Diver Behaviour Research Articles

SCUBA diver behavior, diver carrying capacity and its implications for sustainable reef management

Coral reefs are vulnerable to natural and anthropogenic impacts, especially tourism activities such as SCUBA diving and snorkeling. This study aims to assess diver carrying capacity and the impacts caused by SCUBA divers related to certification level and lionfish spear, through an underwater monitoring of 180 divers in Roatan, Honduras. Results reveal substantial variation in carrying capacity among dive sites, with a notable disparity of over 13,000 divers/year between sites with the lowest and highest capacities. Divers’ behavior has significant implications for reef physical integrity. This study highlights the need to reassess the effectiveness of lionfish spearfishing as a control for invasive species and emphasizes the importance of comprehensive workshops and courses to enhance divers' awareness of potential ecological impacts. These findings contribute to understanding the ecological implications of recreational diving, calling for sustainable management practices and targeted educational efforts. Furthermore, the study underscores the significance of estimating and managing carrying capacity for long-term marine ecosystem sustainability. Incorporating SCUBA diving carrying capacity as a crucial tool for adaptative management enables monitoring and regulation of diver numbers in relation to reef status and tourism pressure.

Feeding ecology of wintering Great Northern Divers Gavia immer in Argyll, Scotland

I investigated the role of tide and time of day on feeding success and prey species of the Great Northern Diver Gavia immer at its wintering grounds in Argyll, Scotland. Focal animal sampling was used on solitary divers to determine their activity during different tidal states and at different times across four main sites. When a bird performed ten successive dives, feeding success was recorded and inferred. Divers spent more time feeding early in the morning in comparison to other periods of the day. Less time was spent feeding at high tide, but this difference was not statistically significant. Divers spent 55% of the daylight period feeding, with most of this feeding time spent underwater. Prey was brought to the surface during 15% of dives and birds drank (thought to indicate ingestion of prey underwater) following 33% of dives. Crabs and flatfish were the main observed prey items, with 61% of the prey brought to the surface estimated to have a mass of less than 5 g, although items up to 80 g were consumed on occasion. The composition of prey brought to the surface varied between sites, with more crab prey items seen on sites with rocky substrates. I investigated differences in the feeding behaviour of adult and first-winter Divers at one site, but observed few differences. The importance of high-quality feeding sites for Great Northern Divers, and the implications of time spent underwater within current census techniques are discussed.

Scuba divers' behavior and satisfaction in a new marine protected area: Lessons from the implementation of a best practices program

Subtropical reefs have suffered from increasing threats and impacts mainly from anthropogenic activities. These reefs also have socioeconomic relevance being in many locations an important income source through recreational activities. This study aimed to assess the potentially damaging behaviors of scuba divers on benthic reefs organisms in the first year of a new Brazilian diving destination, the Alcatrazes Archipelago Wildlife Refuge. We also assessed diver satisfaction to verify the effects of management measures on diver experience. Management measures were implemented through a best practices program aiming to improve low-impact diver behavior. Scuba divers caused the lowest contact rate with the reef described in the literature, maintaining low rates of potentially damaging behaviors over the year. Overall, each diver made an average of 0.63 contacts with the reef and 0.06 with the reef biota per 45 min of dive. Most of the contacts were unintentional and occurred in the first 10 min of the dive. The overall satisfaction of divers was high in all seasons. However, regarding specific attributes, experienced divers were more sensitive to increased underwater supervision. Our results highlight the effectiveness of continued initiatives like best practices program to improve low-impact diver behavior. Visitation monitoring programs are essential to understand the behavior of scuba divers and how the restrictions may affect diver enjoyment in reef environments.

