stocks by characterizing genetic traits in fish of various life history stages within a single generation. Nine biochemical traits (enzyme loci) and 12 meristic traits were characterized for adult fall chinook and one or more juvenile stages of their progeny of the 1984 brood year. Study groups consisted of hatchery-reared and naturally-reared subunits of populations in two tributaries of the lower Columbia River: Abernathy Creek and the Lewis River. Parents of both groups from Abernathy Creek were primarily of hatchery origin, whereas parents of both groups from the Lewis River were primarily of wild origin. The experimental design thus included reciprocal comparisons of hatchery and wild-reared groups from each of two stocks: one that has been propagated under hatchery conditions for at least five generations and one that has evolved in a stream environment. Both biochemical and meristic traits varied among adult and juvenile stages within hatchery and wild groups. Changes in some of these traits appear to have been caused by natural selection. This was true even for Abernathy hatchery and Lewis wild groups, which have been in the same environment for many generations. The direction and/or degree of change in some biochemical and meristic traits differed between hatchery and wild groups from a given stream, suggesting that selective pressures of the hatchery and wild environments differed in those cases. However, it could not be determined from these data whether the observed divergence of traits reflects general differences in hatchery and stream environments, or if it reflects population-specific responses to site-specific environmental conditions. The extent to which patterns of genetic change within a single generation might vary among year classes or generations is likewise unknown. Evidence of temporal changes in biochemical and meristic traits of hatchery and wild fish within a single generation has important implications regarding the use of those traits to characterize stocks. Assumptions of temporal stability of biochemical or meristic traits within or between year classes should be applied with caution. Sampling strategies of studies involving these characters should account for the possibility of temporal heterogeneity. Finally, these results suggest that workers using allozymes as genetic tags should test the assumption of selective neutrality of the particular allozyme markers being used. / Graduation date: 1991

Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging hatchery fry influence the emigration, realized densities, growth, habitat use, social structure, and activity patterns of localized populations of wild steelhead fry when the hatchery fry have a competitive advantage conferred by larger size and prior residence. During 1986 and 1987, the above variables were observed daily among hatchery and wild steelhead fry in laboratory stream channels for 8 weeks following emergence in June. The habitat use and social activities for fry of both origins were observed weekly in natural stream reaches from June through August in 1987 to corroborate lab findings. In lab channels, both hatchery and wild fry received 2 treatments: living alone (allopatry) and living together (sympatry). In the lab, fry of hatchery origin emerged 7 to 10 d prior to wild fry and remained larger in size during the 8 weeks of study both years. In natural stream reaches, fry of each origin were observed only in allopatric situations. Wild fry in the field emerged from natural redds while hatchery fry were released in stream reaches as unfed, newly emerged (swim-up) fry. Hatchery and wild fry in lab sections were found to be very similar in their emigration rates, distances to nearest neighbor, growth rates, and use of habitat. Both fry types, regardless of treatment or environment (lab or field), established similar stable social structure and used the same types of aggressive acts. Among all lab groups, once a fry became dominant, it retained that social status to the end of the study period. Significant differences (P<.05 both years) among comparison tests were: 1) in allopatric lab sections, wild fry maintained larger densities than hatchery fry, 2) in sympatry, hatchery fry had a greater tendency to establish stable focal points and social hierarchies more readily, defend larger areas, have better condition, prefer pools with overhead cover more frequently, be more aggressive, and reach stable densities more quickly than the wild fry, 3) fewer hatchery fry in sympatry maintained nomadic positions than wild fry in both treatments, 4) in sympatry, hatchery fry directed more acts of overt aggression toward wild fry than other