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Maurolicus stehamanni é a espécie pelágica mais abundante no ecossistema de Quebra de Plataforma da Região Sudeste e Sul do Brasil, sendo o principal componente da dieta dos atuns e das lulas. Com base em amostras coletadas com o N/Oc Atlântico Sul em três épocas do ano distintas, neste estudo foi comparado o crescimento da espécie em duas diferentes localidades, Cabo Frio (RJ) na região Sudeste, e Rio Grande (RS) na região Sul, utilizando a microestrutura, a morfologia e a ontogenia dos otólitos saggitae. Foram analisadas as variáveis: Comprimento padrão, Peso, Sexo, Raio do Otólito, Tamanho do Rostrum, a Espessura de 15 microincrementos consecutivos, Área e Perímetro da linha dos otólitos e a Idade dos peixes obtida por meio da contagem dos microincrementos. Os dados foram analisados por meio de métodos gráficos, análises de variância (ANOVA) e covariância (ANCOVA). As relações entre as variáveis foram modeladas, utilizando-se modelos lineares e não lineares, e comparadas entre as duas regiões. Ficou demonstrada a existência de variações significativas no crescimento entre os indivíduos dessas Regiões. Os peixes da Região Sudeste são maiores, em tamanho e massa e mais velhos, apresentando espessuras dos microincrementos significativamente maiores do que os da Região Sul, fatos que indicam uma maior taxa de crescimento dos peixes na Região Sudeste. Os peixes do Sudeste apresentam, em média, para uma mesma idade, menor Raio, Área e Perímetro dos otólitos, fato atribuído a um efeito da taxa de crescimento, como constatado para outras espécies do gênero. Um novo método gráfico foi elaborado para representar as mudanças ontogenéticas que ocorrem no formato dos otólitos ao longo do crescimento, utilizando-se sua silhueta e os índices de forma: Circulariedade e o Fator de Forma, os quais foram comparados entre Regiões. Apesar das diferenças citadas, semelhanças foram detectadas entre as regiões, para os parâmetros do modelo de von Bertalanffy do Sudeste (L= 48,04 mm e k= 0,01 dias -1) e do Sul (L =46, 12 mm e k= 0,01 dias -1) e, no formato dos otólitos. Hipóteses sobre as tais diferenças e semelhanças foram levantadas e discutidas. / Maurolicus stehamanni is the most abundant pelagic fish in the Slope Ecosystem of the South and Southeastern Brazil Region, being the main component of the diet of tunas and squids. Based on samples collected with the R.V. Atlantico Sul in three distinct seasons of the year, the main objective of this study was to compare the growth of the species between two different localities, Cabo Frio (RJ) in the Southeastern Region, and the Rio Grande (RS) in the South, through the analysis of the microstructure, morphology and ontogeny of otoliths. The following variables were evaluated: Standard Length, Weight, Sex, Otolith length, Size of the Rostrum, Width of 15 Consecutive Microincrements, Area, Perimeter of the otolith contour line and Age. Data were analyzed through graphical methods, analyses of variance (ANOVA) and covariance (ANCOVA). The relationships between the variables were modeled, using linear and non linear models, which were compared between the regions. It was found significant variations in growth between regions. Fish from the Southeast Region were bigger, in size and mass, and older, presenting microincrements width significantly larger than of the South region, indicating a higher growth rate of the specimens from the Southeast region. The fish from Southeast region presented on average, at a same age, smaller Lenght, Area and Perimeter of the otoliths, which can be attributed to a growth rate effect, as verified in other species of the genera. A novel graphic approach was performed in order to represent the ontogenetic changes in the shape of the otoliths during the growth, using its silhouette and indices of form, Circularity and the Form Factor. Despite of those differences, similarities were detected between the fish from the two regions for the parameters of the von Bertalanffy´s model, Southeast (L= 48,04 mm and k = 0,01 days-1) and South ( L = 46.12 mm and k = 0,01 days-1), and for the otolith´s shape. Hypotheses about variations and similarities were raised and discussed.

Bull trout are a fish species listed as threatened under the Endangered Species Act.Historically, they ranged from Northern California at the southernmost extent, into Canada at the northern most extent, and east into Nevada and Montana. Bull trout are highly migratory and require large, unfragmented habitats to persist and are thus highly susceptible to human induced land-use practices. The goal of my thesis was to obtain a better understanding of bull trout movement patterns in the Walla Walla River, Washington using complimentary techniques; Passive Integrated Transponder (PIT)technology and otolith microchemistry. PIT tags can be injected into a fish body cavity, similar to how pets are “chipped”, and as the fish swim through antennas placed in the river, their location and movements are be documented.Otolith microchemistry is a technique that is similar to analysis of tree rings. The otolith, a hard bony structure of a fish’s ear, develops over a lifetime and as the rings of the otolith are created the chemical signature in the water in which they live is recorded and can be compared to chemical makeup of water samples collected through the river system. Using these two techniques, I found that the age or size of a fish and the season are important factors to explain both a fish’s movements and where in the river a fish might be located at a given time. Knowing at what size, age and season a fish is attempting to migrate allows managers to provide the best possible river conditions (e.g., temperatures, flow) to allow for unimpeded migrations to occur and to foster conservation and recovery of bull trout populations.

