Do Cerulean Warblers (Dendroica Cerulea) Exhibit Clustered Territoriality?

Nocturnal Predation of Females on Nests: An Important Source of Mortality for Golden-Cheeked Warblers?

“…Clustered nesting in all-purpose territories has been observed in at least five species of North Roth and Islam 2007). Clustered breeding may occur in some species for competitive exclusion, predator defense, use of patchy resources, or from social factors including increased potential for extra-pair copulations (reviewed in Tarof and Ratcliffe 2004).…”

“…Cues used as indicators of high quality habitat may include vegetation (Hildén 1965), presence of conspecifics (Stamps 1988, Ward andSchlossberg 2004), or both. Several studies have found that Least Flycatchers respond to song of conspecifics during settlement (Mills et al 2006, Fletcher 2007, but the first individual to arrive and begin singing in an appropriate habitat must be cued by something other than conspecific attraction (Roth andIslam 2007, but see Betts et al 2008). Least Flycatchers may be stimulated to settle in habitats, including red pine plantations, with a relatively closed canopy due to presence of deciduous trees.…”

“…Robins give two types of terrestrial alarm calls, yeeps and chucks. However, robins also have numerous aerial predators with accipiters (Cooper's Hawk [Accipiter cooperii] and Sharp-shinned Hawk [A. striatus]) being particularly important predators (Roth andLima 2003, Roth et al 2006) and, accordingly, an aerial alarm might provide a strong selective advantage. Currently there are conflicting reports in the literature concerning whether or not robins have an aerial alarm.…”

Long-distance Dispersal Patterns of Male Cerulean Warblers (Dendroica cerulea) Measured by Stable-hydrogen Isotopes

“…Results from this study suggest that most of these unbanded birds may represent relatively local recruitment at a spatial scale too narrow to be detected from δD analysis, and that only a few (one in this study) are long-distance immigrants. Given the tendency of adult Cerulean Warblers to cluster their breeding territories (Robbins et al 1992, Roth andIslam 2007), it is likely that conspecific Avian Conservation and Ecology -Écologie et conservation des oiseaux 2(2): 3 http://www.ace-eco.org/vol2/iss2/art3/ attraction is also used by adults when selecting new breeding habitats.…”

Think globally, manage locally: The importance of steady-state forest features for a declining songbird

“…(1) canopy structure -Cerulean Warblers respond primarily to the structure of the forest canopy and prefer tall canopies with gaps (canopy height + canopy openness), (2) tree size -Cerulean Warblers are positively associated with the numbers of large trees (number of large trees), (3) light gap -Cerulean Warblers respond positively to canopy openness and associated understory characteristics in gaps (number of understory stems + canopy openness), (4) forest structure -Ceruleans respond to a wide suite of forest structural features (understory stems + large trees + canopy openness + canopy height), (5) adjacency to harvestCerulean Warblers respond more strongly to the presence of an adjacent clear-cut than to local forest structure, and (6) the full model (all variables) based on previous studies of Cerulean Warbler habitat associations (Oliarnyk and Robertson, 1996;Weakland and Wood, 2005;Roth and Islam, 2007). We used a generalized linear model with a negative binomial distribution (Schabenberger and Pierce, 2002) to calculate log-likelihood estimates for each model (SAS Institute, 1996) and then calculated Akaike's Information Criterion corrected (AIC c ) for bias because of small sample size.…”