hatchery fry, 5) wild fry in sympatry usually used defensive or less offensive acts of aggression when interacting with other fry, 6) fry of both origins in natural stream reaches maintained greater distances to their nearest neighbor than fry in allopatric lab sections, 7) dominant hatchery fry in both treatments maintained larger focal areas than subdominant fry, 8) hatchery fry maintained longer lengths than wild fry through the duration of the study, and 9) hatchery fry were more aggressive in sympatry than in allopatry. Potential differences (P<.05 in one year and P<.1 in the other year) were: 1) wild fry in sympatry had lower realized densities, maintained smaller focal areas, had greater proportions of nomadic individuals, and established stable social hierarchies slower than wild fry in allopatric lab sections, 2) wild fry in sympatry had poorer condition than all other fry groups in lab sections, 3) in sympatry, wild fry were the recipients of the majority of aggressive acts perpetrated by hatchery fry and other wild fry and usually assumed the subordinate positions within the social hierarchy, 4) all fry in the lab showed a high preference for pools with overhead cover and low preference for gravel and fines and run areas, and 5) wild fry in allopatric lab sections were more socially active than hatchery fry while the reverse was observed in the natural streams. Any influences that could be attributed to inherent differences between stock origins were probably masked by size differences between fry types. The study would have been more complete had I included sympatric lab sections where wild fry emerged first and where fry types emerged simultaneously, and sympatric reaches in natural streams. Results were further confounded by the limited number of wild adults used for broodstock in the lab segment of this study. Progeny produced from so few adults (5 adults of each sex each year) would have very limited genotypic variation compared to what occurs in natural streams. This may partially explain why some findings from lab sections and natural stream reaches differed. Likewise, genotypic expression among wild fry in lab sections may have varied greatly between years. This could explain differences found between years in behavior of wild fry in similar lab treatments. Although this study does not simulate all possible scenarios, results support suspicions that introductions of hatchery fry of larger size and earlier emergence into streams containing wild stocks could disrupt the social structure and negatively influence the realized densities, spatial distribution, growth, and behavior of wild juveniles in recipient streams. / Graduation date: 1991

Post-release survival of hatchery fishes is imperative to the success of any supplemental stocking program. The purpose of this research was to identify differences between hatchery and wild red drum (Sciaenops ocellatus) and determine if pre-release exposure techniques improve survival of hatchery individuals. Objectives were to contrast survival skills of hatchery and wild red drum from different locations, and examine if exposure to natural stimuli (e.g., habitat, predators, live prey) enhances survival skills in naïve hatchery red drum. Laboratory trials using high-speed videography (250 frames per second, fps) and field mesocosm experiments were used to investigate differences in prey-capture (e.g., attack distance, mean attack velocity, capture time, maximum gape, time to maximum gape, gape cycle duration, and foraging behaviors) and anti-predator performance (e.g., reaction distance, response distance, maximum velocity, time to maximum velocity, mean acceleration, and maximum acceleration) of hatchery and wild red drum. Results indicated that anti-predator performance measures differed significantly between hatchery and wild red drum. Variability in prey-capture and anti-predator performance for hatchery and wild red drum was high (CV range: 5.6 – 76.5%), and was greatest for hatchery fish for the majority of performance variables tested. Exposure to habitat (Spartina alterniflora marsh) did not appear to afford any obvious survival benefits to hatchery red drum, although survival skills did vary according to ontogenetic stage. Hatchery red drum exposed to natural predators (pinfish, Lagodon rhomboides) exhibited significantly greater attack distances during feeding events, and anti-predator performance variables were 20 – 300% in these individuals versus naïve red drum. In predation experiments with free-ranging pinfish predators, mortality rates (Z) ranged from 0.047 – 0.060 h-1 · predator-1; however no significant differences in mortality were found between fish reared with and without predators. Hatchery red drum reared on live prey (Artemia franciscana, mysid shrimp) demonstrated enhanced prey-capture and foraging behaviors as well as anti-predator performance relative to fish reared on artificial (pellet) diets. Findings of this research indicate that several behavioral patterns differed between hatchery and wild red drum; however, these differences can be mediated through the use of various pre-release exposure techniques.