Four easily accessible tidal zones await the curious explorer
Photos and blog by Barbara Swanson. For full-size images in blog, please see slide show below.
Exploring an area for wildlife with an expert is always a great way to learn, so I was fortunate to be part of a small group that included two retired marine biologists during a very low tide at Bird Rock in La Jolla. While this area may not be as well known as several other San Diego county tide pooling locations, it offered ample wildlife and limited crowds. Low tide was around 3:30 in the afternoon at minus 1.4 feet, allowing us up to 400 feet of access along the substrate from shore. It was a sunny day with good light for plentiful photography!
Public access to Bird Rock is located via stairsteps from the southwest terminus of Bird Rock Avenue three blocks west of the roundabout on La Jolla Boulevard, which passes through La Jolla South’s mercantile strip.
Many of the critters in the slide show below were initially found by the marine biologists with their local experience, allowing me to photograph many more of them than I could have done on my own. Also, by following the guide of our marine biologists, we were careful to disturb the animals as little as possible. This is very important for their survival. After all, how would I feel if my home were suddenly visited by strange aliens with giant lenses? I would be much better off if they didn’t tear me away from the little block I live on, then carelessly throw me back into some dangerous, unknown place with predators and little food.
In rocky areas, bounded by the lowest breakers of low tides and the high splashes of the high tides, there are four ecological zones which support various habitat niches. This whole region is called the intertidal zone and is located between the mean high water mark and the mean lowest low water line. The uppermost zone is the splash zone, which is above the high tide line but can become wet from waves. The next region is the high intertidal zone, which is covered during high tide but dry for the rest of the tidal cycle. The animals that inhabit this region are able to withstand crashing waves, hours of limited water and temperature extremes. The middle intertidal zone is lower and is cyclically wet and dry during the tidal cycle. The low intertidal zone is only exposed during very low tides, such as what we experienced during our outing. Because of the very low tide, we were able to explore all of the described intertidal zones and find representative species in each region.
I used a 105 mm macro lens (1:1) for all of the marine photographs and used autofocus. A polarizing filter may have helped with glare in some circumstances, but it also reduces the light getting into the camera. As this was a very low tide and a calm day, there was no chance of getting splashed by waves where we were exploring. I carried extra batteries and cleaning supplies in a backpack, and used watertight plastic bags for the batteries and my phone just in case I fell into a pool of water. I wore surf footwear with some tread on it, as the rocks and seagrass were very slippery, and rolled up my quick-dry pants. Having the right clothing and equipment made the outing safe and enjoyable — Barbara Swanson.
SLIDESHOW BELOW: SOME FAVORITES FROM THE TIDE POOLS
Click on any image or its arrow ⇒ button lower right for enhanced views of the photos. Photos by Barbara Swanson.