Spear Fishing Research Articles

A comparative analysis between recreational and artisanal fisheries in a Mediterranean coastal area

AbstractThe biological impact and the social characteristics of different artisanal (professional) and recreational fishing techniques on the marine resources of a coastal Mediterranean area were compared. Data were from artisanal and recreational surveys carried out between 2006 and 2010. Competition between recreational (particularly spear fishing) and artisanal fishers for the natural resources is important as 52% of the 98 species surveyed were caught by both types of fishers. A total of 87 species were caught by all artisanal fishing gears together (of which 84% were retained and 16% discarded). Recreational fishing caught 58 species of which none was systematically discarded. The two fishing techniques that raise major environmental concerns are spear fishing (very selective in terms of species and/or sizes and high intrinsic vulnerability of catches) and trammel netting (highest number of species discarded and highest number of species endangered). Important challenges from the social standpoint were found that need to be taken into account in the management of coastal fisheries in the Mediterranean Sea including: progressive disappearance of the artisanal fisheries, ageing of the artisanal fisher populations and decline in the number of fishing gears used by artisanal fishers.

Rez Life: An Indian's Journey through Reservation Life

Sándor Szathmári Voyage to Kazohinia Inez Kemenes, tr. New Europe Books In the style of Gulliver’s Travels, Voyage to Kazohinia chronicles the adventures of an English surgeon in Kazohinia, land of the sterile Hins and their emotional counterparts, the Behins. Completed on the eve of World War II, this dystopian satire is a classic of Hungarian literature. Nota Bene reality of becoming emerged. This new reality of becoming was the light in the wilderness, and it generated its own meaning and took hold. A new sanctuary emerged in the wilderness, which still continues to shed its light. Dalia R. Daniel Stanford, California David Treuer. Rez Life: An Indian’s Journey through Reservation Life. New York. Atlantic Monthly Press. 2012. isbn 9780802119711 The cover of David Treuer’s newest book, Rez Life: An Indian’s Journey through Reservation Life, evokes the tough but rewarding work of gathering wild rice on what could be one of many Ojibwe reservations throughout Minnesota and Wisconsin. The photo is an apt choice because the same words that define the picture also describe his text. With a historian ’s attention to detail, a documentarian ’s keen eye, a novelist’s wit, and a son’s love, Treuer takes readers home to northern Minnesota. What begins as a visit to his reservation , Leech Lake, evolves into a forceful and memorable critique of the people and policies that contribute to the modern reality of reservation life throughout the United States. Treuer’s book includes many tales of loss and despair. He describes the suicide of his grandfather or the drug overdose, rape, and murder of a young girl at one of the neighboring reservations; however, Rez Life is far more than a collection of horror stories. Instead, it reads as a tour de force for those interested in key pieces of federal policy that created reservations and their famously poor conditions . Treuer covers more in three hundred pages than most Native Studies courses do in a semester. While academics will find Treuer ’s work satisfying and concise, his text is successful because legislation is always secondary to interpersonal relationships. For example, instead of rehashing well-worn stories about battles over spear fishing, Indian gaming, or sovereignty, Treuer turns to other voices to help him solidify his arguments regarding these topics . He calls upon his mother and her experiences as a tribal court judge, his father and his time working for the federal government, and a tribal police officer at Red Lake reservation, among others. Each of their stories wraps around Treuer’s until the reader cannot help but notice how much he depends on these people to shape his vision of place. Treuer makes his living as a professor, but this book proves that he is more than just a scholar, with a passion for his people and their language. In chapter 6, Treuer embarks on an extended discussion of the importance of language revitalization . He chronicles the work being done at an Ojibwe language immersion school in northern Wisconsin as he also contends that much of the beauty of reservation life exists and will continue only if Native people commit to language preservation. At the outset of Rez Life, David Treuer says that he owes much to his family and his people. I think those who owe David Treuer the greatest debt are his readers. Although his sharp humor and sarcasm might be off-putting at times, in the end, Treuer’s book is a balanced meditation on reservation life that belongs on the shelves of serious scholars and avid readers alike. Sarah J. O’Connell University of Oklahoma STATEMENT OF OWNERSHIP, MANAGEMENT, AND CIRCULATION 1. Publication Title: World Literature Today 2. Publication Number: 060-680 3. Filing Date: September 1, 2012 4. Issue Frequency: Bimonthly 5. Number of Issues Published Annually: Six 6. Annual Subscription Price: $25 Individual, $130 Institution 7. Complete Mailing Address of Known Office of Publication: World Literature Today / University of Oklahoma / 630 Parrington Oval, Suite 110 / Norman, OK 73019-4033 8. Complete Mailing Address of Headquarters of General Business Office of Publisher: World Literature Today / University of Oklahoma / 630 Parrington Oval, Suite 110 / Norman, OK 73019-4033 9. Full...

