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At least 1,639 records · Page 91Linked to original sources

Effects of forest management on density, survival, and population growth of wood thrushes

Loss and alteration of breeding habitat have been proposed as causes of declines in several Neotropical migrant bird populations. We conducted a 4-year study to determine the effects of winter prescribed burning and forest thinning on breeding wood thrush ( Hylocichla mustelina ) populations at the Piedmont National Wildlife Refuge (PNWR) in Georgia. We estimated density, adult and juvenile survival rates, and apparent annual survival using transect surveys, radiotelemetry, and mist netting. Burning and thinning did not cause lower densities ( P = 0.25); wood thrush density ranged from 0.15 to 1.30 pairs/10 ha. No radiomarked male wood thrushes ( n = 68) died during the 4 years, but female ( n = 63) weekly survival was 0.981 ± 0.014 (SE) for females ( n = 63) and 0.976 ± 0.010 for juveniles ( n = 38). Apparent annual adult survival was 0.579 (SE = 0.173). Thinning and prescribed burning did not reduce adult or juvenile survival during the breeding season or apparent annual adult survival. Annual population growth (lambda) at PNWR was 1.00 (95% confidence interval = 0.32-1.63), and the considerable uncertainty in this prediction underscores the need for long term monitoring to effectively manage Neotropical migrants. Population growth increased on experimental compartments after the burn and thin (95% CI before = 0.91-0.97, after = 0.98-1.05), while control compartment declined (before = 0.98-1.05, after = 0.87-0.92). We found no evidence that the current management regime at PNWR, designed to improve red-cockaded woodpecker ( Picoides borealis ) habitat, negatively affected wood thrushes.

Georgia↗

Winter use of douglas-fir forests by Blue Grouse in Colorado

We studied winter use of Douglas-fir ( Pseudotsuga menziesii ) forests by blue grouse ( Dendragapus obscurus ) from 1981 to 1983 at 2 study areas in northcentral Colorado. Comparisons of used and available stands indicated grouse were concentrated spatially, but there were no consistent differences related to basal area of tree species, conifer stem densities, and topography that were common to both areas. Blue grouse used dense (2,000 stems/ha) second growth (40-75 yr old), open to dense (200-1,900 stems/ha) mature (100-200 yr old), and open (<100 stems/ha) old-growth (200-600 yr old) stands. Stands used were composed of Douglas-fir alone or in association with subalpine fir ( Abies lasiocarpa ), Engelmann spruce ( Picea engelmannii ), lodgepole pine ( Pinus contorta ), limber pine ( P. flexilis ), Rocky Mountain juniper ( Juniperus scopulorum ), and quaking aspen ( Populus tremuloides ). Grouse used stands on mesic northern and eastern aspects, on xeric southern and western aspects, at elevations of 2,530-2,960 m, and on slopes of 1-45°. Preferential use (P < 0.05) of Douglas-fir trees occurred within stands that had an abundance of limber pine (use = availability) and subalpine fir (use < availability). Large Douglas-fir (20-90 cm dbh) were preferred (P < 0.05) within stands that had an abundance of smaller (≤15 cm dbh) trees. Both sexes used similar trees.

Colorado↗

Research observation: Hydrolyzable and condensed tannins in plants of northwest Spain forests

Tannins are secondary metabolites that may influence feeding by mammals on plants . We analyzed hydrolyzable and condensed tannins in 30 plant species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing in forest ecosystems. Heathers ( Ericaceae ) and plants of the Rose ( Rosaceae ) family had tannins , while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest tannin content of all the species in Rubus sp., with the highest value around 180 mg TAE/g dry weight in spring. Potentilla erecta , Alnus glutinosa and Quercus robur were next with 57 to 44 mg TAE/g dw. Total tannins in heathers ranged from 22 to 36 mg TAE/g dw. Levels of condensed tannins were higher than hydrolyzable for most of the species. Only Betula alba , Calluna vulgaris , Pteridium aquilinum and Vaccinium myrtillus had 100% hydrolyzable tannins . Tannin content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.

northwest Spain↗

Removal and repopulation of breeding birds in a spruce-fir forest community

IN 1949, while engaged in population studies of birds in northern Maine, the authors accumulated considerable information concerning population dynamics of birds inhabiting the Spruce-Fir forest community. This information was obtained in connection with investigations of the effective control by breeding birds of an infestation of the spruce budworm, Choristoneura fumiferana Clem.

