Kimitake Funakoshi

Postnatal growth and vocalization development of the lesser horseshoe bat, Rhinolophus cornutus, in the Kyushu District, Japan

Abstract. Postnatal growth and vocalization development in the lesser horseshoe bat, Rhinolophus cornutus, were investigated in the Kyushu District. Parturition occurred in early June. Forearm length of newborn young averaged 16.5 mm in females and 16.3 mm in males, and their body weight averaged 2.4 g. The newborn young at a few days of age were left alone or in a small loose cluster at night. However, mothers returned to the nursery roost from foraging one or two hrs after sunset and embraced their young until sunset, while mothers embraced them three hrs after sunset at colony-forming stage. From newborn to colony-forming stage, forearm length and body weight of young increased noticeably, whereas from colony forming to flying stage growth rates slightly slowed down, especially the rates being more marked in a large colony than in a small colony. From flapping to flying stage, there were two peaks of mothers embracing behavior at night, while most of the young clustered tightly and formed a large colony. Fundamental frequency of calls in a few-day-old young averaged 19.8 kHz. From newborn to colony-forming stage, the number of harmonics reduced 5–6 to 3–4 in both the oral and nasal calls. At flapping stage, oral calls with two or three syllables, contained two or three harmonics, and their fundamental frequency averaged 32.1 kHz, while nasal calls contained only two harmonics, and their frequency averaged 42.6 kHz. At flying stage, young emitted nasal pure tone CF-FM or FM-CF-FM calls, and the second harmonic became more intense than the first one. The dominant frequency of CF-components from flying to self-supporting stage is negatively correlated with the size of forearm length.

Development of Sounds During Postnatal Growth of the Eastern Bent-Winged Bat Miniopterus fuliginosus

The eastern bent-winged bat Miniopterus fuliginosus is widely distributed from Afghanistan to India, as well as in China, the Korean Peninsula, and Japan (Maeda 1982). In Japan, these bats are found on the islands of Honshu, Shikoku, and Kyushu (Maeda 1978; Yoshiyuki 1989; Sawada 1994). M. fuliginosus moves seasonally and form large maternity colonies (Funakoshi 1986). Bats fly swiftly and prey on flying insects in the space above the treetops (Funakoshi and Uchida 1975). They emit a dual echolocation call consisting of frequency modulation (FM) and quasi-constant frequency (FM/ QCF) portions. The FM/QCF portion consists of two components: the pulse begins with FM and then moves to a shallow FM in the latter part of the call (Funakoshi 2010). Echolocation signals are species-specific and correlate with the type of foraging strategy used by the emitter (Neuweiler 2000; Schnitzler and Kalko 2001; Schnitzler et al. 2003). Most young bats are capable of echolocation behavior immediately before weaning (flying stage). Ontogeny of the FM and/or FM/QCF portion has been studied in some insectivorous bats (Gould 1971, 1975; Buchler 1980; Thompson et al. 1985; Moss 1988; Jones et al. 1991; Moss et al. 1997; Yamasaki and Matsumura 2004; Yamasaki et al. 2006; Monroy et al. 2011). There is, however, no report regarding the ontogeny of calls of bats in the subfamily Miniopterinae or genus Miniopterus that fly swiftly and forage in open spaces and feed mainly on small or medium-sized moths (Funakoshi and Uchida 1975; Nowak 1994; Funakoshi and Takeda 1998). In this paper, we provide new information on the ontogeny of the vocalizations of this species in conjunction with postnatal growth. We focused on analyzing the spontaneous vocalization development of infant M. fuliginosus to determine whether these vocalizations serve as precursors of echolocation calls. Study area and methods

Night-roost usage and nocturnal behavior in the Japanese house-dwelling bat, Pipistrellus abramus

Abstract. Night-roost usage and nocturnal behavior in Pipistrellus abramus were examined in the school buildings in Kagoshima Prefecture. Night-roosts were used from May to October, with their peak in August. The bats began to use night-roosts at about 80 min after sunset, and left the roosts at about 70 min before sunrise. Solitary roosts were almost exclusively occupied by males, while colonies at the night-roosts consisted of females and/or young, and attained the maximal size of 30 bats in August. The night-roosts were warmer than ambient at night, and firstly provided sites for resting between feeding bouts, promoting digestion of food or absorption of nourishment. The duration of roosting bouts at night varied from 0.5 to 7.6 hrs, and became longer in September. Adult females and males occupied different night-roosts in general. Females of P. abramus were faithful to particular night-roosts, while males did not defend night-roosts, and frequently changed their roosts. Copulation did not occur at the night-roosts.

Annual Molting Cycle and Photoperiods That Affect Seasonal Coat Color Changes in the Japanese Marten (Martes melampus)

Abstract. External factors that affect seasonal coat color changes in the Japanese marten (Martes melampus) were examined under experimental conditions. In martens, captured in Kagoshima Prefecture and exposed to a photoperiod of 10L: 14D with light intensity of 20–70 lux, molting rhythms did not synchronize with each other over six years, regardless of ambient temperature fluctuations. The cycle length from the start of one blackish color change to the next was approximately 14 months. This may be caused by a modifiable endogenous circannual rhythm that may be reset by external photoperiods. For the male kept at 14L: 10D with light intensity of 600 lux, duration of activity was 13 h, and his fur remained blackish without change for three years. The fur of female, kept under the same conditions, changed to yellowish when the duration of activity changed to 9 or 10 h, and subsequently remained brackish without molting when the duration changed to 13 h. These results show that length of time exposed to light per day is an important factor that affects coat color changes. The camera trapping survey revealed that martens with brackish coat color in winter may inhabit Kagoshima Prefecture without molting although they were rare.

Ecology and Monogamous System of the Painted Woolly Bat Kerivoula picta in Khon Kaen, Thailand

Abstract. Day-roost usage, nocturnal activity, foraging area, and social structure of the painted wooly bat, Kerivoula picta, were investigated at the village of Khon Kaen in northwest part of Thailand. The bats mainly preferred dead banana leaves as day-roosts, while leaves of sugar cane or broad-leaved trees were occasionally used. They frequently switched their day-roosts every one to four days. Families numbering three bats (adult female, adult male, and young) were found in February, June, September and October. However, such families were not found in November and December when pairs constituted 64% of the total number of captured bats. Most of the pairs roosted together in day-roosts, and did not change their partners during the survey period each year. Foraging areas between contiguous pairs did not overlap each other. Foraging areas averaged 6.1 ha for males and 5.6 ha for females. Kerivoula picta fed chiefly on relatively small-sized web-building spiders. Most of the pairs changed partner every year. The recapture rates of newly banded bats after one year averaged 20%, and the oldest ages recorded were five years for females and four years for males.