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The Conservation Reserve Program (CRP) has the potential to influence the distribution and abundance of grasslands in many agricultural landscapes, and thereby provide habitat for grassland‐dependent wildlife. Greater prairie‐chickens (Tympanuchus cupido pinnatus) are a grassland‐dependent species with large area requirements and have been used as an indicator of grassland ecosystem function; they are also a species of conservation concern across much of their range. Greater prairie‐chicken populations respond to the amount and configuration of grasslands and wetlands in agriculturally dominated landscapes, which in turn can be influenced by the CRP; however, CRP enrollments and enrollment caps have declined from previous highs. Therefore, prioritizing CRP reenrollments and new enrollments to achieve the greatest benefit for grassland‐dependent wildlife seems prudent. We used models relating either lek density or the number of males at leks to CRP enrollments and the resulting landscape structure to predict changes in greater prairie‐chicken abundance related to changes in CRP enrollments. We simulated 3 land‐cover scenarios: expiration of existing CRP enrollments, random, small‐parcel (4,040 m2) addition of CRP grasslands, and strategic, large‐parcel (80,000 m2) addition of CRP grasslands. Large‐parcel additions were the average enrollment size in northwestern Minnesota, USA, within the context of a regional prairie restoration plan. In our simulations of CRP enrollment expirations, the abundance of greater prairie‐chickens declined when grassland landscape contiguity declined with loss of CRP enrollments. Simulations of strategic CRP enrollment with large parcels to increase grassland contiguity more often increased greater prairie‐chicken abundance than random additions of the same area in small parcels that did not increase grassland contiguity. In some cases, CRP enrollments had no or a negative predicted change in greater prairie‐chicken abundance because they provided insufficient grassland contiguity on the landscape, or increased cover‐type fragmentation. Predicted greater prairie‐chicken abundance increased under large‐parcel and small‐parcel scenarios of addition of CRP grassland; the greatest increases were associated with large‐parcel additions. We suggest that strategic application of the CRP to improve grassland contiguity can benefit greater prairie‐chicken populations more than an opportunistic approach lacking consideration of the larger landscape context. Strategic implementation of the CRP can benefit greater prairie‐chicken populations in northwestern Minnesota, and likely elsewhere in landscapes where grassland continuity may be a limiting factor. © 2020 The Wildlife Society. We evaluated the potential effects of strategic versus opportunistic addition to an agricultural landscape of Conservation Reserve Program grasslands and wetlands in northwestern Minnesota, USA, on measures of abundance of greater prairie‐chickens. We suggest that strategic addition of large parcels of grassland and wetland in proximity to existing habitat has the greatest potential to benefit greater prairie‐chickens. [ABSTRACT FROM AUTHOR]

Both the abundance of greater prairie‐chickens (Tympanuchus cupido pinnatus) and the area of grassland enrolled in the Conservation Reserve Program (CRP) in northwestern Minnesota, USA, have recently declined. Although wildlife conservation is a stated objective of the CRP, the impact of the CRP on greater prairie‐chicken populations has not been quantified. To address that information need, we evaluated the association between greater‐prairie chicken lek density (leks/km2), the number of males at leks (males/lek), and CRP enrollments in the context of landscape structure and composition in northwestern Minnesota. Using data from standardized prairie‐chicken surveys and land cover in 17 41‐km2 survey blocks during 2004–2016, we used a mixed‐effect model and a layered approach in an information‐theoretic framework at multiple spatial scales to identify covariates related to prairie‐chicken abundance. At the landscape scale, lek density was best explained by the amount of CRP grassland and wetland, grassland and wetland with long‐term conservation goals (state, federal, and The Nature Conservancy owned); other wetlands managed with variable or no continuity in conservation goals; the contiguity of grasslands; and the number of patches of grasslands and wetlands in each survey block each year. Increasing the amount of CRP grassland in 41‐km2 survey blocks by 1 km2 (2.4%) resulted in a corresponding increase of 6% in lek density. At the lek scale, the number of males per lek was best explained by the amount of CRP grassland and other grassland, CRP wetland and other wetland, forests, developed areas, shrubland, and the contiguity of CRP grassland. Increasing the amount of CRP grassland in the 2‐km breeding‐cycle habitat radius around a lek by 25% (3 km2) corresponded to a 5% increase in males per lek. Our results suggest that both increasing the quantity of grassland CRP and wetland CRP enrollments and aggregating CRP grassland enrollments may increase greater prairie‐chicken abundance. © 2019 The Wildlife Society. Our models indicated that lek density and a number of males per lek of greater prairie–chickens were related to the amount and configuration of Conservation Reserve Program (CRP) enrollments in the agricultural landscape of northwestern Minnesota, USA. Our results suggest that increasing the quantity of grassland CRP and wetland CRP enrollments and aggregating CRP grassland enrollments may increase greater prairie‐chicken abundance. [ABSTRACT FROM AUTHOR]

Many amphibian populations are declining, and increased understanding of the drivers of amphibian presence and abundance will help in their conservation. In 2005 and 2006 we estimated relative abundance of larvae of two common amphibian taxa, Tiger Salamanders (Ambystoma tigrinum) and ranid tadpoles (Northern Leopard Frog Lithobates pipiens and Wood Frog Lithobates sylvaticus), in 75 shallow lakes in prairie and parkland areas in Minnesota. We used a two-step procedure in which we first modeled presence-absence with data from all lakes and then modeled abundance only in lakes where the amphibian taxa were present. For the two amphibian taxa, a generalized linear mixed effects model was used to examine the effects of dynamic factors like fish abundance and static (timeframe of study) variables like fish community type, depth, and adjacent land cover. Fish variables had the greatest influence but differed for the presence and abundance models. Salamander and tadpole presence was inversely correlated to the abundance of benthivorous fish, while salamander abundance was best explained by total fish abundance and tadpole abundance by fish community type. We did not detect influences of land cover types on the amphibian taxa we surveyed. Our findings are important because they complement previous studies documenting that negative correlations with fish extend beyond piscivores to include both planktivores and benthivores. Hydrological changes in our study landscape (e.g., installation of drainage networks, wetland consolidation) associated with agriculture and other land uses have likely increased the distribution and abundance of fish populations, thus dampening amphibian breeding success. [ABSTRACT FROM AUTHOR]

Background: Childhood trauma exposure has been associated with deficits in cognitive functioning. The influence of timing of exposure on the magnitude and persistence of deficits is not well understood. The impact of exposure in early development has been especially under-investigated. This study examined the impact of interpersonal trauma exposure (IPT) in the first years of life on childhood cognitive functioning. Methods: Children (N=206) participating in a longitudinal birth cohort study were assessed prospectively for exposure to IPT (physical or emotional abuse or neglect, sexual abuse, witnessing maternal partner violence) between birth and 64 months. Child intelligent quotient (IQ) scores were assessed at 24, 64 and 96 months of age. Race/ethnicity, gender, socioeconomic status, maternal IQ, birth complications, birth weight and cognitive stimulation in the home were also assessed. Results: IPT was significantly associated with decreased cognitive scores at all time points, even after controlling for socio-demographic factors, maternal IQ, birth complications, birth weight and cognitive stimulation in the home. IPT in the first 2 years appeared to be especially detrimental. On average, compared with children not exposed to IPT in the first 2 years, exposed children scored one-half SD lower across cognitive assessments. Conclusion: IPT in early life may have adverse effects on cognitive development. IPT during the first 2 years may have particular impact, with effects persisting at least into later childhood. [ABSTRACT FROM AUTHOR]

Constraints on lake communities are complex and are usually studied by using limited combinations of variables derived from measurements within or adjacent to study waters. While informative, results often provide limited insight about magnitude of simultaneous influences operating at multiple scales, such as lake- vs. watershed-scale. To formulate comparisons of such contrasting influences, we explored factors controlling the abundance of predominant aquatic invertebrates in 75 shallow lakes in western Minnesota, USA. Using robust regression techniques, we modeled relative abundance of Amphipoda, small and large cladocera, Corixidae, aquatic Diptera, and an aggregate taxon that combined Ephemeroptera-Trichoptera-Odonata (ETO) in response to lake- and watershed-scale characteristics. Predictor variables included fish and submerged plant abundance, linear distance to the nearest wetland or lake, watershed size, and proportion of the watershed in agricultural production. Among-lake variability in invertebrate abundance was more often explained by lake-scale predictors than by variables based on watershed characteristics. For example, we identified significant associations between fish presence and community type and abundance of small and large cladocera, Amphipoda, Diptera, and ETO. Abundance of Amphipoda, Diptera, and Corixidae were also positively correlated with submerged plant abundance. We observed no associations between lake-watershed variables and abundance of our invertebrate taxa. Broadly, our results seem to indicate preeminence of lake-level influences on aquatic invertebrates in shallow lakes, but historical land-use legacies may mask important relationships. [ABSTRACT FROM AUTHOR]

It is well accepted that moose (Alces alces) often use early successional habitats in the boreal forest. It is not clear, however, whether use of disturbed habitats represents a preference or simply that moose are more detectable. Previous research based on visual observations assumed that moose were equally detectable in all cover types. We evaluated habitat selection of moose in north- eastern Minnesota using telemetry locations and Land-Use Land-Cover (LULC) type information. We calculated measures of habitat selection within their home range (third-order) and selection of habitats to create a home range (second-order) using a technique called composition analysis. The analyses indicated that the Cutover cover type ranked highest in summer and winter in both second- and third-order selection and its rank generally was significantly higher than most other cover types. Selection for aquatic habitats during the summer was not evident in our analysis. Cover types that could provide lower operative temperatures from shade ranked higher than aquatic cover types. Inferences from these analyses should be treated with caution because of inherent weaknesses of use-availability analyses and biases associated with VHF telemetry locations. [ABSTRACT FROM AUTHOR]

Cost considerations may be as important as precision when making survey-design choices, and the ability to accurately estimate survey costs will be essential if survey budgets become more constrained. We used data from a survey of ring-necked ducks (Aythya collaris) to illustrate how simple distance formulas can be used to construct a cost function for aerial quadrat surveys. Our cost function provided reasonable estimates of effort (hr) and costs, and allowed us to evaluate plot-size choices in terms of expected cost-precision tradeoffs. Although factors influencing costs in wildlife surveys can be complicated, we believe that cost functions deserve more attention and should be routinely considered in conjunction with traditional power analyses. [ABSTRACT FROM AUTHOR]

Phytoplankton abundance in shallow lakes is potentially influenced by ambient phosphorus concentrations, nutrient loading accentuated by human activities in lake watersheds, and abundance of planktivorous and benthivorous fish. However, few studies have simultaneously assessed the relative importance of these factors influencing phytoplankton abundance over large spatial scales. We assessed relative influences of watershed characteristics, total phosphorus concentrations, and fish biomass on phytoplankton abundance in 70 shallow lakes in western Minnesota (USA) during summer 2005 and 2006. Our independent variables included total phosphorus (TP), benthivore biomass, planktivore biomass, summed planktivore and benthivore biomass (summed fish), areal extent of agriculture in the watershed, region (prairie versus parkland lakes), and year. Predictive models containing from one to three independent variables were compared using an information theoretic approach. The most parsimonious model consisted of TP and summed fish, and had over 10,000-fold greater support compared to models using just TP or summed fish, or models comprised of other variables. We also found no evidence that relative importance of predictor variables differed between regions or years, and parameter estimates of TP and summed fish were temporally and spatially consistent. TP and summed fish were only weakly correlated, and the model using both variables was a large improvement over using either variable alone. This indicates these two variables can independently increase phytoplankton abundance, which emphasizes the importance of managing both nutrients and fish when trying to control phytoplankton abundance in shallow lakes., (© 2013.)