The Effect of Local and Landscape-Level Characteristics on the Abundance of Forest Birds in Early-Successional Habitats during the Post-Fledging Season in Western Massachusetts

Abstract

Many species of mature forest-nesting birds (“forest birds”) undergo a pronounced shift in habitat use during the post-fledging period and move from their forest nesting sites into areas of early-successional vegetation. Mortality is high during this period, thus understanding the resource requirements of post-fledging birds has implications for conservation. Efforts to identify predictors of abundance of forest birds in patches of early-successional habitats have so far been equivocal, yet these previous studies have primarily focused on contiguously forested landscapes and the potential for landscape-scale influences in more fragmented and modified landscapes is largely unknown. Landscape composition can have a strong influence on the abundance and productivity of forest birds during the nesting period, and could therefore affect the number of forest birds in the landscape available to colonize early-successional habitats during the post-fledging period. Therefore, the inclusion of landscape characteristics should increase the explanatory power of models of forest bird abundance in early-successional habitat patches during the post-fledging period. We examined forest bird abundance and body condition in relation to landscape and habitat characteristics of 15 early-successional sites during the post-fledging season in Massachusetts. The abundance of forest birds was influenced by within-patch habitat characteristics, however the explanatory power of these models was significantly increased by the inclusion of landscape fragmentation and the abundance of forest birds in adjacent forest during the nesting period for some species and age groups. Our findings show that including factors beyond the patch scale can explain additional variation in the abundance of forest birds in early-successional habitats during the post-fledging period. We conclude that landscape composition should be considered when siting early-successional habitat to maximize its benefit to forest birds during the post-fledging period, and should also be included in future investigations of post-fledging habitat use by forest birds.

Songbird Use of Native and Invasive Fruit in the Northeastern USA

“…To determine whether birds selected fruits of either native or invasive species, we conducted foraging observations from July through early September at 10 sites during 2007 and 5 sites during 2008 (4 of which were also surveyed in 2007). This period coincided with the peak diversity and abundance of native and nonnative fruits in the region (Stiles 1980), as well as the peak in the abundance and diversity of birds in shrubland habitats, which are utilized by both shrubland and forest bird species (Labbe and King 2014). The study period also coincided with the postfledging or postbreeding seasonal lifecycle phase that occurs after nesting and before the onset of migration (Faaborg et al 1996; Vega Rivera et al 1998, 1999) and associated deposition of subcutaneous fat (Rappole and Ballard 1987).…”

The influence of local- and landscape-level factors on wetland breeding birds in the Prairie Pothole Region of North and South Dakota

“…However, the abundance of Red-winged Blackbird (a facultative wetland species that also nests in uplands) declined with the amount of wetlands in the landscape, whereas the abundance of the Yellow-headed Blackbird (an obligate wetland species that only nests in wetlands) declined in wetlands as the amount of grassland in the landscape increased. Many other studies have demonstrated the importance of both local-and landscapelevel factors on bird communities (for example, Naugle and others, 2000a; Cunningham and Johnson, 2006;Tsai, 2007;Niemuth and others, 2008;Clough and others, 2009;Roselli and Stiles, 2012;Labbe and King, 2014;Galitsky and Lawler, 2015).…”

Effects of forest management on the conservation of bird communities in eastern North America: A meta‐analysis

“…Our study focused only on avian abundance during the nesting period, and both mature‐forest and shrubland birds use early‐successional, harvested stands extensively during the post‐fledging period (Akresh et al, 2009; Chandler et al, 2012; Labbe & King, 2014). More species‐specific studies are needed in order to incorporate the post‐fledging period into meta‐analyses of bird relationships with tree retention (Cox et al, 2014).…”