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Behavioral And Physiological Responses Of The Lobster, Homarus Americanus, To Temperature: A New Synthesis, Steven Harold Jury

Doctoral Dissertations

Temperature has a pervasive influence on lobster behavior, physiology and ecology and affects their subsequent distribution in thermally variable habitats such as estuaries and coastal areas. A multidisciplinary approach, including field and laboratory studies, was used to show: (1) that lobsters sense temperature with warm and cool thresholds as small as 0.1--0.2°C; (2) the relationship between temperature and activity is not linear, but instead switches between a high activity level in warmer months (10--20°C) and a lower level in colder months (<10°C) with transition periods in the spring and fall; (3) Parallel studies in the lab and field show that daily levels of activity are not greatly influenced by small temperature variations (i.e. tidally induced changes of 14°C), but activity levels are significantly higher in the field (249 +/- 55.1 m/d) than in the laboratory (88 +/- 12.0 m/d); (4) lobsters prefer a narrow range of temperatures over others available in a thermal gradient and avoid temperatures >23.5 +/- 0.4°C, suggesting that they behaviorally thermoregulate. While this preferred temperature shifts seasonally, the final preferred temperature …