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At least 1,711 records · Page 95Linked to original sources
USGS1980

Waterfowl production estimates on forested wetlands from pair and brood counts

Waterfowl pair and brood counts and estimates of total brood utilization were obtained from 10 beaver (Castor canadensis) flowages in north-central Minnesota and compared with rank correlation techniques. Summing the data for each species, correlation between pair and brood censuses was significant ( p = 0.8304, P < 0.025). Similarly, using the flowages as replicate samples of a habitat type, correlation between pair and brood censuses was again significant (p = 0.6076, P < 0.05). These data suggest that both pair and brood censuses are suitable for developing indices to waterfowl recruitment on small wetlands in forested areas. Neither method, however, correlates significantly with total brood use of the flowages, a phenomenon not related in a cause-and-effect way to indices of population recruitment. Evaluation of waterfowl populations on wooded impoundments and beaver flowages is difficult, but amenable to ground census techniques. The demands of resource management may soon justify application of such methods to areas that cannot be adequately assessed by aircraft.

Wildlife Society Bulletin↗
USGS1982

Organochlorine residues in bats after a forest spraying with DDT

Background levels of DDT and its metabolites (ZDDT) were extremely low or not detected in five species of forest-dwelling bats in northeastern Oregon, i.e., areas not sprayed with DDT in 1974. Other organochlorine pesticides were rarely found and no polychlotinated biphenyls (PCBs) were detected at any time during the study. Four of five species of bats showed significant changes in Z:DDT residues in, their carcasses following the single DDT spray application. Myotis californicus and M. volans showed the highest post-spray carcass residues, 6.90 and 6.21 ppm (wet weight). respectively. Lasionycteris noctivagans and Eptesicus fuscus also showed an increase; however, M. evotis exhibited no significant post-spray change. By 1977 (3 years post-spray), residues declined and only M. californicus and M. volans contained levels that were significantly above those in the nonspray (control) area. We are uncertain if the elevated residue levels resulting from the DDT-spray project adversely affected any of the bats. An attempt to relate bat carcass ZDDT residues to food habits, through analysis of stomach contents, yielded no clear relationships.

Northwest Science↗
USGS1997

Early vegetational changes on a forested wetland constructed for mitigation

Changes in vegetation were studied on 15 acres of a 35 acre forested wetland created as a mitigation site in Anne Arundel County, Maryland during 1994-96. Meter-square sampling on four different hydrologic elevations determined that grasses initially dominated the area, but decreased from 59 percent in 1994 to 51 percent in 1995 and 30 percent in 1996. Herbaceous non-grass plants (forbs) increased from 19 percent to 56 percent in the three-year period. Area with no plant cover decreased from 21 percent in 1994 to 11 percent in 1995, and 10 percent in 1996. Woody plants comprised 2 percent of the cover in 1994, increased to 4 percent in 1995, and remained at 4 percent in 1996. The increase of woody plants was mainly from natural regeneration (pioneer) plants. Monitoring of the transplanted trees and shrubs indicated 35 percent mortality and little growth of surviving plants. The pioneer woody plant forming most of the cover was black willow (Salix nigra). Differences in the vegetation were observed among the four elevations, although no differences were observed for the major vegetation classes between plots that were planted and those that were not planted with woody plants. Dominant grass species was redtop (Agrostis stolonifera), which comprised 51 percent of the cover in 1994 and 42 percent cover in 1995 and 23 percent in 1996. Other species that were common were bush clover (Lespedeza cuneata), Japanese clover (Lespedeza striata) and flat pea (Lathyrus sylvestris). All four of these dominant species were part of the original seed mixtures that were seeded on the site. A total of 134 species of plants was recorded on the site indicating a fairly diverse community for a newly established habitat.

Wetland Journal↗
USGS1999

Abundance and reproduction of songbirds in burned and unburned pine forests of the Georgia Piedmont

We studied the abundance and productivity of songbirds in prescribed burned and unburned mature (>60 yr) pine forests at Piedmont National Wildlife Refuge, Georgia, during 1993-1995. We estimated species abundance, richness, and evenness using data from 312 point counts in 18 burned sites and six unburned sites. We measured gross habitat features in 0.04-ha circles centered on each point count station. We calculated productivity estimates at nests of seven of the most common nesting species. Habitat components we measured in 1-, 2-, and 3-yr post-burn sites were similar, but most components differed between burned and unburned sites. Although 98 species were detected during point counts, we report only on the 46 species that nested in the area and were detected >10% of the counts in either habitat class. Twenty-one species preferred burned sites and six preferred unburned sites. Avian species richness and evenness were similar for burned and unburned sites. Burned sites were preferred for nesting over unburned sites. Only nine nests of six species were found in unburned sites. Productivity estimates were low in burned sites. One or more eggs hatched in only 59 of 187 nests monitored, and an average of only 0.82 chicks per nest were estimated to have fledged. Predation was the most common probable cause for nest failure, ranging from 45% in the Northern Cardinal (Cardinalis cardinalis) to 64% in the Summer Tanager (Piranga rubra). Because the sources of predation at the refuge are unknown, future research should address this issue.

