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In vertebrate ecology, a majority of studies focus on the breeding season of the study population (Marra et al. 2015). In avian ecology in particular, more is known about the ecology of birds during the nesting season than during any other portion of their life cycle (Harrison et al. 2011). The breeding season comprises only one small portion of an individual’s full annual cycle, which also includes the post-fledging period (from nesting to autumn migration), migration to wintering grounds, non-breeding season, and the migration back to the breeding grounds. These relatively understudied portions of the annual cycle have similar, or potentially greater, importance with regards to individual population-level ecology (Harrison et al. 2011). Even when events outside the nesting season do not contribute directly to mortality, they may influence individuals in a non-lethal manner during a subsequent portion of the annual cycle, a process known as carry-over effects (Norris 2005). In many migratory birds, there are few studies on migration and the non-breeding season, but for even more species there also remains a gap in knowledge about the post-fledging period. This period is arguably the relatively “low-hanging fruit” of the annual cycle outside of nesting ecology due to its importance in the annual cycle. In species that are of conservation concern, gaining knowledge about the full annual cycle could illuminate factors expediting population declines that would otherwise be unknowable. Red-headed Woodpeckers (Melanerpes erythrocephalus) are charismatic cavity-nesters that breed in open forest systems across the eastern and midwestern United States and southern portions of central and eastern Canada. They are closely associated with oak savanna ecosystems throughout the midwestern United States because of the open canopies and low understories for the aerial foraging of insects, scavenging of tree mast, and abundance of dead limbs and trees for cavity-nesting (Brawn 2006, Frei et al. 2015). Once common throughout their range, a range-wide population decline of 70% has been seen in the past 50 years (Sauer et al. 2013). Many factors have been hypothesized to contribute to this decline including the loss of open forest systems and the removal of dead trees that could be potential nesting habitat (Smith 1986), increased rates of predation due to elevated Accipiter populations (Koenig et al. 2017), increased competition for nesting cavities from introduced species such as starlings (Graber et al. 1977), and mortalities resulting from vehicle collisions while aerially foraging (Eifrig 1937). A combination of some or all of these hypotheses is most likely responsible. Despite their charismatic appearance, Red-headed Woodpeckers are an under-studied species with a lack of understanding about several key stages of their full annual cycle including migration (Smith et al. 2000) and the post-fledging period (Frei et al. 2015). Migration is a behavior found throughout the natural world that allows individuals or populations to avoid potential negative effects and take advantage of seasonal changes in resources. Migration comprises two portions of the annual cycle (Marra et al. 2015). Migration is typically divided into two categories: obligate migration, which occurs regularly and is considered “hard-wired” (Berthold 2001, Newton 2012); and facultative which occurs irregularly and is considered to be “optional” (Berthold 2001). This irregularity of facultative migration presents unique problems when attempting to study the behavior, and as such, little is known about the intrinsic and extrinsic factors controlling facultative migration (Berthold 2001). Facultative migration has been observed most notably in avian species, including the Common Crane (Alonso et al. 1994), Yellow-rumped Warblers (Terrill & Ohmart 1984), and Great Bustards (Streichet al. 2006), but occurs in insects including melon aphids (Kring 1959) and cotton bullworms (Zheng & Zhang 2000). Current understanding of facultative migration suggests that variation in resource availability and seasonality are the cues (i.e., they underlie the triggering) for facultative migration. In Red-headed Woodpeckers, facultative migration has primarily been described anecdotally (Smith et al. 2000) with few banding records indicating that fall migration occurs at varying spatio-temporal scales (USGS 2019). Most empirical data regarding Red-headed Woodpecker migration has been a result of a single study in South Carolina, which used radio telemetry to track the migration routes of short distance migration (

Genetic variation was examined in two endangered mussel species, Epioblasma brevidens and E. capsaeformis, and a common species Lampsilis fasciola, in the Clinch River, TN, by screening mitochondrial DNA (mtDNA) sequences and nuclear DNA microsatellites. These species use fish hosts with varying dispersal capabilities, ranging from low, moderate, and high, respectively. Patterns of mtDNA polymorphism exhibited different trends for long-term population sizes for each species during the Holocene (~10,000 ya to present); namely, E. brevidens has declined over time, E. capsaeformis has remained stable, and L. fasciola has expanded. Long-term effective population size (Ne) was smallest in E. brevidens, intermediate in E. capsaeformis, and highest in L. fasciola. Moderately diverged mtDNA lineages, perhaps indicative of secondary contact, were observed in E. brevidens and E. capsaeformis. High levels of gene flow (Nm) were estimated among demes of L. fasciola using traditional F-statistics and likelihood estimates of Nm, whereas such metrics were lower in E. brevidens and E. capsaeformis. Data are consistent with population dynamics and life history traits of each species and their fish hosts. Age, shell growth, and population demography of Epioblasma brevidens, E. capsaeformis, and Lampsilis fasciola were studied from 2004-2007 in a 32-km reach of the Clinch River, TN. Observed maximum age and length of E. brevidens was 28 y and 71.5 mm for males and 11 y and 56.6 mm for females; of E. capsaeformis, 12 y and 54.6 mm for males and 9 y and 48.6 mm for females; and of L. fasciola, 45 y and 91.3 mm for males and 13 y and 62.6 mm for females. For all three species, observed maximum age and length was greater among males than females. Estimated population size in this river reach was approximately 43,000 individuals for E. brevidens, 579,000 individuals for E. capsaeformis, and 30,000 individuals for L. fasciola. Mean recruitment y-1 of 1 y-old E. brevidens ranged from 7.1% to 20%, of E. capsaeformis from 4.0% to 32.4%, and of L. fasciola from 5.8% to 25.6%. Population growth rate y-1 was 24.9% for E. brevidens, 34.6% for E. capsaeformis, and -22.4% for L. fasciola. Mortality rates of females were higher than for males of E. capsaeformis and L. fasciola, but not E. brevidens. Juvenile mussels were collected but temporally and spatially variable in occurrence, and a significant component of the age-class structure of all three species. Recruitment was very high during 2006-2007 for E. capsaeformis and other species, likely due to low river discharges in the spring-summer of 2005-2007. Surplus individuals of E. brevidens and E. capsaeformis are currently available to conduct translocations for restoration purposes. Population modeling of Epioblasma brevidens and E. capsaeformis in the Clinch River was conducted to determine suitable harvest levels for translocation of sub-adults and adults, and to determine quantitative criteria for evaluating performance and recovery of extant and reintroduced populations. For both species, the recommended annual harvest was