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[Objectives] To obtain the characteristics of the migrating Mythimna separata (Walker) during the peak migration episode in 2013 from the doppler weather radar echoes, and explore the relationship between the numbers resolved from radar echoes and the catch sizes from search light traps, which would provide a foundation to monitor insect migration with doppler weather radar. [Methods] The CINRADSA weather radar data in Beijing and the interval catch sizes from searchlight trap during the migrating peak days of the first generation moths of M. separata in 2013 were selected, and the weather radar data were extracted, retrieved, calculated, counted, analyzed and visualized with some libraries in Python and R. [Results] The number of the M. separata moths from searchlight trap at Yanqing accounted for more than 80% every night from 5th to 9th in June, and the reflectivity between 15 dBZ and 15 dBZ of the echoesfrom the insect swarms above the monitoring site was more than 90%, of which the number of radar echoes from 0 to 15 dBZ accounted for 30.7%, 42.0%, 43.2%, 37.2% and 25.1%, respectively, the trend was similar with the proportion of the M. separata moths from searchlight trap. The direction of the target echoes was northward on average from 5th to 8th in June and southward on 9th. The proportion of echoes with northward direction has the similar trend with the proportion of the M. separata moths from searchlight trap, and the correlation coefficient between them is 0.95. The average speed of the northward echoes from 5th to 8th is close to the wind speed, however the displacement speed is 1.36 m/s on the 9th, which is close to its own flight speed. The number of the M. separata moths retrieved from weather radar data was positively linearly correlated with the number of the M. separata moths from searchlight trap. The maximum of M. separata moths flying over Beijing within the radar monitoring range (approximately 4 300km2) in one night reached to 6 million heads, and the total mass was more than 0.8 tons. [Conclusion] Doppler weather radar can observe the characteristics of the migrating M. separata moths during the peak episode, and these parameters help in understand the migration of M. separata. [ABSTRACT FROM AUTHOR]

In addition to sperm, some accessory substances transferred to females during copulation act as nuptial gifts by passing on valuable nutrients in many insect species. The nutritional status of the males can thus have a great effect on the mating behavior, fecundity and even the longevity of females. However, little is known about the effect of male nutritional status on the female reproductive traits in migratory insect species, particularly when females experience nutrient shortage and have to choose between reproduction and migration. Here, Cnaphalocrocis medinalis, a migratory rice pest in Asia, was studied to explore this issue. Our results showed that in male moths fed with honey solution, their gonads had higher energy content than gonads of starved males, resulting in increased energy content of the bursa copulatrix of females after mating with fed males. Such females showed increased mating frequency, fecundity and longevity compared to females mating with starved males, indicating that male moths deliver nuptial gifts to females and improve their reproductive performance. However, when females were starved, only about 45% mated, with just a single copulation, regardless of male nutritional status. Starved females showed lower fecundity, and a longer pre‐oviposition period (indicating a greater propensity to migrate), compared to fed females. However, copulation still significantly extended their longevity. These results suggest that starved females invest in migration to escape deteriorating habitats, rather than investing the nuptial gift to increased fecundity. Our results further our understanding of the reproductive adaptability of migratory insects under conditions of food stress. [ABSTRACT FROM AUTHOR]