Journal of Field Ornithology↗
USGS2007

Design and implementation of estimation-based monitoring programs for flora and fauna: A case study on the Cherokee National Forest

Science-based monitoring of biological resources is important for a greater understanding of ecological systems and for assessment of the target population using theoretic-based management approaches. When selecting variables to monitor, managers first need to carefully consider their objectives, the geographic and temporal scale at which they will operate, and the effort needed to implement the program. Generally, monitoring can be divided into two categories: index and inferential. Although index monitoring is usually easier to implement, analysis of index data requires strong assumptions about consistency in detection rates over time and space, and parameters are often biasednot accounting for detectability and spatial variation. In most cases, individuals are not always available for detection during sampling periods, and the entire area of interest cannot be sampled. Conversely, inferential monitoring is more rigorous because it is based on nearly unbiased estimators of spatial distribution. Thus, we recommend that detectability and spatial variation be considered for all monitoring programs that intend to make inferences about the target population or the area of interest. Application of these techniques is especially important for the monitoring of Threatened and Endangered (T&E) species because it is critical to determine if population size is increasing or decreasing with some level of certainty. Use of estimation-based methods and probability sampling will reduce many of the biases inherently associated with index data and provide meaningful information with respect to changes that occur in target populations. We incorporated inferential monitoring into protocols for T&E species spanning a wide range of taxa on the Cherokee National Forest in the Southern Appalachian Mountains. We review the various approaches employed for different taxa and discuss design issues, sampling strategies, data analysis, and the details of estimating detectability using site occupancy. These techniques provide a science-based approach for monitoring and can be of value to all resource managers responsible for management of T&E species.

Proceedings of the Annual Conference of the Southe↗
USGS1977

Role of the wolf in a deer decline in the Superior National Forest

White-tailed deer (Odocoileus virginianus) declined in the Superior National Forest of Minnesota between 1968 and 1974. In a 3,000 sq km area of the poorest habitat, deer were decimated. Contributing factors were severe winters, deteriorating habitat, and wolves. Wolves killed older deer, but insufficient fawns were available to replace them.

Research Paper↗
USGS1973

Wolf numbers in the Superior National Forest of Minnesota

Seventy-seven radio-tagged wolves (Canis lupus), including members of 12 adjacent packs, were located more than 3000 times, and observed on 1337 occasions, from 1968 through mid-1973. Projected population estimates for the 4203 square-mile Forest were 405 plus or minus 20 for winter 1971-72, and 388 plus or minus 14 for winter 1972-73.

Research Paper↗
USGS1986

Deer population in the Central Superior National Forest, 1967-1985

Deer were aerially censused each winter from 1976 through 1985 in a 400-sq km2 area near Isabella, Minnesota, in the Central Superior National Forest; a correction factor based on aerial observability of radio-tagged deer in the same region was then applied to the census figures. Deer numbers, which had reached an estimated 3.5/sq km, declined drastically in the early 1970's, fluctuated between about 0.43 and 0.97/sq km from 1976 through 1985, and began increasing in 1983.

Research Paper↗
USGS2009

Mangrove forest recovery in the Everglades following Hurricane Wilma

On October 24th, 2005, Hurricane Wilma made landfall on the south western shore of the Florida peninsula. This major disturbance destroyed approximately 30 percent of the mangrove forests in the area. However, the damage to the ecosystem following the hurricane provided researchers at the Florida Coastal Everglades (FCE) LTER site with the rare opportunity to track the recovery process of the mangroves as determined by carbon dioxide (CO 2 ) and energy exchanges, measured along daily and seasonal time scales.

Florida↗
USGS1984

Courtright intrusive zone: Sierra National Forest, Fresno County, California.

This is a field guide to a well-exposed area of plutonic and metamorphic rocks in the Sierra National Forest, Fresno County, California. The plutonic rocks, of which three major bodies are recognized, besides aplite and pegmatite dykes, range 103 to approx 90 m.y. in age. Points emphasized include cataclastic features within the plutonic rocks, schlieren and mafic inclusions. (M.A. 83M/0035).-A.P.

