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Foster, Bryan - - 1999
We investigated temporal and spatial patterns of woody plant establishment in the first 7 y of succession in southwest Michigan old fields. From the 2nd to the 7th y following agricultural abandonment we conducted annual demographic surveys of woody plants and mapped all stems in six 10 x 20 m ...
Pinder, J. E. - - 1999
Rates of deforestation and reforestation were measured using Landsat Multispectral Scanner data for a 100-km by 100-km section of the Upper Coastal Plain of South Carolina and Georgia. Landsat data from 1974, 1979, 1984, 1988 and 1991 were (1) classified as pine forest, hardwood forest and nonforested areas and (2) ...
Wilder, Christine - - 1999
Canopy gaps in a second growth forest in East Tennessee were studied to document succession, sapling species partitioning in individual gaps and possible sapling adaptations for gap colonization. Ten gaps (64 to 309 [m.sup.2], mean = 186 [m.sup.2]) and four closed canopy plots (200 [m.sup.2] each) were surveyed. All trees ...
- - 1999
Loggerhead shrikes were observed using barbed wire to anchor and tear nest-lining materials in Indiana. This is a previously unreported function of impaling by shrikes and may explain the impaling of certain inedible objects.
- - 1999
The influence of predation risk on microhabitat selection in male adult deer mice (Peromyscus maniculatus) was examined using an enclosure experiment. The relative amount of time spent by the deer mice on coniferous leaf litter, hardwood leaf litter and logs was measured. Mice preferred dry coniferous litter over dry hardwood ...
- - 1999
Sternotherus odoratus (Latreille) is reported from a Holocene peat deposit in northern Indiana. In addition to turtle bones, sediment included subfossils of aquatic plants (Najas flexilis, Ceratophyllum demersum, Brasenia schreberi, Nymphaea odorata, Drepanocladus aduncus, Calliergon stramineum, Meesia triquetra), a gastropod (Gyraulus parvus) and fish (Centrarchidae). Vascular plant fragments from the ...
Stolley, Dorie - - 1999
Research on ducklings and goslings has demonstrated that young birds hatched in moderate to high saline environments without access to fresh drinking water grow and develop slower, and have increased mortality rates. Most direct saline-induced mortality happens before day 6 of life, after which time the nasal salt glands become ...
Schweitzer, Sara - - 1999
We measured habitat characteristics in colony sites and at nest sites of endangered least terns (Sterna antillarum athalassos) on an expansive alkaline flat at Salt Plains National Wildlife Refuge, Oklahoma, in 1992 and 1993. Least terns nested in 12 colony sites on the alkaline flat during 1992 and 1993. Number ...
Horner, John - - 1999
We examined the influence of plant genotype and early-season water deficits on oviposition preference and several measures of offspring performance in the goldenrod ball gallmaker (Eurosta solidaginis). Replicates of eight genotypes of goldenrod (Solidago altissima; Asteraceae), subjected to one of two watering regimes, were exposed to mass-released E. solidaginis. Oviposition ...
Spieler, M. - - 1999
Thirty-four anuran species in Comoe National Park, Ivory Coast (West Africa), were checked for infestation by larvae of the intradermal chigger mite, Endotrombicula pillersi (Acarina: Trombiculidae) for 5 y (1991-1995). Endotrombicula pillersi is a species-specific parasite of Phrynobatrachus francisci (Anura: Ranidae) at this site. Up to 84% of these frogs ...
Lindeman, Peter - - 1999
Von Bertalanffy growth-curve parameters were calculated from plastral annuli of specimens of Graptemys ouachitensis and G. pseudogeographica kohnii captured in western Kentucky, and museum specimens of G. ernsti from Alabama and G. caglei (males only) from Texas. Males had estimated values of k (intrinsic rate of growth toward asymptotic plastron ...
O'Brien, Christine - - 1999
The reproductive biology, glochidial morphology and recruitment of the federally endangered shinyraved pocketbook, Lampsilis subangulata, were studied from May 1995 to July 1996 in the Flint River system, Georgia. Gravid female L. subangulata were found nine months of the year. On 19 May 1995, a L. subangulata was discovered releasing ...
Ghent, Arthur - - 1999
In the mid 1930s, A.G. Huntsman hypothesized that in the Miramichi River. New Brunswick, predation by kingfishers and American mergansers upon Atlantic salmon (Salmo salar) parr became especially severe in years of low July-August rainfall, these years being reflected 3 y later by reduced commercial catches. Huntsman attempted to demonstrate ...
Shealer, D.A. - - 1999
We document the use of goldenrod (Solidago spp.) gall insects by eastern gray squirrels (Sciurus carolinensis) as a winter food resource. We also examined the foraging patterns of gray squirrels on these gall insects by presenting goldenrod gall feeders at ten sites around Hamilton. New York, during the winters of ...
Lariviere, Serge - - 1999
In the Canadian prairies maternal dens of striped skunks (Mephitis mephitis) are often located under a building in a farmstead. However, not all farmsteads or buildings are used by skunks, suggesting that striped skunks have specific preferences. To test this hypothesis, we measured a variety of parameters of farmsteads and ...
Bender, Louis - - 1999
We investigated the annual pattern of elk (Cervus elaphus) social group sizes and associations in Michigan's nonmigratory herd. Group observations were used to determine social group sizes and patterns throughout the year. Social group associations of individual elk were determined from 31 cow and 20 bull elk equipped with radio-collars. ...
Kotler, Burt - - 1999
Food storage in animals allows foragers to reap when food is plentiful and costs are low and eat when food is scarce and costs are high, thus shifting resources from periods of low value or high availability to periods of high value or low availability. To a caching animal, a ...
Cypher, Brian - - 1999
The effect of ingestion by coyotes (Canis latrans) and raccoons (Procyon lotor) on seed germination was investigated for four tree species in Illinois. The germination rate of persimmon (Diospyros virginiana) seeds ingested by raccoons was significantly higher than the rate for uningested seeds. Both were significantly higher than the rate ...
Eom, Ahn-Heum - - 1999
Tallgrass prairie sites subjected to 10 y of annual burning, mowing, nitrogen (N) fertilization or phosphorus (P) fertilization and untreated reference sites were studied to examine effects of these management practices on arbuscular mycorrhizal (AM) symbiosis. Spring burning of native prairie field plots significantly reduced AM fungal species diversity, while ...
Lentz, Kendra - - 1999
The effect of intraspecific competition and nutrient supply on the endangered northeastern bulrush, Scirpus ancistrochaetus, was examined in a full-factorial greenhouse experiment. Seedlings were exposed to 4 densities (1, 5, 10 or 25 plants/pot) and 3 nutrient concentrations (3, 25 or 50% of full strength) for 9 wk. Height, mass ...
Nagy, Eric - - 1999
The release of anthers held under tension which catapult pollen onto the stigma near the end of floral life has been proposed as a mechanism for autonomous self-fertilization in normally outcrossing Kalmia latifolia. We examined the importance of this delayed autonomous self-pollination to fruit production and the efficiency of the ...
Hyatt, Laura - - 1999
Although much is known about variation in both seed bank composition and disturbance effects in temperate deciduous forests, understanding of how these components interact to determine the importance of seed banks to regeneration is limited. To examine the interactive influences of seed bank composition and postdisturbance environment on seed bank ...
Wall, Dennis - - 1999
Twelve belt transects were used to sample woody vegetation in a 110-y-old regrowth forest on a natural levee ridge bordering Bayou Sauvage, Orleans Parish, Louisiana. Elevation was measured along each transect and species flood tolerances, based upon measured elevational ranges, were assessed. Codominant native hardwoods included Celtis laevigata, Quercus virginiana ...
Jenkins, Michael - - 1999
Between 1993 and 1995 we sampled ground-layer vegetation on 150 plots in Facus-Acer saccharum/ Arisaema Mesic Slope and Quercus alba-Acer saccharum/Parthenocissus Dry-Mesic Slope forests to determine how the understory of these forests responded to forest management. Four different stand types, clear-cuts (2-12 ha), group-selection openings (0.11.6 ha), single-tree selection openings ...
Sasso, Christopher - - 1999
The genus Cryptotis has never been reported from the Florida Keys although the mammal has been recorded in peninsular Florida. Two researchers captured one shrew which was later verified by the University of Kansas Natural History Museum (NHM) as a shrew belonging to the family Cryptotis parva floridana. The specimen, ...
