Life Sciences Commons^™

Anadromous Rainbow Smelt And Tomcod In Connecticut: Assessment Of Populations, Conservation Status, And Need For Restoration Plan, Heather A. Fried, Eric T. Schultz

EEB Articles

(beginning of rainbow smelt executive summary)

Evidence indicates that anadromous rainbow smelt (Osmerus mordax) populations in Connecticut and elsewhere in the northeast United States have severely declined. Several sampling programs have documented declines in Connecticut’s smelt populations over the last three decades (Marcy 1976a, Marcy 1976b, Millstone Environmental Laboratory 2005). Similar declines have also been documented in the Hudson River (ASA Analysis & Communication 2005) and in Massachusetts (personal communication, Brad Chase, MA Division of Marine Fisheries 2004). Recreational and commercial fisheries in the region for this species have virtually ceased (Blake and Smith 1984). The Connecticut Fish Advisory Committee …

Assessment Of Anadromous Alewife And Blueback Herring Populations In Connecticut Coastal Streams And Connecticut River Tributaries, Justin P. Davis, Eric T. Schultz

EEB Articles

Alewife (Alosa pseudoharengus) and blueback herring (A. aestivalis) occur in anadromous populations that have a largely overlapping distribution from Florida to Newfoundland (Loesch 1987). Anadromous populations of these species are commonly collectively referred to as “river herring”. Adults inhabit coastal shelf waters until sexual maturity is reached at age 3-5 (Neves 1981). Sexually mature individuals make spawning migrations, commonly referred to as “runs”, into freshwater systems during spring months (Loesch 1987). Spawners can survive and return to spawn in subsequent years (Mullen et al. 1986). Juveniles reside in freshwater for 3-7 months, at which time they undertake a gradual migration …

When Hybrids Go Wrong. How Hybridization Can Create Invasive Species., Carol Auer, Collin Ahrens

Plant Science Presentations and Proceedings

Gene flow is the movement of genes from one plant population to another. Gene flow is a natural process and a part of plant evolution. There are two ways for gene flow to occur in plants. The first is through sexual reproduction – pollen lands on a flower and a viable seed develops. The second method is through dispersal of seeds and/or vegetative plant parts (e.g. stolons, rhizomes). Gene flow can produce hybrid offspring with an increased or decreased ability to survive in the landscape. If hybrid offspring have some advantage in the environment, they could become invasive. This poster …

Decreased Reproductive Investment Of Female Threespine Stickleback Gasterosteus Aculeatus Infected With The Cestode Schistocephalus Solidus: Parasite Adaptation, Host Adaptation, Or Side Effect?, Eric T. Schultz, Michelle Topper, David C. Heins

EEB Articles

Parasitic infections may cause alterations in host life history, including changes in reproductive investment (absolute amount of energy allocated to reproduction) and reproductive effort (proportion of available energy allocated to reproduction). Such changes in host life history may reflect: 1) a parasite tactic: the parasite adaptively manipulates energy flow within the host so that the host is induced to make a reduction in reproductive effort and reproductive investment, making more energy available to the parasite; 2) no tactic: there is no change in host reproductive effort and reproductive investment simply decreases as a side effect of the parasite depleting host …

The Dynamics Of Bay Anchovy In The Hudson River Estuary: Process-Oriented Studies And Long-Term Changes, Eric T. Schultz, Kamazima M. M. Lwiza, John R. Young, Kyle J. Hartman, R. C. Tipton

EEB Articles

We review three areas of recent research on Hudson River bay anchovy. One focus has been the along-estuary movement of early life stages. A cohort analysis of samples collected in a spatiotemporally extensive monitoring program has confirmed that early-stage anchovy migrate up-estuary, at an estimated rate of 0.6 km/d. Complementary fine-scale field sampling was designed to clarify behaviors that effect the migration. This work found that early-stage anchovy can show preferences for depth and can conduct periodic vertical migration. To determine whether these behaviors were sufficient to produce up-estuary migration, larval flux and velocity were estimated. These estimates were consistent …

The Essentials On Estuarine Fish Habitat, Its Evaluation And Protection By Federal Fisheries Law, Eric T. Schultz, Michael Ludwig

EEB Articles

No abstract provided.

Distribution, Habitat Use, Growth, And Condition Of A Native And An Introduced Catfish Species In The Hudson River Estuary, Stephen M. Jordan, Robert M. Neumann, Eric T. Schultz

EEB Articles

White catfish (Ameiurus catus) is native to the Hudson River and is now coexisting with the recently established channel catfish (Ictalurus punctatus). These species were sampled from four freshwater reaches and four habitat types of the Hudson River estuary to assess whether the two species overlapped in their habitat use, and whether any impact on the native species was evident. Catfishes were sampled in 1998 and 1999 using baited hoop nets (N = 708 net nights). Catch-per-unit-effort (CPUE, number of fish per net night; total catch = 368) of white catfish was significantly different among reaches …

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 …

Do Naked Goby (Gobiosoma Bosci) Larvae Exhibit Periodic Vertical Movements In Order To Facilitate Upriver Migration In The Hudson River Estuary?, Megan C. Fencil, Eric T. Schultz

EEB Articles

Estuaries provide high quality nursery habitat for larval fishes due to high productivity, predator protection, and warm temperatures. Previous studies suggest that larval naked gobies (Gobiosoma bosci) are capable of upriver migration and estuarine retention despite net seaward flow. Gobiosoma bosci larvae were collected at a fixed site in the Hudson River estuary in late July of 1998 from 4 discrete depths to provide a time-series of depth-stratified abundance during both a spring and a neap tide. Larvae were concentrated at depth, indicating that depth preference behavior is present and will likely contribute to up-river transport. Harmonic regression …

Recruitment Of Coral Reef Fishes To Bermuda: Local Retention Or Long-Distance Transport?, Eric T. Schultz, Robert K. Cowen

EEB Articles

The benthic marine fauna of isolated oceanic islands may be self-seeding, or alternatively may be continually supplied with recruits advected from elsewhere by ocean currents. Estimates of the time required for transport of larvae from elsewhere was combined with information on the larval durations of fishes inhabiting the reefs of Bermuda, to test the hypothesis that other populations are sources for recruits to Bermuda. Specifically, we tested the prediction that transport occurs frequently enough to sustain local populations of reef fishes. Transport of larvae was modelled as a 2-step process in several numerical simulations. The first step of transport was …

Historic Trends In The Distribution And Populations Of Estuarine Marsh Birds Of The Connecticut River, Robert J. Craig

Storrs Agricultural Experiment Station

No abstract provided.

Social Transmission Of Behavioural Traditions In A Coral Reef Fish, Gene Helfman, Eric T. Schultz

EEB Articles

Traditional behaviours involve the non-genetic transmission of social information across age classes or generations. French grunts (Haemulon flavolineatum) exhibit social traditions of daytime schooling sites and twilight migration routes. Individuals transplanted to new schooling sites and allowed to follow residents at the new sites used the new migration routes and returned to the new sites in the absence of resident fish. Control fish with no opportunity to learn showed no such directionality or return. This is the first demonstration of apparent pre-cultural behaviour in free-living fish. Our observations suggest additional classes of behaviour and taxonomic groups in which …