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Nest success is an important parameter affecting population fluctuations of wild turkeys (Meleagris gallopavo). Factors influencing mammalian predation on turkey nests are complicated and not well understood. Therefore, we assessed nest hazard risk by testing competing hypotheses of Merriam's turkey (M. g. merriami) nest survival in a ponderosa pine (Pinus ponderosa) ecosystem during 2001–2003. We collected nesting information on 83 female Merriam's turkeys; annual nest success averaged 50% for adult females (range = 45–59%) and 83% for yearling females (range = 75–100%). Proportional hazard modeling indicated that precipitation increased the hazard of nest mortality. However, estimated hazard of nest predation was lowered when incubating females had greater shrub cover and visual obstruction around nests. Coyotes (Canis latrans) were the primary predator on turkey nests. We hypothesize that precipitation is the best predictor of nest survival for first nests because coyotes use olfaction effectively to find nesting females during wet periods. Temporally, as the nesting season progressed, precipitation declined and vegetation cover increased and coyotes may have more difficulty detecting nests under these conditions later in the nesting period. The interaction of concealment cover with precipitation indicated that nest hazard risk from daily precipitation was reduced with greater shrub cover. Management activities that promote greater shrub cover may partially offset the negative effects of greater precipitation events.

Because quantity and quality of roosting habitat can affect Merriam's Wild Turkey (Meleagns gallopavo merriami) distribution, we described habitat characteristics of Merriam's turkey roost sites in the southern Black Hills of South Dakota. Varying proportions of Merriam's turkeys in the southern Black Hills depended on supplemental feed from livestock operations during the 2 winters of our study, whereas the remainder wintered in forested habitat away from supplemental feed. We compared characteristics of roost habitat occupied by female turkeys from both groups. We located turkeys with radio-transmitters in the early morning and late evening to find roost sites. Female Merriam's turkeys in the southern Black Hills roosted exclusively in ponderosa pine trees, primarily on the upper portions of ridges on easterly aspects. Generally, trees >30 cm diameter at breast height (dbh) were chosen for roosting, but turkeys also roosted in trees with smaller dbh. During winter months, turkeys that relied on supplemental feeding roosted adjacent to the ranch-farmstead where the supplemental food was located. Generally, these turkeys used the same roost site(s) throughout the winter, whereas turkeys that remained in the forest during winter used multiple roost sites. We suggest maintaining stands of trees >30 cm dbh on the upper portions of easterly aspects to provide suitable roosting habitat for female Merriam's Wild Turkeys in the southern Black Hills.

Severe winter weather in the Northern Great Plains of North America can alter availability of winter cover and cause increased mortality of ring-necked pheasants (Phasianus colchicus). We monitored pheasant survival and habitat use via radiotelemetry during the second most severe winter in eastern South Dakota since 1892. We captured and radiomarked 48 female ring-necked pheasants at the onset of the 1996-97 winter and monitored survivors through spring at 3 sites in eastern South Dakota. We also monitored 58 female ring-necked pheasants at the same sites during the 1995-96 winter, a winter characterized by below average temperature and average snowfall (winter severity rank: 35th). Survival of radiomarked hens in 1995-96 (0.61 [SE = 0.07]) was higher (P < 0.001) than that in 1996-97 (0.03 [SE = 0.02]). Mortality due to predation was higher (P ≤ 0.042) than mortality due to weather in both winters. Mortality due to weather did not differ (P = 0.787) between winters. However, 31 of 41 deaths occurred during blizzard periods in 1996-97, indicating severe weather increased the vulnerability of pheasants to predation. Radiomarked hens showed the highest preference for tall grass (>75 cm), cattail (Typha spp.) wetland, and corn food plot habitats in winter 1995-96, and early winter 1996-97. Shelterbelt and corn food plot ranked highest for pheasants that survived to the second half of the 1996-97 winter. We conclude that shelterbelt and food plot habitats are essential to the survival of pheasants in eastern South Dakota during extreme winter weather conditions.

Birds with both eastern and western distributions occur in the Black Hills of western South Dakota. This forest is mostly ponderosa pine (Pinus ponderosa) and is managed for timber. Logging alters forest characteristics and the bird community. We studied habitat relations of breeding songbirds at the stand- and site-level scales in ponderosa pine and quaking aspen (Populus tremuloides)/paper birch (Betula papyrifera) forest. Sixty bird species were observed ≤50 m from count points. Species richness was greater in aspen/birch than in ponderosa pine. Species richness was generally lower in ponderosa pine with >40% overstory canopy cover (OCC) than in ponderosa pine with ≤40% OCC and than aspen/birch of any structural stage. Seven bird species were associated with the ponderosa pine, while four species were associated with aspen/birch. Bird associations at the stand-level were further refined by OCC and diameter-at-breast-height (DBH) structural stage of each forest type. Habitats for most birds in the Black Hills can be managed using current forest inventory descriptions that include OCC and DBH. However, Red-naped Sapsuckers (Sphyrapicus nuchalis), Red-breasted Nuthatches (Sitta canadensis), White-breasted Nuthatches (S. carolinensis), Ovenbirds (Seiurus aurocapillus), and Western Tanagers (Piranga ludoviciana) were strongly associated with site-level vegetation characteristics. Snag density, snag condition, and deciduous trees beneath the ponderosa pine canopy should be included in forest inventories to better quantify habitats for these birds.

Wood duck (Aix sponsa) populations have been increasing in the Central Flyway, but little is known about wood duck brood rearing in prairie ecosystems. We compared movements and habitat use of radiomarked female wood ducks with broods in South Dakota on 2 rivers with contrasting prairie landscapes. The perennial Big Sioux River had a broad floodplain and riparian forest, whereas the intermittent Maple River had emergent vegetation along the river channel. Movements between nest sites and brood-rearing areas were longer on the Maple River than on the Big Sioux River (P = 0.02) and were among the longest reported for wood duck broods. Movements on the Big Sioux River were longer in 1992 (P = 0.01), when the floodplain was dry, than in 1993 or 1994. Before flooding occurred on the Big Sioux River, broods used semipermanent wetlands and tributaries outside the floodplain; thereafter, females selected forested wetlands along the river. Broods on the Maple River used emergent vegetation along the river channel throughout the study. Because median length of travel to brood-rearing areas was 2-3 km, we recommend maintenance of brood-rearing habitat every 3-5 km along prairie rivers. Wildlife managers should encourage landowners to retain riparian vegetation along perennial rivers and emergent vegetation along intermittent streams to provide brood-rearing habitat during wet and dry cycles.

Rio Grande wild turkeys (Meleagris gallopavo intermedia) were trapped in Oklahoma and released in northeastern South Dakota during the early 1970s. Based on wintering counts, this population peaked at over 1000 birds in the mid 1980s, but steadily declined to <200 in 1996. This decline prompted the introduction of eastern wild turkeys (M. g. silvestris), which were indigenous to southeastern South Dakota, as a replacement subspecies. We compared nest site characteristics of translocated eastern wild turkeys with those of established Rio Grande wild turkeys. Over a 2 y period we radio-marked 23 eastern females, and 21 Rio Grande females. Eastern females initiated 45 nests, whereas Rio Grande females initiated 41 nests. Vegetation type selection for nest sites (e.g., woodland, grassland and shrub) did not differ between Rio Grande and eastern wild turkeys (P = 0.96). However, turkey nest sites (subspecies pooled) differed from paired reference sites by having: (1) more nest sites directly under shrubs (P < 0.001) within woodlands and shrublands, (2) more trees within 1 m of the nest bowl (P = 0.001) in woodlands and (3) greater cover above the nest bowl (P = 0.007) within grasslands and shrublands. Frequency of vegetation types selected by female wild turkeys of both subspecies as nest sites differed (P = 0.001) from the frequency of vegetation types randomly sampled. Although shrub vegetation types were least available, females selected shrub vegetation types (primarily western snowberry [Symphoricarpos occidentalis]) for the majority (53%) of nest initiations. Other nests were divided between woodlands (27%) and grasslands (20%). Nest success was not correlated with vegetation type.

We studied the survival and reproduction of a newly introduced population of Eastern Wild Turkeys (Meleagris gallopavo silvestris) during 1999 and 2000 to determine the adaptability of this subspecies to a minimally wooded (<10%) region located north of their recorded historic distribution in South Dakota. During 1999 and 2000, the South Dakota Department of Game, Fish and Parks (SDGFP) released 111 female and 25 male turkeys from Iowa and Kentucky onto a study area in northeastern South Dakota. We used radio telemetry to monitor survival and reproduction of the females for 2 years after their initial release. Annual survival for 71 females averaged 67%. Seasonal survival was lowest in fall and highest in winter. Mortality agents included avian and mammalian predators, haying equipment, automobiles, and unknown causes. Nesting rate for the 2 years averaged 93%, and renesting rate of turkeys with failed 1st-nest attempts averaged 45%. Nest success for all nests was 50%, and 62% of females attempting to nest each year were successful in at least 1 attempt. Predation was the primary cause of nest failure during both years. Overall, 72% of brooding females successfully raised ≥1 poult to 4 weeks post-hatch while individual poult survival to 4 weeks post-hatch averaged 36%. Despite <10% woodland cover, Eastern Wild Turkeys appeared to thrive in a glacial escarpment topography north of their historic range in the northern plains.

Phorate is a toxic organophosphorus insecticide that has been associated with accidental wildlife poisonings. Because of concern for effects on waterfowl, we studied the effects of phorate on mallard (Anas platyrhynchos) ducklings in littoral mesocosms in South Dakota wetlands. In each of 3 wetlands, we constructed 4 mesocosms. One mesocosm was a control, and to the others we applied phorate at rates of 1.2, 2.4, and 4.8 kg/ha, respectively. Phorate caused mortality to ducklings at all concentrations. Ducklings in control mesocosms (0.0 kg/ha) survived longer (P < 0.05) than those in treated mesocosms. Ten-day-old ducklings were more sensitive (P < 0.05) to phorate than were 21-day-old ducklings. Brain and blood cholinesterase (ChE) activity of treated ducklings was reduced (P < 0.01) compared with that of reference ducklings. Phorate concentrations in prairie wetlands can reduce duckling survival; therefore, alternatives to phorate should be considered.

Overwater nesting structures placed in prairie wetlands provide attractive and secure nesting sites for mallards (Anas platyrhynchos). However, survival of ducklings hatched on overwater structures is poorly documented and yet critical in evaluating their contribution to mallard recruitment. We evaluated survival of mallard broods and ducklings produced on overwater nesting structures in eastern South Dakota during springs and summers 1998-1999. We chose 3 study sites with overwater structures, representing a large (∼400-ha) semi-permanent wetland (Mickelson), a medium-sized (∼140-ha) semi-permanent wetland (Redetzke), and a mosaic of seasonal, semi-permanent, and permanent wetlands (Oakwood). We radiomarked 86 females and 58 day-old ducklings during the study. Brood and duckling survival was high, ranging 0.71-1.0 and 0.42-0.73, respectively. Survival was notably low (0.02) for ducklings produced on one small semi-permanent wetland at Oakwood that was surrounded by large trees, but particularly high (0.73) for ducklings produced at the Mickelson site. We suggest that large hemi-marsh sites with either natural or controlled water regimes promoting interspersion of emergent vegetation may provide safe and attractive places for female mallards to rear their broods and convenient locations for managers to place and maintain large numbers of overwater structures. In prairie or other nonforested landscapes, we recommend that resource managers not consider placing overwater structures in small wetlands surrounded by trees and lacking emergent cover. Additionally, where waterfowl production is a primary management goal, we recommend that wetland enhancement or restoration efforts in these landscapes not include establishment of trees.

Nests of radiotransmittered wild turkeys (Meleagris gallopavo) that are destroyed or abandoned prior to incubation are particularly difficult to locate. As a result researchers often report only incubated nests or estimate numbers of nests attempted by localization of movement or other behavioral changes without quantification. We used radiotelemetry to obtain movement data on female wild turkeys during the nesting season (1 Apr-30 Jun) in South Dakota. We collected prelaying (1 April until 14 days before the female initiated incubation) and laying (<14 days before incubation) movement distances from 160 adult female wild turkeys [75 eastern (M. g. silvestris), 19 Rio Grande (M. g. intermedia), and 66 Merriam's (M. g. merriami) wild turkeys]. Our objectives were to quantify the relationship between movement behavior and nesting attempts to allow more accurate determination of initiation of nesting for calculation of nest rates, nesting success, and renesting rates. Daily movements of females decreased abruptly when they transitioned from prelaying to laying behaviors. Movements of females that were less than 364.9 m for eastern turkeys, 115.0 m for Rio Grande turkeys, and 331.0 m for Merriam's turkeys were indicative of nest initiation. Changes in movements of females can identify nesting wild turkeys and can be used post hoc to identify nests that were abandoned or destroyed prior to incubation if sufficient locations are collected. Following our analysis, we estimated that females had an additional 46 nests (eastern = 15, Rio Grande = 7, and Merriam's = 24), which we used in estimating reproduction parameters. Quantitative comparisons of movements between prelaying and laying confirmed a behavioral change of localized movements concurrent with nest initiation in wild turkey females.