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We’re settling into life here at San Evaristo. We’ve been here for
three full days now and we’re getting to know the local floral and
fauna better and better. Our camp cook, Carolina Espinoza, is also
getting to know the ways of San Evaristo. Today, she traded some of our
fresh produce for fresh halibut by motoring over to a shrimp boat
harbored in the bay. Again, dinner was a delicious menu that everyone
looks forward to after a hard days work. After dinner, we gathered to
share our findings up until now and discuss the progress of each
research team.
Team Herp Update
Team Herp is reassembling, after Dustin Wood (SDNHM Herpetology
Collections Manager) and students from UABC returned home after the
first phase of the expedition. In their absence, myself, Robert Hill,
Tom Myers, and Milan Mitrovich are now actively surveying the
herpetofauna. Compared to Los Dolores, there is less abundance, but
this is possibly due to the drop in the temperature. There are numerous
Red-spotted toadlets (Bufo punctatus) in the washes, indicating that
they have taken advantage of the moisture brought on by the hurricanes
from two months ago by switching into a reproductive mode. Robert Hill
observed a third Striped Racer (Masticophis lateralis) on his hike to
Ojo de Venado. The records of the Striped Racer from here and Los
Dolores are significant distribution indicators and fill a sampling gap
from La Paz to Arroyo Santa Domingo, located north of Ciudad
Insurgentes. Also notable is that both Tom Myers and Milan Mitrovich
each found the Baja California Rattlesnake (Crotalus enyo), a species
that has yet to be sampled within the conservation corridor. Milan has
also set up a series of drift-net fences with pit-fall and box traps in
the arroyo south of San Evaristo and will be checking them daily. While
lower temperatures could play a role in the lower number of species
seen here, it could also be a factor of geographic location and
available natural resources. A detailed study of distributional
patterns will be conducted after we return to see if there is any
significance in how the biodiversity is spread throughout the region.
Team Bird Update
Team Bird rolled into idyllic San Evaristo in our 12-passenger van with
binoculars in hand and opened our mist-nets well before dawn on our
first morning here. The early start paid off beyond our wildest hopes,
as two Baja California Sur endemics, a Western Screech-Owl and an Elf
Owl, flew into the nets. The latter species is poorly represented in
museum collections, and this was the first Elf Owl that any of us had
seen on the Baja California peninsula. We filled out our hard-working
team with two talented students, Ian McGregor from the Universidad de
Guadalajara and Edith Suazo from CICESE in Ensenada, and the four of us
have been plying the arid washes south of town for three days now.
Other discoveries of special interest include Baja California endemic
subspecies of the Gila Woodpecker, Ladder-backed Woodpecker, Cactus
Wren, and California Gnatcatcher. More surprising than the species
we’ve found are the ones that seem to be missing from the San Evaristo
area. The Pyrrhuloxia, California Towhee, Brewer’s Sparrow, and
White-crowned Sparrow are typically "givens" in desert arroyos of Baja
California Sur, but we have yet to encounter them here, and some other
adaptable and widespread species are quite sparse. This could be viewed
in a disappointing light, but we find it interesting to ponder the
array of ecological factors that combine to limit the variety of
species capable of thriving in this unique desert environment.
Yesterday Phil and Ian finished working at midnight only to be up again
at five this morning. Thankfully, tonight is more sane, and we have
high hopes for the nets we’ve set in a new arroyo near our previous two
sites. We’re looking forward to making the most of our last full day of
field work in this gorgeous setting!
Team Botany Update
Team Botany has collected approximately 200 different specimens during
the expedition from various localities throughout the Agua Verde/Punta
Mechudo Conservation corridor. To date, we have compiled a flora for
this region that consists of more than 450 different vascular plant
taxa, of which at least 35 percent are endemic to Baja California Sur,
a relatively rich and unique region of the peninsula. In recent days,
the hiking effort to different localities in the area has exceeded the
collecting effort, but the documentation of various rare and
little-known plants has still yielded important discoveries. The long
and steep climb to the lake in Valle del Venado was very productive for
botanical exploration. For example, new populations of Eucnide tenella,
Euphorbia chersonesa, Chamaesyce trachysperma, Viguiera purissimae and
Celosia floribunda have extended the known distributional ranges of
these rather uncommon species to completely new areas of the peninsula.
Bradford Hollingsworth
Expedition Coordinator
and
Rob Hamilton from Team Bird
and
Jon Rebman from Team Botany
From San Evaristo base-camp at 11:45pm | 
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