The Auk↗

Status of forest birds on Tinian Island, Commonwealth of the Northern Mariana Islands, with an emphasis on the Tinian monarch (Monarcha takatsukasae) (Passeriformes; Monarchidae)

Landbird populations on Tinian Island have been periodically surveyed since 1982 to evaluate the status of non-native and native landbirds. We report the results of surveys in 2013 and the observed changes during 31 years in species population trends based on surveys since 1982. A total of 11 native and 3 non-native species were detected during the 2013 survey. Population sizes were estimated using point-transect distance sampling methods, and population trends were assessed using repeated measures analysis of variance for nine forest bird species. In all years, the Rufous Fantail ( Rhipidura rufifrons ) and Bridled White-eye ( Zosterops conspicillatus ) were the most abundant species, whereas the White-throated Ground Dove ( Pampusana xanthonura ) was the least abundant species in 1982, 1996, and 2008, and the Mariana Kingfisher ( Todiramphus albicilla ) was the least abundant in 2013. The less common species numbered in the low thousands included the Mariana Fruit Dove ( Ptilinopus roseicapilla ), White-throated Ground Dove, introduced Philippine Collared Dove ( Streptopelia dusumieri ), Mariana Kingfisher ( Todiramphus albicilla ), and Micronesian Myzomela ( Myzomela rubratra ). The Micronesian Starling ( Aplonis opaca ) and Tinian Monarch ( Monarcha takatsukasae ) were estimated to number in the tens of thousands. The most abundant species were the Rufous Fantail, numbering more than 100,000, and the Bridled White-eye, numbering more than 400,000. The overall trends in abundance between 1982 and 2013 showed an increase in the Mariana Kingfisher, Micronesian Starling, Rufous Fantail, White-throated Ground Dove, and Philippine Collared Dove, while populations were stable for the Bridled White-eye and Tinian Monarch. Declines were seen for the Mariana Fruit Dove and Micronesian Myzomela. These trends matched previous analyses with the exception that Tinian Monarch abundance showed an increase in the 2013 survey.

Tinian Island↗

A preliminary summary of a seismic-refraction survey in the vicinity of the Tonto Forest Observatory, Arizona

The U.S. Geological Survey complete d a seismic-refraction survey in the vicinity of the Tonto Forest Seismological Observatory (T.F.S.O.) in April and May 1964. More than 1200 km of reversed profiles were surveyed to determine the crustal structure and crustal and upper mantle velocities in this area. The purpose of this work was to provide information on wave-propagation paths of seismic events recorded at T.F.S.O. and to improve the performance of the Observatory in locating and identifying these events. First arrivals indicate that the Mohorovicic discontinuity dips to the northeast by as much as 6 degrees under T.F.S.O., and may even be displaced vertically by as much as 5 km immediately north of the Observatory near the boundary of the Basin and Range and the Colorado Plateau Provinces. A preliminary examination of the first arrivals indicates that the crust at T.F.S.O. is at least 30 km thick and is made up of at least two seismic layers. A thin veneer at the surface with a velocity of approximately 4 km/sec is underlain by a layer with a velocity of approximately 5.9 km/sec to 6.1 km/sec. An intermediate layer with velocity of 6.6 to 7.0 km/sec is probably present in the lower crust, but is not revealed by first arrivals. The velocity of seismic waves in the upper mantle is about 7.9 km/sec.

