Lecture Topic: Territories
Territory: a defended area.
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territory vs.home range: home range is area within which a bird spends
most of its time, over a specified period
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resources provided by territories: mating opportunities (especially for
males); floaters, males without territories, may not mate. Food for adults,
young; protection against predators; sites...
Types of territories:
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Type A - all purpose breeding (breeding, feeding of adults; food for young.)
ex: many passerines, raptors, a variety of species
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Type B - nesting; some feeding of nestlings; adults feed elsewhere. ex:
red-winged blackbirds
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Type C - nest only. ex: many gulls, auks
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Type D - mating only. ex: lek species such as many grouse, manakins, etc.
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polyterritoriality: male holds more than one, non-consecutive territory.
ex: Pied Flycatcher (a European species in the thrush and relatives group)
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non-breeding territories: birds of either sex may hold territories in the
winter. May defend against individuals of either sex.
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non-territorial species: many species are not observed to defend areas.
Ex: many finches (Fringillidae)
Territorial defense:
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usually by males against conspecific males; displays, songs, fights...
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female defense of territories
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monogamous species: females may defend joint territory against females
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polygynous species: females may defend a smaller territory within the male
territory
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interspecific territoriality: rare
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may occur "by mistake" if species can not recognize each other
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may occur between competitors: red-winged blackbirds and yellow-headed
blackbirds where the species occur together