Editing Pacific loon (section)

=== Territoriality ===
[[Socially monogamous mammals|Socially monogamous]] Pacific loons have been found to have high territory retention rates (0.92) indicating that the loons are able to successfully defend their nesting lake from other loon pairs or individuals who may be trying to move in. Furthermore, males have a greater success at territory retention than females, but no evidence suggests that this difference is attributed to size but is rather due to fighting ability or familiarity with territory.<ref name=":1">{{Cite journal|last1=Uher-Koch|first1=Brian D|last2=Wright|first2=Kenneth G|last3=Schmutz|first3=Joel A|date=2019-02-01|title=The influence of chick production on territory retention in Arctic-breeding Pacific and Yellow-billed loons|url=https://academic.oup.com/condor/article/doi/10.1093/condor/duy021/5381709|journal=The Condor|language=en|volume=121|issue=1|pages=duy021|doi=10.1093/condor/duy021|s2cid=198160438|issn=0010-5422}}</ref>

Pacific loons prospecting for a new lake frequently visited lakes that were already occupied, this along with high retention rates of lakes indicates that the loon population in Northern [[Alaska]] may be saturated. The Pacific loon has also been known to be very [[Aggression|aggressive]], engaging in [[Interspecific|interspecific killing]] of both hatch year and after hatch year individuals who intentionally or accidentally approach the loon's nesting area.<ref name=":2">{{Cite journal|last1=Kirkham|first1=Ian R.|last2=Johnson|first2=Stephen R.|date=1988|title=Interspecific Aggression in Loons (Agresión Interespecífica en Somormujos (Gavia spp.))|url=https://www.jstor.org/stable/4513284|journal=Journal of Field Ornithology|volume=59|issue=1|pages=3–6|jstor=4513284|issn=0273-8570}}</ref>

A pair of Pacific loons will defend young as a parental unit in which one parent protects the nest or [[Fledge|fledglings]] while the other parent aggressively attacks the perceived threat. If the threat is another animal on the water, the attacking loon will extend its head and neck in an aggressive manner and dive under the threat in an attempt to stab it with its beak as it resurfaces.<ref name=":3">{{Cite journal|last=Robertson|first=Gregory J.|date=1993|title=Interspecific Killing in the Pacific Loon|url=https://www.jstor.org/stable/4163337|journal=The Wilson Bulletin|volume=105|issue=3|pages=534–535|jstor=4163337|issn=0043-5643}}</ref><ref name=":2" /> Pacific loons are so aggressive, they have even been observed displaying threatening body language towards passing [[airplane]]s in Alaska.<ref name=":3" />