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Terrestrial and Aquatic Ecology Commons

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2003

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Articles 1 - 30 of 59

Full-Text Articles in Terrestrial and Aquatic Ecology

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2002), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne Doughten, Frederick A. Hoffman Dec 2003

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2002), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded and some areas and indicators show continuing degradation. Progress in reducing nutrient inputs has made demonstrable improvements and we expect that continued progress toward nutrient reduction goals, along with appropriate fisheries management and chemical contaminant controls, will result in additional improvements to the Bay. An overall summary of findings for the major VA Bay tributaries (i.e. James, York, and Rappahannock Rivers) is bulleted below while the remainder of this …


Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2002), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne Doughten, Frederick A. Hoffman Dec 2003

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2002), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded and some areas and indicators show continuing degradation. Progress in reducing nutrient inputs has made demonstrable improvements and we expect that continued progress toward nutrient reduction goals, along with appropriate fisheries management and chemical contaminant controls, will result in additional improvements to the Bay. An overall summary of findings for the major VA Bay tributaries (i.e. James, York and Rappahannock Rivers) is bulleted below while the remainder of this …


Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2002), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman Dec 2003

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2002), Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded and some areas and indicators show continuing degradation. Progress in reducing nutrient inputs has made demonstrable improvements and we expect that continued progress toward nutrient reduction goals, along with appropriate fisheries management and chemical contaminant controls, will result in additional improvements to the Bay. An overall summary of findings for the major VA Bay tributaries (i.e. James, York, and Rappahannock Rivers) is bulleted below while the remainder of this …


Antipredator Behavior And Physiology Determine Lestes Species Turnover Along The Pond-Permanence Gradient, Robby Stoks, Mark A. Mcpeek Dec 2003

Antipredator Behavior And Physiology Determine Lestes Species Turnover Along The Pond-Permanence Gradient, Robby Stoks, Mark A. Mcpeek

Dartmouth Scholarship

Identifying key traits that shape trade-offs that restrict species to only a subset of environmental gradients is crucial to understanding and predicting species turnover. Previous field experiments have shown that larvae of Lestes damselfly species segregate along the entire gradient of pond permanence and predator presence and that differential predation risk and life history constraints together shape their distribution. Here, we report laboratory experiments that identify key differences in behavior and physiology among species that structure their distributions along this gradient. The absence of adaptive antipredator behavioral responses against large dragonfly larvae and fish of Lestes dryas, the only species …


A Case For Taxonomic Recognition Of The Taxon Enodia Anthedon Borealis A. H. Clark (Satyridae), Alex Grkovich, Harry Pavulaan Nov 2003

A Case For Taxonomic Recognition Of The Taxon Enodia Anthedon Borealis A. H. Clark (Satyridae), Alex Grkovich, Harry Pavulaan

The Taxonomic Report of the International Lepidoptera Survey

Clark (1936) described the taxa anthedon and borealis both as new subspecies of Enodia portlandia (Fabricius, 1781). Clark described borealis as the northernmost phenotypically different taxon in this group. Anthedon later became recognized as a distinct species with borealis as a subspecies of it. Masters (1971) characterized E. anthedon borealis as displaying several subtle phenotypic differences from nominotypical anthedon and also noted significant differences in behavior and habitat and reinforced the continued recognition of borealis as a valid subspecies. However, a number of publications after 1971 generally failed to recognize subspecific status for borealis, either ignoring borealis entirely …


A Taxonomic Review Of Chlosyne Ismeria With Description Of A New Subspecies From The Southern Appalachian Mountains, Ronald R. Gatrelle Nov 2003

A Taxonomic Review Of Chlosyne Ismeria With Description Of A New Subspecies From The Southern Appalachian Mountains, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

The taxon Boisduval and Le Conte described in 1833 as Melitaea ismeria is examined as a historical entity and confirmed as a sister subspecies of the taxon Chlosyne ismeria nycteis. The ismeria populations in the southern Appalachian mountains (United States) are described as a new subspecies: Chlosyne ismeria obsoleta. In facies, this new subspecies is most similar to the western subspecies Chlosyne ismeria drusius in that it is dark and contrasting in its dorsal markings. It is known to range from the mountain region of extreme northern Georgia north in the Appalachians to near southwestern Virginia, United States. …


Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2002), Daniel M. Dauer Nov 2003

Benthic Biological Monitoring Program Of The Elizabeth River Watershed (2002), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

A study of the macrobenthic communities of the Elizabeth River watershed was initiated in summer 1999. This report presents the data from the fourth year of sampling in 2002. The three objectives of the Benthic Biological Monitoring Program of the Elizabeth River watershed are: (1) To characterize the health of the tidal waters of the Elizabeth River watershed as indicated by the structure of the benthic communities. ( 2) To conduct trend analyses on long-term data at 14 fixed-point stations to relate temporal trends in the benthic communities to changes in water and/or sediment quality. Trend analyses will …


University Of Nebraska-Lincoln School Of Natural Resources Review: Final Report, December 2003, Michael O'Neill, Phaedra Budy, Stephen Degloria, Ed Kanemasu, Jamie Robertson, Derrel Martin, Anne K. Vidaver, Tylr Naprstek, Donna Woudenberg Nov 2003

University Of Nebraska-Lincoln School Of Natural Resources Review: Final Report, December 2003, Michael O'Neill, Phaedra Budy, Stephen Degloria, Ed Kanemasu, Jamie Robertson, Derrel Martin, Anne K. Vidaver, Tylr Naprstek, Donna Woudenberg

School of Natural Resources: Documents and Reviews

In July 2003, the School of Natural Resource Sciences was merged with the Conservation and Survey Division and the Water Center Nebraska State Survey. This merger produced the School of Natural Resources (hereafter referred to as the "School") in its current form. The University of Nebraska-Lincoln requested a ten-year review of the School's programs and activities. The review was administered by the Cooperative State Research, Education and Extension Service (CSREES) in cooperation with the University of Nebraska-Lincoln's Institute of Agriculture and Natural Resources, the College of Agriculture, and the School.

The review document is divided into nine sections. The first …


Decision Process For Identification Of Estuarine Benthic Impairments, Roberto J. Llansó, Jon H. Volstad, Daniel M. Dauer Nov 2003

Decision Process For Identification Of Estuarine Benthic Impairments, Roberto J. Llansó, Jon H. Volstad, Daniel M. Dauer

Benthic Applications

To meet the requirements of the Clean Water Act, the States of Maryland and Virginia are in the process of developing biological criteria for evaluating estuarine waters. The Chesapeake Bay Benthic Index of Biotic Integrity (B-IBI) is the basis for these biological criteria. As an initial step, a Workgroup developed an interim framework for the application of the B-IBI to the States’ water quality inventory report (305b report) and list of impaired waters (303d list). The Workgroup included representatives of the Maryland Department of the Environment (MDE), Maryland Department of Natural Resources (MDNR), Virginia Department of Environmental Quality (DEQ), USEPA …


Fall 2003, Nsu Oceanographic Center Oct 2003

Fall 2003, Nsu Oceanographic Center

Currents

No abstract provided.


Feeding Responses Of Juvenile And Adult Streblospio Benedicti Webster (Spionidae) To Organic Chemicals Bound To Glass Microbeads, Heidi Kathryn Mahon Oct 2003

Feeding Responses Of Juvenile And Adult Streblospio Benedicti Webster (Spionidae) To Organic Chemicals Bound To Glass Microbeads, Heidi Kathryn Mahon

Biological Sciences Theses & Dissertations

Spionid polychaetes feed at the sediment-water interface using a pair of ciliated palps. Polychaetes select food particles based upon characteristics including size, texture, specific gravity and organic coatings. Juvenile and adult spionids have different stable isotopic carbon signals, indicating the potential to differentiate organic cues ontogenetically. In the present study, the feeding responses of juvenile and adult Streblospio benedicti Webster to seven organic coatings bound (five amino acids and two carbohydrates) to glass microbeads were tested. Juveniles and adults were highly selective for all seven types of organically coated beads. Juveniles were highly selective for threonine; whereas adults were highly …


Csrees School Of Natural Resources Comprehensive Five-Year Review Sep 2003

Csrees School Of Natural Resources Comprehensive Five-Year Review

School of Natural Resources: Documents and Reviews

No abstract provided.


Effects Of Management Practices On Grassland Birds: Greater Prairie-Chicken, W. D. Svedarsky, J. E. Toepfer, R. L. Westemeier, R. J. Robel Sep 2003

Effects Of Management Practices On Grassland Birds: Greater Prairie-Chicken, W. D. Svedarsky, J. E. Toepfer, R. L. Westemeier, R. J. Robel

United States Geological Survey: Effects of Management Practices on Grassland Birds

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 5,500 published and unpublished papers. A range map is provided to indicate the breeding distribution of Greater Prairie-Chicken in the United States and southern Canada. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental …


Summer 2003, Nsu Oceanographic Center Aug 2003

Summer 2003, Nsu Oceanographic Center

Currents

No abstract provided.


A Subspecific Assessment Of The Genus Hesperia (Hesperiinae) In Eastern North America (Part I: The South): New Subspecies Of Hesperia Metea, Hesperia Sassacus And Hesperia Meskei, Ronald R. Gatrelle, Marc C. Minno, Alex Grkovish Jul 2003

A Subspecific Assessment Of The Genus Hesperia (Hesperiinae) In Eastern North America (Part I: The South): New Subspecies Of Hesperia Metea, Hesperia Sassacus And Hesperia Meskei, Ronald R. Gatrelle, Marc C. Minno, Alex Grkovish

The Taxonomic Report of the International Lepidoptera Survey

Hesperia meskei pinocayo Gatrelle and Minno is described from Big Pine Key, Monroe County, Florida, United States. This subspecies is thought to be nearly extinct. Its mainland status is uncertain. It is characterized by bi-colored ventral hindwings with more prominent ventral hindwing spots. Hesperia metea intermedia Gatrelle is described from Pickens County, South Carolina, United States. Its range is from northwestern South Carolina, United States west through Mississippi, United States and probably into Missouri, United States. Males have the least dorsal fulvous of the metea subspecies; ventrally they are well marked. Females are similar to subspecies licinus. Hesperia sassacus …


Fisheries Occasional Publication No. 8 - Department Of Fisheries Stakeholder Survey 2002, Tara Baharthah, Neil R. Sumner Jul 2003

Fisheries Occasional Publication No. 8 - Department Of Fisheries Stakeholder Survey 2002, Tara Baharthah, Neil R. Sumner

Fisheries Occasional Publications

A telephone survey of Department of Fisheries' stakeholders was conducted in November 2002 in order to evaluate their perception of the Department's management of commercial and recreational fishing, pearling and aquaculture, and fish and fish habitat protection. The survey also assessed satisfaction with the level of service provided to stakeholders and their involvement in the decision making process.

The sample comprised of 149 interviews - 40 representing the commercial fishing sector, 40 representing the recreational fishing sector, 40 representing fish and fish habitat protection, and 29 representing aquaculture and pearling.

In general, the stakeholders gave positive responses regarding the Department …


Fisheries Research Contract Report No. 2 - Towards An Assessment Of Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands (Phase 1 : Data Consolidation And Scoping - Final Report For Frdc Project 2000/1 66), C. F. Chubb, K. Nardi Jul 2003

Fisheries Research Contract Report No. 2 - Towards An Assessment Of Natural And Human Use Impacts On The Marine Environment Of The Abrolhos Islands (Phase 1 : Data Consolidation And Scoping - Final Report For Frdc Project 2000/1 66), C. F. Chubb, K. Nardi

Fisheries Research Contract Reports

This project has drawn together existing research data relating to natural and human impacts on the Abrolhos Islands marine habitats. It has surveyed current uses of these habitats and placed anthropogenic impacts within the context of natural perturbations. Through public forum presentation and debate, this work has allowed real issues, not perceptions, to surface and be addressed properly. This was achieved by defining a strategic programme of research through a scientific workshop process involving all community stakeholders. A two volume Fisheries Research Report (WA) summarizes current knowledge and details the workshop proceedings and strategic research plan.


Effect Of Food Availability On Reproduction And Brood Size In A Freshwater Brooding Bivalve, Mark Beekey, Ronald H. Karlson Jul 2003

Effect Of Food Availability On Reproduction And Brood Size In A Freshwater Brooding Bivalve, Mark Beekey, Ronald H. Karlson

Biology Faculty Publications

Brood size is often constrained by the amount of energy available to produce offspring. Yet, energetic constraints may not be as important if the physical capacity to brood offspring is limited. Investigating the relative importance of energetic and physical constraints on brood size is necessary to understand how reproductive strategies are molded by natural selection. We investigated how food availability affects brood size in Sphaerium striatinum, a freshwater bivalve. We reared juveniles to adulthood under three food levels in a common garden experiment. The number of reproductive attempts, brood size, and stage of offspring development were measured. Clams reared …


The Invasion Of The Exotic Cladoceran Daphnia Lumholtzi To Willard Bay Utah: Alterations Of The Pelagic Food Web., Olivia Lester May 2003

The Invasion Of The Exotic Cladoceran Daphnia Lumholtzi To Willard Bay Utah: Alterations Of The Pelagic Food Web., Olivia Lester

Undergraduate Honors Capstone Projects

Willard Bay, a freshwater impoundment of one of the arms of the Great Salt Lake, is shallow, with a mean volume of 9,900 acres and a maximum summer depth of six meters. This reservoir is highly productive, with a mean secchi depth of 4 meters and chlorophyll a concentrations peaking in summer at 9 micrograms per liter.


The Distribution Of Macroinvertebrates In The Schoolcraft/Mississippi River-Lake System, Sarah Roley Apr 2003

The Distribution Of Macroinvertebrates In The Schoolcraft/Mississippi River-Lake System, Sarah Roley

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.


Agroecosystems Analysis From The Grass Roots: A Multidimensional Experiential Learning Course, Mary Wiedenhoeft, Steve Simmons, Ricardo Salvador, Gina Mcandrews, Charles A. Francis, James W. King, David Hole Apr 2003

Agroecosystems Analysis From The Grass Roots: A Multidimensional Experiential Learning Course, Mary Wiedenhoeft, Steve Simmons, Ricardo Salvador, Gina Mcandrews, Charles A. Francis, James W. King, David Hole

Department of Agricultural Leadership, Education, and Communication: Faculty Publications

An intensive, experiential travel course in Agroecosystems Analysis was conducted in Iowa, Minnesota, and Nebraska (United States) during summers of 1998 and 1999. The intended student audience was advanced undergraduate and beginning graduate students. Pretravel readings and a week-long series of farm visits, which consisted of in-depth interviews with the farmers and their families, prepared student teams to analyze and evaluate the production, economic, environmental, and social sustainability of 10 farms. Students shared their analyses both orally and in written reports. Based on a multifaceted student evaluation process, we found that participants were highly motivated, strongly engaged with the course …


Spring 2003, Nsu Oceanographic Center Apr 2003

Spring 2003, Nsu Oceanographic Center

Currents

No abstract provided.


Butterflies Of The North Okanagan, British Columbia, Canada, David L. Threatful Apr 2003

Butterflies Of The North Okanagan, British Columbia, Canada, David L. Threatful

The Taxonomic Report of the International Lepidoptera Survey

An annotated list of 106 species of butterflies known to occur in the north Okanagan area of British Columbia, Canada is presented. Information is provided on flight phenology, elevation and habitat for each species. Field work over the past 100 years shows that this is one of the premiere areas in Canada for butterfly species diversity. More than one third of all known Canadian butterflies have been found in this small area.


Male Reproductive Dynamics In The Caribbean Spiny Lobster Panulirus Argus, Jamie S. Heisig Apr 2003

Male Reproductive Dynamics In The Caribbean Spiny Lobster Panulirus Argus, Jamie S. Heisig

Biological Sciences Theses & Dissertations

The population size structure of the Caribbean Spiny Lobster, Panulirus argus, in the Florida Keys, Florida (USA) has undergone a dramatic shift as a result of fishing pressure on the large individuals of the population. Male lobsters are affected most by fishing because of sexual dimorphism in size and other studies have shown that male size has direct impacts on reproductive output (i.e., number of fertilized eggs/clutch) that are independent of female size. To assess more precisely the impact of male size on fertilization success, I conducted laboratory experiments and field observations to examine various male reproductive attributes over …


Fixation Of Type Locality For Lycaena Acmon Westwood And Characterization Of The Species And Its Distribution, Paul A. Opler Mar 2003

Fixation Of Type Locality For Lycaena Acmon Westwood And Characterization Of The Species And Its Distribution, Paul A. Opler

The Taxonomic Report of the International Lepidoptera Survey

Lycaena acmon Westwood, 1852 is based on a painting and plate legend in Westwood and Hewitson’s Genera of Diurnal Lepidoptera. The specimen illustrated was located in the British Museum Natural History and is the holotype by monotypy. The accompanying plate legend gives “California” as the type locality. Because the butterfly is a member of a complex of species, now considered in the genus Plebejus (Opler and Warren, 2003), that requires much systematic study, and some confusion exists on the identity of L. acmon, it is necessary to fix a more specific type locality, to characterize the species, …


Ecology Of The Missouri River: Missouri River Creel Survey, Bellevue Bridge To Camp Creek, 30 March Through 11 October 2002. Supplement I, Gerald Mestl Mar 2003

Ecology Of The Missouri River: Missouri River Creel Survey, Bellevue Bridge To Camp Creek, 30 March Through 11 October 2002. Supplement I, Gerald Mestl

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This report describes Missouri River activities and results related to a channelized Missouri River creel survey conducted from 30 March through 11 October 2002. This is the third of a planned annual creel survey to be conducted on alternating sections of the channelized Missouri River to measure changes in recreational fishing activity, especially those changes due to large scale habitat restoration efforts. Future reports will contain additional analyses of these data. Anglers spent over 42,000 hours fishing the Missouri River from Bellevue (rkm 967.7) to Camp Creek (rkm 883.5) during the survey period. Effort was steady from late spring (4/27 …


Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane Feb 2003

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: James River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane

Status and Trends for Virginia Chesapeake Bay

This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …


Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane Feb 2003

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: Rappahannock River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane

Status and Trends for Virginia Chesapeake Bay

This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …


Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane Feb 2003

Status And Trends In Water Quality And Living Resources In The Virginia Chesapeake Bay: York River (1985-2001), Daniel M. Dauer, Harold G. Marshall, Kent E. Carpenter, John R. Donat, Michael F. Lane

Status and Trends for Virginia Chesapeake Bay

This summary includes materials provided by Rick Hoffman of the Chesapeake Bay Program of the Virginia Department of Environmental Quality. Environmental information regarding other important conditions in Chesapeake Bay (e.g. submerged aquatic vegetation, fisheries, chemical contaminants) has been reported previously (Chesapeake Bay and its Tributaries: Results of Monitoring Programs And Status of Resources; 2002 Biennial Report of the Secretary of Natural Resources to The Virginia General Assembly).

The Virginia Chesapeake Bay and its tidal tributaries continue to show some environmental trends indicating progress toward restoration of a more balanced and healthy ecosystem. However, the Bay system remains degraded …


Mechanisms Promoting Upriver Transport Of Two Species Of Larval Fish In The Hudson River Estuary (Usa), Eric T. Schultz, Kamazima M M Lwiza, Megan C. Fencil, Jennifer M. Martin Jan 2003

Mechanisms Promoting Upriver Transport Of Two Species Of Larval Fish In The Hudson River Estuary (Usa), Eric T. Schultz, Kamazima M M Lwiza, Megan C. Fencil, Jennifer M. Martin

EEB Articles

Bay anchovy Anchoa mitchilli and naked goby Gobiosoma bosc larvae have been reported to move up-estuary. In the present study, we examined depth preferences and periodic vertical movements that might promote such along-estuary transport in these 2 species. We conducted 2 cruises of 3 d each in the Hudson River estuary, USA. The cruises were 1 wk apart, coinciding with spring and neap tides. We sampled every 2 h with an ichthyoplankton trawl to permit tests of time, depth, and lateral position on larval concentration. We also collected data on water-column structure with a CTD, and current velocity with an …