Climate forcing of regional fire years in the upper Great Lakes Region, USA

Background. Drivers of fire regimes vary among spatial scales, and fire history reconstructions are often limited to stand scales, making it difficult to partition effects of regional climate forcing versus individual site histories. Aims. To evaluate regional-scale historical fire regimes over 350 years, we analysed an extensive fire-scar network, spanning 240 km across the upper Great Lakes Region in North America. Methods. We estimated fire frequency, identified regionally widespread fire years (based on the fraction of fire-scarred tree samples, fire extent index (FEI), and synchronicity of fire years), and evaluated fire seasonality and climate-fire relationships. Key results. Historically, fire frequency and seasonality were variable within and among Great Lakes' ecoregions. Climate forcing at regional scales resulted in synchronised fires, primarily during the late growing season, which were ubiquitous across the upper Great Lakes Region. Regionally significant fire years included 1689, 1752, 1754, 1791, and 1891. Conclusions. We found significant climate forcing of region-wide fire regimes in the upper Great Lakes Region. Implications. Historically, reoccurring fires in the upper Great Lakes Region were instrumental for shaping and maintaining forest resilience. The climate conditions that helped promote widespread fire years historically may be consistent with anticipated climate-fire interactions due to climate change

The North American tree-ring fire-scar network

Fire regimes in North American forests are diverse and modern fire records are often too short to capture important patterns, trends, feedbacks, and drivers of variability. Tree-ring fire scars provide valuable perspectives on fire regimes, including centuries-long records of fire year, season, frequency, severity, and size. Here, we introduce the newly compiled North American tree-ring fire-scar network (NAFSN), which contains 2562 sites, >37,000 fire-scarred trees, and covers large parts of North America. We investigate the NAFSN in terms of geography, sample depth, vegetation, topography, climate, and human land use. Fire scars are found in most ecoregions, from boreal forests in northern Alaska and Canada to subtropical forests in southern Florida and Mexico. The network includes 91 tree species, but is dominated by gymnosperms in the genus Pinus. Fire scars are found from sea level to >4000-m elevation and across a range of topographic settings that vary by ecoregion. Multiple regions are densely sampled (e.g., >1000 fire-scarred trees), enabling new spatial analyses such as reconstructions of area burned. To demonstrate the potential of the network, we compared the climate space of the NAFSN to those of modern fires and forests; the NAFSN spans a climate space largely representative of the forested areas in North America, with notable gaps in warmer tropical climates. Modern fires are burning in similar climate spaces as historical fires, but disproportionately in warmer regions compared to the historical record, possibly related to under-sampling of warm subtropical forests or supporting observations of changing fire regimes. The historical influence of Indigenous and non-Indigenous human land use on fire regimes varies in space and time. A 20th century fire deficit associated with human activities is evident in many regions, yet fire regimes characterized by frequent surface fires are still active in some areas (e.g., Mexico and the southeastern United States). These analyses provide a foundation and framework for future studies using the hundreds of thousands of annually- to sub-annually-resolved tree-ring records of fire spanning centuries, which will further advance our understanding of the interactions among fire, climate, topography, vegetation, and humans across North America

Disentangling fire, climate, forest structure, and land-use history interactions in Mexico's northern Sierra Madre

2012 Summer.Includes bibliographical references.The 20th century was a period of profound changes in climate, land-use, forest structure, and fires throughout much of western North America and few montane forests continue to function under historical influences of climate variations and uninterrupted fire regimes. Yet, if we are to manage for resilient forests, understanding these linkages is critical and will depend on both pre-1900 and 20th century observations. My research takes advantage of a unique opportunity in northern Mexico to study forest and fire dynamics before a century of fire exclusion. My research documented a shift in climate - fire relationships in the late 19th century toward an overwhelming importance of antecedent moisture, unlike that seen previously for > 200 years. Tree recruitment peaks were tied to local processes, not broad-scale climate conditions. Antecedent wet conditions that promote fire occurrence suggests that in arid regions of the Southwest, anomalously wet years, still functioning under frequent fire occurrence, may further limit tree recruitment. The importance of fire induced mortality in shaping stand structure underscores the spatial variability of forests and helps explain even-age patches in forests as an artifact of patch survival of seedlings that recruit into the overstory

