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CHAPTER 23 New Caledonia (South Pacifi c) as a Potential Tropical Wintering Ground for the White Shark, Carcharodon carcharias

Authors:
  • IRD (Institut de Recherche pour le Développement)

Abstract and Figures

Several occurrences of White Sharks in tropical waters have been reported, but in the context of gaps in the knowledge of the ecology of that top predator, they appear as unusual and unexpected destinations. The New Caledonian exclusive economic zone covers 1,400,000 km 2 , with sea-surface temperatures oscillating between 20 and 21°C in winter and 28 and 32°C in summer. We have vali-dated fi fty-two sightings of White Sharks between 1943 and 2010, mainly based on professional fi shing bycatches and observations at sea. We obtained information on season in thirty-nine cases, shark size in forty-seven cases, and gender in twelve cases. To this, we added information for six different animals that were tagged with pop-up archival tags in New Zealand in April 2005 (two sharks) and March 2009 (four sharks), before releasing their tags in New Caledonian waters a few months later. Fifty-two percent of the animals were spotted in winter (July to September), 26% in spring (October to December), 23% in summer (January to March), and none in fall (April to June), which corresponds with the best season for tagging them in New Zealand. Thirty-two percent of the sharks were shorter than 3.8 m total length (TL), 45% between 3.8 and 4.4 m TL, 15% between 4.5 CONTENTS
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341
CHAPTER 23
New Caledonia (South Paci c) as a Potential
Tropical Wintering Ground for the White
Shark, Carcharodon carcharias
Eric Clua and Bernard Séret
ABSTRACT
Several occurrences of White Sharks in tropical waters have been reported, but in the context of
gaps in the knowledge of the ecology of that top predator, they appear as unusual and unexpected
destinations. The New Caledonian exclusive economic zone covers 1,400,000 km2, with sea-surface
temperatures oscillating between 20 and 21°C in winter and 28 and 32°C in summer. We have vali-
dated  fty-two sightings of White Sharks between 1943 and 2010, mainly based on professional
shing bycatches and observations at sea. We obtained information on season in thirty-nine cases,
shark size in forty-seven cases, and gender in twelve cases. To this, we added information for six
different animals that were tagged with pop-up archival tags in New Zealand in April 2005 (two
sharks) and March 2009 (four sharks), before releasing their tags in New Caledonian waters a few
months later. Fifty-two percent of the animals were spotted in winter (July to September), 26% in
spring (October to December), 23% in summer (January to March), and none in fall (April to June),
which corresponds with the best season for tagging them in New Zealand. Thirty-two percent of the
sharks were shorter than 3.8 m total length (TL), 45% between 3.8 and 4.4 m TL, 15% between 4.5
CONTENTS
Abstract .......................................................................................................................................... 341
Introduction .................................................................................................................................... 342
Material and Methods .................................................................................................................... 343
Results ............................................................................................................................................344
Number and Location of the Sightings .....................................................................................344
Size and Gender of the Animals ............................................................................................... 344
Seasonality and Local Mobility ................................................................................................ 345
Discussion ......................................................................................................................................346
Conclusion ......................................................................................................................................348
Acknowledgments .......................................................................................................................... 349
References ...................................................................................................................................... 350
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342 GLOBAL PERSPECTIVES ON THE BIOLOGY AND LIFE HISTORY OF THE GREAT WHITE SHARK
and 5 m TL, and 8% above 5 m TL. The smallest animal was 2.6 m TL and the largest was 5.5 m
TL. The sex ratio was unbalanced, with twelve males and six females. As in other tropical islands,
the peak presence of White Sharks in winter coincided with that of humpback whales that come
to mate and calve in New Caledonian waters in winter before leaving in October. The extended
presence of White Sharks until the end of summer could be linked to other sources of food such as
spawning aggregations of reef  shes and deep-sea snappers, in addition to other usual prey. New
Caledonian waters appear to be a wintering ground for South Paci c White Sharks, and the study
of their ecology should be addressed at a regional level for providing critical information aimed at
ensuring their sustainable management in this part of the world.
