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• 2081. [Article] A capture-recapture analysis of a mountain beaver population in western Oregon

  This report summarizes the results of a field study of a population of the Pacific mountain beaver, Aplodontia rufa pacifica, from August 1965 through August 1967. The study site consisted of a 13. 5- acre ...

  Citation × Citation Citation Abstract Copy Title: A capture-recapture analysis of a mountain beaver population in western Oregon Author: Lovejoy, Bill Pertl This report summarizes the results of a field study of a population of the Pacific mountain beaver, Aplodontia rufa pacifica, from August 1965 through August 1967. The study site consisted of a 13. 5- acre grid on a logged over area in the Coast Range Mountains of Benton County, Oregon. The report also includes new data on the postnatal development, growth, and behavior of two litters of mountain beavers born and raised in captivity. The field study involved the mark-release-and-recapture method using a rotational system of live-trapping on a weekly basis. A total of 5, 144 trap-nights yielded 872 captures of 181 individuals. Of this total, 109 were adult animals and 72 were juveniles Males outnumbered females 61.9 percent to 38. 2 percent. Population estimates were determined by direct enumeration and, ranged from a low of 41 in mid-winter to a high of 54 in July. Densities varied from 2.60 to 3.43 animals per acre. Transients made up a considerable portion of the catch. Longevity records of 5 to 6 years were estimated for wild mountain beavers. Adult males had an average home range size of 0.80 acres, adult females 0.42 acres. The home range of juveniles averaged 0.31 acres. Males made longer forays during the summer months when activity was also at a peak. Overlapping of home ranges was common. Male Aplodontia were in breeding condition throughout January, February, and March. Estrus females were available by about mid- February. Lactating females were observed from 8 April through 27 May. Young Aplodontia are weaned at 6-8 weeks of age and emerge from their burrows the following 2 weeks. The earliest date of capture of a young in the field was 3 June. The growth curve of the young was characterized by a rapid increase during the first 8 weeks, followed by a gradual decline, and eventually reached a plateau in 4 months at 69 percent of the adult weight. Animals were classed as juveniles, yearlings, or adults based on their body weights, character of pelage, and breeding condition. Aging of mountain beavers on the basis of weight alone was considered impossible due to the wide range of size within each age class. The average yearling weighed about 710 g, or 88 percent of the adult mean weight of 806 g. Adult males were consistently heavier than females. The largest male weighed 1130 g; the largest female weighed 1070 g. The body weights of adult Aplodontia were at a seasonal low during their reproductive period in the spring and at a high in mid-summer when food was most abundant. Attempts to breed Aplodontia in captivity were unsuccessful due primarily to the hostile behavior of the females. Title: A capture-recapture analysis of a mountain beaver population in western Oregon Author: Lovejoy, Bill Pertl This report summarizes the results of a field study of a population of the Pacific mountain beaver, Aplodontia rufa pacifica, from August 1965 through August 1967. The study site consisted of a 13. 5- acre grid on a logged over area in the Coast Range Mountains of Benton County, Oregon. The report also includes new data on the postnatal development, growth, and behavior of two litters of mountain beavers born and raised in captivity. The field study involved the mark-release-and-recapture method using a rotational system of live-trapping on a weekly basis. A total of 5, 144 trap-nights yielded 872 captures of 181 individuals. Of this total, 109 were adult animals and 72 were juveniles Males outnumbered females 61.9 percent to 38. 2 percent. Population estimates were determined by direct enumeration and, ranged from a low of 41 in mid-winter to a high of 54 in July. Densities varied from 2.60 to 3.43 animals per acre. Transients made up a considerable portion of the catch. Longevity records of 5 to 6 years were estimated for wild mountain beavers. Adult males had an average home range size of 0.80 acres, adult females 0.42 acres. The home range of juveniles averaged 0.31 acres. Males made longer forays during the summer months when activity was also at a peak. Overlapping of home ranges was common. Male Aplodontia were in breeding condition throughout January, February, and March. Estrus females were available by about mid- February. Lactating females were observed from 8 April through 27 May. Young Aplodontia are weaned at 6-8 weeks of age and emerge from their burrows the following 2 weeks. The earliest date of capture of a young in the field was 3 June. The growth curve of the young was characterized by a rapid increase during the first 8 weeks, followed by a gradual decline, and eventually reached a plateau in 4 months at 69 percent of the adult weight. Animals were classed as juveniles, yearlings, or adults based on their body weights, character of pelage, and breeding condition. Aging of mountain beavers on the basis of weight alone was considered impossible due to the wide range of size within each age class. The average yearling weighed about 710 g, or 88 percent of the adult mean weight of 806 g. Adult males were consistently heavier than females. The largest male weighed 1130 g; the largest female weighed 1070 g. The body weights of adult Aplodontia were at a seasonal low during their reproductive period in the spring and at a high in mid-summer when food was most abundant. Attempts to breed Aplodontia in captivity were unsuccessful due primarily to the hostile behavior of the females. Close

• 2082. [Article] Survey of graduates and undergraduates of North Douglas School District to determine needed improvements in career education

  School systems have an important responsibility to continuously examine and review their educational programs to determine if the programs satisfy the needs of the youth they serve. Systematically collected ...

