Northern Long-eared Myotis
Myotis septentrionalis
Summary 6
The northern long-eared myotis (Myotis septentrionalis) is a small bat, typically 5-10 g and 84 mm in total length. The fur is dull brown on the dorsum and yellowish on the venter. Compared to other Myotis species, these bats have long ears with a relatively long tragus in each ear.
Description 7
The northern long-eared bat is a small bat, measuring an average of 8.6 cm (3.4 in) in total length, including a tail about 4 cm (1.6 in) long. Adults weigh between 5 and 8 g (0.18 and 0.28 oz). The fur and wing membranes are light brown in color, and the bat lacks the dark shoulder spots found in the closely related, and otherwise similar Keen's myotis. Compared to other Myotis species, these bats have long ears with a relatively long tragus; when folded forwards the ears extend well past the nose. They also have a longer tail and larger wing area than most comparably sized Myotis bats, giving them increased maneuvrability during slow flight.
Biology and behavior 7
During the spring and summer, northern long-eared bats spend the day roosting in trees or artificial structures, switching to a new roost every other day on average. Roost trees tend to be close together, and within about 600 m (2,000 ft) of areas suitable for foraging. Males and non-reproductive females roost singly or in small groups, but reproductive females and their young form much larger maternity colonies, with up to sixty individuals.
In the fall, northern long-eared bats migrate to caves to hibernate. Depending on the latitude, this may occur at any time between September and November, and the bats emerge between March and May. They typically hibernate together with much larger numbers of bats of other species, although hibernating groups of northern long-eared bats may still number in the hundreds.
Northern long-eared bats are well-suited to foraging in the forest interior. Their echolocation calls have a classic frequency-modulated structure that allows these bats to navigate through cluttered environments, although they are shorter, quieter, and higher pitch (126 to 60 kHz) than those of other Myotis bats. Their diets are focused on moths, although they also eat beetles, flies, and other insects. Unusually, they capture these by gleaning, or plucking, the insects from a surface, rather than capturing them in flight. They forage under the forest canopy or in spaces at the edge of forests, and most foraging occurs in the first two hours after sunset.
Mating occurs between July and early October, although the females probably store the sperm over the winter, and only become pregnant in the spring. The young are born between May and early July, depending on latitude, and are typically fully grown by the end of August. They have been recorded to live for over eighteen years in the wild.
Sources and Credits
- (c) U.S. Fish and Wildlife Service Headquarters, some rights reserved (CC BY), http://www.flickr.com/photos/50838842@N06/5881232758
- (c) Jason Whittle, some rights reserved (CC BY-NC-ND), uploaded by Jason Whittle
- (c) Brian Wulker, some rights reserved (CC BY-NC), http://www.flickr.com/photos/bdwulker/9793560966/
- (c) Brian Wulker, some rights reserved (CC BY-NC), http://www.flickr.com/photos/bdwulker/9793521955/
- (c) U.S. Fish and Wildlife Service Headquarters, some rights reserved (CC BY), http://commons.wikimedia.org/wiki/File:Northern_long-eared_bat_with_visible_symptoms_of_WNS_(8509677139).jpg
- Adapted by floracliff from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Myotis_septentrionalis
- (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Northern_long-eared_bat_(myotis)
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