Barn Owls

On Friday (2023-07-07) my granddaughter and I saw two barn owls in a large pine tree. There were three nests - one was about 2-3 times the size of the others. A juvenile was next to the largest nest staring down at us. We briefly saw an adult flap its wings and then settle down into one of the smaller nests. Unfortunately, I didn't have my camera that day, so we went back on Wednesday (2023-07-12). We didn't see the owls, but evidence of their presence was there: bird droppings on the sidewalk, many feathers and we counted 9 owl pellets.

Posted on July 14, 2023 12:44 PM by truthseqr truthseqr

Observations

Photos / Sounds

What

Barn Owl (Tyto alba)

Observer

truthseqr

Date

July 12, 2023 03:50 PM PDT

Description

Barn Owl Pellet #A-01

Location: (Site-A) Found under the pine tree where this owl roosts:
https://www.inaturalist.org/observations/173672073

Pellet length: not measured
Pellet age: Unknown
Dissected? Yes

This pellet contained the remains of two species:

  1. (Botta’s Pocket Gopher) https://www.inaturalist.org/observations/172690847
  2. (North American Deer Mice) https://www.inaturalist.org/observations/172945757

Photos / Sounds

What

Barn Owl (Tyto alba)

Observer

truthseqr

Date

July 12, 2023 03:58 PM PDT

Description

Barn Owl Pellet #A-02

Location: (Site-A) Found under the pine tree where this owl roosts:
https://www.inaturalist.org/observations/173672073

Pellet length: not measured
Pellet age: Unknown
Dissected? Yes

This pellet contained the remains of two species:

  1. (California Vole) https://www.inaturalist.org/observations/172692463
  2. (Western Harvest Mouse) https://www.inaturalist.org/observations/173788479

Photos / Sounds

What

Barn Owl (Tyto alba)

Observer

truthseqr

Date

July 12, 2023 04:11 PM PDT

Description

Barn Owl Pellet #A-03

Location: (Site-A) Found under the pine tree where this owl roosts:
https://www.inaturalist.org/observations/173672073

Pellet length: not measured
Pellet age: Unknown
Dissected? Yes

This pellet contained the remains of two species:

  1. (Botta’s Pocket Gopher) https://www.inaturalist.org/observations/172691120
  2. (California Vole) https://www.inaturalist.org/observations/172833851

Photos / Sounds

What

Barn Owl (Tyto alba)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Barn Owl Pellet #A-04

Location: (Site-A) Found under the pine tree where this owl roosts:
https://www.inaturalist.org/observations/173672073

Pellet length: not measured
Pellet age: Unknown
Dissected? Yes

This pellet contained the remains of two species:

  1. (North American Deer Mice x2) https://www.inaturalist.org/observations/172693506
  2. (Western Harvest Mouse x2) https://www.inaturalist.org/observations/172999960

Photos / Sounds

What

Botta's Pocket Gopher (Thomomys bottae)

Observer

truthseqr

Date

July 12, 2023 03:50 PM PDT

Description

Bones found in barn owl pellet #A-01.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/172677883

Photos / Sounds

What

Botta's Pocket Gopher (Thomomys bottae)

Observer

truthseqr

Date

July 12, 2023 04:11 PM PDT

Description

Bones found in barn owl pellet #A-03.

Here's the observation for the pellet itself:
https://www.inaturalist.org/observations/172690619

References:
• Entire skeleton: https://www.reptileevolution.com/heterocephalus.htm
• Skull & maxilla, teeth & habits: https://www.utep.edu/leb/PleistNM/taxaMamm/Geomyidae.htm
• Long bones & scapula: https://freyjasforest.com/products/pocket-gopher-bone-lot
• iNaturalist Taxa Info: https://www.inaturalist.org/taxa/44062-Thomomys-bottae

Photos / Sounds

What

California Vole (Microtus californicus)

Observer

truthseqr

Date

July 12, 2023 03:58 PM PDT

Description

Bones from barn owl pellet #A-02.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/172677889

Photos / Sounds

What

North American Deer Mice (Genus Peromyscus)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Bones from barn owl pellet #A-04.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/172690620

Photos / Sounds

What

California Vole (Microtus californicus)

Observer

truthseqr

Date

July 12, 2023 04:11 PM PDT

Description

Bones found in barn owl pellet #A-03.

