Recreational Divers Research Articles

International classification of diseases and diving illnesses

Post-decompression shock with plasma volume deficit is a very rare event that has been observed under extreme conditions of hypobaric and hyperbaric exposure in aviators and professional divers.We report a case of severe hypovolemic shock due to extravasation of plasma in a recreational scuba diver presenting with inner ear decompression sickness. Impaired endothelial function can lead to capillary leak with hemoconcentration and hypotension in severe cases. This report suggests that decompression-induced circulating bubbles may have triggered the endothelial damage, activating the classic inflammatory pathway of increased vascular permeability.This observation highlights the need for an accurate diagnosis of this potentially life-threatening condition at the initial presentation in the Emergency Department after a diving-related injury. An elevated hematocrit in a diver should raise the suspicion for the potential development of capillary leak syndrome requiring specific treatment using albumin infusion as primary fluid replacement.

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.

Assessing the Effectiveness of Marine Reserves on Unsustainably Harvested Long‐Lived Sessile Invertebrates

Although the rapid recovery of fishes after establishment of a marine reserve is well known, much less is known about the response of long-lived, sessile, benthic organisms to establishment of such reserves. Since antiquity, Mediterranean red coral (Corallium rubrum) has been harvested intensively for use in jewelry, and its distribution is currently smaller than its historical size throughout the Mediterranean Sea. To assess whether establishment of marine reserves is associated with a change in the size and number of red coral colonies that historically were not harvested sustainably, we analyzed temporal changes in mean colony diameter and density from 1992 to 2005 within red coral populations at different study sites in the Medes Islands Marine Reserve (established in 1992) and in adjacent unprotected areas. Moreover, we compared colony size in the Medes Islands Marine Reserve, where recreational diving is allowed and poaching has been observed after reserve establishment, with colony size in three other marine protected areas (Banyuls, Carry-le-Rouet, and Scandola) with the enforced prohibition of fishing and diving. At the end of the study, the size of red coral colonies at all sampling sites in the Medes Islands was significantly smaller than predicted by growth models and smaller than those in marine protected areas without fishing and diving. The annual number of recreational dives and the percent change in the basal diameter of red coral colonies were negatively correlated, which suggests that abrasion by divers may increase the mortality rates of the largest red coral colonies within this reserve . Our study is the first quantitative assessment of a poaching event, which was detected during our monitoring in 2002, inside the marine reserve. Poaching was associated with a loss of approximately 60% of the biomass of red coral colonies.

An examination of recreational divers' underwater behaviour by attitude–behaviour theories

The increasing demand for dive tourism activities has resulted in concerns over scuba divers' incremental impacts on the underwater marine environment. Hence, there is a need to better understand the antecedents of scuba divers' underwater behaviour. This study applied theory of planned behaviour (TPB) and norm activation theory (NAT) of altruistic behaviour in examining the relationship between diving attitude, perceived behavioural control, subjective norms and personal norms (PNs) with responsible underwater behaviour among scuba divers. Using the combination of purposeful and convenience samplings, data were collected from divers (N = 413) who visited the top five most attractive islands in Malaysia. The results supported the use of TPB as a basis for explaining the underwater behaviour of divers. Among the four constructs examined, attitude and PNs were found to be of paramount importance in influencing pro-environmental behaviour. This study also validated the exploratory dimensions that constitute the measurement constructs for scuba diving attitude and responsible underwater behaviour. Scuba diving stakeholders should emphasise continuous education and an integrated programme of marine conservation to enhance divers' attitude and personal commitment towards pro-environmental behaviour. These are crucial for the sustainability of the scuba diving industry.

Assessing the Value of Recreational Divers for Censusing Elasmobranchs

BackgroundAround the world, researchers are using the observations and experiences of citizens to describe patterns in animal populations. This data is often collected via ongoing sampling or by synthesizing past experiences. Since elasmobranchs are relatively rare, obtaining data for broad-scale trend analysis requires high sampling effort. Elasmobranchs are also relatively large and conspicuous and therefore it may be possible to enlist recreational divers to collect data on their occurrence and relative abundance from daily dive activities. For this, however, a good understanding of the value of data collected by recreational divers is essential.Methodology/Principal FindingsHere, we explore the value of recreational divers for censusing elasmobranchs using a diverse set of data sources. First, we use a simulation experiment to explore detection rates of the roving diver technique, used by recreational divers, across a range of fish densities and speeds. Next, using a field survey, we show that inexperienced recreational divers detect and count elasmobranchs as well as experienced recreational divers. Finally, we use semi-structured interviews of recreational dive instructors to demonstrate the value of their recollections in terms of effort and their descriptions of spatial and temporal distributions of sharks in Thailand.Conclusions/SignificanceOverall, this study provides initial ground-work for using recreational divers for monitoring elasmobranch populations. If used appropriately, citizen-collected data may provide additional information that can be used to complement more standardized surveys and to describe population trends across a range of spatial and temporal scales. Due to the non-extractive nature of this data, recreational divers may also provide important insight into the success of conservation initiatives, such as shark sanctuaries and no-take zones.

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.

Patent foramen ovale closure in recreational divers: effect on decompression illness and ischaemic brain lesions during long-term follow-up

ObjectiveTo test the effect of patent foramen ovale (PFO) closure on neurological events in divers.DesignProspective, non-randomised, longitudinal three-arm study.SettingTertiary referral centre.Population104 scuba divers with a history of major decompression illness...

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.