  Citation × Citation Citation Abstract Copy Title: Survey of graduates and undergraduates of North Douglas School District to determine needed improvements in career education Author: Smith, Richard Alan School systems have an important responsibility to continuously examine and review their educational programs to determine if the programs satisfy the needs of the youth they serve. Systematically collected data derived from former and present students can enable the school system to appraise its effectiveness in fulfilling the aim it has identified and to provide a basis for sound decision making and planning for the future. The purpose of this study was to obtain and analyze graduate and in-school student data that could assist planning toward improvement of the career education program in the North Douglas School District. A total of 317 graduates from North Douglas High School, covering a nine year period from 1962 through 1970, were selected to participate in a follow-up survey through a mailed questionnaire interview. Additionally, 348 in-school students in grades 6-12 of North Douglas School District were selected to participate in an interest survey through the administration of a questionnaire designed to secure information about occupational and educational objectives. The specific criteria on which the study was based were: occupational status, post high school education, income, number of jobs held, location of residence, value of high school training, job satisfaction, high school completion, post high school plans, student training desires, student occupational interest. The following conclusions are based on the findings of this study: (1) The longer students have been out of school the more likely they are to be full-time employed. (2) The longer students have been out of school the more likely they are to be employed in occupations requiring additional training and/or experience. (3) Most post high school education is obtained in a college or university. (4) Additional training and experience contribute significantly to income. (5) A large number of graduates obtain employment outside of Douglas County. (6) English and mathematics are the two most important high school courses for finding and keeping jobs. (7) The majority of in-school students feel that high school completion is important. (8) A need exists for college preparation and occupational training to be an integral part of the curriculum. (9) Students are not receiving adequate guidance and counseling prior to graduation. (10) Students need a marketable skill upon graduation from high school. (11) Post high school training is deemed important in obtaining satisfying employment. Title: Survey of graduates and undergraduates of North Douglas School District to determine needed improvements in career education Author: Smith, Richard Alan School systems have an important responsibility to continuously examine and review their educational programs to determine if the programs satisfy the needs of the youth they serve. Systematically collected data derived from former and present students can enable the school system to appraise its effectiveness in fulfilling the aim it has identified and to provide a basis for sound decision making and planning for the future. The purpose of this study was to obtain and analyze graduate and in-school student data that could assist planning toward improvement of the career education program in the North Douglas School District. A total of 317 graduates from North Douglas High School, covering a nine year period from 1962 through 1970, were selected to participate in a follow-up survey through a mailed questionnaire interview. Additionally, 348 in-school students in grades 6-12 of North Douglas School District were selected to participate in an interest survey through the administration of a questionnaire designed to secure information about occupational and educational objectives. The specific criteria on which the study was based were: occupational status, post high school education, income, number of jobs held, location of residence, value of high school training, job satisfaction, high school completion, post high school plans, student training desires, student occupational interest. The following conclusions are based on the findings of this study: (1) The longer students have been out of school the more likely they are to be full-time employed. (2) The longer students have been out of school the more likely they are to be employed in occupations requiring additional training and/or experience. (3) Most post high school education is obtained in a college or university. (4) Additional training and experience contribute significantly to income. (5) A large number of graduates obtain employment outside of Douglas County. (6) English and mathematics are the two most important high school courses for finding and keeping jobs. (7) The majority of in-school students feel that high school completion is important. (8) A need exists for college preparation and occupational training to be an integral part of the curriculum. (9) Students are not receiving adequate guidance and counseling prior to graduation. (10) Students need a marketable skill upon graduation from high school. (11) Post high school training is deemed important in obtaining satisfying employment. Close

• 2083. [Article] The influence of soil fumigants and soil fungicides on some important soil-borne plant pathogens

  Twelve chemicals (Busan 72, Chloropicrin, Dacthal, Dexon, Duter, EP 161, Lanstan, Methyl bromide, Phaltan, Vapam, Vidden D, Vorlex) were tested to determine their effect on populations of certain important ...

  Citation × Citation Citation Abstract Copy Title: The influence of soil fumigants and soil fungicides on some important soil-borne plant pathogens Author: Liu, Marlene Mei-yu Twelve chemicals (Busan 72, Chloropicrin, Dacthal, Dexon, Duter, EP 161, Lanstan, Methyl bromide, Phaltan, Vapam, Vidden D, Vorlex) were tested to determine their effect on populations of certain important soil-borne microorganisms including the onion pink root fungus Pyrenochaeta terrestris. The soil used was from a field in Malheur County, Oregon that was known to be heavily infested with P. terrestris. Fumigants were added to the soil in glass jars which were immediately sealed with plastic electrician's tape. Fungicides and the herbicide were added to soil in polyethylene bags and were mixed very thoroughly with the soil. These experiments were done entirely in the laboratories and greenhouse at the Oregon State University Campus in Corvallis. The fumigants (Chloropicrin, EP 161, Lanstan, Methyl bromide, Vapam, Vidden D, Vorlex) were more effective than the fungicides (Busan 72, Dexon, Duter, Phaltan) in reducing the number of viable propagules of all of the fungi studied. In these tests the herbicide Dacthal was relatively ineffective against any of the microorganisms. EP 161, Methyl bromide and Vorlex gave best control of Pythium spp. (mostly P. ultimum) and the rate of recovery in soils treated with these fumigants were slow. The fungicide Dexon usually reported to be highly toxic to P. ultimum did not control this fungus in these tests. Chloropicrin, Methyl bromide, Vapam and Vorlex were most effective against Fusarium spp. (mostly F. roseum and F. oxysporum). Chloropicrin permanently inactivated most of the actinomycetes and recovery of this group of microorganisms was very slow in soils treated with either Chloropicrin or Methyl bromide. In soils treated with Vapam or Vorlex, on the other hand, populations of actinomycetes became much greater than in the untreated soil. The heavily sporulating, carbohydrates reducing fungi were almost completely eliminated by Chloropicrin, Methyl bromide and Vorlex. EP 161, and Vapam were almost as effective but Lanstan and Vidden D were ineffective. Penicillium spp. were encountered with greatest frequency, following by Mortierella, Mucor, Alternaria, Rhizopus, Trichoderma, Aspergillus, Cephalosporium, Stephyllium, Epicoccum, Chaetorniurn, Sclerotinia and Monilia in that order. EP 161, Methyl bromide and Vapam were most effective against Pyrenochaeta terrestris and the rate of recovery in soils treated with these materials was very slow. Chloropicrin, Vapam and Vorlex were almost as effective, while Lanstan and Vidden D were relatively ineffective. Title: The influence of soil fumigants and soil fungicides on some important soil-borne plant pathogens Author: Liu, Marlene Mei-yu Twelve chemicals (Busan 72, Chloropicrin, Dacthal, Dexon, Duter, EP 161, Lanstan, Methyl bromide, Phaltan, Vapam, Vidden D, Vorlex) were tested to determine their effect on populations of certain important soil-borne microorganisms including the onion pink root fungus Pyrenochaeta terrestris. The soil used was from a field in Malheur County, Oregon that was known to be heavily infested with P. terrestris. Fumigants were added to the soil in glass jars which were immediately sealed with plastic electrician's tape. Fungicides and the herbicide were added to soil in polyethylene bags and were mixed very thoroughly with the soil. These experiments were done entirely in the laboratories and greenhouse at the Oregon State University Campus in Corvallis. The fumigants (Chloropicrin, EP 161, Lanstan, Methyl bromide, Vapam, Vidden D, Vorlex) were more effective than the fungicides (Busan 72, Dexon, Duter, Phaltan) in reducing the number of viable propagules of all of the fungi studied. In these tests the herbicide Dacthal was relatively ineffective against any of the microorganisms. EP 161, Methyl bromide and Vorlex gave best control of Pythium spp. (mostly P. ultimum) and the rate of recovery in soils treated with these fumigants were slow. The fungicide Dexon usually reported to be highly toxic to P. ultimum did not control this fungus in these tests. Chloropicrin, Methyl bromide, Vapam and Vorlex were most effective against Fusarium spp. (mostly F. roseum and F. oxysporum). Chloropicrin permanently inactivated most of the actinomycetes and recovery of this group of microorganisms was very slow in soils treated with either Chloropicrin or Methyl bromide. In soils treated with Vapam or Vorlex, on the other hand, populations of actinomycetes became much greater than in the untreated soil. The heavily sporulating, carbohydrates reducing fungi were almost completely eliminated by Chloropicrin, Methyl bromide and Vorlex. EP 161, and Vapam were almost as effective but Lanstan and Vidden D were ineffective. Penicillium spp. were encountered with greatest frequency, following by Mortierella, Mucor, Alternaria, Rhizopus, Trichoderma, Aspergillus, Cephalosporium, Stephyllium, Epicoccum, Chaetorniurn, Sclerotinia and Monilia in that order. EP 161, Methyl bromide and Vapam were most effective against Pyrenochaeta terrestris and the rate of recovery in soils treated with these materials was very slow. Chloropicrin, Vapam and Vorlex were almost as effective, while Lanstan and Vidden D were relatively ineffective. Close

