Firehole River Research Articles

Effects of Thermal Additions from the Yellowstone Geyser Basins on the Bacteriology of the Firehole River

A series of stations was established on the Firehole River where it flows through the main geyser basins of Yellowstone Park, and temperature, pH, alkalinity, conductivity, and phosphate were measured. The temperature of the water gradually increased as it flowed through the thermal area, at its warmest averaging about 16°C higher than in the cool area (10° to 26°C). Alkalinity, conductivity, pH, and phosphate also increased markedly. The growth rates of periphtic bacteria measured in situ on glass slides were virtually identical at different stations despite the wide differences in temperature. The effect of temperature on the incorporation of 14C—glucose by benthic bacteria populations at the different stations demonstrated that the temperature optimum for this process increased in parallel with the temperature of the habitat. It is thus concluded that the bacteria are near—optimally adapted to the temperature of their habitat and that despite wide differences in temperature the rate of bacterial activity is the same. In another study, samples of water were placed on agar media and incubated at temperatures of 25°, 55°, and 70°C to obtain estimates of the number of bacteria able to grow at these temperatures. The thermophilic organisms developing at 55°C were primarily Bacillus stearothermophilus at those at 70°C primarily Thermus aquaticus. Thermophiles were not present in water which had not received thermal additions, but both kinds of thermophiles were found in the warm water, and numbers increased progressively as more thermal water entered. In the recovery zone downstream from the thermally region, the numbers of thermophilic bacteria decreased markedly. The possible value of these thermophilic bacteria as indicators of thermal pollutions is discussed. It is suggested that the Firehole River is an excellent model for long—term studies on the ecological consequences of thermal pollution.

Distribution of riffle insects of the Firehole River, Wyoming

The Firehole River flows through the major hot spring basins of Yellowstone National Park. The runoff water from the hot springs changes the physical and chemical characteristics of the river as evidenced by the progressive downstream increase in temperature and pH. Nine sampling stations were located in riffles above and below all the major influxes of hot spring water into the river. One hundred thirty-five samples of bottom organisms were collected from all the stations from July through October 1952 and in May 1953. The organisms were identified, counted and weighed. Four other streams in Yellowstone National Park were surveyed to gather more information about the factors influencing the ecological distribution of the stream insects. Arctopsyche, Rhyacophila, Micrasema, Ephemerella glacialis, E. grandis, E. doddsi, Rhithrogena, Libellula, Baetis tricaudatus, E. flavilinea, E. heterocaudata, Ironopsis, Iron, Chimarra, Acroneuria and the Tendepedidae were considered to be forms that preferred colder water. Leptocella, Ophiogomphus, Argia, Paraleptophlebia, Tricorythodes, Helicopsyche, Oecetis, Hydropsyche, Brachycentrus, Atherix, Antocha and E. euterpe were considered to be forms that preferred warmer water. Glossosoma, Agraylea, Narpus, Pteronarcys and the Simuliidae were widely distributed and did not evidence any temperature preference. The nature of the substrate and rate of water flow were discussed in addition to temperature as factors influencing the ecological distribution of stream insects. The seasonal fluctuations in average numbers of twenty-three species or genera were described. Although the data do not permit a direct contribution to the study of the community concept, they do indicate that the species occur along a continuously fluctuating environment and that discrete communities cannot be described.

Ecology of the Riffle Insects of the Firehole River, Wyoming

I NTRODUCTION Most of the early work in stream biology was concerned with qualitative studies. Some studies have emphasized adaptations of stream organisms to their environment (Pearse 1939, Muttkowski 1939); others have considered community structure (Allee and Schmidt 1951) or stream zonation (Macan and Worthington 1951). Several biologists made faunal and zoogeographic studies (Behning 1929, Berg 1948, Thienemann 1950). Most quantitative studies were made considering the bottom fauna as fish food and have mainly been surveys to attempt to evaluate the pounds per acre of fish food available. While working as a ranger naturalist in Yellowstone National Park, I became curious as to the effect waters from hot springs would have on the fauna of the Firehole River. My interest in quantitative ecology was stimulated because the Firehole River appeared to offer the opportunity of studying rapidly changing environmental conditions and their effect on the qualitative and quantitative composition of fauna. This research was made possible by a National Science Foundation fellowship which enabled the author to spend several months in the field in early spring and late fall. A grant from the Gans Fund, Bethany College, W. Va., helped defray some of the expenses involved in the field operations. The author owes a great debt to the National Park Service and to the personnel of Yellowstone National Park for their cooperation in establishing this study and for providing facilities during the late fall and early spring. Special thanks are due to Park Naturalist David de L. Condon for his efforts in making the study possible and for his continued cooperation and aid whenever needed. Dr. Gerard A. Rohlich and Dr. Gerald W. Lawton of the College of Engineering of the University of Wisconsin performed a valuable service in analyzing water from the Firehole River. Dr. Robert W. Pennak, University of Colorado, gave advice and help in making some of the identifications. I wish to thank Dr. Arthur D. Hasler, under whose direction this work was done, for his critical evaluation of the work in progress and for the generous use of his time. This paper is based on parts of a thesis submitted in partial fulfillment of the requirements of the Ph.D. degree at the University of Wisconsin.