Assessing the impact of spear fishing by using competitions records and underwater visual censuses

Recreational fishers are increasingly competing for space and resources with commercial fishers worldwide, but have been poorly studied. In particular, the impacts of spearfishing competitions on the temperate fish assemblages have seldom been analysed. In Galicia (NW Spain), there are currently 5000 spear fishers, and 500 of them participate in spearfishing competitions. An historic archive of spearfishing competitions was used to assess their influence on the subsequent competitions in the area and to analyse their effect on the fish abundances estimated by underwater visual censuses. The annual recreational catch of the spear fishers was also estimated and comparisons with the commercial landings were performed. The spear fishers targeted 29 species, although six accounted for 95% of the catch. Most of the species show low vulnerabilities to fishing pressure and only Dicentrarchus labrax, among frequently caught species, can be considered as moderately vulnerable. The overall impact of spearfishing competitions on fish populations was limited, although some competitions temporarily reduced the abundances of Labrus bergylta, the main target species, by up to 83%. Spear fishers caught a large proportion of the total catch of common species, with recreational catches of some species (e.g. L. bergylta) matching or exceeding the commercial catch. The inclusion of this fishery in the management models of the coastal ecosystems is strongly recommended

Biological implications of recreational shore angling and harvest in a marine reserve: the case of Cape Creus

Abstract Recreational shore fishing along the coast of the marine reserve of Cap de Creus (NW Mediterranean) was studied in 2007 and 2009 based on roving creel surveys (on‐site angler surveys during which anglers' harvests are examined by the survey clerk). The study aimed to assess the biological impacts of this leisure activity on coastal fish stocks and the potential risks arising from the use of exotic baits. Recreational shore fishers employ seven different fishing techniques, of which the bottom fishing rod (a fishing rod whose hooks, together with the bait, lie on the bottom or near it by means of a heavy weight) is by far the most widely used method (nearly 90% of observations). In total, 25 fish species were identified in the catch from the bottom fishing rod. The estimated annual shore fishing catches (c.3 tons) are much lower than those obtained by recreational boat and spear fishing (c.20 tons each), and those from commercial (artisanal) fishing (c.50 tons). The weighted mean vulnerability index and trophic level values in the catch from the bottom fishing rod are 52.2 and 4.03, respectively. A minimum of 43% of the baits used by the shore anglers were live, non‐native species (mostly polychaetes). Overall, results highlight the impact of shore angling on coastal fish communities of a protected area and the increasing environmental risks arising from the use of exotic marine baits, which constitute a potential and unregulated vector of introduction of non‐native species in the Mediterranean. Copyright © 2011 John Wiley & Sons, Ltd.

Effects of Customary Marine Closures on Fish Behavior, Spear-Fishing Success, and Underwater Visual Surveys

Customary management systems (i.e., management systems that limit the use of marine resources), such as rotational fisheries closures, can limit harvest of resources. Nevertheless, the explicit goals of customary management are often to influence fish behavior (in particular flight distance, i.e., distance at which an organism begins to flee an approaching threat), rather than fish abundance. We explored whether the flight distance of reef fishes targeted by local artisanal fishers differed between a customary closure and fished reefs. We also examined whether flight distance of these species affected fishing success and accuracy of underwater visual census (UVC) between customary closed areas and areas open to fishing. Several species demonstrated significant differences in flight distance between areas, indicating that fishing activity may increase flight distance. These relatively long flight distances mean that in fished areas most target species may stay out of the range of spear fishers. In addition, mean flight distances for all species both inside and outside the customary-closure area were substantially smaller than the observation distance of an observer conducting a belt-transect UVC (mean [SE]= 8.8 m [0.48]). For targeted species that showed little ability to evade spear fishers, customary closures may be a vital management technique. Our results show that customary closures can have a substantial, positive effect on resource availability and that conventional UVC techniques may be insensitive to changes in flight behavior of fishes associated with fishing. We argue that short, periodic openings of customary closures may allow the health of the fish community to be maintained and local fishers to effectively harvest fishes.

