Bonefish (Albula spp.) support an economically important sport fishery, yet little is known regarding the reproductive biology of this genus. Analysis of oocytes histology and sex hormone levels was conducted on wild female bonefish sampled during and outside the spawning season in Grand Bahama, Central Andros, and South Andros, The Bahamas to assess reproductive state. Bonefish are commonly found along shallow water flats, or in pre-spawn aggregations (PSA) during spawning months. 17β-estradiol levels suggest vitellogenic consistency between habitats. However, fish are more reproductively developed at PSA based on the occurrence of larger, more prevalent vitellogenic oocytes and evidence of final maturation. Variability in hormone levels and spawning readiness existed between Grand Bahama and Andros PSAs, suggesting peak spawning may differ by region. Findings from this study will contribute baseline data to the captive bonefish restoration project at Harbor Branch Oceanographic Institute and to the limited ecological data regarding bonefish reproduction. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Relying on field research to complete the life history for certain fish species can be inadequate, but laboratory research can be used to fill these gaps. These gaps exist for Bonefish (Albula spp.), a tropical marine fish and popular sportfish. In this study, aquaculture techniques were applied to Bonefish in a captive setting at Harbor Branch Oceanographic Institute (HBOI) and Cape Eleuthera Institute (CEI) to induce spawning and describe early ontogeny. Photothermal manipulations and hormone injections were used to induce gonad maturation and spawning, which was achieved once at CEI and is the first record of hormone-induced spawning for Bonefish. From that spawn, egg and larval development were recorded and described through 26 hours and 56 hours respectively, representing the first record of these early life stages for Bonefish. This work expands upon what is known about Bonefish reproductive biology and will be useful for management and future captive research. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Orientador: Sergio Ricardo Batlouni / Coorientador: Rafael Yutaka Kuradomi / Banca: Fábio Rosa Sussel / Banca: Laura satiko Okada Nakaghi / Resumo: O principal objetivo deste trabalho foi determinar as concentrações plasmáticas de 17α,20β-dihidroxi-4-pregnen-3-one (DHP), Estradiol 17β (E2), Testosterona (T) e Prostaglandina F2α (PGF2α) e a distribuição percentual dos diferentes tipos de ovócitos presentes nos ovários ao longo do processo de hipofisação de pacu (Piaractus mesopotamicus) com ou sem uso de PGF exógena. Para isto, 23 fêmeas foram distribuídas em cinco tratamentos, com indução dividida em duas doses com intervalo de 24 horas: (0,2 mL.kg-1 solução salina) + (0,2 mL.kg-1 solução salina) (T1); (0,2 mL.kg-1 solução salina) + (0,2 mL.kg-1 solução salina e 2 ml PGF2α) (T2); (0,6 mg.kg-1 EBHC (extrato bruto de hipófise de carpa)) + (0,2 mL.kg-1 solução salina e 2 mL PGF2α) (T3); (0,6 mg.kg-1 EBHC) + (5,4 mg.kg-1 EBHC) (T4); (0,6 mg.kg-1 EBHC) + (5,4 mg.kg-1 EBHC e 2 mL PGF2α) (T5). Foram coletadas amostras de sangue e ovócitos para análise dos níveis plasmáticos de PGF2α, DHP, E2 e T e avaliação dos tipos de ovócitos em quatro períodos após a segunda dose. O uso de PGF2α exógena provocou um pico plasmático de PGF2α uma hora após a segunda dose hormonal. A hipofisação, com ou sem o uso de PGF2α exógena, provocou pico plasmático de PGF2α no momento da desova. O uso de PGF2α exógena juntamente hipofisação (T5) eleva a taxa de ovulação de pacu em relação a fêmeas apenas hipofisadas (T4), provavelmente em função de níveis de GVBD e de PGF2α superiores de T5, quatro horas após a segunda dose hormonal. / Abstract: The main objective of this study was to determine the plasma concentrations