INTRODUCTION
In spite of the critical role that it plays in marine ecosystems as a top predator (Baum et al.,
2003), the distribution and ecology of the White Shark (Carcharodon carcharias) are still poorly
understood (Bruce, 2006). The largest of the carnivorous sharks is considered to be mainly distrib-
uted in temperate waters (Last and Stevens, 1994; Compagno et al., 1997; Compagno, 2001), but
with a wide thermal tolerance that allows it, like other lamnids, to reach boreal latitudes (Weng
etal., 2005). Satellite tracking technology has enabled several authors to show that White Sharks
can travel thousands of kilometers (Bon l et al., 2005) and on occasion penetrate tropical waters
and swim around coral reefs (Figure 23.1). Boustany et al. (2002) and Domeier and Nasby-Lucas
(2008), for example, showed that several large White Sharks regularly migrate from the west coast
of North America to Hawaii, where an adult individual stayed up to 122 d, and another was able to
cop e with sur face temperatures up to 27.2°C (Weng et al., 20 07a). An af nity for warm water seems
to be mor e pronou nced for yo ung anima ls, wh ich live in cold waters dow n to 10°C bu t se em to prefe r
higher temperatures up to 23°C (Dewar et al., 20 04; Weng et a l., 200 7b). Young-of-the -year ani mals
from the west coast of North America use tropical environments for their development, migrating
South from the Southern California Bight (at 34°S) toward Baja California, Mexico (29°S) (Weng
etal., 2007b). All of the information scienti cally collected so far about White Sharks spending
time in warm waters was obtained through studies that followed the animals from their temper-
ate, and presumed usual, habitats toward unexpected tropical destinations. Information gathered
AQ1
AQ2
Figure 23.1 Male White Shark (4.0 m TL) observed September 2007 over a coral reef in the Dumbea Pass,
southern lagoon of New Caledonia. This observation was made by a group of  ve scuba divers at
an averagedepth of 25 m. (Courtesy of Luc Bourdil.)
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343NEW CALEDONIA AS A POTENTIAL TROPICAL WINTERING GROUND FOR THE WHITE SHARK
from the perspective of potentially important tropical habitats, however, contributes toward a better
understanding of the ecology of White Sharks.
New Caledonia is an archipelago composed of a main island (16,800 km2) surrounded by smaller
islands of tens to hundreds of km2, at the center of an exclusive economic zone (EEZ) ranging from
15 to 25°S and 155 to 17E. This represents an area of 1,400,000 km2 of tropical waters with a
temperature oscillating between 20 and 22°C in winter and 28 and 32°C in summer (Figure23.2).
The main island is 3,000 km east of Queensland, Australia, and around 2,500 km northeast of the
North Island of New Zealand. The  rst of cial identi cation of a White Shark in the tropical waters
of New Caledonia was recorded in 1943 (Anonymous, 2005), and since then, despite its presence
being well known in New Caledonian waters (Fourmanoir and Laboute, 1976; Séret, 1994), no
speci c investigation has been conducted to better understand the ecology of this top predator in
this area. Furthermore, the role that this part of the south Paci c Ocean may play at a regional level
in the life cycle and ecology of this species remains unknown. In this paper, we analyzed all of the
available data on White Shark occurrences in New Caledonia to test the hypothesis that they use
New Caledonian waters as a long-duration wintering ground.
MATERIAL AND METHODS
Observations of White Sharks in New Caledonian waters were compiled through several
channels, including interviews with recreational and professional  shermen, spear  shermen, and
scuba divers and other scientists and naturalists working at sea. Records provided by professional
AQ3
20°0’S
25°0’S
0 150 300 Km
155°0’E 160°0’E 165°0’E 170°0’E
15°0’S
Chesterfield
Reefs Bellona
Northern
Lagoon
Shelf
Entrecasteaux
Reefs
Southern
Lagoon
New Caledonia
Economic exclusive zone
Main
Island
Noumea
Sarcelle Pass
Grand
Coude
lle des Pins
500
500
100
167°0’S
168°0’S
22°0’S
23°0’S
Antigonia
Reef
Figure 23.2 Location of con rmed White Shark records within the New Caledonian EEZ. Black icons
represent shark records Table 23.1, and white icons represent the pop-up locations of tags
from sharksinTable 23.2.
