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At least 1,063 records · Page 59Linked to original sources
USGS2006

Should heterogeneity be the basis for conservation? Grassland bird response to fire and grazing

In tallgrass prairie, disturbances such as grazing and fire can generate patchiness across the landscape, contributing to a shifting mosaic that presumably enhances biodiversity. Grassland birds evolved within the context of this shifting mosaic, with some species restricted to one or two patch types created under spatially and temporally distinct disturbance regimes. Thus, management-driven reductions in heterogeneity may be partly responsible for declines in numbers of grassland birds. We experimentally altered spatial heterogeneity of vegetation structure within a tallgrass prairie by varying the spatial and temporal extent of fire and by allowing grazing animals to move freely among burned and unburned patches (patch treatment). We contrasted this disturbance regime with traditional agricultural management of the region that promotes homogeneity (traditional treatment). We monitored grassland bird abundance during the breeding seasons of 2001-2003 to determine the influence of altered spatial heterogeneity on the grassland bird community. Focal disturbances of patch burning and grazing that shifted through the landscape over several years resulted in a more heterogeneous pattern of vegetation than uniform application of fire and grazing. Greater spatial heterogeneity in vegetation provided greater variability in the grassland bird community. Some bird species occurred in greatest abundance within focally disturbed patches, while others occurred in relatively undisturbed patches in our patch treatment. Henslow's Sparrow, a declining species, occurred only within the patch treatment. Upland Sandpiper and some other species were more abundant on recently disturbed patches within the same treatment. The patch burn treatment created the entire gradient of vegetation structure required to maintain a suite of grassland bird species that differ in habitat preferences. Our study demonstrated that increasing spatial and temporal heterogeneity of disturbance in grasslands increases variability in vegetation structure that results in greater variability at higher trophic levels. Thus, management that creates a shifting mosaic using spatially and temporally discrete disturbances in grasslands can be a useful tool in conservation. In the case of North American tallgrass prairie, discrete fires that capitalize on preferential grazing behavior of large ungulates promote a shifting mosaic of habitat types that maintain biodiversity and agricultural productivity. ?? 2006 by the Ecological Society of America.

Ecological Applications↗
USGS1994

Emperor goose (Chen canagica)

Early naturalists exploring western Alaska were intrigued to find a stocky, blue-gray species of coastal goose unique to that area and nearby Russia. As E. W. Nelson (1887) wrote, "Among the various species of birds more or less peculiar to Alaska this goose is perhaps the most noteworthy." The Emperor Goose nests in the extensive coastal salt marsh habitats of arctic and sub-arctic Alaska and Russia and winters primarily on coastal beaches along ice-free areas of the Aleutian Islands and the Alaska Peninsula. Locally known as the "Beach Goose" from its habit of roosting and feeding near the waters' edge, the diet of this species consists largely of clams, mussels, and algae when wintering and staging in marine and estuarine habitats. When nesting in terrestrial habitats, it eats mostly roots, bulbs, and shoots of vegetation. Although the breeding biology and habitat requirements of this goose have been examined in detail, mostly on the Yukon-Kuskokwim Delta (Y-K Delta) of Alaska, there have been no intensive studies of its wintering or staging biology. Recent studies of migration have confirmed pathways and timing between the Y-K Delta and staging areas on the Alaska Peninsula and wintering areas largely on the Aleutian Islands (Hupp et al. 2007). Observations of substantial molt migrations to the Chukotka Peninsula in eastern Russia (Hupp et al. 2007) suggest a possible change in distribution, or at least a clarification, and raise the possibility of harvest mortality on both continents. Alaska's Emperor Goose population declined precipitously from 139,000 in 1964 to 42,000 in 1986, although its numbers have recovered slightly since then (Fischer et al. 2008). The factors responsible for this quick decline and slow recovery remain poorly known. Hunting, especially subsistence hunting by Native Americans, is probably a factor (Hupp et al. 2008b); coastal oil pollution could also be reducing the survival of overwintering individuals (Byrd et al. 1995); and interspecific competition among brood rearing geese may limit recovery through recruitment (Schmutz and Laing 2002, Lake et al. 2008).

