No abstract

Offshore platforms, subsea pipelines, wells and related fixed structures supporting the oil and gas (O&G) industry are prevalent in oceans across the globe, with many approaching the end of their operational life and requiring decommissioning. Although structures can possess high ecological diversity and productivity, information on how they interact with broader ecological processes remains unclear. Here, we review the current state of knowledge on the role of O&G infrastructure in maintaining, altering or enhancing ecological connectivity with natural marine habitats. There is a paucity of studies on the subject with only 33 papers specifically targeting connectivity and O&G structures, although other studies provide important related information.Evidence for O&G structures facilitating vertical and horizontal seascape connectivity exists for larvae and mobile adult invertebrates, fish and megafauna; including threatened and commercially important species. The degree to which these structures represent a beneficial or detrimental net impact remains unclear, is complex and ultimately needs more research to determine the extent to which natural connectivity networks are conserved, enhanced or disrupted. We discuss the potential impacts of different decommissioning approaches on seascape connectivity and identify, through expert elicitation, critical knowledge gaps that, if addressed, may further inform decision making for the life cycle of O&G infrastructure, with relevance for other industries (e.g. renewables). The most highly ranked critical knowledge gap was a need to understand how O&G structures modify and influence the movement patterns of mobile species and dispersal stages of sessile marine species. Understanding how different decommissioning options affect species survival and movement was also highly ranked, as was understanding the extent to which O&G structures contribute to extending species distributions by providing rest stops, foraging habitat, and stepping stones. These

In this paper, a live hectocotylus, found inside a stranded female Argonauta argo shell, allowed us to describe the behaviour of this copulatory arm and add new information on its morphology. The hectocotylus penile filament is contained in a special membranous pocket or sac, almost completely transparent, extending from the apex of the basal part to about one-third of the central section. The hectocotylus assumes a folded position to protect the penile filament in the membranous sac. This is probably extracted only when copulation occurs. Our observations seem to suggest that the shell may have the secondary function of storing and protecting the hectocotyli received by males until the copulation. The observations confirmed the high vitality and endurance of the hectocotylus after detachment from the A. argo male.

No abstract

No abstract