of 17α, 20β-dihydroxy-4-pregnen-3-one (DHP), 17β-Estradiol (E2), Testosterone (T) and Prostaglandin F2α (PGF2α) and the different types of oocytes present in the ovaries throughout the pacu (Piaractus mesopotamicus) hypophysation process with or without the use of exogenous PGF2α. To that, 23 females were distributed in five treatments, with induction divided into two doses with a 24-hour interval: (0.2 mL.kg-1 saline) + (0.2 mL.kg-1 saline) (T1); (0.2 mL.kg-1 saline) + (0.2 mL.kg-1 saline and 2 mL PGF2α) (T2); (0.6 mg.kg-1 CPE (crude pituitary extract)) + (0.2 mL.kg-1 saline and 2 mL PGF2α) (T3); (0.6 mg.kg-1 CPE) + (5.4 mg.kg-1 CPE) (T4); (0.6 mg.kg-1 CPE) + (5.4 mg.kg-1 CPE and 2 ml PGF2α) (T5). Blood and oocyte samples were collected for analysis of plasma levels of PGF2α, DHP, E2 and T in four periods after the second dose. The use of exogenous PGF2α caused a plasma peak of PGF2α one hour after the second hormonal dose. Hypophysation, with or without the use of exogenous PGF2α, caused a plasma peak of PGF2α at the time of spawning. The use of exogenous PGF2α together with hypophysation (T5) increased the pacu ovulation rate in relation to hypophysation only (T4), probably as a result of higher GVBD and PGF2α levels of T5, four hours after the second hormonal dose. / Mestre

Orientador: Renata Guimarães Moreira Whitton / Banca: Elizabeth Romagosa / Banca: Rosicleire Veríssimo Silveira / Banca: Taís da Silva Lopes / Banca: Gisele Cristiane de Melo Dias / Resumo: O lambari-do-rabo-amarelo (Astyanax altiparanae) na natureza, reproduz durante a primavera-verão, mas as fêmeas permanecem vitelogênicas ao longo de todo ano, incluindo o período de inverno, quando a desova não ocorre. O presente estudo investigou a influência da modulação da temperatura no eixo hipotálamo-hipófise-gônadas do lambari, fora da estação reprodutiva, bem como os efeitos de diferentes terapias com análogo do hormônio liberador de gonadotrofinas (GnRHa). Foram conduzidos dois experimentos, um com múltiplas injeções de GnRHa e outro com implantes de GnRHa, em duas doses e duas temperaturas da água, sendo uma correspondente ao inverno e outra ao verão. No final do período experimental, as fêmeas das condições experimentais diferentes foram induzidas a desovar utilizando gonadotrofina coriônica humana (hCG). A análise dos dois experimentos em conjunto, demonstra que independente da forma de administração, a suplementação de fêmeas de A. altiparanae com GnRHa fora do período reprodutivo desencadeia alterações no eixo hipófise-gônadas, dependentes da temperatura de exposição, que aumenta a viabilidade na produção de larvas desta espécie. As injeções repetidas desencadearam uma resposta mais evidente na hipófise de animais em baixas temperaturas. Os dados dos índices de desempenho na reprodução induzida mostraram que a administração de GnRHa na forma de injeções também foi mais eficiente na produção de larvas, quando mantidos em temperaturas mais elevadas, enquanto o GnR... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The lambari-do-rabo-amarelo (Astyanax altiparanae) in the wild reproduce during spring and summer, but females remain vitellogenic throughout the year, including the winter period, when spawning does not occur. The present study investigated the influence of temperature modulation on the hypothalamic-pituitary-gonad axis of the lambari in non-breeding season, as well as the effects of different therapies with gonadotropin releasing hormone analog (GnRHa). Two experiments were conducted, one with multiple injections of GnRHa and the other with GnRHa implants, in two doses and two water temperatures, one corresponding to winter and another of summer. At the end of the experimental period, females from different experimental conditions were induced to spawn using human chorionic gonadotrophin (hCG). The analysis