Birds of North America↗
USGS2001

Conodont and fusulinid biostratigraphy and history of the Pennsylvanian to Lower Permian Keeler Basin, east-central California

The Pennsylvanian-Lower Permian Keeler Canyon Formation and lower part of the Lower Permian Lone Pine Formation in east-central California were deposited in a deep-water basin that originated in the Morrowan (Early Pennsylvanian), was fully established by the Desmoinesian (Middle Pennsylvanian), and lasted into the Sakmarian (Early Permian). Stratigraphic studies indicate that the Keeler Canyon Formation can be divided into members recognizable throughout the area of our detailed mapping. From older to younger they are the Tinemaha Reservoir, Tihvipah Limestone, Cerro Gordo Spring, and Salt Tram Members. Rocks in this basin, here referred to as the Keeler basin, contain numerous fusulinid and conodont faunas most of which were deposited by sediment-gravity flows probably originating at the margin of the Bird Spring carbonate platform to the northeast. Sixty-one species of Atokan to Sakmarian fusulinids and 38 species of Desmoinesian to Sakmarian conodonts are recognized. These, in addition to four species of Morrowan conodonts previously reported, show that every stage from the Morrowan to Sakmarian is represented in the basin. The fusulinid faunas are composed largely of taxa of the North American craton, especially the south-central USA, with important endemic constituents and some McCloud Limestone forms, representing the Eastern Klamath terrane. Conodonts are closely similar to species in the Ural Mountains region of Russia and Kazakhstan, as well as the American midcontinent. The co-occurrence of fusulinids and conodonts in the Keeler basin results in a better correlation of zones based on these two groups of fossils than generally is possible.

Brigham Young University Geology Studies↗
USGS1989

Population trends of North American shorebirds based on the International Shorebird Survey

Shorebirds Charadrii are prime candidates for population decline because of their dependence on wetlands that are being lost at a rapid pace. Thirty-six of the 49 species of shorebirds that breed in North America spend most of the year in Latin America. Because populations of most species breed and winter at remote sites, it may be most feasible to monitor their numbers at migration stopovers. In this study, we used statistical trend analysis methods, developed for the North America Breeding Bird Survey, to analyze data on shorebird populations during southbound migration in the United States. Survey data were collected by volunteers in the International Shorebird Survey (ISS). The analyses indicate that whimbrels Numenius phaeopus , short-billed dowitchers Limnodromus griseus , and sanderlings Calidris alba have undergone statistically significant declines. Methodological concerns over both the ISS and the trend analysis procedures are discussed in detail and biological interpretations of the results are suggested.

Biological Conservation↗
USGS1943

Age determination in juvenal bobwhite quail

Following methods described by Louis Bureau (1911, 1913) in France, tabulations were made (1) of the ages at which captivity-reared bob-white quail ( Colinus virginianus ) dropped their juvenal remiges, and (2) the rates at which post-juvenal replacement primaries grew. These were arranged so as to permit the determination of age in healthy birds from one to five months of age. The degree of individual variation was much greater than that found by Bureau, however, and limits accuracy in age determination after the 10th week. The post-juvenal wing molt began on the birds' 28th day and ended when the quail were 146 to 154 days old. The post-juvenal body molt was found to take place largely between the 70th and 100th days. The juvenal rectrices were renewed from the 62nd to the 122nd days, the new feathers being as long as their longest coverts when the birds were 116 days old. The color of the tarsi varied from pink, at 32 days of age, to straw color at 60 days, and yellow-gray from 83 to 180 days. At six months, the color of the beak was identical with that of adults. Unlike several other game bird species, the flexibility of the lower jaw was not an accurate index to age in bob-whites older than 11 weeks. Rigor mortis and freezing were found to hinder the testing of this criterion.

American Midland Naturalist↗
USGS2003

Science support for managing migratory waterfowl.

Migratory birds in North America are an international resource shared by Canada, the United States, and Mexico. Ultimate population management authority in the U.S. lies with the U.S. Fish and Wildlife Service (FWS), but states participate in development of management decisions through the Flyway system. The FWS, state wildlife agencies, and nongovernmental organizations participate through independent actions and cooperative Joint Ventures under the North American Waterfowl Management Plan (NAWMP) to acquire, protect, restore, and enhance wetlands and other habitats critical to the long-term conservation of breeding, migrating, and wintering waterfowl. A thorough base of scientific information is required to support and evaluate waterfowl populations and habitat management in North America.

