title: Unravelling feeding territoriality in the Little Blue Heron, Egretta caerulea, in Cananéia, Brazil.
abstract: Habitat use by the Little Blue Heron (Egretta caerulea) and discovery of feeding territoriality are discussed here. The results showed the existence of a territorial individual defending an area (2,564.46 +/- 943.56 m(2)) close to the mangrove, and non-territorial individuals (9.17 +/- 2.54) in the rest of a demarcated area (mean area for the non-territorial: 893.25 +/- 676.72). A weak positive correlation (r = 0.47, df = 46, p < 0.05) was found between the overlapping of territorial and non-territorial individuals (2.85 +/- 3.07 m(2)) and the mean overlapped area for territorial individuals (171.41 +/- 131.40 m(2)). Higher capture (1.52 +/- 1.14 x 1.00 +/- 1.37 catches/minutes) and success rates (0.45 +/- 0.31 x 0.21 +/- 0.27) and lower energy expenditure rates (45.21 +/- 14.96 x 51.22 +/- 14.37 steps/minutes; and 3.65 +/- 2.55 x 4.94 +/- 3.28 stabs/minutes) were observed for individuals foraging in areas close to the mangrove. The results suggest that the observed territorial behaviour is more related to a number of food parameters than to intruder pressure, and also that the observed territoriality might be related to defense of areas with higher prey availability.
authors.affiliation: Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil. manubioufpr@yahoo.com.br <manubioufpr@yahoo.com.br>
authors.forename: E
authors.initials: E
authors.lastname: Moralez-Silva
authors.forename: F J L
authors.initials: FJ
authors.lastname: Silva
authors.forename: E L A
authors.initials: EL
authors.lastname: Monteiro-Filho
mesh_terms: D000818:Animals; D001717:Birds / Q000145:classification / Q000502:physiology*; D001938:Brazil; D017753:Ecosystem; D005247:Feeding Behavior / Q000502:physiology*; D011235:Predatory Behavior / Q000502:physiology*; D013731:Territoriality