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A study of human impact on the presence and behavior of sharks was carried out June to November 2008 at these Red Sea diving sites: Elphinstone Reef, Daedalus Reef, Big Brother Is., Small Brother Is., Zabargad Is., Rocky Is., and Habili Ali. A total of 194 hours of field observations was done; sharks were encountered during 110 of 138 dives. Eight species of sharks for a total of 292 specimens were recorded: whale shark Rhincodon typus (1 specimen), pelagic thresher shark Alopias pelagicus (12), silvertip shark Carcharhinus albimarginatus (1), grey reef shark Carcharhinus amblyrhynchos (61), silky shark Carcharhinus falciformis (2), oceanic whitetip shark Carcharhinus longimanus (123), whitetip reef shark Triaenodon obesus (5), scalloped hammerhead Sphyrna lewini (87). The frequency of encounters in Elphinstone Reef is considerably lower than in the other study areas. Presence of recreational divers was recorded during almost all the dives: 134 cases on the total of 138 dives, with a presence of a total of 971 boats and 15,601 divers. Both the mean number of divers and the mean number of boats recorded for each dive are higher for Elphinstone Reef than in the other study sites. In Elphinstone Reef the high number of boats is also widely distributed for the entire area, making it impossible for the sharks to avoid human presence. The massive human presence in Elphinstone Reef is negatively affecting the presence of sharks and may also increase the probability of attacks on humans occurring. The number and conduct of boats of divers and boats frequenting this site need to be regulated by appropriate rules. It is therefore urgently necessary for Elphinstone Reef to be declared a protected area.
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Ahmed M. Shawky, Alessandro De Maddalena
HUMAN IMPACT ON THE PRESENCE OF SHARKS
AT DIVING SITES OF THE SOUTHERN RED SEA, EGYPT
Riassunto. Impatto della presenza umana sugli squali nei siti d’immersione del Mar Rosso meridionale, Egitto.
Da giugno a novembre 2008 è stato condotto uno studio in merito all’impatto umano sulla presenza e sul compor-
tamento degli squali nei seguenti siti d’immersione del Mar Rosso: Elphinstone Reef, Daedalus Reef, Big Brother
Is., Small Brother Is., Zabargad Is., Rocky Is., and Habili Ali. È stato effettuato un totale di 194 ore di osservazione
sul campo; gli squali sono stati incontrati durante 110 immersioni su 138. Sono state registrate 8 specie di squali
per un totale di 292 esemplari: squalo balena Rhincodon typus (1 esemplare), pesce volpe pelagico Alopias pelagi-
cus (12), squalo dalle pinne orlate di bianco Carcharhinus albimarginatus (1), squalo grigio di barriera Carcharhi-
nus amblyrhynchos (61), squalo sericeo Carcharhinus falciformis (2), longimano Carcharhinus longimanus (123),
squalo dalle pinne bianche di barriera Triaenodon obesus (5), pesce martello smerlato Sphyrna lewini (87). La
frequenza di incontri a Elphinstone Reef è considerevolmente minore che nelle altre aree di studio. La presenza di
subacquei ricreativi è stata registrata durante quasi tutte le immersioni: 134 casi su un totale di 138 immersioni, con
una presenza in totale di 971 imbarcazioni e 15.601 subacquei. Sia il numero medio di subacquei che il numero medio
di imbarcazioni registrate durante ogni immersione sono più elevati a Elphinstone Reef che nelle altre aree di studio.
A Elphinstone Reef inoltre l’elevato numero di imbarcazioni è ampiamente distribuito sull’intera area, di conseguen-
za per gli squali è impossibile evitare la presenza umana. La massiccia presenza umana a Elphinstone Reef sta
influenzando negativamente la presenza degli squali e potrebbe anche far aumentare le probabilità che si verifi-
chino attacchi ad esseri umani. Il numero di imbarcazioni e di subacquei che frequentano quest’area e il loro compor-
tamento devono essere regolati da un codice appropriato. È pertanto necessario che Elphinstone Reef sia urgente-
mente dichiarata area protetta.
