Waterbird Use of Sheetwater Wetlands in Iowa’s Prairie Pothole Region

Large expanses of land across midcontinental North America have been heavily modified by installation of artificial drainage to convert prairie pothole wetlands into tillable areas. Drained potholes are observed as sheetwater wetlands in agricultural fields, are valued by migratory waterbirds, and have only been studied in limited contexts. We evaluated the use of agricultural sheetwater to migratory waterbirds in Iowa’s Prairie Pothole Region and hypothesized that wetland size would be an important predictor of waterbird use. We observed 1913 unique wetlands and documented waterbird use on 31% of observations of those wetlands. The most frequently detected waterbirds were Killdeer, Mallard, Blue-winged Teal, and Lesser Yellowlegs. Wetland size had a positive effect (P \u3c0.05) on waterbird species richness and abundance. The findings from this study will help inform future decisions on drainage practices and their impact on wildlife and indicate the need to examine this habitat type at larger temporal and spatial scales

Effect of cultivar and soil characteristics on nutritional value in organic and conventional wheat

Evidence of greater nutritional value in organic crops is currently a subject of intense debate. Our objectives in this study were to test for grain mineral concentration in 35 winter wheat cultivars in paired organic and conventional systems, and to determine the influence of cultivar, soil characteristics and farming system on mineral concentration. Here we report preliminary results that show that the grain mineral concentration in organic wheat was higher for copper (Cu), magnesium (Mg), manganese (Mn), phosphorus (P) and zinc (Zn) and lower in calcium (Ca), than the grain mineral concentration in conventional wheat. No difference was found between systems for iron (Fe) concentration. Cultivar was significant in determining mineral concentration for Ca, Cu, Mg, Mn and P. Soil mineral concentration was not responsible for grain mineral concentration, with the exception of P. The organic wheat farming systems had higher grain mineral concentrations of Cu, Mg, Mn, P and Zn than the conventional systems, possibly due in part to increased soil organic matter and pH in the organic systems. Growing specific cultivars capable of exploiting particular soil conditions may be necessary in order to optimize the nutritional value in organic farming systems

Strategic Flexibility and SMEs: The Role of Information Technology for Managing Internal and External Relations

The purpose of the current study was to assess the impact of information technology on strategic flexibility for small- and medium-sized enterprises (SMEs). Results of the study show that under conditions of low environmental dynamism, IT capabilities are associated with greater reactive strategic flexibility. Specifically, IT capabilities enabling the management of internal activities was significant. Under conditions of high environmental dynamism, IT capabilities are associated with greater proactive strategic flexibility. Specifically, IT capabilities enabling the management of competitor information was significant. Managerial as well as future research implications are discussed

Small Business Internet Use and Strategic Flexibility

Research on SME Internet use has focused almost exclusively on factors leading to the adoption of Internet technologies. In this study, we focus on the potentially valuable connection between Internet use and strategic flexibility. Specifically, we propose that Internet use for communications will promote greater strategic flexibility for the small firm, but only in a dynamic environment. The results, based on a sample of 160 small Midwest companies, largely support this hypothesis. Environmental dynamism was found to moderate the relationship between Internet use for communications and strategic flexibility. Use of the Internet for communications was found to be positively and significantly related to strategic flexibility in a dynamic environment. As expected, dynamism did not moderate the relationship between Internet use for transactions and strategic flexibility. These findings hold implications for future research and for managers of small firms attempting to effectively leverage the Internet for competitive advantage

Pathologic Features of the Intervertebral Disc in Young Nova Scotia Duck Tolling Retrievers Confirms Chondrodystrophy Degenerative Phenotype Associated With Genotype.

Chondrodystrophy results in predictable and progressive biochemical and structural changes to the intervertebral disc, resulting in early onset degeneration and dystrophic mineralization of the disc. Accelerated degeneration and mineralization of the intervertebral disc are common in multiple dog breeds and can result in compromised function, herniation, pain, and a variety of neurological sequelae. A mutation responsible for chondrodystrophy in dogs has been identified as an aberrant fibroblast growth factor 4 (FGF4) retrogene insertion on chromosome 12 (CFA12) and is associated with short stature of the Nova Scotia Duck Tolling Retriever. Segregation of the CFA12 FGF4 retrogene in this dog breed provides an opportunity to examine the effect of retrogene presence on radiographic and histologic appearance of chondrodystrophic disc degeneration within a single breed. Here we found that in the intervertebral discs isolated from 2 dogs with the CFA12 FGF4 genotype, the nucleus pulposus was largely replaced by cartilaginous tissue, and physaliferous notochordal cells were rarely if ever identified. These findings are in contrast to the normal histologic findings in 2 breed-matched dogs lacking the mutation. The findings are consistent with premature chondroid degeneration of the intervertebral disc and suggest that the presence of the CFA12 FGF4 retrogene is sufficient to cause the chondrodystrophic phenotype

Patterns of Monarch Site Occupancy and Dynamics in Iowa

The monarch butterfly (Danaus plexippus) is the focus of large-scale habitat restoration efforts because of recent population declines. From 2006-2017 we monitored monarchs at >400 sites throughout Iowa to link site occupancy and colonization/extinction dynamics to the presence of milkweed, site-specific habitat metrics, and landscape context at differing spatial scales. We used a robust design occupancy model in Program MARK and a hierarchical model selection approach to estimate site occupancy, extinction and colonization probabilities, and detection probability. Occupancy models revealed that monarchs responded differently to landscape features, environmental conditions, and local habitat conditions for site occupancy, extinction, and colonization probabilities. For site occupancy, the mean patch size of grassland at the 1-km spatial scale had a positive effect (βGrassPS1K = 0.94, SE = 0.54) while the percent of the landscape in woodland at the 200-m spatial scale had a negative effect (βWoodPL200 = −1.68, SE = 0.34). For extinction, there were additive effects of the percent of the landscape in woodland at the 100-m spatial scale (βWoodPLAND100 = 2.70, SE = 0.63), the interspersion of grassland at the 1-km spatial scale (βGrassIJI1K = −2.30, SE = 0.63), and litter depth (βLitter = 0.46, SE = 0.13). Finally, there were negative effects of the percent of the landscape in woodland at the 200-m spatial scale (βWoodPLAND200 = −4.67, SE = 1.37) and the interspersion of grassland at the 100-m spatial scale (βGrassPS1K = −2.02, SE = 0.70) on colonization probability. Detection probability was affected by the additive effects of canopy cover and monarch density; no other detection model was competitive. In the top model there was a positive effect of monarch density (βDensity = 0.28, SE = 0.05) and a negative effect of canopy cover (βCanopy = −0.18, SE = 0.03) on detection probability. In Iowa, monarchs are widespread on conservation lands where they avoid sites with lots of canopy cover. Colonization and extinction processes are influenced by an interplay of landscape attributes across multiple spatial scales and site habitat attributes. Our study provides the first comprehensive insight into monarch use of conservation lands in Iowa, and predicted responses to important covariates may be useful for future conservation efforts

Design Implications for Surveys to Monitor Monarch Butterfly Population Trends

The Iowa Multiple Species Inventory and Monitoring (MSIM) Program includes a protocol for monitoring butterfly density on conservation lands using transects. Most data are collected from sites chosen randomly; additional sites are chosen non-randomly for other reasons. We analyzed a 12-year dataset for monarchs to address how density (per 50 m2 transect section) responded to site selection (random vs. non-random), latitude, and measures of the amount of milkweed and canopy cover on survey transects. Between 2006 and 2017, we conducted 2,328 surveys on 420 sites and detected a total of 2,757 adult monarchs. Monarch densities peaked in 2010 for random sites and 2012 for non-random sites, but densities were lowest in 2013 for both site types. The density of monarchs at non-random transects (0.047, 95% CI = 0.031, 0.062) was higher than that at random transects (0.029, 95% CI = 0.019, 0.044) and the temporal trends of density for random and non-random sites were significantly different. Monarch density was positively correlated with UTM northing, suggesting that monarch density increases from south to north in Iowa. The percent of plots containing milkweed was positively correlated with monarch density whereas percent tree canopy cover was negatively correlated with monarch density. Our results show that non-random transects had more monarchs, which may be a concern when interpreting findings from some citizen science efforts that used non-probabilistic sampling designs. Collectively, the MSIM program data provide a comprehensive assessment of monarch densities statewide as well as the first empirically-derived density estimates for monarchs on the breeding grounds and may prove helpful when refining future monitoring efforts