WERC Fact Sheet↗
USGS1878

Bulletin of the United States Geological and Geographical Survey of the Territories: Volume IV, Number 3

Table of Contents ART. XXV.----Field-notes on Birds observed in Dakota and Montana along the Forty-ninth Parallel during the seasons of 1873 and 1874. By Dr. Elliott Coues, U.S.A., late Surgeon and Naturalist U.S. Northern Boundary Commission.....545-662 ART. XXVI.----Notes on a Collection of Fishes from the Rio Grande, at Brownsville, Texas-Continued. By D.S. Jordan, M.D......663-668 ART. XXVII.---Preliminary Studies on the North American Pyralidae. I. By A.R. Grote..... 669-706 ART. XXVIII.--Paleontological Papers No.6: Descriptions of New Species of Invertebrate Fossils from the Laramie Group. By C.A. White, M.D......707-720 ART. XXIX.----Paleontological Papers No.7: On the Distribution of Molluscan Species in the Laramie Group. By C. A. White, M.D......721-724 ART. XXX.-----On some Dark Shale recently discovered below the Devonian Limestones, at Independence, Iowa\; with a Notice of its Fossils and Description of New Species. By S. Calvin, Professor of Geology, State University of Iowa.....725-730 ART. XXXI.----On the Mineralogy of Nevada. By W.J. Hoffman, M.D......731-745

Report↗
USGS2012

Tagging age-1 Lost River and shortnose suckers with passive integrated transponders, Upper Klamath Lake, Oregon–Summary of 2009–11 effort

A passive integrated transponder (PIT) tagging study was initiated in 2009 for age-1 endangered Lost River and shortnose suckers in Upper Klamath Lake, Oregon, for the purpose of examining causes of mortality, validating estimated age to maturity, and examining movement patterns. This study, which was done opportunistically in 2009 and 2010, received funding in 2011 for a directed tagging effort. Tags were redetected using an existing infrastructure of remote PIT tag readers and tag scanning surveys at American white pelican and double-crested cormorant breeding and loafing areas. Individual fish histories are used to describe the distance, direction, and timing of age-1 sucker movement. Sucker PIT tag detections in the Sprague and Williamson rivers in mid-summer and in autumn indicate age-1 suckers use these tributaries outside of the known spring spawning season. PIT tags detected in bird habitats indicate predation by birds may have been a cause of mortality in 2009. Field conditions prevented scanning bird breeding and loafing areas in Upper Klamath Wildlife National Refuge for tags in 2011, however, limiting our ability to make inferences about bird predation in those years.

Oregon↗
USGS2004

Comparative habitat use in a juniper woodland bird community

We compared vegetation structure used by 14 bird species during the 1998 and 1999 breeding seasons to determine what habitat features best accounted for habitat division and community organization in Utah juniper (Juniperus osteosperma) woodlands of southwestern Wyoming. Habitat use was quantified by measuring 24 habitat variables in 461 bird-centered quadrats, each 0.04 ha in size. Using discriminant function analysis, we differentiated between habitat used by 14 bird species along 3 habitat dimensions: (1) variation in shrub cover, overstory juniper cover, mature tree density, understory height, and decadent tree density; (2) a gradient composed of elevation and forb cover; and (3) variation in grass cover, tree height, seedling/sapling cover, and bare ground/rock cover. Of 14 species considered, 9 exhibited substantial habitat partitioning: Mourning Dove (Zenaida macroura), Bewick's Wren (Thryomanes bewickii), Blue-gray Gnatcatcher (Polioptila caerulea), Mountain Bluebird (Sialia currucoides), Plumbeous Vireo (Vireo plumbeus), Green-tailed Towhee (Pipilo chlorurus), Brewer's Sparrow (Spizella breweri), Dark-eyed Junco (Junco hyemalis), and Cassin's Finch (Carpodacus cassinii). Our results indicate juniper bird communities of southwestern Wyoming are organized along a 3-dimensional habitat gradient composed of woodland maturity, elevation, and juniper recruitment. Because juniper birds partition habitat along successional and altitudinal gradients, indiscriminate woodland clearing as well as continued fire suppression will alter species composition. Restoration efforts should ensure that all successional stages of juniper woodland are present on the landscape.

