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- Trade of live bait in Portugal and risks of introduction of non-indigenous species associated to importationPublication . Sá, Erica; Fidalgo E Costa, Pedro; Cancela Da Fonseca, Luís; Alves, Ana; Castro, Nuno; Cabral, Sara; Chainho, Paula; Canning Clode, João; Melo, Pedro; Pombo, Ana; Costa, José LinoDifferent invertebrate groups are often exploited on sediment shores and mudflats, including polychaetes, sipunculids, bivalves and crustaceans. The commercial importance of polychaetes and sipunculids, that has increased in the early 2000's because of its use as a food source for the aquaculture sector and a growing demand of worms for use as sea angling bait, seems to be declining nowadays. In Portugal bait harvesting from natural populations became insufficient to meet market demands and as a result, polychaetes and sipunculids have been imported in recent years. Due to this it was important to know the ways of the live bait import to Portugal, and to assess the risk of introduction of non-indigenous species associated to that live bait trade. The origin and quantities of imported live bait were determined by examining the landing's records at Lisbon airport, from two periods: 2002-2003 and 2012-2015. Live worms imported to Portugal arrived almost exclusively from China, USA and Vietnam. Monthly import data and bait registers at fish auction landings were significantly correlated, showing that bait captures and imports are directly related to higher bait demand. In addition, the risk of live bait's importation as an introduction vector for non-indigenous species was evaluated by examining the bait boxes content. Five worm species were identified in bait boxes with foreign species: Glycera dibranchiata, Namalycastis rhodochorde, Perinereis cultrifera, Perinereis linea, and Sipunculus (Sipunculus) nudus. The examination of bait boxes in Portugal suggested that there is a low risk of associated hitchhiker species introduction and dissemination, mostly because of packaging procedures, which should be advised. The same is not true to the non-indigenous live bait species.
- Marine invasions in a warming Macaronesia : understanding diversity and connectivity patterns through field, laboratory and analytical studiesPublication . Castro, Nuno; Canning-Clode, João; Costa, José Lino; Gestoso, IgnacioThe introduction of Non-Indigenous Species (NIS) is a global phenomenon with devastating consequences for biodiversity, ecosystem services, and human well-being. This thesis aims to unravel the complexities of NIS dynamics, offering insights into their effects and increasing the comprehensive understanding of these crucial ecological phenomena within the context of climate change in the marine environment of Macaronesia. The thesis is divided into four chapters, each addressing specific facets of the NIS issue. The first section briefly introduces invasion ecology in a marine Macaronesian context. The first Chapter provides a comprehensive inventory of NNS (Non-Native Species) in Macaronesia, highlighting the influence of various factors, including maritime traffic, on NNS presence. This pioneering study reveals the region's baseline number of NNS, with variations among different archipelagos. It features the critical role of marine traffic and infrastructure in hosting NNS. Chapter Two explores the role of maritime traffic as a primary vector for NIS introduction in Madeira. It identifies invasion corridors by analyzing significant traffic routes and underscores the importance of understanding these corridors for NIS management. Chapter three delves into propagule pressure and barriers for NIS establishment and proliferation. This Chapter is divided into three segments. First, it investigates how maritime traffic intensity and artificial structures influence fouling assemblages and demonstrates the impact of recreational boating in NIS dispersion. In the second part of this Chapter, a detailed study of NIS in Macaronesia is conducted to detect variations in NIS numbers, abundance, and recruitment. Abiotic factors like temperature and latitude and biotic elements such as species richness and competition are analysed. The findings partially confirmed a latitudinal trend, with lower latitudes showing lower NIS recruitment and NIS percentage cover. The final segment of Chapter Four examines the impacts of Marine Heat Waves (MHWs), exacerbated by global warming, on Native and NIS in a marine environment. The study showed that longer and more intense MHWs events had an overall negative impact, affected the invasibility of sessile assemblages and encouraged more adapted species to thrive. Chapter Five focuses on the NIS management aspect, assessing the invasion risk of a tropical fish species that arrived in Madeira due to climate change. Finally, the general discussion evidences the absence of NIS biosecurity or management protocols in Macaronesia, emphasizing the need for preventive measures to tackle NIS. In conclusion, this research constitutes a vital milestone in comprehending the ecology of marine biological invasions in Macaronesia and advancing efforts to prevent, manage, and respond to the evergrowing threat of NIS in a rapidly changing world.