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1998

SCOTIA-FUNDY ELVERS

INTEGRATED FISHERIES MANAGEMENT PLAN

MARITIMES REGION

Glass Eel

(Anguilla rostrata)


TABLE OF CONTENTS

LIST OF APPENDICES

APPENDIX 1
Scotia-Fundy Elver Advisory Committee Terms of Reference

APPENDIX 2
Scotia-Fundy Elver Advisory Committee Membership List

APPENDIX 3
Scientific Research Documents 95/2 and 95/04

APPENDIX 4
Dockside Monitoring Guidelines for the Elver Fishery


SCOTIA-FUNDY ELVERS

INTEGRATED FISHERIES MANAGEMENT PLAN

I. OVERVIEW OF THE FISHERY

Elvers are defined under the Maritime Provinces Fishery Regulations as eels less than 10 cm in length. Biologically, elvers are the post larval, early juvenile stage of the American eel (Anguilla rostrata) which migrate as larvae from the adult eel´s spawning grounds in the Sargasso Sea to the coastal waters of Eastern North America. Elvers typically arrive in waters of the Maritime Provinces from late March to August. Elver distribution is random and there is no "homing". In other words, elvers do not return to the river or estuary where their parents originated.

In the early to mid-1980´s, a few experimental licences were issued to individuals who expressed an interest in trying to catch elvers. No elver landings were reported under these licences so they were not renewed in subsequent years. In 1989, two experimental licences were issued to fish elvers which, for the first time, resulted in landings of 26 kg for the year. The fishery developed slowly and total annual landings remained well below a tonne. By 1994, there was a total four experimental licences and, for the first time, landings surpassed one tonne and reached 1,574 kg. The potential for economic viability appeared attainable. When landings reached 3,338 kg in 1995, there was a dramatic increase in the demand for licences which prompted Fisheries and Oceans Canada (DFO) to move to a public process for the issuance of new licences. In 1996, licences were temporarily capped in the Scotia-Fundy sector at nine - six permitted direct sale and three permitted harvest for domestic aquaculture purposes. In 1997, four of the experimental licences were made permanent.

In 1998, approval was given for two additional experimental elver licences. One of the experimental licences was issued to an association of commercial eel fishers in Shelburne County, who agreed to cease adult eel fishing. The other experimental licence is approved for issuance in 1999 to a commercial eel fisher in Richmond County who has agreed to cease adult eel fishing in return for an experimental licence to fish elvers for domestic aquaculture purposes.

1.1 Participants

Nine (9) licences were eligible for renewal in 1997. Six (6) of these licences authorized commercial sale of elvers while three (3) permitted harvesting for domestic aquaculture purposes and prohibited sale. One of the experimental licences which permitted harvest for aquaculture purposes was not renewed by the holder in 1997. Licences are issued to an individual (with the exception of one issued to an association of commercial adult eel fishers) but specify that others can fish under the licencee´s direction. It is normal for licence holders to employ up to two (2) persons for each river that they are authorized to fish. Information provided by licence holders shows that most of the individuals hired were also employed in other seasonal jobs, including fishing, or were students.

1.2 Location of Fishery

Elver fishing takes place at or near the head of tide at the mouth of rivers. Following consultations with commercial adult eel fishermen, elver fishing is not permitted on rivers where there are established adult eel fisheries. The current elver fishery occurs in Southwest New Brunswick, the Upper Bay of Fundy, Southwest Nova Scotia, along the Eastern Shore of Nova Scotia, and in portions of Cape Breton Island.

1.3 Timeframe of the Fishery

Elvers typically arrive in Scotia-Fundy waters in late March and early April with the peak run usually in May. They appear first in Southern areas of Nova Scotia and the Bay of Fundy and later along the Eastern Shore and in Cape Breton.

1.4 Landings/Value

Elver landings from Scotia-Fundy waters have increased from 26 kilograms in 1989 to 4,122 kilograms in 1997. (See TABLE below). The price paid for elvers has fluctuated from a low of about $60 per kilogram in 1989, when the experimental fishery first began, to a high of $800 per kilogram for a time in 1995. (Fluctuations in prices depend mainly on worldwide landings of elvers and the demand for cultured eels). The average price paid for elvers in 1997 was approximately $500 per kilogram, bringing the landed value to an estimated $2 million. The majority of elvers harvested in Scotia-Fundy waters are exported either via the US or directly to Asia for aquaculture grow-out. The remainder are used in domestic aquaculture facilities currently located in Springhill, Nova Scotia, and Port Elgin and St. George, New Brunswick.


TABLE I

____________________________________________________

Annual catches (kg) of American eel elvers in Scotia-Fundy waters, by province, 1989 - 1997

____________________________________________________

Year

New Brunswick

Nova Scotia

Total

1989

0

26

26

1990

132

42

174

1991

65

0

65

1992

227

0

690

1993

534

156

690

1994

650

924

1574

1995

549

2689

3238

1996

451

2414

2865

1997

852

3270

4122

1.5 Consultative Process

In December, 1996, following a meeting with elver licence holders, it was agreed to establish a formal advisory committee. A formal Advisory Committee was struck on February 20, 1998. Terms of Reference and the membership list for the Committee can be found in Appendix 1.

1.6 Management Style

To date, the elver fishery has been managed on the basis of an enterprise allocation (EA) system. Each licence holder is authorized to fish specific rivers within a defined geographic area. Each licence specifies a maximum quantity (TAC) of elvers that can be harvested and also caps the amount that can be taken from any individual river.


II. STOCK STATUS

(See Appendix 2 Research Document 95/2 - Justification for, and status of, American Eel Elver Fisheries in the Scotia-Fundy Region and Research Document 95/04 - Review of the American Eel Elver Fisheries in Scotia-Fundy, Maritimes Region.)

2.1 Prospects for 1997/98

The unique life history of American eels (panmictic spawning, environmental influences on eel larval/elver survival and distribution) prohibits forecasting of the quantity of elvers arriving at any Maritime location.

2.2 Environment and Habitat

The nature of the biological and physical conditions that influence eel larval and elver survival and distribution in marine waters are largely unknown. It has been hypothesized that a recent weakening of the Gulf Stream interfered with larval transport and caused the observed declines in elver abundance in the Gulf of St. Lawrence. However, aside from observing generally that factors such as water temperature can influence growth and mortality rates of larval fishes and that water currents such as the Gulf Stream greatly affect the timing and rate of coastwide larval eel/elver distribution, our knowledge is limited. In freshwater, changes (often man-made) that prevent access to or degrade rearing habitat and excessive fishing pressure may reduce the eel stock abundance within a river and ultimately, if spread over a sufficient geographic area, reduce the spawning stock size, but detailed measurements of such affects are unavailable. The adequacy of fish passage for eels at man-made obstructions in the Maritime Provinces has not been evaluated but is viewed as a potentially serious problem.

2.3 Species Interactions

The interactions of American eels with other species in marine and freshwater environments are poorly understood. Eels at all life stages are prey for other species but their importance to any predatory species is unknown. In freshwater, eels primarily feed on invertebrates such as insect larvae, crustacea, etc., but small forage fishes are taken by larger eels. Minor predation by larger eels on young salmonids has been observed, although eels and salmonids are somewhat separated by differences in habitat preference - eels prefer waters that are warmer and of slower velocity than do salmonids. Concerns over such interactions are more economic than biological since they are a natural part of Maritime freshwater ecosystems.

2.4 Research

Minimal research on American eels occurs in Scotia-Fundy due to fiscal restraint and other priorities. Present studies include an annual assessment of the run size and biological characteristics of elvers entering the East River, Sheet Harbour and an analysis of the age and growth of larger American eels collected from several sites in the Saint John River during the early 1990s. A Joint Venture Project (DFO and a group of elver fishers) was carried out in 1996, 1997 and 1998 to study the efficiency of dipnet fishing for elvers in a small river.


III. LONG-TERM OBJECTIVES FOR FISHERY

The elver fishery is unique in that harvesting is carried out from shore or in-river with little or no use of vessels. Nevertheless, it is a fishery which is an ideal candidate for an enterprise allocation (EA) program. It is a single specie fishery with a limited number of participants who are licensed for specific rivers. The long-term objectives for this fishery, therefore, are biological sustainability and economic viability through the formalization and maintenance of an EA program.

IV. MANAGEMENT OBJECTIVES

The management objectives for the elver fishery are:

• to ensure conservation of the eel resource;

• to provide a sustainable fishery resulting in increased economic benefits to Canadians; and

• in cooperation with, or through formal partnership agreements with licence holders, to increase the scientific data base on elvers in Scotia-Fundy waters.

4.1 International Considerations

American eels are from a single spawning stock, i.e., eels from all areas of their geographic range spawn in the Sargasso Sea. Juveniles are then randomly distributed through the entire range under the influence of ocean currents, tides, wind, river discharge, etc. The life cycle of the eel requires that the overall stock is managed in both Canada and the United States so that over-exploitation does not occur at any life stage.

4.2 Domestic Considerations

4.2.1 Aboriginal

Aboriginal people have historically fished adult eels throughout Nova Scotia and New Brunswick. First Nations in Cape Breton initially expressed some concerns about the experimental elver fishery and the potential affect on their adult eel fishery. Elvers captured in a particular river in Nova Scotia and New Brunswick have committed to that particular river and, therefore, are not destined for other areas. The removal of elvers from a river in Eastern Nova Scotia, for example, will not directly impact on the adult eel population in Cape Breton.

Through informal discussion, there has been more acceptance among Aboriginal people, particularly in Cape Breton, that a well managed elver fishery can provide an economic opportunity without jeopardizing the adult eel fishery. As a result, and in accordance with the provisions of the Aboriginal Fisheries Strategy, an experimental licence was issued to the Waycobagh First Nation in 1996, 1997, and 1998.

4.2.2 Commercial

The elver fishery in Scotia-Fundy operated on an experimental basis from 1989 to 1997. In 1997, four (4) experimental licence holders, who demonstrated significant catches for the previous two (2) years, were issued regular licences. This approach is consistent with the Minister´s policy for developmental fisheries which provides that experimental licence holders may be given priority for regular licences.

Considerable time and financial commitments have been made by the experimental licence holders in the development of this fishery. That commitment is recognized. Improvements, particularly in holding facilities, is essential to provide top quality elvers thereby maximizing their value and extending employment time for workers. It is unrealistic to expect licence holders to indefinitely continue making large financial commitments for facilities and marketing if licences remain experimental.

4.2.3 Aquaculture

Three (3) of the experimental elver licences issued in Scotia-Fundy are for domestic aquaculture purposes only. They were first issued in 1995/96 in an attempt to reduce the cost of raw material for individuals proposing domestic grow-out rather than export for grow-out. Priority over other applicants was given to aquaculture proponents because of anticipated benefits to be derived from a value added product and because of both the federal and provincial government commitment to aquaculture development. Consistent with this commitment, elver harvests in the area from Halifax/Dartmouth to the Guysborough County line have been set aside exclusively for the stocking of aquaculture facilities. Currently, one licence holder is authorized to fish in this area. If it is determined that sufficient elvers are available in this area to support additional aquaculture operations, the issuance of any new licences would be contingent on the submission of a comprehensive business plan and a review by the Elver Advisory Committee.

One of the three (3) individuals who held an experimental licence to fish elvers for domestic aquaculture purposes failed to renew the licence in 1997. As a result, and in accordance with current licensing policy, that licence is not renewable in 1998.

4.2.4 Recreational

No consideration is being given to a recreational elver fishery.

4.2.5 Experimental

Consistent with scientific advice, additional experimental licences will be restricted to areas currently unfished for elvers. This criteria, in addition to the policy that prohibits elver fishing on rivers with established adult eel fisheries, severely limits the number of additional elver licences that could be available in Scotia-Fundy waters. Two experimental licences were approved in 1998 when it was determined that a net benefit to the resource (increase in production of potential spawners) would likely occur if commercial eel fishers ceased fishing adult eels. No additional experimental licences, beyond those already approved, will be considered before a full science review is concluded in 1999. Following that review, if some consideration can be given to new experimental licences, priority will be given to Aboriginal people and aquaculture proponents.


V. CURRENT MANAGEMENT ISSUES

5.1 Bycatch

By-catches have not presented a problem in the elver fishery. The majority of elvers are harvested with dip nets so any incidental catch is immediately apparent and can be released alive. Licence conditions require screening devices in other authorized gear types (elver traps) to prevent other species from entering the gear.

VI. MANAGEMENT MEASURES FOR 1996

6.1 Quota Allocations

Licences which authorize commercial sale will be issued with an initial 1,000 kilogram quota with not more than 300 kilograms generally being permitted from any one river system. (On some rivers, where there is extensive hydro development and poor or no fish passage facilities, more than 300 kilograms is permitted). Licence holders may apply for additional quota (up to a maximum of 30%), of their basic 1,000 kilogram allocation, where they can demonstrate that the initial allocation has been caught. Failure, for biological reasons, to achieve an allocated quota for a period of years may result in reduction of the quota to a level that is more achievable . Except in the area set aside for harvesting for aquaculture purposes, there will be no overlapping fishing areas. In all cases, the licence holder is restricted to fishing only the rivers specified in the licence.

Experimental licences, which only permit harvesting for the purpose of stocking domestic aquaculture facilities, will be issued with a quota commensurate with the capacity of the facility for grow-out. Under no circumstances will that amount exceed 1000 kilograms except under the 30% rule.

6.2 Fishing Seasons

Elvers usually appear in Scotia-Fundy waters from March to August. Licences are normally issued in January/February and are valid from the date of issue to mid-July or August. Usually, elver quantities and condition have declined to non-economic levels by July. Seasons are not used as a significant management tool because the fishery operates on a quota system. In other words, seasons are adjustable to coincide with the elver run.

6.3 Control and Monitoring of Fishing Activities

The elver fishery is controlled by strict licence conditions which set out quotas, control fishing methods and quantity of gear, and require detailed reports on fishing activity which are reviewed annually. Failure to comply with any licence condition may result in its cancellation or suspension. Monitoring of fishing activities is carried out during routine patrols by fishery officers.

In 1997, elver fishers were required, for the first time, to enter into and fund a dockside monitoring program. Dockside monitoring procedures are set out in Appendix 3.

6.4 Other Elements to the 1997/98 Management Plan

6.4.1 Licensing

• Those individuals who held experimental elver licences in 1997 are eligible to renew them in 1998. Terms and conditions for 1998 will be similar to those imposed in 1997. Given that quotas are the overriding management tool for this fishery, some flexibility for gear types may be considered.

• Participation under experimental elver licences is mandatory in 1998 and licence holders must personally fish.

• The area from Halifax/Dartmouth to the Guysborough County line will continue to be set aside for aquaculture stocking.

Licence Reissuance (Transferability)

• Experimental licences may not be reissued to another person.

• Experimental licences will normally become regular licences after four years.

• Once the decision is made to issue regular commercial licences, these licences may not be reissued to another person for a three-year period, at which time reissuance will be reviewed and, if necessary, criteria developed.

• Once the decision is made to issue regular licences which permit harvesting for domestic aquaculture purposes only, these licences will not be eligible for reissuance except where there is a change in the ownership of the aquaculture operation. In the event that an aquaculture operation is unsuccessful, the licence will not be reissued in the subsequent year.

• In the event of the death of either a regular commercial licence holder or the holder of a licence which permits harvesting for aquaculture purposes, the current policy on Disposition of Licence in Case of Death of Licence Holder, will be applied.

Licence Fees

• No fees are charged for experimental licences. The current regulations do not make a distinction between elvers and eels, consequently, the fee for an elver licence and an eel licence are the same - $30.00 annually. Given the value of the elver fishery, and the fact that it is managed as an EA fishery, a separate licence fee needs to be established and reflected in regulation. The current formula for EA licence fees sets a 3% charge for fisheries with landed values up to $50,000 and a 5% charge for those with a landed value in excess of $50,000. This formula will be discussed with licence holders in 1998 in anticipation of regulation amendments for the 1999 season.

• There is a consensus among licence holders that, rather than see large increases in fees, they would sooner provide elvers for enhancement purposes. In particular, they support enhancement on rivers where elver passage is limited or in areas (Gulf of St. Lawrence and Quebec) where elver returns are severely diminished. If licence fee increases become the only option, licence holders feel they cannot support both. As well, given the volatility of prices paid for elvers, a flat rate fee would be preferable to a fee based on dollars per kilogram of quota.

6.4.2 Key Regulations
  • Fishing for eels, which includes elvers, is governed by the provisions of the Fishery (General) Regulations and the Maritime Provinces Fishery Regulations. Essentially, fishing for eels for other than recreational purposes, is prohibited except under a licence. Fishing for eels less than 20 cm in length is also prohibited unless specifically provided for in a licence.
  • The current experimental licences are issued pursuant to section 52 of the Fishery (General) Regulations and conditions are applied pursuant to section 22 of those same Regulations.

VII. CONSERVATION AND PROTECTION ISSUES AND STRATEGIES FOR 1997/98

The natural mortality rate for eels between elver and silver eel stage is believed to be in excess of 95 percent. Harvesting of elvers becomes, essentially, part of the natural mortality at this early life stage and is believed to have less impact on the stock than harvesting at later life stages, particularly the maturing silver eel stage. Given this, and the fact that elver fisheries are believed to be inefficient and are carried out on only a relatively small proportion of the rivers in Scotia-Fundy waters, there is no evidence to suggest that conservation objectives are not being met.

Poaching is a potential threat to the orderly development of the elver fishery. Elvers are particularly susceptible to poaching because a small quantity (2 kilograms) can net a poacher several hundred dollars or more in a night. Such small quantities are easy to conceal and a simple dip net is the only fishing gear required. As the price of elvers has increased in recent years, so have the reports of illegal fishing. This situation has been discussed with licence holders and they are cooperating fully in reporting any suspicious activity in their fishing areas and providing other relevant information.

VIII. INDUSTRY RESPONSIBILITIES

The elver fishery is being developed as an EA fishery. Besides providing economic benefits to licence holders, EA fisheries increase the complexity for management. For example, instead of enforcing one global quota, there are many quotas to track and enforce. For this reason, government has adopted the policy that EA licence holders are required to provide and fund independent, third party monitoring of landings. Following consultations with licence holders in 1996, dockside monitoring was implemented for the 1997 fishery. Dockside monitoring guidelines are set out in Appendix 3.

Given the current fiscal restraints on government, and consistent with the approach taken for developing fisheries, there is an increased onus on fishers to collect and provide information to DFO, particularly information of a science nature. To this end, several licence holders have been funding a Joint Venture Project with DFO since 1996 to study the efficiency of dip net fishing for elvers and to obtain basic life history information.


