Alewife Population Assessment and Aquaculture

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Project Type: 
Research
Project Number: 
R/SSS-1
Inception Date: 
2012
Completion Date: 
2014

Participants:

Matthew DiMaggio UNH - Department of Biological Sciences Postdoctoral Student/Researcher
David Berlinsky UNH - Department of Biological Sciences Principal Investigator
Michael Bailey U.S. Fish and Wildlife Service Associate Investigator
Kevin Sullivan N.H. Fish and Game Department Associate Investigator
Ken La Valley UNH - Cooperative Extension Associate Investigator
Erik Chapman N.H. Sea Grant Associate Investigator
John Whalen Harmon Brook Farm Industry Partner
Abstract: 

Together with smelt, river herring (alewives and blueback herring) comprise the most dominant anadromous species in the Great Bay estuary system and support limited fisheries. Due to coast-wide declines in river herring populations, the Atlantic states Marine Fisheries Commission’s (ASMFC) Amendment 2 to the Interstate Fisheries Management Plan for shad and river herring calls for states to close recreational and commercial river herring fisheries, with an exception for those that can demonstrate sustainable fisheries. Currently, river herring populations in New Hampshire are monitored by spawning stock returns in fish ladders on four of the seven major rivers in the estuary. Many questions regarding the efficacy of this evaluation method must be addressed, however, to determine its value in estimating annual recruitment to the fishery. In this proposal, we outline a project for collaborative research with 2 goals aimed at alewife conservation. We will: 1) examine the accuracy of river herring population assessment methods currently used in the Great Bay Estuary and 2) develop methods for alewife aquaculture for both stock enhancement and as a marine baitfish.

Objectives: 
1.     Examine the accuracy of river herring population assessment methods currently used in the Great Bay Estuary and develop methods for their improvement
 
2.     Establish methodology for alewife aquaculture for both stock enhancement and as a marine baitfish
 
3.     Develop an outreach and extension program to disseminate results to appropriate audiences
Methodology: 
Populations will be assessed by determining juvenile outmigration above the head of tide dams (adjacent to fish ladders) and on dams below out-planted ponds. Estimates of fish ladder efficiency will be determined by tagging 500 alewives below the fish ladders in 4 rivers and documenting daily up-river migration. A fish ladder independent productivity index will be generated by developing and optimizing egg collectors appropriate for river herring. For alewife aquaculture, commercial-scale production will be achieved by investigating the use of Fuller’s earth (5 and 10 g/L) and tannic acid (150, 300, 600, 900 mg/L) for removing egg adhesiveness and hydrogen peroxide (500, 1000, 2000, 3000 ppm), PVP-Iodine (25, 50, 75, 100 ppm), and chlorine dioxide (CD; 2, 4, 8, 16 ppm) as egg disinfectants. Larvae will be cultured with and without the addition of microalgae at 18, 21 and 24 °C with different light intensities (10, 50 and 100 LUX). Appropriate end users will be contacted through peer-reviewed and trade journals, husbandry workshops and reports to management agencies.
Rationale: 
River herring populations have exhibited drastic declines throughout much of their range and were listed as U.S. National Marine Fisheries Service “species of concern” in 2006. Due to these declines, the Atlantic States Marine Fisheries Commission’s (ASMFC) Amendment 2 to the Interstate Fisheries Management Plan for shad and river herring, calls for states to close recreational and commercial river herring fisheries, with an exception for those that can demonstrate sustainable fisheries. In response to these declines, several states including Rhode Island, Massachusetts, Virginia and North Carolina have instituted moratoria on river herring harvest and possession. Personnel at the U.S. Fish and Wildlife Service and state fish and game agencies have expressed considerable interest in restoration of alewife populations through hatchery production and limited stocking has already been initiated for this purpose. In addition to stock enhancement, the increasing demand for baitfish for the marine recreational fishing industry offers enormous economic opportunity for baitfish culture. Baitfish culture offers significant opportunites to economically depressed commercial fishing communities and aquaculture entrepreneurs.
Accomplishments: 

2014

N.H. Sea Grant research indicates alewives may not be able to easily ascend fish ladders to spawn in N.H. rivers
Alewives are experiencing population declines throughout their range in New England waters. NHSG-funded researchers conducted tagging studies on four N.H. rivers to determine if fish ladders act as a barrier to upstream migration, possibly impacting their ability to spawn. Data results compiled in 2014 indicated that alewives do not always ascend fish ladders continuously during the spawning season, but instead may make several attempts or may cease trying. This information helps resource managers to better understand the challenges posed by fish ladders to migrating fish populations, thus improving their ability to manage the fishery.

