June 2000 PRBO Riparian Songbird Study Post-fire
Observations Along Lee Vining Creek
E-mail message dated June 3, 2000
Hello everyone,
I just completed one of our point count transects in Lee Vining
Canyon, and thought you might be interested in some post-fire
observations. For those of you that don't have the background, the
southern moraine of Lee Vining Canyon and some of the southern creek
edge caught fire last monday May 29. The fire started across the creek
from Asuza campground, by an illegal campfire.... or so the last story
I've heard goes.
Six of our point count stations were burned. With the use of a GPS
and written descriptions, I had no trouble finding the points. The 50m
radius circle around each of these points ranged from 40% to 50%
burned... in every case, the northern side of Lee Vining Creek is
intact and the southern side of the creek is charred down to the sandy
soil. So, the 60%-50% unburned portion of the point count circle
reflects the north side of the creek, and the few remaining trees in
the burned portion. A few green lodgepole or Jeffrey pines remain
within the burned portion at each point and some 1/2 burned willow,
but for the most part the burned landscape consists of white and black
ashy ground spotted with blackened and burned lodgepole, Jeffrey and
aspen snags and close-to the ground blackened and burned willow
stumps.
Most of the bird species detected at this site (all points, not
just burned ones) during the past two seasons were species whose nests
are generally found in the mid to upper canopies of Jeffrey and
lodgepole pines and aspens: species such as Western Wood Pewee,
Western Tanager, Audubon's Warblers, Cassin's Finch, Warbling Vireo,
Brown Creeper, American Robin and Steller's Jays. Cavity nesters :
Hairy Woodpecker, Red-breasted Sapsucker, House Wren, Tree and Violet
Green Swallows, and Mountain Chickadee. Five species of sometimes low
canopy, but predominantly shrub-nesting birds such as Black-headed
Grosbeaks, Brewer's Blackbird, Song Sparrows, Green-tailed Towhees and
Yellow Warblers were were also encountered as breeders in previous
years. Two species of ground nesters, Oregon Junco and Spotted Towhee
bred at this site 1998 and 1999.
During today's count, I detected all of the above species. I
observed a pair of Oregon Juncos and Western Wood Pewees perching and
flitting about the charred branches of the lodgepoles, acting
territorial, but unseasonably not "nesty". A Cassin's Finch
was carrying nesting material. Tree Swallow eggs were observed near
this site 2 weeks ago, so I'm guessing some nests were lost during egg
stage.
I look forward to monitoring this site in the future, and wonder if
we will detect any changes in species composition or abundance in this
post-fire recovering landscape.
All my best,
Sacha
Sacha Heath
Point Reyes Bird Observatory
(415) 868-0655 - Phone
(415) 868-1221 X 777 - Voice Mail
(415) 868-9363 - Fax
sheath@prbo.org - email
4990 Shoreline Hwy.
Stinson Beach, CA 94970
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