Cavity Depth, Not Experience, Determines Nest Height In Eastern Bluebirds

The major aim of this study was to examine the influence of the European Pine Marten (Martes martes) predation on the heights of nests of Blue Tits (Cyanistes caeruleus) and Great Tits (Parus major) in nestboxes of different security levels. To this end we performed a comparison of nest heights before and after introducing an anti-predator device to two size-types of wooden nestboxes set up in a deciduous forest. Blue Tit and Great Tit nest sizes were influenced by the application of plastic entrance tubes as anti-predator devices that elongated a distance between the entrance and the interior of the nestbox. Nests were taller in nestboxes equipped with anti-predator devices regardless of nestbox size. Nests located in smaller nestboxes were destroyed by Martens more frequently than nests built in bigger nest boxes. Most nest functions in cavity-nesting birds, such as filling the excessive cavity space, maintenance of proper humidity, thermal, light and sanitary conditions for eggs and nestlings, improve with nest sizes. Because, in contrast, the risk of nest predation by martens increases with nest size (height within the nestbox), the nest predation constitute a major factor that constrains cavity-nesting birds in constructing tall nests.

Section: Introductionmentioning

confidence: 99%

“…al., 1996Heeb et. al., , 2000Soler et al, 2007;Moreno et al, 2008;Mainwaring and Hartley, 2009;Deeming et al, 2012;Stanback et al, 2013).…”

Section: Introductionmentioning

confidence: 99%

Does the Threat of European Pine Marten (Martes Martes) Predation Influence the Height of Nests Built by Blue Tits (Cyanistes Caeruleus) and Great Tits (Parus Major)?

Kaliński

Wawrzyniak

Bańbura

et al. 2014

“…Another study of a resident population of Eastern Bluebirds breeding at a similar latitude to ours found no effect of a female's within-season breeding experience on nest height. 46 Some nest boxes were manipulated with inserts to have 5-cm shorter cavity depths before settlement; those breeders' first nests were shorter (had less material) on average than their second attempt nests when the full nest cavity height was restored. 46 These findings similarly suggest the bluebirds adjusted the amount of nest material according to cavity depth.…”

Section: Discussionmentioning

confidence: 99%

“…46 Some nest boxes were manipulated with inserts to have 5-cm shorter cavity depths before settlement; those breeders' first nests were shorter (had less material) on average than their second attempt nests when the full nest cavity height was restored. 46 These findings similarly suggest the bluebirds adjusted the amount of nest material according to cavity depth. First and second nests built in the same boxes were significantly positively correlated in height, supporting the female individuality component of variation that we also report in this study, and that has been reported in Blue Tits.…”

Section: Discussionmentioning

confidence: 99%

Natal philopatry is associated with smaller nest size in a cavity-nesting bird with consequences for nest box temperature

Reed

McRae

2022

Considerable within-population variation in nest size exists among cavity nesters. We sought to explain this by studying a multi-brooded population of Eastern Bluebirds (Sialia sialis) breeding in nest boxes. We examined seasonal change in nest weights and compared the weights of nests built by immigrant and resident females. We further investigated whether nest weight correlated with maternal condition or breeding success. Nest weight measured after broods fledged was correlated with nest height at the start of incubation. Breeders spent fewer days building and built successively smaller, lighter nests in later nesting attempts. Female bluebirds performed the majority of nest construction. Nests built by immigrant females were significantly larger on average than those built by female recruits hatched on site, and the seasonal decline in nest weight was more pronounced for natally philopatric females. For the first time, we present evidence that the weights of philopatric females’ first nests were significantly positively correlated with the weights of the nests they were raised in, suggesting an effect of natal memory. Contrary to expectation, neither maternal condition nor reproductive success (clutch size, hatching success, brood size, and fledging success) was related to nest weight. To investigate whether smaller nests provided a thermal advantage in summer nest attempts when afternoon box temperatures can exceed 41°C, we measured the temperature within nest boxes using programmable data loggers. Mean daily maximum box temperatures during incubation were significantly positively related to nest weight and significantly negatively related to the volume of free space above the nest. Increased air circulation above the nest likely contributed to cooling the boxes when ambient temperatures were high. Reducing nest size was therefore advantageous, especially in later nesting attempts when ambient temperatures were warmest. Seasonal decline in nest weights and differences between immigrant and natally philopatric females merits further investigation.

“…Other species are flexible when building nests. Stanback et al (2013) showed that Eastern Bluebirds (Sialia sialis) adjust the height of nests according to cavity depth, and Britt and Deeming (2011) demonstrated that Blue Tits (Cyanistes caeruleus) used less (non-scarce) nesting material as ambient air temperatures warmed leading up to nest construction. There has been less direct evidence, however, for birds modifying the microenvironment into which nests are placed (Howlett and Stutchbury, 1997;Leader and Yom-Tov, 1998).…”

Section: Discussionmentioning

confidence: 99%

Facultative Nest Modification by Rock Wrens (Salpinctes obsoletus)

Warning

Benedict

2016

Dynamic nest-construction behaviours suggest that nest structures can be facultatively adjusted in response to environmental conditions. This is particularly true when nest builders create environmental structures that are supplemental to the nest itself, because these structures can be adapted to nest site conditions. Rock Wrens ( Salpinctes obsoletus) mechanically alter their nest environments by amending rock-based cavities with stones, which are placed below their soft nest cups and often occlude cavity entrances, and extending out of nest cavities. We measured stones and cavity dimensions in 68 Rock Wren nests to quantify stone form and functional variability in stone use. Nests in our study contained stones with a consistent, flat shape, suggesting that Rock Wrens were selective when choosing stones for use around nests. We found significant positive correlations between the size of the nest cavity entrance, the amount of stones placed in nests, and the occlusion rates of the nest cavity entrances. Our data suggest that Rock Wrens place stones around their nests using selective, goal-directed behaviour with the objective of approaching an optimal cavity entrance size. Stone use at nests reflects high behavioural flexibility, and can be considered tool use during nest construction.