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Research about Canada, United States

Source-linked reports with geographic coverage including Canada, United States.

At least 1,243 records · Page 69Linked to original sources
USGS1984

Avian cholera in the central and Mississippi flyways 1979-80

Waterfowl mortality from avian cholera during July 1979-May 1980 was widespread in the Central and Mississippi flyways, occurring in a wide variety of species and locations from nesting grounds of snow geese ( Chen caerulescens ) on Hudson Bay south to waterfowl wintering areas on the Texas coast and playa lakes region. Mortality estimates at the various sites ranged from several birds to over 72,000. The chronological and geographic occurrence of outbreaks corresponded closely to waterfowl migrations from infected sites, suggesting that waterfowl served to distribute avian cholera along migration routes. Recurrent outbreaks at several locations suggest that these sites have become enzootic for this disease. The magnitude of avian cholera mortality and its geographic spread during 1979-80 underscores the need to address management of this disease on an intra- and inter-flyway basis.

Central & Mississippi flyways↗
USGS1984

Renal coccidiosis in interior Canada geese, Branta canadensis interior Todd, of the Mississippi Valley population

Kidneys from 309 Interior Canada geese from three locations in the Mississippi Flyway were examined for renal coccidia. Oocysts and/or young zygotes of Eimeria sp. were found in 6.8% of goose kidneys sampled. Only one type of renal coccidian oocyst was observed. Significantly more immature geese were infected than adults; however, there was no significant difference observed between the prevalences of infection in male and female birds. A host cellular response to zygotes and oocysts was noted in the majority of infected adult geese. Heavily infected kidneys were hypertrophic with minute foci on the surface of the organ. Histological examinations showed large numbers of unsporulated oocysts accumulated in distended collecting tubules, resulting in pressure necrosis to adjacent tissue and urate retention. Zygotes were observed in the cytoplasm of tubule cells and extracellularly in interstitial tissue. Infected tubule cells were characterized by the peripheral location of the nuclei, cytoplasmic basophilia, and cellular hypertrophy. This is the first report of an Eimeria sp. in the kidneys of Canada geese of the Mississippi Valley population.

Illinois, Ontario, Wisconsin↗
USGS1984

Red fox predation on breeding ducks in midcontinent North America

Red fox ( Vulpes vulpes ) predation on nesting ducks was assessed by examining 1,857 adult duck remains found at 1,432 fox rearing dens from 1968 to 1973. Dabbling ducks were much more vulnerable to foxes than diving ducks. Dabbling ducks (1,798) found at dens consisted of 27% blue-winged teals ( Anas discors ), 23% mallards ( A. platyrhynchos ), 20% northern pintails (A. acuta), 9% northern shovelers ( Spatula clypeata ), 8% gadwalls ( A. strepera ), 3% green-winged teals ( A. crecca ), 2% American wigeons ( A. americana ), and 10% unidentified. Relative abundance of individual species and nesting chronology were the most important factors affecting composition of ducks taken by foxes. Seventy-six percent of 1,376 adult dabbling ducks and 40% of 30 adult diving ducks for which sex was determined were hens. In western North Dakota and western South Dakota, 65% of mallard and northern pintail remains found at dens were hens compared with 76% in eastern North Dakota and eastern South Dakota ( P < 0.05). Percentage hens varied among the 5 most common dabbling ducks found at dens. In eastern North Dakota and eastern South Dakota, where predation on ducks was greatest, an average of 64% of gadwall, 73% of northern pintail, 81% of blue-winged teal, 81% of mallard, and 90% of northern shoveler remains found at dens were hens. Percentage hens among duck remains found at dens increased as the duck nesting season progressed. Numbers of adult ducks found at individual dens ranged from 0 to 67. The average number of ducks found in and around den entrances was used as an index of fox predation rates on ducks. Predation rate indices ranged from 0.01 duck/den in Iowa to 1.80 ducks/den in eastern North Dakota. Average annual predation rate indices for dabbling ducks in a 3-county intensive study area in eastern North Dakota were closely correlated with May pond numbers ( r = 0.874, P < 0.10) and duck population size ( r = 0.930, P < 0.05), but all species were not affected in the same manner or to the same degree. Drought had least effect on populations and predation rate indices of mallards and gadwalls and had greatest effect on those of northern pintails and northern shovelers. Hens of early nesting species were more vulnerable to foxes than hens of late nesting species. Predation rate indices were expanded to estimate total numbers of ducks taken by fox families during the denning season. Estimated numbers of dabbling ducks taken annually by individual fox families in 2 physiographic regions comprising the intensive study area ranged from 16.1 to 65.9. Predation was highest during wet years and lowest during dry years and averaged lower, but was more variable, in the region where tillage was greatest and wetland water levels were least stable. Predation in the intensive study area averaged 2.97 adult dabbling ducks/ km 2 /year and represented an estimated average annual loss of 13.5% of hen and 4.5% of drake populations in that area. Of 5,402 individual food items found at dens in the intensive study area, 24% were adult ducks. Ducks made up an estimated maximum average of 16% of the prey biomass required by fox families during the denning season. The average annual take of adult ducks by foxes in the midcontinent area was estimated to be about 900,000. This estimate included both scavenged and fox-killed ducks, as well as ducks taken after the denning season. Fox impact on midcontinent ducks was greatest in eastern North Dakota where both fox and duck densities were relatively high. Predation in that area was likely increased by environmental factors, especially intensive agriculture that concentrated nesting and reduced prey abundance. Predation by red foxes and other predators severely reduces duck production in the midcontinent area. Effective management to increase waterfowl production will necessitate coping with or reducing high levels of predation.

Iowa, Manitoba, Minnesota, Nebraska, North Dakota,↗
USGS1982

Fission-track ages of late Cenozoic distal tephra beds in the Yukon Territory and Alaska

Six distal tephra beds from the Yukon Territory and Alaska have been dated by the fission-track method. Zircon and glass ages were determined for the Fort Selkirk and Lost Chicken tephra beds, but only glass ages for the others.Assuming that no track fading has occurred in the glass, Old Crow and Dawson tephra beds are younger than 120 000 and 52 000 years BP, respectively. Mosquito Gulch tephra is 1.22 Ma old, Fort Selkirk tephra is about 1 Ma old, the Ester Ash Bed is 0.45 Ma old, and the best estimate of the age of Lost Chicken tephra is the range 1.7–2.6 Ma.It is evident from these results and from the known abundance of tephra beds within late Cenozoic deposits of the Yukon Territory and Alaska that application of the fission-track method to distal tephra, in conjunction with detailed characterization studies, offers great potential for elucidation of the late Cenozoic geologic history of Alaska and the Yukon Territory.

Alaska, Yukon Territory↗
USGS1982

A workshop on raptor management and biology in Alaska and western Canada - A summary

A workshop on raptor management and biology in Alaska and western Canada was held on February 20, 1981, in Anchorage, Alaska. It was attended by about 50 biologists. The following twofold prime objective was established: (1) To prevent any raptor species from becoming extirpated in any significant part of its present range; and (2) to establish or maintain population levels consistent with the carrying capacity of available habitat. Collateral objectives, specific priorities, potential threats, and research and management needs were discussed, and the ideas that were expressed were listed. Although a draft raptor program was not developed during the workshop, the information and opinions presented by the participants will form a strong foundation and set a correct course for its subsequent formation.

Alaska↗
USGS1982

Geothermal systems of the Cascade Range

In the central and southern Cascade Range, plate convergence is oblique, and Quaternary volcanism produces mostly basalt and mafic andesite; large andesite-dacite composite volcanoes and silicic dome fields occur in restricted areas of long-lived igneous activity. To the north, plate convergence is normal, producing widely spaced centers in which mafic lavas are minor. Most Cascade volcanoes are short-lived and unlikely to be underlain at shallow levels by large magma bodies that could support high-temperature geothermal systems. Such systems are known, however, near Meager Mountain, at Newberry Volcano, and near Lassen Peak. Persistent fumaroles occur on several major composite volcanoes, but drilling to date has been insufficient to determine whether exploitable geothermal reservoirs occur at depth. Thermal springs away from the major volcanic centers are few and generally inconspicuous. However, significant geothermal systems along and west of the Cascade Range may well be masked by abundant cold ground water.

California, Oregon, Washington↗
USGS1982

A study of gizzard nematodes and renal coccidiosis in Canada geese (Branta canadensis interior) of the Mississippi Valley population

