Monitoring Abundance and Distribution of Northern Gannets Morus bassanus in Western Iberian Waters in Autumn by Aerial Surveys

Abstract

Several North Atlantic breeding seabirds, such as the Northern Gannet Morus bassanus, use Western Iberian Waters for wintering and migration. In this study, we aimed at producing absolute population estimates of post-breeding Gannets and evaluating the importance of the study area within the species' migration range. We performed six aerial surveys in September and/or October each year between 2010 and 2015, covering 74,840 km 2 in total. Using line transect methodology, 3,672 Gannet sightings were recorded along 10,496.3 nautical miles (nm). Immature individuals and adults comprised approximately 87% of all sightings. Using Distance sampling, overall abundance was estimated at 89,930 birds, ranging from 58,010 individuals in 2014 to 128,140 in 2015. the highest densities per sector areas were recorded in the North and Centre sectors whereas the lowest densities were registered in the Galicia sector, the Spanish region within the study area. Gannets were mostly present in shallow shelf waters of the continental shelf, particularly between 3 and 20 nautical miles offshore. habitat

Using long‐term data series to design adequate protected areas that ensure the conservation of inconspicuous small petrel species

“…In addition, these key areas were not recognised in previous marine spatial plans, and consequently there is a lack of designation of MPAs in these regions (Araújo et al., 2017; Araújo, Correia‐Rodrigues, et al., 2022; Pereira et al., 2018). Furthermore, all Atlantic coast of Iberia is an important migratory flyway for seabird species breeding in northern Europe and moving to lower latitudes during the winter (Araújo, Rodrigues, et al., 2022; Arcos et al., 2009; Paris et al., 2021). The relevance of this coast for numerous seabird species, including the European storm‐petrel, has been highlighted in different forums and international projects (Aranda et al., 2021), suggesting the need to create a ‘migratory corridor’ which connects the already declared SPAs in the area.…”

Exploring the Intricate Connections between the Influence of Fishing on Marine Biodiversity and Their Delivery of Ecological Services Driven by Different Management Frameworks

“…The data of the presence, abundance, distribution, and conservation status of the majority of the non-fishable taxonomic groups (i.e., vertebrate species: sea birds, sea turtles, and cetaceans) throughout the historical series under study were incomplete, which prevented the complete modeling of the ecosystem. Additionally, although we found little information of the presence of cetaceans, birds, and sea turtles in marine areas [34,[45][46][47][48][49][50][51][52][53][54][55][56], we included them in the analysis when possible. It is important to note that all of the biomass data for exploited species utilized in this study solely represent the landings of commercially caught species and should not be considered an accurate reflection of the total biomass extracted from the ocean as it excludes discards, illegal, and recreational fishing due to the lack of official databases.…”

Incorporating drivers of global change throughout the annual cycle in species distribution models for migratory birds: a gap in ecological forecasting

“…Despite the paucity of standardized datasets for anthropogenic factors, over one third of studies (39%) were able to include anthropogenic factors by incorporating proxies of these threats. For example, Araujo et al (2022) used distance to port as a proxy for disturbance from fishing boats and Adams and Root (2022) used building density as a proxy for disturbance from window collisions. Given the rapidly increasing pressure from a growing human population, the omission of anthropogenic processes from SDMs represents a major limitation to our ability to understand and forecast the distribution of species across multiple scales.…”