Recreational Scuba Divers Research Articles

Survey of SCUBA Divers in Korea Focused on Forensic Implications

This study aimed at surveying recreational scuba divers in order to determine demographic characteristics such as diving certification level and diving times, history of medical illnesses or injuries, and incidence of accidents or risks during underwater diving. For this, the authors contacted the managers of 190 diving clubs, which are listed on an online site called “DiveWeb.”Responses were obtained from 87 diving clubs, amounting to a total of 154 completed questionnaires. The authors also visited a 4-day-long “Seoul International Sports & Leisure Industry Show”and collected 168 completed questionnaires from certified divers who visited the show. The collected data were analyzed by SPSS for Windows, version 17.0. We found the following results among 314 divers: 261 (83.1%) were male, and 221 (70.4%) were aged 30 to 49 years; 174 divers (55.4%) had over 5 years of diving experience; average body mass index (24.13) was within normal limits; number of non-smokers (175) was greater than that of smokers (139); 110 (35.0%) divers reported past or present diseases (allergic rhinitis being the most common) or injury history. Risky situations that were encountered by the divers included currents, underwater environment, buddy system complications, and air depletion during diving. Underwater diving is a potentially hazardous activity, but at present, medical examinations or fitness tests are not a prerequisite for certified divers in Korea. To secure the safety of underwater divers, we need to establish policies for medical checkups and fitness tests before the divers begin training or attain certification.

Serum Levels of S-100B after Recreational Scuba Diving

Recreational scuba diving is a sport of increasing popularity. Previous studies indicating subtle brain injury in asymptomatic divers imply a cumulative effect of minor neural insults in association with diving for professional and/or recreational purposes, over the long-term. This is the first study to investigate putative neural tissue burden during recreational scuba diving by measuring circulating levels of S-100B, a sensitive biomarker of brain injury. 5 male divers performed 3 consecutive dives under conservative recreational diving settings (maximum depth 15 m, duration of dive 56 min, ascend rate 1.15 m/min) with an interval of 12 h between each session. Although a small increase in serum S-100B levels after each dive was apparent, this increase did not quite reach statistical significance (p=0.057). Moreover, no abnormal S-100B values were recorded (mean baseline: 0.06 μg/L, mean post-dive: 0.086 μg/L) and no effect of the 3 consecutive dives on changes in S-100B levels was detected. These results suggest that under the experimental conditions tested, diving does not seem to have a discernible and/or cumulative impact on central nervous system integrity. The extent to which variable diving settings and practices as well as individual susceptibility factors underlie putative neural tissue burden in asymptomatic divers, remains to be established.

Involvement of recreational scuba divers in emblematic species monitoring: The case of Mediterranean red coral ( Corallium rubrum)

Large-scale monitoring programs are fundamental for the management of overexploited or endangered species. When resources are limited, volunteer data collection is an alternative for researchers needing a large amount of data covering a wide geographic extension. Corallium rubrum is endemic to the Mediterranean Sea. Some coastal populations have been deeply studied although there is still lack of knowledge about the distribution or even its presence along Italian coasts. The present work represents cooperation between University of Pisa and SSI-Italy. Recreational scuba divers have been involved in a monitoring project which aims to acquire data on Italian red coral shallow-water populations and increase the awareness of such an emblematic and patrimonial species. During summer 2008 a questionnaire was distributed to recreational divers. The 616 questionnaires analysed, covering more than 1600 km of coasts and 390 h of diving, showed an awareness of recreational divers towards red coral; 80% planned their dive aiming to find red coral and 4% reported colony damage. The same methodology applied in other countries could provide useful and comparable data on this precious marine species.

