Open AccessMagellanic Penguins Spheniscus magellanicus commuting through San Julian Bay; do current trends induce tidal tactics?
Author(s) -
Wilson R. P.,
Locca R.,
Alejandro Scolaro J.,
Laurenti Sonia,
Upton Jorge,
Gallelli Hector,
Frere Esteban,
Gandini Patricia
Publication year - 2001
Publication title -
journal of avian biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.022
H-Index - 76
eISSN - 1600-048X
pISSN - 0908-8857
DOI - 10.1034/j.1600-048x.2001.320113.x
Subject(s) - bay , current (fluid) , foraging , biology , tidal current , energetics , seasonal breeder , ecology , zoology , fishery , oceanography , geology
The behaviour of Magellanic Penguins Spheniscus magellanicus commuting between their foraging areas and breeding areas in San Julian Bay, Argentina was studied to examine whether tidal rip currents affected travelling patterns. Although there was no apparent relationship between departure and arrival patterns and the state of the tidal cycle, birds travelling against the current dived for longer periods and had shorter rests on the surface than birds travelling with the current. In addition, birds swimming against the current hugged the banks of tidal rivers much more closely than did birds swimming with the current, thus reducing the magnitude of the current against which they had to swim. In cases of extremely high current speeds, birds travelling upstream walked. Models regarding the energetics of movement indicate that the strategies adopted by Magellanic Penguins can result in substantial energy savings.