Summary. A study of human impact on the presence and behavior of sharks was carried out June to November 2008
at these Red Sea diving sites: Elphinstone Reef, Daedalus Reef, Big Brother Is., Small Brother Is., Zabargad Is., Rocky
Is., and Habili Ali. A total of 194 hours of field observations was done; sharks were encountered during 110 of 138
dives. Eight species of sharks for a total of 292 specimens were recorded: whale shark Rhincodon typus (1 speci-
men), pelagic thresher shark Alopias pelagicus (12), silvertip shark Carcharhinus albimarginatus (1), grey reef
shark Carcharhinus amblyrhynchos (61), silky shark Carcharhinus falciformis (2), oceanic whitetip shark Carcha-
rhinus longimanus (123), whitetip reef shark Triaenodon obesus (5), scalloped hammerhead Sphyrna lewini (87).
The frequency of encounters in Elphinstone Reef is considerably lower than in the other study areas. Presence of
recreational divers was recorded during almost all the dives: 134 cases on the total of 138 dives, with a presence of
a total of 971 boats and 15,601 divers. Both the mean number of divers and the mean number of boats recorded for
each dive are higher for Elphinstone Reef than in the other study sites. In Elphinstone Reef the high number of boats
is also widely distributed for the entire area, making it impossible for the sharks to avoid human presence. The
massive human presence in Elphinstone Reef is negatively affecting the presence of sharks and may also increase
the probability of attacks on humans occurring. The number and conduct of boats of divers and boats frequenting
this site need to be regulated by appropriate rules. It is therefore urgently necessary for Elphinstone Reef to be
declared a protected area.
Keywords: sharks, oceanic whitetip shark, Carcharhinus longimanus, Red Sea, Elphinstone Reef, Daedalus Reef,
human impact, divers.
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Boll. Mus. St. Nat. Venezia, 64: 51-62 (2013)
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INTRODUCTION
The Red Sea is a well-known area for its conspicuous presence of sharks (RANDALL,
1986). A total of 49 species of sharks occur in the area encompassing the Red Sea and the
Gulf of Aden (BONFIL & ABDALLAH, 2004). There are no scientific data about the ecological
significance of sharks in these areas. Also, the Red Sea has many locations with different envi-
ronmental conditions and reef structures. All these factors affect the distribution of different
species of sharks in the area. Conversely, human impacts negatively affect shark abundance
and behavior. A study of human impacts was conducted to create a solid scientific back-
ground on the occurrence of sharks in the Southern Red Sea.
We report the results of a program “Shark ecology and its sustainable use in the Southern
Red Sea, Egypt”, carried out in 2008 thanks to a grant from the PADI Project AWARE Foun-
dation (Europe). The project aims were to assess the presence of sharks and to study
shark/human interactions (fishing and diving activities) at different diving sites in the areas
of Marsa Alam (Elphinstone Reef) and far southern reefs and islands, Southern Red Sea,
Egypt (fig. 1), by means of underwater observations and data collection.
Specific goals of the project were: a) to assess the presence of different species of sharks
at different diving sites in the area of Marsa Alam (Elphinstone Reef) and far southern reefs
and islands; b) to assess the impacts on sharks, fishing and diving activities; c) to create
public awareness of divers at different diving centers along the Red Sea; d) to prepare a Code
of Conduct for divers encountering sharks; e) to create a management plan for Elphinstone
Reef and the surrounding areas with the view to establishing the first marine park for sharks
in the Red Sea.
In this article we focus on the human impact on the presence and behavior of sharks at
the diving sites. Results of other aspects of our study will be presented in future reports.
MATERIALS AND METHODS
The project was conducted over a five and half-month period, beginning on the 1st of June
and ending on the 15th of November 2008. The data were collected three times per week during
most of the study, and one or two times per week, from September to November. Two dives
per day were performed, early morning and afternoon. During the Safari week, there were
three dives per day (each month, one week’s field work was conducted on the Safari Trip).
A total of 194 hours of field observations was carried out. These 194 hours were divided as
follows per month: 58 hours in June, 27 in July, 40 in August, 22 in September, 34 in Octo-
ber and 13 in the first half of November.
The operations were conducted aboard a 35-metre Safari Boat supported by full naviga-
tional instruments, including GPS map, fish finder, echo-sounder, radar and satellite phone.
One researcher collected the data, accompanied by a dive guide of the Safari Trip’s team. No
chum or bait was used to attract the sharks to the boat. The sharks were instead located by
the experience of the diving team, who knows where and when these predators can be found
in the study area.
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Fig. 1. Map of the study area, showing the locations of shark observations.
