Causes of interspecific variation in growth rates within and among geographic regions remain poorly understood. Passerine birds represent an intriguing case because differing theories yield the possibility of an antagonistic interaction between nest predation risk and food delivery rates on evolution of growth rates. We test this possibility among 64 Passerine species studied on three continents, including tropical and north and south temperate latitudes. Growth rates increased strongly with nestling predation rates within, but not between, sites. The importance of nest predation was further emphasized by revealing hidden allometric scaling effects. Nestling predation risk also was associated with reduced total feeding rates and per-nestling feeding rates within each site. Consequently, faster growth rates were associated with decreased per-nestling food delivery rates across species, both within and among regions. These relationships suggest that Passerines can evolve growth strategies in response to predation risk whereby food resources are not the primary limit on growth rate differences among species. In contrast, reaction norms of growth 10 Present address:

Basic and applied disciplines rooted in ecology and evolution traditionally rely on experiential field instruction to teach key learning outcomes representing natural history, study design, field methods, and the process of scientific inquiry (Fleischner et al., 2017; Herman, 2002; Tewksbury et al., 2014). Other disciplines, such as the geosciences, similarly rely upon field activities in instruction (Whitmeyer & Mogk, 2009). Field activities, defined here as educational activities that occur outside and involve interaction with the natural or built environment (Fleischner et al., 2017), can provide unique and engaging instruction that is often vital to learning outcomes of postsecondary courses, even when they represent a relatively small portion of instruction (Harland, Spronken-Smith, Dickinson, & Pickering, 2006; Hole, 2018). Potential impacts of reduction and elimination of field activities and natural history education from undergraduate curricula have been previously recognized (Tewksbury et al., 2014) as have potential solutions (Fleischner et al., 2017). Despite its potential importance, biology education research appears to have paid relatively little attention to postsecondary field teaching compared to classroom teaching (Singer, Nielsen, & Schweingruber, 2013) or relative to other disciplines (e.g. geography; Boyle et al., 2007). The COVID-19 pandemic (Fauci, Lane, & Redfield, 2020) has clearly posed a unique set of challenges to higher education

Rapid growth in off‐highway vehicle (OHV) use in North America leads to concerns about potential impacts on wildlife populations. We studied the relationship between distance to active OHV trail and songbird nesting success and abundance in northeastern California, USA, from 2002 to 2004. We found evidence of greater nest desertion and abandonment and reduced predation on shrub nests <100 m from OHV trails than at nests >100 m from OHV trails. Two of 18 species studied were less abundant at sites on trails than at sites 250 m from trails, and no species were more abundant on trails. Management of OHV trail development should consider possible negative impacts on nesting success and abundance of breeding birds.

Education in ecology and evolution often utilizes field instruction to teach key learning outcomes. Remote teaching of learning outcomes that have been traditionally taught in the field, necessitated by the COVID-19 pandemic, presents unique challenges for students, instructors, and institutions. A survey of 117 faculty conducted during spring 2020 revealed substantial reduction of learning outcomes typically taught in the field, and frequent substitutions of less active and more instructor-centered remote activities for field activities. The survey revealed generally negative instructor views on many remote teaching substitutions, yet also showed several approaches that instructors regarded as more effective, despite potential challenges with equitably teaching them. I suggest several models of remote substitutions for traditional field teaching of identification, field techniques, data collection, and study design in the context of the results of this survey.

Molt is an energetically costly process, and songbirds (Order Passeriformes) exhibit a diversity of strategies to maximize their survival and reproductive success while meeting the energetic demands of the annual prebasic molt. Nearctic‐Neotropic migrants in western North America commonly exhibit one of three strategies: (1) remain in breeding areas to molt, (2) migrate long distances to molt before continuing to wintering areas, or (3) migrate to wintering areas and then molt. Among species that molt in or near breeding areas, the nature of small‐scale movements to undergo molt remains largely unknown. We used banding data collected over a period of 27 yr and across an elevational gradient to examine the propensity of Wilson's Warblers (Cardellina pusilla) to molt and breed at the same or different locations in northern California and southern Oregon. We found that individual adult Wilson's Warblers were more likely to breed at lower elevations and molt at higher elevations, suggesting that some individuals move altitudinally after breeding to complete the definitive prebasic molt. Such altitudinal movements may be more common among Nearctic‐Neotropic migrants in western North America than previously thought.