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What Are You Doing Here? Unexpected Occurrences Of Knobfin Sculpins (Cottus Immaculatus) In Connecticut, Joshua M. Tellier, Brooke Winsmann, Michael Humphreys, Stella Minoudi, Alexandros Triantafyllidis, Eric T. Schultz Jan 2023

What Are You Doing Here? Unexpected Occurrences Of Knobfin Sculpins (Cottus Immaculatus) In Connecticut, Joshua M. Tellier, Brooke Winsmann, Michael Humphreys, Stella Minoudi, Alexandros Triantafyllidis, Eric T. Schultz

EEB Articles

Reductions in cold-water habitat owing to anthropogenic stressors are focusing attention on indicator fish species. We investigated an apparent range expansion in Connecticut of a native cold-water fish, Slimy Sculpin (Cottus cognatus). Unexpectedly, genetic and morphological analyses identified the new population as a non-native cottid from the Ozark region, the Knobfin Sculpin (C. immaculatus). This is the first record of C. immaculatus outside of its native range. The new occurrences were not recognized for over a decade despite comprehensive watershed inventories by state natural resource managers. The mechanism by which the non-native Knobfin Sculpin first arrived in Connecticut is currently …


Halodash: The Deep And Shallow History Of Aquatic Life's Passages Between Marine And Freshwater Habitats, Eric T. Schultz, Lisa Park Boush May 2022

Halodash: The Deep And Shallow History Of Aquatic Life's Passages Between Marine And Freshwater Habitats, Eric T. Schultz, Lisa Park Boush

EEB Articles

This series of papers highlights research into how biological exchanges between salty and freshwater habitats have transformed the biosphere. Life in the ocean and in freshwaters have long been intertwined; multiple major branches of the tree of life originated in the oceans and then adapted to and diversified in freshwaters. Similar exchanges continue to this day, including some species that continually migrate between marine and fresh waters. The series addresses key themes of transitions, transformations, and current threats with a series of questions: When did major colonizations of fresh waters happen? What physiographic changes facilitated transitions? What organismal characteristics facilitate …


Repeated Targets Of Natural Selection During Ecological Transitions Of Fish Across Salinity Boundaries, Jonathan P. Velotta, Stephen D. Mccormick, Andrew Whitehead, Catherine S. Durso, Eric T. Schultz May 2022

Repeated Targets Of Natural Selection During Ecological Transitions Of Fish Across Salinity Boundaries, Jonathan P. Velotta, Stephen D. Mccormick, Andrew Whitehead, Catherine S. Durso, Eric T. Schultz

EEB Articles

Ecological transitions across salinity boundaries have led to some of the most important diversification events in the animal kingdom, especially among fishes. Adaptations accompanying such transitions include changes in morphology, diet, whole-organism performance, and osmoregulatory function, which may be particularly prominent since divergent salinity regimes make opposing demands on systems that maintain ion and water balance. Research in the last decade has focused on the genetic targets underlying such adaptations, most notably by comparing populations of species that are distributed across salinity boundaries. Here, we synthesize research on the targets of natural selection using whole-genome approaches, with a particular emphasis …


Mark-Recapture Study And Habitat Assessment For The Northern Metalmark Butterfly, Calephelis Borealis (Lepidoptera: Riodinidae), Weston J. Henry, Kristian S. Omland, Henry Frye, Wagner L. David Feb 2022

Mark-Recapture Study And Habitat Assessment For The Northern Metalmark Butterfly, Calephelis Borealis (Lepidoptera: Riodinidae), Weston J. Henry, Kristian S. Omland, Henry Frye, Wagner L. David

EEB Articles

Background: The northern metalmark (Calephelis borealis), is an exceedingly local, globally rare butterfly that is declining across the Midwestern and Northeastern USA. The principal stressors driving colony losses include afforestation and invasive plants that crowd out its larval hostplant (Packera ovata) and nectar resources.