SCUBA diver observations and placard tags to monitor grey reef sharks, Carcharhinus amblyrhynchos, at Sha'ab Rumi, The Sudan: assessment and future directions

Establishing baseline data on the abundance of threatened shark species is critical for monitoring site- and region-specific population tends over time. This is of particular importance for monitoring sharks at remote locations or in regions where there are no reliable data on shark numbers, fishing effort and current population status. Through establishing a standardized recreational SCUBA diver observation programme, this study examined the number, size and sex-composition of grey reef sharks, Carcharhinus amblyrhynchos, on a remote coral reef system off the Red Sea coast of Sudan. In addition, placard tags were attached to individual sharks to examine coarse scale residency and movement patterns and to determine the effectiveness of this technique. Over a 4.5 month period (December 2007–April 2008), a mean (±SE) of 5.9 ± 0.3 grey reef sharks were observed per diving day with peak numbers of sharks associated with temperatures of 26–26.9°C and strong currents. Estimated mean (±SE) total length of observed sharks was 1.9 ± 0.03 m identifying that most animals were mature. Female sharks were dominant on the site and pregnant females were recorded. Placard tagged sharks (N = 4) were observed by recreational SCUBA divers throughout the study period (23.1%, 20.0%, 16.9% and 3.1% of total observation diving days) indicating sporadic site attachment. The placard tags remained intact and were free of fouling for a total of 175 days. The numbers of grey reef sharks seen on this Red Sea coral complex suggest a healthy, relatively unexploited population. This study demonstrates that the recreational diver community, which forms a large pool of skilled volunteers, can generate baseline data on shark numbers at regularly dived sites and provide insights into the ecology of the observed species. Modification of placard tags, including attachment to the dorsal fin and time corrodible release systems may provide an inexpensive and accepted tool for monitoring individual shark residency and movement patterns. Engaging the recreational SCUBA diver community in a standardized scientific monitoring programme has the potential to monitor trends in shark populations over large spatial and temporal scales.

A new species, Pileolaria aurita (Polychaeta: Spirorbidae), from Japan

A new polychaete, Pileolaria aurita new species, of the family Spirorbidae from the Pacific coast of Honshu, Japan is described. This species clearly differs from all other species of Pileolaria Claparède, 1868 in the morphology of the brood chamber, which bears distally two cone-shaped projections resembling cat ears. Besides, it is the only species of Pileolaria with collar chaetae that lack cross-striation. Worms were found at depths of 20–22 m attached to empty oyster shells directly or to bryozoans covering those shells. The shells were collected from sandy bottoms below artificial reefs constructed for recreational scuba diving.

“Take a deep breath”: how recreational scuba divers negotiate in-water constraints

A significant body of work now exists on what constrains people's leisure. While early theorizations of constraints focused on what prevented individuals from participating in leisure, the literature has expanded to include discussions on how constraints may be negotiated, overcome or substituted. This article explores constraints negotiation in the context of adventurous leisure. This study considers how leisure constraints are negotiated in the in-situ experience of recreational scuba diving. In-depth interviews were conducted with 27 recreational divers. Analysis revealed three interrelated negotiation strategies used to deal with in-situ constraints, namely consolidate, co-operate, or cancel. These negotiation techniques were influenced by factors including divers' histories, perceptions of the severity of the constraint and in-water experience. Findings support the recognition of in-situ constraints negotiation in adventurous leisure. Results highlight the need to reflect on how individuals negotiate constraints during leisure, particularly in difficult environments which can present unpredictable and dangerous risks.

Outdoor recreation and gendered space: the case of men's enthusiasms for hunting, fly-fishing and scuba diving

The purpose of this paper is to explore complexities associated with determining gendered recreational spaces in the context of ‘masculine’ outdoor recreational pursuits, using results from two data sets collected in New South Wales, Australia and North Canterbury, New Zealand, 2006–2008. The first data set is based on face-to-face interviews with 26 male recreational hunters, fly-fishers and scuba divers in Sydney and Christchurch. The second is based on a postal survey of North Canterbury recreational deer hunters and ‘Fish and Game’ licence holders. The results confirm that recreational hunting, fly-fishing and non-touristic scuba diving are distinctly ‘gendered’ activities but the ways in which these are linked to gendered space are complex. The activities may be spatially segregated, occurring in rural and often remote locations, but resourcing these activities mostly takes place in domestic settings, i.e. the home, which commonly involve shared spaces. While a number of methodological cautions regarding the two data sets are acknowledged, this study adds to the limited New Zealand literature on outdoor recreation as gendered space and to wider literature on the importance of acknowledging the social contexts, and hence shared spaces, within which ‘individual’ recreational choices are made.

