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Naturalization of the flood regime in regulated rivers the case of the upper Mississippi River
No abstract available.
Flooding to restore connectivity of regulated, large-river wetlands: Natural and controlled flooding as complementary processes along the lower Missouri River
You can always count on finding the Mississippi just where you left it last year. But the Missouri is a tawny, restless, brawling flood. It cuts corners, runs around at night, fills itself with snags and traveling sandbars, lunches on levees, and swallows islands and small villages for dessert. Its perpetual dissatisfaction with its bed is the greatest peculiarity of the Missouri.… It makes farming as fascinating as gambling. You never know whether you are going to harvest corn or catfish (Fitch 1907, p. 637).
[Book review] Keeping all the Pieces. Perspectives on Natural History and the Environment, by W. Gibbons
No abstract available.
Naturally occurring and experimentally induced castor bean (Ricinus communis) poisoning in ducks
Castor bean ( Ricinus communis ) poisoning accounted for the death of several thousand ducks in the Texas panhandle in the fall and winter months of 1969-1971. Signs of intoxication resembled those of botulism, except for mucoid, blood-tinged excreta. The most common lesions were severe fatty change in the liver, widely distributed internal petechial hemorrhages or ecchymoses, and catarrhal enteritis. Nearly intact castor beans were found in the stomach of one duck during field necropsy. Fragments of seed coat resembling castor bean were found in the stomachs of 10 of 14 ducks examined in the laboratory. Clinical signs and postmortem lesions observed in wild ducks were induced experimentally in mallards ( Anas platyrhynchos ) by force-feeding intact castor beans. Toxicity titrations were erratic, but the LD50 appeared to be between three and four seeds. The mouse toxicity test, used to detect Clostridium botulinum toxin in the blood serum of intoxicated ducks, was negative in every case. Hemagglutination and precipitin tests generally failed to detect castor bean in extracts of excreta or intestinal contents of experimentally intoxicated ducks.
Nature of firm expectations in petroleum exploration
Recent interest in the state of the United States domestic petroleum industry has resulted in an increased concern regarding the ability of current large- scale econometric models to provide useful predictions about supply price sensitivity and about the effects of differing policy options on future supply. The petroleum industry's exploration and reserve response functions appear to have eluded traditional modeling approaches. Properties of firm exploration behavior are obscured when highly aggregated data are used. Data pertaining to different geographical areas are frequently combined using dummy variables to denote characteristics peculiar to a region. In these models price tends to be more related to the quality of the crude oil than to incremental costs of exploration and development of individual deposits. The effect of price changes on expected supplies is clearly moderated by the level of resource depletion for a particular basin. A major obstacle to carrying out a less aggregated analysis has been the lack of data on specific basins, but another obstacle has been the belief that field behavior is too erratic to model successful.
Natural cavities used by wood ducks in north-central Minnesota
Radio telemetry was used to locate 31 wood duck ( Aix sponsa ) nest cavity sites in 16 forest stands. Stands were of 2 types: (1) mature (mean = 107 years) northern hardwoods (10 nest sites), and (2) mature (mean = 68 years) quaking aspen ( Populus tremuloides ) (21 nest sites). Aspen was the most important cavity-producing tree used by wood ducks and accounted for 57 percent of 28 cavities inspected. In stands used by wood ducks, the average density of suitable cavities was about 4 per hectare. Trees containing nests were closer to water areas (P < 0.05) and the nearest forest canopy openings (P < 0.01) than was a random sample of trees from the same stands. A significant (P < 0.005) relationship existed between the orientation of the cavity entrance and the nearest canopy opening. Potential wood duck cavities usually were clustered within a stand rather than randomly distributed. Selection of trees by woodpeckers for nest hole construction probably influenced the availability of cavities used by wood ducks. A plan for managing forests to benefit wood ducks and other wildlife dependent on old-growth timber is discussed.
