Bat ID Help

Hi all. I have some bat ID’s I am hoping to get some help with. All of these pictures were taken here in Northern Pima Country AZ on our house. All pictures were taken in August or September the last couple years. I am pretty sure at least one is a Big Brown Bat but I think there is a Myotis or two here as well but I don’t know if there is a way to tell which one. Photo 2&3 and Photo 4&5 are of the same bat. I am really bad at bat IDs so any help is appreciated.

I also have a post coming on Rodent ID help, so you have that to look forward to 🙂




  • Manuel Ruedi

    Dear Alan, it seems to me that these are indeed Big brown bats, the grayer one being a young. Interestingly, the first pictured bat has a bed bug on its right forearm; same for the juvenile, on the left forearm.
    Good nights!

  • Alan D

    Hi Manuel. Thanks for the IDs. I was hoping I might have had more than the Big Brown Bat. But, at least now I know.

    Thanks again.


  • Jon Hall

    Hi Alan,

    I ran this past Fiona Reid too and together we think …

    It looks like the 1st, 2nd and last picture are all Big Browns. Not sure about the third which doesn’t look like a BB to me but you said it was the same animal as in the 2nd pic?

    The other bats look like either Canyon Bats or could be Western Small-footed Myotis (if they return try to get a good shot of the inside of the ear … the tragus (internal lobe) is a good way to tell species/genus apart



  • Alan D

    Hi Jon, thanks for the reply. The pictures display in reverse from how I uploaded them unfortunately. The 3rd picture is of a different bat from #2. I will try to get better pictures of the ears next time. We have bats that roost around the house just about every night but most are Pallid Bats. So, I will try to keep an eye out for other bats and get better pictures.

    Thanks for the ID help.


Leave a Reply