Here's the observation for the pellet itself:
https://www.inaturalist.org/observations/172690619

Photos / Sounds

What

Western Harvest Mouse (Reithrodontomys megalotis)

Observer

truthseqr

Date

July 12, 2023 04:11 PM PDT

Description

Bones from barn owl pellet #A-05.

This pellet was cut open before I got a photo of the pellet itself. Also, the images are blurry - we were getting tired, so we saved the rest of the pellets for another day.

Here's the observation for the pellet itself:
https://www.inaturalist.org/observations/182471277

Photos / Sounds

What

North American Deer Mice (Genus Peromyscus)

Observer

truthseqr

Date

July 12, 2023 03:50 PM PDT

Description

Bones found in barn owl pellet #A-01.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/172677883

Photos / Sounds

What

Western Harvest Mouse (Reithrodontomys megalotis)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Bones from barn owl pellet #A-04.

Note the grooved upper incisors.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/172690620

Note: in photo #6, only the smaller 2 skulls and mandibles are from harvest mice, the larger skull is from a Peromyscus.

Photos / Sounds

What

Barn Owl (Tyto alba)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Barn Owl Pellet #A-06

Location: (Site-A) Found under the pine tree where this owl roosts:
https://www.inaturalist.org/observations/173672073

Pellet length: not measured
Pellet age: Unknown
Dissected? Yes

This pellet contained the remains of:
(California Vole) https://www.inaturalist.org/observations/173012330

Photos / Sounds

What

California Vole (Microtus californicus)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Bones from barn owl pellet #A-06.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/173011365

Photos / Sounds

What

Barn Owl (Tyto alba)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Barn Owl Pellet #A-07

Location: (Site-A) Found under the pine tree where this owl roosts:
https://www.inaturalist.org/observations/173672073

Pellet length: not measured
Pellet age: Unknown
Dissected? Yes

This pellet contained the remains of:
(California Vole) https://www.inaturalist.org/observations/173016933

Photos / Sounds

What

California Vole (Microtus californicus)

Observer

truthseqr

Date

July 12, 2023 04:28 PM PDT

Description

Bones from barn owl pellet #A-07.

Here is the observation for the pellet itself:
https://www.inaturalist.org/observations/173016050

Photos / Sounds

What

North American Deer Mice (Genus Peromyscus)

Observer

truthseqr

Date

July 12, 2023 04:11 PM PDT

Description

Bones from barn owl pellet #A-05.

This pellet was cut open before I got a photo of the pellet itself. Also, the images are blurry - we were getting tired, so we saved the last 3 pellets for another day.

Here's the observation for the pellet itself:
https://www.inaturalist.org/observations/182471277

Comments

Posted by truthseqr 9 months ago

Totally cool!

Posted by biohexx1 9 months ago

Cool! I've been doing something similar with a great horned owl at a nearby park: https://www.inaturalist.org/projects/tamanend-great-horned-owl-diet/journal.

Posted by brennafarrell 9 months ago

Wow, @brennafarrell !!! Your project is so awesome and interesting. I love how you compiled the data so it's easy to see what the owls eat over time. You've inspired me to continue monitoring these barn owls.

Posted by truthseqr 9 months ago

Thanks so much! Since I had so many observations at the park, I decided to make a project to easily find the observations. I can also export the data as a .csv, allowing me to easily make graphs and charts in Excel.
Good luck! Hopefully they'll give you lots of pellets to dissect.

Posted by brennafarrell 9 months ago

Add a Comment

Sign In or Sign Up to add comments

Gracias al apoyo de:

¿Quiere apoyarnos? Pregúntenos cómo escribiendo a snib.guatemala@gmail.com