• 2084. [Article] Life history and production studies of Sialis californica Banks and Sialis rotunda Banks (Megaloptera : Sialidae)

  Comparative ecological studies of Sialis californica Banks and Sialis rotunda Banks were made in Western Oregon from 1966 to 1968. Field collections for S. rotunda were made in fish holding pond at the Oak ...

  Citation × Citation Citation Abstract Copy Title: Life history and production studies of Sialis californica Banks and Sialis rotunda Banks (Megaloptera : Sialidae) Author: Azam, Khaja Mohammed Comparative ecological studies of Sialis californica Banks and Sialis rotunda Banks were made in Western Oregon from 1966 to 1968. Field collections for S. rotunda were made in fish holding pond at the Oak Creek laboratories, 5 miles west of Corvallis, Benton County, and for S. californica in enriched sections of Berry Creek experimental stream, 13 miles north of Corvallis. Life histories were determined in aquaria, in laboratory streams and the natural habitats. S. rotunda, predominantly a pond species, completed its life cycle in one year in all situations. S. californica, commonly a stream species, took one or two years depending on oviposition time and food availability. Both species were reared successfully in the laboratory through all stages of their life cycle. There are ten larval instars. The larvae are carnivorous and feed on insects and other small benthic organisms. Biweekly or monthly samples were collected from the two locations for density, biomass, growth rate and production studies. Density and biomass of S. rotunda in the pond were much higher than for S. californica in the stream. Enrichment with sucrose and urea resulted in differences in density and biomass of S. californica between the four experimental sections at Berry Creek. The unenriched section usually had a high density but low or similar biomass compared with the enriched sections which had few individuals. The lower density in the enriched sections was associated with unfavorable substrate conditions for early-instar larvae because of dense mats of the filamentous bacterium, Sphaerotilus natans. Larger larvae were not hindered by the S. natans filaments and had rapid growth because food was abundant. Production of both species was calculated by two methods: (1) Ricker's (1946) method, the product of growth rate and mean biomass; and (2) Allen's (1951) graphical method, using numbers per m² and mean individual weight at each sampling date, The results from both methods were comparable, with the graphical method usually providing a slightly higher estimate of production. Annual production of S. rotunda in the pond was 13.18 Kilocalories/ m². This was more than double the production of S. californica in any of the sections of Berry Creek. In Berry Creek, the population in the unenriched section had low growth rate but the density of larvae resulted in high biomass and a comparable production to that in the enriched sections. The accumulated annual production was: unenriched, 4.94 Kilocalories; enriched, 6, 34 Kilocalories. The relationship between larval growth and food consumption rate was established by experiments in laboratory streams during summer and winter. These data were used to estimate food consumption by field populations. In the pond, S. rotunda larvae consumed 137 gms/m²/year. In Berry Creek, individuals in enriched sections consumed one and half to two times more food than did individuals in the unenriched section. Title: Life history and production studies of Sialis californica Banks and Sialis rotunda Banks (Megaloptera : Sialidae) Author: Azam, Khaja Mohammed Comparative ecological studies of Sialis californica Banks and Sialis rotunda Banks were made in Western Oregon from 1966 to 1968. Field collections for S. rotunda were made in fish holding pond at the Oak Creek laboratories, 5 miles west of Corvallis, Benton County, and for S. californica in enriched sections of Berry Creek experimental stream, 13 miles north of Corvallis. Life histories were determined in aquaria, in laboratory streams and the natural habitats. S. rotunda, predominantly a pond species, completed its life cycle in one year in all situations. S. californica, commonly a stream species, took one or two years depending on oviposition time and food availability. Both species were reared successfully in the laboratory through all stages of their life cycle. There are ten larval instars. The larvae are carnivorous and feed on insects and other small benthic organisms. Biweekly or monthly samples were collected from the two locations for density, biomass, growth rate and production studies. Density and biomass of S. rotunda in the pond were much higher than for S. californica in the stream. Enrichment with sucrose and urea resulted in differences in density and biomass of S. californica between the four experimental sections at Berry Creek. The unenriched section usually had a high density but low or similar biomass compared with the enriched sections which had few individuals. The lower density in the enriched sections was associated with unfavorable substrate conditions for early-instar larvae because of dense mats of the filamentous bacterium, Sphaerotilus natans. Larger larvae were not hindered by the S. natans filaments and had rapid growth because food was abundant. Production of both species was calculated by two methods: (1) Ricker's (1946) method, the product of growth rate and mean biomass; and (2) Allen's (1951) graphical method, using numbers per m² and mean individual weight at each sampling date, The results from both methods were comparable, with the graphical method usually providing a slightly higher estimate of production. Annual production of S. rotunda in the pond was 13.18 Kilocalories/ m². This was more than double the production of S. californica in any of the sections of Berry Creek. In Berry Creek, the population in the unenriched section had low growth rate but the density of larvae resulted in high biomass and a comparable production to that in the enriched sections. The accumulated annual production was: unenriched, 4.94 Kilocalories; enriched, 6, 34 Kilocalories. The relationship between larval growth and food consumption rate was established by experiments in laboratory streams during summer and winter. These data were used to estimate food consumption by field populations. In the pond, S. rotunda larvae consumed 137 gms/m²/year. In Berry Creek, individuals in enriched sections consumed one and half to two times more food than did individuals in the unenriched section. Close

• 2085. [Article] The effects of logging on periphyton communities of coastal streams

  The purpose of this study was to investigate the effects of logging on the productivity, structure and biomass of a periphyton community developed in mountain streams. The three streams used in this investigation ...

  Citation × Citation Citation Abstract Copy Title: The effects of logging on periphyton communities of coastal streams Author: Hansmann, Eugene W. (Eugene William), 1933- The purpose of this study was to investigate the effects of logging on the productivity, structure and biomass of a periphyton community developed in mountain streams. The three streams used in this investigation were located in the coast range of Lincoln County, Oregon. They were selected for similarity of habitat, terrestrial canopy, and benthic community, one dominated by diatoms (Bacillarophyceae). In 1966, Deer Creek watershed was subjected to a selective pattern of logging with a buffer strip of canopy left standing along the stream. Needle Branch watershed was subjected to clearcut logging resulting in the removal of all the canopy, and the watershed of Flynn Creek was left in its natural condition and used as a control. Clearcut logging had a profound impact on the aquatic environment of Needle Branch. As indicated by light reading taken during primary productivity runs, the stream received a mean value of seven times more light in 1967, July-September, as compared to similar months in 1964, prior to logging. This resulted in a high of 50 langleys/hr as compared to 13 langleys/hr recorded prior to logging. Concurrently, the mean temperature of the stream, as measured during productivity runs, increased 6 C, with a high of 26 C recorded as compared to 14. 8 C prior to logging. The impact of these environmental changes resulted in a periphyton community quite different from that existing in the stream prior to logging. As indicated by the communities developed on glass artificial substrates, this stream, which supported a periphyton community of diatoms prior to logging, was changed to a habitat supporting a mixed community of filamentous algae and diatoms with the filamentous algae becoming dominant. The diatom flora of the stream changed in species composition and became more uniform throughout, after logging. Samples of the communities taken from the natural substrate and glass artificial substrates were similar, but dissimilarities arose in the relative abundance of the species. Artificial substrates cut from native rock supported a community of greater similarity to that on the natural substrate, than existed between the communities developed on glass artificial substrates and the natural substrate. The index of the autotrophic organisms in Needle Branch (mg chlorophyll a/m²) was lower after logging, as compared to that found in the stream prior to logging. Mean concentrations,for cornparable months, of 51.3 mg chlorophyll a/m² were recorded before logging, compared to 9.10 mg chlorophyll a/m² recorded after logging. The index of the autotrophic organisms obtained from the organic matter collected on glass artificial substrates showed little relationship to that obtained from the substrate of the stream. Respiration of the community after logging was higher than during the equivalent period prior to logging. Mean respiration for July-September, 1964,was 1.08 g 0₂/m²/day while after logging the reduced biomass had a respiration rate of 1.28 g 0₂ /m²/day. After logging, gross primary production was higher in Needle Branch than in Flynn Creek (control watershed),, but slightly less than recorded for Needle Branch prior to logging. Needle Branch maintained gross primary production comparable to the prelogging period, with a smaller biomass, by increased efficiency of photosynthesis per mg chlorophyll a. The photosynthesis-respiration ratio (P/R ratio) indicated that prior to logging, Needle Branch was autotrophic for all seasons except the fall. After logging, the stream became progressively more heterotrophic from spring to summer. Title: The effects of logging on periphyton communities of coastal streams Author: Hansmann, Eugene W. (Eugene William), 1933- The purpose of this study was to investigate the effects of logging on the productivity, structure and biomass of a periphyton community developed in mountain streams. The three streams used in this investigation were located in the coast range of Lincoln County, Oregon. They were selected for similarity of habitat, terrestrial canopy, and benthic community, one dominated by diatoms (Bacillarophyceae). In 1966, Deer Creek watershed was subjected to a selective pattern of logging with a buffer strip of canopy left standing along the stream. Needle Branch watershed was subjected to clearcut logging resulting in the removal of all the canopy, and the watershed of Flynn Creek was left in its natural condition and used as a control. Clearcut logging had a profound impact on the aquatic environment of Needle Branch. As indicated by light reading taken during primary productivity runs, the stream received a mean value of seven times more light in 1967, July-September, as compared to similar months in 1964, prior to logging. This resulted in a high of 50 langleys/hr as compared to 13 langleys/hr recorded prior to logging. Concurrently, the mean temperature of the stream, as measured during productivity runs, increased 6 C, with a high of 26 C recorded as compared to 14. 8 C prior to logging. The impact of these environmental changes resulted in a periphyton community quite different from that existing in the stream prior to logging. As indicated by the communities developed on glass artificial substrates, this stream, which supported a periphyton community of diatoms prior to logging, was changed to a habitat supporting a mixed community of filamentous algae and diatoms with the filamentous algae becoming dominant. The diatom flora of the stream changed in species composition and became more uniform throughout, after logging. Samples of the communities taken from the natural substrate and glass artificial substrates were similar, but dissimilarities arose in the relative abundance of the species. Artificial substrates cut from native rock supported a community of greater similarity to that on the natural substrate, than existed between the communities developed on glass artificial substrates and the natural substrate. The index of the autotrophic organisms in Needle Branch (mg chlorophyll a/m²) was lower after logging, as compared to that found in the stream prior to logging. Mean concentrations,for cornparable months, of 51.3 mg chlorophyll a/m² were recorded before logging, compared to 9.10 mg chlorophyll a/m² recorded after logging. The index of the autotrophic organisms obtained from the organic matter collected on glass artificial substrates showed little relationship to that obtained from the substrate of the stream. Respiration of the community after logging was higher than during the equivalent period prior to logging. Mean respiration for July-September, 1964,was 1.08 g 0₂/m²/day while after logging the reduced biomass had a respiration rate of 1.28 g 0₂ /m²/day. After logging, gross primary production was higher in Needle Branch than in Flynn Creek (control watershed),, but slightly less than recorded for Needle Branch prior to logging. Needle Branch maintained gross primary production comparable to the prelogging period, with a smaller biomass, by increased efficiency of photosynthesis per mg chlorophyll a. The photosynthesis-respiration ratio (P/R ratio) indicated that prior to logging, Needle Branch was autotrophic for all seasons except the fall. After logging, the stream became progressively more heterotrophic from spring to summer. Close

• 2086. [Article] The thermal regulation, microclimate, and distribution of the mountain beaver, Aplodontia rufa pacifica Merriam

  An investigation was undertaken to determine the role that temperature might play in limiting the distribution of the mountain beaver, Aplodontia rufa. A field study was carried on from August, 1965, through ...

  Citation × Citation Citation Abstract Copy Title: The thermal regulation, microclimate, and distribution of the mountain beaver, Aplodontia rufa pacifica Merriam Author: Johnson, Sheldon Robert An investigation was undertaken to determine the role that temperature might play in limiting the distribution of the mountain beaver, Aplodontia rufa. A field study was carried on from August, 1965, through August, 1966, in the coast mountains of Benton County, Oregon, and consisted of measuring the annual temperature cycle of the burrows in conjunction with air temperatures taken at a height of six cm above the soil surface. A laboratory study was conducted to determine the effects of ambient temperature on body temperature, metabolic rate, thermal conductance, insensible water loss, and heart rate. The burrow system was characterized by a cool and stable microclimate. The temperature above the soil showed a maximum annual fluctuation of 40.5°C, the temperature within the burrows varied 18.3°C, with a weekly variation in burrow temperature of not more than 4°C. Annual range in mean burrow temperature was from 2° to 14°C. The mean body temperature of Aplodontia, over an ambient temperature range of from 4° to 290°C was 37.60°C. Free-living animals had a mean body temperature of 38.0°C. Hyperthermia began at ambient temperatures above 29°C and a lethal body temperature of approximately 42°C was reached after a two hour exposure to temperatures between 32° and 35°C. Aplodontia lacked a thermoneutral zone and minimal metabolic rates were recorded at high ambient temperatures when the animals were hyperthermic. Under conditions of heat stress, mean metabolicrateswere 65 percent of the values predicted by Kleiber's equation. These animals were lethargic, their respiration rates decreased to as low as 18 per minute with minimal heart rates between 60 and 100 beats per minute. The mean minimal recorded heart rates, based on body weight, were 38 percent of that predicted. Aplodontia had a minimal thermal conductance of 0.195 cal/g/hr/°C which could only be increased by a factor of 1.84. Winter animals had an effective insulation L. 23 times that of summer animals. This raised the lower critical temperature of summer animals by 4°C (19° to 23°C). Aplodontia required a six degree thermal gradient to dissipate its minimal heat production. Insensible water loss could only be increased by a factor of 2.3 over the ambient temperature range of 12° to 31.5°C. At the latter ambient temperature, evaporative heat loss accounted for only 22 percent of Aplodontia's total heat loss. The results of this investigation indicated that high environmental temperatures may act as an important limiting factor in the distribution of the mountain beaver which lacks adequate mechanisms to avoid heat stress. Title: The thermal regulation, microclimate, and distribution of the mountain beaver, Aplodontia rufa pacifica Merriam Author: Johnson, Sheldon Robert An investigation was undertaken to determine the role that temperature might play in limiting the distribution of the mountain beaver, Aplodontia rufa. A field study was carried on from August, 1965, through August, 1966, in the coast mountains of Benton County, Oregon, and consisted of measuring the annual temperature cycle of the burrows in conjunction with air temperatures taken at a height of six cm above the soil surface. A laboratory study was conducted to determine the effects of ambient temperature on body temperature, metabolic rate, thermal conductance, insensible water loss, and heart rate. The burrow system was characterized by a cool and stable microclimate. The temperature above the soil showed a maximum annual fluctuation of 40.5°C, the temperature within the burrows varied 18.3°C, with a weekly variation in burrow temperature of not more than 4°C. Annual range in mean burrow temperature was from 2° to 14°C. The mean body temperature of Aplodontia, over an ambient temperature range of from 4° to 290°C was 37.60°C. Free-living animals had a mean body temperature of 38.0°C. Hyperthermia began at ambient temperatures above 29°C and a lethal body temperature of approximately 42°C was reached after a two hour exposure to temperatures between 32° and 35°C. Aplodontia lacked a thermoneutral zone and minimal metabolic rates were recorded at high ambient temperatures when the animals were hyperthermic. Under conditions of heat stress, mean metabolicrateswere 65 percent of the values predicted by Kleiber's equation. These animals were lethargic, their respiration rates decreased to as low as 18 per minute with minimal heart rates between 60 and 100 beats per minute. The mean minimal recorded heart rates, based on body weight, were 38 percent of that predicted. Aplodontia had a minimal thermal conductance of 0.195 cal/g/hr/°C which could only be increased by a factor of 1.84. Winter animals had an effective insulation L. 23 times that of summer animals. This raised the lower critical temperature of summer animals by 4°C (19° to 23°C). Aplodontia required a six degree thermal gradient to dissipate its minimal heat production. Insensible water loss could only be increased by a factor of 2.3 over the ambient temperature range of 12° to 31.5°C. At the latter ambient temperature, evaporative heat loss accounted for only 22 percent of Aplodontia's total heat loss. The results of this investigation indicated that high environmental temperatures may act as an important limiting factor in the distribution of the mountain beaver which lacks adequate mechanisms to avoid heat stress. Close

• 2087. [Article] Geology of the North Muddy Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona

  The North Muddy Mountains are located in southern Nevada, about 65 km northeast of Las Vegas and near the eastern boundary of the Basin and Range province. The north-south-trending range block is bounded ...

  Citation × Citation Citation Abstract Copy Title: Geology of the North Muddy Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona Author: Carpenter, Daniel G. The North Muddy Mountains are located in southern Nevada, about 65 km northeast of Las Vegas and near the eastern boundary of the Basin and Range province. The north-south-trending range block is bounded on the east and west, respectively, by east- and west-dipping, high-angle normal faults. Sevier age contractional and Cenozoic age extensional structures are present in the range. The Summit thrust and Willow Tank thrust crop out, respectively, on the southwest and northeast sides of the North Muddy Mountains. A newly mapped thrust segment connects the Summit and Willow Tank thrusts. It juxtaposed Jurassic on Cretaceous age rocks. The most recent displacement on the thrust is bracketed between 95.8 +/- 3.5 Ma (age of youngest deformed rocks) and 93.1 +/- 3.4 Ma (age of oldest overlying undeformed beds). These numbers indicate an Albian to Turonian(?) age range for the thrust. The Summit-Willow Tank thrust sheet was later folded by a northwest-southeast-trending, southwest inclined fold train by displacement on the Arrowhead fault, a Miocene and possibly younger(?) extensional structure. The oldest (Albian) synorogenic deposits in the area contain exotic clasts of formations that were not involved in local thrusting; the debris was transported eastward from older thrust sheets. Younger (Cenomanian) synorogenic beds are composed of Mesozoic age clasts at the base of the section, grading to early paleozoic age clasts near the top (reverse clast stratigraphy). This succession represents progressively deeper erosion of thrust sheets during thrusting. The younger synorogenic beds do not contain exotic clasts from older, more westerly, thrust sheets. This observation suggests that local thrust sheets formed highlands that shut off the westerly source provenance. Rotation of horst and graben blocks on Cenozoic normal and oblique-slip faults caused dismembering of older Sevierage fold-thrust structures, and in some cases refolded them into new orientations. Seismic reflection sections show wedge-shaped sedimentary beds, indicating that range-bounding normal faults formed half-grabens. The normal faults appear to be listric impling that the net slip on these faults is a measure of the regional horizontal extension. Title: Geology of the North Muddy Mountains, Clark County, Nevada and regional structural synthesis : fold-thrust and basin-range structure in southern Nevada, southwest Utah, and northwest Arizona Author: Carpenter, Daniel G. The North Muddy Mountains are located in southern Nevada, about 65 km northeast of Las Vegas and near the eastern boundary of the Basin and Range province. The north-south-trending range block is bounded on the east and west, respectively, by east- and west-dipping, high-angle normal faults. Sevier age contractional and Cenozoic age extensional structures are present in the range. The Summit thrust and Willow Tank thrust crop out, respectively, on the southwest and northeast sides of the North Muddy Mountains. A newly mapped thrust segment connects the Summit and Willow Tank thrusts. It juxtaposed Jurassic on Cretaceous age rocks. The most recent displacement on the thrust is bracketed between 95.8 +/- 3.5 Ma (age of youngest deformed rocks) and 93.1 +/- 3.4 Ma (age of oldest overlying undeformed beds). These numbers indicate an Albian to Turonian(?) age range for the thrust. The Summit-Willow Tank thrust sheet was later folded by a northwest-southeast-trending, southwest inclined fold train by displacement on the Arrowhead fault, a Miocene and possibly younger(?) extensional structure. The oldest (Albian) synorogenic deposits in the area contain exotic clasts of formations that were not involved in local thrusting; the debris was transported eastward from older thrust sheets. Younger (Cenomanian) synorogenic beds are composed of Mesozoic age clasts at the base of the section, grading to early paleozoic age clasts near the top (reverse clast stratigraphy). This succession represents progressively deeper erosion of thrust sheets during thrusting. The younger synorogenic beds do not contain exotic clasts from older, more westerly, thrust sheets. This observation suggests that local thrust sheets formed highlands that shut off the westerly source provenance. Rotation of horst and graben blocks on Cenozoic normal and oblique-slip faults caused dismembering of older Sevierage fold-thrust structures, and in some cases refolded them into new orientations. Seismic reflection sections show wedge-shaped sedimentary beds, indicating that range-bounding normal faults formed half-grabens. The normal faults appear to be listric impling that the net slip on these faults is a measure of the regional horizontal extension. Close

• 2088. [Article] A food web analysis of a Mojave Desert geothermal spring system and feeding ecology of Moapa dace (Moapa coriacea)

  Understanding food webs is fundamental in conserving endangered species and maintaining healthy ecosystem function, particularly in desert spring systems. We identified dominant energy sources in the ...

  Citation × Citation Citation Abstract Copy Title: A food web analysis of a Mojave Desert geothermal spring system and feeding ecology of Moapa dace (Moapa coriacea) Author: St Saviour, Adam Understanding food webs is fundamental in conserving endangered species and maintaining healthy ecosystem function, particularly in desert spring systems. We identified dominant energy sources in the Muddy River Warm Springs area, Clark County, NV using carbon and nitrogen natural abundance stable isotope analyses. We examined isotopic signatures of specific macroinvertebrate food resources for the endangered, drift-feeding Moapa dace (Moapa coriacea) and looked for changes in isotopic ratios over the stream gradient. Our results indicate the Muddy River Warm Springs area is supported primarily by allochthonous energy sources, and Moapa dace did not focus on specific macroinvertebrate taxa. We characterized a pattern of downstream δ¹³C enrichment, which is seemingly common in groundwater-fed systems but discussed very little in the literature. We conclude that ground water carbon of marine origin, heterotrophic respiration, and fractionation and depletion of the δ¹³C pool by autotrophs contribute to a wide range δ¹³C values in primary producers and to the downstream enrichment pattern in the Muddy River Warm Springs. We then quantified macroinvertebrate drift throughout the Moapa dace's current and historic range within the Muddy River Warm Springs. We examined the relationship of total drift biomass and temperature and associations between specific macroinvertebrate orders and Moapa dace abundance. We also explored habitat characteristics associated with Moapa dace and their prey. In 2008 and 2009, total drift biomass/time and the biomass of most orders was negatively correlated with temperature and positively correlated with discharge. Only Lepidoptera and Neotaenioglossa had positive associations with temperature in 2008. In 2009, total biomass/volume had a negative linear relationship with temperature and a positive linear relationship with discharge, though these relationships were absent in 2008. Moapa dace were associated with high temperatures, low stream discharge, shallow depth, and low drift biomass both years. They were positively associated with thermally tolerant Lepidoptera and Neotaenioglossa in 2008 and no orders in 2009. Macroinvertebrate drift may be greater in cooler, downstream reaches because temperatures in those reaches are favorable to more taxa, there is more cumulative benthic area contributing to production, and there are fewer drift feeding insectivores. Lastly, we examined Moapa dace feeding flexibility by experimentally manipulating drift (0, 34, 64, 100, and 200% of the natural drift level) and quantified their feeding attempts and success. We found that Moapa dace are obligate drift feeders, selecting drift 40 times more frequently than benthos. They did not adaptively shift foraging modes from drift to benthic when drift was experimentally reduced. Drift feeding rate increased in response to increasing drift, but drift feeding success only increased from the 0% to the 64% drift level and did not change in the 100% and 200% levels. No relationship between fish size or food availability and aggression was detected. Moapa dace may share an interspecific foraging association with sympatric White River springfish (Crenichthys baileyi). Moapa dace are currently excluded from lower, more productive reaches by invasive species and fish barriers. Maintaining spring flows, eradicating non-natives, and restoring system connectivity will likely benefit Moapa dace and other Muddy River Warm Springs endemics. Title: A food web analysis of a Mojave Desert geothermal spring system and feeding ecology of Moapa dace (Moapa coriacea) Author: St Saviour, Adam Understanding food webs is fundamental in conserving endangered species and maintaining healthy ecosystem function, particularly in desert spring systems. We identified dominant energy sources in the Muddy River Warm Springs area, Clark County, NV using carbon and nitrogen natural abundance stable isotope analyses. We examined isotopic signatures of specific macroinvertebrate food resources for the endangered, drift-feeding Moapa dace (Moapa coriacea) and looked for changes in isotopic ratios over the stream gradient. Our results indicate the Muddy River Warm Springs area is supported primarily by allochthonous energy sources, and Moapa dace did not focus on specific macroinvertebrate taxa. We characterized a pattern of downstream δ¹³C enrichment, which is seemingly common in groundwater-fed systems but discussed very little in the literature. We conclude that ground water carbon of marine origin, heterotrophic respiration, and fractionation and depletion of the δ¹³C pool by autotrophs contribute to a wide range δ¹³C values in primary producers and to the downstream enrichment pattern in the Muddy River Warm Springs. We then quantified macroinvertebrate drift throughout the Moapa dace's current and historic range within the Muddy River Warm Springs. We examined the relationship of total drift biomass and temperature and associations between specific macroinvertebrate orders and Moapa dace abundance. We also explored habitat characteristics associated with Moapa dace and their prey. In 2008 and 2009, total drift biomass/time and the biomass of most orders was negatively correlated with temperature and positively correlated with discharge. Only Lepidoptera and Neotaenioglossa had positive associations with temperature in 2008. In 2009, total biomass/volume had a negative linear relationship with temperature and a positive linear relationship with discharge, though these relationships were absent in 2008. Moapa dace were associated with high temperatures, low stream discharge, shallow depth, and low drift biomass both years. They were positively associated with thermally tolerant Lepidoptera and Neotaenioglossa in 2008 and no orders in 2009. Macroinvertebrate drift may be greater in cooler, downstream reaches because temperatures in those reaches are favorable to more taxa, there is more cumulative benthic area contributing to production, and there are fewer drift feeding insectivores. Lastly, we examined Moapa dace feeding flexibility by experimentally manipulating drift (0, 34, 64, 100, and 200% of the natural drift level) and quantified their feeding attempts and success. We found that Moapa dace are obligate drift feeders, selecting drift 40 times more frequently than benthos. They did not adaptively shift foraging modes from drift to benthic when drift was experimentally reduced. Drift feeding rate increased in response to increasing drift, but drift feeding success only increased from the 0% to the 64% drift level and did not change in the 100% and 200% levels. No relationship between fish size or food availability and aggression was detected. Moapa dace may share an interspecific foraging association with sympatric White River springfish (Crenichthys baileyi). Moapa dace are currently excluded from lower, more productive reaches by invasive species and fish barriers. Maintaining spring flows, eradicating non-natives, and restoring system connectivity will likely benefit Moapa dace and other Muddy River Warm Springs endemics. Close

• 2089. [Article] Becoming more Latino : the journey of an extension nutrition education program

  Latinos are the fastest growing minority group in the U.S. and are expected to be 25% of the population by the year 2050. Latinos also are more vulnerable and at higher risk for poor health outcomes including ...