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A form for collecting data in a standardized way was prepared. Data collected include:
shark species, number of sharks, date, time, location with latitude and longitude, distance from
shore, distance from reef, swimming depth, sea depth, weather conditions, sea state, current
direction, current strength, surface water temperature, estimated shark total length, shark sex,
shark’s distinctive features (such as a particular coloration pattern, scars, deformation, etc.),
shark behavior, presence of other animals in the proximity, name of the observer (when differ-
ent from the first author).
Sharks were photographed or filmed using a CANON Digital PowerShot A630, 8 Mega-
pixel for subsequent analyses of their morphology and, whenever possible, photoidentifica-
tion of the specimens occurring in the area.
Also, shark/human interactions in the area were studied. Data on the occurrence and
number of tourist boats and divers in the area was regularly collected, in order to understand
the direct impact that human presence may have on the occurrence of sharks in the study area.
For each shark observation, the number of boats and divers present on the site, and the time
of each encounter, was recorded. The number of divers includes both those who were diving
and those who were on boats at the time of the encounter. Additionally, data on shark fishe-
ries in the area, including direct fisheries for sharks, captures of sharks taken accidentally while
fishing for other species, and recreational fishing, were collected.
RESULTS
A total of 138 dives was done over a five and half-month period. Sharks were encounte-
red during 110 of these dives. The results of these observations are presented.
The species of shark was identified in all encounters. A total of eight species of sharks
was recorded: whale shark Rhincodon typus Smith, 1828, pelagic thresher shark Alopias pela-
gicus Nakamura, 1935, silvertip shark Carcharhinus albimarginatus (Rüppell, 1837), grey reef
shark Carcharhinus amblyrhynchos (Bleeker, 1856), silky shark Carcharhinus falciformis
(Müller & Henle, 1839), oceanic whitetip shark Carcharhinus longimanus (Poey, 1861),
whitetip reef shark Triaenodon obesus (Rüppell, 1837), scalloped hammerhead Sphyrna lewi-
ni (Griffith & Smith, 1834).
The total number of shark encounters is 110 and the total number of specimens observed
is 292; details for each species are summarized in table 1 and figure 2. Photographic and/or
filmed evidence of the shark was taken in 37 encounters.
The size of all sharks encountered was estimated (tab. 1). The size of all the specimens
recorded fall within the size range previously known for these species (COMPAGNO, 1984, 2001;
LAST & STEVENS, 2009).
A total of 138 dives with 194 dive hours was made; details for each visited site are summa-
rized in table 2.
The frequency of encounters (encounters/hour) was calculated for Small Brother Is.,
Daedalus Reef, Big Brother Is., and Elphinstone Reef (tab. 2, fig. 3). We did not calculate
the frequency of encounters for the remaining sites because of the scarce amount of time
spent at field observations for these locations.
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Tab. 1. Collected data for each shark species. A: Elphinstone Reef; B: Daedalus Reef, C: Small Brother Is.;
D: Big Brother Is.; E: Zabargad Is.; F: Rocky Is.; G: Habili Ali.
Fig. 2. Number of specimens observed for each shark species.
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Number of Number of Estimated Number of encounters per site
Species encounters specimens size
(110) (292) (TL, cm) A B C D E F G
Rhincodon typus 1 1 600 0010000
Alopias pelagicus 10 12 225-350 1423000
Carcharhinus 1 1 270 1000000
albimarginatus
Carcharhinus 28 61 120-250 6 3 12 6001
amblyrhynchos
Carcharhinus 2 2 280-300 1010000
falciformis
Carcharhinus 35 123 190-270 25 901000
longimanus
Triaenodon obesus 4 5 100-180 2011000
Sphyrna lewini 29 87 190-250 15 10 31000
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The frequency of specimens for site (specimens/hour) was calculated for Daedalus Reef,
Small Brother Is., Elphinstone Reef, and Big Brother Is. We did not calculate the frequency
of encounters for the remaining sites because of the scarce amount of time spent at field
observation for these locations.
Table 2. Collected data for each site.
Fig. 3. Frequency of shark encounters/hour for each site.
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Sites Dives Dive hours Encounters Encounters/ Specimens Specimens/ Mean Mean
(138) (194) (110) hour (292) hour of divers of boats
Elphinstone 73 120 51 0.42 159 1.32 128.42 8.53
Reef
Daedalus 27 31 26 0.84 73 2.35 105.74 6.11
Reef
Small 20 22 20 0.91 34 1.54 91.6 4.8
Brother Is.
Big 13 16 12 0.75 21 1.31 116.38 6.61
Brother Is.