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 59-61). Also available via the Internet.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Resumo: Avaliou-se o efeito da temperatura da água no cultivo de larvas de Macrobrachium amazonicum. O delineamento experimental foi inteiramente casualizado, com quatro tratamentos (temperaturas) e quatro repetições. Foram realizados dois experimentos. No primeiro, a temperatura foi avaliada em um amplo espectro (20, 25, 30 e 35°C). No segundo, os tratamentos testados foram 26, 28, 30 e 32°C, definidos de acordo com os melhores resultados obtidos no experimento 1. Cada experimento foi desenvolvido em 16 tanques de larvicultura de 63 L contendo água na salinidade 12 e providos de filtro biológico, aeração e aquecimento controlado por termostatos digitais. A densidade de estocagem foi de 100 e 85 larvas/L nos experimentos 1 e 2, respectivamente. O desenvolvimento larval foi mais lento no cultivo em 20°C, seguido pelos cultivos em 25 e 26°C. Nessas temperaturas, a metamorfose não ocorreu ou foi inexpressiva no tempo de cultivo adotado (17 dias). A temperatura de 35°C apresentou mortalidade total das larvas no 13º dia de cultivo. Conclui-se que a larvicultura de M. amazonicum pode ser realizada em temperaturas que variam de 25 a 32°C. Porém, o cultivo em 30°C apresentou os melhores resultados, maximizando a produção de pós-larvas e minimizando o tempo de cultivo / Abstract: We evaluated the effect of water temperature in the culture of larvae of Macrobrachium amazonicum. The experimental design was completely randomized with four treatments (temperatures) and four replications. Two experiments were conducted. At first, the temperature was evaluated in a broad spectrum (20, 25, 30 and 35°C). In the second, the treatments were 26, 28, 30 and 32°C, defined in accordance with best results obtained in Experiment 1. Each experiment was carried out in 16 hatchery tanks containing 63 L of water salinity at 12 and with a biological filter, aeration and heating controlled by digital thermostats. Stocking density was 100 and 85 larvae/L in experiments 1 and 2, respectively. Larval development was slower in culture at 20°C, followed by cultivation at 25 and 26 ° C. At these temperatures, the transformation did not occur or was negligible in the time of culture adopted (17 days). The temperature of 35°C showed a total mortality of larvae on day 13 of culture. It is concluded that the hatchery M. amazonicum can be performed at temperatures ranging from 25 to 32°C. However, culture at 30°C showed the best results, maximizing the production of post-larvae and minimizing the time of culture / Orientador: Wagner Cotroni Valenti / Coorientador: Alessandra da Silva Augusto / Banca: Cristiana Ramalho Maciel / Banca: Douglas Chodi Masui / Mestre

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / This study aimed to evaluate the effect of the supply of microalgae Chaetoceros muelleri and Thalassiosira fluviatilis on growth, survival and larval development time of the sea cucumber Holothuria grisea. Holothuria grisea larvae were obtained from a spawning induced by heat shock and were cultured in incubators conical cylinder with volume of 15 L, kept in a density of 0,5 larvae/ml and constant aeration. The temperature, pH, dissolved oxygen and water salinity were measured daily and total ammonia analysis (NH3 / NH4+) and nitrite (NO2-) were done on days 05, 09 and 14 after fertilization. Four treatments were tested with five replicates each: a diet with 100% Chaetoceros muelleri; a diet with 100% Thalassiosira fluviatilis; a combined diet containing 50% Chaetoceros muelleri and 50% Thalassiosira fluviatilis (mixed diet); and control (unfed). The feed rate ranged from 20.000 the 40.000 cells/ml for different stages of development. The length of the larvae (&#956;m) was observed on days 2, 8 and 14 after fertilization and survival (%) on days 4, 10 and 14 after fertilization. The larval development time was followed for all treatments. There was no significant difference in temperature, pH, dissolved oxygen and salinity, to the different treatments tested. The best treatments in terms of water quality were Chaetoceros muelleri and