A video and photographic study of aggregation, swimming and respiratory behaviour changes in the Grey Nurse Shark (Carcharias taurus) in response to the presence of SCUBA divers

The Grey Nurse Shark (Carcharias taurus) is a popular attraction for shark eco-tourism using SCUBA. The species is also ‘globally Vulnerable’ (IUCN 2008. List of Threatened Species. www.iucnredlist.org/). Magic Point (off Maroubra) in Sydney is favoured by recreational SCUBA divers wishing to observe these sharks. The objective of this study was to experimentally test the level of the activities of recreational SCUBA divers on shark behaviour. This study assessed the shark responses to diver group size (4, 8 and 12), time of day (am, noon and pm) and diver distance from the sharks (3 m and 6 m). The study found that diver activity does affect the aggregation, swimming and respiratory behaviour of sharks at this site, albeit at short-term levels. Diver group size had no significant effect on shark aggregation, but the proximity of divers to the sharks was crucial. Shark distribution in the cave changed significantly in the presence of divers at 3 m distance from the cave, but stayed unchanged at 6 m. This was particularly apparent in the presence of large groups of 12 divers at 3 m distance when sharks increased their swim speed and ventilation mechanism from ‘active’ to ‘RAM’ ventilation. Such change coincided with a sudden decrease in ventilation frequency. Our research suggests that these effects are short-term and that sharks resume their behaviour once the divers retreat. If divers abide by the current code of practice for diving at this site, it is unlikely that their activities will substantially impact Grey Nurse Sharks in the long term.

Post-dive ultrasound detection of gas in the liver of rats and scuba divers

In a previous study, we obtained histologic documentation of liver gas embolism in the rat model of rapid decompression. The aim of the study was to assess in the same model occurrence and time course of liver embolism using 2-D ultrasound imaging, and to explore by this means putative liver gas embolism in recreational scuba divers. Following 42 min compression at 7 ATA breathing air and 12 min decompression, eight surviving female rats were anesthetized and the liver imaged by ultrasound at 20 min intervals up to 120 min. A significant enhancement of echo signal was recorded from 60 to 120 min as compared to earlier post-decompression times. Enzymatic markers of liver damage (AST, ALT, and GGT) increased significantly at 24 h upon decompression. Twelve healthy experienced divers were studied basally and at 15-min intervals up to 60 min following a 30-min scuba dive at 30 msw depth. At 30 min upon surfacing echo images showed significant signal enhancement that progressed and reached plateau at 45 and 60 min. Total bilirubin at 24 h increased significantly (p = 0.02) with respect to basal values although within the reference range. In conclusion, 2-D ultrasound liver imaging allowed detection of gas embolism in the rat and defined the time course of gas accumulation. Its application to scuba divers revealed liver gas accumulation in all subjects in the absence of clear-cut evidence of liver damage or of any symptom. The clinical significance of our findings remains to be investigated.

Recreational scuba divers’ knowledge regarding the audiological consequences of the sport

Background: The sport of scuba diving may be associated with possible injuries, especially those concerning the auditory system. Research available focuses on the implications of recreational scuba diving on the auditory system. However, there is a lack of information regarding the knowledge of recreational scuba divers with regard to the audiological consequences of this sport. Method: The aim of this study was to determine whether scuba divers have knowledge pertaining to the consequences of the sport on the auditory system. Thirty-five participants were purposefully selected; their qualifications ranged from an open water diver to a course director. A mixed-method design was implemented in this study with the use of a questionnaire. Results: Forty per cent of the participants were given only the basic medical clearance form to complete; the full medical pack was not made available. However, 97% of the participants signed the medical clearance. One participant did not know that a medical clearance form was required. There were 82% of the participants who had audiological complications subsequent to diving; these individuals did not seek help from an audiologist and continued to dive. Conclusion: There is a need for awareness regarding the effects of diving on the auditory system as participants in this study were not fully aware of the risks of the sport in relation to the ear. The results suggest that participants who experience ear difficulties after dives,do not have sufficient knowledge regarding the ear and the professional who is qualified to assess and manage the difficulties.