Zabargad Is. 2 2 0 0
Rocky Is. 2 2 0 0
Habili Ali 1 1 1 5
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Only one whale shark and one silvertip shark were observed. Pelagic threshers occurred
singly or in pairs. Grey reef sharks occurred both singly and in groups of up to 5 individuals.
Silky sharks occurred singly. Oceanic whitetip sharks occurred both singly and in groups of
up to 11 individuals. Whitetip reef sharks occurred singly or in pairs. Scalloped hammerhead
sharks occurred both singly and in groups of up to 10 individuals.
The presence of recreational divers was recorded during almost all the dives: 134 cases
on the total of 138 dives. The number of boats on the site, and therefore in the immediate
proximity of the sharks, ranged from 1 to 23 boats. The presence of a total of 971 boats and
15,601 divers (mean of 16.07 divers per boat) was recorded during the total of 138 dives,
for a mean of 7.04 boats and 113.05 divers per dive. The mean of divers and the mean of
boats recorded for each dive were calculated for Elphinstone Reef, Big Brother Island,
Daedalus Reef, and Small Brother Island (tab. 2, fig. 4). We did not calculate the frequency
of encounters for the remaining sites because of the scarce amount of time spent at field
observations for these locations. The maximum human presence was recorded at 10:00 am,
on October 22, 2008, in Elphinstone Reef, when 19 boats and 7 speed boats carrying a total
of 380 divers, were observed at the same time four C. longimanus were seen swimming in
the area.
The behavior of sharks at the diving sites was analyzed. The whale shark swam very
slowly and most of the time in one direction. When several of the divers approached the
shark, it turned its head slowly at a small angle to change its direction with a little stroke
of its caudal fin. With the increasing number of divers around it, the shark dove to a few
meters down (10-14 m), keeping its distance from the divers. The shark would then ascend
once again to the surface, out from the divers’ circle. A zodiac boat approached the whale
shark with a load of snorkelers, who then jumped in the water to swim beside the shark.
Fig. 4. Mean of divers recorded for each site.
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The shark then turned to the snorkelers with the mouth slightly open, causing the snor-
kelers to swim back quickly. As the whale shark approached, a second zodiac boat approa-
ched the shark and the animal then found itself caught between the two boats. The whale shark
descended once again, then rose again just beneath the zodiac, forcing the small boat to move
quickly away. Finally the shark descended once again, this time to return to the surface far
from the boats.
When pelagic thresher sharks are encountered in the blue, they swim slowly in the same
direction. However, when threshers are encountered near reefs, they tend to swim around
given spots, like a Gorgonian coral zone. When a thresher is approached by divers, it swims
straight away to the open ocean or parallel to the reef. If a thresher feels threatened or cornered,
it will perform a threat behavior with its mouth open to show its teeth. This is followed by
the lowering of the shark’s pectoral fins and the slight hunching of its back.
Silvertip sharks came up suddenly from the blue and swam in close proximity of divers
for about a minute, showing a relaxed behavior and then disappearing.
Grey reef sharks tend to show a more relaxed behavior. Most of the times when they
came into contact with divers, however, they became frightened and quickly swam away.
This is especially true for small specimens measuring less than 2 m. The bigger specimens
were mostly observed sitting still in strong currents.
Silky sharks have been seen coming from the open ocean to circle around a boat. At other
times, they have been seen with oceanic whitetip sharks. However, silky sharks tend to avoid
divers.
Fig. 5. The first author, Ahmed M. Shawky, swims with an oceanic whitetip shark Carcharhinus longimanus
(Poey, 1861), on October 22, 2008, in Elphinstone Reef. Photo by Mohamed Helmy.
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Oceanic whitetip sharks, at Elphinstone Reef were observed most often at the surface, near
boats parking at the South end of the reef. The oceanics have also been seen congregating
outside of the boat where the kitchen and toilets were located. Oceanic whitetip sharks seemed
to be used to the presence of divers (fig. 5), but were frightened by divers bubbles. Occasion-
ally, a diver tried to touch an oceanic whitetip shark as it passed by. The shark quickly swam
away from the offending diver for a few meters before slowing down. Some oceanic whitetip
sharks were observed keeping a vertical position while divers were finishing their safety stop
just before leaving the water to get back to an inflatable boat. Sometimes an oceanic whitetip
bit a diver’s fin or ruined a SMB (surface marker buoy). Some divers had to push an ocean-
ic whitetip on its nose to keep it at a distance. This caused the shark to change its direction
but only to soon return, appearing more nervous. At Daedalus Reef, oceanic whitetip sharks
were observed closely investigating people SCUBA diving at 25 meters by swimming straight
down from the surface to the divers near the reef. When divers tried to keep the oceanic
whitetips at bay, the sharks showed no fear towards the divers. This behavior was also report-
ed by dive tour guides at different Southern sites like Satayh.