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344 GLOBAL PERSPECTIVES ON THE BIOLOGY AND LIFE HISTORY OF THE GREAT WHITE SHARK
shermen are mainly based on bycatch of White Sharks, which are hooked and tangled on longlines.
Other records are mainly based on sightings of the animals either on the surface or underwater by
scuba and free divers. When a photo was provided, it allowed con rmation of the identi cation
and sometimes an assessment of the size and gender. Given the perceived status of this animal as a
threat to humans, the occurrence of a White Shark is usually highlighted by the local newspaper Les
Nouvelles Calédoniennes, which was a useful source of information through original copies stored
at the Bernheim Library in Noumea. Even more sparse is information found in naturalist publica-
tions such as  sh identi cation books (Fourmanoir and Laboute, 1976; Laboute and Grandperrin,
2000). A nonexhaustive list of White Shark occurrences in New Caledonia can be found in Clua
and Séret (2010), which deals with a fatal shark attack attributed to this species at Lifou Island
in September 2007, as well as another fatal accident with a young surfer along the west coast of
the main island in March 2009 (E. Clua, unpublished data). In addition, some scienti c data were
recently provided from studies conducted in New Zealand since 2005, aiming to provide informa-
tion about the movements of White Sharks through pop-up archival tagging. These studies showed
that six different White Sharks tagged in New Zealand released their tags in New Caledonian
waters, two in 2005 (Bon l et al., 2010) and four in 2009 (Duffy et al., Chapter 21, this volume).
These studies provided accurate data on the size and gender of the animals.
RESULTS
Number and Location of the Sightings
We c omp i led  fty-three White Shark records from the New Caledonian EEZ (Figure 23.2) dat-
ing between 1943 and 2010, four of which were identi ed as resightings of the same animal (see
below). The remaining forty-nine occurrences comprised professional  shing bycatch, sightings
by recreational boats, scienti c assessments (including forensics), and observations of scavenging
events on large marine mammals (Table 23.1). Eighty percent of the records were concentrated
around the southern part of the mainland. This area (enlarged in Figure 23.2) encompasses the
Southern-West lagoon, the Iles des Pins and the surrounding passage, and sea mounts to the south.
Size and Gender of the Animals
An assessment of shark size was possible in forty-four cases (Figure 23.3). Sharks smaller than
3.8 m TL were assumed to be immature because this is the maturity threshold for males (Pratt,
1996). Sharks above 4.5 m TL were potentially mature females because this is the threshold for
female maturity (Francis, 1996). About a third (32%) were immature, but only two animals were
Table 23.1 Observations of White Shark (Carcharodon carcharias) in New Caledonian
waters, 194 3–2010
Years Fishing Bycatch Recreational
Scienti c and
Forensics
Scavenging
Event Total
1943–1970 5 0 0 2 7
1971–1990 4 0 0 0 4
1991–2000 12 2 0 2 16
2001–2010 5 10 5 2 22
To t a l 2 6 12 5 6 4 9
The table shows observations of White Shark (Carcharodon carcharias) in New Caledonian waters,
1943–2010, classi ed by time period and source. All of the observations were veri ed by a shark
researcher and had accurate locations.
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345NEW CALEDONIA AS A POTENTIAL TROPICAL WINTERING GROUND FOR THE WHITE SHARK
shorter than 3 m TL. The smallest animal was 2.6 m TL, and the most reliable record of the largest
one was around 5.5 m TL. This last observation was made in February 1992 by comparison with the
length of the hull of the boat along which the shark passed several times (P. Simoni, personal com-
munication). Most of the animals (45%) had a total length between 3.8 and 4.4 m, a few (15%) were
between 4.5 and 5 m, and only 8% were longer than 5 m TL. The gender of the animals was avail-
able in eighteen records, combining the visual observations (Table 23.1) and the tagging programs
(Table 23.2). There was an unbalanced sex ratio of twelve males to six females.
