445
16.3 Recognizing Right Whales and Learning About Their
Lives
Individual recognition of animals in the wild is used since the first studies of ethology and ecology. The detailed investigation of activity patterns, associations and
social interactions, as well as movements and habitat use, requires the individual
identification of animals. Individual recognition also allow monitoring populations
over time. Some species exhibit individually specific natural markings that facilitate
identification in the field. For species that lack such distinctive markings, artificial
marks, or tags, can be attached if individual identifications are desired (Wells 2009).
Photographic identification of naturally marked animals or photo- identification, is a
powerful, non-intrusive technique to obtain several information in natural populations (Hammond 1990).
Cetaceans exhibit a variety of individually distinct natural characteristics. In general, the features as head, back, dorsal fin and tail, that appear above the water surface during the respiratory cycle are the most useful, for ease of viewing and
recording (Wells 2009). Variations occur in the skin color patterns, shape of dorsal
fins, spots and scars along the body (Hammond et al. 1990).
The first systematic studies of photo-identification of cetaceans began in the 70s,
after the discovery of the possibility of individually distinguish bottlenose dolphins
by their dorsal fins (Wursig and Wursig 1977), and right whales (Eubalaena spp)
from aerial photographs of the callosity patterns found on their heads Payne et al.
(1983).
The callosities are raised patches of roughened skin on the head of right whales,
colonized by thousands of cyamids (amphipod crustaceans: Cyamus spp) or “whale
lice”, whose light bodies clearly distinguish callosity tissue from intervening areas
of smooth black skin (Fig. 16.2) (Payne et al. 1983). Cyamids are ectoparasites,
which feed on the epidermal layer of whale skin and pass all live stages on cetaceans (Rowntree 1996). There are mostly three species of cyamids occurring on
southern right whales: (1) C. ovalis (white, living in great quantities on the callosities); (2) C. gracilis (light yellow, restricted on the callosities, found, in jumbled
masses); (3) C. erraticus (orange, found usually in isolated disc-shaped clusters on
the base of callosities, on smooth skin between callosities, in the axes of flippers, in
genital-anal grove and in wounds). In southern right whales the callosities are also
inhabited by barnacles (Best 1991; Kenney 2009).
Callosities on a right whale head have similar distribution to the hairs on human
face. They occur on the anterior and posterior margin of the blowholes, along the
rostrum, on the upper margin of the lower lip, on eyebrows, on the chin, and along
the mandible (Fig. 16.3) The number, shape and location of the calluses is unique to
each whale. A calf’s initial infestations arrive by vertical transmission from its
mother, and the pattern is established in the first months of calves’ life. There is a
succession of cyamids on calves callosities, which are first “infested” by orange
cyamids (C. erraticus), on the base of the callosities, on the sides of the head and the
axes of flippers. As the calf grows, orange cyamids are replaced by white and yellow
16 Conservation Advances for the Southern Right Whales in Brazil
16.3 Recognizing Right Whales and Learning About Their
Lives
Individual recognition of animals in the wild is used since the first studies of ethology and ecology. The detailed investigation of activity patterns, associations and
social interactions, as well as movements and habitat use, requires the individual
identification of animals. Individual recognition also allow monitoring populations
over time. Some species exhibit individually specific natural markings that facilitate
identification in the field. For species that lack such distinctive markings, artificial
marks, or tags, can be attached if individual identifications are desired (Wells 2009).
Photographic identification of naturally marked animals or photo- identification, is a
powerful, non-intrusive technique to obtain several information in natural populations (Hammond 1990).
Cetaceans exhibit a variety of individually distinct natural characteristics. In general, the features as head, back, dorsal fin and tail, that appear above the water surface during the respiratory cycle are the most useful, for ease of viewing and
recording (Wells 2009). Variations occur in the skin color patterns, shape of dorsal
fins, spots and scars along the body (Hammond et al. 1990).
The first systematic studies of photo-identification of cetaceans began in the 70s,
after the discovery of the possibility of individually distinguish bottlenose dolphins
by their dorsal fins (Wursig and Wursig 1977), and right whales (Eubalaena spp)
from aerial photographs of the callosity patterns found on their heads Payne et al.
(1983).
The callosities are raised patches of roughened skin on the head of right whales,
colonized by thousands of cyamids (amphipod crustaceans: Cyamus spp) or “whale
lice”, whose light bodies clearly distinguish callosity tissue from intervening areas
of smooth black skin (Fig. 16.2) (Payne et al. 1983). Cyamids are ectoparasites,
which feed on the epidermal layer of whale skin and pass all live stages on cetaceans (Rowntree 1996). There are mostly three species of cyamids occurring on
southern right whales: (1) C. ovalis (white, living in great quantities on the callosities); (2) C. gracilis (light yellow, restricted on the callosities, found, in jumbled
masses); (3) C. erraticus (orange, found usually in isolated disc-shaped clusters on
the base of callosities, on smooth skin between callosities, in the axes of flippers, in
genital-anal grove and in wounds). In southern right whales the callosities are also
inhabited by barnacles (Best 1991; Kenney 2009).
Callosities on a right whale head have similar distribution to the hairs on human
face. They occur on the anterior and posterior margin of the blowholes, along the
rostrum, on the upper margin of the lower lip, on eyebrows, on the chin, and along
the mandible (Fig. 16.3) The number, shape and location of the calluses is unique to
each whale. A calf’s initial infestations arrive by vertical transmission from its
mother, and the pattern is established in the first months of calves’ life. There is a
succession of cyamids on calves callosities, which are first “infested” by orange
cyamids (C. erraticus), on the base of the callosities, on the sides of the head and the
axes of flippers. As the calf grows, orange cyamids are replaced by white and yellow
16 Conservation Advances for the Southern Right Whales in Brazil