Use of solicited bands and separation of hunting and natural mortality: a comment
We previously presented (Conroy 1985, Conroy et al. 1989) models for analysis of band recovery data stratified into those voluntarily reported and those obtained by solicitation, similar to models described by Pollock et al. (1994). We discuss differences between the 2 modeling approaches and suggest designs and analyses involving overlapping samples of standard and reward bands to enable adjustment for temporal and geographic variation in reporting and solicitation rates,
[Book review] Ospreys: A natural and unnatural history
The Osprey ( Pandion haliaetus ) is now arguably the world's best known bird of prey. The DDT-related Osprey population crash in the northeastern United States resulted in an unparalleled amount of research during the last 20 years. In 1969, when I published my first paper on Ospreys in The Auk, there were only three or four osprey papers of consequence in the United States, plus an important paper on Swedish Ospreys, which hardly compares to the nearly 300 papers (the great majority dealing with Ospreys) cited by Poole in his book. Based on his detailed investigations in eastern North America and the literature from throughout the world, Poole wrote a book with perfect timing. A synthesis of the massive literature on this species was needed, and judging from the bio- logical soundness, completeness, and clear writing style, Poole was the proper person to write the book. Of course it is one aim to prepare a synthesis but, in addition, Poole carefully points out potential biases in data, gaps in information, and needs for further research. The book is both informative, and points out research problems for the next generation of Osprey investigators.
[Book review] The Ancient Murrelet. A natural history in the Queen Charlotte Islands
Leadership in ecological research on north-temperate-zone seabirds has long been associated with the region of the northeastern Atlantic, which enjoys a tradition of detailed, innovative work spanning several decades. Although the temperate North Pacific is home to several of the same species that figure prominently in the Atlantic and also has a host of interesting species found nowhere else, Pacific birds had until recently received comparatively little attention. Few important advances in seabird biology had come from the northern North Pacific, which tended to leave those of us who work in the region harboring a slight inferiority complex. Happily, this situation is beginning to change. First, we are learning that in some instances the population dynamics of shared species differ greatly between the North Pacific and North Atlantic. The Pacific work, therefore, is more than just a rehash of that which was already known. It takes an important step toward understanding geographic variation in demography – variation that would not have been anticipated from any casual comparison of the environments, which appear superficially similar. Second, we are starting to see the results of in-depth work on species unique to the region. Tony Gaston’s book, the first monographic treatment of any North Pacific alcid, is one encouraging sign that seabird research in the temperate North Pacific is coming of age.
Strontium and magnesium contents of some natural peralkaline silicic glasses and their petrogenetic significance
No abstract available.
2019 Forest Service–NASA Joint Applications Workshop: Satellite data to support natural resource management: A framework for aligning NASA products with land management agency needs
In 2019, about 103 participants from the U.S. Department of Agriculture’s Forest Service (Forest Service), the National Aeronautics and Space Administration (NASA) and other federal, private, and academic entities attended the Forest Service–NASA Joint Applications Workshop. The objective of this workshop was to increase awareness and understanding of the capabilities of NASA data products, and strengthen partnerships between NASA and the Forest Service. In this vein, the workshop sought to identify opportunities for collaboration between the Forest Service and NASA on the topics of (1) soil moisture and hydrology, (2) carbon emissions and flux, and (3) vegetation structure and function. Four key high-level opportunities for increased coordination and collaboration were identified including: (1) develop a strategic framework for collaboration and coordination; (2) establish working groups and engage in early adopter programs; (3) distill needs requirements and conduct feasibility studies; and (4) integrate tools and data. Although the workshop was conducted 4 years ago, the information is still highly relevant, since GTAC (Appendix B) and the SMAP, NISAR, ICESAT-2, CMS Programs are all still very active and numerous points of collaboration between the Forest Service and NASA have occurred.
