Written by Laila Rosenthal, WM Undergrad
We began our day working on identifying previously collected organisms in the lab at the School of Ocean Sciences. Our species list is continuously growing; we have identified around 50 species, many of which are similar to those we see at home but slightly different. For example, the dominant low marsh species at home is Spartina alterniflora, while the dominant species here is Spartina townsendii (be sure to ask Daniel Rowen and Jim Perry about the biogeography of Spartina when you get a chance).
Speaking of marshes, we also spent time today analyzing the density and percent cover data that we collected for low and high marsh sites at Newborough Warren & Ynys Llanddwyn National Nature Reserve. The raw data that we collected allowed us to calculate a parameter called Relative Importance. As the name implies, this assigns a value to each species based on how abundant they are and how much area they cover. The final analysis and discussion of this data will be presented by one student for their final presentation.
After lab, we all piled into the vans and headed to the tide pools at Cemlyn Bay. The drive was a bit long, but the trip was definitely worth it because these tide pools were much larger, deeper, and clearer than those at Shell Island. The weather actually cleared up for almost the entire time, so we had all had a great time climbing over the rocks that were exposed at low tide.
Cemlyn Bay is a unique habitat because it includes one rocky shore that is exposed to high energy (left) waves and one that is very protected (right). The impact of energy on the biology of the system was very evident from the get-go. The high energy habitat could be described as rocky and barren; we found barnacles covering many of the lower rocks and other organisms nestled in crevices. At the protected shore, however, all rocks were densely covered in macroalgae. We had to flip back mats of Ascophyllum and Fucus to find organisms of interest; furthermore, there was very little free space on rocks where barnacles could settle. Once again, we collected height, width, and aperature measurements on a selection of dogwhelks from each site in order to make statistical comparisons between two separated populations.
The photos above show some of the algae species that we found in the tidepools on the exposed site. The diversity is incredible, and we are trying to identify as much as possible. We collected more specimens from Cemlyn Bay to bring back to the lab and keep in aquaria.
We eventually had to leave because rain was blowing in from offshore, but we were able to stop at a little tourist station for snacks. The owner was initially slightly appalled at our bedraggled appearance, but after asking that we remove our slightly soaked shoes (due to a few slips into tide pools), she served us a proper English tea, complete with scones, homemade jam, and clotted cream.