Current Grants

Project 1

Title: Sustaining fishery yields over evolutionary time scales: Are harvest-induced genetic changes permanent?

Start date: 06/01/04
End date: 05/31/07
Funding agency: Pew Institute for Ocean Science
Funding: USD 329,734

Principal Investigator and Project Manager:
David O. Conover, Professor
Dean and Director
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Summary
Fishery science theory assumes implicitly that the effects of harvest on wild populations are entirely ecological in nature and therefore reversible over relatively short time scales. Harvest mortality, however, is highly selective with respect to life history traits such as body size. If life history traits are heritable and if genotypes that code for life history are non-randomly removed by fishing, then evolutionary genetic changes are highly likely. Recent research on the Atlantic silverside, Menidia menidia, has provided the first experimental evidence that the intrinsic growth rates of fish and the productivity of populations can evolve rapidly in response to size-selective harvest regimes. Here we propose to extend this experiment to examine the evolutionary response of harvested populations to cessation of size-selective fishing. In essence, the question is: "Will the genetic changes in population productivity caused by size-selective harvest be reversed when selective fishing ceases?"
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Project 2

Title: Local adaptation across latitudes: spatial scales, gene flow, and correlates of countergradient growth variation

Start date: 10-15-2007
End date:
Funding agency: National Science Foundation

Funding: USD

Principal Investigator and Project Manager:
David O. Conover, Professor
Dean and Director
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Co-Investigator:
Paul H Barber
Boston University
Biology/Marine Program
881 Commonwealth Avenue
Boston, MA. 021151303

Summary
Knowledge of geographic patterns in adaptive genetic variation is crucial to species conservation yet in marine systems our understanding of this phenomenon is virtually nil. Until recently, the belief has been that because most marine species have highly dispersive or mobile life stages, local adaptation could occur only on broad geographic scales. This view is supported by comparatively low levels of genetic variation among populations as indexed by surveys of DNA markers neutral to selection. Phenotypic variation is expected to be largely of environmental origin, especially for physiological traits that are highly sensitive to environmental conditions. Stimulated by studies of the Atlantic silverside (Menidia menidia) and other species, these long-held beliefs are rapidly changing. The silverside shows dramatic evidence of highly structured local adaptation in a suite of coevolving physiological and morphological traits tightly associated with climate change across latitudes along the east coast of North America. Yet preliminary data from molecular genetic surveys suggest extensive gene flow along the entire latitudinal range. This proposal addresses two central problems. The first concerns the micro-geography of local adaptation. How finely scaled is it? How is it influenced by gene flow? Is it closely tied to physical features of the coastline? Do multiple traits co-vary similarly along the same gradient? The second problem focuses on the evolution of growth rate, a trait that strongly displays countergradient latitudinal variation not only in the silverside but also in numerous other taxa. Recent experiments show that growth rate can evolve very rapidly in response to size-selective mortality, including genetic changes caused by fishing. This project will examine the correlates of growth rate evolution. We will study how trade-offs with growth rate influence development, behavior, morphology, and the ability of animals to defend against disease. Our research integrates biogeography, physiology, quantitative and molecular genetics, behavior, immunology, and developmental biology. It draws upon natural and experimentally evolved populations, thereby allowing rigorous testing of hypotheses that would be impossible in most other marine species.

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Project 3

Title: Recruitment of bluefish in the Middle and South Atlantic Bights: effects of an ovarian nematode parasite and spatio-temporal patterns of juvenile recruitment

Start date: 05/01/04
End date: 10/30/07
Funding agency: Institute of Marine and Coastal Sciences Rutgers University
Funding: USD 219,210