Whitetip reef sharks were recorded mostly at coral gardens swimming over the reef. The
whitetip reef sharks were also seen resting over the sandy bottom within a reef garden or under
a coral head. When divers approached, the startled sharks swam quickly away in a wide circle
to deeper water, coming back near the same place only after the divers left the area.
Scalloped hammerheads were mostly recorded in current swept, deeper waters, far from
the reef. Firstly one or two hammerheads came near the reef facing the divers, then they
disappeared for 2-3 minutes before reappearing again with many other sharks, providing that
there was no noise or the divers left the area. However, if a diver used a signal device such
as a dive shaker, the shark went into deeper water at Daedalus Reef, or moved far from
Elphinstone Reef if the hammerhead was located there. At Brother Island, scalloped hammer-
heads were sometimes recorded at a 15 m depth near the reef. If the divers made no attempt
to touch the sharks, the sharks swam in a relaxed fashion around the divers for 15 minutes
or more. But when divers disturbed the hammerhead by producing noise or swimming sudden-
ly up to the shark, the hammerhead swam in a wide circle before continuing on in its usual
way after it left the divers far behind.
The sharks that showed less fear towards divers were oceanic whitetip sharks. These
animals approached the divers very closely during five encounters. In one case at Daedalus
Reef, on June 4, 2008, two oceanic whitetip sharks became aggressive to divers, gaping their
jaws in front of them and making circles around them. In one case at Elphinstone Reef on
August 20, 2008, three oceanic whitetip sharks became aggressive to snorkelers at the surface.
In another case on September 17, 2008, at Daedalus Reef, three oceanic whitetip sharks
became aggressive to divers and made circles around them, and a shark swam down and then
up going directly to the divers, catching the fins of one of them. During all other 107 encoun-
ters with sharks in this study, no aggressive behavior was observed.
The fearsome reputation of sharks is exaggerated: the human attack rate is very low,
usually the attack ends after the initial contact, and the shark does not eat or kill the victim
(DEMADDALENA, 2008). Of the eight shark species observed during this study, six are
among those usually considered dangerous or potentially dangerous, and the most abun-
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dant in the area is also the most dangerous of them, the oceanic whitetip shark. On safari
trips some seamen use food attached to a fishing line in order to attract sharks close to the
boat so to allow their guests to take photos of them, and at night cooks often throw food
remains in order to keep sharks around the boats all night long. In this case, the sharks can
become nervous and may be more inclined to attack humans, as already happened in 2008
when a guest swimming south of Daedalus Reef was attacked by an oceanic whitetip shark
that bit her leg after a seaman gave food to the sharks. Luckily, the victim was quickly picked
out of the water by the seaman and survived. Another attack occurred just a few months
ago at Elphinstone Reef, when a tourist diving with an oceanic whitetip shark tried to touch
the head of the animal, and it bit his leg. Luckily, even in this case, the victim survived.
One of the oceanic whitetip sharks encountered during this study had a hook with line in
its mouth. The fishermen use lines that are fixed vertically by weight and end with a balloon
at the surface. The fishermen fix this line at night and the sharks are easily attracted to it. When
the shark take the bait, it tries to escape by swimming deeper, but the balloon at the surface
prevents the shark’s escape. So, the shark keeps on trying until it dies, and the fishermen catch
it at early morning when no one can see them. Sharks have also been reported being killed
by collision with boat propellers, as happened to a 236 cm TL male shortfin mako Isurus oxyrin-
chus found dead on the coast in Ras Hankorab on May 1, 2008, after being hit on the dorsal
surface of its head by a boat propeller (Mohamed H. Besar, pers. comm. 2009).
DISCUSSION
The species recorded in the area during our study are the same encountered by the first
author during 170 dives in the 2005-2006 period. Therefore, their presence in the area is
clearly constant in time and they can be considered as usual inhabitants of these waters.
Humans create different kinds of interferences with shark behavior, through sound of
boat propellers, zodiac (inflatable boat) movements, bubbles produced by divers, divers
directly interacting with sharks such as when they follow the animals, sound signals among
diver buddies, waste products from diving boats (especially the Safari boats, that throw a
large amount of food remains into the sea at the end of the day), and fishing activities of
fishermen.