Williams, Rod - - 1999
Genetic polymorphisms were investigated in fishers (Mattes pennanti) using horizontal starch gel electrophoresis of allozymes. During the 1996-1997 fisher trapping season muscle and liver samples were collected from animals in New Hampshire, New York, Wisconsin, and West Virginia, whereas blood samples were collected from New Hampshire and New York animals ...
Smith, Douglas - - 1999
The Great Lakes region has come to be occupied by at least two species of Dreissena, the zebra mussel, D. polymorpha and the quagga mussel, D. bugensis. The species are distinguished on the basis of shell morphology and electrophoretic patterns. Comparisons of the posterior mantle regions reveals differences between the ...
Shipman, Paul - - 1999
We studied the diet and prey selection of Desmognathus brimleyorum in southeastern Oklahoma relative to salamander size class and availability of prey. We found significant differences in prey consumed by large and small size classes. Also, by comparison with invertebrate samples taken in one salamander habitat, prey selected by D. ...
Borgmann, Kathi - - 1999
Eastern hemlock (Tsuga canadensis) was a major component of mesic forests in the Upper Great Lakes region, but presently persists in only a few locations. Many of these stands experience poor regeneration due to herbivory by white-tailed deer (Odocoileus virginianus), suggesting that hemlock will become progressively less common in these ...
Baskin, Jerry - - 1999
Various growth parameters and the requirements for flowering of Senna (= Cassia) marilandica, an herbaceous polycarpic perennial native to the eastern United States, and Senna (= Cassia) obtusifolia, a pantropical-warm temperate annual weed, were compared in greenhouse and growth chamber studies. Relative growth rate (RGR) of seedlings-juveniles of S. marilandica ...
Howe, Henry - - 1999
Zizia aurea (L.) Koch (Apiaceae) planted in a tallgrass restoration near Viola, Wisconsin, declined in numbers in randomly assigned plots left unburned or burned in May (41 to 9 and 63 to 30 individuals, respectively), but tripled in numbers in plots burned in August (72 to 209). Fire intensity varied ...
Mossman, Catherine - - 1999
Fragmentation of habitat has been found to create dispersal barriers for some species. Less well understood is the possibility, that physical barriers to dispersal between habitat patches might be reinforced or modified by behavioral barriers. We assessed whether there are differences in aggressive behavior between Peromyscus leucopus from large continuous ...
Lei, Simon - - 1999
The incidence of infection and reproductive success of Phoradendron californicum (desert mistletoe) on its host, Acacia gregii (catclaw), was quantitatively investigated in two localities of the Las Vegas Valley, Nevada, from March through November 1997. Similar patterns were detected between the two study sites. The abundance of Phoradendron was significantly ...
Snyder, Douglas - - 1999
Enneacanthus gloriosus occurs in coastal plain drainages from New York to Florida and W to Mississippi, but little is known about its life history. Enneacanthus gloriosus is smaller and shorter-lived in Mississippi than in eastern populations. The spawning season of E. gloriosus ranges from April to September and gonadosomatic index ...
Walk, Jeffery - - 1999
We documented the occurrence of 12 bird species within Prairie Ridge State Natural Area, Jasper County, Illinois, a matrix of nine grassland tracts (range 7-120 ha, totaling 489 ha), from 1994 to 1997 and analyzed the presence of these species relative to the area of the nine grassland tracts. Grassland ...
Williams, Charles - - 1999
In the nonglaciated Allegheny Plateau of northwestern Pennsylvania ground-layer plant communities of headwater riparian forests are among the most species-rich of the region. We examined the influence of inundation potential (geomorphic surfaces with high, moderate or low probability of seasonal inundation) and forest overstory (stems [greater than or equal to]2.5 ...
Kelly, Liesl - - 1999
Larval food-limitation may be an important factor influencing growth of lepidopteran populations. We tested effects of food-limitation on larval growth of Vanessa cardui Linnaeus (Lepidoptera: Nymphalidae), the painted lady butterfly. Vanessa cardui is a major pest of corn and soybeans in Iowa, making it a species of special interest. Larvae ...
Ducey, Peter - - 1999
Bipalium adventitium Hyman, an exotic terrestrial planarian invading North America, is an aggressive predator on earthworms. The spread and ecological impact of this flatworm will be determined in part by the its interactions with potential predators and prey. In laboratory trials, we tested the ability of B. adventitium to prey ...