Modeling and thermal management of proton exchange membrane fuel cell for fuel cell/battery hybrid automotive vehicle

The proton exchange membrane fuel cell (PEMFC) stack is a key component in the fuel cell/battery hybrid vehicle. Thermal management and optimized control of the PEMFC under real driving cycle remains a challenging issue. This paper presents a new hybrid vehicle model, including simulations of diver behavior, vehicle dynamic, vehicle control unit, energy control unit, PEMFC stack, cooling system, battery, DC/DC converter, and motor. The stack model had been validated against experimental results. The aim is to model and analyze the characteristics of the 30 kW PEMFC stack regulated by its cooling system under actual driving conditions. Under actual driving cycles (0–65 kW/h), 33%–50% of the total energy becomes stack heat; the heat dissipation requirements of the PEMFC stack are high and increase at high speed and acceleration. A PID control is proposed; the cooling water flow rate is adjusted; the control succeeded in stabilizing the stack temperature at 350 K at actual driving conditions. Constant and relative lower inlet cooling water temperature (340 K) improves the regulation ability of the PID control. The hybrid vehicle model can provide a theoretical basis for the thermal management of the PEMFC stack in complex vehicle driving conditions.

Quantifying the Effects of Diver Interactions on Manta Ray Behavior at Their Aggregation Sites

Manta rays (Mobula birostris, Mobula. cf. birostris, andMobula alfredi), the largest mobulid rays, are subjected to exploitation and overfishing in certain parts of the world. Tourism has been supported as a sustainable alternative for the conservation of the species, and a potential source of economic spillover to local populations. Nevertheless, the effects of tourism over these highly social animals remains unknown. Manta rays aggregate at three sites in Mexico: Oceanic manta rays (M. birostris)in The Revillagigedo Archipelago and Banderas Bay in the Pacific. Caribbean manta rays (M. cf. birostris) around Isla Contoy National Park in the Caribbean. We analyzed the behavior of manta rays using video data collected by local researchers and tourism operators to determine how diver behaviors and techniques (SCUBA and free diving) affect them. Diver activities were grouped into passive and active categories. We described 16 behaviors and grouped them into four behavioral states: Directional, erratic, attraction and evasion to divers. We modeled the sequence of behaviors exhibited by manta rays via first order Markov chains. Our models accounted for passive and active diver behavior when modeling the changes in manta behavior. Manta rays in Banderas Bay and Revillagigedo displayed a higher frequency of erratic behaviors than at Isla Contoy, while Banderas Bay manta rays transitioned to evasion behaviors more often. Manta rays responded similarly in both sites to active divers. At freediving sites, manta rays from Isla Contoy displayed evasion less frequently than at Banderas Bay. Changes in manta ray behavior were similar for both sites, but mantas in Banderas Bay transitioned to evasion more with active divers. The increased food availability for Isla Contoy manta rays could be the reason for the reduced response toward divers in this site. The existence of additional stressors such as both traffic in Banderas Bay could be causing the mantas in this site to respond more frequently to active divers. This study, the first of its kind in oceanic and Caribbean manta rays, highlights that regulations and the use of best practices are vital for achieving longer and less disturbing encounters for both manta rays and divers.

Understanding Diver Behavior on Underwater Cultural Heritage: Enriching the Observation Record Using Video Methods

Successful underwater heritage management requires a sound understanding of visitor behavior. Primary visitors to underwater heritage sites are divers whose behavior can pose risks to the integrity of site cultural heritage and tourism values. This study seeks to understand wreck diver in-water behavior. Conventional observation of diver behavior is limiting. Wearable cameras are becoming popular across many recreational activities and potentially expand the scope and quality of diver observation. Video observation is rarely used in such research. This article demonstrates the potential of video observation, describing the analysis of first-person video records to explore details of diver behavior on shipwrecks. The evidence demonstrates that while most divers behaved responsibly, a few contributed to most contact behaviors. The analysis details this behavior, identifying, for example, that deliberate holding and touching comprised most contacts. Such findings on diver behavior inform heritage and tourism management decisions and provide a baseline for future studies. Methodologically, the study demonstrates the power of this method of observing divers and other recreationists. This is particularly valuable for researching recreationalists in confined spaces, such as caves or shipwrecks. The quality of results allows for further evidence-based examination of motivations, values, intentions and meanings underlying observed diver behavior.