Seasonality and Local Mobility
The month of White Shark occurrences in New Caledonian waters was recorded for thirty-
nine cases. Around a half (52%) were observed in winter (July to September), and a quarter were
observed either in spring (October to December) (26%) or in summer (January to March) (23%)
(Figure 23.4). There was not a single White Shark record in New Caledonian waters during fall
(April to June).
There is little information about resightings of animals that could permit reliable descriptions of
speci c movements within the New Caledonian EEZ. In two cases, probably the same animal was
m
>5 m TL
4.5 m to 5 m TL
3.8 m to 4.4 m TL
<3.8 m TL
0 5 10 15 20 25 30
reshold for female maturity
reshold for male maturity
35 40 45 50
%
Figure 23.3 Number of sharks per length intervals (n = 47). The length of 3.8 m TL was chosen as threshold
for mature males (Pratt, 1996). The interval 3.8– 4.4 m TL represents the animals that are mature
as male but still immature as female. The length of 4.5 m TL was chosen as threshold for mature
females (Francis, 1996). The length of 5 m was chosen as a threshold for ver y large animals.
Table 23.2 Location in the New Caledonian EEZ and Date of Release of Pop-up Archival Tags
Tagging
Date
Tagging
Location
Pop-up
Date
Pop-up
Location Area Gender
Size
(m) Reference
4/8/2005 Chatham
Islands
10/5/2005 21°11S, 169°38EEast of Mare
Island
M 3.4 Bon l et al.
(2010)
4/9/2005 9/5/2005 22°45S, 167°09ESouthern Shelf
of Isle of Pine
F 4.0
3/24/2009 Stewart
Islands
12/20/2009 21°33S, 159°16EBellona Shelf F 4.0 Duffy et al.
(Chapter 21,
this volume)
3/27/2009 10/8/2009 17°44S, 162°45EEntrecasteaux
Archipelago
F 3.3
3/30/2009 8/12/2009 22°12S, 167°12ENorth of Yate
Pass
M 2.9
3/31/2009 8/24/2009 21°30S, 159°14EBellona Shelf M 4.0
The table shows the locations in the New Caledonian EEZ and dates of release of pop-up archival tags set on six
White Sharks in New Zealand in April 2005 (Chatham Islands) and March 2009 (Stewart Islands).
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346 GLOBAL PERSPECTIVES ON THE BIOLOGY AND LIFE HISTORY OF THE GREAT WHITE SHARK
spotted twice on the same or following day. On August 23, 2008, a 4 m TL female was spotted by a
helicopter pilot in the southern lagoon (B. Civet, personal communication) and few hours later in a
neighboring pass (less than  ve nautical miles away) in the barrier reef by a group of spear  sher-
men (A. Leconte, personal communication). On March 6, 2009, the White Shark responsible for
the fatal attack on a young surfer at 11 a.m., was spotted 10 min. before by researchers conducting
an aerial survey of dugongs, Dugong dugong, several miles south of the sur ng spot (C. Garrigue,
personal communication). Another record some 10 nautical miles from the attack was made the day
after by an ultra light Aircraft pilot (S. Timboni, personal communication), unfortunately without
any accurate assessment of the size that could con rm that it was the same shark.
DISCUSSION
The record of forty-nine occurrences in more than 50 yrs. cannot be considered an accurate
assessment of the density of White Sharks in New Caledonia. In fact there were only seven reliable
records in almost 30 yrs. between 1943 and 1970 (Table 23.1). This lack of information is due to
the low interest given to such observations, exacerbated by the poor capability for recognizing this
speci c shark. The information became more reliable by the 1970s with the development of local
longline  sheries. An average of four boats per year reported bycatches of White Shark until the
late 1990s, when this type of shing was replaced by deep-sea snapper lining with electric reels.
