Cooking and biology both have their similarities. Add too much salt and you can overpower a meal; add too little and you risk blandness. It is quite the steep slope, and one must be very careful when dealing with salt as extreme salinities can have adverse effects on our taste buds, yuck! Similarly, salt levels play a significant role in biology as well; they can play a role in determining the performance, distribution, and abundance of different animal species as different animal levels can only tolerate certain salt levels. Now I am not sure how a barnacle tastes with salt, but what I am really interested in is how it can deal with low salt levels!
Our Barnacles of study
Photo credit Rohan Bhan
How we came about this study
Upon a visit to the Bamfield Marine Sciences Center our class had noticed that Bamfield housed many radical animals that were different than the ones in Vancouver, and we collected some for experimentation. Bamfield and Vancouver differ in their extreme minimum and average salinity; Bamfield has a much higher salinity than Vancouver. However, within each of these regions, there are also local site that vary in salinity. We wanted to understand the mechanism of barnacle performance at low salinity for both sites.
The Set Up
We set up three tanks filled with waters of different salinities that ranged from 12 ppt, 20 ppt, and 28 ppt. We had four sets of barnacles: high salinity Bamfield, low salinity Bamfield, high salinity Vancouver, and low salinity Vancouver.
The lab set up
Photo Credit: Rohan Bhan
The three tank setup
Photo credit: Harry Chu
What were we measuring?
To measure barnacle performance against different salinities, we measured the proportion of each barnacle feeding on a rock, the amount of times it extended its feeding appendage in a minute, and the average size of the three largest barnacles, and the number of juvenile barnacles. The first two barnacle characteristics mentioned are behavioral comparisons, and were compared against region, source local salinity, laboratory salinity, and a combination of these variables. The latter two are population characteristics and were compared against region, local salinity, and to see if they both had an interaction.
Professor Chris Harley doing his thing
Photo Credit: Rohan Bhan
What did we learn?
The take away message from our experiment was that low salinity causes stress to barnacles and may affect their performance characteristics differently depending on their region. For instance, we found that Vancouver subpopulations had higher proportion of barnacles feeding at low salinities compared to the subpopulations from Bamfield. This contrasted with population determiners of barnacle performance; we found that proportion of small barnacles were higher in the high local salinity, and did not depend on region!
For more Information on salnities effects on barnacle species here are some papers that may be informative: