The Fish Population of Lake Poinsett, South Dakota, as Indicated By the Catch

Gill nets, trap nets, an otter trawl, and a boom-type electric shocker were utilized to obtain samples of the fish population of Lake Poinsett, South Dakota. The species and size composition of the samples differed significantly with time of season, time of day, location on the lake, and type of gear. Decreased activity following spawning was the apparent cause of a midsummer decline in gill net and trap net catches of black bullhead, black crappie, and white crappie. A late summer increase in the catch of yearling black bullheads, crappies, white bass, carp and bigmouth buffalo was attributed to an increase in activity or change in behavior pattern. Diurnal migrations were felt to be the cause of diel differences in catch rate of species taken by the trawl and shocker. Different age classes of fish apparently vary in their activity patterns. Uneven distribution of the population caused differences in the catch of each type of gear at different locations on the lake. Types of gear differed in their effectiveness for different species and sizes of fish. Each type of gear indicated a different population structure. Gear selectivity resulted from differences in fish behavior and physical characteristics of the sampling gear. The results of the study indicated· that: interpretation of population samples should be based on knowledge of the habits of species in the population, characteristics and limitations of the sampling gear, and of the body of water being sampled; collection of samples should be intensive and over a relatively long period of time; all habitats should be sampled; and at least two types of collecting gear should be used

Towards a Construct of Employment for Social Welfare and Economic Productivity

This article analyzes Marxian socialist, neo-classical, and Keynesian economic theories toward developing a construct of employment which supports social welfare and economic productivity. It considers their motivational approaches, outcomes, and requirements for social control. A Keynesian construct of employment is recommended as supportive of social well-being, high productivity, and a level of social control reduced from that in currently dominant economic systems. Implications and implementation issues are considered

Gender, Employment and Psychosocial Well-being

Although authors are increasingly addressing the specific needs of men and women at work, no theory based comparison of how employment affects their psychosocial well-being has been available. A six dimensional index was developed to explore a social exchange model of the associations among employment, psychosocial well-being, and worker productivity for men and women. Findings based on two samples of 41 (instrument pretest) and 143 (model test) employed and unemployed union workers suggest strong reliability and validity estimates for the index, support for the model, high explanatory power, and different results for men and women. Implications for further research and recommendations for developing employment programs to enhance gender specific social well-being and worker productivity are discussed

Towards a Construct of Employment for Social Welfare and Economic Productivity

This article analyzes Marxian socialist, neo-classical, and Keynesian economic theories toward developing a construct of employment which supports social welfare and economic productivity. It considers their motivational approaches, outcomes, and requirements for social control. A Keynesian construct of employment is recommended as supportive of social well-being, high productivity, and a level of social control reduced from that in currently dominant economic systems. Implications and implementation issues are considered

Sensitivity of tropical seabirds to El Nino precursors

Intense El Niño events severely impact seabird populations, often months in advance of peak temperature anomalies. The trophic mechanisms responsible for these impacts are unknown but are assumed to operate at seasonal scales and to be linked to ocean productivity changes. Precursors to El Niño events include changes in both sea-surface temperature and the depth of the 20°C thermocline. Foraging piscivorous seabirds are known to be sensitive to both thermocline depth and sea-surface temperature change, but the potential influence of these phenomena on breeding dynamics is unknown. Using 18 years of data on three seabirds of the western tropical Pacific, we show that pelagic seabird breeding participation is directly and independently related to changes in both surface chlorophyll concentration and thermocline depth that occur well in advance of El Niño generated sea-surface temperature anomalies. In contrast, breeding in an inshore foraging species is not correlated with any environmental/biological parameters investigated. These findings demonstrate that El Niño related phenomena do not affect seabird prey dynamics solely via productivity shifts at seasonal scales, nor in similar ways across different seabird foraging guilds. Our results also suggest that population declines observed in the western tropical Pacific may be directly related to the frequency and intensity of El Niño anomalies over the study period

Integrating People Experiencing Disabilities into Community Arts Events: Model Project and Guidelines

People experiencing disabilities, and their advocates, are actively demanding the right to live, work, and recreate in integrated and normalized community settings. Community based art education events will be impacted by this in-process civil rights movement. This article focuses on the means through which art educators can make community art events accessible to people experiencing disabilities. Segregated community events, like the Very Special Arts Festivals, are discussed as they are able to accommodate community integration. Guidelines for creating barrier-free environments are included

Plasticity of Noddy Parents and Offspring to Sea-Surface Temperature Anomalies

Behavioral and/or developmental plasticity is crucial for resisting the impacts of environmental stressors. We investigated the plasticity of adult foraging behavior and chick development in an offshore foraging seabird, the black noddy (Anous minutus), during two breeding seasons. The first season had anomalously high sea-surface temperatures and ‘low’ prey availability, while the second was a season of below average sea-surface temperatures and ‘normal’ food availability. During the second season, supplementary feeding of chicks was used to manipulate offspring nutritional status in order to mimic conditions of high prey availability. When sea-surface temperatures were hotter than average, provisioning rates were significantly and negatively impacted at the day-to-day scale. Adults fed chicks during this low-food season smaller meals but at the same rate as chicks in the unfed treatment the following season. Supplementary feeding of chicks during the second season also resulted in delivery of smaller meals by adults, but did not influence feeding rate. Chick begging and parental responses to cessation of food supplementation suggested smaller meals fed to artificially supplemented chicks resulted from a decrease in chick demands associated with satiation, rather than adult behavioral responses to chick condition. During periods of low prey abundance, chicks maintained structural growth while sacrificing body condition and were unable to take advantage of periods of high prey abundance by increasing growth rates. These results suggest that this species expresses limited plasticity in provisioning behavior and offspring development. Consequently, responses to future changes in sea-surface temperature and other environmental variation may be limited

Phenotypic plasticity of nest timing in a post‐glacial landscape: how do reptiles adapt to seasonal time constraints?

Life histories evolve in response to constraints on the time available for growth and development. Nesting date and its plasticity in response to spring temperature may therefore be important components of fitness in oviparous ectotherms near their northern range limit, as reproducing early provides more time for embryos to complete development before winter. We used data collected over several decades to compare air temperature and nest date plasticity in populations of painted turtles and snapping turtles from a relatively warm environment (southeastern Michigan) near the southern extent of the last glacial maximum to a relatively cool environment (central Ontario) near the northern extent of post‐glacial recolonization. For painted turtles, population‐level differences in reaction norm elevation for two phenological traits were consistent with adaptation to time constraints, but no differences in reaction norm slopes were observed. For snapping turtle populations, the difference in reaction norm elevation for a single phenological trait was in the opposite direction of what was expected under adaptation to time constraints, and no difference in reaction norm slope was observed. Finally, among‐individual variation in individual plasticity for nesting date was detected only in the northern population of snapping turtles, suggesting that reaction norms are less canalized in this northern population. Overall, we observed evidence of phenological adaptation, and possibly maladaptation, to time constraints in long‐lived reptiles. Where present, (mal)adaptation occurred by virtue of differences in reaction norm elevation, not reaction norm slope. Glacial history, generation time, and genetic constraint may all play an important role in the evolution of phenological timing and its plasticity in long‐lived reptiles