FALL MIGRATION CHRONOLOGY AND HABITAT USE OF THE AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION

My thesis describes data we collected on habitat use and migration chronology of woodcock in the western Great Lakes Region. I hope this work will assist in defining management practices that might help alleviate woodcock declines.Meunier, Jed. (2005). FALL MIGRATION CHRONOLOGY AND HABITAT USE OF THE AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/183586

Appendix C. Examples of age structure distribution for three different plots that demonstrate (a) uneven age structure, (b) a flat even-age cohort establishing around 1900, and (c) a flat even-age cohort establishing around 1950.

Examples of age structure distribution for three different plots that demonstrate (a) uneven age structure, (b) a flat even-age cohort establishing around 1900, and (c) a flat even-age cohort establishing around 1950

Appendix B. Scaling relationships for predicting diameter at breast height (dbh) from measurements of diameter sample height (dsh, 10 cm) for remnant wood.

Scaling relationships for predicting diameter at breast height (dbh) from measurements of diameter sample height (dsh, 10 cm) for remnant wood

FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2003 FIELD SEASON REPORT

Declines in the number of American woodcock (Scolopax minor) heard on annual singing ground surveys have resulted in concern regarding the population status of woodcock in both the Central and Eastern Management Regions. Although changes in the distribution and abundance of woodcock habitat are believed to largely be responsible for apparent population declines, relatively little is known regarding the influence of harvest on woodcock population dynamics. Similarly, movements and habitat use of woodcock in fall prior to migration are poorly understood. In 2001 (Minnesota) and 2002 (Michigan and Wisconsin), we initiated a study of woodcock to assess magnitude and causes of woodcock mortality, and investigate movements and habitat use of woodcock in the western Great Lakes Region during fall. In all 3 states, we radio-marked woodcock on paired study areas; one of which was open to woodcock hunting (“hunted areas”) and one of which was closed (“non-hunted areas”) to hunting or had limited access for hunting (“lightly-hunted areas”). In 2003, across all 3 states we captured and radio-equipped 338 woodcock; 194 on hunted areas and 144 on non-hunted or lightly-hunted areas. Survival rates of woodcock during the 2003 hunting season in Michigan were 0.778 + 0.157 in the hunted area and 0.857 + 0.240 in the non-hunted area. In Minnesota, the hunting season survival rate of woodcock in the hunted area was 0.733 + 0.303, and in the non-hunted area it was 0.854 + 0.155. In Wisconsin, the hunting season survival rates of woodcock were 0.657 + 0.151 in the hunted area and 0.735 + 0.151 in the lightly hunted area. A sub-sample of after hatch year (AHY) female woodcock was monitored intensively in each state and preliminary analyses of movement and habitat use data from these birds suggest that woodcock make primarily small-scale movements (47.7% <50 m between subsequent locations and 5.82 ha average 95% fixed kernel home range size) prior to migration. Primary cover types used were aspen (Populus spp.) seedling/sapling, aspen pole, alder (Alnus spp.), conifer, and willow (Salix spp.). Preliminary analyses also suggest that woodcock used edges within individual covers, but that use of edge habitats is variable among habitat types and years.Andersen, David E; Bruggink, John G; Doherty, Kevin; Lutz, R.Scott; Meunier, Jed; Oppelt, Eileen. (2004). FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2003 FIELD SEASON REPORT. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/183518

FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2004 FIELD SEASON REPORT

Declines in the number of American woodcock (Scolopax minor) heard on annual singing ground surveys have resulted in concern regarding the population status of woodcock in both the Central and Eastern Management Regions. Although changes in the distribution and abundance of woodcock habitat are believed to largely be responsible for apparent population declines, relatively little is known regarding the influence of harvest on woodcock population dynamics. Similarly, movements and habitat use of woodcock in fall prior to migration are poorly understood. In 2001 (Minnesota) and 2002 (Michigan and Wisconsin), we initiated a study of woodcock to assess magnitude and causes of woodcock mortality, and investigate movements and habitat use of woodcock in the western Great Lakes Region during fall. In all 3 states, we radio-marked woodcock on paired study areas; one of which was open to woodcock hunting (“hunted areas”) and one of which was closed (“non-hunted areas”) to hunting or had limited access for hunting (“lightly-hunted areas”). From 2001-2004 across all 3 states we captured and radio-equipped 1,169 woodcock; 594 on hunted areas and 575 on non-hunted or lightly-hunted areas. Preliminary survival estimates during the hunting season ranged from 0.639 ± 0.150 (hunted area in Wisconsin in 2003) to 0.900 ± 0.228 (hunted area in Minnesota in 2001) and were generally higher in non-hunted than in hunted areas. However, survival estimates between study sites in the same state during the same year were not statistically different from one another, except in 2 instances. Survival was variable among years and sites, but highest in hunted areas, suggesting that hunting mortality may vary more than other causes of mortality. A sub-sample of after-hatch-year (AHY) female woodcock was monitored intensively in each state and analyses of movement and habitat use data from these birds suggest that woodcock make primarily small-scale movements (47.7% <50 m between subsequent locations and 5.82 ha average 95% fixed kernel home range size) prior to migration. Primary cover types used were aspen (Populus spp.) seedling/sapling, aspen pole, alder (Alnus spp.), conifer, and willow (Salix spp.). Preliminary analyses also suggest that woodcock used edges within individual covers, but that use of edge habitats is variable among habitat types and years.Andersen, David E; Meunier, Jed; Bruggink, John G; Oppelt, Eileen; Lutz, R.Scott; Doherty, Kevin. (2005). FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2004 FIELD SEASON REPORT. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/183523

FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2002 FIELD SEASON REPORT

Declines in the number of American woodcock (Scolopax minor) heard on annual singing ground surveys have resulted in concern regarding the population status of woodcock in both the Central and Eastern Management Regions. Although changes in the distribution and abundance of woodcock habitat are believed to largely be responsible 1 2002 Field Season Report · July 2003 2 for apparent population declines, relatively little is known regarding the influence of harvest on woodcock population dynamics. Similarly, movements and habitat use of woodcock in fall prior to migration are poorly understood. In 2001 (Minnesota) and 2002 (Michigan and Wisconsin), we initiated a study of woodcock to assess magnitude and causes of woodcock mortality, and investigate movements and habitat use of woodcock in the western Great Lakes Region during fall. In all 3 states, we radio-marked woodcock on paired study areas; one of which was open to woodcock hunting (“hunted areas”) and one of which was closed (“non-hunted areas”) to hunting or had limited access for hunting (“lightly-hunted areas”). In 2002, across all 3 states we captured and radio-equipped 376 woodcock; 203 on hunted areas and 173 on non-hunted or lightly-hunted areas. Survival rates of woodcock during the hunting season in Michigan were 0.839 + 0.270 in the hunted area and 0.909 + 0.219 in the non-hunted area. In Minnesota, the hunting season survival rate of woodcock in the hunted area was 0.764 + 0.140, and in the non-hunted area it was 0.929 + 0.093. In Wisconsin, the hunting season survival rates of woodcock were 0.860 + 0.135 in the hunted area and 0.855 + 0.184 in the lightly hunted area. A sub-sample of after hatch year (AHY) female woodcock was monitored intensively in each state and preliminary analyses of movement and habitat use data from these birds suggest that woodcock make primarily small-scale movements (< 50 m between sequential locations on sequential days and 12.6 ha average 95% fixed kernel home range size) prior to migration. Primary cover types used were aspen seedling/sapling, aspen pole, alder, and conifer. Preliminary analyses also suggest that woodcock used edges within individual covers.Andersen, David E; Bruggink, John G; Doherty, Kevin; Lutz, Scott R; Meunier, Jed; Oppelt, Eileen. (2003). FALL SURVIVAL, MOVEMENTS, AND HABITAT USE OF AMERICAN WOODCOCK IN THE WESTERN GREAT LAKES REGION: 2002 FIELD SEASON REPORT. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/183516