The oceanic whitetip sharks are easily attracted to the diving boats due to the waste
products of these boats. Other sharks, like scalloped hammerheads, especially at Daedalus
Reef, are scared by sounds. Park rangers have to act as dive guides to the divers, by asking
the guests to not use sound signals under water. Therefore the park rangers need to be in the
water first, before any other divers. Other common species like grey reef sharks, are easily
scared by the bubbles produced by the divers when they are abundant. Most sharks turn and
change direction when they meet a diver. This avoidance behavior was observed especially
in pelagic threshers, scalloped hammerheads and grey reef sharks. It has been noticed that,
once scalloped hammerhead sharks have been seen by divers, at Elphinstone Reef they go
into the blue far from the reef and come back after 3-5 minutes, but at Daedalus Reef the schools
of hammerheads stay together and dive deep rather than go far from the reef.
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The frequency of specimens per site is higher at Daedalus Reef, then followed by Small
Brother Is., Elphinstone Reef, and Big Brother Is. The frequency of encounters per site is higher
in Small Brother Is., followed by Daedalus Reef, Big Brother Is., and Elphinstone Reef. We
need to point out that the frequency of encounters at Elphinstone Reef is considerably lower
than in the other study areas. We suggest that the reason for this lowest frequency of encoun-
ters at Elphinstone Reef is due to the fact that this is the only unprotected area. Both the
mean of divers and the mean of boats recorded for each dive are higher at Elphinstone Reef
than at the other study sites. The highest peak in human presence was recorded at Elphin-
stone Reef. We believe that the massive human presence at this particular site is negatively
affecting the presence of sharks.
Comparing the situation of Elphinstone Reef with the one we observed at Daedalus Reef,
we note another relevant aspect. Daedalus Reef is well known for the presence of scalloped
hammerhead sharks. While boats are parked at the south of Daedalus Reef, hammerheads tend
to stay at the north, far from the disturbance caused by human presence. The situation is
different at Elphinstone Reef: the high number of boats is widely distributed over the entire
area, making it impossible for the sharks to avoid human presence.
We also note that one of the very rare cases in which sharks showed an aggressive behav-
ior against humans was observed in Elphinstone Reef, when there were present 13 boats
(9 boats and 4 speed boats) and 204 divers, a considerably higher number than the mean
recorded both in general and at this particular site. We infer that a massive human pres-
ence may negatively affect the behavior of sharks, especially of oceanic whitetip sharks
(the most dangerous species among those that have been recorded during our study), there-
fore increasing the probability of attacks on humans, an event exceptionally rare under
normal circumstances. The attack that occurred a few months ago at Elphinstone Reef
shows the importance for the people frequenting the diving sites to adopt an adequate
behavior in the presence of sharks. They should avoid touching sharks, especially those
belonging to dangerous species such as oceanic whitetip sharks.
In the end, taking into account all the considerations expressed above, we suggest that the
number of divers and boats frequenting Elphinstone Reef should urgently be regulated by appro-
priate rules. Also, a mode of conduct for those frequenting this area needs to be established.
It is therefore necessary that Elphinstone Reef be declared a protected area.
CONCLUSIONS
We strongly hope that this work will have a direct specific environmental benefit on
the shark populations inhabiting the Red Sea. The study sites of this work are already
protected areas, with the exception of Elphinstone Reef. The management plan for Elphins-
tone Reef will now be presented to the Egyptian Environmental Affairs Agency (EEAA),
of which the project curator and first author is an employee, as an Environmental Resear-
cher or Park Ranger, in order to allow the Red Sea National Park authorities to declare
Marsa Alam (Elphinstone Reef) a marine park, as has already been done for the other
study sites.
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References
BONFIL R., ABDALLAH M., 2004. Field identification guide
to the sharks and rays of the Red Sea and Gulf of
Aden. FAO Species Identification Guide for Fishery
Purposes. FA O , Rome, 71 pp.
COMPAGNO L.J.V., 1984. FAO Species Catalogue. Vol.
4. Sharks of the World. An annotated and illustrated
catalogue of sharks species known to date. Parts 1 and
2. FAO Fisheries Synopsis, 125: 1-655.
COMPAGNO L.J.V., 2001. Sharks of the World. Volume
2. FAO Species Catalogue for Fishery Purposes, No.
1 Vol. 2, 269 pp.
DEMADDALENA A., 2008. Sharks - The perfect preda-
tors. Jacana Media, Houghton, 198 pp.
