picture

Intertidal mollusks are subjected to an intense environmental pressure, from human-induced stressors, mainly harvesting, to competition for food and space with other species. A long-term comparison (1994-2014) of limpet size has been conducted as a surrogate of the state of conservation of these two limpets. Both species showed populations dominated largely by small-sized individuals (<30 mm) and a lack of large adults (>60 mm). The proximity to coastal settlements was not a factor to explain limpet assemblage structure. The temporal (1994e2014) comparative study showed a sharp decrease in the mean size of both limpet species (7 mm in P. aspera and 5 mm in P. candei crenata). Riera, R., O. Pérez, O. Álvarez, D. Simón, D. Díaz, O. Monterroso & J. Núñez. 2015. Clear regression of harvested intertidal mollusks. A 20-year (1994-2014) comparative study. Marine Environmental Research, 113. 56-61.

picture

Distributional shifts of marine species have recently received attention as a result of increasing man-induced pressures on coastal ecosystems and global climate change (i.e. ocean warming). The southernmost geographical limit of the fucoid Fucus guiryi is the Canarian archipelago where this species is currently forming scarce and low-dense populations. Studies on long-term herbarium data revealed the decrease in size of morphological features. More details in: Riera, R., C. Sangil & M. Sansón. 2015. Long-term herbarium data reveal the decline of a temperate water algae in its range southern limit. Estuarine Coastal and Shelf Science doi:10.1016/j.ecss.2015.05.008

picture

Seagrasses are globally deteriorating, with numerous regressions as a results of data fragmentation. Cymodocea nodosa is the most important seagrass in shallow coastal waters of the Canary Islands. No study has so far investigated temporal population trends at the entire archipelago scale. During te last two decades, a prevalence of negative trends was revealed for three seagrass demographic descriptors (seagrass shoot density, coverage and leaf length), evidencing an overall deterioration in seagrass meadow integrity. These results suggest the need to develop correct management strategies to guarantee the conservation of this seagrass and the meadows it creates.Check it out!. Fabbri, F., F. Espino, R. Herrera, L. Moro, R. Haroun, R. Riera, N. González-Henríquez, O. Bergasa, O. Monterroso, M. Ruiz de la Rosa & F. Tuya. 2015. Trends of the seagrass Cymodocea nodosa (Magnoliophyta) in the Canary Islands: population changes in the last two decades. Scientia Marina, 79(1): 7-13.