Avery, D. E.. University of Rhode Island/Graduate School of Oceanography, davery@gso.uri.edu
, . E.. ,

 
PROXIMAL CUES TO AND INDIVIDUAL VARIATION IN RESTING EGG PRODUCTION BY THE COPEPOD ACARTIA HUDSONICA IN NARRAGANSETT BAY, RI, USA
 
Females of the copepod Acartia hudsonica in Narragansett Bay, R.I. produce resting eggs as summer approaches. I completed experiments to: 1) describe the population-level switch from immediately-hatching to resting egg production; 2) determine the proximal environmental cues triggering the switch; and 3) quantify the variation in switching response among individuals. The population produced an increasing mean proportion of resting eggs between March 13, 1998 (about 1%) and June 23, 1998 (about 60%) when individuals were held in the laboratory at ambient conditions of temperature and photoperiod. Adult female copepods also responded to short-term (3-day) experimental increases in temperature by increasing the mean proportion of resting eggs they produced. In several experiments throughout the spring, individuals varied greatly in their responses. For example, on June 23, 90% of females produced resting eggs, but individual responses ranged from 0% to 100% resting eggs produced. These results have implications for the population dynamics of this species as well as the community composition in Narragansett Bay. The variation observed may have consequences for individual fitness and, therefore, requires explanation.
 
Day: Thursday, Feb. 4
Time: 02:15 - 02:30pm
Location: Hilton of Santa Fe
 
Code: SS24TH0215H