Prevalence and characteristics of lung function changes in recreational scuba divers

To investigate the hypothesis that a salt water SCUBA dive may cause bronchoconstriction in some individuals. 100 experienced recreational SCUBA divers acted as their own controls. Spirometry measures were taken with Easyone(TM) spirometers before and after a dive. Measures recorded included FEV1/FVC ratio and forced mid-expiratory flow (FEF25-75%). 60 participants (68% male, 32% female) aged between 19-68 years (mean 47 years) produced data meeting ATS/ERS international standards. Of these, 23% exhibited pre-dive FEV1/FVC ratio values less than 75%. Statistics on paired samples of pre- and post-parameters showed a significant decrease in FVC post-dive but did not show significant reductions in FEV1 or FEV1/FVC. Six (10%) were current smokers and 13 (21%) were former smokers. 25% of participants had reduced FEV1/FVC ratio regardless of undertaking a dive. Consideration of the clinical implications requires further investigation.

CCN: Towards a Model of Comfort, Constraints, and Negotiation in Recreational Scuba Diving

Scuba diving has become a popular form of marine-based tourism and adventure activity. Yet, little empirical information details what transpires during an encounter once a diver descends from the surface. Using a qualitative methodology, the stories of scuba diving experiences were collected and examined in an effort to define some of the prevailing features of an underwater encounter. The presence of comfort, constraint, and negotiation (CNN) emerged as important features of scuba diving. Titled CCN, this article offers a conceptual model that presents the central concepts and depicts the association between comfort, constraints, and negotiation during scuba diving as dynamic elements of the activity.

Orbital Subperiosteal Hematoma From Scuba Diving

Only a few cases of nontraumatic orbital subperiosteal hematoma due to scuba diving have been reported, and this is the first of such cases that underwent surgical intervention. This injury results from negative pressure within the face mask, suctioning orbital tissues into the mask after incomplete equilibration of pressure on descent. Valsalva maneuver is a second mechanism implicated in the etiology of this injury. Recognition of this injury is of the utmost importance because vision loss is a possible complication if there is compression of the optic nerve or increased intraocular pressure. In many cases of nontraumatic orbital hematoma, conservative management is adequate; however, this case was an exception due to worsening exam findings. Divers may be able to prevent this injury by frequent and gentle equilibration of mask pressure on descent.

Can recreational scuba divers alter natural gross sedimentation rate? A case study from a Mediterranean deep cave

Abstract Di Franco, A., Ferruzza, G., Baiata, P., Chemello, R., and Milazzo, M. 2010. Can recreational scuba divers alter natural gross sedimentation rate? A case study from a Mediterranean deep cave. – ICES Journal of Marine Science, 67: 871–874. Submarine caves are environments with features distinguishing them from other littoral habitats but, despite their ecological importance, their response to anthropogenic disturbance has been seldom verified. One potential threat affecting natural communities within caves is represented by recreational scuba diving. Divers' disturbance within marine caves is mainly related to physical contacts and increased sediment resuspension potentially affecting sessile organisms. The aim was to assess the potential effect of recreational divers' frequentation on the natural gross sedimentation rate (GSR) in a Mediterranean deep-water cave. To achieve this, sediment traps were deployed along a scuba trail before, during, and after the peak season for tourist-related diving. No effects of divers' frequentation were evident in terms of alteration of natural GSR, but findings will need to be validated for other caves to asses whether potential disturbance depends on frequentation levels and/or cave characteristics, i.e. sediment grain size or cave depth.

