Abstract
In variable environments, sampling information on habitat quality is essential for making adaptive foraging decisions. In insect parasitoids, females foraging for hosts have repeatedly been shown to employ behavioral strategies that are in line with predictions from optimal foraging models. Yet, which cues exactly are employed to sample information on habitat quality has rarely been investigated. Using the gregarious parasitoid Nasonia vitripennis (Walker; Hymenoptera: Pteromalidae), we provided females with different cues about hosts to elucidate, which of them would change a wasp's posterior behavior suggesting a change in information status. We employed posterior clutch size decisions on a host as proxy for a female's estimation of habitat quality. Taking into account changes in physiological state of the foraging parasitoid, we tested whether different host qualities encountered previously change the subsequent clutch size decision in females. Additionally, we investigated whether other kinds of positive experiences—such as ample time to investigate hosts, host feeding, or egg laying—would increase a wasp's estimated value of habitat quality. Contrary to our expectations, quality differences in previously encountered hosts did not affect clutch size decisions. However, we found that prior egg laying experience changes posterior egg allocation to a host, indicating a change in female information status. Host feeding and the time available for host inspection, though correlated with egg laying experience, did not seem to contribute to this change in information status.
Highlights
We here use clutch size decisions of the pteromalid wasp Nasonia vitripennis to elucidate, which cues are used by females to estimate habitat quality
Within the group of females that had laid eggs during the prior experience, we found no significant effect of number of eggs laid on this host (which might be used as a fine-scaled measurement of host quality (Froissart et al, 2012)) on clutch size on the testing host, when correcting for female egg load (GLM, Poisson distribution, N = 30: df = 1, χ2 = 0.57, p = .450)
Females did not alter their clutch size decisions on the subsequent testing host in response to previous host quality (Table 1). This indicates that changes in host quality are not used by N. vitripennis females to change their estimate of habitat quality, which is in contrast to many other species studied (e.g., Bezemer & Mills, 2003; Louapre, Baaren, Pierre, & Alphen, 2011; Rosenheim & Rosen, 1991; Wajnberg, 2006)
Summary
We here use clutch size decisions of the pteromalid wasp Nasonia vitripennis to elucidate, which cues are used by females to estimate habitat quality. The study revealed physiological state and experience (information) based decisions, by manipulating egg load through size and rearing temperature of experimental females (Rosenheim & Rosen, 1991).
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
