We studied the effect of physiological age on the oviposition behavior of Aedes aegypti following two successive gonotrophic cycles using a choice experiment under laboratory conditions. Blood-engorged mosquitoes (n=10) were introduced into individual cages that contained four oviposition sites (choices) with different salinities: Distilled water (DW), 0.33% NaCl (T1), 0.67% NaCl (T2) and 1% NaCl (T3). The oviposition substrate (seed germination paper) was changed daily and the number of oviposited eggs (the response variable) was recorded. The initial oviposition activity ceased on the tenth day of the experiment and two days later a second blood-meal was offered to the original cohort of mosquitoes; only five became visibly blood-engorged. The oviposition activity was again followed for 12 additional days. During the first oviposition period (days 1-10 of the experiment), the mosquitoes oviposited predominately in the DW and T1 treatments and completely avoided the T3 treatment (p<0.001). In contrast, the oviposition pattern during the second gonotrophic cycle (days 12-24 of the experiment) was less polarized, suggesting that the physiologically older mosquito may be less selective. The implications of these data are discussed in the context of lethal ovitrap strategies for the control of urban container breeding mosquitoes.

Key Words: 1) Aedes aegypti (The Yellow Fever Mosquito); 2) Oviposition Choice; 3) Gonotrophic Cycle