of the two experiments shows that regardless of the administration form, the supplementation of GnRHa in A. altiparanae females, in non-breeding period, triggers alterations in the pituitary-gonadal axis, depending on the exposure temperature, increasing the viability in the production of larvae of this species. Repeated injections elicited a more evident response in the pituitary gland at low temperatures. The performance data on induced reproduction showed that the administration of GnRHa in the form of injections was more efficient in larvae production, when kept at higher temperatures, while GnRHa implants resulted in higher estimated larval production at lower tempe... (Complete abstract click electronic access below) / Doutor

The planktonic shrimp Acetes intermedius is an ecologically and commercially important species. Since it was described by Omori(1975) as a new species, there have been relative few studies focused on the reproduction of this species. The aim of this study is to examine the spawning, egg hatching, larval development of A. intermedius and the related environmental factors. The newly released eggs of Acetes intermedius were round, 200 um in diameter in average, transparent, demersal and were usually green in color. The cleavage pattern of developing egg is holoblastic. Larval stages could be divided into four stages: nauplius, protozea, zoea and postlarva. Nauplius, protozoea and zoea can be further divided into 4, 3 and 2 substages, respectively. At water temperature 30 ¢J and salinity 25 psu, hatching of nauplius was around 10-11 h after spawning while protozoea, zoea and postlarva occurred around 29h, 5-6 and 7 days after spawning, respectively. Newly released eggs were introduced directly into different temperature-salinity combinations. The results revealed that eggs failed to hatch at 15¢J at all salinities tested and at salinities 0 to 10 psu at all temperatures examined. Hatching success started to decrease at salinity 15 psu at 30¢J and at 20 psu at both 25¢J and 20¢J. When salinity was not lower than 25 psu, the hatching success reaches nearly 90 % in average and is generally similar among temperatures tested. Hatching started at about 10, 14 and 28h after spawning at temperatures 30, 25, 20¢J, respectively. At salinity 25 psu, hatching time was the shortest at both 25 and 30¢J, whereas it was similar among salinities at 20¢J. Eggs and nauplii I hatched at 30 ¢J, 30 psu were incubated in the different temperature-salinity combinations. It took eggs incubated at salinities ranging from 20 to 35 psu about 28, 45 h and 5 days to develop into protozoea I at 30, 25 and 20 ¢J, respectively. Nauplii usually started to metamorphose earlier at 25 and 30 psu than at 35 and 20 psu at 25 and 30¢J while no significant trend in metamorphosis time was found among different salinities at 20¢J. Nearly 90% of nauplii metamorphosed into protozoea I at 25 and 30¢J while the metamorphosis rate of nauplii was greatly reduced at 20¢J. The metamorphosis rate was usually higher around 20-25 psu and lower at 15 and 35 psu in all temperatures examined. While spawning, the gravid females swam near the water surface and were rapidly beating pleopods. The eggs were directly released into water. Spawning usually took place at night but the timing is generally peaked around midnight. The gravid females spawned in the early spring before midnight while they spawned after midnight in summer. The spawning timing is delayed at low temperature (24¢J) while it is not affected by high temperature (30¢J). The salinity did not show any effects on spawning but the hatching success of eggs released at 15 and 35 psu was significantly lower than those at 20-30 psu. The gravid females were tended to be endogenous timed to spawn in the night since spawning was not affected by absence of presence of light.

The blue crab, Callinectes sapidus, supports a successful fishery in the Atlantic Ocean and throughout the Gulf of Mexico, with a total landing of 8,158,788 lb. and a total value of $10,562,128 for the state of Florida during 2012 (FWC 2012 Annual Landings Summary). An accurate and comprehensive understanding of the blue crab's life history and seasonal migration behavior is essential in defining effective management strategies for the fishery. Tag recapture studies and ultrasonic tracking methods for studying blue crab migrations are costly in terms of time and resources. In this study an alternative approach, microchemical natural tagging, was successfully used to determine a female's mating habitat. This approach assumes that the exoskeleton of the post-terminal molt female blue crab reflects the mating habitat's chemical signature and that the chemical signals are stable over time. To test these hypotheses, mature female blue crabs were collected from two Tampa Bay locations. Collected crabs were placed in tanks for 29 days, a subset was sacrificed at T = 0 and then twice per week, and the exoskeletons were analyzed via Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Elemental Analyzer Infrared Mass Spectrometry (EA-IRMS) to observe the stability of the exoskseletal chemical signature over time. Over the 29 day time series, no significant change in the concentrations of Li, Ca, and Ba, or the isotopic ratios of 13C/12C (δ13C) and 15N/14N (δ15N) were observed (ANOVA p-value > 0.05). A Canonical Analysis of Principal Coordinates (CAP)-based discriminate analysis with leave-one-out cross-validation collectively compared Li concentrations, δ13C, and δ15N among five Tampa Bay locations, producing a confusion matrix successfully classifying field collected crabs into: Alafia River 33%#37;, Little Manatee River 71%#37;, Palm River 67%#37;, Safety Harbor 30%#37;, and Skyway Fishing Pier 83%#37;, with an overall classification success of 66%#37;. These results suggest that the largest biomass component of the migratory pulse collected near the mouth of Tampa Bay was dominated by crabs originating from an area not widely harvested by commercial fishermen, as relatively few of the migrating females were matched to riverine locations that were intensively fished. Instead, most appeared to originate from open waters of Tampa Bay. It is possible that low densities of blue crab inhabiting a large area that is not commercially fished, effectively shields a proportion of the individuals in the Tampa Bay estuary from economic exploitation, creating a density-dependent natural harvest refugium.

Capelin is an important forage fish species in the Northwest Atlantic and the primary prey species of many top predators. Capelin undergo extensive inshore migrations (> 350 km) to coastal spawning grounds in the spring where the timing of inshore arrival is highly variable. I investigated the influence of intrinsic factors and proxies for extrinsic factors on the timing of arrival of capelin at spawning sites on the northeast coast of Newfoundland (2012 and 2013). Despite high inter-annual variation in almost all factors examined, intrinsic factors, specifically length and age, consistently varied with timing of arrival at spawning sites for both males and females, unlike proxies for extrinsic factors. These results are important for the management of this critical fish species, as selective harvesting by the capelin fishery of early-arriving fish may impact the age/size structure of the population, recruitment, and result in increased variability in the timing of spawning.

Capelin (Mallotus villosus) is the key forage fish in the north Atlantic. A short-term anomalous event in Newfoundland waters in the early 1990’s caused many changes to their biology, including excursions into alternate (subtidal) spawning habitats. Subtidal spawning sites have drastically different environmental conditions than the beach sites that they have been using since at least the 1940’s. This thesis examines various aspects of the reproductive biology of capelin to understand the mechanisms underlying the use of two environmentally divergent spawning habitats. Local adaptation in early life history stages was examined by raising artificially fertilized capelin eggs across three temperatures that capelin are likely to encounter at both spawning habitats. At cool to medium temperatures, larvae experienced higher hatching success, were larger at hatching and had more nutritional reserves relative to warm temperature conditions. There was no evidence of local adaptation, providing the first support for a facultative spawning strategy. The influence of global warming temperatures may be buffered through the utilization of either spawning habitat provided it is within this thermal optimum. A comparative analysis of adult body shape and condition between the two habitats provided further evidence that spawning habitat use in a given year is facultative. Patterns in fecundity drastically changed for capelin since it was last examined prior to the 1990’s. In addition to lower average population fecundity, a wide range of fecundities was also observed across all length-classes. I show that the strong relationship between length and fecundity in capelin has broken down in recent years, making easily collected size measurements an inappropriate proxy for the reproductive potential of this fish. Within-female variation in offspring size and developmental duration was higher when compared to among-female variation. This supports diversified bet-hedging in capelin, a strategy that would allow capelin to spawn in thermally available habitats without experiencing reproductive failure in exceedingly warm or cold years. It is likely that high variation in traits allow capelin to utilize alternate spawning habitats, ensuring that at least some larvae survive.