Layne, Jack R., - - 1999
Caterpillars of the eastern North American moth Pyrrharctia isabella (Lepidoptera: Arctiidae) overwinter under plant debris where they are exposed to subfreezing temperatures. We measured supercooling points (SCPs), susceptibility to ice formation in body fluids at temperatures above the SCP following contact with external ice (inoculative freezing), freeze tolerance, cryoprotectant accumulation ...
Melampy, M.N. - - 1999
The intensity of nest predation in small woodlots was compared across three regions in Ohio: (1) suburban Cuyahoga County, (2) semirural Lorain County and (3) rural Huron County. Artificial nests, each holding three Japanese quail eggs, were placed in seven Cuyahoga Co. woodlots, four Lorain Co. woodlots and four Huron ...
Garner, J.T. - - 1999
Quadrula metanevra were collected monthly from Pickwick Dam tailwater (Tennessee River mile 201.3), Tennessee, between July 1988 and June 1990. A total of 227 specimens were examined. The population consisted primarily of dioecious individuals (98%) and had an unequal sex ratio (1.5 female: 1 male). Histological examinations showed that typical ...
Wilson, Albert G., - - 1999
We used discriminant analysis to examine morphological variation within the Plethodon vandykei species group. Significant differentiation was found among the nine samples used in the study. Canonical discriminant analysis and UPGMA clustering of Mahalanobis' distances among samples revealed morphological divergence of P. vandykei and P. idahoensis. The greatest intraspecific differentiation ...
Fritz, Ken - - 1999
The distribution and diversity of macroinvertebrates in relation to bison crossings was studied for four seasons in a headwater reach of a tallgrass prairie stream. Species richness was significantly higher above crossings only during the fall. Summer samples revealed significantly higher EPT (richness within only Ephemeroptera, Plecoptera and Trichoptera) index ...
Steven, Janet - - 1999
Horsenettle (Solanum carolinense. Solanaceae) plants possess the ability to bear both hermaphroditic and male flowers on the same plant, a breeding system referred to as andromonoecy. As part of an ongoing investigation into the evolution and maintenance of andromonoecy in horsenettle we conducted a field investigation that addressed the following ...
Tso, I-Min - - 1999
This study investigates how recent foraging gain affects the web-building behavior of the garden spider, Argiope trifasciata, especially stabilimentum-building. Adult female spiders in the field and in cages were randomly assigned to two groups, fed and unfed. Spiders in the fed group received three grasshoppers each day; spiders in the ...
Karl, Michael - - 1999
The sustainability of natural grasslands is in large part dependent upon the successful ingress and propagation of alien plant species. We attempted to characterize the propagation potential of the dominant plant species of a southeastern Montana mixed-grass prairie community including two introduced grasses, Bromus japonicus and B. tectorum. Aboveground standing ...
Beliveau, Bethany - - 1999
We performed hand-pollinations to assess the compatibility, of crosses within and between long-styled (pin) and short-styled (thrum) morphs of Houstonia serpyllifolia and H. longifolia. For both species, percentage fruit-set and seed-set per capsule were significantly higher following intermorph (legitimate) than intramorph (illegitimate) crosses, as expected for distylous species. Fruit-set was ...
Vickery, Peter - - 1999
Over 75% of the seedlings of the endemic sandplain grassland perennial, northern blazing star (Liatris scariosa var novae-angliae), die within their first growing season. During a study of the reproductive ecology of this rare plant, we found 17 seedlings whose leaves had become completely desiccated and brown and were classified ...
Sietman, Bernard - - 1999
We document the occurrence of freshwater mussels living on bedrock, a substrate generally considered to be unsuitable. We found 54 individuals of six species in this habitat. Our observations support the hypothesis that substrate stability is an important component of mussel habitat.
Goldberg, Stephen - - 1999
Six hundred sixty-three Uta stansburiana from the San Gabriel Mountains, Los Angeles County, California collected at monthly intervals from February 1974 to January 1975 were examined for helminths. One species of cestode, Oochoristica macallisteri, two species of nematodes, Physaloptera retusa (larvae) and Spauligodon giganticus and one species of an oligacanthorhynchid ...
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