Search Results (94)

The environmental problem of abandoned fishing gear (e.g., ghost nets) exists on a world scale. It impacts marine biodiversity for decades after the nets has become lost in the ocean. In Cyprus (eastern Mediterranean), ghost nets are found almost everywhere around the island, threatening marine life and human activities, such as scuba diving, fishing and navigation. To achieve meaningful outcomes for biodiversity conservation and the management of an offshore site that is particularly affected by ghost nets, the Jubilee Shoals, this issue is addressed in this study with an evidence-based approach. Pre-removal surveys were necessary to assess the nets and produce the environmental, ecological and structural data for the calculation of the Gear Removal Index (GRI). The results of a revised version of the index (GRI+) that includes species of conservation interest and invasive species were cross-checked in the field by divers with experience in marine ecology and similar removals. About 3 km of nets in total were successfully removed. The implementation of the GRI+ was an important proof-of-concept for environmental managers, aiding them to decide whether it would be necessary (or not) to perform removals and highlighting the index as a useful tool for the protection and management of Cyprus’ marine habitats. Full article

Australian scuba fatalities over 50 years were examined to determine temporal changes over two consecutive periods, 1972–1999 and 2000–2021. The Australasian Diving Safety Foundation database and National Coronial Information System were searched to identify scuba deaths from 1972 to 2021. Historical data, police and witness reports, and autopsies were recorded and comparisons made between the two periods. Of 430 total deaths, 236 occurred during 1972–1999 and 194 during 2000–2021, with average annual fatalities of 8.4 and 8.8, respectively. The proportion of males reduced (83% to 76%) and median ages rose (33 to 47 years) with a large rise in the percentage of casualties among people aged 45 years or older (24% to 57%). There were increases in certified divers (64% to 81%) and in the proportion of divers who were with a buddy at the time of their incident (17% to 27%), as well as a decrease in out-of-gas incidents (30% to 25%). A reduction in primary drowning (47% to 36%) was accompanied by more than a doubling of cardiac-related disabling conditions (12% to 26%). The substantial increase in casualties’ ages and of the proportions of casualties aged 45 or more and of females between the periods indicate the inclusion of a broader cohort of participants and ageing of longtime divers. The reduction in primary drowning was likely due to increased training and improvements in equipment, particularly BCDs and pressure gauges. The rise in cardiac-related deaths was due to an older and more obese cohort. Improved health education and surveillance and improved dive planning are essential to reduce such deaths. Full article

The demand for maritime–coastal tourism has been intensifying, but its offerings are sometimes limited to a few activities. Some of these activities do not require specific skills or certifications, while others do. This study aimed to investigate what type of activities are carried out by tourism and recreational vessels in the coastal area of the central Algarve (Portugal). To this end, data from the automatic identification system (AIS) of recreational vessels was used to monitor and categorise these activities in a non-intrusive manner. A model (TORMA) was defined to facilitate the analysis of AIS data and relate them to five independent variables (distance from the coast, boat speed, bathymetry, seabed type, and number of pings). The results of the analysis of more than 11 thousand hourly AIS records for passenger, sailing, and charter vessels showed that the 14 most regular ones had strong seasonal patterns, greater intensity in summer, and spatial patterns with more records near some coastal cliffs. This study provides valuable information on the management of motorised nautical activities near the coast and at sea, contributing to more informed and effective tourism regulation and planning. Full article

Background/Objectives: The inspiratory muscles play a fundamental role in cardiorespiratory performance, especially in water sports. The main objective of this study was to investigate the effects of an inspiratory muscle warm-up (IMW) protocol on the performance and respiratory parameters of scuba divers prior to performing two diving tests, one static and the other dynamic. Methods: Eight young, active divers (six men and two women; 26.63 ± 4.67 years of age) volunteered for the study. In two sessions, one using an IMW protocol and the other without IMW, participants performed two underwater tests with a gas tank: a static immersion at the bottom of the pool for 5 min and a dynamic test consisting of swimming underwater for 12 min at 1 m/s. Some cardiorespiratory parameters such as gas expenditure, oxygen saturation (SO₂), heart rate (HR), spirometry, and rating of perceived exertion (RPE) were measured before and after each of the tests. Results: Significant differences were observed in gas expenditure using IMW in both static and dynamic testing (p < 0.05) and in RPE in dynamic testing (p < 0.05). HR values were significantly higher in the pre-dynamic test with IMW and the post-static test with IMW. Finally, with the use of IMW, spirometry values were significantly higher (p < 0.05) in static tests after immersion, whereas in the dynamic test, they were significantly higher before the immersion (p < 0.05). Conclusions: Based on the results of this study, the use of the IMW prior to a dive would be recommended for better overall physical performance, oxygen expenditure, improved pulmonary function, and lower perceived exertion. Full article