Control, with the lowest concentrations of total ammonia and nitrite. The highest concentrations of ammonia and nitrite were found in treatments where the microalgae Thalassiosira fluviatilis was present. The survival rate for all treatments decreased over larval development being quite sharp. The best treatment, when considering the larval development time and total length (&#956;m), was Chaetoceros muelleri. Holothuria grisea completed it larval development time in 17 days after fertilization when fed Chaetoceros muelleri, having indirect development with larval stages of auricularia, doliolaria and pentacula until the arrival of the juvenile stage. / A presente pesquisa teve como objetivos avaliar o efeito da oferta das microalgas Chaetoceros muelleri e Thalassiosira fluviatilis sobre o crescimento, a sobrevivÃncia e o tempo de desenvolvimento larval do pepino do mar Holothuria grisea. As larvas de Holothuria grisea foram obtidas a partir de uma desova induzida por choque tÃrmico e foram cultivadas em incubadoras cilindro cÃnicas, com volume Ãtil de 15 L, mantidas sob uma densidade de 0,5 larvas/mL e aeraÃÃo constante. A temperatura, o pH, o oxigÃnio dissolvido e a salinidade da Ãgua foram mensurados diariamente e anÃlises de amÃnia total (NH3/NH4+) e nitrito (NO2-) foram feitas nos dias 05, 09 e 14 apÃs a fertilizaÃÃo. Foram testados quatro tratamentos com cinco repetiÃÃes cada: uma dieta com 100% de Chaetoceros muelleri; uma dieta com 100% de Thalassiosira fluviatilis; uma dieta combinada contendo 50% de Chaetoceros muelleri e 50% de Thalassiosira fluviatilis (dieta mista); e o controle (sem alimentaÃÃo). A taxa de alimentaÃÃo variou de 20.000 a 40.000 cÃlulas/mL para os diferentes estÃgios de desenvolvimento. O comprimento das larvas (&#956;m) foi verificado nos dias 2, 8 e 14 apÃs a fertilizaÃÃo e a sobrevivÃncia (%) nos dias 4, 10 e 14 apÃs a fertilizaÃÃo. O tempo de desenvolvimento larval foi acompanhado para todos os tratamentos testados. NÃo houve diferenÃa significativa nos valores de temperatura, pH, oxigÃnio dissolvido e salinidade, para os diferentes tratamentos testados. Os melhores tratamentos em termos de qualidade da Ãgua foram Chaetoceros muelleri e Controle, apresentando as menores concentraÃÃes de amÃnia total e nitrito. Maiores concentraÃÃes de amÃnia e nitrito foram verificadas nos tratamentos em que a microlaga Thalassiosira fluviatilis estava presente. A taxa de sobrevivÃncia para todos os tratamentos testados diminuiu ao longo do desenvolvimento das larvas sendo bastante acentuada. O melhor tratamento, quando considerado o tempo de desenvolvimento larval e o comprimento total (&#956;m), foi Chaetoceros muelleri. Holothuria grisea completou o seu tempo de desenvolvimento larval em 17 dias apÃs a fertilizaÃÃo quando alimentadas com Chaetoceros muelleri, tendo desenvolvimento indireto com fases larvais de auriculÃria, doliolÃria e pentÃcula atà a chegada da fase juvenil.

The objectives of the study were to determine whether or not behaviour could be used to predict spawning in Amphiprion akallopisos, and to document the behaviour of this species under various environmental conditions in captivity. The spawning behaviour of A. akallopisos was studied and quantified. Three behaviour patterns - belly touching, nest cleaning by the female and mutual nest cleaning (by the male and the female) were identified as predictors for spawning. The reproductive behaviour of A.akallopisos under three photoperiods was investigated. The photoperiods were: 14L:10D, 10hr15minL:13hr45minD and a natural photoperiod cycle condensed into three months. A. akallopisos maintained under 14 L:10D exhibited a significantly higher frequency and duration of chasing, nest cleaning and total interaction compared to fish kept under 10hr15minL:13hr45minD. A photoperiod of 14L:10D was selected for further studies. As manipulation of photoperiod did not induce spawning, GnRHa was administered to the fish in the diet at levels of 10, 20, 40 and 80 μg/kg BW. Control groups were fed untreated food. None of the dosages were successful in inducing spawning, or spawning behaviour in A. akallopisos. It is possible that the method of hormone application was not suitable for this species. It is also possible that behaviour may regulate blood hormone levels as opposed to endocrine status influencing behaviour. In the third trial, A. akallopisos was maintained with, and without sea anemones in order to determine whether or not anemone hosts are necessary for spawning. The presence of anemones did not induce spawning and A. akallopisos kept without anemones exhibited significantly more interactive behaviour than fish kept with hosts. Spawning