BARNACLES LIVING IN SALTON SEA OF SOUTHERN CALIFORNIA

The present-day, man-made Salton Sea is one of the few saline lakes in the world with a population of barnacles; namely, Balanus amphitrite saltonensis Rogers, 1949.

Google Earth (2023) view of southern California and adjacent northern Mexico/Gulf of California.

Because of tectonic uplift associated with the early San Andreas Fault, the Salton Sea region was a low-lying region non-marine region. During the Pliocene and Pleistocene, the Salton Sea region was covered by shallow-marine waters. In 1905, when a man-made irrigation canal was being built in order to divert waters from the Colorado River into the Imperial Valley, an agricultural region in southeastern most California, there was a breach in the canal. The waters flowed for a considerable time into the adjacent, low-lying Salton trough. The end result was the creation of large lake, called “Salton Sea.” This lake is 226 feet (69 m) below sea level. It is approximately 35 miles long, 15 miles wide, and up to 37 feet deep. Water cannot flow out of it. This water is continually getting saltier over time. It is now 30 percent saltier than the Pacific Ocean.

The marine barnacles, which are Balanus amphitrite, reached the Salton Sea by hitch-hiking on the bottoms of Navy seaplanes. These planes were moored in the shallows of the on Pacific Ocean waters near San Diego. During flying-practice manuvers in 1943 for 1944, these planes would fly to the Salton Sea and practice landing on the water surface. Any of the Pacific Ocean barnacles that fell off the platoons along the bottoms of the planes into Salton Sea would have found a new home in these newly created salty waters. Over time, this geographically isolated population evolved into a new subspecies: B. amphitrite saltonensis. I mentioned these barnacles in one of my blogs (Nov. 11, 2017), entitled “Barnacles make interesting fossils.” 

Dorsal view of a small colony (3 cm long x 2 cm wide) of B. a. saltonensis from the Salton Sea.

All the following pictures were taken by me in Oct. 1984 in the vicinity of the headquarters of the Salton Sea Visitors Center, located in the northeast section of Salton Sea. The beaches there can have barnacle reefs, as well as storm-derived remains of the barnacle shells (and fish bones) that washed up and litter the shoreline in places. As shown below, the barnacles live just offshore, attached to plants and stones, as well as to each other. 

Attached barnacles forming a barnacle-reef at the shoreline.

Barnacles encrusting rocks along the shoreline.

Barnacles growing on partially submerged plants along the shoreline.

Wave-deposited accumulations of barnacles at the upper part of a beach.

One of the “take-home” lessons for geologists by visiting this area is the following: just because you might find barnacles in ancient sediments, do not assume, by default, that these sediments have to be marine in origin!