Robert
Campbell flies his own Helio Courier aircraft, operates his
own custom color lab and has over 30 years experience as a
professional pilot and professional photographer. Custom color
prints, murals, transparencies, electronic files for publication,
courtroom exhibits preparation of photographs for use on the
Web and elegant website design, Robert Campbell / Chamois Moon
does it all.
Photographs: The
Cargill salt ponds are located in San Francisco Bay near
the cities of Newark, Redwood City and Napa. The Napa operation
was closed approximately ten years ago, and the ponds are
slowly reverting to a ‘natural’ state. Anyone
who has looked out the window of an airliner approaching
San Francisco International Airport on a clear day has seen
this multi-colored pallette in the South Bay. This is where
Leslie brand table salt is produced.
I
first noticed these ponds when I was learning to fly in the
mid 1960s. The geometric patterns provided good reference points
for practicing certain required aerial maneuvers. Several years
later, when I was studying photography at San Francisco State
College, I began photographing the ponds. I was fascinated
by the combination of the abstract and the real -- it was Diebencorn
with a drawbridge, Thiebaud with a transmission tower or Pollock
with a powerline
Over
the years, I spent many hours turning circles over the area
and have a large portfolio of salt pond images. The area is
constantly changing -- with the seasons; with the weather and
with the age of the ponds. Each time I visit the area, I discover
something new.
The
colors which fascinated me are created by algae, minerals,
micro-organisms and brine shrimp. Water is drawn out of the
ponds through natural evaporation, and during the five years
it takes for the bay water to mature into salt brine, it is
pumped from one evaporation pond to another. In the final stages,
when the brine is fully saturated, the remaining water is pumped
from the pond and a bed of salt 5 to 8 inches thick is ready
for harvest.
The
palette of colors that makes the salt ponds so beautiful is
created by a complex ecosystem. The colors range from pale
green through deep coral pink to bright red. The color indicates
the salinity of the ponds. Micro-organisms change their hues
as the salinity of the pond increases. In low to mid-salinity
ponds, green algae is predominant, giving the water a deep
greenish cast. As the salinity continues to build up, an algae
called Dunaliella shifts the color to a lighter shade of green.
In middle to high salinity ponds, the Dunaliella produces a
red pigment. Millions of tiny brine shrimp lend an orange cast
to the water in mid-salinity ponds. Salt loving bacteria such
as Stichococcus also contribute red tints to high salinity
brine.
These
ponds and the marshes that surround them are important habitat
for more than 70 species of birds, including several endangered
species. There is a proposal to return this area to a more
natural state as mitigation for the filling of part of San
Francisco bay for two new runways at San Francisco International
Airport.