Coral reef quality and recreation fees in marine protected areas

AbstractThe recreational use of marine protected areas (MPAs) is a potential source of funding for MPAs in developing countries, for instance given the willingness of international divers to pay considerably higher diving fees than they currently pay. We conducted a global survey of MPAs containing coral reefs to investigate what factors are important in determining the size of fees charged to recreational SCUBA divers. The survey suggests that a negative perception about diving fees by managers is a more important predictor of fee size than the quality of diving, which can help explain the prevalently low size of diving fees. Decentralized fee systems and higher diving fees can help capture some of the surplus willingness to pay for diving in MPAs, but an excessive reliance on tourism for funding MPA management could expose coral reefs to damages.

Recreational SCUBA diver interactions with the critically endangered Grey Nurse Shark Carcharias taurus

Grey Nurse Sharks Carcharias taurus are listed as ?Critically Endangered? along the east coast of Australia. Magic Point (off Maroubra) in Sydney is favoured by recreational SCUBA divers wishing to observe these sharks. This study was conducted to answer the question: do current recreational SCUBA diving practices at Magic Point have a significant impact on the aggregation behaviour of C. taurus? The study found that diver activity does temporarily affect the behaviour of C. taurus at this site, with a significant difference in the number of sharks and their distribution within the preferred area of occupation inside the cave between diver and non-diver treatments. Small dive groups (= 4 divers) approached the cave closer than large groups, resulting in a greater impact on sharks than large groups positioned further back from the cave. Shark behaviour rapidly returned to pre-diver exposure levels once divers left the area. This study is the first to (a) monitor recreational SCUBA diver activities at a critical habitat site and (b) use a non-invasive behavioural technique to study the behavioural responses of C. taurus towards SCUBA divers in southern NSW. It contributes to improving C. taurus conservation measures along the east coast of Australia by highlighting current diver behaviour and its impact on Grey Nurse Sharks at this site. Results suggest that changes in the current code of practice regarding SCUBA diving at recognized and protected Grey Nurse Shark critical habitat sites should be considered by relevant management agencies.

Ventilation-perfusion inequality in the human lung is not increased following no-decompression-stop hyperbaric exposure

Venous gas bubbles occur in recreational SCUBA divers in the absence of decompression sickness, forming venous gas emboli (VGE) which are trapped within pulmonary circulation and cleared by the lung without overt pathology. We hypothesized that asymptomatic VGE would transiently increase ventilation-perfusion mismatch due to their occlusive effects within the pulmonary circulation. Two sets of healthy volunteers (n = 11, n = 12) were recruited to test this hypothesis with a single recreational ocean dive or a baro-equivalent dry hyperbaric dive. Pulmonary studies (intrabreath V A/Q (iV/Q), alveolar dead space, and FVC) were conducted at baseline and repeat 1- and 24-h after the exposure. Contrary to our hypothesis V A/Q mismatch was decreased 1-h post-SCUBA dive (iV/Q slope 0.023 ± 0.008 ml−1 at baseline vs. 0.010 ± 0.005 NS), and was significantly reduced 24-h post-SCUBA dive (0.000 ± 0.005, p < 0.05), with improved V A/Q homogeneity inversely correlated to dive severity. No changes in V A/Q mismatch were observed after the chamber dive. Alveolar dead space decreased 24-h post-SCUBA dive (78 ± 10 ml at baseline vs. 56 ± 5, p < 0.05), but not 1-h post dive. FVC rose 1-h post-SCUBA dive (5.01 ± 0.18 l vs. 5.21 ± 0.26, p < 0.05), remained elevated 24-h post SCUBA dive (5.06 ± 0.2, p < 0.05), but was decreased 1-hr after the chamber dive (4.96 ± 0.31 L to 4.87 ± 0.32, p < 0.05). The degree of V A/Q mismatch in the lung was decreased following recreational ocean dives, and was unchanged following an equivalent air chamber dive, arguing against an impact of VGE on the pulmonary circulation.

