caa a22 4500 469098953 CHVBK 20180323133039.0 cr unu---uuuuu 170328e19920501xx s 000 0 eng 10.1007/BF00317181 doi (NATIONALLICENCE)springer-10.1007/BF00317181 Attack strategy of ladybird beetles (Coccinellidae): factors shaping their numerical response [Elektronische Daten] [J. Hemptinne, A. Dixon, J. Coffin] Summary: Temporal changes in aphid abundance pose a considerable challenge to ovipositing aphidophagous ladybirds, as in order to maximize their fitness they need to synchronize their reproduction with the early development of aphid populations. Field census data and laboratory experiments were used to determine how ovipositing females of the two-spot ladybird, Adalia bipunctata (L.), assess whether an aphid population is suitable for exploitation. In the field, two-spot ladybirds usually laid eggs well before aphid populations peaked in abundance. In the laboratory they showed a marked reduction in their reproductive numerical response in the presence of larvae of their own species but not of other aphidophagous ladybirds. At the highest aphid density this was not a consequence of competition for food between larvae and ovipositing females. In the presence of conspecific larvae gravid females were very active and as a consequence more likely to leave an area, and when confined with other conspecific females or larvae laid fewer eggs and later than females kept on their own. The extent of the inhibition of egg laying is negatively correlated with the rate of encounter with larvae. Thus it is proposed that gravid females appear mainly to use the presence of conspecific larvae to assess the potential of an aphid colony for supporting the development of their offspring. Springer-Verlag, 1992 Ladybird beetles nationallicence Oviposition nationallicence Numerical response nationallicence Hemptinne J. School of Biological Sciences, University of East Anglia, NR4 7TJ, Norwich, UK aut Dixon A. School of Biological Sciences, University of East Anglia, NR4 7TJ, Norwich, UK aut Coffin J. School of Biological Sciences, University of East Anglia, NR4 7TJ, Norwich, UK aut Oecologia Springer-Verlag 90/2(1992-05-01), 238-245 0029-8549 90:2<238 1992 90 442 https://doi.org/10.1007/BF00317181 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00317181 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hemptinne J. School of Biological Sciences, University of East Anglia, NR4 7TJ, Norwich, UK aut NATIONALLICENCE 700 1- Dixon A. School of Biological Sciences, University of East Anglia, NR4 7TJ, Norwich, UK aut NATIONALLICENCE 700 1- Coffin J. School of Biological Sciences, University of East Anglia, NR4 7TJ, Norwich, UK aut NATIONALLICENCE 773 0- Oecologia Springer-Verlag 90/2(1992-05-01), 238-245 0029-8549 90:2<238 1992 90 442 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer