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Table 2 Table of comparative cognition between the ethological observations made in situ and the Atalaia fishermen's knowledge regarding S. guianensis behaviour, including their respective fidelity levels

From: Behaviour of Sotalia guianensis(van Bénéden, 1864) (Cetacea, Delphinidae) and ethnoecological knowledge of artisanal fishermen from Canavieiras, Bahia, Brazil

Behaviour In situ observation Fisherman’s citation Level of fidelity
Seasonality S. guianensis groups were observed in each of the 12 months of observation “We see them throughout the year” (26) 1
Movement and tidal cycle Individuals entered more frequently at high tide and exited more frequently at low tide, following the movement of the tide “It depends on the tide. But they enter more frequently at high tide and exit more frequently at low tide. They are smart fish" (19) 0.73
Gregarious A total of 70 groups and 252 individuals were recorded of which only two were lone animals “They only travel in groups. It's unusual to see them alone" (26) 1
  The size of groups ranged from two to seven individuals “There are groups of two, four, six, eight" (26) 1
Feeding Feeding events were the behaviours most frequent recorded “They come here to fish” (26) 1
  Circling and chasing were most frequently observed “They create a circle. They chase the rake stardrum (Stellifer rastrifer)from underneath and all the fish jump to get away” (26) 1
  An adult beats its fin on mangrove roots and three other individuals then execute shallow dives “They beat their tails on the mangrove branches to scare the fish” (10) 0.38
  * “They go to the shallows, right up to the water's edge, to get the beached fish. Then they go back into the water” (3) *
Reproductive Positive correlation between number of infants and size of group “We always see some little ones with them. One, two, it depends on the size of the group” (14) 0.53
  Infants were not seen in November “They have infants with them all year” (17) 0.65
  Significant difference in the number of infants over the 12 months of observation "There is a time of year when there are more, but I'm not sure when" (13) 0.50
  No reproductive events were recorded “I've never seen them mating around here" (26) 1
On the surface Leaping, slapping and spyhopping were recorded “Criss-crossing each other. Lone jumps. Jumps and rotates, performing a "pirouette" (18) "Shows its beak, slaps its wing and tail" (19) 0.69
0.73
Play Locomotor, social and play with object were recorded “Jumps, crosses, slaps wing, somersaults, jumps, jumps onto mother, back flips, raises its head out of the water then sinks back, throws rake stardrum (Stellifer rastrifer)into the area. All kinds of play." (26) 1
  1. Number of citations is in brackets.
  2. *Behaviour not observed in situ and with no equivalence for the S. guianensis species in the literature.