The infraclass Euthyneura (Mollusca, Heterobranchia) exhibits significant diversity in morphology, size, life habits, and color. Several species are important for research in evolution, ecology, chemistry, and pharmacology. Despite Colombia’s expansive Pacific and Caribbean coasts, which host ecosystems such as rocky shores and coral reefs, key habitats for sea slugs and sea hares, the biodiversity of Euthyneura remains largely understudied. This study aims to expand the inventory of Euthyneura diversity in intertidal and shallow subtidal rocky and coral reef environments in Colombia’s Pacific (Uramba Bahía Málaga National Natural Park) and Caribbean (Seaflower Biosphere Reserve) areas. Rapid biodiversity assessments using snorkeling and errant scuba diving at depths of 1–40 m resulted in the documentation of 31 species (14 in Caribbean coral reefs and 17 in Pacific intertidal and shallow subtidal rocky shores and reefs). Eleven species were new records. The family Aplysiidae was the richest with five species, followed by Facelinidae with four, and Aeolidiidae, Discodorididae, Chromodorididae, and Plakobranchidae with three each. Given the limited sampling effort (~40 h in the Caribbean and ~20 h in the Pacific) and the substantial new data collected, it is evident that there is still much to learn about this group in these areas. Increased efforts, combined with detailed morphological and molecular techniques, will enhance our understanding and documentation of Euthyneura diversity in Colombia. Full article

Marine life exploration is constrained by factors such as limited scuba diving time, depth restrictions for divers, costly expeditions, safety risks to divers’ health, and minimizing harm to marine ecosystems, where traditional diving often risks disturbing marine life. This paper introduces Nu (named after an ancient Egyptian deity), a 3D-printed Remotely Operated Underwater Vehicle (ROUV) designed in an attempt to address these challenges. Nu employs Long Range (LoRa), a low-power and long-range communication technology, enabling wireless operation via a manual controller. The vehicle features an onboard live-feed camera with a separate communication system that transmits video to an external real-time machine learning (ML) pipeline for fish species classification, reducing human error by taxonomists. It uses Brushless Direct Current (BLDC) motors for long-distance movement and water pump motors for precise navigation, minimizing disturbance, and reducing damage to surrounding species. Nu’s functionality was evaluated in a controlled 2.5-m-deep body of water, focusing on connectivity, maneuverability, and fish identification accuracy. The fish detection algorithm achieved an average precision of 60% in identifying fish presence, while the classification model achieved 97% precision in assigning species labels, with unknown species flagged correctly. The testing of Nu in a controlled environment has met the system design expectations. Full article

Initiatives such as the United Nations Decade of Ocean Science for Sustainable Development and Seabed 2030 promote seabed mapping worldwide. In Brazil, especially on the Espírito Santo Continental Shelf, high-resolution seabed mapping has revealed an unknown complex seascape. Circular depressions (CDs) were mapped for the first time in the Costa das Algas Marine Protection Area. Herein, we aim to present the CD metrics characteristics and discuss their relationship with morphology and relevance as a habitat based on multibeam bathymetry and ground truthing. A total of 3660 depressions were mapped between 46 and 85 m in depth, reaching an area of 460 m² and 5 m relief. The continental shelf morphology was subdivided into three sectors based on morphology: inter-valleys, valley edges, and valley flanks, and eleven sites were selected for direct sampling/imaging at the CDs along the sectors. The direct sampling was carried out by scuba-diving with video images and sediment samples collected inside and outside the depressions. The deeper central parts of the circular depressions appear to function as a sink, presenting aggregations of rhodoliths or other carbonate fragments. In most inter-valley depressions, mounds were observed along the edges of the depression. We did not have any indication of gas seeps and no clear sedimentological or morphological control on their occurrence. We first hypothesize that their origin results from combined diachronous processes. The circular depressions mapped at high resolution could be related to sea level processes acting during the last glacial period and shelf exposure, i.e., relict features. The CDs are responsible for biomass aggregation and fish bioturbation, forming holes and rubble mounds, representing a modern process occurring on a centimetric scale. The data collected so far indicate that this fine-scale feature is an important habitat for different fish species. The modern maintenance of these structures could be due to low sedimentation regime areas shaped by biotic excavation. Full article

The malacological faunae of two algal habitats with different lighting conditions—a sciophilous wall and a photophilous one—both located in Tossa de Mar (Costa Brava, Girona, NE Spain), have been studied to examine the differences in the malacological communities, their distribution over time, and the role played by micromollusks in these algal habitats. Every two months, for a year, samples were collected via scuba diving and scraping standardized surfaces (20 × 20 cm) of the algal communities. In the laboratory, the samples were washed and filtered using two metal sieves (2 mm for coarse fraction and 513 µm for fine fraction). Mollusks were separated, identified, and later analyzed statistically to assess biodiversity indices and sample grouping. A total of 7913 mollusk specimens from 148 species (112 Gastropoda; 32 Bivalvia and 4 Polyplacophora) were identified across all samples, with 1669 specimens (84 species) from the sciophilous algae and 6244 specimens (133 species) from the photophilous algae. Moreover, 10 species accounted for 76.27% of the total abundance, with each species represented by over 100 specimens in the total samples. The gastropod Bittium latreillii was the most abundant species, with 2106 specimens recorded. Regarding the two fractions, 337 specimens (69 species) were found in the coarse fraction, while 7576 specimens (111 species) were found in the fine fraction. Significant differences were obtained between samples with respect to time, habitat type, and size fraction. The Shannon–Wiener biodiversity index values indicated differences between the two communities over time, as well as variations in biodiversity, with the photophilous community exhibiting higher values. It was demonstrated that algal thalli provide a highly suitable substrate for juvenile forms and micromollusks. Our findings, combined with the literature and various online citations, establish Tossa de Mar as the town on the Catalan coast with the best-documented malacological fauna. Full article

Dokdo is an island located in the easternmost part of Korea, which has high levels of biodiversity of birds and fish, especially marine invertebrates. However, the biodiversity of microalgae, especially diatoms (Bacillariophyta), is relatively unknown, despite their ecological importance as primary producers of the marine food web and bioindicators of environmental conditions associated with climate change. To understand the biodiversity of seaweed-associated diatoms from Dokdo, we collected macroalgae present at a depth 5–15 m by SCUBA diving on 17 October 2017. There were a large number of diatoms (over 130 species), even though it was a one-time survey. As it includes too many taxa to cover at once, voucher flora for other taxonomic groups will be provided through the continuous serial papers. This is the first series of seaweed-associated diatoms, with 26 species belonging to the subphyla Melosirophytina and Coscinodisophytina, and the class Mediophyceae. Among these, seven species including one new taxon were reported for the first time in Korea, which, along with the geopolitical characteristics of the survey area, proved that there is no domestic interest in seaweed-related diatoms. In particular, the appearance of species that have been reported in subtropical waters, such as the order Ardissoneales, requires continuous monitoring of marine seaweed-associated diatoms to confirm whether their colonization in Dokdo waters was due to climate change or species-specific water temperature tolerance. Full article

SCUBA diving poses risks due to pressure changes during descent (compression) and ascent (decompression). Decompression sickness (DCS) occurs due to gas bubble formation as the pressure decreases, causing joint pain, numbness, dizziness, or even paralysis and death. Immediate treatment involves 100% oxygen to help eliminate inert gases and hyperbaric oxygen therapy (HBOT), which is essential to reduce gas emboli formation and inflammation, thus improving symptoms. We evaluated oxy-inflammation biomarkers in the saliva and urine of nine subjects pre- and post-technical dive on the Haven wreck (GE, Italy). A case of DCS occurred during the dive. The injured diver was treated immediately with O₂ and transported to the hyperbaric center of “ASST Ospedale Ca Granda” in Milan. He was treated following the U.S. Navy Treatment Table 5 at 2.8 ATA and the day after with Table 15 at 2.4 ATA. Venous blood and urine samples were collected before and after each HBO treatment. Our study shows that dive increased oxy-inflammation biomarkers (ROS +126%; lipid peroxidation +23%; interleukins-6 +81%, -1β +19%, and TNFα +84%) and nitric oxide metabolites levels (+36%). HBOT after a DCS episode reduced oxidative stress, lowering the very high marker of lipid peroxidation (8-iso-PGF2α), and inhibited inflammatory interleukins. Overall, HBOT improved physiological responses in the diver affected by DCS. Full article

Marine sports tourism has emerged as a significant niche within the broader tourism industry, offering unique opportunities for economic development, social well-being, and environmental sustainability. This study presents a comprehensive bibliometric analysis of marine sports tourism research, examining publications up to July 2024 from the core collection databases of the Web of Science. The analysis assesses the productivity, research themes, and emerging trends within this field. The results indicate significant growth in research output over the past three decades. Saayman M., Giglio V. J., and Van der Merwe P. are identified as the most productive authors, while Australia, the United States, China, and the United Kingdom demonstrate high levels of research productivity and impact. Ocean & Coastal Management is recognized as the most impactful journal. Keyword co-occurrence and clustering analysis revealed four major research clusters: Environmental Impacts and Community Interaction, Conservation and Ecological Impacts, Behavioral Studies and Perceptions, and Management and Scuba Diving. Topic trend analysis highlights a shift in research focus from the environmental impacts of marine sports tourism to a more integrated approach that considers environmental, economic, and social dimensions. Based on the current research landscape and developmental trajectory, the study proposes future research directions, including addressing identified research gaps, enhancing the resilience of marine sports tourism activities, and developing holistic approaches to sustainable tourism from an interdisciplinary perspective. Full article

This review examines the relationship between the physiological demands of diving and premature ventricular complexes (PVCs) in divers. In the general population, some individuals have a greater tendency to experience PVCs, often without awareness or a clear understanding of the triggering factors. With the increasing availability and popularity of both scuba and apnoea diving, more people, including those with a predisposition to PVCs, are engaging in these activities. The underwater environment, with its unique stressors, may increase the risk of arrhythmogenic events, particularly PVCs. Here, we review the prevalence, pathophysiology, and aggravating factors of PVCs in divers, emphasising the need for a comprehensive cardiovascular assessment. Evidence suggests a higher prevalence of PVCs in divers compared with the general population, influenced by factors such as age, dive depth, gas bubbles, cold water immersion, pre-existing cardiovascular diseases, and lifestyle factors. The change in environment during diving could potentially trigger an increased frequency of PVCs, especially in individuals with a pre-existing tendency. We discuss diagnostic strategies, management approaches, and preventive measures for divers with PVCs, noting that although guidelines for athletes can be adapted, individual assessment is crucial. Significant knowledge gaps are identified, highlighting the need for future research to develop evidence-based guidelines and understand the long-term significance of PVCs in divers. This work aims to evaluate potential contributing factors to PVCs in divers and identify individuals who may be at higher risk of experiencing major adverse cardiovascular events (MACEs). This work aims to improve diver safety by promoting collaboration between cardiologists and diving medicine specialists and by identifying key areas for future investigation in this field. This work aims to improve the safety and well-being of divers by understanding the cardiovascular challenges they face, including pressure changes, cold water immersion, and hypoxia. We seek to elucidate the relationship between these challenges and the occurrence of PVCs. By synthesising current evidence, identifying knowledge gaps, and proposing preliminary recommendations, we aim to encourage collaboration between cardiologists and diving medicine specialists to optimise the screening, management, and risk stratification of PVCs in the diving population. Full article

Prvić Island (Kvarner area in the NE channel part of the Adriatic Sea) is a part of the Natura 2000 protected area network. A recent tombolo is located on the SW coast of Prvić Island, and much larger submerged tombolos are located on the shoal towards the south. Both phenomena are unique to the Croatian coast of the Adriatic Sea. The inland part of the tombolo was surveyed using an Unmanned Aerial Vehicle, and a 3D point cloud was created using Structure from Motion with Multi-View Stereo photogrammetry. The body of the talus breccia behind the tombolo has a triangular form. Large collapsed rocky blocks form the cape vertex. This cape is in a state of equilibrium in the present oceanographic conditions but might be eroded due to predicted rises in sea level. The submarine zone was explored using scuba-diving equipment and Remotely Operated Vehicles. A large triangle-shaped shoal consists of flysch. Parallel vertical sandstone layers that look like artificially built walls are more than a hundred metres long. The carbonate breccia is located at the end of the shallow zone. The conditions for the final formation of the submerged shoal were created during the sea level stagnation in the Holocene. Full article

This research delves into the molecular and morphological characteristics of myzostomid worms associated with common shallow-water feather stars (Echinodermata: Crinoidea: Comatulidae) in the coastal waters near Sanya, Hainan Island. Through the examination of specimens collected at depths of up to 10 m using scuba diving techniques, we describe three new species (Myzostoma ordinatum sp. nov., M. scopus sp. nov., and M. solare sp. nov.) and report the first record of Myzostoma polycyclus Atkins, 1927 in the South China Sea. The absence of overlap with the seven previously documented Myzostomida species in the shallow waters of Hong Kong and Shenzhen reveals significant gaps in our understanding of marine biodiversity in the South China Sea. These findings, combined with an analysis of available molecular data, underscore the potential existence of unexplored and diverse symbiotic relationships among marine invertebrates within the region. Full article