Don't hold your breath: anoxic convulsions from coupled hyperventilation–underwater breath‐holding

Clinical record We report anoxic convulsions occurring in two medical students competing in a breath-hold dive competition in shallow water. The seizure-like activity occurred during a competition called the Dolphin Dive, which was part of a university medical school swimming function. The goal set for the competitors was to swim as far as possible underwater in a swimming pool without taking a breath. Three students participated in the event and two students had convulsions. In both cases, the students hyperventilated before the dive. Student 1 A 27-year-old man, with a past medical history of asthma, had been involved in underwater hockey and spear fishing, and was previously able to underwater breath-hold for 2 minutes while keeping still. During the competition, he swam about 60 metres and spent 40 seconds underwater. After the dive, he stood up in the water, lost consciousness and was witnessed to have multifocal myoclonic jerks lasting about 1 minute. He recalled some jerking of the limbs when asked afterward. Student 2 A 27-year-old man, with no significant past medical history, had previously swum at national championship level and had worked as a surf lifesaver. He reported swimming about 85 metres for the competition and spending 90 seconds underwater. At the end of his dive, he became unconscious, floated to the surface of the pool and had multifocal myoclonic jerks lasting less than 1 minute. He had no recollection of the convulsive movements. Many people were observing the race and so the students were rapidly retrieved from the pool; they regained consciousness and did not experience any long-term consequences.

Threatened fishes of the world: Mycteroperca bonaci (Poey, 1860) (Serranidae: Epinephelinae)

Common names: Black grouper, badejo-quadrado. Conservation status: High vulnerable by the IUCN Red List and in Brazil it was included in the “commercially extinct” list of marine resources in Sao Paulo State (Sao Paulo 2008). Identification: D XI + 15–17; A III +11–13; LL 78–83. The body has 7 or 8 columns of rectangular dark gray blotches. The outer third of the second dorsal, anal and caudal fins are black, edge of preopercle is smooth, without a pronounced lobe in the angle. The maximum length is 133 cm, with maximum body weight of 65 kg (Rocha and Costa 1999). Illustration from FAO species catalogue. Distribution: This species occurs in western Atlantic, from Bermuda and Massachusetts to southern Brazil, including the southern part of Gulf of Mexico, Florida Keys, Bahamas, Cuba and the Caribbean. Habitat and ecology: This species is found on rocky bottoms and coral reefs to depths of at least 75 m. Adults are most commonly found bellow 30 m while juveniles generally occur in shalow waters. Adults feed primarily on fishes and juveniles prey, mainly crustaceans. The black grouper is one of the most important species in Atlantic coast fisheries. In Northeast Brazil, between the States of Ceara and Alagoas, M. bonaci has been caught by artisanal fishery using hooks and lines or compressor-assisted spear fishing (Teixeira et al 2004). Reproduction: This specie is a protogynous hermaphrodite, with reproductive aggregations. Maturing females occur between 50 and 100 cm and mature males between 96 and 116 cm (Heemstra and Randall 1993). Threats: Overfishing. Conservation action: Since 2003, in Brazil a minimum capturing size of capture was established at 45 cm. Conservation recommendation: Environ Biol Fish DOI 10.1007/s10641-010-9634-9

Spatial and fishing effects on sampling gear biases in a tropical reef line fishery

Biased estimates of population parameters for harvested stocks can have severe implications for fishery management strategy choices. Hook-and-line fishing gear is size-selective and therefore collects biased samples from wild populations. Such biases may also vary in space and time. To assess this assertion, we compared line- and spear-caught samples of the main target species of an Australian hook-and-line fishery to quantify relative bias in size and age structure estimates. We also assessed the consistency of biases among four fishery regions and between two management zones – areas open and closed to fishing. Fish less than 310 mm and younger than 4 years comprised a larger proportion of the speared than the line samples regardless of region or management zone. Conversely, hook-and-line sampled more fish in larger size classes (>370 mm) and older age classes (≥6 years) relative to spear fishing. These biases were qualitatively, but not quantitatively, consistent in all regions and management zones. This variation in sampling resulted in different inferences about regional and zone-related patterns in population size and age structure. We recommend careful consideration of sampling bias when drawing conclusions about regional and management zone effects on fish populations.