Anadromous Pacific salmon (Oncorhynchus spp.) return annually from marine ecosystems to their natal freshwater habitat to spawn and die. Runs of spawning salmon provide an important source of nutrients and energy to watersheds. However, in coastal systems, substantial amounts of salmon-derived nutrients can be exported back to estuaries. Human land use, including agriculture and urban development, also contribute substantial nutrients to coastal ecosystems, and have the potential to confound results from salmon-derived nutrient studies. This thesis examines the influences of spawning salmon and human land use on stream nutrient and particulate dynamics, including export to estuaries. It also investigates the use of the stable isotope composition (δ13C and δ15N) of estuarine clams, the varnish clam (Nuttalia obscurata: Reeve, 1857) and the manila clam (Tapes philippinarum), and their food sources, as indices of the freshwater export of salmon-derived nutrients to estuaries. Samples were collected from three nearby river-estuary systems along Southeast Vancouver Island, British Columbia. Study systems had either a large number of returning salmon and little human land use (Goldstream), few returning salmon and extensive human land use (Shawnigan), or few returning salmon and little human land use (Holland). In Goldstream River, high abundance of salmon carcasses increased concentrations of total nitrogen and total phosphorus stream water below a barrier to upstream salmon migration. Carcasses also contributed substantial amounts of organic matter to the stream, as indicated by high δ13C and δ15N, and corresponding low C:N ratios in suspended particulate organic matter. My calculations indicate that between 51-77% of the phosphorus transported upstream by migrating salmon, was exported back to the estuary. Human land use also increased downstream nutrient concentrations and raised baseline δ15N in stream ecosystems, which is cause for concern and caution for salmon-derived nutrient studies in land use-affected watersheds, or in the reverse situation, for anthropogenic nutrient studies in watersheds that support runs of anadromous salmon. The high δ15N of anthropogenic nitrogen was not evident in the Shawnigan Estuary. In the Goldstream Estuary salmon-derived nutrients appeared to increase the δ15N of clams, and both the δ13C and δ15N of sedimentary organic matter (SOM), with more enrichment in the high intertidal zone near the river mouth, than in the mid-intertidal zone. The stable isotope composition of clams and SOM was relatively constant across the period of salmon spawning and carcass decay, indicating that they may reflect a legacy salmon-derived nutrient input into estuaries. This study demonstrates that substantial amounts of salmon-derived nutrients are exported back downstream to the Goldstream Estuary where they appear to become integrated into the estuarine food web. Data from a series of estuaries receiving a range of nutrients inputs from salmon is needed to confirm indices of salmon-derived nutrients in estuaries. There is also need for more extensive examination regarding the downstream effects of salmon-derived nutrients in areas such as estuarine productivity, community composition, and positive feedback mechanisms that influence salmon populations. This last area of research is of particular importance considering the high number of salmon stocks at risk in B.C.

Capelin (Mallotus villosus) is the key forage fish in the north Atlantic. A short-term anomalous event in Newfoundland waters in the early 1990’s caused many changes to their biology, including excursions into alternate (subtidal) spawning habitats. Subtidal spawning sites have drastically different environmental conditions than the beach sites that they have been using since at least the 1940’s. This thesis examines various aspects of the reproductive biology of capelin to understand the mechanisms underlying the use of two environmentally divergent spawning habitats. Local adaptation in early life history stages was examined by raising artificially fertilized capelin eggs across three temperatures that capelin are likely to encounter at both spawning habitats. At cool to medium temperatures, larvae experienced higher hatching success, were larger at hatching and had more nutritional reserves relative to warm temperature conditions. There was no evidence of local adaptation, providing the first support for a facultative spawning strategy. The influence of global warming temperatures may be buffered through the utilization of either spawning habitat provided it is within this thermal optimum. A comparative analysis of adult body shape and condition between the two habitats provided further evidence that spawning habitat use in a given year is facultative. Patterns in fecundity drastically changed for capelin since it was last examined prior to the 1990’s. In addition to lower average population fecundity, a wide range of fecundities was also observed across all length-classes. I show that the strong relationship between length and fecundity in capelin has broken down in recent years, making easily collected size measurements an inappropriate proxy for the reproductive potential of this fish. Within-female variation in offspring size and developmental duration was higher when compared to among-female variation. This supports diversified bet-hedging in capelin, a strategy that would allow capelin to spawn in thermally available habitats without experiencing reproductive failure in exceedingly warm or cold years. It is likely that high variation in traits allow capelin to utilize alternate spawning habitats, ensuring that at least some larvae survive.