APPENDIX 1

SCOTIA-FUNDY ELVER ADVISORY COMMITTEE

TERMS OF REFERENCE

1. PURPOSE

The Scotia-Fundy Elver Advisory Committee will provide advice to Fisheries and Oceans Canada (DFO) on the management of the elver resources in inland and tidal waters of the Scotia-Fundy sector of the Maritimes Region. That advice, although not strictly limited, will focus primarily on sustainability of the resource and responsible fishing practices. The Committee will serve as the pre-eminent consultative forum for the development of management measures for elvers in this area.

2. SCOPE

The Committee will provide advice on annual fishing plans, regulatory measures, fishing seasons, licensing policies, size limitations and gear restrictions. It will make recommendations on the introduction of new fishing technologies into the fishery that may affect the existing management measures.

The Committee, after being provided available and pertinent information from the stakeholders and DFO, will give consideration to science, economic, enforcement and other information as it affects the management of the resource.

3. ADMINISTRATION

STRUCTURE

Any change to the structure and administration of the Committee shall be decided by the Committee.

SUBCOMMITTEES

The Committee may establish subcommittees/working groups to review and assess specific policy options and management measures.

MEETINGS

Meetings can be held throughout the Scotia-Fundy sector. Meetings will be held at times and places convenient to the members.

EXPENSES

Committee members will not be reimbursed for expenses incurred for attending Advisory Committee meetings.

DECISION MAKING

No formal voting procedures will be established. The Committee will seek to arrive at a consensus on issues before it. For the purposes of this Committee, consensus means 1. an opinion held by all or most 2. general agreement.

MINUTES OF MEETINGS

Minutes of the Committee´s meetings will be prepared and distributed by DFO unless otherwise directed by the Committee.

PUBLIC ACCESS

All advisory committee meetings held by DFO are open to the public. The Committee may decide to exclude the media.

NUMBER OF MEETINGS

The Committee will meet at least once a year, no later than March. Additional meetings can be held if required at the request of the Committee.

ATTENDANCE

If a member cannot attend, an alternate may be nominated and the Chairperson notified as far in advance of the meeting as possible.

MEMBERSHIP

Chairperson - The Committee will be chaired by the Senior Advisor, Anadromous Fisheries for the Scotia-Fundy sector. At the request of the Committee an industry chosen co-Chair may be appointed.

Membership on the Committee shall be made up of those industry sectors having a vested interest in the conservation and harvest of the resource, as well as Aboriginal representatives and representatives of the provincial governments and DFO.


APPENDIX 2

SCOTIA-FUNDY ELVER ADVISORY COMMITTEE

MEMBERSHIP LIST

Chairman

Greg Stevens

Senior Advisor, DFO

Licence Holders

Wayne Carey

Roland Hamilton

Patrick Gray

Waycobah First Nation

Blair Golden

Alex Troelstra

Philip Holland

Tien Nguyen

Provinces

Ron Cronk

New Brunswick Department of Fisheries and Aquaculture

Bob Crawford

Nova Scotia Department of Fisheries and Aquaculture

DFO

Brian Jessop

Biologist, Diadromous Fish Division

Area Manager

Southwest Nova Scotia

Area Manager

Southern New Brunswick

Area Manager

Eastern Nova Scotia

Keith Veinot

Coordinator, Field Enforcement, C&P

Aboriginal People

Mi´kmaq Fish and wildlife Commission

Native Council of Nova Scotia


APPENDIX 3

SCIENTIFIC ADVICE DOCUMENTS

1Not to be cited without permission of the authors´

DFO Atlantic Fisheries Research Document 95/2

Justification for, and status of, American eel elver fisheries

in Scotia-Fundy Region

by

B.M. Jessop

Biological Sciences Branch

Department of Fisheries and Oceans

P.O. Box 550

Halifax, Nova Scotia

B3J 2S7

1This series documents the scientific basis for the evaluation of fisheries resources in Atlantic Canada. As such, it addresses the issues of the day in the time frames required and the documents it contains are not intended as definitive statements on the subjects addressed but rather as progress reports on ongoing investigations.

Research documents are produced in the offcial language in which they are provided to the secretariat.

Abstract

North America contributes less than 1% to the total world production of eels (Anguillidae) for human consumption. Elvers of the native species have been fished by many coastal nations of Europe (Anguilla anguilla) since the early 1900s, by Japan (A. japonica) since the 1920s, and in various U.S. Atlantic coastal states (A. rostrata) since the 1970s to provide a base for eel culture. In recent years, as the demand for elvers for aquaculture has increased in Japan and Europe and the supply of elvers of local origin has declined, the demand for elvers from North America has increased.

A review of the available evidence on the biology of the American eel and other eel species (many fundamental questions remain) supports the fishing of elvers and other life stages to the extent that the spawning stock is not overexploited. The analysis also indicated economic advantages to fishing elvers, given the current price structure for elvers and larger eels. Although American eels are a panmictic species (a single spawning stock exists, composed of eels from all areas of the species geographic range) and ideally should be managed on a species-wide basis by international agreement rather than by political jurisdiction, conservatively-based management of each life stage of the eel (elver, yellow, silver) on a regional basis is a necessary prerequisite.

Since 1989, the development of elver fisheries in the Scotia-Fundy Region of Nova Scotia and New Brunswick has been encouraged, under tightly controlled conditions, as an opportunity to utilize this stage of the eel resource. The number of potential licences for fishing elvers is tightly limited, each licence covers a specific geographic area. no fishing for elvers is permitted in streams where fisheries exist for larger eels, an overall catch quota is set for each license, catch limits are set for each fishable stream, and a record of daily fishing activity is required. The total elver harvest has increased from 26 kg in 1989 to almost 1.6 t in 1994, with greatest catch in New Brunswick.

Introduction

Annual world production and consumption of eels, Anguilla spp.. has averaged 100,000-120,000 tonnes (t) in recent years (Anon. 1987; Heinsbroek 1991; Gousset 1992). About 70-80% of world production occurs in Japan and Taiwan and is consumed in Japan. Europe produces and consumes the remaining 20-30% of world production. About 15% of European production is cultured. North American production contributes less than 1% to the world total, much of which is exported primarily to Europe.

Regional markets in Europe and Japan prefer the local species of eel (Anguilla anguilla and A. japonica, respectively), although imports of American eels (A. rostrata) to Europe and Japan and A. anguilla to Japan occur where demand exceeds local species supply. High demand for eels and declining catches in Europe have increased interest in the culture of European eels (Heinsbroek 1991). Intensive culture of European eels has had variable success and the number of farms and quantity of production has declined in recent years (EIFAC 1993).

Eel culture uses wild-caught elvers as seedstock and competes with the use of elvers as a food delicacy in some areas. e.g.. the Basque region of Spain. European elvers have been fished since the early 1900s; abundance has declined since the 1940s in Sweden (Hagstrom and Wickstrom 1990) and through the 1980s and early 1990s in Atlantic coastal Europe (Moriarty 1990, 1992; EIFAC 1993). For example, annual elver catches in the Severn River estuary of England once averaged 50-70 t (Bristol Channel Fisheries Ltd., promotional brochure) but have declined to less than 10 t (EIFAC 1993). Recent record low catches have increased European interest in importing elvers from North America. Elver fisheries began during the 1920s in Japan. Declines in Japanese glass eel (unpigmented elvers) abundance during the late 1960s led to imports of European and American elvers during the 1970s and early 1980s but these imports have since declined to very low levels because culture of European and American eels in Japan has generally been unsatisfactory (Gousset 1992). In Japan, about 50-65 t of glass eels are required annually to produce 40,000 t of marketable A. japonica (Gousset 1992).

Eel Life History

American and European eels spawn in the southwestern Sargasso Sea during late winter and early spring (January-April). Spawning areas of both species overlap greatly and occur in or south of the Subtropical Convergence Zone, which is a narrow latitudinal zone of thermal density fronts where water temperatures and density rapidly change (McCleave et al. 1987; McCleave 1993). After hatching, the Florida Current and Gulf Stream carry the willow-leaf-shaped leptocephali larvae north and eastward. Within a year, American eel larvae detrain from the Gulf Stream, presumably via oceanographic processes of eddy diffusion and intrusions of Sargasso Sea water onto the continental slope. McCleave et al. (1987) hypothesize that American eel leptocephali are developmentally ready at this time to metamorphose into glass eels when they encounter the sea bottom during their diel vertical migrations. European eels are hypothesized to have a later and longer window of time for metamorphosis to account for the greater travel distance to Europe. Upon metamorphosis, the leptocephalus becomes a glass eel (unpigmented elver). Glass eels switch from a diel rhythm to a tidal rhythm of vertical migration and use selective tidal stream transport to reach the shore and move up the estuaries of rivers (McCleave and Kleckner 1982). Glass eels in near-shore and instream areas progressively become pigmented and grow into small eels. Most pigmented elvers enter freshwater streams and progressively move upstream into headwater areas if access is possible, but some remain in estuarine and marine conditions. In Scotia-Fundy Region, glass eel arrival varies slightly with geography - in the lower Bay of Fundy N, glass eels first arrive in estuaries at water temperatures of 5-7 °C, usually between late April and mid-May (Groom 1975), whereas along the Atlantic coast of Nova Scotia, elvers typically first arrive between early and late May (Hutchison 1981; Jessop, personal observation). Run peaks may occur 1-2 weeks after first arrival, at water temperatures exceeding 10 °C. By June, most elvers have become pigmented to some degree. In some areas, small numbers of elvers may continue arriving until late July and even August (Sheldon, 1974; Jessop, personal observation). When not engaged in seasonal migration, yellow eels have a relatively small home range, typically with areas about 1-2 ha (LaBar and Facey 1983; Bozeman et al. 1985; Ford and Mercer 1986). After a variable period of time, which may range from perhaps five to twenty or more years in Atlantic Canada depending on growing conditions (Gray and Andrews 1971; Jessop 1987), juvenile (yellow) eels begin sexual maturation, become silver eels, and migrate to sea to complete their adult life cycle by spawning and ultimately dying in the Sargasso Sea. The eel stock of the rivers in Scotia-Fundy Region is primarily female ( > 96% of eels sexually identified; Jessop 1987: Ingraham 1992).

Eel Population Structure

American and European eels are genetically distinct species (McCleave et al. 1987) although hybrids have been found (Avise et al. 1990). Both species are panmictic, i.e., have a single spawning site and random mixing of the gene pool at each spawning (Avise et al. 1986, 1990; Williams and Koehn 1984). Given that larval distribution of each species is essentially random because ocean currents are highly variable, no link has been identified between the river origin of any adult eel and the elvers that enter a river, i.e., no stock-recruit relation for the eel stock (management unit) of any river. At high stock abundance, many commercially-fished marine species do not seem to have a stock-recruit relation (Gulland 1983) but at sufficiently low abundance, a relation develops and recruitment declines with continued overfishing (Hilborn and Walters 1992). American and European eels may have a stock-recruit relation at low stock abundance but data sufficient to test this hypothesis are unavailable. The nature of any relation between spawning eel abundance and elver recruitment to a geographic area is unknown. Nor is there knowledge of the relation between the number of elvers entering coastal areas and the number of spawners produced. Panmixia requires that recruitment variability of the American eel be interpreted at the level of the whole species (Castonguay et al, 1994a). Eggs, larvae, and, to a lesser extent, young marine fishes experience high rates of natural mortality due to predation and adverse environmental conditions and it is likely that similar high mortalities occur to eel eggs, larvae, and elvers. The nature (linear or nonlinear) of the relation between abundance of various life stages is also unknown.

A variety of environmental and human-influenced factors can affect eel survival and growth during marine and freshwater life phases. Factors that might reduce elver/eel stocks include freshwater habitat changes that prevent access to or degrade rearing habitat, an excessive level of commercial harvest, and changes in marine oceanic conditions that reduce spawning success or the distribution of elvers to rivers. Some of these factors have been assessed in relation to the declining stock of American eels in the St. Lawrence River and Gulf with the conclusion that eel life history is too complex to unequivocally determine a cause (Castonguay et al, 1994a). Castonguay et al, (1994b) speculate that the decline through the 1980s of elver recruitment to Europe and to the Gulf of St. Lawrence was due to changes in oceanic conditions, specifically a more northerly position and slower current speed of the Gulf Stream. Recruitment of American eel elvers to rivers south of the Gulf of St. Lawrence appears unaffected. Uncertainty exists as to how much the extensive elver harvesting in European rivers has contributed to subsequent decline in elver recruitment because of the lack of synchrony between the decline and the long history of elver harvesting (Moriarty 1990), the intensive fisheries for yellow and silver eels, the progressive loss and degradation of habitat due to dams and weirs without fish passage, and to water pollution (Tesch 1977; EIFAC 1993).