California Geology↗
USGS1998

Effects of wet- and dry-season fires on Jacquemontia curtisii, a south Florida pine forest endemic

South Florida pine forests have a diverse endemic flora that has evolved under the influence of recurrent fire. We studied the response of Jacquemontia curtisii Peter ex Hallier f. (pineland clustervine), a perennial herbaceous member of that flora, to experimental fires during wet and dry seasons. In each of three populations, three treatments were applied: wet-season (June) prescribed fire, dry-season (January) prescribed fire, and an unburned control. Flowering, fruiting, and seedling establishment were followed for up to one year. Mortality of adult plants was twice as great after wet-season burns than after dry-season burns even though fire temperatures were higher in the dry-season burns. Within a season of burning, mortality was greater for the more severely burned plants or the smaller plants. Wet-season burns produced over three times more flowers than not burning, in spite of mortality of more than half the plants. Burning stimulated germination from the soil seed bank. Dry-season burns resulted in five times more seedlings than wet-season burns and more of these seedlings were alive one year after the burn. It is likely that the long-term viability of Jacquemontia curtisii populations is favored by diversity in fire season and severity.

Florida↗
USGS2003

Temporal and spatial stability of red-tailed hawk territories in the Luquillo Experimental Forest, Puerto Rico

We mapped Red-tailed Hawk (Buteo jamaicensis) territories in the Luquillo Experimental Forest (LEF) of Puerto Rico in 1998. We combined our 1998 data with that collected during previous studies of Red-tailed Hawks in the LEF to examine population numbers and spatial stability of territorial boundaries over a 26-yr period. We also investigated potential relationships between Red-tailed Hawk territory sizes and topographic and climatic factors. Mean size of 16 defended territories during 1998 was 124.3 ?? 12.0 ha, which was not significantly different from our calculations of mean territory sizes derived from data collected in 1974 and 1984. Aspect and slope influenced territory size with the smallest territories having high slope and easterly aspects. Territory size was small compared to that reported for other parts of the species' range. In addition, there was remarkably little temporal change in the spatial distribution, area, and boundaries of Red-tailed Hawk territories among the study periods. Further, there was substantial boundary overlap (21-27%) between defended territories among the different study periods. The temporal stability of the spatial distribution of Red-tailed Hawk territories in the study area leads us to believe the area might be at or near saturation.

Journal of Raptor Research↗
USGS2005

The role of organic matter in sediment budgets in forested terrain

The production and transport of suspended particulate matter usually are major components of a sediment budget, but the organic and inorganic fractions of this material are not commonly differentiated. In four forested streams in the northwestern United States, the organic content of suspended sediment samples ranged from 10 to 80 weight percent for individual flood events. For a given stream, as a percentage of suspended sediment, organic content was highest during base flows and the early rising and late falling limbs of hydrographs, but on an annual cumulative basis, most organic flux occurred during a few days of high flow. By weight, the inorganic component of suspended sediment dominated the annual sediment flux in three of the catchments, but organics represented more than half the suspended sediment load in an old growth redwood stream. Although commonly minor by weight, organic suspended sediment can have important effects on aquatic biological communities, turbidity measurements, and eutrophication in estuaries.

Conference Paper↗
USGS2007

Palynological correlation of Atokan and lower desmoinesian (Pennsylvanian) strata between the Illinois basin and the Forest City basin in Eastern Kansas

Palynological correlation is made between Atokan and lower Desmoinesian strata in the Illinois basin an the Forest City basin in eastern Kansas. Spore data from previous studies of coals in the Illinois basin and other coal basins are compared with data from spore assemblages in coal and carbonaceous shale bands in a core drilled in Leavenworth County, Kansas. Correlations are based on first and/or last occurrences of 31 species common to the Illinois basin and eastern Kansas and on significant increases or decreases in abundance of several of those taxa. The oldest coal, which is 26 ft (8 m) above the top of the Mississippian, is early Atokan (early Westphalian B) in age and is approximately equivalent to the Bell coal bed in the Illinois basin. The Riverton coal bed at the top of the studied interval in Kansas is early Desmoinesian (early Westphalian D) and correlates with about the Lewisport coal bed in the Illinois basin. Three coal beds near the base of the Pennsylvanian in three cores drilled in Cherokee County, Kansas, which were also studied, range in age from late Atokan to early Desmoinesian. As in other coal basins, Lycospora, borne by lycopod trees, greatly dominates the lower and middle Atokan spore assemblages in coals and shale, but spores from ferns, especially tree ferns, significantly increase in abundance in the upper Atokan and lower Desmoinesian. The pattern of change of dominance among Lycosporapellucida, L. granulata, and L, micropapillata in middle Atokan (Westphalian B-C transition) that has been demonstrated earlier in the Illinois basin and eastern Kentucky and Tennessee, also occurs in eastern Kansas. At least 10 species of spores, which appeared in the middle Atokan in other parts of the equatorial coal belt, also appeared at this time in eastern Kansas. Most of these species have their affinities with the ferns, which were adapted to drier habitats than lycopods. Thus, the climate may have become a little drier in the equatorial coal belt during middle Atokan.

