Daniel Twedt, Ph.D. (Former Employee)

The Mississippi River Alluvial Valley includes the floodplain of the Mississippi River from Cairo, Illinois, USA, to the Gulf of Mexico. Originally this region supported about 10 million ha of bottomland hardwood forests, but only about 2.8 million ha remain today. Furthermore, most of the remaining bottomland forest is highly fragmented with altered hydrologic processes. During the...

Habitat quality is determined not only by habitat structure and the availability of resources, but also by competitors, cooperators, predators, and parasites. We hypothesized that, for passerines, minimizing risk from avian nest predators and brood parasites is an important factor in selecting a breeding site. Through the early part of two breeding seasons, we spot-mapped locations of...

In the Lower Mississippi Valley, more than 300,000 acres of agricultural land have been reforested in the last 10 years. Planning decisions on how and where to restore forest are complex and usually reflect landowner objectives. However, initial planning decisions may have a large influence on the value of restored stands for birds and other wildlife. Reforestation of small, isolated...

Reforestation of bottomland hardwood sites in the Mississippi Alluvial Valley has markedly increased in recent years, primarily due to financial incentive programs such as the Wetland Reserve Program, Partners for Wildlife Program, and state and private conservation programs. An avian conservation plan for the Mississippi Alluvial Valley proposes returning a substantial area of cropland...

Planned restoration of bottomland hardwoods is important to adequately address negative consequences resulting from the severe loss and fragmentation of forested wetlands in the Mississippi Alluvial Valley. Reforestation efforts have been promoted through government initiatives of state and federal agencies (e.g. Wetland Reserve Program) and private conservation groups. To clarify...

Thousands of ha of cleared wetlands are being reforested annually in the Mississippi Alluvial Valley (MAV). Despite the expansive and long-term impacts of reforestation on the biological communities of the MAV, there is generally a lack of landscape level planning in its implementation. To address this deficiency we used raster-based digital data to assess the value of forest restoration...

Land managers are often concerned with providing habitat affords the 'best habitat for songbirds.' However, unless management simply is directed at rare species it may not be clear which habitats or management options are best. A standard, quantifiable measure to compare the significance of different tracts of land or competing management techniques for avian conservation would benefit...

In December 2004, February 2005, and June 2005, we recaptured a White-eyed Vireo (Vireo griseus) that was banded on 19 May 2004 at the same location on the Tensas River National Wildlife Refuge, Madison Parish, LA. This is the first documented permanent resident White-eyed Vireo outside of resident populations known from Florida and southern Texas. This individual appears to be resident...

Of the forested wetlands that once covered the Mississippi Alluvial Valley, only -25% remain due to large-scale conversion to agriculture. Reforestation efforts are currently underway, but tracts planted with slow-growing oaks maintain the structure of a grassland for 5 yr or longer, and will require at least 40 yr to resemble a mature forest. Nonetheless, it is hoped that reforestation...

No abstract available.

Reforestation of bottomland hardwood sites in the southeastern United States has markedly increased in recent years due, in part, to financial incentives provided by conservation programs. Currently >250,000 ha of marginal farmland have been returned to hardwood forests. I observed establishment of trees and shrubs on 205 reforested bottomlands: 133 sites were planted primarily with oak...

I identified sexual dimorphism in wing length (unflattened chord) of Carolina Wrens (Thryothorus ludovicianus) within the central Mississippi Alluvial Valley (northeast Louisiana and west-central Mississippi) and used this difference to assign a sex to captured wrens. Wrens were identified as female when wing length was less than 57.5 mm or male when wing length was greater than 58.5 mm.