Aims/Methods: To better understand its declines and guide restoration efforts, we 1) performed a mark-recapture study in Connecticut to document population trends where we were actively managing vegetation; 2) conducted a range-wide survey for evidence of phylogeographic structure, using cytochrome oxidase (CO1); 3) investigated abundance determinants of its larval foodplant, Packera ovata …


Seasonal Reproductive Allocation In Landlocked Alewife Alosa Pseudoharengus, In The Context Of Niche Construction And Eco-Evolutionary Feedbacks, Foivos Mouchlianitis, Eric T. Schultz, Kostas Ganias Jan 2022

Seasonal Reproductive Allocation In Landlocked Alewife Alosa Pseudoharengus, In The Context Of Niche Construction And Eco-Evolutionary Feedbacks, Foivos Mouchlianitis, Eric T. Schultz, Kostas Ganias

EEB Articles

The bidirectional dynamics between species and their biotic and abiotic environments, known as eco-evolutionary feedbacks, may shift the direction of evolution and alter the ecological role of species. Alewife, Alosa pseudoharengus, is an exemplary species to study reciprocal feedbacks between ecology and evolution, owing to repeated independent derivations of a landlocked life history from an ancestral anadromous form. In this study we analysed the reproductive allocation during the spawning season in a landlocked Alewife population in the context of eco-evolutionary feedbacks. We also compared our findings with previous results from a neighbouring anadromous population of the species. Similarities were found …


Stomach Contents And Stable Isotope Analysis Reveal Ontogenetic Shifts And Spatial Variability In Brama Australis Diet, Sebastian A. Klarian, Eric T. Schultz, María Francisca Hernández, Juan Antonio Valdes, Francisco Fernandoy, Mónica Barros, Sergio Neira, Hugo Arancibia Jan 2022

Stomach Contents And Stable Isotope Analysis Reveal Ontogenetic Shifts And Spatial Variability In Brama Australis Diet, Sebastian A. Klarian, Eric T. Schultz, María Francisca Hernández, Juan Antonio Valdes, Francisco Fernandoy, Mónica Barros, Sergio Neira, Hugo Arancibia

EEB Articles

Many marine fisheries rely on production and energy flow in the pelagic zone, thus sustainable management of exploited pelagic fishes benefits from insight into temporal, spatial and ontogenetic variability in the trophic ecology of these species. Here we analyze stomach contents and stable isotopes to reveal spatial variability (focusing on two fishing grounds, north and south of an oceanographic barrier in the Pacific Ocean) and ontogenetic changes (contrasting immature and mature) in Southern Ray’s Bream (Brama australis) diet composition in Chilean waters. Stomach contents analysis indicated that euphausiids were predominant components of the diet in both fishing grounds and ontogenetic …


Discovery Of Epiphytic Lichens In Connecticut Suggests Novel Introduction And Reintroduction Via Horticultural Practices, Henry A. Frye, Zachary Muscavitch, Bernard Goffinet Apr 2021

Discovery Of Epiphytic Lichens In Connecticut Suggests Novel Introduction And Reintroduction Via Horticultural Practices, Henry A. Frye, Zachary Muscavitch, Bernard Goffinet

EEB Articles

The discovery of Teloschistes chrysophthalmus in Connecticut more than one hundred years since its last known occurrence is argued to result from human introduction. The species only occurred on the horticultural tree, Gleditsia triacanthos var. inermis, planted on the University of Connecticut campus. Gleditsia triacanthos is not indigenous to northeastern North America, but is widespread in the central United States. Other epiphytic macrolichens also recorded on this phorophyte include Punctelia bolliana and Parmotrema austrosinense, both widespread in the central United States, and new to Connecticut and New England, respectively. This is likely the first reported case of combined …


Ovarian Dynamics And Fecundity Regulation In Blueback Herring, Alosa Aestivalis, From The Connecticut River, Us, Foivos Alexandros Mouchlianitis, Eric T. Schultz, Thassya C. Dos Santos Schmidt, Justin P. Davis, Kostas Ganias Jan 2021

Ovarian Dynamics And Fecundity Regulation In Blueback Herring, Alosa Aestivalis, From The Connecticut River, Us, Foivos Alexandros Mouchlianitis, Eric T. Schultz, Thassya C. Dos Santos Schmidt, Justin P. Davis, Kostas Ganias