Current Research in Earth Sciences↗
USGS2000

Macromoths of northwest forests and woodlands

The macromoths are a group of families within the order Lepidoptera. The macromoths in the woodlands and forests of the Pacific Northwest are represented by 1,200 species in 12 families: Arctiidae, Dioptidae, Drepanidae, Epiplemidae, Geometridae, Lasiocampidae, Lymantriidae, Noctuidae, Notodontidae, Saturniidae, Sphingidae, and Thyatiridae. In addition to the macromoths, the Lepidoptera are represented by the butterflies and skippers, and the micromoths. Butterflies possess a knob at the tip of the antennae while the tip of the antennae in skippers is typically hooked. The tip of the antennae in macromoths and micromoths is tapered. The differences between macromoths and micromoths is not literally based on size as the names suggest but rather in details of the female reproductive tract and wing venation. These details are discussed and illustrated in most texts on general entomology (Borror et al. 1989) and in books about Lepidoptera (Covell 1984).

California;Oregon;Washington;Idaho;Montana;British↗
USGS2013

Oak woodlands and forests fire consortium: A regional view of fire science sharing

The Joint Fire Science Program established 14 regional fire science knowledge exchange consortia to improve the delivery of fire science information and communication among fire managers and researchers. Consortia were developed regionally to ensure that fire science information is tailored to meet regional needs. In this paper, emphasis was placed on the Oak Woodlands and Forests Fire Consortium to provide an inside view of how one regional consortium is organized and its experiences in sharing fire science through various social media, conference, and workshop-based fire science events.

Conference Paper↗
USGS2014

Status of forest birds on Rota, Mariana Islands

The western Pacific island of Rota is the third largest human inhabited island in the Mariana archipelago, and is designated an Endemic Bird Area. Between 1982 and 2012, 12 point-transect distance sampling surveys were conducted to assess population status. Surveys did not consistently sample the entire island; thus, we used a ratio estimator to estimate bird abundances in strata not sampled during every survey. Occupancy models of the 2012 survey revealed general patterns of habitat use and detectability among 11 species that could be reliably modeled. The endangered Mariana crow ( Corvus kubaryi ) was dispersed around the periphery of the island in steep forested habitats. In contrast, the endangered Rota white-eye ( Zosterops rotensis ) was restricted to the high-elevation mesa. Precision of detection probabilities and occupancy estimates and effects of habitat types, sampling conditions, and specific observers varied considerably among species, indicating that more narrowly defined classifications and additional observer training may improve the accuracy of predictive modeling. Population estimates of five out of ten native bird species, including collared kingfisher ( Todiramphus chloris orii ), Mariana crow, Mariana fruit-dove ( Ptilinopus roseicapilla ), Micronesian myzomela ( Myzomela rubrata ), and white-throated ground-dove ( Gallicolumba xanthonura ) declined over the 30-year time series. The crow declined sharply to fewer than 200 individuals (upper 95% confidence interval). Trends increased for Micronesian starling ( Aplonis opaca ), rufous fantail ( Rhipidura rufifrons mariae ), and white tern ( Gygis alba ). Rota white-eye numbers declined from 1982 to the late 1990s, but returned to 1980s levels by 2012. The trend for the yellow bittern ( Ixobrychus sinensis ) was inconclusive. The alien Eurasian tree sparrow ( Passer montanus ) apparently increased in number despite an unreliable trend assessment. Declines were noted in the other two alien birds, black drongo ( Dicrurus macrocercus ) and island collared-dove ( Streptopelia bitorquata ). Total bird densities on Rota were similar to those on Saipan and Tinian, which were lower than densities on Aguiguan. Overall, bird trends on Rota declined, whereas trends observed for the same period on Saipan and Tinian were mixed, and trends on Aguiguan were stable to increasing. We identified several sampling design and protocol procedures that may improve the precision of occupancy, status, and trend assessments. Continued monitoring and demographic sampling are needed to understand why most bird species on Rota are declining, to identify the causative agents, and to assess effectiveness of conservation actions for rare species, especially the Mariana crow.

Marianas Islands↗