Large animals break the snapper lines when they predate a hooked  sh, reducing the captures of
White Sharks. These bycatch records, however, represent most of the twenty-six records for the
three decades between 1970 and 2000, showing an average of almost one sighting of White Sharks
per year, based on a similar annual  shing effort. The 10-yr. period between 2000 and 2010 showed
twenty-two occurrences, that is, an average of 2.2 sightings per year (Table 23.1). This higher  gure
25
Summer Fall Winter Spring
20
15
10
5
0
January
October
September
August
July
June
May
April
March
February
November
December
30
%
Figure 23.4 Seasonal occurrences (n = 39) of White Sharks in New Caledonia with regard to the season: 52%
in winter (July to September), 23% in spring (October to December), 25% in summer (January to
March), andnone in fall (April to June).
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347NEW CALEDONIA AS A POTENTIAL TROPICAL WINTERING GROUND FOR THE WHITE SHARK
can be explained by the increasing number of people, mainly recreational users (including divers),
traveling long distances thanks to GPS technology, increasing the probability of shark encounters.
Despite the increased number of potential observers, the chance of seeing a White Shark among
reef ecosystems remains very low. White Sharks spend less than 8% of their time in shallow, warm
waters of 0–5 m, whereas this surface time is around 22% in cooler waters during other periods of
the year (Weng et al., 2007a). Francis et al. (Chapter 22, this volume, and personal communication)
showed that for tagged White Sharks in tropical waters (n = 9), the mean time in the 0 –1-m depth
range was 19.7%, but the amount varied considerably among sharks. The appearance of White
Sharks at the surface is signi cantly increased in the presence of a whale carcass on which they
regularly feed (Cliff et al., 1996; Long and Jones, 1996; Curtis et al., 2006; Dicken, 2008). Such a
situation occurred twice in New Caledonia (1997 and 2006) and produced sightings of two White
Sharks each time (Table 23.1).
The unbalanced location of sightings between the southwest area of New Caledonia (80%) and
the rest of the EEZ (20%) is explained by the proximity of the capital Noumea, which contains 60%
(around 120,000 people) of the overall population and the highest density of recreational sea users
in New Caledon ia. Noume a harb or is also t he base for most of the pr ofessiona l shing boats that, for
economic reasons, use the closest  shing area between 100- and 600-m depth, off the Grand Coude,
south to the Ile des Pins, and the Antigonia seamount (Figure 23.2). However, this area might also
constitute important habitat for the White Shark given its geomorphology: a wide passage with
strong currents and local upwellings separates the main island from the Ile des Pins, and the lagoon
offers an open barrier reef, several islets, and intermediate reefs in deep waters (up to 70 m). This
“intermediate” area between the reef and open sea is the preferred mating and nursing ground for
humpback whales, Megaptera novaeangliae, in New Caledonia. Humpback whales utilize the shel-
ter and easy access to the open ocean offered by this area. Of the remaining 20% of sightings of
White Sharks outside the southern area, half were within a radius of 150 km on the western coast
of the southern province of New Caledonia, still in the most inhabited area of the territory. The
human-density factor is a driving factor for White Shark records; this assumption is supported by
the fact that only two pop-up tags were recorded in the southern area (around the Ile des Pins), with
a more widespread distribution of the other four animals within the New Caledonian EEZ, in the
north (around Entrecasteaux Archipelago), the west (around the Bellona Shelf), and the northeast
(off Mare Island) (Figure 23.2). This suggests that the density of White Sharks in the caledonian
EEZ might be higher than shown by the average yearly records.
Given the demonstrated philopatry of female White Sharks (Pardini, 2001), the unbalanced sex
ratio in favor of males (2:1), and the apparently low presence in New Caledonian waters of poten-
tially mature females over 4.5 m TL (Francis 1996), this region does not appear to play a reproduc-
tive role. Considering that the sharks were elsewhere before arriving in New Caledonia, such as New
Zealand as determined by the tagging programs, their arrival coincides with the calving period of
humpback whales. White Shark presence in New Caledonian waters peaks in July and August and
then decreases until November when most of the cetaceans have left the area (Garrigue et al., 2002).
