The response of rainbow trout (Salmo gairdneri) to lures was investigated in trolling experiments at Loon Lake, British Columbia. The "action" of a lure was found to be an important parameter in determining its efficiency: of four actions tested, the flatfish caught the greatest number of fish. Although the color of lure was not significant, red lures were more efficient than yellow, green, and blue, and more efficient than various color patterns of red and white. The presence of a dodger with lures did not affect their efficiency, but larger fish were caught. No size selection occurred with either colors or actions of lures. In laboratory feeding experiments using dyed trout eggs as food, red was selected first or second more often than yellow, green, or blue. The color of background against which the fish were fed, and individual differences among fish caused significant changes in the preference shown for various colors of food. Combining two colors also affected the selection intensity, depending upon the contrast between the two colors. Preferences for different colors of food were not influenced by the hunger level of the fish, measured in terms of the quantity of food in the fish's gut. In the course of the experiments it was incidentally observed: (1) that rainbow trout possess a striking ability to match the hue of their skin (mainly in the dorsal region) to that of the background in which they are kept; (Z) the color of background affects the activity level of rainbow trout: yellow produces the highest level of activity and green the lowest. / Science, Faculty of / Zoology, Department of / Graduate

Sleep is a complex behavioral state with ramifications on multiple levels of homeostasis including bodily function, neural activity, and molecular signaling. Sleep is conserved across evolution, though significant variations in sleep duration, architecture, and behavior are found across phyla. Decoding neural processing underlying behavior, including sleep, is a fundamental aim in neuroscience, and understanding how such behavior has evolved remains largely unknown. The encompassing goal of this dissertation is to elucidate the genetic and neuronal factors at play in the evolution of sleep loss in the blind Mexican tetra, Astyanax mexicanus. To this end, the work found within will explore peripheral sensory systems regulating distinct mechanisms of sleep loss, demonstrate how evolved changes in specific hypothalamic circuits drive sleep reductions, apply computational techniques to understand whole-brain evolution, and finally, will show how the generation of transgenic tools in a novel model system can be harnessed to assist functional experimental paradigms in relation to evolution and behavior. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

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Laboratory experiments examined now aggressive behavior, use of space, activity and breathing frequency were affected by the number of fish competing for a concentrated, renewing, intermittent food source. Total aggression rate per fish and the proportion of long chases decreased in larger groups and increased during short periods in which food was unavailable. The proportional use of the area near the food source was maximal at intermediate group sizes suggesting that use of the feeding area was reduced by aggressive defense at low densities and by passive interference at high densities. Air-breathing frequency tended to be lower when food was available than when it was not, suggesting that gouramis reduce their use of atmospheric oxygen when it may result in loss of food to competitors. Group size affects the pattern of food competition more through economic resource defense than through passive interference.

Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references (leaves 89-91). / A geometric model using idealized prey behaviors in reaction to wading bird disturbances was developed to hypothesize how wading bird foraging strategy might most efficiently counter those behaviors. The model suggests that for prey responding to wading bird disturbances with flight response distance strongly negatively correlated to their distance from the point of disturbance, wading birds could employ disturbance facilitated social foraging strategy, thereby increasing individual foraging efficiency and selecting for social foraging. In controlled studies of the reactive behaviors of two primary prey species seen to be taken at disparate rates by solitary and socially foraging herons, schooling Shiner Surfperch exhibited behaviors favoring social foraging in herons, while Staghorn Sculpins exhibited no correlation in their flight response distances relative to their proximity to the disturbance, and seemed unlikely to be more efficiently utilized by socially foraging wading birds.

