The Common Murre nests in densely packed colonies (known as "loomeries"), with up to twenty pairs occupying one square metre at peak season.[citation needed] Common Murres do not make nests and lay their eggs on bare rock ledges, under rocks, or the ground. They first breed at four to six years old and average lifespan is about 20 years.
Immature birds return to the natal colony, but from age 5 onwards ~25% of birds leave the colony, perhaps dispersing to other colonies.[20]
U. a. aalge colony, Gull Island, Witless Bay Ecological Reserve, Newfoundland and Labrador. Atlantic Puffins nest in burrows in the grassy area.
High densities mean that birds are close contact with neighbouring breeders.[21] Common Murres perform appeasement displays more often at high densities and more often than Razorbills.[21] Allopreening is common both between mates and between neighbours. Allopreening helps to reduce parasites, and it may also have important social functions.[22] Frequency of allopreening a neighbour correlates well with current breeding success.[22] Allopreening may function as a stress-reducer; ledges with low levels of allopreening show increased levels of fighting and reduced breeding success.[22]
The Common Murre nests in densely packed colonies (known as "loomeries"), with up to twenty pairs occupying one square metre at peak season.[citation needed] Common Murres do not make nests and lay their eggs on bare rock ledges, under rocks, or the ground. They first breed at four to six years old and average lifespan is about 20 years.
Immature birds return to the natal colony, but from age 5 onwards ~25% of birds leave the colony, perhaps dispersing to other colonies.[20]
U. a. aalge colony, Gull Island, Witless Bay Ecological Reserve, Newfoundland and Labrador. Atlantic Puffins nest in burrows in the grassy area.
High densities mean that birds are close contact with neighbouring breeders.[21] Common Murres perform appeasement displays more often at high densities and more often than Razorbills.[21] Allopreening is common both between mates and between neighbours. Allopreening helps to reduce parasites, and it may also have important social functions.[22] Frequency of allopreening a neighbour correlates well with current breeding success.[22] Allopreening may function as a stress-reducer; ledges with low levels of allopreening show increased levels of fighting and reduced breeding success.[22]
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