caa a22 4500 46578187X CHVBK 20180323111957.0 cr unu---uuuuu 170327e19900101xx s 000 0 eng 10.1007/BF00174025 doi (NATIONALLICENCE)springer-10.1007/BF00174025 Temeles Ethan Department of Zoology, University of Tennessee, 37996-0810, Knoxville, TN, USA aut Northern harriers on feeding territories respond more aggressively to neighbors than to floaters [Elektronische Daten] [Ethan Temeles] Summary: Territory owners often respond less aggressively towards intruding neighbors than towards intruding floaters, an observation termed "the dear enemy phenomenon.” Comparisons of territory owners' responses to intruding neighbors versus their responses to intruding floaters usually have been made for owners of multi-purpose and/or breeding territories. Here, I describe responses of female northern harriers Circus cyaneus (owners) on winter feeding territories towards three types of intruders (female neighbors, female floaters, and male floaters) and show that the dear enemy phenomenon does not occur. Owners' responses towards neighbors were more intense (mostly flights rather than calls) than responses towards female floaters, which in turn were more intense than responses towards male floaters. The greater intensity of owners' responses towards neighbors compared to owners' responses towards male and female floaters may be related to differences in the threat posed by each of the three intruder types in terms of fighting ability (RHP) and potential losses from intrusion. Hence, whether owners respond more aggressively towards neighbors or floaters, and whether the dear enemy phenomenon is observed, may depend upon the relative magnitude of threat presented by neighbors and floaters to owners in terms of fighting ability and potential losses from intrusion. Springer-Verlag, 1990 Behavioral Ecology and Sociobiology Springer-Verlag 26/1(1990-01-01), 57-63 0340-5443 26:1<57 1990 26 265 https://doi.org/10.1007/BF00174025 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00174025 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Temeles Ethan Department of Zoology, University of Tennessee, 37996-0810, Knoxville, TN, USA aut NATIONALLICENCE 773 0- Behavioral Ecology and Sociobiology Springer-Verlag 26/1(1990-01-01), 57-63 0340-5443 26:1<57 1990 26 265 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer