Background Despite availability of valuable ecological data in published thematic maps, manual methods to transfer published maps to a more accessible digital format are time-intensive. Application of object-based image analysis makes digitization faster. Methods Using object-based image analysis followed by random forests classification, we rapidly digitized choropleth maps of white-tailed deer (Odocoileus virginianus) densities in the conterminous US during 1982 and 2001 to 2005 (hereafter, 2003), allowing access to deer density information stored in images. Results The digitization process took about one day each per deer density map, of which about two hours was computer processing time, which will differ due to factors such as resolution and number of objects. Deer were present in 4.75 million km2 (60% of the area) and 5.56 million km2 (70%) during 1982 and 2003, respectively. Population and density in areas with deer presence were 17.15 million and 3.6 deer/km2 during 1982 and 29.93 million and 5.4 deer/km2 during 2003. Greatest densities were 7.2 deer/km2 in Georgia during 1982 and 14.6 deer/km2 in Wisconsin during 2003. Six states had deer densities ≥9.8 deer/km2 during 2003. Colorado, Idaho, and Oregon had greatest increases in population and area of deer presence, and deer expansion is likely to continue into western states. Error in these estimates may be similar to error resulting from differential reporting by state agencies. Deer densities likely are within historical levels in most of the US. Discussion This method rapidly reclaimed informational value of deer density maps, enabling greater analysis, and similarly may be applied to digitize a variety of published maps to geographic information system layers, which permit greater analysis.

Pine (Pinus spp.) plantations are a common type of managed forest in the southeastern United States that may supply habitat for early successional bird species, many of which are declining. To provide information about young pine plantations as bird habitat, we evaluated spring bird presence in 5 combinations of stand establishment practices during years 2 through 5 post‐establishment in the Lower Coastal Plain of Mississippi, USA. We detected 38 species with point counts and compared bird metrics among establishment practices using mixed general linear models. Species richness, total relative abundance, and relative abundance of many species were greater by at least a factor of 1.5–4 in the chemical‐only establishment practice than mechanically prepared establishment practices, and values declined by about 5–60% within mechanically prepared establishment practices as herbicide intensity increased. Tree and snag retention contributed to avian abundance and richness in the chemical‐only establishment practice. Our study, in conjunction with past research, demonstrated the conservation value to early successional bird species of managed pine stands established with tree retention, indicating that silvicultural and wildlife habitat objectives can be met within the range of stand establishment treatments available to managers. © 2012 The Wildlife Society.

Pine plantation establishment methods can alter vegetation composition and structure, thus affecting habitat important characteristics for declining early successional bird species. We evaluated eight vegetation characteristics, which varied due to a range of pine plantation establishment methods, to identify vegetation most closely associated with spring bird abundance in the Lower Coastal Plain of southern Mississippi, USA. Presence of residual trees and snags was positively related to relative abundance of 10 of 14 common species present in regenerating stands. Cover of woody vegetation was positively related to relative abundance of 4 species and negatively related to relative abundance of 2 species. For 5 species, increasing pine tree cover had a negative relationship with relative abundance. Residual trees and snags contributed to avian abundance and richness in regenerating pine plantations. Integration of habitat elements, such as residual trees that influence abundance of birds and other wildlife, with intensive pine plantation establishment can aid managers to attain wildlife conservation in intensively managed stands

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Despite widespread interest in white-tailed deer (Odocoileus virginianus) in the southeastern United States, historical deer populations and densities have not been compiled into one accessible source. We digitized maps from 1950, 1970, 1982, and 2003 and reviewed literature to quantify population sizes and densities in the Southeast, although previous estimates may not be accurate. Deer population sizes declined to a minimum of <215,000 during the early 1900s. Population sizes and mean deer densities were 304,000 and 0.22 deer/km 2 by 1940, 476,000 and 0.35 deer/km 2 by 1950, 2.9 million to 4.1 million and 2.2 to 3.1 deer/km 2 by approximately 1970, 6.2 million and 4.6 deer/km 2 by 1982, and 10.8 million to 12 million and 8 to 9 deer/km 2 by about 2003. Although our estimates are likely not completely accurate in space and time, due to difficulty of counting animals, they provide the best available information and a range and trend in values, with general corroboration among sources. The current population size may be greater than during pre-Euro-American settlement, when based on minimum historical deer densities, or, conversely, the current population may be within the bounds of mid to high historical deer densities. Large deer densities trigger a research need to evaluate deer effects on vegetation, but threshold densities when deer are damaging to herbaceous plants may need to be reconsidered. Instead, we conjecture that deer may be considered a natural disturbance helpful in controlling increased tree densities during the past century, albeit placing a secondary stress upon declining herbaceous plants, which are losing ground to trees.