This pattern is consistent with similar observations in the Hawaiian Islands (November to May;
Taylor, 1985; Boustany et al., 2002; Weng et al., 2007a; Domeier and Nasby-Lucas, 2008) or for
Western Australia and at similar latitudes to New Caledonia in subtropical Queensland, Australia
(Paterson and Paterson, 1989; Bruce et al., 2006). White Sharks may follow large cetaceans, expect-
ing feeding opportunities based on vulnerable newborn animals and males exhausted after mating
ghts or just scavenging on the huge placentas of humpback whales (Bon l et al., 2010).
However, some White Sharks remain in New Caledonia until the end of summer, long after the
humpback whales have left the area in October, requiring a complementary hypothesis to explain
their extended presence. It has been suggested that White Sharks are able to spend extended peri-
ods in a given area when food resources are available but then move rapidly in search of other
prey sources when it disappears (Long et al., 1996; Bruce et al., 2006). In spite of the departure
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348 GLOBAL PERSPECTIVES ON THE BIOLOGY AND LIFE HISTORY OF THE GREAT WHITE SHARK
of humpback whales from New Caledonian waters before summer, White Sharks remain pres-
ent in densities consistent with spring (Figure 23.4). Werry et al. (Chapter 19, this volume) noted
a similar trend with the catch records of White Sharks (1993–2010) in the Queensland Shark
Control Program. This trend might be explained by another source of food, starting to increase by
November and lasting until March. A potential food source is the spawning aggregations of reef
shes. White Sharks forage on schools of  shes elsewhere, such as on sparids, Pagrus auratus, in
southern Australia (Malcolm et al., 2001). An observation of a White Shark feeding on orange spot
groupers, Epinephelus coioides, hooked by a handline  sher on a spawning aggregation in Prony
Bay, southern lagoon of New Caledonia, in November 2008 (L. Pascal, personal communication)
supports this hypothesis. As bycatch on longlines set at over 300-m depth revealed in the 1980s and
1990s, White Sharks also feed on deep-sea snappers, in particular queen and ruby snappers, Etelis
spp. In the South Paci c, spawning aggregations for these two species start in November and last
until May (Mof tt, 1993). In New Caledonia, above-average catch rates of these deep-sea snappers
are experienced by  shermen from November until February through March (P. Boblin, personal
communication) and also for crimson snappers, Pristipomoides spp., which peak in January (A.
Desurmont, unpublished data). These aggregations may therefore constitute a reliable source of
food for White Sharks before they start migrating away from New Caledonian waters in the fall.
Other potential prey of Great White Sharks are marine mammals such as pygmy sperm whales,
Kogia breviceps (Long, 1991), sea turtles (Fergusson et al., 2000), and large  shes such as tunas,
which all occur year-round in New Caledonian waters. The presence of these preys could help to
explain the extended residence of White Sharks.
In the southwest Paci c, a seasonal pattern of migration between temperate and tropical waters
has been shown through several tagging programs by Bruce et al. (2006). Australian White Sharks
occupy the Great Australian Bight during the southern spring and summer, make northward
movements during autumn and winter through New South Wales (NSW) into tropical waters of
Queensland, and return to the southern region by early summer. This seasonal pattern of latitudinal
migration between temperate and tropical waters is supported by the capture of White Sharks by
shark control programs in NSW and Queensland and even attacks on humans attributed to White
Sharks that peak in late summer/autumn in NSW and in spring in Queensland (West, 1996). Bruce
et al. (2006) also showed, through the example of a single shark that returned to Neptune Island in
Southern Australia 286 d after it was tagged there, that White Sharks undertaking such extensive
movements remain part of a southern Australian population and may show patterns of site  delity
similar to that reported for White Sharks in Californian and South African waters (Klimley, 1985;
Long et al., 1996; Bon l et al., 2005). For such movements, these sharks spend the majority of time
near the Australian coast, but Bruce et al. (2006) also reported a single pelagic movement from
Australia to New Zealand, showing connectivity between these two areas. That same connectivity
is supported by the example of a 4.0 m TL male that was tagged in Stewart Island in March 2009
and had a pop-up release in the Bellona Shelf, New Caledonia, in August 2009 (Table 23.2), after
passing through the Coral Sea off the Queensland coast (Duffy et al., Chapter 21, this volume).
