caa a22 4500 465782124 CHVBK 20180323111958.0 cr unu---uuuuu 170327e19900401xx s 000 0 eng 10.1007/BF00178321 doi (NATIONALLICENCE)springer-10.1007/BF00178321 Kruse Kipp Department of Zoology, Eastern Illinois University, 61920, Charleston, IL, USA aut Male backspace availability in the giant waterbug ( Belostoma flumineum Say) [Elektronische Daten] [Kipp Kruse] Summary: Following bouts of courtship and copulation, female giant waterbugs (Belostoma flumineum Say) deposit eggs on the backs of their mates. Throughout a 6- to 12-day brooding period, males display several behaviors that are vital to egg-nymph survival. Consequently, females depend on male post-copulatory behaviors for successful reproduction and the possibility exists for male backspace availability to limit female reproduction in this species. I studied seasonal trends and factors that affect male backspace availability in populations of B. flumineum in east-central Illinois (USA). Early in the spring/summer, giant waterbug populations are relatively small and a large majority (188/205=91.7%) of the males are egg-laden; males experimentally added to the population during this period quickly became encumbered. In contrast, later in the summer after young-of-the-year emerge as adults, the waterbug population density increases dramatically and fewer (670/1274\2= 52.6%) of the males are encumbered (egg-laden). Of the males that are egg-laden both early and late in the season, significantly more are completely encumbered (i.e., 100% of the dorsum egg covered) early in the spring. The adult sex ratio is generally not biased and the number of eggs/pad that completely covers a male approximates a full ovarian complement. Therefore, these factors probably do not cause male backspace to become limited. The primary factor that appears to limit male backspace availability is the ability of females to synthesize a second partial clutch in a short time, often within 1 to 4 days. Females are capable of ovipositing partial clutches on 12 males within 30 days, whereas male brooding period is temperature dependent and ranges from 6 to 13 days. Newly emerged males are capable of breeding significantly sooner than can newly emerged females, thereby creating ample oviposition substrate for the females in the population after young-of-the-year adults appear. The evolution of sex-role reversal is not well understood; however it should not evolve in waterbugs unless male backspace limits female reproduction. Such a situation appears to exist in B. flumineum early in the season but not later in the summer. Springer-Verlag, 1990 Behavioral Ecology and Sociobiology Springer-Verlag 26/4(1990-04-01), 281-289 0340-5443 26:4<281 1990 26 265 https://doi.org/10.1007/BF00178321 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00178321 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Kruse Kipp Department of Zoology, Eastern Illinois University, 61920, Charleston, IL, USA aut NATIONALLICENCE 773 0- Behavioral Ecology and Sociobiology Springer-Verlag 26/4(1990-04-01), 281-289 0340-5443 26:4<281 1990 26 265 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer