NATURAL RESOURCE SUPPLY CONSTRAINTS AND REGIONAL ECONOMIC ANALYSIS: A COMPUTABLE GENERAL EQUILIBRIUM APPROACH

A computable general equilibrium model is used to estimate the impact a resource supply constraint, that restricts federal timber harvest, has on a timber dependent region. Impacts are compared to impacts generated from an input-output mode and indicate an upward bias in estimated income and employment losses using IO methods.Resource /Energy Economics and Policy,

Investigations of Population Structure and Relative Abundance of Year-Classes of Buffalo Fishes, Ictiobus Spp., In Lake Sakakawea, North Dakota

This study was undertaken to investigate the population and abundance of year-classes of the buffalo fishes in Lake Sakakawea, North Dakota. Fish used in this study were obtained from Grasteit Dakota Fisheries, a commercial fishing operation headquartered in Newtown, North Dakota. Only bigmouth buffalo (Ictiobus cyprinelius) and smallmouth buffalo (Ictiobus bubalus) were collected during this study; no black buffalo (Iciobus niger) were captured. The age and growth of these fish was found to be quite similar to that in other Missouri River mainstem reservoirs. The mean condition factor (K-TL) for the bigmouth was found to be 1.88 and for the smallmouth was found to be 1.83. These values are higher than any reported for other mainstem reservoirs, and were probably due to the preponderance of large fish in our populations. The length-weight regression was calculated to be Log W = -3.63 + 2.60 log L for the bigmouths and Log W = -5.94 + 3.42 log L for the smallmouths. Lake Sakakawea reached full pool for the first time in 1967. Year-classes before this time are strong for both species of buffalo, making up over 73% of the smallmouths and over 69% of the bigmouths that were aged. After this full pool elevation was reached there was a dramatic decrease in year-class strength due to loss of optimal spawning areas. An exception was the 1969 year-class, which was of moderate strength, probably due to the fact that water levels were 0.8 feet above the full pool elevation

Use of the Case Study Method to Enhance the Educational Experience for Students

I have always believed in teaching with practical examples. However, I typically have presented these examples to students in a passive manner (i.e., a traditional lecture format). Because I was not pleased with retention of what I considered important material, I searched for a means to improve retention through more active learning while retaining practical examples. Thus, I first learned about the National Center for Case Study Teaching in Science (http://ublib.buffalo.edu/libraries/projects/ cases/ case.html) and attended their annual meeting

TOWARDS A COMPREHENSIVE REGIONAL WATER POLICY MODEL FOR THE TEXAS HIGH PLAINS

A 19 county, 50-year dynamic economic optimization model of irrigated crop production is linked to a detailed hydrology model for purposes of improving policy estimates of economic cost and associated water saving of groundwater conservation management policies. Spatial and temporal desegregation, allows planners to target specific areas and improve the accuracy of benefit-cost policy estimates.Resource /Energy Economics and Policy,

Effectiveness of Two Water Conservation Policies: An Integrated Modeling Approach

Agriculture in the Texas High Plains depends entirely on the Ogallala Aquifer. Texas enacted water conservation legislation to address declining reserves in the aquifer. We developed an integrated regional water policy model that links a hydrology model with an economic optimization model to estimate policy impacts with respect to economic cost and water conservation. Testing the effectiveness of two policies, a groundwater extraction tax and extraction quotas, we observe that neither significantly inhibits groundwater use. Although both policies conserve similar amounts of groundwater, the regional cost of the tax policy to agriculture is more than the quota policy.integrated regional water policy model, Texas High Plains, water conservation policy, hydrology model, economic optimization model, Ogallala Aquifer, tax policy, quota policy, Agribusiness, Community/Rural/Urban Development, Food Security and Poverty, Land Economics/Use, Political Economy, Q30, Q31, Q38,

Guide to the Common Fishes of South Dakota

South Dakota is home to more than 100 fish species. This guide is a reference to the most common 50 species. Included are tips for identification, distribution maps and brief life histories. Also included is a comprehensive listing of the known fish species in South Dakota

Mensurative Approach to Examine Potential Interactions Between Age-0 Yellow Perch (Perca flavescens) and Bluegill (Lepomis macrochirus)

Bluegill (Lepomis macrochirus) andyellow perch (Perca flavescens) populations are often sympatric in the Great Plains region of the U.S.A. and portions of Canada; however, very little attention has been given to potential interactions between these species for available resources, especially during the early life stages. Relationships between age-0 bluegill and yellow perch growth and relative abundance were explored across multiple lakes and years within the Nebraska Sandhill region, USA. In addition, four habitat patch types (open water, Phragmites spp., Typha spp., Scirpus spp.) were sampled for age-0 bluegill and yellow perch, and food habits were examined for each species during August, September, and October of 2009 in one of these lakes. Age-0 yellow perch growth was negatively related to age-0 bluegill relative abundance across a spatiotemporal scale. Age-0 bluegill and yellow perch exhibited similar habitat use (moderate–high overlap), but generally consumed different important and dominant prey taxa (bluegill consumed both macroinvertebrates— 56 % and zooplankton—44 %, while yellow perch consumed more zooplankton—66 %), which resulted in low overall diet overlap between species. Previous research indicates that age-0 yellow perch diet ontogeny often results in feeding predominately on macroinvertebrates and positively selecting them (and avoiding zooplankton prey) at sizes observed in our study. Therefore, yellow perch growth rates may be compromised by the presence of bluegill because of the need to consume less energetically profitable prey items such as zooplankton

Mensurative Approach to Examine Potential Interactions Between Age-0 Yellow Perch (Perca flavescens) and Bluegill (Lepomis macrochirus)

Bluegill (Lepomis macrochirus) andyellow perch (Perca flavescens) populations are often sympatric in the Great Plains region of the U.S.A. and portions of Canada; however, very little attention has been given to potential interactions between these species for available resources, especially during the early life stages. Relationships between age-0 bluegill and yellow perch growth and relative abundance were explored across multiple lakes and years within the Nebraska Sandhill region, USA. In addition, four habitat patch types (open water, Phragmites spp., Typha spp., Scirpus spp.) were sampled for age-0 bluegill and yellow perch, and food habits were examined for each species during August, September, and October of 2009 in one of these lakes. Age-0 yellow perch growth was negatively related to age-0 bluegill relative abundance across a spatiotemporal scale. Age-0 bluegill and yellow perch exhibited similar habitat use (moderate–high overlap), but generally consumed different important and dominant prey taxa (bluegill consumed both macroinvertebrates— 56 % and zooplankton—44 %, while yellow perch consumed more zooplankton—66 %), which resulted in low overall diet overlap between species. Previous research indicates that age-0 yellow perch diet ontogeny often results in feeding predominately on macroinvertebrates and positively selecting them (and avoiding zooplankton prey) at sizes observed in our study. Therefore, yellow perch growth rates may be compromised by the presence of bluegill because of the need to consume less energetically profitable prey items such as zooplankton

Larval Black Crappie Distribution: Implications for Sampling Impoundments and Natural Lakes

An understanding of larval fish distributions is essential for developing an appropriate sampling design to monitor larval abundances. We monitored abundance of larval black crappie Pomoxis nigromaculatus to assess spatial differences in Richmond Lake (a 336-ha impoundment) and Brant Lake (a 405-ha natural lake), South Dakota, during 1994–1996. Age-0 black crappies were collected with a 500-µm mesh ichthyoplankton trawl from fixed sites within each water body. In the impoundment, larval black crappies were collected over a longer period at the upper site than at the dam site during 1994 and 1995. In the natural lake, larval black crappie abundances were similar between east and west sites during all 3 years. In light of our results, biologists should spatially stratify sampling sites when collecting larval black crappies in impoundments such as Richmond Lake, whereas random sites may be more appropriate in natural lakes such as Brant Lake

The Impact of Spatial Variation in Land Use Patterns and Aquifer Characteristics on the Agricultural Cost of Groundwater Conservation for the Southern Ogallala Aquifer

Land Economics/Use,