LAST P.R., STEVENS J.D., 2009. Sharks and rays of
Australia. CSIRO, Australia, 656 pp.
RANDALL J.E., 1986. Sharks of Arabia. IMMEL Publish-
ing, London, 148 pp.
Indirizzo degli autori:
Ahmed M. Shawky - Egyptian Environmental Affairs
Agency (EEAA), Red Sea Protectorates, Marsa Alam
84721, Egypt; Ahmedshawky_7@hotmail.com
Alessandro De Maddalena - Solent Court 12,
Runciman Drive 136, Simon’s Town 7975,
South Africa; alessandrodemaddalena@gmail.com
(author for correspondence)
ACKNOWLEDGMENTS
Very special thanks to all the people who offered their help in preparing this work: Prof.
Mustafa Fouda – the Director Manager of Nature Conservation Sector (NCS) Egyptian Envi-
ronmental Affairs Agency (EEAA) – for his approval of this project; Dr Mahmoud Hanafy
– the scientific consultant for the Red Sea Governer and Red Sea Protectorates – for his
advice and support; Mr Yasser Saied – Manager of Red Sea Protectorates – for his encour-
agement and support; and to Mohamed H. Besar, Esam El Dein Mahran, Hany Forrera,
Ahmed Gamal, Ursula Halbeisen, Hamouda A. Shaaban, Rafael Morales, Kathryn Ann
Oldham, Margret Schaefer, Mohamed Helmy. Particular thanks to the Project AWARE Foun-
dation (Europe) of the PADI. Special thanks to John C. Bruner and Greg Amptman who kind-
ly edited the English text of this work. Many thanks also to Prof. Paolo Galli without who
the authors would have never started the collaboration for preparying the project. Particular
thanks from Alessandro De Maddalena go to his wife Alessandra and his son Antonio.
62
1092 06_9217_Shawky_DeMaddalena.qxp:StoriaNaturale64 5-12-2013 16:51 Pagina 62
... The few studies that have been carried out provide evidence of extirpation, or nearly so, over parts of these species' ranges (Dennis et al., 2005;Stallings, 2009;Ward-Paige et al., 2010;Luiz & Edwards, 2011;Ruppert et al., 2013). Carcharhinus albimarginatus is especially understudied, probably because its preference for deeper waters on outer forereefs prevents easy monitoring (Stevens, 1984;Friedlander et al., 2012;Espinoza et al., 2014) and so far it has typically only been analysed in taxonomically aggregated shark counts Goetze & Fullwood, 2013;Shawky & De Maddalena, 2013;Table SI, Supporting Information). ...
... Although some changes in behaviour can occur as sharks interact with diving operations (González-Pérez & Cubero-Pardo, 2010;Cubero-Pardo et al., 2011;Fitzpatrick et al., 2011b), this eco-tourism should have minimal effect on their populations (Maljković & Côté, 2011;Vianna et al., 2014). Sharks have been found to avoid areas of high human use, but this pattern is probably more reflective of fishing pressure and may be abated by the establishment of shark sanctuaries that incorporate conservation-minded diving practices (Garla et al., 2006;Stallings, 2009;Ward-Paige et al., 2010;Shawky & De Maddalena, 2013). ...
Article
Sharks are increasingly being recognized as important members of coral-reef communities, but their overall conservation status remains uncertain. Nine of the 29 reef-shark species are designated as data deficient in the IUCN Red List, and three-fourths of reef sharks had unknown population trends at the time of their assessment. Fortunately, reef-shark research is on the rise. This new body of research demonstrates reef sharks' high site restriction, fidelity and residency on coral reefs, their broad trophic roles connecting reef communities and their high population genetic structure, all information that should be useful for their management and conservation. Importantly, recent studies on the abundance and population trends of the three classic carcharhinid reef sharks (grey reef shark Carcharhinus amblyrhynchos, blacktip reef shark Carcharhinus melanopterus and whitetip reef shark Triaenodon obesus) may contribute to reassessments identifying them as more vulnerable than currently realized. Because over half of the research effort has focused on only these three reef sharks and the nurse shark Ginglymostoma cirratum in only a few locales, there remain large taxonomic and geographic gaps in reef-shark knowledge. As such, a large portion of reef-shark biodiversity remains uncharacterized despite needs for targeted research identified in their red list assessments. A research agenda for the future should integrate abundance, life history, trophic ecology, genetics, habitat use and movement studies, and expand the breadth of such research to understudied species and localities, in order to better understand the conservation requirements of these species and to motivate effective conservation solutions.