Age, growth, sexual maturity and food composition ofSciaena umbrain the south-eastern Black Sea, Turkey

Summary Studied were the age, growth, maturity and food composition of the brown meager, Sciaena umbra, caught off Trabzon, south-eastern Black Sea (Turkey) in 2002–2003. A total of 329 individuals was collected by spear fishing and hand nets. The thin sectioning method was used for aging the fish otoliths. Fitted von Bertalanffy growth parameters for all fish were: L¥ = 51.14 (±1.19) cm, k = 0.27 (±0.02) year )1 and t0 = )0.93 (±0.07) year. This study revealed that S. umbra is a relatively slow-growing and longlived species with a life span in excess of 18 years. Sexual maturity begins when they reach a length of about 15 cm. Lengths at which 50% of brown meagre become mature are 19.50 for males and about 22 cm for females. Spawning begins in June, when the temperature is approximately 18� C, and ends in August. Gut content analysis indicated that this species feeds mainly on crustaceans, then switches to fish as they grow. Sciaena umbra appears to be an apex predator in the upper littoral zone.

Acceptance of the 2009 Henry Baldwin Ward Medal: The Accidental Parasitologist

Acceptance of the 2009 Henry Baldwin Ward Medal: The Accidental Parasitologist

Bite by moray eel

Injuries caused by moray eels are not a common problem, but are distributed throughout the globe, affecting mainly fishermen while manipulating hooked or netted fish. On a lesser scale, scuba divers and snorkelers, practicing or not spear fishing, are occasional victims of bites. With more than 185 species distributed among 15 genera, mostly in tropical to temperate shallow water, moray eels easily come into contact with humans and occasional injuries are not uncommon. The current study reports one case of moray eel bite and discusses the circumstances in which the accident happened, as well as wound evolution and therapy.

Walleye warriors and white identities: Native Americans’ treaty rights, composite identities and social movements

During the late 1980s and early 1990s white supremacist vigilantes attacked Native American spear fishers attempting to exercise treaty rights in northern Wisconsin. Nearly a decade later, Native Americans organized a coalition that included some of their former white supremacist enemies to stop plans by transnational corporations to pursue environmentally harmful resource exploitation enterprises in the region. Native Americans and their allies had to respond to corporate promoted ‘new right’ white identities to defend themselves in the spearfishing struggle by creating new counter-hegemonic racial identities for their enemies and themselves. Their experiences show how regressive and progressive racial identities become formed through struggle and how struggles over racial identities can help generate a broader movement for social justice.

マングローブ林とサンゴ礁が併存する島嶼沿岸域の漁業と海洋環境

This research was carried out in 2005 and 2006 in the coastal area of eastern Viti Levu, Republic of the Fiji Islands, where coral reefs and mangrove forests coexist. The aim is to study the relationship between the marine environments, the biodiversity of marine industrially important species and the fisheries at the community level. Twenty one families, 22 genuses, 33 species of fish and 8 families, 9 genuses, 11 species of mollusks were caught by the local people in this area. Salinity in the mangrove area was lower than in the coral reef area. Carbon-based biomass and its composition in the zooplankton community were also different in both areas. Fishing methods used were net fishing, hand line fishing, and spear fishing for fish and gleaning on the tidal flat to find a siphon of bivalve. In this area, traditional fishing techniques were used and the healthy natural environment conditions existed, and these might contribute to maintain the high biodiversity level of fish and mollusks. In the further sustainable use of coastal resources, community based resource management and ecosystem based co-management are important.

Growth, reproduction and recruitment patterns of the wide-eyed flounder, Bothus podas Delaroche (Pisces: Bothidae), from the Azores

