We studied responses of breeding birds to alternative regimes for managing tallgrass prairie at the Smoky Hill Air National Guard Range in central Kansas. Species richness, diversity, and evenness did not differ among treatments, but overall abundance was highest in unburned idle (i.e., not grazed or hayed) transects, and was lowest in idle transects burned that spring. However, no treatment was either superior or inferior to all others for attracting the highest numbers of every species. Dickcissels (Spiza americana) and Henlow's sparrows (Ammodramus henslowii) were most numerous in unburned idle units, grasshopper sparrows (A. savannarum) were most abundant in grazed units and hayed units, upland sandpipers (Bartramia longicauda) were most often found in burned units, whereas eastern meadowlarks (Sturnella magna) were less abundant in burned units than in all other treatments. We conclude that the recent switch to burning idle units every 3–4 years, rather than annually, has benefitted most grassland bird species. The variety of management regimes implemented at Smoky Hill Air National Guard Range fosters heterogeneity of vegetative structure across the landscape, and thereby allows the site to provide for differing needs of various species, thus enhancing its value for grassland bird conservation.

It is often difficult to restore degraded lands within protected areas because of the high costs and because so little is known about the ecological requirements of the many species involved. Experience in Tam Dao National Park in northern Vietnam suggests the reforestation of degraded areas can be catalysed by simple monoculture plantations and that the cost of this may be modest. In this case, an existing Pinus massoniana Lambert plantation that was subsequently included within the national park was retained because native plant species were re-establishing in the understory. Within 20 years, a species-rich understory composed almost entirely of native species had established under the protective cover of the pines. This comprised 64 plant families, including 122 tree species, 46 shrubs, 33 vines, 2 herbs, 2 ferns, and 1 grass. Sixteen of these species were classified as threatened. Most of the colonists were most likely brought to the site from adjacent intact forest by wildlife over distances of up to 700 m. These plants were mostly small-seeded species, and many poorly-dispersed species remain absent from the site even after 70 years and will need assistance to colonize. The pines have persisted for 70 years, and some suggestions are made for managing the transition from a pine plantation with a native species understory to regrowth forest of solely native flora. This study suggests plantation monocultures may have a useful role in enhancing biodiversity in degraded areas within other protected areas - provided natural forest areas are close by.

The National Park Service (NPS) and other land management agencies have interest in managing bison herds under “natural” conditions; yet demographic features of natural populations are not well described. One solution to this issue involves the analysis of historical bison (Bison spp.) jump data. We conducted a literature search of archeological data associated with bison jump sites in North America with the goal of analyzing the data and summarizing historical bison demographics. We identified six locations with adequate information to conduct vertical life-table analyses. Two of the six were Bison antiques, two were Bison occidentalis, and the final two were Bison bison. In five of six analyses, a common annual survival parameter was estimated across all age classes. The most robust data set came from Wardell, Wyoming, where age-class-specific survival parameters best described the data. Average annual survival for the same age classes across all six sites was = 0.7344. These estimates are substantially lower than annual survival estimates of contemporary bison herds. The lower survival estimates produced an estimated finite rate of population change for Pre-Columbian B. bison of = 1.075 compared to contemporary populations that are about 9% higher. Natural Pre-Columbian B. bison populations had a much lower growth potential than contemporary populations due to pressures from apex predators, which are no longer present in current populations. Managers of natural areas interested in maintaining natural bison populations can use our results to help guide culling and other management decisions.

Identifying habitat preferences of species of concern is fundamental to the practice of conservation, but disturbances and other environmental processes can substantially affect suitability. Trifolium stoloniferum, or running buffalo clover, is a federally endangered plant species that occurs on the Fernow Experimental Forest in West Virginia. Previous work and extensive anecdotal evidence suggests that this species is maintained in part by periodic disturbances to its habitat. In the Fernow Experimental Forest, this disturbance is in the form of intermittent logging activities. We investigated the role of forest harvesting practices and environmental variables in fostering T. stoloniferum at the stand level. Censuses have been conducted on T. stoloniferum occurrences in the Fernow since 1994, and occurrences are grouped by subcompartment or watershed, which are the basic management units within this experimental forest. Site characteristics and disturbance history were assessed for their impact upon T. stoloniferum presence and density. Classification tree analysis identified total number of forest harvest events in a subcompartment since 1948 as the most important predictor of T. stoloniferum presence or absence. Regression tree analysis identified aspect as important in determining T. stoloniferum abundance, with west-facing compartments supporting larger populations. This study confirms the importance of disturbance in maintaining T. stoloniferum populations. However, site characteristics independent of disturbance history are also predictors of T. stoloniferum presence and abundance, suggesting that managers attempting to restore or create habitat for T. stoloniferum should account for the interaction between disturbance history and site characters in determining suitability of habitat for T. stoloniferum.