2013

Two videos inform and engage the public about N.H. Sea Grant research
N.H. Sea Grant produced two videos in 2013 about research projects focused on microplastics on N.H. beaches and alewife populations in coastal rivers. Both research projects were funded by NHSG. The videos were shared on social media and one was uploaded to the research page of the NHSG website, allowing the description of the research to evolve into a “living document” and gain a longer shelf-life in the news. Videos serve as a companion piece to written news stories about the research, engaging audiences in a more effective manner and encouraging volunteer participation in the research when possible, as was the case with the microplastics project.

2012

Protocols Developed for Alewife Culture Lead to Direct Economic Benefits for Business
RELEVANCE: Smelt, alewives and blueback herring comprise the most dominant anadromous species in the Great Bay Estuary and support limited fisheries. However, recent coastwide declines in their populations are causing concern. Producing alewives via aquaculture could aid in both stock enhancement and marine baitfish supply, taking some pressure off the wild populations to ensure their sustainability.
RESPONSE: NHSG-funded researchers developed protocols in 2012 for alewife broodstock spawning, larviculture and juvenile rearing, including the establishment of salinity tolerances for larval and juvenile alewives. Researchers demonstrated the ability to successfully mass-produce thousands of young alewives in an aquaculture setting.
RESULTS: Harmon Brook Farm in Caanan, Maine, is using these protocols to culture alewives for marine baitfish purposes. This company has benefited financially from the production and sale of alewives based on these protocols and they plan to increase production in the coming years.
RECAP: NHSG-funded researchers developed alewife aquaculture protocols that are being used in a marine baitfish supply business, providing direct economic benefits.

Researchers Developed Protocols Resulting in First Mass-production of Juvenile Alewives in Captivity
Smelt, alewives and blueback herring comprise the most dominant anadromous species in the Great Bay Estuary and support limited fisheries. Recent coastwide declines in their populations are causing resource managers to seek ways of ensuring their populations are sustainable. Stock enhancement may be a viable option to achieve that goal. To that end, NHSG-funded researchers developed protocols in 2012 for alewife broodstock spawning, larviculture and juvenile rearing, resulting in the production of thousands of juveniles in a lab setting. This research is the first documented example of mass-producing juvenile alewives in captivity. These aquaculture protocols will enable resource managers and individuals interested in marine baitfish to supply alewives for economic and ecological benefit.

Studies Indicate Larval Alewives are Tolerant of Full-strength Seawater while Raised in Captivity
Alewife populations have experienced recent coastwide declines, causing resource managers to seek ways to ensure their sustainability. Stock enhancement from lab-raised broodstock may prove beneficial to meet that goal. During the development of aquaculture protocols for raising alewives, researchers conducted experiments in 2012 to establish salinity tolerances for larval and juvenile alewives. Their results indicated that larval alewives (about 45 days post-hatch) are tolerant of full-strength seawater. These results will provide more accurate information for aquaculturists to successfully raise alewives for stock enhancement and marine baitfish supply.

Tagging Studies Help Improve Alewife Population Estimates in N.H. Rivers
Alewife populations in N.H. are currently monitored by spawning stock returns in fish ladders on four rivers leading into Great Bay. In light of recent coastwide declines in alewife populations, it is essential to accurately monitor and estimate their populations and recruitment to the fishery to ensure sustainability. With funding provided by NHSG, researchers conducted preliminary stock assessment monitoring in 2012 on alewives in those four rivers to determine if current monitoring efforts are accurate. Fish were captured below the river dams, tagged and returned below the dams. Recaptures ranged from 0% - 71% covering 11 tagging events total. The results of these and other tagging studies will enable researchers to improve alewife population estimates, thus providing more accurate information for resource managers seeking to ensure sustainable fish stocks.

Publications

Available from the National Sea Grant Library (use NHU number to search) or NH Sea Grant

Journal Article

  • DiMaggio, M.A., H.J. Pine, L.W. Kenter and D. Berlinsky. Spawning, larviculture, and salinity tolerance of alewives and blueback herring in captivity. North American Journal of Aquaculture 77(3):302-311, July 2015.
  • Berlinsky, D.L., T.S. Breton, J. Walsh and A.I. Kovach. Peritoneal pigmentation in purebred and hybrid river herring. Transactions of the American Fisheries Society 144(4):717-723, July 2015.
  • Berlinsky, D., M. Watson, M. DiMaggio and T. Breton (2016). The use of tricaine methanesulfonate, clove oil, metomidate and 2-phenoxyethanol for anesthesia induction in alewives. North American Journal of Aquaculture 78(1):84-91, January 2016.

Thesis/Dissertation

  • Watson, M. (2015). The use of tricaine methanesulfonate, clove oil, metomidate, and 2-phenoxyethanol for anesthesia induction in alewives (Alosa pseudoharengus). Master's thesis, University of New Hampshire.

CD/Video

  • N.H. Sea Grant alewife research (2013) (video). See N.H. Sea Grant's YouTube channel.