A total of 309 Mississippi Valley Population Canada geese, Branta canadensis interior , of different sex and age groups was collected from three locations in the Mississippi Flyway from 1979-1981 and examined for gizzard nematodes and renal coccidia. Three species of nematodes were removed from the gizzards, Amidostomum anseris, A. spatulatum, and Epomidiostomum crami. The latter two species are reported from this population of geese for the first time. Gizzard nematodes were found in 95.2% of all Canada geese examined, with A. anseris being the most abundant of the three species. There was no statistically significant difference between immatures and adults in the abundance of total nematodes species however, immature geese carried significantly more A. anseris and adult geese harbored significantly more A. spatulatum and E. crami infections. No significant difference in gizzard worm infections between male and female birds was observed. The abundance of overall gizzard nematodes was greatest in Canada geese from Winisk, Ontario (11.9), but the abundance of worms in southern Illinois geese (10.0) was similar. Geese from Horicon National Wildlife Refuge had the lowest abundance of infection, 7.5. The overall abundance of nematodes showed a general increase the second year of the study in each sex and age group and at each collection area. Each of three species of nematodes was responsible for some degree of damage to the gizzard lining and koilin, but E. crami was the most pathogenic of the species recovered. The occurrence of renal coccidiosis in Canada geese of this flyway is reported for the first time; the etiologic agent is Eimeria clarkei. The oocysts and/or endogenous stages of E. clarkei were present in 6.8% of the Canada geese sampled and this was the only species found. Male and female geese showed no significant differences in E. clarkei infections, however, significantly more immature geese than adult geese were infected with this species. A cell mediated response to the presence of E. clarkei oocysts and endogenous stages was seen in 83.3% of infected adult geese, but only 20% of immature geese showed a macrophage response to the infective stages of this parasite. A massive E. clarkei infection caused the death of one goose collected at Horicon National Wildlife Refuge. Amidostomiasis, epomidiostomiasis, and renal coccidiosis were important pathogenic diseases in the Mississippi Valley Population Canada geese but did not directly cause significant mortality in the population.

Illinois, Ontario, Wisconsin↗
USGS1981

Range extension of pink salmon (Oncorhynchus Gorbuscha) into the lower Great Lakes

In 1979, pink salmon (Oncorhynchus gorbuscha) completed expansion of their range from Lake Superior into each of the other four Great Lakes. Record numbers of pink salmon were observed during the 1979 spawning migrations into Lake Superior tributaries. Although the species was introduced into Lake Superior 24 years ago, movement into the other lakes was slow and until 1979 the known range was restricted to northern portions of Lakes Michigan and Huron. Pink salmon remain the only self-sustaining species of salmon in the Great Lakes. The development of spawning populations in both even- and odd-numbered years and other adaptive biological features may have contributed to their success.

Great Lakes, Lake Erie, Lake Ontario↗
USGS1981

River basins of the United States: the Columbia

This leaflet, one of a series on the river basins of the United States, contains information on the Columbia River Basin, including a brief early history, a description of the physical characteristics, and other statistical data. At present, other river basins included in the series are The Colorado, The Delaware, The Hudson, The Potomac, and The Wabash.

British Columbia, Idaho, Montana, Nevada, Oregon, ↗
USGS1981

Proceedings of the Symposium on Mineral Deposits of the Pacific Northwest: Geological Society of America, Cordilleran Section meeting at Corvallis, Oregon, March 20-21, 1980

Stratiform and volcanogenic zinc-lead-barium deposits occur within the pelagic Kagvik sequence in the Red Dog Creek and Drenchwater Creek areas in the DeLong Mountains and Howard Pass quadrangles. The sulfide deposits occur together with barite, tuff, sandstone, shale, chert, and keratophyre flows and sills. The three main occurrences of the stratiform zinc-lead-barium deposits in the Red Dog Creek area are: (1) thinly-bedded stratiform sulfide minerals in organic-rich Mississippian shale and chert; (2) massive sulfide vein and breccia fillings in Mississippian shale; and (3) massive stratiform barite lenses and nodules in chert and shale of the Siksikpuk Formation. The Drenchwater Creek area has only the first type. Sulfide-bearing zones of up to several thousand meters long occur in both areas with up to 19.5 percent Zn, 9.5 percent Pb, and locally more than 150 ppm Ag. Radiolaria from sulfide-bearing chert indicate in the Red Dog Creek area a Mississippian age of sulfide deposition. K/Ar ages of 319 + 10 m.y. and 330 + 17 m.y. obtained from biotite in keratophyre associated with sulfide-bearing tuff and chert in the Drenchwater Creek area indicate a Mississippian age of sulfide deposition. Sulfur isotope analyses of sulfur-bearing minerals from the Red Dog Creek area indicate that a combination of sea water sulfate and deep-seated sulfur was probably the source of the barite sulfate whereas sulfur in the sulfide minerals may have had a deep-seated source. Sulfur isotope values for sphalerite and galena are similar in vein and stratiform occurrences. Using sulfur isotope geothermetry, spalerite-galena pairs yield paleotemperatures of between 115° and 305° C. Lead isotope analyses of galena from both the Red Dog Creek and Drenchwater Creek areas yield Triassic model ages of approximately 200 m.y. Lead isotope data from both areas approximate typical orogene, i.e., Andean-type arc, or mature island-arc values and exclude ocean floor rifting for the generation of lead. The isotopic, petrologic, and field data indicate the stratiform zinc-lead-barium deposits in the Red Dog Creek and Drenchwater Creek areas formed during a short-lived period of Mississippian submarine volcanism in either an incipient Andean-type arc, or mature island arc environment.

