Wildlife Clinic

Species

Northern yellow bat

Lasiurus intermedius

A large yellowish bat of southern coasts that roosts in the dead fronds of palms and in Spanish moss.

A yellowish northern yellow bat tucked into the fold of a palm frond, its face turned to the camera.

Photo birdingbunny (opens in a new tab) / iNaturalist, CC BY-NC 4.0 (opens in a new tab)

At a glance

Size
Body about 12 to 14 cm; wingspan about 35 to 40 cm
Weight
About 14 to 31 g
Habitat
Coastal plain woodlands, palm stands, live oak hammocks and wooded neighbourhoods
Diet
Flying insects, including flies, mosquitoes, beetles and moths
Active
Night, and year-round in the Deep South
Roost
Hanging clumps of Spanish moss and the dead-frond "skirts" of palms
Young
Usually two to four pups
Rabies vector
Yes

Identification

Key marks
Large; long yellowish-brown to greyish fur; furred only on the front half of the tail membrane
Told apart from
Seminole and eastern red bats, which are red and smaller
Told apart from
Big brown bat, which is darker brown with black wings and ears and a bare tail membrane
Where to look
Palm skirts and Spanish moss in coastal Georgia and Florida; hunting over open ground, golf courses and wetlands at dusk

Behaviour

Northern yellow bats live near the coast in the Southeast, where they roost in Spanish moss and among the dead fronds that hang below the crowns of palms. Several bats may use the same clump of moss or palm skirt, and females gather in small maternity groups in summer.

They hunt over open areas: marsh edges, fields, lawns, golf courses and the edges of woods, often flying 5 to 15 metres up. They do not hibernate, but slow down on cold nights and feed whenever it is warm enough for insects.

Why they matter

Their hunting grounds — open land at the edge of towns — are exactly where mosquitoes and other biting flies swarm at dusk, and flies are a regular part of their diet.

They also tie a bat's life to a single plant feature: the dead palm skirt. Where ornamental palms are trimmed clean, northern yellow bats lose roosts they cannot easily replace.

Reproduction and lifecycle

Mating — autumn and winter
Birth — May and June, usually two to four pups
Nursing — pups stay in the roost while their mother feeds
Flight — at about four weeks old
Independence — by mid-summer
Lifespan — not well recorded in the wild

Living around people

  • Trimming the dead fronds from palms between April and August can kill pups in the skirt; leave skirts in place or trim in winter.
  • Removing Spanish moss takes away roosts.
  • Cats and outdoor lighting near roosts disturb these bats.
  • A yellow bat on the ground should never be picked up with bare hands; bats are rabies vector species.

Misconceptions

  • Dead palm fronds are only a fire and pest hazard. They are a nursery for yellow bats; trimming them in summer can kill a litter.
  • Bats come to towns to bother people. They come for the insects that gather over lawns and water at dusk.
  • All bats roost in caves or attics. This one lives in palms and moss.

Related species

Seasonal activity

When this species is breeding, and when there are nests on the ground. Mowing during the shaded months is how most nests are found.

Breeding and active nests by month for this species
JanFebMarAprMayJunJulAugSepOctNovDec
BreedingJan: noFeb: noMar: noApr: noMay: noJun: noJul: noAug: noSep: noOct: noNov: noDec: no
Active nestsJan: noFeb: noMar: noApr: noMay: noJun: noJul: noAug: noSep: noOct: noNov: noDec: no
NotesActive on warm evenings; quiet through cold spellsFemales pregnant; foraging increases with warmer nightsActivity risesFemales gather in maternity groups in moss and palm skirtsPups are born, usually two to fourMothers nurse pups in the roost and hunt at nightYoung begin to flyYoung are independentMating is thought to beginActive on most eveningsMating continues; activity eases in cool weatherActive on mild nights

Where it lives

Recorded in 20 states and provinces. Each one links to the other animals there, and to the rehabilitators licensed for them.

Treated as a rabies-vector species in Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Texas, Chiapas, Colima, Guerrero, Jalisco, Nayarit, Nuevo Leon, Oaxaca, Puebla, Tabasco, Tamaulipas, Veracruz and Yucatan. There, only a certified rehabilitator may take one.

If you found one

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