Change of Foraging and Hiding Behaviors in the Pacific Abalone Haliotis discus hannai in Response to Elevated Seawater Temperature

Abstract

Ocean warming induced by high CO 2 emission is expected to change the behavior of many marine poikilotherms. During the day, abalones take shelter under rocks or in crevices from which they emerge to forage in the evening. In this study, we explored the effect of changing seawater temperature on the foraging and hiding behaviors of the juvenile Pacific abalone Haliotis discus hannai. First, we tested whether their hiding behavior in response to light differs depending on the temperature (11°C, 14°C, and 17°C) when only artificial shelter was provided. We observed that the abalones hid under the shelter much faster at 17°C than at 11°C. Second, we tested whether their hiding and foraging behaviors changed in response to increasing temperature when both food and shelter were provided. At high water temperature (17°C), abalones emerged more quickly than at low water temperature (11°C), and the total number of feeding abalones was higher at high temperature than that at low temperature. However, the hiding speed in response to light in the morning was not significantly different among different temperatures. These results suggest that although the basic response to a single stimulus (i.e., light or food) was faster at higher temperatures than at lower temperatures, abalones may increase their boldness under higher temperatures when deciding whether to feed or hide.

The Effects of Temperature and Salinity Stressors on the Survival, Condition and Valve Closure of the Manila Clam, Venerupis philippinarum in a Holding Facility

“…Temperature and salinity are important environmental factors affecting the survival of marine benthic organisms, and increasing temperatures and decreasing salinity can act as dominant physical stressors [9]. The reported effects of an increase in temperature include changes in growth [10,11], behavior [12,13], metabolism [14,15], and mortality [12,16]. Salinity effects include abnormal endogenous rhythms [17], changes in behavior [18][19][20], decreased condition index [21,22], and increased mortality [23].…”

The Effects of Temperature and Salinity Stressors on the Survival, Condition, and Valve Closure of the Manila Clam, Venerupis philippinarum in a Holding Facility

“…Temperature and salinity are important environmental factors affecting the survival of marine benthic organisms, and increasing temperatures and decreasing salinity can act as dominant physical stressors [9]. The reported effects of an increase in temperature include changes in growth [10,11], behavior [12,13], metabolism [14,15], and mortality [12,16]. Salinity effects include abnormal endogenous rhythms [17], changes in behavior [18][19][20], decreased condition index [21,22], and increased in mortality [23].…”