Snapshots of Snapshot Day

Since 2000 the first Saturday in May is Snapshot Day in Santa Cruz. This is a big event where the Coastal Watershed Council trains groups of citizen scientists to collect water quality data on the streams and rivers that drain into the Monterey Bay National Marine Sanctuary, then sets them loose with a bucket of gear, maps, and data sheets. The result is a “snapshot” of the health of the watershed. As we did last year, my students and I were among the volunteers who got to go out yesterday and play in coastal streams. This year there were 13 (+1) groups sent out to monitor ~40 sites within Santa Cruz County. For reasons I don’t entirely understand four sites in San Mateo County (the county to the north along the coast) were included in this year’s sampling scheme; hence the +1 designation. Since I routinely haunt the intertidal in this region I took the opportunity to become more familiar with the upstream parts of the county and volunteered to sample at these northern sites. It just so happened that I was teamed with two of my students, Eve and Belle, for yesterday’s activities.

Of our four sites, two were right on the beach and two were up in the mountains. Thus our “snapshots” covered both beach and redwood forest habitats. Here are Belle and Eve at our first site, Gazos Creek where it flows onto the beach:

After heavy rains the water draining through the watershed breaks through the sand bar and the creek flows into the ocean. Yesterday the sand bar was thick and impenetrable, at least to the measly amount of rain we’d had in the past 24 hours.

At each site we collected two water samples, for nutrient and bacteria analyses, and the following field measurements:

• air and water temperature
• electrical conductivity
• pH
• dissolved oxygen (DO)
• water transparency

Here Eve is measuring conductivity in Gazos Creek (beach site):

Most of the equipment we used to take the field measurements was simple and straightforward: pH strips and a thermometer, for example. Even the conductivity meter was easy to use. You just turn it on, let the machine zero out, and stick it in the creek facing upstream so that water flows into the space between the electrodes. Here’s Belle taking a conductivity measurement at our Gazos Creek (forest) site:

The only tricky field measurement was the one for dissolved oxygen (DO). This involved collecting a water sample (easy enough), inserting an ampoule containing a reactive chemical into the sample tube, breaking off the tip of the ampoule so that water flows into the tube, and gently mixing the contents of the ampoule for two minutes. Then you compare the color of the ampoule with a set of standards in the kit to estimate the DO level in mg/L (=ppm).

Our second and third sites were up in the mountains, at Old Woman’s Creek and Gazos Creek (forest). With all the rain we had over the winter the riparian foliage has exploded into green. It was all absolutely lush and glorious. How lucky we were to spend the day in such surroundings!

And there were a great many banana slugs! All of them were solid yellow, with no brown spots. At one point there were so many slugs that we had to be extremely careful not to step on them.

Our fourth and final site was Whitehouse Creek, which flows into the Pacific Ocean to the south of Franklin Point. We had about a 10-minute hike to the creek from the road. By that point it had been raining for quite a while. Although we were protected from the rain by the trees when we were up in the forest, when we walked out to the field to the beach we were lucky it had eased to a light sprinkle.

After we finished our sampling we all agreed that we had to have gotten the most picturesque sites. None of the other teams got to visit both forest and beach for their sampling! We didn’t drop off our samples and equipment until 14:00, a couple of hours later than the other groups, but who would complain about having getting to spend the day tromping through the forest AND the beach?