Environmental Engineering Reference
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(at least) Côte d'Ivoire east to western Nigeria (Van
Waerebeek et al.
2001
,
2009
; Van Waerebeek
2003
). Further
south, the species occurs also off Gabon and the Republic of
Congo (Harmer
1928
; Rosenbaum et al.
2004
). Until the
present survey, no substantiated records of humpback
whales existed for Cameroon. Two calves captured inci-
dentally by artisanal fishers were landed and butchered for
food. Several other unidentified whales may also have been
humpback whales. The presence of calves suggests Camer-
oon waters may also be part of the calving ground in the
northern Gulf of Guinea. Freshly stranded or by-caught
whales are flensed and consumed mostly at the community
level. Reports from fishers, who (confusingly) call hump-
back whales ''cachalots'', suggest that their seasonality
coincides with those known from other coastal nations in the
northern Gulf of Guinea (Van Waerebeek et al.
2001
,
2009
).
While this will require testing, presumably the same or a
closely
of Delphinidae, both dead due to fisheries interactions: a
long-snouted common dolphin Delphinus capensis and a
common bottlenose dolphin Tursiops truncatus. Interviews
repeatedly suggested the occurrence of at least one species
of spotted dolphin (Stenella attenuata or Stenella frontalis).
On two occasions (one across the border in Equatorial
Guinea), a chunk of a freshly butchered dolphin had called
the attention of interlocutors due to its spotted skin. Both
spotted dolphin species have been documented from
by-catches in Ghana (Van Waerebeek et al.
2007
; Debrah
et al.
2010
) and are likely to occur also in Cameroon. A
striped dolphin was observed stranded on a beach, the body
has been severed by the time it was photographed but col-
ouration pattern positive identifies it as a striped (Stenella
coeruleoalba), a new species record for both Cameroon and
the Gulf of Guinea (Perrin and Van Waerebeek 2007 in
Ayissi et al.
2011a
,
b
). No striped dolphins have been found
during extensive dolphin by-catch monitoring in Ghana
(Ofori Danson et al.
2003
; Van Waerebeek et al.
2009
;
Debrah et al.
2010
). Weir (
2009
) and Weir et al. (
2011
) did
not sight S. coeruleoalba in the Gulf of Guinea, whereas it
was fairly frequent offshore Angola.
A larger dolphin locally known as ''iowa'' may be
identifiable with T. truncatus or O. orca. It is said to exhibit
an assertive, fearless behaviour towards people, vessels and
fishing gear. Francophone fishermen in Cameroon typically
refer to humpback whales as ''cachalots'', an obvious
source of confusion as the true ''cachalot'' (= sperm whale)
also appears to be a frequent visitor of Cameroonian waters.
Several fishermen independently mentioned a ''Dauphin
blanc'' (white dolphin), possibly identifiable with a com-
mon dolphin (Delphinus sp.). ''Dauphin blanc'' seen to be
distinguished
related
Southern
Hemisphere
humpback
whale
population is involved.
(3) Sperm whales
An entangled sperm whale Physeter macrocephalus was
stranded at Bakingili (N0404
0
17
00
, E0902
0
27
00
), Southwest
Region, in May 2005. It was flensed in situ and served as
food for many people from Limbe and Idenau. A second,
very large animal was stranded near Kribi in 2009; the
weathered skull of a third sperm whale, which was stranded
in 1990, was examined at Mpollongue.
(4) Other marine mammalian species
Over a distance of 30.52 km and 784 min duration,
beach combing effort was implemented on foot. Flotsam at
the high waterline was searched but no cetacean skeletal
specimens were found. However, after interviews with
fishermen, at times, we were shown miscellaneous cetacean
bones (primarily vertebrae and ribs) which were docu-
mented photographically. Cameroonians often utilize whale
bones, especially vertebrae, as ornaments at home. Enqui-
ries resulted in cetacean bones of some 10 specimens.
Single whale vertebrae, out of context, are difficult to
identify to species because many morphological features
overlap among species.
A fisherman who collected teeth from a small whale,
referred to as ''cachalot'', provided the teeth for study. The
teeth's pronounced curvedness and their relatively small
size (height 49.70-57.80 mm; max breadth 15.05-
23.95 mm; max thickness 13.30-16.30 mm) were initially
assumed to be from a juvenile P. macrocephalus. The pulp
cavities were filled to about half tooth length. However, the
shape, small size and lack of osteodentine (common in
sperm whale, see Boschma
1938
) would also concur with a
killer whale Orcinus orca. A detailed morphological com-
parison with reference specimens is awaited. Earlier field-
work yielded photographic evidence for two further species
from
dolphins
with
darker
flank
patterns,
presumably bottlenose and humpback dolphins.
Waterbirds
Sixty-one (61) waterbird species represented in 17 families
have so far been recorded. The families Ardeidae, Scol-
opacidae, Charadriidae and Alcedinidae have the highest
with 12, 10, 8 and 7 species, respectively. The migratory
status is also presented
Of the 61 species, 22 (36.1 %) appeared to be resident
while 21 (34.4 %) and 16 (29.5 %) were seasonal and
occasional visitors, respectively. Of particular significance
is the high abundance of African Skimmers, Grey Prantic-
oles, Open-billed Storks and Common Green Shank with
monthly numbers of up to 811, 583, 336 and 189, respec-
tively, close to Glazebrook et al. (
1998
) counts of 833, 318,
414 and 77, respectively, for River Sanaga during their
coastal waterbirds survey of Cameroon Coast in February
1998. According to them, River Sanaga holds nationally
significant
numbers
of
Grey
Pranticole
and
African
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