Geology topics

David Smith

Publications and source records attributed to David Smith.

27 records · Page 2Linked to original sources

USGS2011

Demographic consequences of migratory stopover: Linking red knot survival to horseshoe crab spawning abundance

Understanding how events during one period of the annual cycle carry over to affect survival and other fitness components in other periods is essential to understanding migratory bird demography and conservation needs. Previous research has suggested that western Atlantic red knot ( Calidris canutus rufa ) populations are greatly affected by horseshoe crab ( Limulus polyphemus ) egg availability at Delaware Bay stopover sites during their spring northward migration. We present a mass‐based multistate, capture‐recapture/resighting model linking (1) red knot stopover mass gain to horseshoe crab spawning abundance and (2) subsequent apparent annual survival to mass state at the time of departure from the Delaware Bay stopover area. The model and analysis use capture‐recapture/resighting data with over 16,000 individual captures and 13,000 resightings collected in Delaware Bay over a 12 year period from 1997–2008, and the results are used to evaluate the central management hypothesis that red knot populations can be influenced by horseshoe crab harvest regulations as part of a larger adaptive management effort. Model selection statistics showed support for a positive relationship between horseshoe crab spawning abundance during the stopover and the probability of red knots gaining mass (parameter coefficient from the top model b̂ = 1.71, = 0.46). Our analyses also supported the link between red knot mass and apparent annual survival, although average estimates for the two mass classes differed only slightly. The addition of arctic snow depth as a covariate influencing apparent survival improved the fit of the data to the models (parameter coefficient from the top model b̂ = 0.50, = 0.08). Our results indicate that managing horseshoe crab resources in the Delaware Bay has the potential to improve red knot population status.

Delaware, New Jersey↗

USGS2011

Non-native fish control below Glen Canyon Dam - Report from a structured decision-making project

This report describes the results of a structured decision-making project by the U.S. Geological Survey to provide substantive input to the Bureau of Reclamation (Reclamation) for use in the preparation of an Environmental Assessment concerning control of non-native fish below Glen Canyon Dam. A forum was created to allow the diverse cooperating agencies and Tribes to discuss, expand, and articulate their respective values; to develop and evaluate a broad set of potential control alternatives using the best available science; and to define individual preferences of each group on how to manage the inherent trade-offs in this non-native fish control problem. This project consisted of two face-to-face workshops, held in Mesa, Arizona, October 18-20 and November 8-10, 2010. At the first workshop, a diverse set of objectives was discussed, which represented the range of concerns of those agencies and Tribes present. A set of non-native fish control alternatives ('hybrid portfolios') was also developed. Over the 2-week period between the two workshops, four assessment teams worked to evaluate the control alternatives against the array of objectives. At the second workshop, the results of the assessment teams were presented. Multi-criteria decision analysis methods were used to examine the trade-offs inherent in the problem, and allowed the participating agencies and Tribes to express their individual judgments about how those trade-offs should best be managed in Reclamation`s selection of a preferred alternative. A broad array of objectives was identified and defined, and an effort was made to understand how these objectives are likely to be achieved by a variety of strategies. In general, the objectives reflected desired future conditions over 30 years. A rich set of alternative approaches was developed, and the complex structure of those alternatives was documented. Multi-criteria decision analysis methods allowed the evaluation of those alternatives against the array of objectives, with the values of individual agencies and tribes deliberately preserved. Trout removal strategies aimed at the Paria to Badger Rapid reach (PBR), with a variety of permutations in deference to cultural values, and with backup removal at the Little Colorado River reach (LCR) if necessary, were identified as top-ranking portfolios for all agencies and Tribes. These PBR/LCR removal portfolios outperformed LCR-only removal portfolios, for cultural reasons and for effectiveness - the probability of keeping the humpback chub population above a desired threshold was estimated to be higher under the PBR/LCR portfolios than the LCR-only portfolios. The PBR/LCR removal portfolios also outperformed portfolios based on flow manipulations, primarily because of the effect of sport fishery and wilderness recreation objectives, as well as cultural objectives. The preference for the PBR/LCR removal portfolios was quite robust to variation in the objective weights and to uncertainty about the underlying dynamics, at least over the ranges of uncertainty investigated. Examination of the effect of uncertainty on the recommended outcomes allowed us to complete a 'value of information' analysis. The results of this analysis led to an adaptive strategy that includes three possible long-term management actions (no action; LCR removal; or PBR removal) and seeks to reduce uncertainty about the following two issues: the degree to which rainbow trout limit chub populations, and the effectiveness of PBR removal to reduce trout emigration downstream into Marble and eastern Grand Canyons, where the largest population of humpback chub exist. In the face of uncertainty about the effectiveness of PBR removal, a case might be made for including flow manipulations in an adaptive strategy, but formal analysis of this case was not conducted. The full set of conclusions described above is not definitive, however. This analysis described in this report is a simplified depiction of the t

Open-File Report↗

USGS2009

Comparative status and assessment of Limulus polyphemus with emphasis on the New England and Delaware Bay populations

Increases in harvest of the American horseshoe crab ( Limulus polyphemus ) during the 1990s, particularly for whelk bait, coupled with decreases in species that depend on their eggs has reduced horseshoe crab abundance, threatened their ecological relationships, and dictated precautionary management of the horseshoe crab resource. Accordingly, population assessments and monitoring programs have been developed throughout much of the horseshoe crab’s range. We review and discuss implications for several recent assessments of Delaware Bay and New England populations and a meta-analysis of region-specific trends. These assessments show that the western Atlantic distribution of the horseshoe crab is comprised of regional or estuarine-specific meta-populations, which exhibit distinct population dynamics and require management as separate units. Modeling of Delaware Bay and Cape Cod populations confirmed that overharvest caused declines, but indicated that some harvest levels are sustainable and consistent with population growth. Coast-wide harvest was reduced by 70% from 1998 to 2006, with the greatest reductions within Delaware Bay states. Harvest regulations in Delaware Bay starting in the late 1990s, such as harvest quotas, seasonal closures, male-only harvest, voluntary use of bait-saving devices, and establishment of the Carl N. Shuster Jr. Horseshoe Crab Reserve, were followed by stabilization and recent evidence of increase in abundance of horseshoe crabs in the region. However, decreased harvest of the Delaware Bay population has redirected harvest to outlying populations, particularly in New York and New England . While the recent Delaware Bay assessments indicate positive population growth, increased harvest elsewhere is believed to be unsustainable. Two important considerations for future assessments include (1) managing Delaware Bay horseshoe crab populations within a multi-species context, for example, to help support migratory shorebirds and (2) anticipating the potential for harvest restrictions within Delaware Bay to redirect harvest onto outlying populations that cannot sustain the increased harvest.

Book chapter↗

USGS2009

An incomplete analysis

Niles and colleagues (2009) do not present all of the data relevant to the issues they address in the article they wrote for BioScience. They reference unnamed sources for pre-1997 horseshoe crab harvest to conclude that recent harvest exceeds historic harvest. In fact, reported landings from New Jersey, Delaware, Maryland, and Virginia in 2006 (352 metric tons [mt]) were between landings in 1989 (365 mt) and 1990 (232 mt) (www.st.nmfs.noaa.gov/st1/commercial/inaex.html), despite nonmandatory reporting coastwide before 1998 (Kreamer and Michels 2009). They present egg densities from New Jersey beaches only. Of the 11 Delaware beaches sampled, eggs in the top 5 centimeters exceeded their monitoring target of 50,000 per square meter at 5 in 2006 and at 6 in 2007 (Kalasz et al. 2008). They rely on the Delaware trawl survey for historic trends. Nine fishery-independent surveys have been used to assess trends in the Delaware Bay region, and several began before 1990 (Smith et al. 2009a).

BioScience↗

USGS2001

Geologic map of the Saint Joseph area, Missouri and Kansas

This map was prepared as a collaborative effort with the Missouri Division of Geology and Land Survey, the Kansas Geological Survey, and the Nebraska Conservation and Survey Division. Map units and preliminary contacts between units were identified using stereoscopic pairs of high altitude, false color infrared, aerial photographs. Contacts were drawn on twelve USGS 7.5-minute topographic maps, and were checked in the field. U.S. Department of Agriculture Soil Survey maps at a scale of 1:62,500 for Buchanan County, Andrew County, Platte County, and Doniphan County were used to provide a general overview of the soils of the area. A U.S. Geological Survey map at a scale of 1:24,000 showing the geohydrology of Doniphan County, Kansas; soil surveys at a scale of 1:24,000 for Buchanan County, Andrew County, and Platte County; and soil survey at a scale of 1:20,000 for Doniphan were used to corroborate map contacts and field observations.

Kansas, Missouri↗

USGS2000

Relationship of Eastern hemlock ( Tsuga canadensis ) to the ecology of small streams in Delaware Water Gap National Recreation Area

Hemlock ravines in Delaware Water Gap National Recreation Area (DEWA) are highly valued because of their distinctive aesthetic, recreational and ecological qualities. We conducted a comparative study designed to determine the potential long-term consequences to aquatic communities of the suspected transition from hemlock-dominated forests to mixed hardwood forests as a result of hemlock woolly adelgid (HWA; Adelges tsugae) induced mortality. A landscape analysis of DEWA using Geographic Information Systems (GIs) was used to select 14 hemlock and hardwood site-pairs that were similar in topography (i.e., slope, terrain shape, aspect, light levels) and stream size (first or second order) but differed in forest composition. This paired watershed approach provided a powerful means to discern the influence of hemlock forests on stream communities. This study was designed to provide an aquatic perspective on potential losses of biological diversity should hemlock forests die.

New Jersey;Pennsylvania↗

USGS1999

Influence of temperature and substrate on infection rate, triactinomyxon production, and release duration from eastern tubifex worms infected with Myxobolus cerebralis

Salmonid whirling disease is caused by Myxobolus cerebralis , a metazoan parasite with a two host life cycle involving salmonid fish a an aquatic oligochaete, Tubifex tubifex (Wolf, Markiw and Hiltunen, 1986). Whirling disease has been reported in 22 U.S. states with the greatest losses occurring in the salmonid fisheries of western and Midwestern states. Although whirling disease is endemic in the eastern United States, serious documented losses to wild populations have not been reported. Two high priority research needs identified in 1996 were a better understanding of how worm and parasite populations might differ from different geographic areas and how environmental factors affect the various stages of whirling disease. To begin to address these research needs we established "eastern" populations of worms, parasite and fish hosts. This abstract will present data on the effects of temperature and substrate upon eastern T. tubifex worms infected with an eastern isolate of M. cerebralis . The influences of these abiotic factors upon the ability to infect the worms and subsequently their ability to produce waterborne triactinomyxons.

Book↗

USGS1997

A revised annotated checklist of the Chironomidae (Insecta: Diptera) of the southeastern United States

A revised annotated checklist for the chironomid midges (Diptera: Chironomidae) of the southeastern United States is presented that includes the states of Alabama, Florida, Georgia, North Carolina, South Carolina, and Tennessee. Much of the information concerns occurrence and habitat preference records based upon the authors' data, as well as published and unpublished data. Some information is also presented that includes aspects of biology, habitat preference, bibliographic sources, and nomenclatorial changes. Based upon the present work, the chironomid fauna of the southeastern states is comprised of 189 genera (172 described, 17 informally or unofficially described) and 754 species (505 described, 17 informally or unofficially described, 33 that are assumed for generic or subgeneric presence only, 197 estimated species, and 2 species groups). Several new species synonyms and generic placements are recognized. Thirty-eight genera known from the Nearctic region remain unknown from the southeastern states. Diversity of species was greatest in the subfamily Chironominae, considering named as well as unnamed and estimated species. There were no significant changes in overall regional distribution patterns of subfamilies or habitat preferences form that which has been previously reported. The greatest totals for regional records, habitat types, and state occurrences were the Coastal Plain (378), streams (271), and North Carolina (373), respectively.

Transactions of the American Entomological Society↗

USGS1990

Chironomidae of the southeastern United States: a checklist of species and notes on biology, distribution, and habitat

We provide a current listing of the species of midges (Diptera:Chironomidae) in the southeastern United States (Alabama, Florida, Georgia, North Carolina, South Carolina, and Tennessee). This checklist should aid research on this group of insects, which have often proved useful in the assessment of water quality. We document each species' distribution and general habitat and provide the best taxonomic reference to facilitate the identification or description of species in that genus. Changes in nomenclature, unique ecological traits, bibliographic sources, or other items of information are summarized in a paragraph on each genus. Of the 10 sub-families currently recognized in the Chironomidae, 7 occur in the Southeast. The chironomid fauna of the six southeastern States now consist of 164 described genera and 479 described species. In addition we have listed 14 genera and 245 species that are tenatively noted as undescribed.

Fish and Wildlife Research↗