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Density estimation and survey validation for swift fox Vulpes velox in Oklahoma

100%

Criffield M. A., Hellgren E. C., Leslie,Jr D. M.

Acta Theriologica

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2010

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tom 55

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nr 1

53-60

The swift fox Vulpes velox Say, 1823, a small canid native to shortgrass prairie ecosystems of North America, has been the subject of enhanced conservation and research interest because of restricted distribution and low densities. Previous studies have described distributions of the species in the southern Great Plains, but data on density are required to evaluate indices of relative abundance and monitor population trends. We examined regressions of swift fox density (estimated by mark-recapture) on timed-track surveys, scat surveys, and catch-per-unit effort indices. Seventy-nine swift foxes (42 male, 37 female) were captured 151 times during 10 240 trapnights between May 2003 and December 2004 in the Panhandle of Oklahoma, USA. Density estimates, based on mark-recapture data from autumn 2004, were 0.08–0.44 foxes/km2. Survey indices explained 51 to 76% of the variation in estimates of fox density. Our study indicates that surveys of time-to-track encounters and scat deposition rates show promise in monitoring trends in population abundance over large areas.

2

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Exceptional cameral deposits in a sublethally injured Carboniferous orthoconic nautiloid from the Buckhorn Asphalt Lagerstatte in Oklahoma, USA

84%

Seuss B., Mapes R. H., Klug C., Nutzel A.

Acta Palaeontologica Polonica

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2012

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tom 57

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nr 2

The cameral and intrasiphonal deposits of a Pennsylvanian straight nautiloid (Pseudorthoceratidae) are studied in order to understand the formation of these deposits. The specimens from the Buckhorn Asphalt deposit (Oklahoma) are exceptionally preserved including original aragonite and microstructures. The specimen investigated survived a predation attempt and shows bite marks on the phragmocone. This is the second report of an ectocochleate cephalopod and first report of an orthoconic nautiloid which survived massive damage of conch and siphuncle. For the first time, a high−magnesium calcitic mineralogy of cameral deposits is documented. These deposits were formed in alternation with aragonite in a chamber which was perforated during the unsuccessful predation attempt. The animal formed the chamber deposits throughout its entire lifetime and the siphuncle played a major role in formation of the cameral deposits.

3

Primitive boreosphenidan mammal [?Deltatheroida] from the Early Cretaceous of Oklahoma

84%

Kielan-Jaworowska Z., Cifelli R. L.

Acta Palaeontologica Polonica

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2001

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tom 46

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nr 3

We describe a new boreosphenidan mammal, Atokatheridium boreni gen. et sp. n., from the Early Cretaceous of Oklahoma, based on an upper molar and a tentatively referred lower molar. The upper molar is characterized by a small protocone and unwinged conules, broad stylar shelf, paracone taller than metacone, and lack of pre- and postcingula. Comparisons with relevant Early and Late Cretaceous boreosphenidans suggest closest similarity to Deltatheroida, including one character (extreme development of the distal stylar shelf, which projects labially and lacks cusps) interpreted as derived. The tentatively attributed lower molar shows similarity to Deltatheridium and the ?aegialodontid genus Kielantherium in having the paraconid higher than the metaconid, but differs from Kielantherium in having a differently shaped talonid. From Aegialodon it differs in having a vertically oriented (rather than semi-procumbent) paraconid and a larger talonid. We figure also two isolated trigonids, differing in size, which show some resemblance to that of ?Atokatheridium. Deltatheroidans, despite their generally primitive dental morphology, are otherwise surely known only from the Late Cretaceous, and are largely restricted to the Old World. If a deltatheroidan, the new taxon implies a significant temporal range extension for the group, and provides another biogeographic link between Cretaceous mammals of Asia and North America.

4

Nest sites and conservation of endangered Interior Least Terns Sterna antillarum athalassos on an alkaline flat in the South-Central Great Plains [USA]

84%

Winton B. R., Leslie D.M.,Jr.

Acta Ornithologica

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2003

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tom 38

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nr 2

We monitored nest sites of endangered Interior Least Terns on a 5 095 ha alkaline flat in north-central Oklahoma, USA. After nest loss, Least Terns commonly renested and experienced 30% apparent nest success in 1995-1996 (n = 233 nests). Nest success and predation differed by location on the alkaline flat in 1995 and overall, but nest success and flooding did not differ by microhabitat type. Predation was highest at nests ≤ 5 cm from debris (driftwood/hay) in 1995. No differences in nesting success, flooding, or predation were observed on comparing nests inside and outside electrified enclosures. Coyotes and Striped Skunks were confirmed nest predators, and Ring-billed Gulls were suspected nest predators. We identified one location on the alkaline flat of about 1 000 ha with consistently lower nest losses attributable to flooding and predation and the highest hatching success compared with other parts of the alkaline flat; it was typified by open ground and bisected by several creeks. Management activities that minimize flooding and predation in this area could further enhance nest success and theoretically increase overall productivity of this population of Least Terns. However, the efficacy of electrified enclosures and nest-site enhancements, as currently undertaken, is questionable because of considerable annual variation in use by and protection of Least Terns.

5

Nowy stary czempionat

71%

Zbyszewski J.

Araby

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2008

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nr 4(12)

6

The paleoecology of the Late Miocene mammals from the Optima Local Fauna of Oklahoma, USA

67%

Frederickson J. A., Cohen J. E., Engel M. H., Hunt T. C., Wilbert G. A., Castaneda O. S., Czaplewski N. J.