Western North American Naturalist↗
USGS2008

Endocrine effects of the herbicide linuron on the American Goldfinch ( Carduelis tristis )

Certain contaminants alter normal physiological function, morphology, and behavior of exposed organisms through an endocrine mechanism. We evaluated how the herbicide linuron, an endocrine-active compound, affects physiological parameters and secondary sex characteristics of the American Goldfinch ( Carduelis tristis ). When administered at relatively low doses (control, 1.0, 4.0, and 16.0 μg linuron per gram of body mass per day), linuron delayed prealternate molt progression in a dose-dependent manner. At the high dose level, linuron exposure lowered hematocrit and female plasma thyroxine concentrations and increased body mass. Neither plasma testosterone concentrations nor the color of plumage or integument of birds in the treatment groups were different from those of the control group. Overall, the physiological effects that were measured suggested disruption of thyroid function. These results highlight the importance of continual monitoring of avian populations for potential effects of exposure to pesticides and other chemicals at sublethal concentrations.

The Auk↗
USGS2018

Monitoring responses to variation in food supply for a migratory waterfowl: American Black Duck (Anas rubripes) in winter

Wintering Black Ducks ( Anas rubripes ) concentrate in wetlands along the Atlantic coast where natural and anthropogenic disturbances have increased over the last 50 years, a period in which the population of Black Ducks has declined. We studied the sensitivity of Black Ducks to perturbations in food supply that often result from disturbances by storms, predators, and people. In the paper, we characterize the responses of captive Black Ducks to shifts in food quality and availability during winter and apply those measures to a comparison of wild birds. Captive ducks that were fed intermittently (3 consecutive days/week) compensated for fasted days to achieve similar body mass and body fat to control birds that were fed every day on both animal- and plant-based diets. However, birds that were fed intermittently expended 15% more energy each day than controls when both groups were fed (536 vs. 464 kJ/kg 0.75 ), which indicates that variable food supply increases the costs of maintenance and thus reduces the number of birds that can be supported on the same resource of food without interruptions to foraging. Egg production was not affected by diet quality provided in spring or by the frequency of feeding during the preceding winter months. Black Ducks lost body fat through winter in captivity and in the wild. Fat stores of birds in New Jersey were greater than those of birds in Maine (13.3 vs. 8.3% of body mass) in January, which reflected the high energy demands of cold temperatures in Maine. Values for ∂ 15 N were greater in Maine than in New Jersey for both red blood cells and plasma, which indicated a consistent diet of marine invertebrates in Maine. Greater isotopic variation in red blood cells indicated that diets were more diverse in New Jersey than in Maine for both ∂ 15 N (9.7 ± 1.1 vs. 11.2 ± 0.4‰) and for ∂ 13 C (− 15.1 ± 2.2 vs. − 13.8 ± 1.4‰). Plasma ∂ 13 C was enriched over red blood cells in wild birds especially those with low fat stores, which suggested birds with low energy stores were shifting diets. Black Ducks can compensate for disturbances in feeding by increasing intakes if they have access to high quality wetlands where they are able to find abundant food. High energy demands at cold temperatures may constrain fat stores and thus the tolerance of feeding disturbances especially at the northern limits of the winter range. We hypothesize that decreasing variation in diet may indicate an increase in vulnerability to disturbance in winter when body fat is low. Recent efforts to assess and improve habitat quality of Black Ducks could be enhanced by monitoring the body composition and diet of birds to assess their vulnerability to disturbances in food supply and energy demands.

Journal of Comparative Physiology B: Biochemical, ↗
USGS2013

Multi-species call-broadcast improved detection of endangered Yuma clapper rail compared to single-species call-broadcast

Broadcasting calls of marsh birds during point-count surveys increases their detection probability and decreases variation in the number of birds detected across replicate surveys. However, multi-species monitoring using call-broadcast may reduce these benefits if birds are reluctant to call once they hear broadcasted calls of other species. We compared a protocol that uses call-broadcast for only one species (Yuma clapper rail [Rallus longirostris yumanensis]) to a protocol that uses call-broadcast for multiple species. We detected more of each of the following species using the multi-species protocol: 25 % more pied-billed grebes, 160 % more American bitterns, 52 % more least bitterns, 388 % more California black rails, 12 % more Yuma clapper rails, 156 % more Virginia rails, 214 % more soras, and 19 % more common gallinules. Moreover, the coefficient of variation was smaller when using the multi-species protocol: 10 % smaller for pied-billed grebes, 38 % smaller for American bitterns, 19 % smaller for least bitterns, 55 % smaller for California black rails, 5 % smaller for Yuma clapper rails, 38 % smaller for Virginia rails, 44 % smaller for soras, and 8 % smaller for common gallinules. Our results suggest that multi-species monitoring approaches may be more effective and more efficient than single-species approaches even when using call-broadcast.

Wetlands↗
USGS2026

Exploring trip preference heterogeneity in away-from-home birdwatchers using a discrete choice experiment

Birdwatching has grown in popularity worldwide and birdwatchers have emerged as an important constituency for wildlife and habitat conservation. To help promote wetland conservation, agencies and managers need to understand birdwatchers' desired trip experiences. We conducted national web-based surveys of American and Canadian birdwatchers by employing a discrete choice experiment to explore birdwatching trip preferences. We also collected information about participation in birdwatching and recreation specialization. We used latent class analysis to identify groups of birdwatchers with similar preferences. Our analysis indicated that birdwatchers were not homogeneous in their preferences. The seven attributes and associated attribute levels that were presented to participants (travel distance, site naturalness, bird rarity, the presence of waterfowl and wetlands, ease of access, species diversity and the number of birds seen) were all relevant, to varying degrees, in decisions about whether to take a birdwatching trip. We identified five latent classes of birdwatchers in the United States and Canada. ‘Nature seekers’ prioritised setting naturalness; ‘local birdwatchers’ strongly preferred shorter travel distances; ‘list-focused birdwatchers’ prioritised bird rarity and diversity; whereas ‘site-focused birdwatchers’ prioritised on-site characteristics above bird-related characteristics; and ‘casual birdwatchers’ were most likely to opt out of taking a trip. We found variation in recreation specialization and avidity levels across all the classes. Some classes ( e.g. list-focused birdwatchers) tend to be more specialised and more avid than others ( e.g. casual and local birdwatchers). Recognising the diversity of birdwatcher trip preferences can help outdoor recreation and wildlife managers provide a variety of suitable settings, services, and experiences.

Journal of Outdoor Recreation and Tourism↗
USGS2002

Influence of topography on density of grassland passerines in pastures

Pastures provide substantial habitat for grassland birds of management concern in the Driftless Area of southwestern Wisconsin. The rolling topography in this region is characterized by lowland valleys surrounded by relatively steep and often wooded slopes which are set apart from more expansive treeless uplands. We hypothesized that there would be lower densities of area sensitive grassland passerines in lowland grasslands compared to upland grasslands because of their preference for larger more open grasslands. To test this hypothesis and assess how well pasture area and vegetation structure predicted grassland passerine density compared to upland/lowland status, we conducted point counts of birds in 60 pastures in May-June 1997 and 1998. Upland pastures generally supported greater densities of grassland passerines than lowland pastures. Densities of Savannah sparrow ( Passerculus sandwichensis ) and bobolink ( Dolichonyx oryzivorus ) were significantly higher in upland pastures than in lowland pastures. Grasshopper sparrow ( Ammodramus savannarum ) density was significantly higher on uplands in one of the study years. The density of eastern meadowlark ( Sturnella magna ), western meadowlark ( S. neglecta ) and sedge wren ( Cistothorus platensis ) did not differ significantly between uplands and lowlands. Grassland passerine density was also predicted by pasture size and vegetation structure. Densities of bobolink and grasshopper sparrow were higher in larger pastures. Bobolink and Savannah sparrow occurred on pastures with greater vegetation height-density and less bare ground; bobolink also preferred shallower litter depths. Lowland pastures supported grassland bird species of management concern and should not be neglected. However, we recommend that pasture management for grassland passerines in areas of variable topography favor relatively large upland pastures that will contain higher densities of species of management concern.

Wisconsin↗
USGS2011

Phylogeography of a vanishing North American songbird: The Painted Bunting (Passerina ciris)

The breeding distribution of Painted Buntings ( Passerina ciris ) is comprised of two allopatric populations separated by a 550-km distributional gap in the southeastern United States. Curiously, the boundary between the two recognized P. ciris subspecies does not separate the two allopatric breeding populations but instead runs roughly through the center of the interior population. Genetic relationships among these subspecies, and the allopatric breeding populations of Painted Bunting, have not been assessed. Given the recent decline in overall abundance of this species, such an assessment is warranted. We sampled birds from 15 localities (138 individuals) and identified 35 distinct haplotypes, six belonging to the Atlantic Coast population and 26 to the interior population, with three shared by both populations. AMOVA results showed that a significantly greater portion of the total genetic variance is explained when grouping birds by the interior and Atlantic Coast populations rather than by subspecies. Furthermore, our data indicate that the Atlantic Coast and interior populations represent independently evolving taxa, with no measureable gene flow between them. Although recently diverged (26,000–115,000 years ago), these isolated bunting populations represent incipient species. For development of conservation strategies, we suggest that the Atlantic Coast and interior populations be recognized as separate management units.

