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Inshore occurrence of southern right
whales (Eubalaena australis) at Subantarctic
Marion Island
M. Postma*, M. Wege, M.N. Bester, D.S. van der Merwe & P.J.N. de Bruyn
Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria,
Private Bag X20, Hatfield, 0028 South Africa
Received 10 January 2011. Accepted 8 March 2011
Opportunistic shore-based sightings of southern right
whales Eubalaena australis for Marion Island
(46°54’S, 37°45’E) were documented at five different
times between 1974 and 2009. Whales were sighted
between May and September and exclusively on the
eastern lee side of the Island. Notwithstanding
some observer biases over this time frame, the species
appears to be an infrequent visitor to the inshore
marine environment of Marion Island.
Key words:Eubalaena australis, Marion Island, shore-
based sightings; Southern right whale, vagrants.
Owing to their thick blubber, southern right
whales are reluctant to venture into the tropics,
and are usually found between 20° and 64° south
(Fig. 1) (Best 2007). The fact that they float when
dead, have a superior oil and whalebone yield,
fidelity to congregate near calving grounds and
their lack of speed must all have contributed to
their exploitation by commercial whaling (Best
2007). Although protected in 1935, illegal whaling
endureduntil1971(Tormosovetal.1998).Between
1971 and 1998 the calving population off the coast
of South Africa increased with 7.1% per year,
similar to rates of increase recorded for populations
offthe coast of Argentina and Australia(Best2007).
In winter months southern right whales migrate
to more temperate coastal waters off the southern
continents, where females give birth and nurse
their newborn in these sheltered areas (Best 2007).
At other times of the year whales move south from
the calving grounds to the foraging grounds where
temperatures are cooler and overall biological
productivity is higher (Perrin et al. 2002). In the
south Indian sector of the Southern Ocean, right
whales are mainly seen between 30°S and 40°S
from October to December, between 40°S and 50°S
around the Crozet Islands (CI) mainly from Febru-
ary to March, and in the area between 50°S and
60° S from December to April (Best 2007). Here
we report on five photographically confirmed
inshore sightings of the species at Marion Island
(46°54’S, 37°45’E) over a period of 35 years.
The Prince Edward Archipelago consists of
two small islands, Marion Island (MI) and Prince
Edward Island which are located in the southern
Indian Ocean (Pakhomov & Froneman 1999).
Oceanographically, MI is situated directly in the
path of the easterly-flowing Antarctic Circumpo-
lar Current (ACC), between the Subantarctic Front
(SAF) and Antarctic Polar Front (APF) (Fig. 2)
(Lutjeharms 1985). Currently, the nearest southern
right whale calving grounds to MI are ~1950 km
distant,offtheWesternCapeProvince,SouthAfrica.
Sightings of southern right whales at MI were
primarily recorded by elephant seal researchers
during regular visits (every 7–10 days) on foot to
all the beaches on the northeastern, eastern and
southern side of the island (Fig. 3). Round island
resightswereconductedonce a month. The research
effort which is associated with the southern
elephant seal (Mirounga leonina) mark-resighting
programme has been repeated whole year round
since commencement in 1983 (see de Bruyn et al.
2008 for details). As part of this highly structured
pinniped monitoring programme, seal research-
ers were also required to record opportunistic
sightings of killer whales (Orcinus orca). Additionally,
dedicated land-based killer whale observation
sessions were performed year-round since 2008,
during which trained observers remained at set
observation points (Fig. 3) and visually searched
for killer whales for pre-determined (3-hour or
10-hour) lengths of time (Reisinger et al. 2011a).
Following annexation of MI in 1947/1948 by
SouthAfrica(Cooper&Headland1991),theearliest
reported sightings of southern right whales are
those of an adult individual of unknown sex seen
in September 1974 (Condy & Burger 1975). The
animal was noted over a period of several days
while swimming in circles approximately five
metres off the eastern coast about 1 km north of the
*Author for correspondence.
E-mail: mpostma@zoology.up.ac.za
African Zoology 46(1): 188–193 (April 2011)
meteorological station (Fig. 3). Recent examination
of photographs taken over that period confirms
that two different individuals were involved (P.
Best, pers. comm. 2010). During August 2006 an
adult of unknown sex was sighted and photo-
graphed in Storm Petrel Bay on the north coast of
the Island (Fig. 3). This animal meandered in large
circlesandrandompatternswithinthisonebayfor
Short communications 189
Fig.1.Distr ibution map for southern right whales. (Reprinted with permission from Cambridge University Press, taken
from Best, 2007.)
Fig. 2. The position of Prince Edward Islands in relation to South Africa and the CI.Major frontal systems including the
Subtropical Convergence (STC), Subantarctic Front (SAF) and Antarctic Polar Front (APF) are shown. (Reprinted
with permission from Pakhomov & Froneman 1999.)
at least an hour from initial observation. It ap-
peared to be feeding, as the animal’s mouth could
be seen to open near the surface on several occa-
sions. A juvenile animal (8–10 m) of unknown sex
was sighted in August 2008 in poor visibility (due
to snow squalls) at Ship’s Cove on the northeast-
ern coast (Fig. 3). The animal was being harassed
by three killer whales. The observed attack contin-
190 African Zoology Vol. 46, No. 1, April 2011
Fig. 3. Map of Marion Island, Southern Indian Ocean, showing the locations (Mixed Pickle Cove, Cape Davis, Goney
Beach, Pinnacles Beach, Rockhopper Bay, Kildalkey Bay and Watertunnel Beach) where dedicated killer whale
observations were made. Offshore dots indicate southern right whale sightings. (Adapted from Reisinger
et al.