Acta Palaeontologica Polonica

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2022

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tom 67

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nr 1

7

Competition in sympatric white-tailed deer and cattle populations in southern pine forests of Oklahoma and Arkansas, USA

67%

Jenks J. A., Leslie D. M., Lochmiller R. L., Melchiors M. A., McCollum III F. T.

Acta Theriologica

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1996

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tom 41

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nr 3

Inferences on competitive interactions between white-tailed deer Odocoileus uirgi- nianus (Zimmermann, 1780) and cattle were made using information on diet composition and quality. We hypothesized that dietary overlap between deer and cattle would increase with cattle density and that quality of deer diets would be higher in areas not exposed to cattle than in areas that were stocked with moderate to high cattle densities. Three treatments were delineated in McCurtain County, Oklahoma (heavy cattle stocking), and Howard (moderate to light cattle stocking) and Pike (no cattle stocking) counties, Arkansas. Treatments were similar with respect to soils and vegetation but differed with respect to cattle stocking rate (ie number of cattle/ha). Deer and cattle diets and concentrations of fecal nitrogen (FN) {an index to dietary quality) were determined from feces that were obtained from .12 randomly selected collection areas (4/treatment) from October 1986 to October 1988. Dietary overlap of deer and cattle was highest in winter and lowest in summer. Dietary overlap of deer populations was lowest for populations exposed to heavy cattle stocking and no cattle stocking, which suggested that competition between the deer and cattle occurred in winter. Fecal nitrogen was iowest in deer feces collected from treatments with cattle stocking in February but higher in August and October. Both dietary quality and dietary overlap suggested possible competitive interactions between deer and cattle in winter. However, higher dietary forb and dietary quality for deer in summer exposed to cattle suggested that cattle can facilitate growth of early successional plant species in pine habitats.

8

Osteology, paleobiology, and relationships of the sauropod dinosaur Sauroposeidon

67%

Wedel M. J., Cifelli R. L., Sanders R. K.

Acta Palaeontologica Polonica

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2000

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tom 45

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nr 4

Sauroposeidon proteles is a large brachiosaurid sauropod recently described from the Antlers Formation (Aptian-Albian) of southeastern Oklahoma. Sauroposeidon represents the culmination of brachiosaurid trends toward lengthening and lightening the neck, and its cervical vertebrae are characterized by extensive pneumatic structures. The elaboration of vertebral air sacs during sauropod evolution produced a variety of internal structure types. We propose a new classification system for this array of vertebral characters, using computed tomography (CT) of pneumatic internal structures. Comparisons with birds suggest that the vertebrae of sauropods were pneumatized by a complex system of air sacs in the thorax and abdomen. The presence of a thoraco-abdominal air sac system in sauropods would dramatically affect current estimates of mass, food intake, and respiratory requirements. Sauroposeidon was one of the last sauropods in the Early Cretaceous of North America; sauropods disappeared from the continent by the early Cenomanian. The demise of sauropods in the Early Cretaceous of North America predates significant radiations of angiosperms, so the decline and extinction of this dinosaur group cannot be linked to changes in flora.

9

Wiercenia i drżenia

67%

Kuchment A.

Świat Nauki

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2016

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nr 08

10

Reappraisal of the tribosphenidan mammals from the Trinity Group (Aptian-Albian) of Texas and Oklahoma

59%

Davis B. M., Cifelli R. L.

Acta Palaeontologica Polonica

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2011

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tom 56

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nr 3

The Trinity therians have long been the focus of attempts to reconstruct the evolutionary history of higher mammals, especially in the context of the development of tribospheny. In this paper, we update the taxonomy of the tribosphenidan taxa known from the Trinity Group and establish with more confidence the premolar/molar count in each. Many isolated specimens can be referred to a specific tooth locus. Additional diversity is revealed within the Deltatheroida, with the description of an additional species of Oklatheridium; Pappotherium is here considered a likely metatherian based on the inferred presence of four molars, while Holoclemensia is a basal eutherian (the opposite of some traditional interpretations). The remainder of the genera, Kermackia and Slaughteria, cannot be allied with either of the living groups of tribosphenidan mammals using the available data. We identify strong morphological diversity within this assemblage of stem taxa, including modifications to the traditional tribosphenic occlusal pattern in Kermackia. Mammalian evolution at the base of the tribosphenidan radiation was complex, and this underscores the need for caution when interpreting the morphology and relationships of taxa known by incomplete material.

Ograniczanie wyników

Density estimation and survey validation for swift fox Vulpes velox in Oklahoma

Exceptional cameral deposits in a sublethally injured Carboniferous orthoconic nautiloid from the Buckhorn Asphalt Lagerstatte in Oklahoma, USA

Primitive boreosphenidan mammal [?Deltatheroida] from the Early Cretaceous of Oklahoma

Nest sites and conservation of endangered Interior Least Terns Sterna antillarum athalassos on an alkaline flat in the South-Central Great Plains [USA]

Nowy stary czempionat

The paleoecology of the Late Miocene mammals from the Optima Local Fauna of Oklahoma, USA

Competition in sympatric white-tailed deer and cattle populations in southern pine forests of Oklahoma and Arkansas, USA

Osteology, paleobiology, and relationships of the sauropod dinosaur Sauroposeidon

Wiercenia i drżenia

Reappraisal of the tribosphenidan mammals from the Trinity Group (Aptian-Albian) of Texas and Oklahoma