Obstruction to upstream migration of elvers and small eels may unnecessarily reduce production of adult eels in many Scotia-Fundy streams. No specific guidelines exist to ensure adequate passage of elvers or eels (of any size) through fishways, highway stream culverts, or any other potential obstruction to upstream passage. Movement past natural and man-made obstructions, e.g., fishways and culverts may be prevented by high current flow and vertical waterfalls of even a few cm (Porcher 1992; Legault 1993). The weak swimming ability of elvers and small eels prevents successful use of most fishways, which are designed for strong swimming fishes such as Atlantic salmon. Average swimming speed and peak speed increases with eel size; elvers of about 50-70 mm length have peak swimming speeds of 0.6-0.9 m s-1 and cannot handle water velocities exceeding 0.3-0.5 m s-1 (Porcher 1992; Barbin and Krueger 1994). The movement of eels upriver is greatly slowed and reduced in number if only larger, older eels can pass the typical pool-and-weir fishway and culvert. Fishways may have inter-pool water velocities of 1.6- 1.8 m s-1and a vertical drop between pools of 0.3 m (V. Conrad, Department of Fisheries and Oceans, Halifax, Nova Scotia: personal communication). The ability of eels to bypass obstructions by climbing over nearby wet surfaces may be more illusory than real, with few eels actually succeeding under most conditions. Production of adult eels in Scotia-Fundy Region could be much increased by attention to the specific requirements of eels for upstream passage at fishways, road culverts, and other obstructions. The progressive development of watersheds over time may inadvertently reduce eel habitat to the degree that movement upriver is delayed or prevented. No provisions are made for downstream passage of eels (primarily late summer-autumn migrating silver eels) at hydroelectric dams, with consequent high potential mortality of eels during turbine passage.

Other types of environmental degradation, e.g., acid precipitation and organochloride pollution might also affect eel survival and growth in freshwater, with ultimate effects on harvest and spawning stock size. About one-half of Nova Scotia (southwestern and Atlantic coastal areas) has a geology prone to severe acidification (pH < 5.4) of surface waters via acid precipitation (Watt et al. 1983); the geology of much of New Brunswick is less affected by acid precipitation. American eels are more tolerant of low pH than are many other species, e.g., salmonids, although densities and growth rates may be adversely affected by direct mortalities or declining abundance of prey as productivity declines at low pH. Comparisons of American eel survival and growth under different pH conditions are unavailable. Chemical contamination of eels seems insufficient to produce mortality. Polychlorinated hydrocarbons and pesticides were either undetectable or just above detection limits in American eels from the upper Saint John River, an area of high agricultural use of pesticides and herbicides (Prouse and Uthe 1994).

Justification for an Elver Fishery

The panmictic nature of American and European eel life histones requires coherent stock management on a continental-scale (EIFAC 1993), particularly when exploitation of elver and adult life stages is high. In the absence of continental scale management, local fishery managers must act prudently on a regional and local scale. In the Maritime provinces and Scotia-Fundy Region, exploitation of yellow eels may be sufficiently high in some rivers that signs of overfishing may appear, e.g., sustained decrease in size and quantity of eels caught. Overfishing of an eel stock in a river or lake becomes excessive when it is no longer economically viable; it is not an issue of threat to existence of the stock due to the unique life history of the eel. An unknown, but likely significant, portion of the regional eel stock is unfished or only lightly fished because the small size of many rivers makes fishing uneconomic.

The absence of any link between the eel stock of a river and the recruitment of elvers to it, and the large, widespread, and long-established European fisheries for elvers (notwithstanding the recent declines in European elver abundance) are evidence that a properly managed, moderate-scale fishery for elvers can exist in Scotia-Fundy Region without significant negative effects on regional fisheries for adult eels. The natural mortality rate of elvers during their first year in freshwater (or estuary) is unknown but is likely high, as for the early life stages of most fishes. Mortality rates of 40-60% are common for glass eels cultured over 6-12 months (Heinsbroek 1991); mortality rates of wild fishes usually exceed those of cultured fishes. Elvers caught in a fishery are a pan of the overall mortality, not necessarily an addition to it: that is, most elvers caught in a fishery would likely die of other causes if not harvested. Only when all sources of mortality, including the adult eel fishery, become excessive is there a threat to stock abundance. The elver exploitation rate permissible with minor or no detectable effect on adult eel abundance is unknown, but elver exploitation rates of less than 25-30% may have minor effect relative to a high natural mortality rate. The exploitation rate for adult eels allowable over the geographic distribution of the species that is sufficient to maintain a spawning stock capable of producing some critical level of continent-wide elver distribution is also unknown. Natural mortality rates for larger American eels are also unknown. Whether elvers or larger yellow or silver eels are exploited is biologically immaterial (both are pre-spawning stages) as long as catch rates for each life stage are kept within limits that will not produce overfishing of the spawning stock. Determination of these limits will be difficult, perhaps impossible, and may only be evident after overharvesting has occurred. This does not imply that rational, conservative limits cannot be set based on existing knowledge.

Economics may be the deciding criterion, given no biologically best (from a stock perspective) stage at which to harvest eels. The economic justification for harvesting elvers rather than larger (yellow, silver) eels was evaluated under the following conditions: 6,500 elvers/kg, a mean eel size of 250 g (4/kg) and 10 years of age at capture (growth rate 25 g yr-1; Jessop 1987), an elver survival rate during the first (arrival) year ranging from 0.4 to 0.7 (high elver survival rates are unlikely and may be lower than assumed here), and an annual eel survival rate increasing (in increments of 0.5, under the assumption that annual eel survival rate increases with age) ranging from 0.4 to 0.6 in year 2 to a maximum of 0.8 in annual increments of 0.05, then remaining constant, over a 10 year life span before harvest (total elver-eel mortality rates from 0.43 to 0.68), elver prices ranging from $100-$300/kg, and eel prices ranging from $2.75-$3.85/kg (a large increase in price for elvers is more likely than for eels). Under Scenario 1, which assumes a lower initial survival rate (higher mortality rate) for eels, profits were highest catching elvers rather than larger eels. Thus, even at the highest elver survival rate (0.70) and a total elver-eel mortality rate of 0.52 over a 10 year life span, harvesting elvers yielded $15,385 at the lowest elver price of $100/kg as compared with $5,462 for eels at the highest eel price of $3.85/kg (Table 1). The elver and eel mortality rate assumptions are most critical to the outcome of the model; increased survival rates for either/both elver and larger eels and higher growth rates for larger eels are necessary to make eel fishing more economically beneficial than elver fishing. Under Scenario 2, an increased initial survival rate (decreased mortality rate) resulted in changing advantage for elvers versus eels, depending upon the specific mortality rates and price/kg for elvers and eels. If it is assumed that the average price/kg for elvers is more likely to equal or exceed $200/kg than the average price/kg for eels is to reach $3.85/kg, then fishing for elvers is equally or more economically profitable than fishing for eels.

