12 March 2011

To See The Forest And The Trees

A couple of weeks ago, I was in Michigan to do a forest and Indiana Bat (Myotis sodalis) habitat assessment. Below are some photos of trees that are potential summer roost trees for this Federally Endangered species.


With a high percentage of exfoliating bark, Shagbark Hickory (Carya ovata) is the poster child for Indiana Bat roost trees.


Live or dead/dying trees with peeling bark are considered potential habitat for Indiana Bat. In addition to Shagbark Hickory and other hickories (Carya spp.), oaks (Quercus spp.), maples (Acer spp.), Eastern Cottonwood (Populus deltoides), and ashes (Fraxinus spp.) are the most common Indiana Bat summer roost trees. The White Oak (Quercus alba) shown above was greater than 3 feet in diameter at breast height (DBH), had peeling bark and hollow branches, and was located in a landscape position that would allow for roosting bats to access a clutter-free creek corridor. Aside from the fairly dense subcanopy in the immediate vicinity, this tree would make a good bat roost.


The White Oaks shown above and below are also potential Indiana Bat roost trees. All three of these were enormous, old, open-grown trees.


Overall at this site, we saw more than 40 trees greater than 25 inches DBH that were potential Indiana Bat roost trees. In addition, bat foraging habitat and connectivity were present, so it is likely that the next step will be for our bat biologist to set up mist nets and try to capture bats to see exactly what species are present.

5 comments:

Mike Whittemore said...
This comment has been removed by the author.
Mike Whittemore said...

I love being surprised in the middle of the woods by a great big ol' wolf tree amid younger-growth trees. They provide such great nostalgia and context to the land!

I had a chance to do some volunteer work with bats this fall. The one night I couldn't make it, my crew ended up netting an Indiana bat! I'm hearing there is growing concern for the little brown bat as well. Hopefully we can find a cause and solution for WNS soon!

Scott Namestnik said...

Thanks for the comment, M. Yes, White-nose Syndrome sounds very bad. Our bat biologist at work paints a pretty negative picture. As you said, Little Brown Bat is supposed to take a huge hit from the fungus (or whatever it is); pretty much all bats that have hibernacula in caves are at risk. WNS is now documented in Indiana, as far north as Bloomington.

Heather Holm said...

Interesting article Scott. Is the Shagbark native to just the southern part of Michigan? It's only along the southest MIssissippi River counties in MN.

Scott Namestnik said...

Thanks Heather. Yes, Shagbark Hickory is native throughout much of the southern half of the lower peninsula of Michigan. See http://www.bonap.org/BONAPmaps2010/Carya.html for a full description of its North American range. On these maps, dark green shows the states in which the species are native, and light green shows counties in which the species are present and not rare.