Description
The occurrence and severity of extreme climatic events is expected to increase in the future. Extreme climatic events, such as droughts, can have devastating effects on freshwater ecosystems. Aquatic insects have adapted strategies to tolerate or survive climatic disturbances, such as dispersing to a more suitable habitat. Temperature and water level are two environmental factors known to trigger dispersal in aquatic insects. However, little is known on how those two factors can interact together in triggering dispersal. In this work, the combined effects of temperature and water level on the initiation of dispersal by crawling and/or flight in aquatic beetles of the family Haliplidae were evaluated through a fully factorial experiment. Three temperatures and three water levels were combined to create 9 treatment conditions. We recorded beetle behavior in response to the conditions and found that at low temperature, more beetles dispersed at low water level than at high water level. However, at medium and high temperatures, dispersal did not vary across water levels. Our findings suggest that increased temperature is the principal stimulus for dispersal and that water level is important in the context of lower temperatures.
The Effect of Temperature and Water Level on Dispersal in Crawling Water Beetle Family Haliplidae
The occurrence and severity of extreme climatic events is expected to increase in the future. Extreme climatic events, such as droughts, can have devastating effects on freshwater ecosystems. Aquatic insects have adapted strategies to tolerate or survive climatic disturbances, such as dispersing to a more suitable habitat. Temperature and water level are two environmental factors known to trigger dispersal in aquatic insects. However, little is known on how those two factors can interact together in triggering dispersal. In this work, the combined effects of temperature and water level on the initiation of dispersal by crawling and/or flight in aquatic beetles of the family Haliplidae were evaluated through a fully factorial experiment. Three temperatures and three water levels were combined to create 9 treatment conditions. We recorded beetle behavior in response to the conditions and found that at low temperature, more beetles dispersed at low water level than at high water level. However, at medium and high temperatures, dispersal did not vary across water levels. Our findings suggest that increased temperature is the principal stimulus for dispersal and that water level is important in the context of lower temperatures.