2011a.). Arrows indicate elephant seal researchers’search area every 7–10 days (since 1983). Offshore dots indicate
southern right whale sightings.
Fig. 4. Photograph of a juvenile southern right whale sighted in 2009 immediately north of the meteorological station
at Marion Island.
ued for 20 min, with killer whales circling the
whale within a distance of 10 m after which they
moved off. For the next 2 hours the whale re-
mained in the cove swimming in circles showing
signs of fatigue with irregular breathing, although
this subsided as time passed. The next morning
the whale was nowhere to be seen. Most recently
(in May 2009) a juvenile of the species was re-
corded in approximately the same location as the
sightings in 1974. From photographs and the size
of the head it could be classified as a very young
animal (Fig. 4) (I. Peters, pers. comm. 2010). The
latter was sighted alone; this could be as a result of
the decreased visibility due to heavy mist on that
particular day or the absence of other individuals.
Interestingly, all animals appeared to behave simi-
larly by swimming in circles or random meanders
between about 5 m and 50 m off the coast.
The low sighting frequency of southern right
whales around the eastern and northern coasts of
MI is unlikely to be markedly biased by observer
presence given that an almost uninterrupted field
presence of primarily pinniped biologists com-
menced in 1973 (Condy 1978; de Bruyn et al. 2008).
These field workers routinely documented the
presence of any unusual or rarely seen marine
mammal species (e.g. Bester et al. 2006; de Bruyn
et al. 2007; Reisinger et al. 2009) and additionally
paid particular attention to the inshore waters for
opportunistic killer whale (Orcinus orca) sightings
(e.g. Keith et al. 2001; Tosh et al. 2008). Transients
such as leopard seals (Hydrurga leptonyx) and
humpback whales (Megaptera novaeangliae) are
occasionally sighted when they visit the inshore
area at MI (Bester et al. 2006; Ryan & Bester 2008).
Leopard seals may be benefiting from locally
abundant food resources such as penguins (Bester
etal.2006)andhumpbackwhalesmayberestingin
the calm waters. This poses but two hypotheses to
the question of why right whales visit MI:
1) Some individuals, from the pelagic concentra-
tion of southern right whales around the CI (Best
2007), are possibly swimming diagonally across
the ACC (Fig. 2) to their calving grounds off the
coast of southern Africa, on their way stopping at
MI. MI’s coastline consists mainly of cliffs on the
western side with sheltered pebble beaches on
the eastern side (Condy 1978). Right whales were
recorded only on the eastern side of MI; this could
imply that whales rest in the calmer leeward side,
although observer effort on the western side of
MI, albeit relatively constant, is lower than on the
eastern side. Sightings were in May 2009, August
2006, 2008 and September 1974 at the beginning
and at the end of winter, respectively. This timing
suggests that these animals are en route to more
temperate grounds in low latitudes at the beginning
of the austral winter and from these grounds to
higher latitudes once winter has passed. It is there-
fore tempting to speculate that MI may only be an
occasional en route stopover on an annual migra-
tion to the South African coastline (present study),
although no links between the latter and the for-
aging area around the CI have been demonstrated
(Best 2007). MI is also not in a direct line between
the known foraging area (at CI) and the east coast
of southern Africa (Fig. 1), a possible destination
(Best 2007).
2) On the other hand, the waters around MI are
frequently patrolled by killer whales (Orcinus
orca), particularly the inshore areas (Reisinger et al.
2011a). Elsewhere killer whales have been observed
attacking right whales. Such encounters are rarely
sighted, but could be fatal for young or unaccom-
panied animals, as southern right whales usually
group together for protection against killer whales
(Best et al. 2010). Killer whale sightings occur
throughout the year but peak between Septem-
ber–December and April–May (Reisinger et al.
2011a). The September to December peak coincides
with breeding of southern elephant seals (Mirounga
leonina) and penguin species (Condy et al. 1978;
Reisinger et al. 2011a, b). This potential threat to
right whales by killer whales may explain why few
sightings of right whales have been realized,
despite intensive observer presence for the past
four decades.
The APF and Subtropical Convergence are con-
sidered as popular right whale feeding grounds;
more specifically the area around CI at 45°S and
Kerguelen Islands (‘Desolation’) at 49°S (Town-
send1935).Rightwhalesmustseekoutandexploit
extremely dense patches of prey in order to feed
efficiently (Kenney et al. 1986) where they con-
sume copepods (71.4%), euphausiids (24.3%) and
crustaceans (4.3%) (Tormosov et al. 1997; Mate et al.
2010). MI lies west of these usual foraging regions
(Fig. 5) and as such may be oceanographically
unfavourable as a feeding ground. According to
ship logbooks from 1785 to 1913 no sightings of
southern right whales were made in the vicinity of
the Prince Edward Islands (Townsend 1935)
(Fig. 5). These five records between 1974 and 2009
are the only reported sightings of the species
inshore at MI. Sightings of southern right whales
at MI are infrequent and the species can be classi-
Short communications 191
192 African Zoology Vol. 46, No. 1, April 2011
fied as a rare vagrant at the Island. MI’s position in
the Southern Ocean potentially makes it a sheltered
resting stop for a few individuals en route from the
known Crozet Islands feeding grounds (February
and March) to the winter calving grounds in
southern Africa. Alternatively, passing individuals
may be exploiting unpredictable food patches
opportunistically.
We thank the South African Department of Environ-
mental Affairs for providing logistical support within the
South African National Antarctic Programme and the
Department of Science and Technology (administered
through the National Research Foundation) for funding
the marine mammal monitoring programme at Marion
Island. We are also extremely grateful to the field assis-
tants who recorded sightings when we were not in the
field.
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