However, reasons for the construction of nest scrapes are poorly understood. Working on Pectoral Sandpipers, Jane Reid tested the hypothesis that using a lined scrape reduces the rate of clutch heat loss & investigated whether scrapes are effectively designed to minimize heat loss rates.
Pectoral Sandpipers therefore used lining materials appropriate to minimizing heat loss given their damp breeding environment.
Spacing of Bank Swallow tunnel entrances (Ghent 2001) -- Tunnel entrance distributions at six Bank Swallow sand-pit colonies showed consistently nonrandom, too-regular patterns, supporting the hypothesis that the distance between tunnel entrances is determined by territorial disputes at the tunnel mouths.
This indicates that the even the earliest birds built nests to protect their eggs and young (From: Chiappe 2009). Cornell Lab of Ornithology, Ithaca, NY; Retrieved from the Birds of North America Online: Scharf, W.
Orientation and microclimate of Horned Lark nests -- Across their range, Horned Larks typically construct nests adjacent to & north of objects such as a tuft of grass or a rock.
Each solid circle represents one entrance orientation. Cornell Lab of Ornithology, Ithaca, NY; Retrieved from the Birds of North America Online: Reneerkens, J., T.
The dashed line designates the mean entrance orientation angle of 345° for all nests (n = 10; Hartman and Oring 2003).
The dashed circle represents the outline of a nest.
Each individual curved black bar represents the vegetation around one nest.
The use of both an unlined scrape and of lining material reduced the rate at which a test object lost heat.