Scuba divers' attitudes towards responsible behaviour and profile

Within the global tourism industry exists the niche sector of alternative tourism, which includes adventure tourism. A sub-category of adventure tourism is self-contained underwater breathing apparatus (Scuba diving). The goal of this study was to identify how a scuba diver’s underwater behaviour is related to a set of predisposing characteristics. This study used a quantitative research approach rooted in the theory of positivism to explain scuba diving tourism within a South African context. A comprehensive literature review exploring the uniqueness of adventure tourism and scuba diving and the importance of coral reefs within marine protected areas (MPAs) is presented. In addition to the literature review, an online survey was conducted among South African divers (n=137). The survey aimed to determine the divers’ level of specialisation, environmental awareness, and demographic information. The findings indicated that while the respondents were generally evenly distributed demographically, their experience and environmental awareness improved the longer they were involved in scuba diving. Respondents were observed to be generally responsible divers and to have a broad understanding of the coral reef ecosystem. These findings support existing studies conducted at dive sites across the world, which indicate that responsible diver behaviour increases with the level of specialisation.

Diving under the radar: divers and submerged aircraft

ABSTRACT Recreational scuba diving has grown over the past six decades and interest in wreck diving has increased. This growth demands evidence-based management, and understanding diver behaviour is crucial to effective management. This paper presents the first formal study of diver behaviour on a particular class of underwater cultural heritage, World War II submerged aircraft at Chuuk Lagoon in the Federated States of Micronesia. Chuuk is a world-renowned dive tourism destination, providing divers access to an extensive collection of shipwrecks and a few submerged aircraft. Although it may be assumed that diver behaviour on shipwrecks and aircraft would be similar, this study identifies marked differences in diver behaviour between the two different types of wrecks. This may be due to their novelty or to their scale. The smaller and more human scale of aircraft may encourage tactile interaction, such as sitting in the cockpit. Restricted physical access increases the chances of accidental damage to the aircraft. The implication of these findings is that there are different needs for the management of shipwreck and aircraft diving, to protect both cultural heritage and dive tourism values of sites.

Coral damage by recreational diving activities in a Marine Protected Area of India: Unaccountability leading to ‘tragedy of the not so commons’

Globally, coral reefs have drastically degraded due to local and global environmental stressors. Concurrently, coral reef tourism is rapidly growing in developing economies, which is one of many anthropogenic stressors impacting reefs. At the Malvan Marine Sanctuary, a Marine Protected Area (MPA) on the West coast of India, we investigated the impact of recreational diving on the reef from 2016 to 2019. To evaluate the diver's underwater behavior, a novel approach was used, wherein the video-log broadcasting website www.youtube.com was perused. Evidential proof substantiates heavy physical damage to corals because of recreational diving activity, which may lead to the collapse of coral habitat if it continues unabated. This resource depletion ironically elevates the economy of dependents averting consequences due to lost corals, thus making this a ‘tragedy’ for corals which are not meant to be ‘commons’. The study asserts need for proactive conservation efforts with stringent implementation and restoration initiatives in this MPA.

Diving and mental health: the potential benefits and risks from a survey of recreational scuba divers.

