Assessment of anthropogenic noise pollution on reef Omani ichthyofaunal assemblages

The exposure of marine fauna to anthropogenic noise remains a global environmental issue for marine ecosystems. In fact, this problem is frequently on the rise, owing to the ever-increasing portion of humanity that resides in coastal areas. Over 50% of the global human population is estimated to reside in a narrow band wedged between the continental interior and the ocean; an area constituting less than 10% of all terrestrial lands. This coastal band is increasingly facing the pressures of urbanization that give rise to several adverse effects on the marine habitat, one of which is pollution by anthropogenic noise (hereafter ?noise pollution'). Noise pollution created by anthropogenic activities on shore and at sea (e.g., constructions) and vessel transport can drastically transform the marine soundscape. Given that sound is the sensory stimulus that travels the farthest underwater, noise pollution can be pervasive stressor that often takes a huge toll on marine fauna. Indeed, marine habitats afflicted by noise pollution typically harbor depauperate fauna. At least partly, deterrence effects and mortality of many species may account for these losses, while the species that remain often incur physiological stresses and tend to have maladaptive behaviors that reduce their performance. This scenario is worrisome because it jeopardizes the permanence of healthy and functional marine ecosystems. In the last decade, the Northern coast of Oman has undergone a protracted process of urbanization, which is particularly evident in the Capital Area (Muscat). This area has witnessed the rise of many large-scale coastal infrastructures, including hotels, marinas, ports, and sites of industrial activity. These infrastructures are often coupled with the high use of vessels (motorboats) for transport and recreational purposes. Despite this reality, no assessment of noise pollution at sea has been conducted in the region. Likewise, the potential impacts of noise pollution on fishes, which represent conspicuous components of the marine fauna of Oman, have not yet been measured. The proposed research aims to fill this knowledge gap, precisely by quantifying the acoustic energy (noise pollution) at several reef sites exposed to different and fluctuating acoustic regimes. Differences in acoustic regimes tend to occur spatially and temporally, because of the proximity of high human densities, and differences in habitat use for example, for recreational purposes, which tend to be high in winter but low during the summer seasons, respectively. This research aims to concurrently monitor local ichthyofaunal assemblages via underwater visual censuses (UVC). UVC will be conducted with two complementary approaches, specifically by using baited underwater visual censuses (BRUVs) and using a remotely-operated vehicle (ROV). Together, these complementary approaches will allow characterizing the structure (i.e., richness, abundance, biomass) and functions of species traits (e.g., diets, sizes, propensity for mobility, migratory vs. sedentary life-histories, habitat choice) in each of the local assemblages. At each reef site, benthic conditions (e.g., coral cover, rugosity) and physicochemical data will also be measured, which together will allow running robust statistical models to reveal the precise consequences that noise pollution imposes on ichthyofaunal assemblages. This proposal also seeks to serve as a platform to train postgraduate and undergraduate students in contemporary marine biology, sensory ecology, and conservation research. Last, through workshops, conferences, and scientific articles, the goals and results of this research will be communicated to the widest audience possible, including decision-makers.