Phalarope - - - Pomarine Jaeger B B + Parasitic Jaeger B B + Long-tailed Jaeger B B B Great Skua - - ?
Phalarope - - Pomarine Jaeger + - Parasitic Jaeger - + Long-tailed Jaeger + B Great Skua - - Franklin's Gull - - Black-headed Gull - - Mew Gull - - Thayer's Gull + + Iceland Gull - - Glaucous Gull + + Great Black-backed Gull - - Black-legged
Phalarope - Pomarine Jaeger - Parasitic Jaeger - Long-tailed Jaeger B Great Skua - Franklin's Gull - Black-headed Gull - Mew Gull - Thayer's Gull + Iceland Gull - Glaucous Gull B Great Black-backed Gull - Black-legged
Phalarope + + Pomarine Jaeger + + Parasitic Jaeger B B Long-tailed Jaeger B B Great Skua - - Franklin's Gull - - Black-headed Gull + + Mew Gull + + Thayer's Gull B + Iceland Gull - - Glaucous Gull B B Great Black-backed Gull - - Black-legged
Parasitic Jaeger Stercorarius parasitus (French: Labbe parasite; Inuktitut: Isunngaq or Ishungak): Uncommon breeder.
Migrating Parasitic Jaegers, on the other hand, offer an excellent system in which to investigate the formation mechanisms and ecological determinants of foraging group size.
In early fall, the sandbar serves as a migratory stopover for Parasitic Jaegers, Common Terns, Black-legged Kittiwakes (Rissa tridactyla), and many shorebird species.
At the start of each block, I counted the abundance (number) of Parasitic Jaegers and of Common Terns (flying and not flying) within one observation perimeter (second-order-patch).
Outcome of kleptoparasitic interactions involving Parasitic Jaegers against Common Terns as a function of jaeger group size, at the Portneuf sandbar.
Results obtained in this study are comparable to those that I obtained when investigating the feeding behavior of migrating Parasitic Jaegers at the same site in 1991 and 1992 (Belisle and Giroux 1995), and are also consistent with general patterns found in studies of other mono- and interspecific seabird systems that make use of kleptoparasitism (Furness 1987a, b).