Scuba diving is physically and cognitively demanding. Medical guidance regarding physical and mental health (MH) issues and related prescribed medication is often based on limited evidence. There is a paucity of data concerning diving with MH issues. This survey aimed to investigate the prevalence of MH issues and use of prescription medications among United Kingdom (UK) sport divers, and the rate of non-compliance with current guidance among divers suffering depression and anxiety. The positive effects of scuba diving on MH were also considered. An anonymous online survey was publicised through diving exhibitions and social media. Measures included diver and diving demographics; GAD-7 Anxiety and PHQ-9 depression questionnaires; diagnosed current and/or past MH conditions; medication usage; comorbid medical conditions/treatments; disclosure of past/current MH issues; and perceived MH benefits of diving. Data from 729 respondents revealed MH issues at rates comparable with the general population. Current and/or past MH issues were reported by 111/729, with 60 having active diagnoses, and 45/60 taking prescribed psychotropic medications; 21/45 did not declare their medication on diver self-certification medical forms. The activity of diving was thought to be beneficial to MH by 119/729 respondents. Divers experienced expected levels of MH issues, but did not comply with current medical guidelines on modifying or abstaining from diving activity or reporting their MH condition. Changes may be needed to diver training to encourage more accurate reporting and aid development of evidence-based protocols. Guidelines could be reconsidered in light of current diver behaviour, risks and potential MH benefits.

Integration of Ensemble and Evolutionary Machine Learning Algorithms for Monitoring Diver Behavior Using Physiological Signals

The level of consciousness and the concentration of drivers while driving play a vital role for reducing the number of accidents. In recent decade, in-vehicle infotainment (IVI) [or in-car entertainment (ICE)] is one of the main reasons that lead to degradation of drivers performance and losing awareness. However, the impacts of some other reasons, such as drowsiness and driving fatigue, are entirely important as well. Hence, early detection of such performance degradation using different methods is a very hot research domain. To this end, the data set is collected using two different simulated driving scenarios: normal and loaded drive (17 elderly and 51 young/35 male and 33 female). This paper, therefore, concentrates on driving performance analysis using various machine learning techniques. The optimization part of the proposed methodology has two main steps. In the first step, the performances of the K-nearest neighbors (KNN), support vector machine (SVM), and naive Bayes (NB) algorithms are improved using bagging, boosting, and voting ensemble learning techniques. Afterward, four well-known evolutionary optimization algorithms [the ant lion optimizer (ALO), whale optimization algorithm (WOA), particle swarm optimization (PSO), and grey wolf optimizer (GWO)] are applied to the system for optimizing the parameters and as a result enhance the performance of whole system. The GWO-voting approach has the best performance compared to other hybrid methods with the accuracy of 97.50%. The obtained outcomes showed that the proposed system can remarkably raise the performance of the classical algorithms used.

The panic triangle: onset of panic in scuba divers

Panic arising from physical or psychological stress is a common issue in reported incidents and accidents in scuba diving. Due to its effect on perception, thinking and diver behavior, the panic reaction is often a significant factor in the generation or escalation of problems, potentially leading to injuries and fatalities. The instinctive behaviors associated with panic are incompatible with the constraints of scuba diving (e.g., flight response to threat, leading to rapid ascent). Although the dangers are well known, the psychological mechanisms of panic and the implications for prevention/risk reduction are not sufficiently highlighted to recreational divers. In applied psychology, there are grounded theoretical models which describe the onset and maintenance of anxiety and panic, and an evidence base for approaches to anxiety management. For example, these models are used within structured psychological approaches for people experiencing anxiety disorders; and panic attacks are resolvable. Based on these models and underlying theory, this article proposes a new, accessible model for panic in divers. The potential uses of the model are to: (1) provide a simple framework for divers to understand the onset of panic; (2) promote the need for adequate training; (3) describe the importance of staying within training standards, qualifications and personal limitations; (4) support diver and dive educator understanding of individual factors in panic reactions (e.g. psychiatric conditions) placing greater emphasis on psychological fitness to dive; and (5) draw attention to approaches to improved regulation of emotion and promote individual responsibility.