Catch data accumulated from experimental fisheries is essential for assessing the potential elver yield of streams of various size and geographic location and the prospects for developing an economic, sustainable fishery. The abundance of elvers entering any river is unknown; it is presumed to be proportional to river size and may vary annually and regionally due to stock and environmental factors. The total annual return of elvers to the East River, Sheet Harbour (drainage area 526 km2; mean May-June discharge 16 m3 s-1, Environment Canada 1991) between 1990 and 1994 has averaged 251,900 elvers (range 134,100-376.000) or about 48 kg in weight.

Run sizes to other rivers may be estimated by extrapolation from the East River data, assuming that the run size-river size relation is linear (unlikely), the availability of elvers from offshore is similar among geographic areas, and that the mean May-June discharge (or drainage area) is an appropriate indicator of elver attraction by a river. Elvers are attracted to streams by a preference for freshwater which contains the odours of decaying leaf detritus, aquatic plants, and migrating alewives and, less so, eel odour (Sorensen 1986; Tosi et al. 1990), which may vary among streams. Thus, the elver run to the Saint John River, New Brunswick (based on the area upriver of, and discharge at the Mactaquac Dam, which underestimates values for the total drainage basin, can be estimated by linear extrapolation as 19.0 million (based on drainage area) to 24.8 million (based on discharge). Given 6,500 elvers/kg and a harvest efficiency of 25%, about 730-950 kg of elvers could be harvested from the Saint John River, if permitted. The drainage area (discharge is unavailable for many rivers) of rivers in the Scotia-Fundy Region totals about 94,800 km2 which, by proportion, could have a total elver run of about 45.4 million elvers weighing 7.0 t. These quantities are small relative to the runs and harvests of elvers in European areas, where annual harvests of about 50-70 t were taken from the Severn River in England, over 100 t from the Loire River in France, and 23 t from the River Bann in Northern Ireland (Bristol Channel Fisheries Ltd., promotional brochure; Monarty 1990), all of which are smaller than the Saint John River. Of course, the abundance of elvers arriving at a river need not be similar among species and continents but such wide disparity is unexpected. If the relation between river size and elver run size is nonlinear, the assumption of a linear relation could greatly underestimate run sizes of larger rivers. The East River may not be a good base from which to extrapolate elver returns for other Maritime province rivers: it has a low discharge, a discharge low for its drainage area, a moderately low pH, it may be less attractive to elvers than rivers with better environmental quality, and current patterns may bring fewer elvers to Atlantic coastal regions of Nova Scotia than to the lower Bay of Fundy. Annual elver harvests from rivers such as the Musquash (50 kg) and Magaguadavic (150 kg) of southwest New Brunswick presently approximate the projected total return based on drainage area (Musquash River 389 km2; Magaguadavic River 1,812 km2), yet dip net fisheries are naturally inefficient. Linear extrapolation of the catch-river basin area relation for the Musquash and Magaguadavic rivers provides an estimate of potential harvest of 3.2 t from the Saint John River, which may be more realistic than the 730-950 kg previously estimated. I conclude that insufficient data presently exists to reliably estimate the potential run of elvers to other Scotia-Fundy rivers. The run of elvers to the East River, Nova Scotia may be most useful as an index of annual variability in elver run size to Atlantic coastal streams of Nova Scotia and a source of data on the biological characteristics of elvers.

Status of the Elver Fishery

Increased demand for elvers in Europe and Japan and the desire of Canadian freshwater fishers to diversify in response to declines in traditional fisheries led to granting the first experimental license in Scotia-Fundy Region in 1989. That license permitted elver fishing in southwestern New Brunswick and prohibited elver fishing in rivers and estuaries where fisheries for adult eels exist. Since then, three other licenses have been issued to fish in Nova Scotia and New Brunswick. Experimental licenses have also been requested to fish the Eastern shore of Nova Scotia and the Scotia-Fundy portion of Cape Breton. Licences to fish elvers are issued under Section 52 of the Fishery (General) Regulations, of which Section 38(1) of the Maritime Provinces Fishery Regulations otherwise prohibits the catch and retention of eels less than 20 cm long in Nova Scotia and New Brunswick. A variety of provisions is attached to each license. including specific limitations as to the geographic area and rivers to be fished, the type of fishing gear permitted (generally dip net, but also including Sheldon and other types of elver traps, fyke nets, and elver trawls), numbers of each gear type other than dip net, provisions for live return of bycatch, an overall catch quota of, usually, one tonne with possible limits on the quantity from any specific river, and a requirement to maintain and submit at seasons end a record of daily fishing activity and catch.

The elver fishery in Scotia-Fundy Region has developed steadily for the past six years as fishers developed familiarity with proper fishing methods and gear, explored potential fishing sites, developed holding and shipping methods, and established markets for their catch. The total elver harvest has increased from 26 kg in 1989 to almost 1.6 t in 1994, with greatest annual production usually from New Brunswick (Table 2). Additional detail on the geographic and river distribution of catch has not been given because this would enable identification of landings by licensee and release of such data is prohibited by the Access to Information Act. Elver exploitation rates in any river are believed low because elver fishing techniques are relatively inefficient and not yet intensively applied.

Elver and small eel fisheries have intermittently occurred since the 1970s in several US Atlantic coastal states, particularly Maine (Fahay 1978: Gousset 1992; L. Flagg, Maine Department of Marine Resources, Augusta, personal communication). Catch statistics for US elver fisheries were not routinely kept by some states and are unavailable. The reported 1994 catch of elvers in Maine was 3.0 t. about 40% of which was taken from the coastal region between the New Hampshire border and the Kennebec River, 40% between the Kennebec and Penobscot rivers and 20%, between the Penobscot River and the Canadian border.

Summary and Conclusions

The biological information presented suggests that a properly managed fishery for American eel elvers in Scotia-Fundy Region will be biologically sustainable because it will have little impact on regional eel abundance and consequently on spawning stock size. Prohibition of elver fisheries where existing fisheries occur for adult eels will prevent conflict between modes of exploitation. A preliminary economic analysis indicates that harvesting elvers rather than larger eels may be economically advantageous. Catches from the elver fishery indicate that elver returns to smaller rivers are insufficient to support an elver fishery alone and the rivers fished must be grouped regionally to be economically viable. The potential number of elver licenses is limited; the number already issued and those few under consideration for unfished regions are perhaps sufficient to exploit the available resource.

