Synchronous crepuscular flight of female Asian gypsy moths : Relationships of light intensity and ambient and body temperatures

• Published in: Journal of insect behavior Vol. 12; no. 4; pp. 517 - 531
• Main Authors: CHARLTON, R. E, CARDE, R. T, WALLNER, W. E
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01-07-1999; Springer Nature B.V
• Subjects: Air temperature; Ambient temperature; Animal ethology; Biological and medical sciences; Body temperature; Females; Flight behavior; Fundamental and applied biological sciences. Psychology; Germany; Light intensity; Lymantria dispar; Protozoa. Invertebrata; Psychology. Psychoanalysis. Psychiatry; Russia; Temperature; Eurasia; Europe; Germany; Siberia; Russia; Lymantriidae; Intraspecific relation; Insecta; Body temperature; Flight; Synchronism; Environmental factor; Sunset; Locomotion; Pest; Social interaction; Animal; Arthropoda; Light; Lepidoptera; Female; Invertebrata; Lymantria dispar; Room temperature; Field study
• ISSN: 0892-7553; 1572-8889
• DOI: 10.1023/a:1020918924471

Female gypsy moths (Lymantria dispar) of Asian heritage studied in central Siberia and Germany exhibit a highly synchronous flight at dusk, after light intensity falls to about 2 lux. This critical light intensity sets the timing of flight behaviors independent of ambient temperature. Flight follows several minutes of preflight wing fanning during which females in Germany and those from a laboratory colony (derived from Siberian stock) raised their thoracic temperatures to 32-33°C at ambient temperatures of 19-22°C. Thoracic temperature of females in free flight exceeded the air temperature (19-22°C) by approximately 11-13°C. The duration of wing fanning was strongly dependent on ambient temperature. In Germany, where ambient temperatures at dusk ranged between 21 and 25°C, females wing fanned for only 2.1 ± 0.2 (SE) min; in the much colder temperatures prevalent at dusk in Bellyk, central Siberia (11-13°C), females spent 11.2 ± 0.6 min in preflight wing fanning. The majority (≤80%) of mated and even virgin females initiated flight during the evening of the day they eclosed. However, in Bellyk, a small proportion (12%) of females wing fanned for an extended time but then stopped, whereas others (8%) never wing fanned and, therefore, did not take flight. Females also were capable of flight when disturbed during the daylight hours in Germany where the maximal temperature was high (27-30°C), but not in Siberia, where temperatures peaked at only 17-19°C. However, Siberian females were able to propel themselves off the tree on which they were perched by executing several vigorous wing flicks when approached by the predaceous tettigoniid, Tettigonia caudata.[PUBLICATION ABSTRACT]