Are there economic benefits from marine protected areas? An analysis of scuba diver expenditure

In 1998, the Italian authorities declared the marine area around the Peninsula of Portofino, Liguria, a Marine Protected Area (MPA) covering 13 km of coastline on the north-western coast of Italy. Thus, many feared decreased local tourism and resultant economic loss due to limitations on activities within the MPA. The MPA has, however, led to an increase in scuba in the area. This research evaluates the importance of scuba divers as a source of tourism and income for the local economies surrounding the Portofino MPA. Research indicates that spending is a better criterion for analysis than numbers of visitors to an attraction or area. Therefore, understanding spending behaviour is important in influencing the benefits derived from scuba diving tourism. While scuba diving is a popular activity worldwide and a drawcard for many destinations, little research analysing their spending behaviour is available. This research was conducted at the Portofino MPA, Italy, where more than 700 questionnaires were completed during June/July 2016 with the assistance of eight of approximately 20 diving operators in the area. The results provide dive operators and the destination marketing organisation with information on specific market segments and insight into the spending behaviour of divers.

Scuba diving and sedentary fish watching: effects of photographer approach on seahorse behavior

ABSTRACTScuba diving tourism represents a growing non-extractive use of the marine environment, being an important income source for coastal communities. However, the activity can cause impacts on benthic sessile organisms by abrading tissues or breaking physical structures. The effects of scuba diving on fishes are less studied and there is no consensus about the impacts caused. We investigated if scuba divers are causing behavioral disruptions on seahorses. Divers using and not using cameras were observed while watching seahorses. We recorded the minimum distance that divers approached, the duration of interaction and physical contacts with seahorses, and the behavioral response of seahorses. Divers using action cameras attached to an extension pole approached the seahorses more closely, causing significantly more behavioral disruptions (escape) and physical contact with them. These repeated behavioral disruptions may negatively impact seahorse habits, such as feeding, reproduction, and resting. To mitigate the potential impacts on seahorses, we recommend the establishment of a minimum approach distance of 36 centimeters, the use of a pre-dive briefing to reinforce low-impact diving techniques, and close supervision by dive leaders to ensure appropriated in-water diver behavior.

Personality and behavioural outcomes in diving: current status and recommendations for future research.

This paper provides a brief overview of the shift from studies describing the personality profiles of divers to studies exploring associations between personality variables and diving performance in terms of behavioural outcomes. The personality associations that were investigated include performance during training, panic proneness, diving injuries, susceptibility to inert gas narcosis, and the behaviour of tourist divers. The paper concludes with a number of suggested directions for further research on personality and diving that may provide tangible benefits in terms of both enhanced safety and improved performance underwater.

Using an educational video-briefing to mitigate the ecological impacts of scuba diving

ABSTRACTRecreational scuba diving is rapidly increasing, and the negative impacts to marine reef biota are of conservation concern. Educational approaches have been tested to mitigate diver damage to benthic organisms, but logistical constraints impede their implementation in many locations. We investigated the behaviors of scuba divers in terms of their contacts with benthic organisms, and assessed how an educational video-briefing caused changes in diver behavior. The video provided environmental information to divers, and enhanced their use of low-impact diving techniques. Divers who received the video-briefing exhibited significantly lower rates of contact with and damage to the benthos, than did divers who did not receive a briefing. The level of diving experience did not correlate with the rate of benthic contact in either group of divers. Male divers and photographers both contacted the benthos significantly less, and female divers and photographers both caused significantly less damage when they viewed the video-briefing prior to diving. Our findings highlight the importance of easily implemented, standardized educational approaches such as the use of video-briefings to mitigate the impacts of scuba diving. This study adds to the framework of tested strategies available to support the sustainable use of marine areas by the diving tourism industry.

Recreational Diving Impacts on Coral Reefs and the Adoption of Environmentally Responsible Practices within the SCUBA Diving Industry.

