Here are D.'s pics from the Weep.
We gather at the Alviso marina before heading out on the levee.
Microbiologist Wayne shows us on a blown-up aerial photograph of the area where we'll be going.
Microbiologist Wayne begins setting up the first field microscope when we arrive at the Weep.
Our group at the Weep.
Microbiologist Wayne takes a small sample of water from the Weep to check its salinity.
It was over twice that of seawater.
Alex takes another sample in order to confirm Wayne's reading.
The edge of the Weep, where the water peters out.
A feather floats in the shallow water, barely one inch deep.
The field microscope is set up and ready to go.
Wayne attaches a light source for better viewing.
Our first slide is mounted and ready to view the microscopic critters.
Looking north from the Weep.
Looking south, toward the Environmental Education Center at the Don Edwards San Francisco Bay National Wildlife Refuge.
A clump of dead pickleweed.
Wayne prepares to scoop up a sample from the far side of the Weep using a collecting cup clipped to the end of his hiking staff.
We take turns peering at the tiny critters in the microscope.
The train tracks run on forever into the distance.
On the far side of the Weep alongside the train tracks, we collect sample of the alga Codium, whose population fluctuates wildly depending on how much fresh water seeps in from the other side of the tracks.
Wayne explains the biology of Codium.
A lot of gunky-looking stuff grows in the Weep.
But that's a good thing. The cyanobacteria that live here create the oxygen we breathe. The greatest concentrated weight of oxygen producers is found in wetlands, particularly in salt marshes. Every fifth breath you take was made possible by a cyanobacterium called Prochlorococcus, which grows abundantly here. By biomass, it's the world's most plentiful organism.
Thick mats of cyanobacteria flourish in this rill flowing into the Weep.
Not very appetizing-looking, but it helps keep us alive and breathing.
A crust of salt begins to develop at the edge of the salt pond across the levee from the Weep. Its salinity is several times that of seawater.