Hurricanes represent a major source of stochastic disturbance to coastal plant communities, with the potential to temporarily alter both species composition and environmental characteristics. Ceratiola ericoides Michx. (Florida rosemary) is a dominant member of an association of xeric species known collectively as rosemary scrub, which occur on barrier islands along the Gulf Coast and in inland peninsular Florida scrub. Unlike interior populations of Florida rosemary, which are periodically reduced by fire, coastal populations of rosemary are likely to be influenced by hurricanes more than by fire, with resultant differences in the frequency of damage to adults. We quantified the impact of major hurricanes on coastal populations of Florida rosemary and examined the impact of storm surge, elevation, and time-since-hurricane on rosemary survival and resprouting in five populations on the Mississippi and Florida coasts. Ratio of living-to-dead rosemary shrubs was higher in two coastal populations not recently struck by a major hurricane than on three barrier islands affected in 2004 – 2005 by Hurricanes Ivan and Katrina. There was also a trend toward greater mortality from Hurricanes Ivan and Katrina on islands with lower elevation, but the difference was not statistically significant, perhaps reflecting similar impacts of these hurricanes and their occurrence in consecutive years. In contrast to previous observations of infrequently disturbed inland populations of Florida rosemary, which exhibited an obligate seeder strategy, coastal populations showed a significant capacity for resprouting following hurricane damage. Given a two-year or more delay in seedling establishment following severe damage to adults, resprouting could expedite post-hurricane recovery of these populations.

Maritime forest communities on barrier islands along the Atlantic and Gulf coasts have been severely fragmented by a continuous history of human land use and natural disturbance. Isolated populations of certain tree species in maritime forest fragments may now be too small to be viable and their inability to regenerate may result in their eventual elimination from barrier islands. Using an 11-year study of a population of pignut hickory (Carya glabra), a common species of remnant maritime forest stands on St. Catherine's Island, Georgia, we present a case study of tree regeneration failure on a barrier island. We found that there has been no recruitment of new hickory individuals into the canopy of this population over the last 65 years. Field evidence of browse and a strong correlation between seedling density distributions and microsite protection from herbivory suggest that this trend in recruitment failure is related to an increased abundance of deer (Odocoileus) and pigs (Sus) on the island. Using a size class population projection model, we estimated that, if such recruitment failure and mortality rates continue, the hickory population will be extirpated from the maritime forest within 200 years. Tree species that are failing to regenerate within maritime forests represent a special challenge that is not currently being addressed in the long-term management of barrier island biodiversity.

In Mexico, little is known about species richness and distribution patterns of ferns and lycopods (Pteridophytes) in dry climates, since both groups have been studied mainly in wet environments. The Barranca de Metztitlán Biosphere Reserve, in the state of Hidalgo in central Mexico, is covered mostly with xerophytic vegetation and has a rugged landscape with contrasting climate areas. It was selected for this study as an appropriate model for analyzing changes in the composition, richness, and distribution of fern and lycopod species by elevation. To establish the relationship between species composition and richness along the elevation gradient, simple and multivariate correlation techniques were used (TWISPAN and detrended correspondence analysis). From a total of 464 specimens collected, 69 fern species and two hybrids, and eight lycopod species were identified. Three of the species had not previously been recorded for the state of Hidalgo: Pellaea atropurpurea, Thelypteris hispidula, and Selaginella illecebrosa. Species richness of both ferns and lycopods was positively correlated with elevation due to greater water availability and lower temperature. The species replacement rate between sites was high, indicating that ferns and lycopods grow in different associations along the elevation gradient. These associations can be regarded as indicators of environmental variation (primarily temperature and moisture) and/or vegetation types in the biosphere reserve.

Non-native invasive plants can negatively affect the abundance and survival of native plant species and alter ecosystem function. Amur honeysuckle (Lonicera maackii) is an invasive shrub that is an increasingly onerous problem for forest managers in eastern North America. We examined site-specific characteristics related to the presence and abundance of Amur honeysuckle, and other non-native invasive plants, in 15 second growth forests in central Kentucky. Individual remnants were characterized by: (1) frequency and cover of non-native invasive and native shrubs, (2) overstory tree basal area, (3) forest floor litter depth, (4) species composition of leaf litter, and (5) soil characteristics. Of the measured variables, the only statistically significant relationships we discovered were between Amur honeysuckle and characteristics of the forest floor. We found significant negative relationships between Amur honeysuckle presence and both forest floor litter depth (P = 0.01) and the percent of oak (Quercus spp.) litter on the forest floor (P = 0.004). The abundance (percent cover) of Amur honeysuckle was significantly and negatively related to forest floor litter depth (P = 0.03). These findings suggest that forest floor mass creates a barrier to invasion by exotic plants and that forests dominated by oak species may be more resistant to invasion by Amur honeysuckle. While this study did not identify a causal relationship between litter depth and oak litter and the presence of Amur honeysuckle, our findings do suggest that older forests, and those dominated by oak, may be more resistant to the invasion of Amur honeysuckle.

Fire suppression in sandhill ecosystems leads to biotic impoverishment and reduces fine fuels needed for frequent fires. We investigated the restoration dynamics of a long-unburned endemic-rich sandhill on Florida's Lake Wales Ridge using prescribed fire with and without prior chainsaw felling of the hardwood subcanopy. Our goals were to promote survival of longleaf pines (Pinus palustris), decrease subcanopy and shrub densities and lichen cover, and increase cover of graminoids and rare forbs. Treatments were applied in 2001 and responses monitored annually through 2005. Prior felling of the subcanopy increased fire temperatures, residence times, and coverage compared to the burn-only treatment. The saw and burn treatment was effective in removing the subcanopy, but caused an undesirable increase in longleaf pine mortality. Pine mortality decreased with distance from saw and burn plots. Post-treatment shrub densities initially decreased, then increased in both treatments relative to controls. Forb densities and graminoid cover increased in both treatments and controls; increases were greater with burn treatments. Both treatments, especially saw and burn, caused compositional shifts relative to the control. Subcanopy felling as a pre-treatment for burning was effective in beginning restoration. We recommend additional fires and protection of longleaf pines to continue restoration progress. Saw and burn treatments can accelerate restoration and are a good first step toward re-establishing a frequent low-intensity fire regime.

Nomenclature: Wunderlin and Hansen (2003) unless otherwise indicated

Grassland habitat is declining in the northeastern United States, leading to a decline in associated native species. Consequently, there is considerable interest by land managers in conserving and restoring grassland habitats in the Northeast. However, unlike the Great Plains and Europe, quantitative monitoring of restoration sites is uncommon, making it difficult to improve new restoration projects. Here we evaluate a grassland restoration in Waterford, Connecticut, to determine if mechanical clearing of woody vegetation combined with sowing 23 native grasses and forbs led to successful establishment of these species. We also compared cover, diversity, and colonization by exotic and woody species in planted and unplanted areas over time. In the third and fifth growing seasons after planting in 2006, we sampled the vegetation in the planted site, an unplanted zone within the planted grassland, and an adjacent unplanted grassland. Twenty of the 23 sown species established by 2010, and sown species dominated the planted area (70% of total cover). Despite the successful establishment of most sown species, species richness and diversity were no higher in the sown grassland than in adjacent unseeded areas. However, the sown grassland contained lower cover of non-native and invasive species. Big bluestem (Andropogon gerardii Vitman) established aggressively, potentially reducing both exotic colonization and native diversity. This study shows that sowing native grassland species can lead to the successful development of native-dominated grasslands. Results can inform future grassland restoration efforts in the Northeast and show that seeding with aggressive grass species may greatly impact restored plant communities.

The diverse uses of Ricinus communis L. (Castor bean) in herbalism, agriculture, and horticulture have facilitated the worldwide dispersal of this invasive r-selected species. A common element in ruderal areas and transitional habitats, the invasive species management of R. communis in southern California has largely relied on manual removal strategies. This study evaluates how the survivorship and fecundity of naturalized R. communis populations is impacted by the invasive species management strategies at two sites: Ballona Wetlands and Temescal Canyon Gateway Park. Our findings suggest that documenting patterns of survival and reproduction serve as a tool for the adaptive management of invasive species control strategies.