of A. akallopisos at a later date without anemones suggests that anemones are not necessary for spawning in A. akallopisos. Light intensity was investigated as a cue for spawning. The reproductive behaviour of A. akallopisos was then studied under light intensities of 4.16 x 10¹⁵ quanta.sec⁻¹.cm⁻², 8.85 x 10¹⁵ quanta.sec⁻¹.cm⁻² and this intensity plus natural light. Spawning occurred mainly under 8.85 x 10¹⁵ quanta.sec⁻¹.cm⁻². Fish maintained under this light intensity exhibited significantly more of nest cleaning behaviour in terms of frequency and duration than fish maintained under low light intensity. A minimum light intensity of 8.85 x 10¹⁵ quanta. sec⁻¹.cm⁻² is recommended for conditioning of this species. This study can be of practical relevance to hatchery managers who can use the methods developed and record predictors for spawning in A. akallopisos and other Amphiprion species. In this way imminence of spawning may be estimated. Most importantly, the study also has academic merit as little work has been undertaken in this field. Although the observational method used in this study was adequate for the purposes of the investigation, future work of this nature should incorporate other methods of documenting gonadal development such as gonadal staging and GSI in order to obtain more conclusive results.

This problem was undertaken to determine a suitable combination of fertilizers that would increase the food in a lake, resulting in increased yield of bass and crappie.

Due to the increasing need to provide refugia for freshwater mussels impacted by anthropogenic activities and exotic species, facilities should be identified and protocols developed for holding mussels in captivity. White Sulphur Springs National Fish Hatchery (WSSNFH), White Sulphur Springs, WV, has held freshwater mussels for nearly eight years, and has the potential to become an important refugium and propagation facility for conservation of mussels in the Ohio River Basin and elsewhere. The goal of this study was to determine the feasibility of holding adult freshwater mussels in long-term captivity at WSSNFH by evaluating survival, energy reserves, and gametogenesis of captive mussels in a recirculating pond system. I relocated three mussel species in the summer of 2001 and 10 mussel species in the summer of 2002 to a recirculating pond system (reservoir and raceway) at the hatchery. Water quality parameters of pH, alkalinity, hardness, temperature, and dissolved oxygen; and algal concentrations were measured periodically from summer 2001 to summer 2003. Annual survival rates of 10 species were estimated (August 2002 to August 2003) using the program MARK. Glycogen, protein, and lipid concentrations in mantle tissue of three captive species (Actinonaias ligamentina, Cyclonaias tuberculata, and Tritogonia verrucosa) were compared to those of wild mussels in the New River. Gametogenic activity and synchrony in A. ligamentina and C. tuberculata were compared between captive and wild mussels. Water quality parameters, with the exception of temperature, were within desirable ranges for most of the study. Temperatures of > 28° C were observed for several days during summers 2002 and 2003. Algal concentrations averaged 1903 cells ml-1 in the raceway (range: 300 to 4658 cells ml-1), which is comparable to algal concentrations reported for nearby rivers. The overall survival rate for 10 freshwater mussel species held in the raceway for one year was 77%. Villosa vanuxemensis had the highest survival rate (96%), and Lampsilis cardium had the lowest survival rate (31%). Although there were fluctuations in glycogen, protein, and lipid levels over 2 yr, there were no overall differences in energy substrates between captive and wild mussels at the end of the study. Captivity did not appear to have a negative affect on gametogenesis. Captive C. tuberculata spawned within the expected time frame between January and June, but slightly earlier than their wild counterparts in the New River. Due to the infestation of the gonads of both captive and wild A. ligamentina by digenean trematodes, little gametogenesis was observed. However, captive holding did not appear to have an effect on trematode infestation rates. From these results, I conclude that captive holding conditions in the recirculating pond system at WSSNFH were adequate for long-term holding of a wide range of mussel taxa. I recommend that WSSNFH continue to be used as an adult holding facility. Further research should be conducted to determine food and habitat preferences of freshwater mussel species in captivity so that optimal holding conditions can be provided for each species. / Master of Science