Alaska, British Columbia, California↗
USGS1981

Single-channel seismic-reflection profiles and sidescan-sonar records collected on Georges Bank

Subbottom seismic-reflection, echo-sounding, and sidescan-sonar records were collected by the U.S. Geological Survey during two cruises over Georges Bank aboard the R/V OCEANUS (cruise 056, March 6-15, 1979 and cruise 067, August 6-13, 1979) (fig. 1). The data collected during these two cruises contributed to a study of bed-form types and distribution and of sediment transport paths on Georges Bank. The equipment used on these cruises consisted of an EG&G Uniboom 12-kHz echo-sounder, and Klein sidescan-sonar system. The Uniboom data were collected on the OCEANUS 067 cruise along 185 km of trackline (fig. 1), and the 12-kHz echo-sounder and sidescan-sonar data were collected during both cruises along 465 km of trackline. Navigation during both cruises consisted of Loran-C fixes logged at least every 15 minutes. After the cruise, the navigation data were digitized and stored on magnetic tape. The original records can be studied at the U.S. Geological Survey Data Library at Woods Hole, MA 02543. Microfilm copies of the subbottom, echo-sounding, and sidescan-sonar records can be purchased only from the National Geophysical and Solar-Terrestrial Data Center, NOAA/EDIS/NGSDC, Code D621, 325 Broadway, Boulder, CO 80303 (303-497-6338).

Georges Bank↗
USGS1980

Semidiurnal bottom pressure and tidal currents on Georges Bank and in the Mid-Atlantic Bight

Observations of the semidiurnal (M 2 ) tidal current, bottom pressure, and coastal sea level from Nova Scotia to Cape May, New Jersey) show that: 1) the surface pressure at the edge of the Continental Shelf in the study area has a relatively uniform amplitude (40 cm) and phase (12 hr Greenwich); 2) in the Mid-Atlantic Bight, the semidiurnal M 2 tide is co-oscillating, and the onshore M 2 tidal current reaches a maximum 2 approximately 90° or 3.1 hr before high water; 3) in the Georges Bank region of the shelf, the M tide is more progressive than it is in the 2 Mid-Atlantic Bight, and the onshore M 2 tidal current in the Georges Bank 2 region of the shelf reaches a maximum about 7 ° or 14 min before high water; 4) the strongest M 2 tidal currents observed in the study area are 2 near the crest of Georges Bank (typical amplitudes are 74 cm/s near the surface); 5) the M 2 tidal currents are weaker in the Mid-Atlantic Bight 2 (typical amplitudes are 16 cm/s near the surface) than on Georges Bank; and 6) the tidal currents are weakest near the bottom south of Cape Cod in a region of transition between progressive and co-oscillating tides.

Georges Bank, Mid-Atlantic Bight↗
USGS1980

Organochlorine and heavy metal residues in black duck eggs from the Atlantic Flyway, 1978

Black duck ( Anas rubripes ) eggs were collected during 1978 in the Atlantic Flyway. One egg from each of 49 clutches was analyzed for organochlorine compounds and mercury. DDE was detected in 39 eggs, ranging from 0.09 ppm to 3.4 ppm, wet weight. DDE residues were highest in eggs from Delaware, where the mean DDE level was 2.0 ppm. DDT and TDE were present at Iow levels in only five and four eggs, respectively. PCBs resembling Aroclor 1260 were detected in 24 eggs and ranged from 0.43 ppm to 2.9 ppm. Eggs from Massachusetts and Rhode Island contained an average of >1.0 ppm PCBs, but eggs from Nova Scotia, Pennsylvania, Maryland, and Virginia contained no detectable PCBs. Dieldrin, oxychlordane, and heptachlor epoxide were present in a few samples at low levels. Mercury was detected in 31 eggs, ranging from 0.07 ppm to 0.34 ppm, wet weight. Twenty eggs analyzed for chromium, copper, and arsenic contained averages of 0.64 ppm, 1.7 ppm, and 0.18 ppm, respectively. No geographic pattern was observed in these metal residue levels. Eggshell thickness (0.347 mm) was identical to the pre-1946 norm.

Delaware, Maine, Maryland, Massachusetts, New Brun↗