Artificial lights at night cause high mortality of seabirds, one of the most endangered groups of birds globally. Fledglings of burrow-nesting seabirds, and to a lesser extent adults, are attracted to and then grounded (i.e., forced to land) by lights when they fly at night. We reviewed the current state of knowledge of seabird attraction to light to identify information gaps and propose measures to address the problem. Although species in families such as Alcidae and Anatidae can be grounded by artificial light, the most affected seabirds are petrels and shearwaters (Procellariiformes). At least 56 species of Procellariiformes, more than one-third of them (24) threatened, are subject to grounding by lights. Seabirds grounded by lights have been found worldwide, mainly on oceanic islands but also at some continental locations. Petrel breeding grounds confined to formerly uninhabited islands are particularly at risk from light pollution due to tourism and urban sprawl. Where it is impractical to ban external lights, rescue programs of grounded birds offer the most immediate and employed mitigation to reduce the rate of light-induced mortality and save thousands of birds every year. These programs also provide useful information for seabird management. However, these data are typically fragmentary, biased, and uncertain and can lead to inaccurate impact estimates and poor understanding of the phenomenon of seabird attraction to lights. We believe the most urgently needed actions to mitigate and understand light-induced mortality of seabirds are estimation of mortality and effects on populations; determination of threshold light levels and safe distances from light sources; documentation of the fate of rescued birds; improvement of rescue campaigns, particularly in terms of increasing recovery rates and level of care; and research on seabird-friendly lights to reduce attraction.
Refined baseline inventories of non-indigenous species (NIS) are set per European Union Member State (MS), in the context of the Marine Strategy Framework Directive (MSFD). The inventories are based on the initial assessment of the MSFD (2012) and the updated data of the European Alien Species Information Network, in collaboration with NIS experts appointed by the MSs. The analysis revealed that a large number of NIS was not reported from the initial assessments. Moreover, several NIS initially listed are currently considered as native in Europe or were proven to be historical misreportings. The refined baseline inventories constitute a milestone for the MSFD Descriptor 2 implementation, providing an improved basis for reporting new NIS introductions, facilitating the MSFD D2 assessment. In addition, the inventories can help MSs in the establishment of monitoring systems of targeted NIS, and foster cooperation on monitoring of NIS across or within shared marine subregions.
Combined analysis of genetic and morphological variation can provide synergistic insights into eco-evolutionary forces shaping biodiversity, as well as tools for conservation and management. Macaronesian limpets are undergoing severe declines due to overexploitation which calls for an evaluation of the evolutionary significance and taxonomic status of populations. This study details the analysis of genetic (mtDNA sequencing) and morphological (geometric analysis of shell shape) variation among Macaronesian populations of Patella aspera, P. rustica, and P. candei. In the case of P. aspera and P. rustica, this also included analysis of mainland conspecifics. mtDNA revealed distinct phylogeographic patterns for the three species. For both P. aspera and P. rustica Macaronesian and continental samples were reciprocally monophyletic, with shallower, and distinct, phylogeographic structure within both clades. For P. candei, the Macaronesian endemic, three reciprocally monophyletic groups corresponding to (i) the Azores, (ii) Madeira and (iii) Selvagens and Canary Islands were resolved. The different patterns for each species are compatible with independent processes of colonization and demographic processes. Morphological differentiation matched the major phylogeographic groupings (i.e., Macaronesian v Continent for P. aspera and P. rustica; Azores/Madeira/Selvagens and Canary Islands for P. candei) compatible with such variation being shaped by genetic drift associated with distinct demographic histories of lineages as well as historical/recurrent selection pressures. The genetic/morphological congruence supports the formal recognition of at least three described P. candei subspecies. Moreover, the data prompt recommendation of the separate management of limpets from each archipelago. At present management efforts are hampered by illegal harvesting of limpets. From an applied viewpoint, this study confirms that morphology retains useful information on genetic status and thus represents a potentially cheap method applicable to limpet conservation.
Despite being an exploited and economically important species, little is known about the reproductive behaviour of Loligo forbesi. During a captive trial performed in a closed seawater system in the Azores, three spawning events were directly witnessed. An account of their main behavioural aspects is given. A number of behavioural components are described for the first time in this species: ‘pair formation’, ‘mate guarding’, ‘egg holding’, ‘egg touching’, ‘white arms’, ‘red accessory nidamental glands’, ‘accentuated testis’, and ‘jockeying and parrying’. The chromatic, locomotor and postural components were very similar to other coastal loliginids observed on spawning grounds. From egg masses recovered on octopus traps, we show that in the Azores spawning activity occurs at least between 25 and 144 m, but greater depths might be expected. We suggest that this squid preferentially deposits egg masses on hard structures probably hiding them in cracks and crevices of volcanic substrata. The existence of spawning aggregations is supported by several factors: (i) these spawning grounds may coincide with the fishing spots, where the exploitation seasonally takes place, given that most individuals caught by fishermen are usually mature (more than 80%); and (ii) mate guarding and jockeying/parrying by males was observed, which is a common feature of spawning aggregation areas, where sperm competition occurs. Furthermore, our results, combined with available published and non-published data further confirm L. forbesi as an intermittent spawner. We estimate that throughout their short life cycle, females of L. forbesi are able to perform up to six spawning events, each composed of an average of ≈2300 eggs.
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