The wide-eyed flounder, Bothus podas, occurs in many East Atlantic sub-tropical and temperate inshore areas and is the dominant flatfish in shallow-water areas around the Azores. The aim of this study was to examine the growth, reproductive biology and recruitment patterns of the wide-eyed flounder in the Azores. Adult fish samples were obtained by spear fishing and SCUBA hand netting at Faial Island. Juveniles were obtained from a complementary monthly beach-seining programme undertaken at Porto Pim Bay, Faial. Sex and development stage were determined by macroscopic examination of gonads, whereas age estimates were obtained by counting the number of opaque bands in the otoliths. In the Azores, B. podas reaches 6 years old, which is more than reported for the central Mediterranean, the only other population of this species that has been studied. The studied population has a sex ratio biased to males, which contrasts to a previous observational study, which noted a female-biased sex ratio. Spawning time, as determined from the gonadosomatic ratio and the macroscopic examination of gonads, was between July and September. This time period agrees with behavioural observations in the same area. Sexual maturity was estimated at a total length (TL50) of 14.1 cm and at an age (A50) of 1.7 years. Small juveniles occur on sandy inshore nursery areas for most of the year, but mainly between July and August each year. The presence of small fish throughout most of the year could suggest a protracted settlement period or slow growth on occasions on the shallow-water nursery grounds.

Artisanal fisheries production in the coastal zone of Itaipu, Niterói , RJ, Brazil

Artisanal fisheries in the coastal zone of Itaipu-RJ play an important role in the local market, but little is known about production and productivity of the fisheries. From April 2001 to March 2003, we monitored a total of 618 landings from the beach-seine (99), the gill nets ("corvineira" - 331, "linguadeira" - 40 and "rede alta" - 25), the hook and line (98), the squid jigging (17), and the spear fishing and trap fisheries (five and three, respectively). The total monitored production was 21866 kg and the catch per unit effort (CPUE) 35.4 kg.trip-1. Considering the number of effective fishing days and the average daily production per fishing gear, the annual production was estimated at 136687 kg (0.2% of the state's production in 2004). Predominant resources were: Micropogonias furnieri,Trichiurus lepturus, squids (Loligo spp.), clupeiform fishes (Sardinella brasiliensis, Cetengraulis edentulus, Pellona harrowerii and Harengula clupeola), Eucinostomus spp., Cynoscion spp., Menticirrhus spp., Caranx crysos and Selene setapinnis. The combined analysis using hierarchical and non-hierarchical classification methods, separated four fishing gears and five species groups, based on their similarity patterns, identifying gears that most effectively capture the different fish groups. The beach-seine was less selective and most productive fishery in the summer. The "corvineira" was the second most productive fishery with higher yields in the summer and fall. Catches of "linguadeira" included rays and Paralychthys spp., wherereas the "rede alta" caught primarily M. furnieri,Mugil spp. and sharks.

Stony corals in Dominica during the 2005 bleaching episode and one year later

In 2005, the Atlantic and Gulf Rapid Reef Assessment protocol (AGRRA v. 4) was implemented for the first time in Dominica between October 20 and November 18. During that time elevated sea surface temperatures were initiating the most severe bleaching episode so far recorded for the northeastern and eastern Caribbean. Nineteen of the 20 species of stony corals within the survey were affected. The occurrence of pale, partially bleached or completely bleached colonies exceeded 50% in 13 of these species, and 76 % of all colonies (n = 1475) had some symptom of bleaching. In an effort to assess the impact of this event on Dominica?s stony corals, the sixteen sites studied in 2005 were revisited in 2006 (October 17 ? November 25) and resurveyed using the same methods. Twenty of the 23 species within the survey were affected, yet the occurrence of pale, partially bleached or completely bleached colonies exceeded 50% in only four of these species. Twenty-six percent of all colonies (n = 1407) had some symptom of bleaching. However, live coral cover had decreased by 28%, recent mortality had increased by 10%, and the abundance of coral recruits had decreased by 65%. Agaricia agaricites was among the most affected species having been a common coral on Dominica?s reefs until 2005, yet absent in the 2006 survey. Deep sites (6-18m) were more affected by recent coral mortality than shallow sites, undermining the extent to which they may serve as refugia. The 2005 bleaching episode in Dominica followed those of 2003 and 2004. Given the increasingly chronic nature of such events, and the common disturbances of sediment runoff (quarries, coastal development), contamination (solid waste, sewage, pesticides), and fishing (spear fishing, traps, seine nets), Dominica?s marginal reef systems are being exposed to an unprecedented load of stressors. This scenario highlights the urgency of immediate action in reducing local disturbances if the island?s coral reef resources are to have a chance of being conserved.