Consumer satisfaction and services: insights from dive tourism

This article focuses on consumer satisfaction in services within the context of tourism, and the dive tourism industry in particular. It identifies the key elements that certified, experienced recreational divers use to determine satisfaction, and discusses the relative importance of the elements. Thereafter, a framework explaining the formation of diver satisfaction is proposed – and the role of emotion is highlighted above other satisfaction antecedents. The findings have practical and academic implications for the wider realms of tourism and other service industries. This research was conducted in Zanzibar, Tanzania, using a combination of participant observation and face-to-face interviews and illustrates the power of such techniques to reach the core of consumer thoughts, actions, and feelings.

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.

Evaluating Methods for Transplanting Endangered Elkhorn Corals in the Virgin Islands

Restoration of rare corals is desirable and restoration projects are fairly common, but scientific evaluation of this approach is limited. We tested several techniques for transplant and restabilization of Acropora palmata (the elkhorn coral), an ecologically important Caribbean coral whose populations have suffered severe declines. In rough weather, fragments break‐off colonies of branching corals like A. palmata as a normal form of asexual reproduction. We transplanted naturally produced coral fragments from remnant populations to nearby restoration sites. Untouched control fragments at the donor site died faster and grew slower than fragments attached to the reef, so attaching fragments to the reef is beneficial. Transplanted fragments grew and died at a rate similar to fragments left at the donor site (both groups were attached to the reef), so there were no effects of moving fragments or differences in habitat quality between donor and restoration sites. Growth and survival were similar using four methods of attaching fragments to the reef: cable ties, two types of epoxy resin, and hydrostatic cement. Corals sometimes compete with the macroalgae that dominate degraded reefs, and clearing surrounding algae improved the growth of fragments. After 4 years, transplanted fragments grew to 1,450 cm2 in area and so were potentially sexually active. Because the methods tested are simple and cheap, they could be used by volunteer recreational divers to restore locally extirpated A. palmata populations or to enhance reefs where natural recovery is slow.

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.

From hunters to nature observers: a record of 53 years of diver attitudes towards sharks and rays and marine protected areas

Human values, perceptions, attitudes and interactions with the natural environment have been found to change over time, with social and economic information used to inform management decisions and actions. Content analysis is applied here to a 53-year long collection of the popular dive magazine, SportDiving, to identify recreational divers’ experiences with regard to sharks and rays, the Great Barrier Reef (GBR) and marine protected areas (MPAs). This analysis suggests there has been a diversification of diver activities with the emergence of passive-observational activities such as SCUBA diving. Attitudes towards sharks and rays have changed significantly, with recreational divers changing from a group that could be described as adventure-seeking hunters to a group that can be described as nature-appreciating observers, suggesting an increase in conservation awareness. The GBR continues to be a highly regarded dive destination, with divers perceiving positive effects of protection within MPAs. However, declines in the abundance of large fish and sharks and rays were occasionally reported throughout the 53 year period. Collectively, these types of data can show changes in resource-use patterns, perceptions and attitudes and provide information that supplements scientific monitoring data. These data may be valuable where scientific data is scarce, historical records difficult to obtain, and where attitudinal change can significantly affect future resource use.

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.

Unite research with what citizens do for fun: “recreational monitoring” of marine biodiversity

Institutes often lack funds and manpower to perform large-scale biodiversity monitoring. Citizens can be involved, contributing to the collection of data, thus decreasing costs. Underwater research requires specialist skills and SCUBA certification, and it can be difficult to involve volunteers. The aim of this study was to involve large numbers of recreational divers in marine biodiversity monitoring for increasing the environmental education of the public and collecting data on the status of marine biodiversity. Here we show that thousands of recreational divers can be enrolled in a short time. Using specially formulated questionnaires, nonspecialist volunteers reported the presence of 61 marine taxa encountered during recreational dives, performed as regular sport dives. Validation trials were carried out to assess the accuracy and consistency of volunteer-recorded data, and these were compared to reference data collected by an experienced researcher. In the majority of trials (76%) volunteers performed with an accuracy and consistency of 50-80%, comparable to the performance of conservation volunteer divers on precise transects in other projects. The recruitment of recreational divers involved the main diving and tour operators in Italy, a popular scientific magazine, and mass media. During the four-year study, 3825 divers completed 18757 questionnaires, corresponding to 13539 diving hours. The volunteer-sightings-based index showed that in the monitored area the biodiversity status did not change significantly within the project time scale, but there was a significant negative correlation with latitude, suggesting improved quality in the southernmost areas. This trend could be related to the presence of stressors in the northern areas and has been supported by investigations performed by the Italian Ministry of the Environment. The greatest limitation with using volunteers to collect data was the uneven spatial distribution of samples. The benefits were the considerable amounts of data collected over short time periods and at low costs. The successful development of citizen-based monitoring programs requires open-mindedness in the academic community; advantages of citizen involvement in research are not only adding large data sets to the ecological knowledge base but also aiding in the environmental education of the public.

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.

Impacts of Recreational Divers on Palauan Coral Reefs and Options for Management

Abstract: Recent growth in the popularity of recreational scuba diving has generated concerns about resulting impacts to coral reefs, particularly in locations such as the Republic of Palau, a world-renowned dive destination with rapidly increasing numbers of visitors. Divers were observed in-water at three of the most visited dive sites in the Rock Islands—Southern Lagoon Area: German Channel, Ngerchong, and Big Drop-off. Dive guides were interviewed about diver impacts at German Channel and Ngerchong. Divers' contact rates with hard coral ranged from 0.87 ± 0.27 to 2.98 ± 0.59 contacts diver-1 10 min-1 (mean ± SEM). Three instances of obvious physical damage were observed. Holding and fin contacts were the most common potentially damaging behaviors of divers, particularly those with cameras or gloves. Guides identified natural impacts (63% of respondents) and divers (34% of respondents) as the primary causes of damage to coral. Proactive management is essential to mitigate any negative impacts of recrea...