Article
Understanding why sharks bite humans is essential for developing strategies to prevent these incidents. Here, we use bite wound characteristics and eye witness descriptions of shark behavior to determine the likely motivation for several bites perpetrated by an oceanic whitetip (OWT) shark Carcharhinus longimanus on an adult female snorkeler off Moorea island (French Polynesia) in October 2019. The victim was snorkeling with others in pelagic waters as part of an organized whale‐watching tour when the shark—without any warning behavior—bit her at least three times resulting in severe injuries with substantial loss of soft tissue from the chest and both forearms. The victim survived these injuries thanks to rapid and effective first aid provided by her companions. The sudden, unprovoked and repeated bites with substantial tissue removal are consistent with predatory behavior although the dominance hypothesis cannot be fully ruled out. This would be the first case of a predatory shark bite ever documented in French Polynesia in over 70 years of data collection. Given the routine association of OWT sharks with cetaceans, in‐water whale watching activities should adopt appropriate risk management strategies in regions hosting this species of shark.
Sharks of the World. An annotated and illustrated catalogue of sharks species known to date. Parts 1 and 2. FAO Fisheries Synopsis
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COMPAGNO L.J.V., 1984. FAO Species Catalogue. Vol. 4. Sharks of the World. An annotated and illustrated catalogue of sharks species known to date. Parts 1 and 2. FAO Fisheries Synopsis, 125: 1-655.
Sharks -The perfect predators
  • Maddalena A De
DE MADDALENA A., 2008. Sharks -The perfect predators. Jacana Media, Houghton, 198 pp.
Red Sea Protectorates, Marsa Alam 84721, Egypt; Ahmedshawky_7@hotmail.com Alessandro De Maddalena-Solent Court 12, Runciman Drive 136, Simon's Town 7975
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Ahmed M. Shawky-Egyptian Environmental Affairs Agency (EEAA), Red Sea Protectorates, Marsa Alam 84721, Egypt; Ahmedshawky_7@hotmail.com Alessandro De Maddalena-Solent Court 12, Runciman Drive 136, Simon's Town 7975, South Africa; alessandrodemaddalena@gmail.com (author for correspondence)
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BONFIL R., ABDALLAH M., 2004. Field identification guide to the sharks and rays of the Red Sea and Gulf of Aden. FAO Species Identification Guide for Fishery Purposes. FAO, Rome, 71 pp.
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Red Sea Protectorates, Marsa Alam 84721, Egypt; Ahmedshawky_7@hotmail.com Alessandro De Maddalena -Solent Court 12
  • M Ahmed
  • Shawky -Egyptian
Ahmed M. Shawky -Egyptian Environmental Affairs Agency (EEAA), Red Sea Protectorates, Marsa Alam 84721, Egypt; Ahmedshawky_7@hotmail.com Alessandro De Maddalena -Solent Court 12, Runciman Drive 136, Simon's Town 7975, South Africa; alessandrodemaddalena@gmail.com (author for correspondence)
Particular thanks to the Project AWARE Foundation (Europe) of the PADI. Special thanks to John C. Bruner and Greg Amptman who kindly edited the English text of this work. Many thanks also to Prof
  • Mohamed H Besar
  • Esam El Dein Mahran
  • Hany Forrera
  • Ahmed Gamal
  • Ursula Halbeisen
  • A Hamouda
  • Rafael Shaaban
  • Kathryn Ann Morales
  • Margret Oldham
  • Mohamed Schaefer
  • Helmy
Mr Yasser Saied -Manager of Red Sea Protectorates -for his encouragement and support; and to Mohamed H. Besar, Esam El Dein Mahran, Hany Forrera, Ahmed Gamal, Ursula Halbeisen, Hamouda A. Shaaban, Rafael Morales, Kathryn Ann Oldham, Margret Schaefer, Mohamed Helmy. Particular thanks to the Project AWARE Foundation (Europe) of the PADI. Special thanks to John C. Bruner and Greg Amptman who kindly edited the English text of this work. Many thanks also to Prof. Paolo Galli without who the authors would have never started the collaboration for preparying the project. Particular thanks from Alessandro De Maddalena go to his wife Alessandra and his son Antonio.