70.

Southern Forest Bat

Vespadelus regulus

French: Vespertilion de King River / German: Sidliche Waldfledermaus / Spanish: Vespadela de King River

Other common names: King River Little Bat, King River Pipistrelle, Little Bat

Taxonomy. Pipuistrellus regulus Thomas, 1906,

“King River ... near Albany, King George’s Sound [Western Australia, Australia]. Sea-level.”

Vespadelus regulus may actually comprise two distinct species, one in the east and the other in the west. Monotypic.

Distribution. S & SE Australia, from S Western Australia to Victoria, S & E New South Wales, and extreme SE Queensland; also Kangaroo I and Tasmania.

Descriptive notes. Head—body 36-2-46-6 mm, tail 28-5-39 mm, ear 9-12-9 mm, forearm 28-34-4 mm; weight 3-6-7 g. Dorsal pelage varies from reddish brown to brown to gray; ventral pelage is generally gray to grayish white (hairs distinctly bicolored, with dark base). Ears and wings are dark gray, and face is pinkish brown. Ears are small and rounded triangular with smoothly convex anterior edge; tragus is narrow, anteriorly straight or slightly concave, posteriorly convex, and with rounded tip and slight posterobasal lobe; tragus is usually dark. Uropatagium reachesto tip oftail. Penis is pendulous and clearly swollen; glans penis has deep furrow on underside and is enclosed by large lateral folds, and distal end is smooth and round with a slightly raised dorsal hump; urethral opening is ventral and approximately centrally located on head of glans, and is enclosed by a large lateral fold on either side. Baculum is moderately long (mean 3-8 mm), is elongate dart-shaped in dorsal view, with moderate basal bifurcation, is slightly expanded laterally at base, and is mostly straight in lateral view with tip bent somewhat upward. Skull is of moderate length; lambdoidal crest is moderately to well developed; anterior narial notch is U-shaped; rostrum is moderately long. I? is bicuspid, I’ is unicuspid; P* is much smaller than C!, and within tooth row; crista linking base of metacone and hypocone on M' is absent,slight, or moderate (absent or slight in south-western and eastern distribution), and absent or slight on M2.

Habitat. Occurs in a variety of habitats such as rainforests, wet and dry sclerophyll forests, shrublands and low shrub woodlands, mixed temperate woodlands, mallee, and open woodlands. Recorded from sea level to 1700 m in Victoria.

Food and Feeding. Southern Forest Bats forage in forested areas, particularly in mature forests with dense vegetation. They are very maneuverable and readily fly close to vegetation, making quick spirals and gliding arcs to change direction in pursuit of prey. They can reach speeds of 5-25 km/h. They tend to have a small foraging range of less than 10 ha. Diet varies across the range and by season, based on availability. In Tasmania, they fed mainly on moths and beetles, but also some flies, true bugs, and termites. In Victoria, they ate mostly flies, true bugs, and moths with some beetles,true bugs, and ants.

Breeding. Southern Forest Bats breed once per year before hibernating. Spermatogenesis peaks in January before mating begins in April. Sperm is stored in the epididymis and breeding continues into winter, when males will arouse from hibernation to mate. A copulatory plug develops in the female’s vagina after mating, and ovulation and fertilization are delayed until spring. Gestation takes c.3 months. Litter consists of single young born in late November or early December; weaning takes place after six weeks. Volant subadults first appear in January and February. In southern Tasmania, births occur a month later, from late December to early January. Maximum life span recorded is eight years, with a mean life expectancy of 2-3-2 years.

Activity patterns. Southern Forest Bats forage at night, leaving their roosts at dusk. They appear to become torpid during the day in their roosts, all year. Roosts are selected to be high aboveground in live trees with very little surrounding vegetation. The bats hibernate through winter in a deep torpid state but will wake regularly to forage and mate. Call shape is a steep FM/QCF. There is some variation in characteristic frequency throughout the distribution: 45-46 kHz in north-eastern New South Wales; 40-43 kHz in south-eastern New South Wales; and 54-55 kHz in southern New South Wales.

Movements, Home range and Social organization. Southern Forest Bats roost in colonies of up to 100 individuals in tree hollows or houses. Males usually roost separately from females except during the breeding season. Females seem to roost in larger colonies than males. The bats change roosts frequently, traveling only a short distance to find a new roost.

Status and Conservation. Classified as Least Concern on The IUCN Red List. There are currently no major threats affecting the Southern Forest Bat, although it is sensitive to extreme forest fragmentation, avoiding small forest remnants, corridors, and open areas.

Bibliography. Churchill (2008), Hosken et al. (1998), Kitchener & Halse (1978), Kitchener et al. (1987), Law & Chidel (2002), Law, Chidel & Law (2018), Law, Reinhold & Pennay (2002), Lumsden & Bennett (1995), Lumsden, Reardon & Pennay (2008b), O'Neill & Taylor (1986), Taylor & Savva (1990), Tidemann (1993), Tidemann & Flavel (1987), Tidemann & Law (2008), Turbill (2009), Webala etal. (2010).