Principal Investigator and Project Manager:
David O. Conover, Professor
Dean and Director
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Co-PI
Alistair Dove, Assistant Professor
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Sean Moser, Postdoctoral Research Assoc.
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Summary
We propose to investigate two different but inter-related topics that will contribute greatly to our understanding of the factors that affect the recruitment of bluefish along the U.S. Atlantic coast. First, we will expand upon our recent discovery of very high levels of infection by a parasitic nematode worm in the ovaries of spawning bluefish sampled in New York and North Carolina in 2002 and 2003. This worm was identified as a blood-feeding dracunculoid nematode in the genus Philometra. Significant pathologies were associated with infection, including interstitial haemorrhage in ovarian connective tissue, fibrosis, granulomatous and lymphocytic inflammation and follicular atresia. We hypothesize that this ovarian parasite may be a major factor influencing the reproductive success and inter-annual recruitment variability of bluefish. We propose to characterize the distribution and abundance of this parasite in bluefish, focusing on the onset of infection in age-0 juvenile bluefish (when Philometra first appears) and on females during the spawning season when intense infections are concentrated in ripe ovaries. We will quantify the damage to ovarian function using histopathology and by scaling of the prevalence, extent and severity of the parasite and induced-lesions. In the process, we expect to gain insight into the life-cycle of the parasite and how pathogenesis relates to reproductive potential of bluefish at both individual and population levels. We will also determine whether this species of Philometra is the same as that infecting striped bass, potentially linking the dynamics of these two fish species through a shared parasite. The second objective is to participate in a "coordinated, multi-investigator, multi-year, coastwide, synoptic study using specific gears and methods, and a broad-scale designed survey" as stated in the Report on the Bluefish Research Program Workshop (19-20 May 2003) and reiterated in the Bluefish Research Program 2004 Request for Proposals. We hypothesize that the abundance of YOY cohorts of bluefish differ across their latitudinal range and among habitats with regions. The design, approach, and research products of our proposed research in New York will share core elements with coordinated efforts in the South and Mid-Atlantic Bights, including New Jersey (K. Able, P.I.), DelMarVa (D. Secor and E. Houde, P.I.s), and North Carolina (T. Lankford and J. Buckel, P.I.s). Our contribution to this coastwide effort will be coordinated with, and leveraged by, a bottom trawl survey program that NYDEC plans to conduct in continental shelf waters. 2
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Project 4

Title: Survey of Atlantic Sturgeon Population; Ocean Trawl Survey for Subadult Atlantic Sturgeon

Funding agency: New York Department of Environmental Conservation.
Pending Funding

Principal Investigator and Project Manager:
David O. Conover, Professor
Dean and Director
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Co-PI
Sean Moser, Postdoctoral Research Assoc.
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Summary
Due to continued low levels of recruitment, ASMFC is concerned that sturgeon recovery has been hindered by losses in the near shore ocean. We know little about abundance and habitat use of Atlantic sturgeon in the ocean off the 100 miles of coastline on the south side of Long Island. However, fishermen have mentioned capturing small Atlantic sturgeon south of Long Island. One fisherman brought pictures of juvenile sturgeon approximately 1.5 - 2 feet long that were caught off the beach near Moriches Inlet. Another fisherman said this summer that he caught so many sturgeon near shore between Fire Island and Shinnecock Inlet that he had to stop fishing. An Anadromous Sturgeon Symposium was held this summer at the American Fisheries Society Annual Meeting. Several presenters described aggregations of sturgeon in near shore ocean habitat. We propose a two year survey of New York StateÕs ocean habitat to determine where and when sturgeon occur off the south shore of Long Island. This information is needed to determine potential impacts from bycatch in non-directed fisheries and proposed Energy projects such as pipelines, cables, and wind generation. In addition, information on other species of special concern will also be collected through this survey including: horseshoe crabs, winter flounder, spiny dogfish, and American lobsters. This information will be useful for assessment purposes.
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Project 5

Title: Annuals beach-seine surveys of the abundance of young-of-the-year fishes in the Hudson River estuary.

Start date: 05/01/2004
End date: 04/31/2008
Funding agency: New York Department of Environmental Conservation.
Funding: USD

Principal Investigator and Project Manager:
David O. Conover, Professor
Dean and Director
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Co-PI
Sean Moser, Postdoctoral Research Assoc.
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Summary
This project involves the continuation of a >20 year-old survey of the abundance of YOY fishes in the Lower Hudson River, focusing primarily on striped bass. Beach seine sampling is conducted at 25 sites within the Lower Hudson River every two weeks from July through November. This long-term data base provides an excellent opportunity to evaluate factors associated with recruitment variability of a diverse community of estuarine fishes. A variety of specific research projects will be developed after initial statistical analyses of the overall database are completed.

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Project 6

Title: Factors influencing the abundance and distribution of Atlantic silversides, Menidia menidia, in the Hudson River

Start date: 06/01/05
End date: 05/31/07
Funding agency: Hudson River Foundation
Funding: USD 53,309

Principal Investigator and Project Manager:
David O. Conover, Professor
Dean and Director
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Principal Investigator and Project Manager:
Lora M. Clarke
Ph.D. Candidate
Marine Sciences Research Center
State University of New York
Stony Brook, NY 11794-5000

Summary
The Atlantic silverside, Menidia menidia, is one of the most abundant fish species in the Hudson River. Over the last 25 years, the percentage of silversides relative to other fish species captured in beach seine surveys has continued to increase and silversides now dominate the catch. Despite the ecological importance of the Atlantic silverside to local food webs and its high abundance, no one has studied the population dynamics of this species in the Hudson River or nearby estuaries in detail. Here we propose the first study to investigate population dynamics of the Atlantic silverside in the Hudson River. Our goal is to examine trends in Atlantic silverside abundance and to investigate factors influencing the within-river distribution and interannual variation in overall abundance in the Hudson River and to determine if these trends are related to those of nearby estuaries.

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