Arizona↗

Sedimentation in three small forested drainage basins in the Alsea River basin, Oregon

A multidiscipline investigation to determine the effects of logging on the ecology of three small forested tributary basins is a part of an overall study of the Alsea River basin in the Coast Range of Oregon. The investigation of these small basins will be to (1) establish pre-logging conditions, (2) determine the effects of different logging methods, and (3) study the rate of recovery after the timber harvest. This report presents results of sedimentation in the basins, Deer and Flynn Creeks and Needle Branch, for the first 2 years of study (1959 and 1960 water years). Rainfall, runoff, and sediment discharge are seasonal for the Coast Range of western Oregon. About 95 percent of the rainfall and runoff occurs during the period October to May, but nearly 100 percent of the suspended-sediment discharge occurs during the same period. For Deer Creek, in the 1960 water year, 23 percent of the annual suspended-sediment discharge occurred on 1 day, 58 percent during the 10 days of greatest discharge, and 78 percent during the 38 days of greatest discharge. Rainfall is practically equal for all three of the basins. The runoff of the Deer and Flynn Creek basins is about equal, but that of the Needle Branch basin averaged 8 percent less. Sediment yield varies considerably for the three basins. The suspended-sediment yield of the Deer Creek basin is almost twice that of the Needle Branch basin and almost 1? times that of the Flynn Creek basin. Water temperature of the three streams varied only 22?F during the 2 water years. The greatest variation between streams was 3?F in the minimums. Water temperature effect can be neglected in comparing the sediment yields of the basins. The aquifers of the basins have low storage capacities as illustrated by the very low, late summer flow. A study of a midwinter freshet period for the Deer Creek basin showed that virtually all the rainfall left the basin as runoff within 4 days; the period of significant sediment transport was thus very short.

Circular↗

Utilization of humus-rich forest soil (mull) in geochemical exploration for gold

Distribution of gold in humus-rich forest soil (mull) reflects the known distribution of gold deposits in bedrock in the Empire district, Colorado. Gold from the bedrock is accumulated by pine and aspen trees and is concentrated in the mull by the decay of organic litter from the trees. Anomalies in mull which do not coincide with known gold deposits merit further exploration. The gold anomalies in soil (6- to 12-inch depth) and in float pebbles and cobbles poorly reflect the known distribution of gold deposits in bedrock beneath the extensive cover of colluvium and glacial drift.

Circular↗

Data compilation and assessment for water resources in Pennsylvania state forest and park lands

As a result of a cooperative study between the U.S. Geological Survey and the Pennsylvania Department of Conservation and Natural Resources (PaDCNR), available electronic data were compiled for Pennsylvania state lands (state forests and parks) to allow PaDCNR to initially determine if data exist to make an objective evaluation of water resources for specific basins. The data compiled included water-quantity and water-quality data and sample locations for benthic macroinvertebrates within state-owned lands (including a 100-meter buffer around each land parcel) in Pennsylvania. In addition, internet links or contacts for geographic information system coverages pertinent to water-resources studies also were compiled. Water-quantity and water-quality data primarily available through January 2007 were compiled and summarized for site types that included streams, lakes, ground-water wells, springs, and precipitation. Data were categorized relative to 35 watershed boundaries defined by the Pennsylvania Department of Environmental Protection for resource-management purposes. The primary sources of continuous water-quantity data for Pennsylvania state lands were the U.S. Geological Survey (USGS) and the National Weather Service (NWS). The USGS has streamflow data for 93 surface-water sites located in state lands; 38 of these sites have continuous-recording data available. As of January 2007, 22 of these 38 streamflow-gaging stations were active; the majority of active gaging stations have over 40 years of continuous record. The USGS database also contains continuous ground-water elevation data for 32 wells in Pennsylvania state lands, 18 of which were active as of January 2007. Sixty-eight active precipitation stations (primarily from the NWS network) are located in state lands. The four sources of available water-quality data for Pennsylvania state lands were the USGS, U.S. Environmental Protection Agency, Pennsylvania Department of Environmental Protection (PaDEP), and the Susquehanna River Basin Commission. The water-quality data, which were primarily collected after 1970, were summarized by categorizing the analytical data for each site into major groups (for example, trace metals, pesticides, major ions, etc.) for each type (streams, lakes, ground-water wells, and springs) of data compiled. The number of samples and number of detections for each analyte within each group also were summarized. A total of 410 stream sites and 205 ground-water wells in state lands had water-quality data from the available data sets, and these sites were well-distributed across the state. A total of 107 lakes and 47 springs in state lands had water-quality data from the available data sets, but these data types were not well-distributed across the state; the majority of water-quality data for lakes was in the western or eastern sections of the state and water-quality data for springs was primarily located in the central part of the Lower Susquehanna River Valley. The most common types of water-quality data collected were major ions, trace elements, and nutrients. Physical parameters, such as water temperature, stream discharge, or water level, typically were collected for most water-quality samples. Given the large database available from PaDEP for benthic macroinvertebrates, along with some data from other agencies, there is very good distribution of benthic-macroinvertebrate data for state lands. Benthic macroinvertebrate samples were collected at 1,077 locations in state lands from 1973 to 2006. Most (980 samples) of the benthic-macroinvertebrate samples were collected by PaDEP as part of the state assessment of stream conditions required by the Clean Water Act. Data compiled in this report can be used for various water-resource issues, such as basin-wide water-budget analysis, studies of ecological or instream flow, or water-quality assessments. The determination of an annual water budget in selected basins is best supported by the availab

