Birds and Bats in Seattle Area

  • Birds and bats are winged pests that infest homes and cause a nuisance to people
  • Birds tend to perch on areas such as chimneys, trees, power lines, sign posts and can at times get inside the house
  • Bats are hand-winged flying mammals that have no relation to rodents
  • Most bat species do not invade buildings or homes

Common Species of Birds and Bats in Seattle Areas


  • Pigeons are very common around urban areas in Seattle.
  • They perch on different structures including ledges, beams, and sign posts in busy areas leaving their droppings in urban spaces.
  • Pigeons tend to poop on public spaces causing concerns due to the nature of the unsanitary nature of defecation.
  • Accumulated droppings develop fungi that causes a lung infection called histoplasmosis.

Little Brown Bats and Big Brown Bats

  • The little brown bats have a seven inch wingspan.
  • The wingspan for big brown bats is approximately twelve inches.
  • Both little and big brown bats have a similar appearance characterized by brown bodies with velvety texture and dark faces.
  • These bats feed on insects and roost in daytime in colonies within buildings.
  • They appear at dusk to feed and drink water
  • These bat species can consume insects half their weight and solely feed on moths and beetles
  • At birth, these bats are big and their growth is rapid enabling them to fly within seven to eight weeks
  • While raising the young ones, female bats form maternity colonies and roost together
  • The size of one colony varies, ranging from 30 bats to thousands depending on space
  • Little brown bats and big brown bats tend to mate in autumn and delay their fertilization till spring
  • The bats hibernate during winter depending on roost conditions

Nuisances Caused by Birds and Bats

  • The major cause of bird and bat nuisance results from their invasion into the himan space such as buildings and homes.
  • Bats particularly look for warm areas to raise the young ones.
  • Inside buildings, birds and bats generate a significant quantity of droppings as well as urine that produces a bad stench, corrodes wood and poses bio-hazardous risks.
  • When the numbers are large, bats can be noisy and tend to stay in one location for a long time when they find a good maternity roost.
  • Every new generation tends to go back to the same place and bats have a lifespan of 20 years
  • Due to their slow mortality rate, bat colony sizes tend to double effectively every year
  • Bats transmit rabies to people and it is advisable to avoid picking dead bats

Keeping Birds and Bats Away

  • Birds and Bats may be kept away naturally by utilizing removal or exclusion methods. With exclusion, a device that creates a one way exit is used.
  • This approach considers issues such as hibernation periods and weather particularly for bats.
  • Birds and bats may also be kept away by creating physical deterrents to prevent them from landing or roosting in certain places.
  • Severe infestations of birds and bats require expertise from pest control officers