Orientador: Gilson Luiz Volpato / Banca: Percília Cardoso Giaquinto / Banca: Elisabeth Criscuolo Urbinati / Banca: Anette Hoffmann / Banca: Eunice Oba / Resumo: Esta tese versa sobre relações entre memória e estresse. Assim, inicialmente apresentamos alguns conceitos dessas duas áreas que permeiam os estudos apresentados neste trabalho. O estresse é um fenômeno que tem sido amplamente estudado, tanto por razões teóricas quanto pelas suas implicações em atividades zootécnicas de interesse econômico. O estresse é conceituado como um estado do organismo frente situações de ameaça da perda da homeostase causada por algum fator (o estressor). Esse estado implica num conjunto relativamente padronizado de respostas bioquímicas, fisiológicas e comportamentais. Pickering (1981) apresenta o quadro geral de estresse em peixes. Segundo ele, o estressor provoca estimulação no sistema nervoso autônomo simpático que libera das células cromafins da interrenal catecolaminas para o sangue; estimula também o eixo HPI (hipotálamo-pituitária-interrenal), que libera corticosteróides para a circulação. Dessas respostas primárias são induzidas respostas secundárias que podem mobilizar energia que é então usada para o organismo se ajustar à ameaça imposta pelo estressor. Se esses mecanismos de resposta persistem respostas terciárias ocorrem, como imunossupressão, redução ou inibição do crescimento e funções reprodutivas. Temporalmente, as respostas primárias e secundárias podem ocorrer em segundos, ou algumas horas ou dias; as terciárias geralmente demoram alguns dias para que sejam percebidas. Segundo Moberg (2000), o estado de estresse é aquele em que o organismo usa de suas reservas para enfrentar a situação de ameaça (estressor), e o estado de distresse ocorre quando essas reservas são levadas a limites extremos e o uso de energia e vias metabólicas implica necessariamente na supressão, total ou parcial... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Não disponível. / Doutor

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Observations of habitats are reported. A series of underwater experiments were conducted in natural habitats to answer questions concerning a) why Lamprologus ocellatus and Lamprologus ornatipinnis bury gastropod shells refuges into the substrate, and b) to examine interspecies differences in shell-using behaviours. Some behaviour patterns were analysed using phylogenetic methods. Lamprologus ocellatus and L. ornatipinnis responded to new shells in a variety of ways, shells were moved, buried (and used) or hidden (buried and not used). How shells are utilised seems to be dependant on a complex of factors such as the size and quality of new the shell and the number already in the territory. Shell use may also be affected by neighbour species, sex, size and predation levels. There are interspecific differences in the size of shells used and the methods of shell use. The latter results in species-characteristic shell orientations, vertical burial in L. ocellatus and horizontal burial in L. ornatipinnis. Shell orientation does affect other species/use of shells. Shell movement and vertical orientation appear to be apomorphic while shell hiding and burial are pleisiomorphic within the genus Lamprologus. Numerous cues are involved in stimulating shell burial. Most of these cues are actively sought by the fish by external and internal inspections. Shell burial therefore appears to be a method of reducing the information gathering ability of potential shell-dwelling competitors. Shell burial can therefore be regarded as an investment process which enhances the residents ability to defend its territory. Males can also control the distribution of open shells within teritories and thus control mate access to shells. This behaviour could be a significant factor in the evolution of marked sexual dichromatism exhibited within the genus.

Various aspects of downstream migratory behavior of sockeye salmon fry (pncorhynchus nerka) were examined in a series of field and laboratory experiments. The field work at the Department of tie Environment (Fisheries and Marine Service) Fulton Eiver spawning channels, Babine Lake, British Columbia, was concerned with the predation by rainbow trout (Salmo gairdneri) and whitefish (Prosopium williamsoni) on sockeye fry with various kinds of prior experience. The laboratory studies focused on the effects of exposure to light on the behavior of emerging and recently emerged fry. The results showed that : (1) the number of fry moving downstream varies throughout the nightly migration period; (2) the presence cf predators modifies the movement pattern of migrating fry, such that the fry tend to move downstream over a more concentrated time period; (3) fry response to predators tends not to be predator-specific, migrating fry respond similarly to different species of predators; (4) emergent fry are not all similar in their migratory behavior, some tend to migrate rapidly (fast migrants), while others migrate at a slower rate (slow migrants); (5) generally fry with prior experience to predators displayed different migratory behavior compared to fast and slow migrants; and (6) subjecting newly-emerged fry to increasing time periods of light treatment and fry densities, alters behavior patterns. It is concluded that fry commencing downstream movement are not all similar in their migratory behavior. Begardless of the basis for the behavioral difference between fast and slow migrants, the presence of predators modifies and enhances downstream movement. Further, subjecting premigratory fry to light, alters downstream movement and behavioral interactions between fry. / Science, Faculty of / Zoology, Department of / Unknown