David Mateus1, Vasco Martins1, Luis Morais1, Francisco Neves1, Stephen Hawkins2,3,4, Andrew Altieri5,6, José Paula7, Teresa Cruz1
1University of Évora, Portugal - 2University of Southampton, UK - 3Marine Biological Association of the UK, UK - 4University of Plymouth, UK - 5Smithsonian Tropical Research Institute, Republic of Panama - 6University of Florida, USA - 7University of Lisbon, Portugal
The stalked barnacle Pollicipes pollicipes is a foundation species that creates an important microhabitat and contributes to reef-associated biodiversity. This species inhabits intertidal and shallow subtidal very wave-exposed rocky shores from SW England to Senegal. It is gregarious and forms clumps of different sizes. The small-scale variation in clump size might influence the diversity of associated fauna. Given that P. pollicipes is heavily harvested throughout its distribution, such harvesting might impact the size of the clumps and thereby potentially affecting the diversity of the associated fauna. We expect that sites more protected from harvesting will have larger clumps than those more exploited, and that the diversity associated with different-sized clumps may vary. To test these hypotheses, we conducted a study in September 2024 in Peniche (considered a highly exploited region) and Berlengas Nature Reserve (RNB, a small archipelago 9.2 km from Peniche, considered a less exploited region due to specific regulations for harvesting this species). Two sites were sampled in Peniche and four sites in RNB. The individual size of the clumps and the percentage cover of P. pollicipes in each site were estimated by image analysis (photos of 50x50 cm quadrats (n=10), QGIS software). To study the effect of clump size on the associated fauna, 5x5 cm quadrats dominated by P. pollicipes (n=6) were scraped off within clumps of different sizes: small ( 20-40 cm2), medium ( 70-110 cm2), and large ( 110-140 cm2). Sediment and associated fauna were weighed and the associated fauna is being identified to the lowest possible taxonomic level. Additionally, we have measured several predictive variables: biomass, number and size (maximum rostro-carina length and maximum height) of P. pollicipes. Preliminary results indicate a higher biomass of P. pollicipes collected at RNB, as well as bigger clumps and percentage cover.
Biography
David Mateus is a PhD student at the University of Évora (Portugal) and MARE. His research focuses on the ecology of rocky shores, with an emphasis on understanding the physical and biological processes that influence the diversity, distribution, and abundance of species. David is studying the patterns and processes of habitat-forming species, such as mussels and stalked barnacles, to better comprehend their roles as foundation species and the importance for reef-associated biodiversity.