Conservation Genetics↗
USGS2003

Spring bird migration in Mississippi Alluvial Valley forests

We surveyed forest songbirds during migration in bottomland hardwood forest stands and managed cottonwood ( Populus deltoides ) plantations in northeast Louisiana and west-central Mississippi between 24 March and 24 May 1996 and 1997. We detected more bird species in bottomland hardwood stands than in cottonwood stands. Within hardwood stands, we detected more individuals in stands subjected to uneven-aged timber harvest than in unmanaged stands. Early in migration, avian species composition was similar in both forest types, being comprised mainly of short-distance migrants. Bird species composition in these forest types became increasingly disparate as long-distance neotropical-nearctic migrants arrived. Ten bird species were characteristic of bottomland hardwood forests, whereas eight different species were characteristic of managed cottonwood plantations. Because these two forest types supported different bird communities, both forest types provide important inland stopover habitat during migration. Silvicultural management of bottomland hardwood forests that increases their understory vegetation will provide forested habitat for a more species rich and abundant population of songbirds during migration.

American Midland Naturalist↗
USGS2002

Regional fidelity and movement patterns of wintering killdeer in an agricultural landscape

Killdeer ( Charadrius vociferus ) is a common and widespread North American species for which there are few studies of residency patterns and movements. We quantified fidelity and movement patterns of 24 radio-tagged Killdeer in the Willamette Valley of Oregon during the winter of 1999-2000. Results from telemetry surveys and census efforts revealed that the group monitored was composed of winter residents (63%), winter transients (26%), and year-round residents (11%). Movements were localized with birds detected at an average distance of 5.15 ± 0.91 (SE) km from the site of capture. Mean home range size (95% kernel) was 7.73 ± 3.19 km 2 . However, results also indicated periodic exploratory movements, with some birds detected up to 30 km from marking sites. Overall, individuals exhibited a low degree of fidelity to specific sites and were detected at an average of 11.9 ± 1.1 sites. No differences were found in monthly movement patterns. In almost all cases, year-round residents were more sedentary than winter residents and winter transients. Results indicate a complex regional population structure and highlight the need to consider both migrant and resident birds, as well as seasonal differences in habitat needs and space use requirements, in future conservation planning efforts.

Oregon↗
USGS2013

The influence of study species selection on estimates of pesticide exposure in free-ranging birds

Field studies of pesticide effects on birds often utilize indicator species with the purpose 16 of extrapolating to other avian taxa. Little guidance exists for choosing indicator species to 17 monitor the presence and/or effects of contaminants that are labile in the environment or body, 18 but are acutely toxic, such as anticholinesterase (anti-ChE) insecticides. Use of an indicator 19 species that does not represent maximum exposure and/or effects could lead to inaccurate risk 20 estimates. Our objective was to test the relevance of a priori selection of indicator species for a 21 study on pesticide exposure to birds inhabiting fruit orchards. We used total plasma 22 cholinesterase (ChE) activity and ChE reactivation to describe the variability in anti-ChE exposure among avian species in two conventionally managed fruit orchards. Of seven 24 species included in statistical analyses, the less common species, chipping sparrow (Spizella 25 passerina), showed the greatest percentage of exposed individuals and the greatest ChE 26 depression, whereas the two most common species, American robins (Turdus migratorius) and 27 grey catbirds (Dumatella carolinensis), did not show significant exposure. Due to their lower 28 abundance, chipping sparrows would have been an unlikely choice for study. Our results show 29 that selection of indicator species using traditionally accepted criteria such as abundance and 30 ease of collection may not identify species that are at greatest risk. Our efforts also demonstrate 31 the usefulness of conducting multiple-species pilot studies prior to initiating detailed studies on 32 pesticide effects. A study such as ours can help focus research and resources on study species 33 that are most appropriate.

Environmental Management↗