The effect of protection on fish populations in the Ses Negres Marine Reserve (NW Mediterranean, Spain)

This work is the result of a 3-year monitoring programme for assessing the effect that the Ses Negres marine reserve has had on fish populations. Species richness (based on fish species that are considered to be reserve effect indicators), and the size structure of 4 species vulnerable to angling and spear fishing were studied by visual censuses conducted both inside and outside the marine reserve. Analysis of fish populations inside the reserve showed a reserve effect (larger sizes, higher abundance and richer fish assemblages) when compared to the non-reserve sites, especially by the end of the study period. The results highlight the importance of marine reserves for the recovery of fish populations. Future management plans are discussed for this marine reserve.

Successful surgical treatment of spear wounds in a Hawksbill Turtle, Eretmochelys imbricata (Testudines: Cheloniidae)

Sea Turtles are frequently poached by spearing in the neck region and subsequently holding them alive until slaughter. Thus the ability of stranding networks to repair and rehabilitate these animals is of interest. Two Hawksbill Turtles, Eretmochelys imbricata, illegally collected by spear fishing 8 May 1993 were confis- cated by the Puerto Rico Maritime Police and referred to the Caribbean Stranding Network for rehabilitation (Case # NEPCH136). The lacerated cervical region of both animals was surgically repaired. One adult male turtle 67 cm in carapace length and weighing 46.8 km lacking additional injuries recovered and was released (flipper tags QQD915, QQD916). A juvenile female was 46.0 cm in carapace length and 15.2 kg in weight with additional injuries succumbed to bacteria (Proteus mirabilis and Serratia rubridea) infections despite treatment with ampicillin trihydrate. A necropsy found routine numbers and diversity of parasites that were reported elsewhere. This result demonstrates that speared sea turtles without further complications can be rehabilitated. Since this somewhat early surgery, new techniques have been developed to even more successfully manage

The impacts of spear and other recreational fishers on a small permanent Marine Protected Area and adjacent pulse fished area

I used shoreline creel surveys to quantify fishing activities in and around a small (0.34 km 2) Marine Protected Area (MPA) in Hawaii (Waikiki Marine Life Conservation District). Spear fishing and shoreline pole & line fishing (angling) were the dominant fishing activities at Waikiki. Spear fishing had a greater overall impact on reef fishes than shoreline pole & line fishing, accounting for 70% of the total reef fish harvest at Waikiki, despite accounting for only 25% of fishing activities observed. Fishing activities at Waikiki were unevenly distributed in space and time. The MPA experienced minor illegal fishing and was located between an area of high diurnal spear fishing effort and an area of generally low fishing effort. This pattern of fishing activities allows jacks and goatfishes to evade capture despite nightly excursions from the MPA into fished areas, and may partly explain why these fishes remain more abundant and larger inside the Waikiki MPA than in surrounding fished areas. Quantifying fishing activities at MPA sites can provide valuable insight into how these areas function, and this information can be used to improve MPA design and effectiveness.

Decompression Sickness Following Breath-hold Diving

Despite convincing evidence of a relationship between breath-hold diving and decompression sickness (DCS), the causal connection is only slowly being accepted. Only the more recent textbooks have acknowledged the risks of repetitive breath-hold diving. We compare four groups of breath-hold divers: (1) Japanese and Korean amas and other divers from the Pacific area, (2) instructors at naval training facilities, (3) spear fishers, and (4) free-dive athletes. While the number of amas is likely decreasing, and Scandinavian Navy training facilities recorded only a few accidents, the number of spear fishers suffering accidents is on the rise, in particular during championships or using scooters. Finally, national and international associations (e.g., International Association of Free Drives [IAFD] or Association Internationale pour Le Developpment De L'Apnee [AIDA]) promote free-diving championships including deep diving categories such as constant weight, variable weight, and no limit. A number of free-diving athletes, training for or participating in competitions, are increasingly accident prone as the world record is presently set at a depth of 171 m. This review presents data found after searching Medline and ISI Web of Science and using appropriate Internet search engines (e.g., Google). We report some 90 cases in which DCS occurred after repetitive breath-hold dives. Even today, the risk of suffering from DCS after repetitive breath-hold diving is often not acknowledged. We strongly suggest that breath-hold divers and their advisors and physicians be made aware of the possibility of DCS and of the appropriate therapeutic measures to be taken when DCS is suspected. Because the risk of suffering from DCS increases depending on depth, bottom time, rate of ascent, and duration of surface intervals, some approaches to assess the risks are presented. Regrettably, none of these approaches is widely accepted. We propose therefore the development of easily manageable algorithms for the prevention of those avoidable accidents.