Timing and nature of tertiary plutonism and extension in the Grouse Creek Mountains, Utah
The Grouse Creek -Albion-Raft River metamorphic core complex in northwestern Utah and southern Idaho is characterized by several Tertiary plutons with a range of ages and crosscutting relations that help constrain the timing of extensional deformation. In the Grouse Creek Mountains , at least three distinct, superimposed, extension -related Tertiary deformational events are bracketed by intrusive rocks, followed by a fourth event: motion on range-bounding faults. The Emigrant Pass plutonic complex was emplaced at depths of less than 10 km into Permianage rocks. SHRIMP U-Pb zircon analysis indicates a three-stage intrusion of the complex at 41.3 ± 0.3 Ma, 36.1 ± 0.2 Ma, and 34.3 ± 0.3 Ma. The two youngest phases represent distinctly younger intrusive event(s) than the oldest phase, separated by more than 5 m.y. The oldest phase cuts several metamorphosed and deformed younger-on-older faults, providing a pre-41 Ma age bracket for oldest extension -related deformation in the region. The youngest phase(s) are interpreted to have been intruded during development of a map-scale, N-S-trending recumbent fold, the Bovine Mountain fold, formed during vertical shortening of roof rocks during intrusion. This second event folded older normal faults that are likely pre-41 Ma. Zircons from the youngest part of the pluton show inheritance from Archean basement (~2.5 Ga) and from its Proterozoic sedimentary cover (~1.65 Ga). The Red Butte pluton, emplaced at 15-20 km depth, intruded highly metamorphosed Archean orthogneiss at 25.3 ± 0.5 Ma; cores of some zircons yield latest Archean ages of 2.55 Ga. The pluton is interpreted to have been intruded during a third deformational and metamorphic event that resulted in vertical flattening fabrics formed during NW to EW stretching, ultimately leading to thinning of cover and top-to-the west motion on the Ingham Pass fault. The Ingham Pass fault represents an important structure in the Grouse Creek Mountains , as it juxtaposes two parts of the crust that apparently resided as much as 10 km apart ( in depth) at times as young as the Miocene. The varied structural, metamorphic, and intrusive relations observed in the Grouse Creek Mountains reflect their formation at different levels within the crust. Data from these various levels argue that plutonism has been a key mechanism for transferring heat into the middle and upper crust, and localizing strain during regional extension . Interestingly, events documented here correlate in a broad way with cooling events documented in the Raft River Mountains , although plutons are not exposed there. Major and trace element geochemistry imply a crustal component in all of the studied plutons, indicating significant degrees of crustal melting at depth during extension , and point to mantle heat sources during the timespan of Basin and Range extension as the cause of melting. Basin and Range faulting and final uplift of the range is recorded by apatite fission track ages, averaging 13.4 Ma, and deposition of about 2 km of syn-faulting basin fill deposits along the Grouse Creek fault mapped along the western flank of the range. Similar apatite ages from the Albion Mountains to the north indicate that the western side of the Albion-Raft River- Grouse Creek core complex behaved as a single rigid crustal block at this time.
Scale growth rates and scale circulus deposition rates of marine-stage Atlantic salmon Salmo salar raised under semi-natural conditions
Scale circuli yield valuable information about the life history, age, and growth of a fish. However, because circuli formation is influenced by somatic growth, the rate at which circuli are formed and the factors influencing these rates must be taken into account for the given life stage of the study species. Scales were collected from Atlantic salmon raised in marine net pens off of the coast of Maine in order to characterize the formation of scale circuli and the growth of scales during the ocean phase, and to relate circulus deposition and scale growth rate to water temperature. Fish were sampled 13 times over a period of 25 months. Neither circulus deposition rate nor growth rate were constant through time and the same trend held when circulus deposition and growth were related to thermal experience. Both rates decreased over the course of the study, presumably related to the fish reaching sexual maturity. The results of this study indicate that the pattern of circulus deposition and scale growth of Atlantic salmon vary greatly during the early marine phase, and this dynamic should be taken into account when assessing growth, especially over short time periods.
Nomenclatural notes and identification of small-eared shrews (Mammalia: genus Cryptotis) from Cobán, Guatemala, in The Natural History Museum, London
A small series of shrews collected in Guatemala and registered in the British Museum between 1843 and 1907 includes parts of type series for three species: Corsira tropicalis Gray (1843), Sorex micrurus Tomes (1862), and Blarina tropicalis Merriam (1895). These three names are now considered equivalent, but my recent review of the specimens comprising the series indicates that they include three distinct species: Cryptotis merriami Choate (1970), Cryptotis oreoryctes Woodman (2011), and Cryptotis tropicalis (Merriam 1895). I review the taxonomic history of these specimens, provide current identifications tied directly to museum register numbers, describe how to distinguish the three species, and provide revised synonymies for these species.
Distinguishing natural sources from anthropogenic noise in seismic data
No abstract available.
Floristic surveys of Saguaro National Park Protected Natural Areas
No abstract available at this time