The Deepwater Horizon blowout occurred on April 20th, 2010 and released nearly 5 million barrels of crude oil into the northern Gulf of Mexico causing pollution of the water and sediment inhabited by many fishes for at least 87 days while the wellhead went uncapped. Populations of the Gulf of Mexico Red snapper, Lutjanus campechanus, an important fish to the ecology and economy in the region, exhibit affinity to shallow water oil infrastructure such as the Deepwater Horizon making them especially vulnerable to crude oil contamination. The objective of this study is to determine growth of Red snapper before, during and after the DWH spill and to assess factors potentially explaining such growth variation. Sagittal otoliths were collected from individuals sampled in 2011 - 2013 from scientific, demersal long-line surveys in the northern Gulf of Mexico (GoM) and West Florida Shelf (WFS). Age and otolith increment width analyses were performed. No annual variation in von Bertalanffy growth parameters was determined among the three catch years. The L∞ , K and t0 estimated from the complete data set (2011-2013) were 82.91, 0.20 and 0.43, respectively. However, significant differences in otolith increment width-at-age were observed in increment numbers three - seven in years following the DWH event, with declines of 13%, 15% and 22% occurring in the fourth -sixth increments. To asses the potential significance of exogenous environmental variables to observed yearly growth variation I evaluated five parameters - meridional (V) winds, zonal (U) winds, wind stress curl which is a measure of upwelling, Mississippi River discharge, and mean sea level anomaly - using a linear mixed effects model. Hypothesis testing via reduced maximum likelihood estimates indicated that variation in U winds and River discharge could significantly explain the variation in increment width. However, further work must be done in order to determine the natural, inter-annual variability in age specific growth before the results from model fitting can be considered conclusive. Mean back-calculated weight-at-age measurements were obtained in order to assess potential variation in productivity changes. Results from forward difference and reverse helmert contrast-coding indicated that weight at age three+, four+ and five+ declined by 16%, 15% and 11% in 2010, respectively. These analyses indicate a significant decline in fish growth in 2010 coincident with the DWH event, followed by a return to pre-spill rates.

The koi carp Cyprinus carpio is an invasive fish that has reached high numbers and biomass in the North Island of New Zealand, particularly in the Waikato region. This species has a variety of negative effects on aquatic ecosystems, increasing turbidity, uprooting aquatic macrophytes, and affecting water column nutrient levels. Recent research in Australia and New Zealand has shown that adult carp, though largely restricted to small scale movements, are capable of moving long distances. Movement in adult carp may be underestimated by these studies, and comparatively little is known about the movement of smaller carp. This study examined the feasibility of using laser ablation otolith microchemistry to track koi carp movement and identify spawning areas. Water samples from six locations (Lake Waahi, Lake Whangape, Lake Waikare, the Whangamarino River, and the Waikato River at Aka Aka and Rangiriri) were analysed using inductively coupled plasma mass spectrometry (ICP-MS). Significant differences between sites were found in the water concentrations of many elements. Koi carp were collected from the above locations, as well as from Opuatia Stream, Pungarehu Stream, the Maramarua River and Lake Hakanoa. The elemental concentrations in the asteriscus otoliths were analysed using laser ablation inductively coupled plasma mass spectrometry (LA‐ICP-MS). Elemental concentrations in the edges and nuclei of adult koi carp and the edges of young-of-the-year (YOY) koi carp were significantly different between capture sites. No significant differences were found in elemental concentrations between sites in the nuclei of YOY koi carp. A discriminant function analysis (DFA) was carried out using the otolith edge elemental signatures of koi carp. The model used Ba, Sr, Mg, Rb and Zn concentrations to differentiate between four capture locations: the Waikato River, Pungarehu Stream, Lake Waahi, and Lake Waikare and Pungarehu Stream. The DFA was able to correctly predict the capture location of 82% of koi carp using their otolith edge elemental signatures. The classification functions created using koi carp otolith edge signatures were then used as a training set to classify otolith nucleus signatures. The otolith nuclei of 80% of YOY koi carp were classified to their site of capture, suggesting they had not moved between locations. The majority of adult koi carp caught at Lake Waikare, Whangamarino River, Pungarehu Stream and Opuatia Stream had nucleus signatures matching their capture sites, indicating that these fish originated from their capture location. Koi carp from other sites likely moved there from another location. The majority of adult koi carp (88%) caught at the Waikato River at Rangiriri had otolith nucleus signatures matching Lake Waikare and Pungarehu Stream. Adult koi carp caught at Lake Waahi and the Waikato River at Aka Aka had otolith signatures corresponding to a range of locations. While some areas (Lake Waikare, Pungarehu Stream) appear to have resident koi carp populations that likely originated there, others (Lake Waahi, the Waikato River) appear to have koi carp populations of mixed origin. These results indicate that Lake Waikare, Pungarehu Stream and the Whangamarino River may be important sources of koi carp recruits in the lower Waikato region.