Assessing the distribution and relative abundance of wobbegong sharks (Orectolobidae) in New South Wales, Australia, using recreational scuba-divers

Wobbegongs are benthic sharks that are commercially targeted in New South Wales (NSW), Australia. Given a dramatic reduction of more than 50% in landed catch in a decade, there is a clear need to ensure that basic ecological data such as distribution and abundance are available for management use. Opportunistic sightings of wobbe- gongs collected by recreational scuba-divers were used to assess the distribution and relative abundance of wobbegongs in NSW. From July 2003 until January 2005, 304 dives were undertaken by recreational divers and 454 wobbegongs were reported. Larger numbers of wobbegongs were sighted in northern compared to southern NSW. Spotted and ornate wobbegongs were sighted in similar numbers, but species composition was highly variable across locations. Only a few juvenile and newborn spotted wobbegongs were sighted, whereas small ornate wobbegongs were mostly sighted north of central NSW. The latter were possibly the third, cryptic species, the dwarf ornate wobbegong. The paucity of sight- ings of small wobbegongs suggests that juveniles and newborns are inconspicuous to divers or that small wobbegongs are found in areas not visited by divers. Potential species and size segregation suggest that closing areas to fishing may enable populations to sustain current levels of commercial exploitation. The cost-effectiveness of using recre- ational scuba-divers to opportunistically collect distribution and relative abundance data was apparent from this study. However, the lack of spatial and temporal homogeneity in diving effort suggests that future studies should consider incorporating organized surveys and a facilitator, rather than using opportunistic records of sightings.

Finding comfort in adventure: experiences of recreational SCUBA divers

Adventure experiences are most often examined from a position that seeks to understand interpretations of risk and uncertainty. This paper has adopted an alternate view in seeking to consider aspects of participants’ comfort during an adventure‐based experience, namely recreational SCUBA diving. Interviews were held with divers who had variation in their level of experience and involvement with the activity. An interpretive approach to analysing the interview data revealed physical, social, psychological and visual contexts of comfort within SCUBA diving. Themes that reflect comfortable experiences are important to recreational SCUBA diving and the broader context of leisure.

Low-back problems in recreational self-contained underwater breathing apparatus divers: Prevalence and specific risk factors

Low-back problems (LBP) are one of the most common musculoskeletal disorders in the general population, with reported lifetime prevalences of 50% to 80%. Also, certain sports participants (e.g. gymnasts, alpine skiers, runners) are at risk of LBP and its repercussions. This epidemiological study was undertaken to examine the lifetime and 1-year prevalence of LBP among recreational Flemish self-contained breathing apparatus (scuba) divers and to identify general and sport-specific risk factors associated with the occurrence of LBP. A retrospective self-assessment questionnaire was developed and assessed for validity and reliability, to gather data concerning demographics, LBP prevalence and associated risk factors and injuries among active scuba divers. A total of 181 recreational scuba divers (men: n = 138, mean age 40.3 ± 12.8 years; women: n = 43, mean age 35.0 ± 10.9 years) from 10 randomly selected internationally recognised scuba diving clubs participated in the study. Lifetime and 1-year prevalence of LBP among recreational Flemish scuba divers were 55.8% and 50.3%, respectively. General risk factors for LBP were found to include prior history of LBP, structural abnormalities, heavy workload, pregnancy and parturition, general fatigue and bending forwards and backwards. Scuba divers suffering from LBP generally had a significantly higher dive certificate than those without LBP (p = 0.007). Symptomatic scuba divers also used significantly more weights on their weight belts during indoor training (p = 0.003) and during outdoor dives with a dry suit (p = 0.044) as compared to asymptomatic scuba divers. In scuba diving, reliable sport-specific risk factors for LBP were found to be scarce. Further biomechanical research is required to point out whether or not scuba diving characteristics actually contribute to LBP.