Nyctalus aviator, Thomas, 1911

Don E. Wilson & Russell A. Mittermeier, 2019, Vespertilionidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 716-981 : 765

11.

Bird-like Noctule

Nyctalus aviator

French: Noctule aviatrice / German: GroRRer Ostasien-Abendsegler / Spanish: Noctulo oriental

Other common names: Japanese Large Noctule

Taxonomy. Nyctalus aviator Thomas, 1911 ,

“ Tokyo, Hondo [= Honshu], Japan.”

Nyctalus aviator is sometimes included within N. lasiopterus , from which it is morphologically distinct, but to which it is genetically sister. N. aviator and N. lasiopterus are togethersister to N. noctula , all three sharing the same diploid number. Monotypic.

Distribution. NE & EC China (Heilongjiang, Jilin, Henan, Anhui, and Zhejiang), Korean Peninsula, and numerous islands in Japan (Hokkaido, Honshu, Shikoku, Kyushu, Tsushima, Iki, Fukue, and Okinawajima); there are also visual and echolocation records from the Russian Far East, but further investigation is needed.

Descriptive notes. Head-body 80-106 mm, tail 45-62 mm, ear 16-23 mm, hindfoot 12-17 mm, forearm 58-64 mm; weight 26-61 g. Pelage of the Bird-like Noctule is velvety and deep yellowish brown throughout, being slightly lighter ventrally. Ears, face, wings, and uropatagium are mid-brown. Thumbs and ears are short, and tragus short and stubby, with a rounded tip; antitragus is long and low. Muzzle is short, with large glands between nostrils and eyes, and ears are short and triangular, with 4-5 folds on outer edge. Calcar is keeled, and wing membraneis attached to ankle. Skull is broad and robust; postorbital process is weak. I? is longer than I’; teeth are large with low cusps; lower molars are nyctalodont. Chromosomal complement has 2n = 42 and FN = 50.

Habitat. Found primarily in mountainous regions with temperate deciduous forests.

Food and Feeding. Insectivorous and carnivorous. The Bird-like Noctule is a large, fast aerial hawker that feeds on a variety of insects, as well on occasion as nocturnally migrating birds. In fecal samples collected in Japan, bird bones and feathers were detected, although these bats have never been directly observed hunting birds. The species is known to feed on a variety of insects, including various mayflies, dragonflies, damselflies, grasshoppers, hemipterans, beetles, ichneumonids, winged ants, syrphid flies, chironomid flies, trichopterans, and lepidopterans. In Japan, Coleoptera made up a large portion of the diet, comprising 40-51-2% of arthropod fragments in fecal samples, although Lepidoptera were also significant, ranging 11-34-1% of fragments throughout the year.

Breeding. Mating takes place in autumn, up to early October, before hibernation; ovulation and fertilization are delayed, and sperm is stored until next spring. Births generally occurin lateJune and earlyJuly;litter size is 1-2 (normally two). Young begin to fly at ¢.40-45 days; females generally start breeding in their first autumn.

Activity patterns. The Bird-like Noctule is primarily nocturnal throughout its active months, although it is known to forage during the day when energy demands are high, right after leaving hibernation (March to early April) and just before entering hibernation (October to late November); hibernates in colonies. Diurnal roosts are often found in tree cavities, buildings, bird boxes, and mineshafts. Bats leave the roost in early evening and spend the night foraging high in the forest canopy. Calls are FM for the scanning phase and long duration QCF in the search phase; they have a general frequency range of c¢.17-30 kHz,start frequency range of 27-1-54-1 kHz, and end frequency range of 17-6-22-6 kHz; call durations are 2-2-17-8 milliseconds. Bird-like Noctules are known tolive for at leastsix years. In Japan, the gyrfalcon (Falco rusticolus) has been reported as a predator.

Movements, Home range and Social organization. Bird-like Noctules roost in small colonies and probably migrate between breeding and hibernating areas during autumn and spring. During summer and the breeding season, females form large maternal colonies of tens to over 100 individuals, while males form small male-exclusive colonies of 1-10 individuals. During and a little before and after hibernation, however, the species forms colonies consisting of several to tens of individuals of both sexes (October to May).

Status and Conservation. Classified as Near Threatened on The IUCN Red List. The Bird-like Noctule is relatively widespread and moderately common, although it is threatened by deforestation and other forms of human disturbance.

Bibliography. Abe et al. (2005), Brazil & Sasaki (2004), Datzmann et al. (2012), Fukui, Agetsuma & Hill (2004), Fukui, Dewa et al. (2013), Harada, Uchida et al. (1982), Jo Yeong-Seok et al. (2018), Maeda (1983), Mikula et al. (2016), Ohdachi et al. (2009), Osawa et al. (2017), Salgueiro et al. (2007), Smith & Xie Yan (2008), Tsytsulina (2008a), Yoshiyuki (1989).

Figures

1. Desert Yellow Lesser House Bat (Scotoecus pallidus), 2. Dark-winged Lesser House Bat (Scotoecus hirundo), 3. Light-winged Lesser House Bat (Scotoecus albofuscus), 4. Ruppell’s Bat (Vansonia rueppellii), 5. Indochinese Thick-thumbed Bat (Glischropus bucephalus), 6. Dark Thick-thumbed Bat (Glischropus aquilus), 7. Common Thick-thumbed Bat (Glischropus tylopus), 8. Javan Thick-thumbed Bat (Glischropus javanus), 9. Dormer’s Bat (Scotozous dormeri), 10. Chinese Noctule (Nyctalus plancyi), 11. Bird-like Noctule (Nyctalus aviator), 12. Japanese Noctule (Nyctalus furvus), 13. Mountain Noctule (Nyctalus montanus), 14. Greater Noctule (Nyctalus lasiopterus), 15. Common Noctule (Nyctalus noctula), 16. Leisler’s Noctule (Nyctalus leisleri), 17. Azores Noctule (Nyctalus azoreum)

Distribution. NE & EC China (Heilongjiang, Jilin, Henan, Anhui, and Zhejiang), Korean Peninsula, and numerous islands in Japan (Hokkaido, Honshu, Shikoku, Kyushu, Tsushima, Iki, Fukue, and Okinawajima); there are also visual and echolocation records from the Russian Far East, but further investigation is needed.