Prenatal alcohol exposure is known to have many profound detrimental effects on human fetal development (fetal alcohol spectrum disorders), which may manifest into lifelong disabilities. Although hearing deficiency is a recognized effect, how alcohol affects the auditory/vestibular systems has not been well studied. This is the first study that used the zebrafish, Danio rerio, as a model organism to investigate morphological effects of alcohol on the developing octavolateral system (auditory, vestibular and lateral line). Zebrafish embryos of two hours post fertilization (hpf) were treated in 2% alcohol for 48 hours and screened at 72 hpf for morphological defects of the inner ear and lateral line neuromasts. Inner ear size and otoliths of zebrafish from both alcohol-treated and control groups were examined using light microscopy. Zebrafish were stained with fluorescent vital dyes to visualize lateral line hair cells using confocal microscopy. The size of neuromasts and length of kinocilia were measured using scanning electron microscopy. Results reveal that alcohol treatment during the early development impairs the formation of otoliths, neuromasts and their hair cells, as well as ear size and kinocilium length. We observed several otolith phenotypes including zero, one, two abnormal, two normal and multiple otoliths for alcohol-treated zebrafish. Fetal alcohol exposure appears to severely impact the size of both anterior and posterior lateral line neuromasts. Our results indicate that early fetal alcohol exposure most likely results in functional defects of the octavolateral system due to inner ear and lateral line dysmorphology.

¡@Bony flyingfish (Hirundichthys oxycephalus) is the primary component of flyingfish-egg fishery captures in the northeastern waters of Taiwan, and is also one of the dominant species of flyingfish in eastern waters of Taiwan. In recent years, people are conscious of overfishing in negarding to the continuously decreasing flyingfish resources. For rational management and sustainability of the fishery, there is an urgent need to study age and growth of the fish. Based on the laboratory-reared fish from the fertilized eggs collected in the wild, the daily periodicity of growth increments in three pairs of otoliths (lapillus, sagitta and asteriscus) was validated. First growth increment formed in the first day after hatching for sagitta and lupillus, and was in the eleven day after hatching for Asteriscus. ¡@¡@Ages of the wild flyingfish sample of 5.4~229.1 mm FL collected by drifted gillnets in Hualian, Taitung, Lyudao and Lanyu waters during April 2009 to March 2010, were determined by daily growth increment (DGI) counting in asteriscus, as adjusted by an addition of 11 DGIs. The von Bertalanffy growth parameters of the fish were estimated to be 253.9 mm in asymptotic length and 0.00753 mm d-1 in growth coefficient. Use DGIs estimation hatch date from otolith ringing, and estimated spawning date by deduct from 3 day hatch requisition. we found 2 recruitment group in eastern Taiwan within a year, most fish hatched either in summer or winter. In this study showing that bony flyingfish was an grew fast and had long longevity sp., therefore, on fishery management, we should decrease the fishing pressure and give them enough surplus biomass, so the biomass could recover rapidly. And we found two recruitment group, one could behalf of stock from east taiwan, and maybe it could behalf of two stocks ,on the other hand the method of fishery management should be a quite different .We suggest to confirm by the further reproductive biology research.

Years of habitat loss, hatchery production and water regulation in the Puntledge River have potentially compromised diversity in coho salmon. Diversity was interpreted from age and early rearing history of mature coho that returned to spawn in 2009 (n=28). Life history groups were interpreted through a visual analysis of the micro-chemistry profiles in the otoliths. There were 2 age classes and 9 life history groups detected. Group differences in Sr:Ca, Ba:Ca and Mn:Ca were significant (p<0.0001) between groups with >2 members (n=6). Cluster analysis using Sr:Ca and Ba:Ca resulted in similar groups. Sr:Ca profiles indicate different rearing habitats, coho that reared in both freshwater and the estuary, and a Jack that reared entirely in the estuary. Results support the need for further studies on the extent of diversity in Puntledge coho, and management actions that identify, restore and protect important rearing habitats.

Universiẗat, Diss., 2001--München.

Knowledge of habitats used by riverine fishes throughout their life history is important for management and conservation. Naturally occurring chemical markers in otoliths have recently been used to determine natal origins and environmental history of fishes in a variety of marine and freshwater environments. However, to our knowledge no studies have examined the applicability of this technique in large floodplain rivers in United States. We evaluated otolith microchemistry and stable isotopic composition as tools for determining origins of fishes in the upper and middle Mississippi and lower Illinois Rivers, their tributaries, and associated floodplain lakes. Fishes were collected from 21 sites during summer 2006 and 2 additional sites in spring 2007. Water samples were obtained from the same 23 sites plus three additional sites during summer and fall 2006 and spring 2007. Otoliths and water samples were analyzed for δ18O, and a suite of trace elements; otoliths were also analyzed for δ13C. Tributaries, floodplain lakes, and the Illinois and Mississippi Rivers had distinct isotopic and elemental signatures. Tributaries on the Missouri and Illinois sides of the middle Mississippi River could also be differentiated by their elemental and isotopic fingerprints. Otoliths reflected differences in water chemistry among habitats. Results indicate that otolith microchemistry and stable isotope analyses provide a potentially effective means of determining origins and environmental history of fishes in large river-floodplain systems.