EEB Articles

We analyzed ovarian dynamics of anadromous blueback herring, Alosa aestivalis, in Connecticut River with the principal aim of exploring oocyte recruitment and how it shapes the fecundity pattern. We examined the oocyte release strategy and analyzed spawning cyclicity by linking oocyte growth to the degeneration of postovulatory follicles. Females were accordingly classified as pre-spawners, early and late active spawners, and oocyte recruitment intensity was compared among the different spawning phases. Oocyte recruitment occurred continuously and in parallel with spawning activity, a pattern which is diagnostic of indeterminate fecundity. However, both fecundity and oocyte recruitment intensity progressively decreased (tapered) throughout …


A Synergism Between Dimethyl Trisulfide And Methyl Thiolacetate In Attracting Carrion-Frequenting Beetles Demonstrated By Use Of A Chemically-Supplemented Minimal Trap, Stephen T. Trumbo, John Dicapua Iii Jan 2020

A Synergism Between Dimethyl Trisulfide And Methyl Thiolacetate In Attracting Carrion-Frequenting Beetles Demonstrated By Use Of A Chemically-Supplemented Minimal Trap, Stephen T. Trumbo, John Dicapua Iii

EEB Articles

Volatile organic compounds derived from microbes recruit insects to carrion, shaping community assembly and ecological succession. The importance of individual volatiles and interactions between volatiles are difficult to assess in the field because of (1) the myriad compounds from decomposing animals, and (2) the likelihood that complex component blends are important for the final approach to carrion. On the assumption that searching insects may use simpler volatile cues to orient at a distance, we employed a chemically-supplemented minimal trap that uses test chemicals to attract from a distance and a minimal carrion bait to induce trap entry. Traps supplemented with …


Using Harvest Slot Limits To Promote Stock Recovery And Broaden Age Structure In Marine Recreational Fisheries: A Case Study, Jacob M. Kasper, Jeffrey Brust, Amanda Caskenette, Jason Mcnamee, Jason C. Vokoun, Eric T. Schultz Jan 2020

Using Harvest Slot Limits To Promote Stock Recovery And Broaden Age Structure In Marine Recreational Fisheries: A Case Study, Jacob M. Kasper, Jeffrey Brust, Amanda Caskenette, Jason Mcnamee, Jason C. Vokoun, Eric T. Schultz

EEB Articles

Fish populations with broad age distributions are expected to have higher reproductive capacity than age-truncated populations because of the disproportionate contributions of older fish. Harvest slot limits, an expected means of ameliorating age truncation, are modeled for Tautog Tautoga onitis in an overfished population subunit that is experiencing overfishing. Tautog, currently managed by a 40 cm minimum size limit (MSL), is a candidate species for slots because it is relatively long-lived, slow-growing, with low discard mortality. We evaluated changes in biomass and abundance-at-age relative to management with the current MSL regulations using a forward population simulation model for four slots: …


Bio-Economic Outcomes Under Alternative Management Strategies With Human Choice And Behavior: Modeling Tautog And Anglers' Preferences, Eric T. Schultz, Zhenshan Chen, Pengfei Liu, Stephen Swallow, Jacob M. Kasper Jan 2020

Bio-Economic Outcomes Under Alternative Management Strategies With Human Choice And Behavior: Modeling Tautog And Anglers' Preferences, Eric T. Schultz, Zhenshan Chen, Pengfei Liu, Stephen Swallow, Jacob M. Kasper

EEB Articles

Key findings

  • There was relatively strong support for slot limits, and roughly comparable support for status quo management, among anglers fishing for Tautog in Long Island Sound.
  • Respondents were not in favor of a total moratorium on fishing for Tautog.
  • Providing survey respondents information on how different management scenarios will affect fishing in the future had little detectable impact on fishing preferences.
  • Respondents expected to fish less in the future if a wide slot limit is imposed or if status quo management is maintained, but expected no change in effort if a narrow slot limit is imposed.
  • Changes in regulations …


Comparison Of Skull Size In Sympatric And Allopatric Fishers (Martes Pennanti) And American Martens (Martes Americana), Matthew Brandt, Miranda Davis, Tom Harrington, Eric Schultz Mar 2019

Comparison Of Skull Size In Sympatric And Allopatric Fishers (Martes Pennanti) And American Martens (Martes Americana), Matthew Brandt, Miranda Davis, Tom Harrington, Eric Schultz

EEB Articles

Interactions between two species with similar ranges may cause character displacement, especially if the two species are closely related. There is little research regarding character displacement between two related mammal species. American martens (Martes americana) and fishers (M. pennanti) are closely related and have some range overlap. I hypothesized that American martens would be smaller in size in locations where they are sympatric to fishers compared to allopatric locations. Also, I hypothesized that fishers would be larger in sympatric locations compared to their allopatric counterparts. To test these hypotheses, I compared the skull sizes of American …


Developing An Environmentally And Economically Sustainable Sugar Kelp Aquaculture Industry In Southern New England: From Seed To Market, Charles Yarish, Jang Kyun Kim, Scott Lindell, Hauke Kite-Powell Nov 2017

Developing An Environmentally And Economically Sustainable Sugar Kelp Aquaculture Industry In Southern New England: From Seed To Market, Charles Yarish, Jang Kyun Kim, Scott Lindell, Hauke Kite-Powell

EEB Articles

The long-term goal of this proposed project was to promote development of a sustainable sugar kelp industry that can help revitalize working waterfronts, and increase employment and economic opportunities for seafood production, processing, and distribution services in Southern New England and New York. To achieve this goal, we have transfer cultivation techniques of Saccharina latissima (sugar kelp) from academic laboratories to commercially viable farms, introduce processing techniques, and provide templates for business plans. An additional benefit of this study are the ecosystem services afforded by sugar kelp farming. Kelp aquaculture will remove carbon and nitrogen (as well as phosphorus) from …


Zebra Mussel (Dreissena Polymorpha) Affects The Feeding Ecology Of Early Stage Striped Bass (Morone Saxatilis) In The Hudson River Estuary, Michael G. Smircich, David L. Strayer, Eric T. Schultz Jan 2016

Zebra Mussel (Dreissena Polymorpha) Affects The Feeding Ecology Of Early Stage Striped Bass (Morone Saxatilis) In The Hudson River Estuary, Michael G. Smircich, David L. Strayer, Eric T. Schultz

EEB Articles

Variability in the feeding ecology of young fishes over short and long time scales in estuaries is likely to affect population dynamics. We studied 14 years of early stage Striped Bass feeding ecology in the Hudson River Estuary over a 25-year time span, including years in which invasive zebra mussels markedly altered energy flow within the estuary. We predicted that feeding success would be low and that diet composition would be altered during years of high zebra mussel impact, particularly in upriver locations where mussels occur. Feeding success in the short term was indicated by volume of gut contents and …


Direct And Indirect Selection On Floral Pigmentation By Pollinators And Seed Predators In A Color Polymorphic South African Shrub, Jane E. Carlson, Kent E. Holsinger Jan 2013

Direct And Indirect Selection On Floral Pigmentation By Pollinators And Seed Predators In A Color Polymorphic South African Shrub, Jane E. Carlson, Kent E. Holsinger

EEB Articles

The coexistence of different color morphs is often attributed to variable selection pressures across space, time, morph frequencies or selection agents, but the routes by which each morph is favored are rarely identified. In this study we untangle the interactions and trait pleiotropisms that influence floral color polymorphisms on a local scale in Protea, within which ~40% of species are polymorphic. Previous work shows that seed predators and reproductive differences likely influence polymorphism maintenance in four Protea species. Here, we explore whether selection acts on floral color directly or indirectly in Protea aurea, using path analysis of pollinator …


Euryhalinity In An Evolutionary Context, Eric T. Schultz, Stephen D. Mccormick Jan 2013

Euryhalinity In An Evolutionary Context, Eric T. Schultz, Stephen D. Mccormick

EEB Articles

This chapter focuses on the evolutionary importance and taxonomic distribution of euryhalinity. Euryhalinity refers to broad halotolerance and broad halohabitat distribution. Salinity exposure experiments have demonstrated that species vary tenfold in their range of tolerable salinity levels, primarily because of differences in upper limits. Halotolerance breadth varies with the species’ evolutionary history, as represented by its ordinal classification, and with the species’ halohabitat. Freshwater and seawater species tolerate brackish water; their empirically-determined fundamental haloniche is broader than their realized haloniche, as revealed by the halohabitats they occupy. With respect to halohabitat distribution, a minority of species (<10%) are euryhaline. Habitat-euryhalinity is prevalent among basal actinopterygian fishes, is largely absent from orders arising from intermediate nodes, and reappears in the most derived taxa. There is pronounced family-level variability in the tendency to be halohabitat-euryhaline, which may have arisen during a burst of diversification following the Cretaceous-Palaeogene extinction. Low prevalence notwithstanding, euryhaline species are potent sources of evolutionary diversity. Euryhalinity is regarded as a key innovation trait whose evolution enables exploitation of new adaptive zone, triggering cladogenesis. We review phylogenetically-informed studies that demonstrate freshwater species diversifying from euryhaline ancestors through processes such as landlocking. These studies indicate that some euryhaline taxa are particularly susceptible to changes in halohabitat and subsequent diversification, and some geographic regions have been hotspots for transitions to freshwater. Comparative studies on mechanisms among multiple taxa and at multiple levels of biological integration are needed to clarify evolutionary pathways to, and from, euryhalinity.


Integrating Ecology And Economics For Restoration: Using Ecological Indicators In Valuation Of Ecosystem Services, Eric T. Schultz, Robert Johnston, Kathleen Segerson, Elena Y. Besedin May 2012

Integrating Ecology And Economics For Restoration: Using Ecological Indicators In Valuation Of Ecosystem Services, Eric T. Schultz, Robert Johnston, Kathleen Segerson, Elena Y. Besedin

EEB Articles

Because it can uniquely furnish insights into nonuse values for ecosystem services, survey-based Stated Preference (SP) valuation is widely used to estimate the benefits of ecological restoration. SP surveys ask respondents to select among restoration options yielding different ecological outcomes. This review examines the representation of ecological outcomes in SP studies seeking to quantify values for restoration of aquatic ecosystems. To promote the validity of ecological indicators used in SP valuation, we identified four standards: indicators should be measurable, interpretable, applicable, and comprehensive. We reviewed recent SP studies estimating the value of aquatic ecosystem services to assess whether ecological indicators …


The Effect Of Historical Legacy On Adaptation: Do Closely Related Species Respond To The Environment In The Same Way?, Rachel Prunier, Kent E. Holsinger, Jane E. Carlson Jan 2012

The Effect Of Historical Legacy On Adaptation: Do Closely Related Species Respond To The Environment In The Same Way?, Rachel Prunier, Kent E. Holsinger, Jane E. Carlson

EEB Articles

The many documented examples of parallel and convergent evolution in similar environments are strong evidence for the role of natural selection in the evolution of trait variation. However, species may respond to selection in different ways; idiosyncrasies of their evolutionary history may affect how different species respond to the same selective pressure. To determine whether evolutionary history affects trait-environment associations in a recently diverged lineage, we investigated within-species trait-environment associations in the white proteas, a closely related monophyletic group. We first used MANOVAs to determine the relative importance of shared response to selection, evolutionary history, and unique responses to selection …


Salinity Preference Of Alaskan Threespine Stickleback: Test For Divergence In Halotaxis Between Ancestral And Landlocked Populations, David Fryxell, Eric T. Schultz Jan 2012

Salinity Preference Of Alaskan Threespine Stickleback: Test For Divergence In Halotaxis Between Ancestral And Landlocked Populations, David Fryxell, Eric T. Schultz

EEB Articles

Glacial retreat during the Pleistocene caused landlocking of anadromous Alaskan threespine stickleback, Gasterosteus aculeatus, furnishing a natural ‘experiment’ in osmoregulatory divergence. The objective of this study was to assess the effects of individual acclimation and population divergence on salinity preference. Full-sibling families of marine, anadromous, and freshwater-landlocked populations of stickleback were reared in common environments until 3 weeks post-hatch, then were split and acclimated to low or high salinity. At 6 to 8 weeks of age the six experimental groups were tested for salinity preference in a tank that offers fish a choice of compartments with different salinities arranged …


Estimating Covariation Between Vital Rates: A Simulation Study Of Connected Vs. Separate Generalized Linear Mixed Models (Glmms), Margaret Ek Evans, Kent E. Holsinger Jan 2012

Estimating Covariation Between Vital Rates: A Simulation Study Of Connected Vs. Separate Generalized Linear Mixed Models (Glmms), Margaret Ek Evans, Kent E. Holsinger

EEB Articles

Covariation between vital rates is recognized as an important pattern to be accounted for in demographic modeling. We recently introduced a model for estimating vital rates and their covariation as a function of known and unknown effects, using generalized linear mixed models (GLMM’s) implemented in a hierarchical Bayesian framework (Evans et al. 2010). In particular, this model included a model-wide year effect (YEAR) influencing all vital rates, which we used to estimate covariation between vital rates due to exogenous factors not directly included in the model. This YEAR effect connected the GLMMs of vital rates into one large model; we …


Theory And Design Of Nature Reserves, Kent E. Holsinger Jan 2012

Theory And Design Of Nature Reserves, Kent E. Holsinger

EEB Articles

Notes that accompany a lecture on reserve design when I taught a graduate level course in conservation biology. These notes provide an introductory overview to the theory and design of nature reserves.


Angler Survey Of The Connecticut River, Justin P. Davis Jan 2011

Angler Survey Of The Connecticut River, Justin P. Davis

EEB Articles

The Connecticut River is the largest and most diverse inland fishery resource in the State of Connecticut. Significant improvements in water quality over the past 30 years have led to progressive increases in recreational use, presumably increasing fishing pressure on some species and possibly decreasing overall fishing quality. To address this concern, the Inland Fisheries Division (IFD) of the Connecticut Department of Energy and Environmental Protection (CT DEEP) conducted an angler survey on the entire portion of the Connecticut River within the state during March-October of 2008-09. The survey used a similar design as a smaller-scale survey of the river’s …


Extreme Environments Select For Reproductive Assurance: Evidence From Evening Primroses (Oenothera), Margaret E.K. Evans, David J. Hearn, Kathryn E. Theiss, Karen Cranston, Kent E. Holsinger, Michael J. Donoghue Jan 2011

Extreme Environments Select For Reproductive Assurance: Evidence From Evening Primroses (Oenothera), Margaret E.K. Evans, David J. Hearn, Kathryn E. Theiss, Karen Cranston, Kent E. Holsinger, Michael J. Donoghue

EEB Articles

• Competing evolutionary forces shape plant breeding systems (e.g. inbreeding depression, reproductive assurance). Which of these forces prevails in a given population or species is predicted to depend upon such factors as life history, eco- logical conditions, and geographical context. Here, we examined two such predictions: that self-compatibility should be associated with the annual life history or extreme climatic conditions.

• We analyzed data from a clade of plants remarkable for variation in breeding system, life history and climatic conditions (Oenothera, sections Anogra and Kleinia, Onagraceae). We used a phylogenetic comparative approach and Bayesian or hybrid Bayesian tests to account …


Environmental And Endogenous Factors Influencing Emigration In Juvenile Anadromous Alewives, Benjamin I. Gahagan, Eric T. Schultz, Katie E. Gherard Jan 2010

Environmental And Endogenous Factors Influencing Emigration In Juvenile Anadromous Alewives, Benjamin I. Gahagan, Eric T. Schultz, Katie E. Gherard

EEB Articles

We analyzed juvenile anadromous alewife migration at Bride Lake, a coastal lake in Connecticut, during summer 2006 and found that migration on 24-hour and seasonal timescales was influenced by conditions of the environment and characteristics of the individual. To identify environmental cues of juvenile migration, we continuously video recorded fish at the lake outflow and employed information-theoretic model selection to identify the best predictors of daily migration rate. More than 80% of the approximately 320,000 juveniles that migrated from mid-June to mid-August departed in three pulses lasting one or two days. Pulses of migration were associated with precipitation events, transient …


"Genetics In Geographically Structured Populations: Defining, Estimating And Interpreting Fst.", Kent E. Holsinger, Bruce S. Weir Sep 2009

"Genetics In Geographically Structured Populations: Defining, Estimating And Interpreting Fst.", Kent E. Holsinger, Bruce S. Weir

EEB Articles

Wright's F-statistics, and especially F(ST), provide important insights into the evolutionary processes that influence the structure of genetic variation within and among populations, and they are among the most widely used descriptive statistics in population and evolutionary genetics. Estimates of F(ST) can identify regions of the genome that have been the target of selection, and comparisons of F(ST) from different parts of the genome can provide insights into the demographic history of populations. For these reasons and others, F(ST) has a central role in population and evolutionary genetics and has wide applications in fields that range from disease association mapping …


Temporal Shifts In Demography And Life History Of An Anadromous Alewife Population In Connecticut, Justin P. Davis, Eric T. Schultz May 2009

Temporal Shifts In Demography And Life History Of An Anadromous Alewife Population In Connecticut, Justin P. Davis, Eric T. Schultz

EEB Articles

Populations of anadromous alewives (Alosa pseudoharengus) are declining throughout much of their range, particularly in southern New England where fishery moratoriums have recently been instituted in three states. The alewife run at Bride Brook, a coastal stream in East Lyme, Connecticut, was studied from 2003-06 to assess shifts in demography and life history. Annual censuses of abundance, along with sampling for size, age, and spawning history structure were conducted. These data were compared to similar data in 1966-67 at this site. Recent alewife runs at Bride Brook featured lower abundance and younger, smaller fish that were less likely to be …


Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun Jan 2009

Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring Alosa aestivalis, collectively referred to as river herring, have declined in the Connecticut River. A hypothesis for why river herring have declined is that predation pressures have increased associated with recent increases in abundance of striped bass Morone saxatilis. Information on striped bass abundance, size structure, and consumption rates are required to test this hypothesis. This study was designed to provide estimates of striped bass population size in the Connecticut River during the spring migration season, via an intensive mark-recapture exercise and either an open or robust mark-recapture model. …


Assessment Of River Herring And Striped Bass In The Connecticut River: Abundance, Population Structure, And Predator/Prey Interactions, Justin P. Davis, Eric T. Schultz, Jason Vokoun Jan 2009

Assessment Of River Herring And Striped Bass In The Connecticut River: Abundance, Population Structure, And Predator/Prey Interactions, Justin P. Davis, Eric T. Schultz, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring A. aestivalis, collectively referred to as river herring, have declined in the Connecticut River. An explanatory hypothesis for these declines is that predation pressures have increased as a result of recent increases in abundance of sympatric striped bass Morone saxatilis. We sampled river herring and striped bass from the stretch of the Connecticut River between Wethersfield, CT and Holyoke, MA during the vernal migration seasons of 2005-2008. The objectives of the sampling program were to assess abundance, temporal/spatial distribution, and population structure of both river herring and striped bass, …


Integrating Fluvial Geomorphology And Stream Ecology: Processes Shaping The Distribution Of Freshwater Mussels In Connecticut, Piyumi T. Obeysekara, Eric T. Schultz, Melinda Daniels, Jason Vokoun Jan 2009

Integrating Fluvial Geomorphology And Stream Ecology: Processes Shaping The Distribution Of Freshwater Mussels In Connecticut, Piyumi T. Obeysekara, Eric T. Schultz, Melinda Daniels, Jason Vokoun

EEB Articles

No abstract provided.


A Sex Difference In Seasonal Timing Of Birth In A Livebearing Fish, Eric T. Schultz Jan 2008

A Sex Difference In Seasonal Timing Of Birth In A Livebearing Fish, Eric T. Schultz

EEB Articles

Sex differences in seasonal timing include differences in hatch- or birth-date distribution and differences in the timing of migration or maturation such as protandrous arrival timing (PAT), which is early male arrival at breeding sites. I describe a novel form of protandrous arrival timing, as a sex difference in birth-date distribution in a live-bearing fish (Dwarf Perch, Micrometrus minimus). In this species, birth coincides with arrival at breeding sites because newborn males are sexually active. A series of samples of pregnant females and young of year was collected in Tomales Bay, CA. I analyzed the daily age record in otoliths …