  Citation × Citation Citation Abstract Copy Title: Becoming more Latino : the journey of an extension nutrition education program Author: Hernandez, Rebecca Latinos are the fastest growing minority group in the U.S. and are expected to be 25% of the population by the year 2050. Latinos also are more vulnerable and at higher risk for poor health outcomes including diabetes and other chronic health ailments than Anglos. Many of the serious effects of these diseases can be ameliorated with changes in diet and life style. These changes are difficult for ethnic minority populations who lack access to culturally sensitive health and nutrition education. Several innovative and culturally competent programs have been initiated to provide preventative health education to high risk Latinos. Las Comidas Latinas (The Spanish Meals) was developed to teach health and food safety to Latino families as part of a federally funded education program for low income, Food Stamp eligible families. The ecological model was utilized to examine the microsystem, mesosystems, exosystem, and macrosystem processes and changes that underlie the development and implementation of a culturally competent program. What characterized the relationships between and among program staff, other agency partners, and participants? And what organizational processes contributed to the development and success of this culturally competent program? Interviews with participants, staff members at the state, county, supervisory and direct service levels and partner agencies indicated that participants in Las Comidas Latinas reported warm and caring relationships that contributed to positive health and social gains for themselves and their children. Organizational factors at the macro, intermediate, and individual levels such as a positive view of diversity, environmental and political factors, policy changes, and involvement of Latino community leaders contributed to successful program development and implementation. Two major categories of recommendations have emerged for the field and other service programs: attending to cultural norms and enacting flexible organizational policies. Key findings in cultural relevance include: create a bilingual and bicultural workforce, promote a safe and welcoming environment, hire program paraprofessionals for their cultural knowledge, and seek information about the community to be served. Organizational recommendations are to persist in approaching the target community to be served, provide "space" for innovation, and recognize and value unexpected social benefits. Future research suggestions are included. Title: Becoming more Latino : the journey of an extension nutrition education program Author: Hernandez, Rebecca Latinos are the fastest growing minority group in the U.S. and are expected to be 25% of the population by the year 2050. Latinos also are more vulnerable and at higher risk for poor health outcomes including diabetes and other chronic health ailments than Anglos. Many of the serious effects of these diseases can be ameliorated with changes in diet and life style. These changes are difficult for ethnic minority populations who lack access to culturally sensitive health and nutrition education. Several innovative and culturally competent programs have been initiated to provide preventative health education to high risk Latinos. Las Comidas Latinas (The Spanish Meals) was developed to teach health and food safety to Latino families as part of a federally funded education program for low income, Food Stamp eligible families. The ecological model was utilized to examine the microsystem, mesosystems, exosystem, and macrosystem processes and changes that underlie the development and implementation of a culturally competent program. What characterized the relationships between and among program staff, other agency partners, and participants? And what organizational processes contributed to the development and success of this culturally competent program? Interviews with participants, staff members at the state, county, supervisory and direct service levels and partner agencies indicated that participants in Las Comidas Latinas reported warm and caring relationships that contributed to positive health and social gains for themselves and their children. Organizational factors at the macro, intermediate, and individual levels such as a positive view of diversity, environmental and political factors, policy changes, and involvement of Latino community leaders contributed to successful program development and implementation. Two major categories of recommendations have emerged for the field and other service programs: attending to cultural norms and enacting flexible organizational policies. Key findings in cultural relevance include: create a bilingual and bicultural workforce, promote a safe and welcoming environment, hire program paraprofessionals for their cultural knowledge, and seek information about the community to be served. Organizational recommendations are to persist in approaching the target community to be served, provide "space" for innovation, and recognize and value unexpected social benefits. Future research suggestions are included. Close

• 2090. [Article] The effect of race on the knowledge and use of health services among rural elderly

  This study was unique in that it focused on the rural elderly of both Black and White ethnicity's, explored differences between groups by comparing use and knowledge of health services, and controlled ...

  Citation × Citation Citation Abstract Copy Title: The effect of race on the knowledge and use of health services among rural elderly Author: Bodison, Chantelle This study was unique in that it focused on the rural elderly of both Black and White ethnicity's, explored differences between groups by comparing use and knowledge of health services, and controlled for gender, income, educational attainment, health status, age, and health beliefs - the independent variables of the study. Knowledge and use of health services were dependent factors. The Anderson behavioral model (Anderson, 1995) has been extensively used to examine health service utilization. It conceptualizes health care use as the outcome of a complex pattern of interactions between predisposing, enabling, and need-for care characteristics. The literature has supported the utility of the behavioral model for assessing the health care practices of rural older adults. Four questions were posed. These were translated into hypotheses for statistical testing purposes. Black and White elderly residents of one rural county in South Carolina comprised the target population. A sample of 150 elderly residents, 75 Black and 75 White, were randomly selected for participation. The multidimensional health locus of control scales were modified and used in the test instrument to assess health beliefs (both internal and external). Descriptive and background data were gathered from administration of the survey. Data were analyzed using SPSS statistical software. Analysis of variance (ANOVA) and the LSD (least significant differences) test, in addition to regression analysis, were used to compute and identify differences between and among groups of data. This research concluded that there was no correlation between use of services and knowledge of facilities. There were differences in utilization by race, with Whites making greater use of health care facilities. Educational levels, health status, income, household composition, type of insurance, and age influenced health care use. It was not influenced by gender, distance from facilities, and health beliefs. There was a statistically significant difference between knowledge and race, with Blacks having higher knowledge scores. Gender, health status, income, distance from facilities, and health beliefs did not influence knowledge. However, educational attainment, type of insurance, household composition, and age did. Service use and knowledge were adequate, in contrast to findings in the literature. Recommendations for further study were formulated. Title: The effect of race on the knowledge and use of health services among rural elderly Author: Bodison, Chantelle This study was unique in that it focused on the rural elderly of both Black and White ethnicity's, explored differences between groups by comparing use and knowledge of health services, and controlled for gender, income, educational attainment, health status, age, and health beliefs - the independent variables of the study. Knowledge and use of health services were dependent factors. The Anderson behavioral model (Anderson, 1995) has been extensively used to examine health service utilization. It conceptualizes health care use as the outcome of a complex pattern of interactions between predisposing, enabling, and need-for care characteristics. The literature has supported the utility of the behavioral model for assessing the health care practices of rural older adults. Four questions were posed. These were translated into hypotheses for statistical testing purposes. Black and White elderly residents of one rural county in South Carolina comprised the target population. A sample of 150 elderly residents, 75 Black and 75 White, were randomly selected for participation. The multidimensional health locus of control scales were modified and used in the test instrument to assess health beliefs (both internal and external). Descriptive and background data were gathered from administration of the survey. Data were analyzed using SPSS statistical software. Analysis of variance (ANOVA) and the LSD (least significant differences) test, in addition to regression analysis, were used to compute and identify differences between and among groups of data. This research concluded that there was no correlation between use of services and knowledge of facilities. There were differences in utilization by race, with Whites making greater use of health care facilities. Educational levels, health status, income, household composition, type of insurance, and age influenced health care use. It was not influenced by gender, distance from facilities, and health beliefs. There was a statistically significant difference between knowledge and race, with Blacks having higher knowledge scores. Gender, health status, income, distance from facilities, and health beliefs did not influence knowledge. However, educational attainment, type of insurance, household composition, and age did. Service use and knowledge were adequate, in contrast to findings in the literature. Recommendations for further study were formulated. Close