Once prevalent on the landscape, early-successional habitats are now increasingly threatened in the northeastern United States. As a result, many species that rely on or require habitats dominated by shrubs, young trees, grasses, and forbs have experienced precipitous population declines, leading many organizations to list shrubland habitats and constituent wildlife as a conservation priority. Even-aged forest management (e.g. clearcutting) has been shown to be an efficient and effective means for creating early-successional habitat for certain taxa such as shrubland birds, but it is unfeasible in many situations in southern New England due to public opinion and increased parcelization. Group selection harvests create shrubland conditions in the form of relatively small forest openings (< 1 ha); however, limited attention has been directed toward understanding the extent to which these methods contribute to conservation of early-successional species. In order to assess the conservation value of small forest openings for wildlife in southern New England, I studied two distinct communities associated with early-successional habitats, shrubland birds and bees (Hymenoptera: Apiformes), in openings created by group selection harvests and patch-cutting. In 2014 and 2015, birds were surveyed in small forest openings in western Massachusetts in an effort to describe relationships between species occurrence and patch area as well as other microhabitat-, patch-, and landscape-level variables. Black-and-white warblers, common yellowthroats, chestnut-sided warblers, eastern towhees, and gray catbirds were likely to be present in openings at least 0.3 ha in size, while indigo buntings and prairie warblers had minimum area requirements of 0.55 and 1.07 ha, respectively. Variables within microhabitat-, patch-, and landscape-levels were important for predicting species occurrence. Most notably, prairie warblers were more likely to occur in openings closer to large patches of habitat such as powerline corridors, even if those openings were small in size. I conclude that, despite their inability to support the entire community of shrubland birds in this region, small forest openings can provide habitat for several species of conservation concern if proper attention is given to promoting suitable microhabitat, patch, and landscape characteristics. Bees were sampled in openings as well as adjacent mature forest in an effort to describe the bee community, identify environmental variables influencing bee abundance and diversity, and examine the extent to which openings created by forest management may support bees, as well as potentially augment bee populations within adjacent unmanaged forest. Bees were significantly more abundant and diverse in forest openings than mature forest, but species composition was indistinguishable between openings and forest. Abundance and diversity displayed no relationship with opening size in either openings or forest, but were generally positively related to the amount of early-successional habitat on the landscape. Vegetation characteristics within openings were important in shaping bee communities in openings, with abundance and diversity decreasing with vegetation height and increasing with floral abundance. Notably, eusocial, soft-wood-nesting, and small bees exhibited the opposite pattern in adjacent forest, increasing with the succession of openings and decreasing with greater floral abundance within openings. These results suggest that the creation of small forest openings may help to promote bees both in openings and adjacent mature forest, but certain guilds may be negatively affected.

Early-successional habitats have become rare in much of the eastern United States, largely due to landuse change, forest maturation and the disruption of natural disturbance regimes. In addition to providing nesting habitat for shrubland species of high conservation concern, wildlife openings may be an important habitat for mature-forest birds during the postfledging period – a critical phase in the avian lifecycle with the potential for high mortality. The habitat requirements of birds during this time period are poorly understood. In this study I examined the relationship between habitat and landscape characteristics on; 1) the abundance of forest nesting birds in shrubland habitat during the postfledging season, and 2) the reproductive success of shrubland bird species. And lastly, I also examined the relationship between avian body condition and seed dispersal, with a focus on comparing native and invasive species. I found that the abundance of forest birds was strongly influenced by landscape characteristics, as well as food abundance and structurally complex vegetation. Shrubland birds varied in their response to habitat variables, but overall productivity was positively related to taller vegetation structure, and was negatively related to lower-dense vegetation. Frugivore diets were generalized, yet they selected native fruit more often than invasive fruit, and invasive fruit negatively affected condition. My findings are consistent with the results of previous studies of habitat use among postfledging birds, and suggest that, like for forest birds, habitat requirements for shrubland birds during the postfledging period differ from those during the nesting season. Hopefully these results will encourage other studies of this important, but poorly understood stage of the avian lifecycle.

In recent decades, New England agriculture has become increasingly characterized by small, diversified farming operations with values deeply rooted in community and conservation. In sharp contrast to large-scale, high-intensity agriculture currently typified by the majority of North American farms, New England farmers commonly prioritize ecologically beneficial production practices such as reduced chemical inputs, integrated pest management (IPM), low tillage, cover cropping and crop rotation, and retention of natural habitats like woody hedgerows and herbaceous strips. Public support and demand for local, sustainable food, evidenced by the success of CSA (Community Supported Agriculture) in the region, has helped to bolster this movement and increase the viability of these farms. In addition to boosting regional food production and self-sufficiency, these farms also present an opportunity for wildlife conservation. Shrubland bird species in particular may benefit from habitat created on these farms because of their preference for heterogeneous shrub and herbaceous vegetation and lower area sensitivity compared to other species, such as grassland obligates. In order to evaluate conservation potential and habitat associations of shrubland birds and other priority species on small, diversified farms, we conducted point counts and vegetation surveys across 23 farms in the Pioneer Valley, MA during the summers of 2017 and 2018. We used Poisson-binomial mixture models and canonical correspondence analysis (CCA) to assess the effects of a suite of microhabitat-, field-, and landscape-scale variables on the abundance of bird species. Our results confirmed that shrubland birds, including song sparrow (Melospiza melodia), gray catbird (Dumatella carolinensis), common yellowthroat (Geothlypis trichas) and American goldfinch (Spinus tristis), were the predominant species present, accounting for over 52% of the total observations. Species-habitat relationships were diverse; however, smaller field sizes, and increased cover of tall, dense, woody or nonproductive vegetation types were associated with higher abundance of shrubland species as well as lower abundance of crop pests such as European starling (Sturnus vulgaris) and house sparrow (Passer domesticus). These findings support the hypothesis that small, diversified farms are providing beneficial habitat for shrubland birds, as well as providing species-specific guidelines for farmers interested in conserving birds on their land. In order to place small, diversified farms into a regional conservation context and evaluate their contribution to shrubland bird conservation efforts in New England, we compared bird abundance, community composition, and conservation value of small, diversified farms to five established shrubland habitat types in the region: wildlife openings, two types of silvicultural openings (larger clearcuts and small forest openings created by group selection harvest), beaver meadows, and powerline rights-of-way. We compiled avian survey data from previous studies of each of the aforementioned habitat types conducted from 2002-2006 (powerline rights-of-way, wildlife openings, clearcuts, and beaver meadows) and 2014 (small forest openings). We then compared the relative bird abundance, community composition, and conservation value across all five habitat types (including farms) using Generalized Linear Models (GLMs), non-metric multidimensional scaling (NMDS) ordination, permutational multivariate analysis of variance (PERMANOVA), and calculated an Avian Conservation Significance (ACS) score for each habitat. The avian community composition of farms most closely resembled that of wildlife openings and harbored more open-habitat and generalist species such as American robin (Turdus migratorius), red-winged blackbird (Agelaius phoeniceus), and eastern kingbird (Tyrannus tyrannus). Several shrubland species were found to have higher relative abundances on farms than any of the other four habitats including song sparrow (Melospiza melodia), northern cardinal (Cardinalis cardinalis), and willow flycatcher (Empidonax traillii). Farms possessed a higher ACS score than powerline rights-of-way, small forest openings, and beaver meadows, but were lower than clearcuts and wildlife openings. Our results suggest that small, diversified farms support a unique suite of shrubland species, and while they certainly cannot replace managed shrubland habitats such as wildlife openings and clearcuts, they may complement these existing habitats in terms of their community composition and conservation value.

As shrubland bird populations decline, there is a critical need to understand the effects of habitat management. I studied a population of color-banded prairie warblers (Setophaga discolor) between 2008-2011 in a shifting mosaic landscape within a Massachusetts inland, pitch pine-scrub oak barren consisting of persistent, newly created, succeeding, and disturbed habitats. I present data showing that the abundance and population structure at this site appears to be a function of colonization of newly created habitat by second-year birds, which are likely excluded from mature early-successional habitat by site-faithful older birds. Breeding season fecundity did not differ significantly between newly-created and mature habitats. Birds displaced by mowing or fire dispersed to nearby suitable habitat the following year, had relatively similar reproductive success, and did not negatively affect pairing or reproductive success in adjacent areas. My findings are novel and show that the effects of shrubland management on shrubland birds are beneficial in the short- and long-term. I also examined prairie warbler nest-site selection and nest survival in relation to plant leafing phenology and other factors. Prairie warblers selected distinct nest sites and certain attributes of these selected sites increased nest survival; thus I conclude that nest-site selection is adaptive. Plant leafing phenology influenced nest-site selection and nest survival in this system; its effects on birds should be considered as a potential mechanism by which bird communities can be affected by global climate change.

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