Pennsylvania↗

Influence of forest management on headwater stream amphibians at multiple spatial scales

Background Amphibians are important components of headwater streams in forest ecosystems of the Pacific Northwest (PNW). They comprise the highest vertebrate biomass and density in these systems and are integral to trophic dynamics both as prey and as predators. The most commonly encountered amphibians in PNW headwater streams include the Pacific giant salamander (Dicamptodon tenebrosus), the tailed frog (Ascaphus truei), the southern torrent salamander (Rhyacotriton variegatus), and the Columbia torrent salamander (R. kezeri).

Fact Sheet↗

Ecology and diagnosis of introduced avian malaria in Hawaiian forest birds

Avian malaria is a disease caused by species of protozoan parasites (Plasmodium) that infect birds. Related species commonly infect reptiles, birds and mammals in tropical and temperate regions of the world. Transmitted by mosquitoes, the parasites spend part of their lives in the red blood cells of birds (Figure 1). Avian malaria is common in continental areas, but is absent from the most isolated island archipelagos where mosquitoes do not naturally occur. More than 40 different species of avian Plasmodium have been described, but only one, P. relictum, has been introduced to the Hawaiian Islands. Because they evolved without natural exposure to avian malaria, native Hawaiian honeycreepers are extremely susceptible to this disease. Malaria currently limits the geographic distribution of native species, has population level impacts on survivorship, and is limiting the recovery of threatened and endangered species of forest birds.

Fact Sheet↗

Where is the water? Forest [poster]

Description Water is an integral part of how we interact with the environment and live our everyday lives. This educational poster illustrates where water is in forests, how it moves, and different ways water is used both naturally and through human interaction. This poster is intended for eighth-grade audiences and younger.

General Information Product↗

Geologic map of the eastern part of the Challis National Forest and vicinity, Idaho

The paper version of the Geologic Map of the eastern part of the Challis National Forest and vicinity, Idaho was compiled by Anna Wilson and Betty Skipp in 1994. The geology was compiled on a 1:250,000 scale topographic base map. TechniGraphic System, Inc. of Fort Collins Colorado digitized this map under contract for N.Shock. G.Green edited and prepared the digital version for publication as a GIS database. The digital geologic map database can be queried in many ways to produce a variety of geologic maps.

IMAP↗

Geologic map of the Salmon National Forest and vicinity, east-central Idaho

The geology of the Salmon National Forest, Idaho, was compiled from published and unpublished sources and new field mapping by Evans, Lund, Tysdal, and Winkler between 1997 and 2001. The geology was compiled onto 1:100,000-scale topographic base maps for input into a geographic information system (GIS). The digital geologic map database can be queried in many ways to produce a variety of geologic maps.

IMAP↗

Mineral resource potential of the Baker-Cypress BLM Instant Study Area and Timbered Crater Forest Service Further Planning (RARE II) Areas, Modoc, Shasta, and Siskiyou Counties, California

In accordance with the provisions of the Federal Land Policy and Management Act (Public Law 94-579, October 21, 1976), the Geological Survey and the Bureau of Mines have conducted mineral surveys on certain areas, which formally had been identified as "natural" and "primitive" areas prior to November 1, 1975. The Wilderness Act (Public Law 88-577, September 3, 1964) and related Acts, r equire the Geological Survey and the Bureau of Mines to survey certain areas on Federal lands to determine their mineral resource potential. Results must be made available to the public and be submitted to the Administration and the Congress. These maps and reports present the results of a geological and mineral survey of the Baker-Cypress BLM Instant Study Area and Timbered Crater Forest Service Further Planning (RARE II) areas. The study areas have no potential for metallic commodities as determined from spectrographic analyses of rocks (Peterson, 1980). Several localities within the study areas, however, contain stone that can be used for decorative purposes in building construction . The study areas may also have geothermal potential, but at this time quantitative data are unavailable.

California↗

Geologic and mineral resource potential map of the Chambers Ferry Roadless Area, Sabine National Forest, Sabine County, Texas

Under the provisions of the Wilderness Act (Public Law 88-577, September 3, 1964) and the Joint Conference Report on Senate Bill 4, 88th Congress, the U.S. Geological Survey and the U.S. Bureau of Mines have been conducting mineral surveys of wilderness and primitive areas. Areas officially designated as "wilderness," "wild," or "canoe" when the act was passed were incorporated into the National Wilderness Preservation System, and some of them are presently being studied. The act provided that areas under consideration for wilderness designation should be studied for suitability for incorporation into the Wilderness System. The mineral surveys constitute one aspect of the suitability studies. The act directs that the results of such surveys are to be made available to the public and be submitted to the President and the Congress. This report discusses the results of a mineral survey of the Chambers Ferry Roadless Area, Sabine National Forest, Sabine County, Tex.

Texas↗

Assessment of mineral resource tracts in the Chugach National Forest, Alaska

Locatable minerals have been produced from the Chugach National Forest (CNF) for nearly 100 years. Past gold production has come from the Kenai Peninsula and the Girdwood, Port Wells, and Valdez areas. Copper and by-product gold and silver have been produced from mines at Ellamar, on Latouche Island, and near Valdez. Many of the past-producing properties were not mined out and contain significant inferred reserves of gold, copper, lead, zinc, and silver. This report outlines mineral resource areas (tracts) that contain both identified and undiscovered mineral resources. These tracts were drawn on the basis of one or more of the following criteria: (1) geochemical anomalies, (2) favorable geologic units, (3) presence of mines, prospects or mineral occurrences, and (4) geophysical anomalies. Bliss (1989) used six mineral deposit models to describe the types of deposits known from the CNF. Of these deposit types, only four are sufficiently known and defined in the CNF to be suitable for consideration in outlining and ranking of mineral resource tracts; these deposit types are: (1) Cyprus-type massive sulfide, (2) Chugach-type low-sulfide goldquartz veins, (3) placer gold, and (4) polymetallic vein. The U.S. Bureau of Mines indicated that most of the inferred mineral reserves in the CNF would not be economic to produce under current prices. Small-scale placer gold operations are a possible exception. Other known resources that have recorded past production (oil, coal, rock, sand, and gravel) are not addressed in this report.

Alaska↗

Surface water data and geographic relation to Tertiary age intrusions and hydrothermal alteration in the Grand Mesa, Uncompahgre, and Gunnison National Forests (GMUG) and intervening Bureau of Land Management (BLM) lands

This data set covering the western part of Colorado includes water quality data from eight different sources (points), nine U.S. Geological Survey Digital Raster Graph (DRG) files for topographic bases, a compilation of Tertiary age intrusions (polygons and lines), and two geotiff files showing areas of hydrothermally altered rock. These data were compiled for use with an ongoing mineral resource assessment of theGrand Mesa, Uncompahgre, and Gunnison National Forests (GMUG) and intervening Bureau of Land Management(BLM) lands. This compilation was assembled to give federal land managers a preliminary view of water within sub-basinal areas, and to show possible relationships to Tertiary age intrusion and areas of hydrothermal alteration.

Open-File Report↗