The “little bats” are the MYOTIS GROUP:
California Bat Myotis californicus
One of the smallest BC bats.
Wingspan 21-25cm. Small forearm 29-35mm. Wt 3.3-5.4g.
Fairly long ears, extend just beyond nose, long narrow tragus.
Dull rusty to blackish brown fur.
(Similar species: Long-legged – but shorter forearm. Yuma & Little brown – but has keel on calcar).
- Uses diverse habitats, has small maternal colonies, is flexible in choice of night roosts.
- One pup/year.
- May be active on southern coast in winter, often hibernates in buildings, occasionally emerges to forage.
- Range: western NA from southern Mexico to Alaska.
Painting Credit: Wendy Smith from Kays and Wilson’s Mammals of North America, © Princeton. Accessed 2017 at http://naturalhistory.si.edu/mna/full_image.cfm?image_id=1580
Long-legged Bat Myotis volans
Medium-sized “little’ bat.
Wingspan 22-27cm. Wt 6-10g. Forearm 34- 43 mm.
Ears smaller, barely reach nose.
Red-brown to nearly black fur. Fur on wings extends to knees & elbows.
(Similar species: California – but longer forearm. Big brown – but shorter forearm & has fur on wings).
- Roosts under bark, in snags, tree & rock crevices & buildings. Uses maternal colonies.
- 1 pup/year.
- Broad range of insect prey.
- Hibernates in mines & caves, also in northern range.
- Range: western NA, central Mexico to SW Alaska.
Photo Credit: Photographer Carson Brown. Accessed 2017 at http://batsoftexas.com/species/myotis-volans/
Little Brown Bat Myotis lucifugus Canada Endangered
Medium-sized ‘little’ bat. Wingspan 22-27cm. Wt 6-10g.
Ear medium length, reach nostrils.
On coast, blackish fur, long, glossy. Lighter undersides. Dark brown ears & wings.
(Similar species: California & Long-legged – but lacks keel on calcar. Yuma – but often more aggressive when handled. Need DNA or acoustic calls to separate from Yuma).
- Wide range of habitats. Summer often roosts in buildings, also under bark & tree & rock cavities. Females in large maternal colonies in hot (30-55ºC) sites.
- 1 pup/year, v. rarely twins.
- Broad variety of prey, diet varies with insect abundance, usually caught & eaten in flight.
- Hibernates Sept-Oct to April-early May in caves & mines that may be some distance from summer habitat.
- Range: Formerly across NA, now populations being decimated by White Nose Syndrome in hibernacula.
Photo: J. Balke, Denman Island
Western Long-eared Bat Myotis evotis
Large “little bat. Wingspan 24-29cm. Wt 4-9g.
Ears long, extend 5mm or more beyond nose.
On coast fur usually dark brown nearly black.
(Similar species: Keen’s long-eared – Impossible to tell in field).
- Wide range of habitats, sea level up to 1220m on coast. Small maternal colonies usually in buildings, 5-30 bats & may have some males. Also roost under tree bark, in caves, mines, crevices in rocks & trees & may roost at ground level.
- 1 pup/year.
- Main prey – moths, also feeds on beetles, flies & spiders. Quiet, short-duration, high-pitched calls, good for hunting in heavy vegetation. Hunts in flight & gleans off vegetation & ground.
- Hibernates in mines & caves, few records.
- Range: western NA, from Bella Coola, BC to Baja.
Photo Credit: Katrina Smith Accessed 2017 at https://www.nps.gov/labe/learn/nature/bat-species.htm
Yuma Bat Myotis yumanensis
Medium-sized “little’ bat. Wingspan 21-26cm. Wt 4-9g.
Ears medium length, reach nostrils.
Back fur pale brown to almost black, paler under.
(Similar species: Long-legged & California – but no calcar keel. Little brown –
Need DNA or acoustic calls to separate).
- Closely associated with water. Roosts usually buildings, also caves, tree & rock crevices. Maternal colonies may be large to 2000, Males alone or small groups.
- 1 pup/year.
- Feeds on aquatic insects, esp. midges.
- BC hibernacula unknown, caves used in Wa.
- Range low elevation in BC to 730m, from western NA, Mexico to S. BC.
Photo Credit: Photo copyright Michael Durham/Minden Pictures/Bat Conservation International Accessed 2017 at https://www.nps.gov/labe/learn/nature/bat-species.htm
Not confirmed on Denman:
Keen’s Long-eared Bat Myotis keenii
Medium-sized “little” myotis group bat.
Wingspan 21-26cm. Wt 4-5.9g.
Fairly long ears that extend beyond nose & long narrow pointed tragus. Dark glossy fur, undersides paler. Dark brown ears & wing membrane. (Similar Species: Western long-eared – Impossible to tell in field).
- Forest bat forages on arthropods in-flight & gleaning off vegetation.
- Very low echolocation calls.
- Range: Pacific northwest coast of NA. Only known maternal colony in BC in Gwaii Haanas National Park Reserve.