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Pt. Molate and Bat Question


Jim Chiropolos
 

Ann Griffith and I kayaked from Pt. Molate harbor to the red brick former winery building. I was surprised to find an ell grass bed in the cove to the west of the red brick winery - birders should look for Brandt in the future here. The most interesting spotting was a harbor porpoise in the channel between east brother island. I was surprised to see a porpoise this deep into the bay! Common species seen with very few cormorants and pelicans on the paddle.

I have been watching at least two species of bats just before dusk by my house. The most common one is very small, maybe about the size of a least goldfinch with a very erratic flight typically within 20 feet of the ground. I have an idea of what species it is but how do people identify bats with reliability in the air? A second species flies higher with not as many changes of direction and is maybe 50 percent bigger. Both these species are being seen in "openish or open woodland type areas. Any sound advice would be appreciated.

Jim Chiropolos , Orinda


Bev
 

The bat "eratic" flight is deliberate because they are hunting for insects and can make rapid turns and corrections as they hunt.  Being in the open is safer for them and likely where insects are, just like how Western Bluebirds hunt for insects in the open. Not sure about species though. Faces and noses can tell a lot. I'm guessing all bats in the Bay Area are insectivores and echolocate.

Bev


-----Original Message-----
From: Jim Chiropolos <jnc@...>
To: EBB-Sightings@groups.io
Sent: Mon, Sep 7, 2020 8:14 pm
Subject: [EBB-Sightings] Pt. Molate and Bat Question

Ann Griffith and I kayaked from Pt. Molate harbor to the red brick former winery building. I was surprised to find an ell grass bed in the cove to the west of the red brick winery - birders should look for Brandt in the future here. The most interesting spotting was a harbor porpoise in the channel between east brother island. I was surprised to see a porpoise this deep into the bay! Common species seen with very few cormorants and pelicans on the paddle.

I have been watching at least two species of bats just before dusk by my house. The most common one is very small, maybe about the size of a least goldfinch with a very erratic flight typically within 20 feet of the ground. I have an idea of what species it is but how do people identify bats with reliability in the air? A second species flies higher with not as many changes of direction and is maybe 50 percent bigger. Both these species are being seen in "openish or open woodland type areas. Any sound advice would be appreciated.

Jim Chiropolos , Orinda




Patricia Bacchetti
 

Jim,

There are a couple of apps that you can install that listen for bat sounds and give you the most likely species.  Wildlife Acoustics makes a rig That you can attach to your phone that is more accurate:   https://www.wildlifeacoustics.com/resources

When the pandemic ends, both Yolo Basin in Davis and the Middle Mountain Foundation at the Sutter Buttes have wonderful bat programs.  Yolo Basin has an amazing bat fly out from under the causeway, and apparently there are 3 peregrines picking the bats out of the air at dusk.  The Middle Mountain Bat Hike has a short bird walk before researchers mist net and ID the bats caught.  I think we saw 5-6 different species of bats the night that I went. 

Pat Bacchetti
Oakland


On Sep 7, 2020, at 8:15 PM, Jim Chiropolos <jnc@...> wrote:

Ann Griffith and I kayaked from Pt. Molate harbor to the red brick former winery building. I was surprised to find an ell grass bed in the cove to the west of the red brick winery - birders should look for Brandt in the future here. The most interesting spotting was a harbor porpoise in the channel between east brother island. I was surprised to see a porpoise this deep into the bay! Common species seen with very few cormorants and pelicans on the paddle.

I have been watching at least two species of bats just before dusk by my house. The most common one is very small, maybe about the size of a least goldfinch with a very erratic flight typically within 20 feet of the ground. I have an idea of what species it is but how do people identify bats with reliability in the air? A second species flies higher with not as many changes of direction and is maybe 50 percent bigger. Both these species are being seen in "openish or open woodland type areas. Any sound advice would be appreciated.

Jim Chiropolos , Orinda