Recreational diving on coral reefs is an activity that has experienced rapidly growing levels of popularity and participation. Despite providing economic activity for many developing coastal communities, the potential role of dive impacts in contributing to coral reef damage is a concern at heavily dived locations. Management measures to address this issue increasingly include the introduction of programmes designed to encourage environmentally responsible practices within the dive industry. We examined diver behaviour at several important coral reef dive locations within the Philippines and assessed how diver characteristics and dive operator compliance with an environmentally responsible diving programme, known as the Green Fins approach, affected reef contacts. The role of dive supervision was assessed by recording dive guide interventions underwater, and how this was affected by dive group size. Of the 100 recreational divers followed, 88 % made contact with the reef at least once per dive, with a mean (±SE) contact rate of 0.12 ± 0.01 per min. We found evidence that the ability of dive guides to intervene and correct diver behaviour in the event of a reef contact decreases with larger diver group sizes. Divers from operators with high levels of compliance with the Green Fins programme exhibited significantly lower reef contact rates than those from dive operators with low levels of compliance. The successful implementation of environmentally responsible diving programmes, which focus on influencing dive industry operations, can contribute to the management of human impacts on coral reefs.

The effects of SCUBA diving on the endemic Mediterranean coral Astroides calycularis

Many papers have dealt with the impact of diving activities, although most have been focussed on divers' physical contact and their equipment. Nevertheless, there are more factors that may be affecting the benthic community, for example, environment, diver's behaviour, dive characteristics, or previous knowledge of the diver about the surrounding wildlife. In the present study, several factors have been studied that may affect the orange coral (Astroides calycularis) populations in the North Alborán Sea (Mediterranean Sea). It has been demonstrated that detached colonies are more common in an impacted station than in a controlled station. However, larger sized detached colonies were found in the controlled station, which is probably due to the species growing without impact factors until they reach a size that they become detached naturally. Dimensions studied such as characteristics of dives, diver experience, environmental perception, or previous knowledge of divers are affecting at the endangered orange coral, showing that the characteristics of dives is a more noteworthy dimension. But this, in synergy with other factors, may be the cause of losing colonies. The results of this study are helpful to the managers of marine environment and MPAs, especially where sensitive species are present during diving activities. Therefore, essential diver education programmes must teach the environmental value and the fragility of different species. Protecting these populations should be a high priority of the environment managers to preserve our natural heritage.

Recreational Diver Behavior and Contacts with Benthic Organisms in the Abrolhos National Marine Park, Brazil.

In the last two decades, coral reefs have become popular among recreational divers, especially inside marine protected areas. However, the impact caused by divers on benthic organisms may be contributing to the degradation of coral reefs. We analyzed the behavior of 142 scuba divers in the Abrolhos National Marine Park, Brazil. We tested the effect of diver profile, reef type, use of additional equipment, timing, and group size on diver behavior and their contacts with benthic organisms. Eighty-eight percent of divers contacted benthic organism at least once, with an average of eight touches and one damage per dive. No significant differences in contacts were verified among gender, group size, or experience level. Artificial reef received a higher rate of contact than pinnacle and fringe reefs. Specialist photographers and sidemount users had the highest rates, while non-users of additional equipment and mini camera users had the lowest contact rates. The majority of contacts were incidental and the highest rates occurred in the beginning of a dive. Our findings highlight the need of management actions, such as the provision of pre-dive briefing including ecological aspects of corals and beginning dives over sand bottoms or places with low coral abundance. Gathering data on diver behavior provides managers with information that can be used for tourism management.

Artificial Reef Attributes and The Relationship With Natural Reefs: Evidence From The Florida Keys

Natural or coral reefs represent extremely valuable ecosystems supporting an estimated 25 percent of all marine life, yet recent reports suggest that 75 percent of the world’s natural reefs are under threat from both natural and human stressors. In areas such as the Florida Keys that boasts an expansive mix of natural and artificial reefs, recreational diving on the system provides an important economic contribution to the local community but also potentially contributes to the stress of the existing natural reef system. We develop a revealed and stated preference modeling framework of diver behavior and find that deployment of an additional large ship reef increases overall diving activity but does not impact diving behavior on the natural reef system.