Results from the tagging program from New Zealand support the hypothesis of an interconnected
population of White Sharks in the southwest Paci c, encompassing southern and western Australia,
New Zealand, and New Caledonia and eastward to Fiji and Tonga (Bon l et al., 2010; Duffy et al.,
Chapter 21, this volume).
CONCLUSION
Evidence for interconnectivity among Australian, New Zealand, and New Caledonian White
Sharks is sparse but convincing. In the absence of a speci c monitoring program, White Sharks are
dif cult to observe in tropical waters. The occurrences in New Caledonia indicate that their density
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349NEW CALEDONIA AS A POTENTIAL TROPICAL WINTERING GROUND FOR THE WHITE SHARK
is quite low but that their residency time is signi cant (up to 9 months per year), with a strong peak
in winter. Therefore, New Caledonian waters appear to play an important role as a tropical win-
ter residency ground for South Paci c White Sharks, including young animals. These consistent
and long-lasting residencies result in Great White Sharks mixing with other large predators such
as tiger sharks, Galeocerdo cuvier, particularly during scavenging events on cetacean carcasses
(Dudley et al., 2000). The presence of two White Sharks, a 3.5 m TL male and a 4.0 m TL female,
around the carcass of a dwarf sperm whale, Kogia breviceps, carcass stranded on the fringing reef
of Ugo Islet in September 2006 scared away several tiger sharks that were already in the vicinity
(E.Clua, unpublished data). In December 1998, two White Sharks were observed in the La Sarcelle
pass (between the mainland and the Ile des Pins), scavenging on the drifting carcass of a sperm
whale, Physeter macrodon, surrounded by tens of tiger sharks. No particular hostility was wit-
nessed between these two top predators, and they were sometimes feeding on the carcass together
(Figure 23.5) (B. Civet, personal communication).
The regular and extended presence of White Sharks, including young animals, in New
Caledonian waters suggests there is potential for studying their interactions with large cetaceans
and other top predators. The development of regional programs for tagging White Sharks in the
New Caledonian EEZ appears to be a critical step toward a better understanding of the ecology of
this endangered species in this part of the world. These data will be paramount for supporting an
effective management plan at a regional scale and the implementation of speci c regulations for
protecting this top pelagic predator while utilizing tropical waters in New Caledonia.
ACKNOWLEDGMENTS
We are grateful to all the people from New Caledonia who shared their data on White Sharks,
especially Pierre Larue. We also thank Bruno Civet and Luc Bourdil for allowing us to publish their
photos of White Sharks. The information provided by our colleagues from New Zealand, Clinton
Duffy and Malcolm Francis, was critical, and we warmly thank them for their con dence. Finally,
we gratefully acknowledge comments by our Australian colleagues, Jonathan Werry from Grif th
University and Clive Wilkinson from the Reef Rainforest Research Center in Townsville, on an
Figure 23.5 White Shark and tiger shark scavenging together on a sperm-whale carcass in the pass of La
Sarcelle, December 1997. Both sharks were around 4.0 m TL. (Courtesy of Bruno Civet.)
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350 GLOBAL PERSPECTIVES ON THE BIOLOGY AND LIFE HISTORY OF THE GREAT WHITE SHARK
earlier draft of this paper. This study bene tted from the  nancial support of the CRISP (Coral
Reef InitiativeS for the Paci c) Programme Coordinating Unit at the Secretariat of the Paci c
Community in Noumea, New Caledonia.
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... Our observations were consistent with past studies as white sharks and tiger sharks were seen feeding with little overt inter or intraspecific aggression displayed. It is common to see multiple individuals of the same (Clua et al., 2013;Curtis et al., 2006;Dicken, 2008;Fallows et al., 2013) and different (Clua and S eret, 2012;Dudley et al., 2000;Lea et al., 2018) shark species scavenging the same carcass. Gallagher et al. (2018) even records tiger sharks and saltwater crocodiles (Crocodylus porosus) concurrently scavenging a humpback whale carcass north of Montgomery Reef, Australia. ...
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