Acknowledgements

I thank M. Castonguay and L. Marshall for helpful comments on early drafts of this report and C. Harvie for assistance in setup of the economic analysis spreadsheet.

References

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Castonguay, M., P. V. Hodson, C. Moriarty, K. F. Drinkwater, and B. M. Jessop. 1994b. Is there a role of ocean environment in American and European eel decline? Fish. Oceanogr. 3: 197203.

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Watt, W. D., C. D. Scott, and W. J. White. 1983. Evidence of acidification of some Nova Scotian rivers and its impact on Atlantic Salmon, Salmo salar. Can. J. Fish. Aquat. Sci. 40: 462473.

Williams, G. C., and R. K. Koehn. 1984. Population genetics of North Atlantic catadromous eels (Anguilla), p. 529560. In B. J. Tumer [[ed.] Evolutionary genetics of fishes. Plenum, New York, N.Y.

Table 1. Economic evaluation of elver versus eel harvest - the value at specified market prices of elvers and of eels surviving from those elvers, given the assumption of a harvest of 1,000,000 elvers, 6,500 elvers/kg, a life span of 10 years between elver and harvested eel, a harvest weight of 250 g/eel (4 eels/kg), and two scenarios for the pattern and rate of eel annual survival: Scenario 1 - initial eel survival rate 0.4; Scenario 2 - initial eel survival rate 0.6.

Value/kg

$100

$200

$300

Value ($) of 1,000,000 elvers

15,385

30,769

46,154

Scenario 1

Scenario 2

Eel price/kg

Eel price/kg

Elver Survival Rate

# of eels

Total mort-
ality

$2.75

$3.85

# of eels

Total mort-
ality

$2.75

$3.85

(yr 1)

(yr 10)

(Z)

Catch value
($)

(yr 10)

(Z)

Catch value
($)

0.70

5,676

0.52

3,902

5,462

46,965

0.31

32,288

45,205

0.60

4,865

0.53

3,344

4,683

40,256

0.32

27.676

38,745

0.50

4,054

0.55

2,789

3,902

33,546

0.34

23,064

32,288

0.40

3,243

0.57

2,230

3,121

26,837

0.36

18,450

25,831

Table 2. Annual catches (kg) of American eel elvers in Scotia-Fundy Region, by province, 1989-1994.

Year

New Brunswick

Nova Scotia

Total

1989

0

26

26

1990

132

42

174

1991

65

0

65

1992

227

0

227

1993

534

156

690

1994

650

934

1,584


1Not to be cited without permission of the authors´

DFO Atlantic Fisheries

Research Document 95/04

Review of the American eel elver fisheries

in Scotia-Fundy, Maritimes Region

by

B.M. Jessop

Biological Sciences Branch

Department of Fisheries and Oceans

P.O. Box 550

Halifax, Nova Scotia

B3J 2S7

1This series documents the scientific basis for the evaluation of fisheries resources in Atlantic Canada. As such, it addresses the issues of the day in the time frames required and the documents it contains are not intended as definitive statements on the subjects addressed but rather as progress reports on ongoing investigations.

Research documents are produced in the official language in which they are provided to the secretariat.

Abstract

The fishery for American eel (Anguilla rostrata) elvers in Scotia-Fundy Region has, since its inception in 1989, increased the number of experimental licenses to seven, with each license operating within separate, defined geographic areas, and increased catches from 26 kg to 3.2 tonnes, worth an estimated 1.62.2 million dollars.

Elver catches (presumed to reflect elver abundance) varied geographically and between years. In 1995, elver catches were highest along the lower Bay of Fundy and South Shores of Nova Scotia, moderately high along the lower Bay of Fundy (southwest) shore of New Brunswick and scarce along the Eastern Shore of Nova Scotia. In 1994, elver catches were higher in southwest New Brunswick than along the Fundy and South Shores of Nova Scotia. Elvers first arrive in April but most elver catch occurs during May. The higher proportion of May elver catch occurring in southwest New Brunswick relative to the lower Bay of Fundy shore of Nova Scotia reflects the counterclockwise movement of elvers through the Bay of Fundy in response to residual currents.

Refinements to the existing management plan are being considered for 1996 with the objective of promoting full geographic coverage by the fishery and providing for native and aquaculture requirements.

Introduction

No fundamental changes have occurred in or to the fishery for American eel elvers (Anguilla rostrata) in the Bay of Fundy and Atlantic coastal areas of Nova Scotia (formerly the Scotia-Fundy Region) since the review by Jessop (1995). That review provides the necessary background information on eel biology and a biological and economic justification for an elver fishery. The high interest in the development and progress of this fishery and the ongoing development of management policy justifies an update on the status of this fishery which will be provided by this report.

Elver Fishery

Active fishing for elvers during 1995 remained confined to the former Scotia-Fundy Region, although the former Gulf Region (both regions have recently been amalgamated into a single Maritimes Region) issued an experimental permit for test fishing in the Miramichi River estuary. The Gulf Region fishery was unsuccessful largely due to a restriction on where the fishing could occur. Catches of elvers in Scotia-Fundy Region more than doubled from 1,574 kg in 1994 to 3,238 kg in 1995 (Table 1). About 72 kg (2.2%) of the elver catch was used for aquaculture in New Brunswick. Most (5 of 7) fishers did not achieve their quota of 1,000 kg (except 5 kg for one new licensee fishing for aquaculture) in 1995 for reasons ranging from operational difficulties to lower elver availability in some areas. Two fishers achieved their initial quota and were granted extensions of up to 300 kg; neither extension was fully met.

Catches (Table 1) cannot be presented by geographic area, e.g., southwest New Brunswick, upper Bay of Fundy N.B. and N.S., lower Bay of Fundy N.S., south shore N.S., etc. because the Access to Information Act prevents public release of catch data that may be linked to individual fishers. The following discussion avoids presentation of detailed catch or other data where fisher identification might occur but reported observations may be based on such detailed analysis.

Market prices for elvers fluctuate substantially between years and throughout the fishing season. In 1995, reported (L. Flagg, Maine Department of Marine Resources, personal communication) prices for elvers paid by U.S. buyers (most Canadian elver catches are sold to U.S. buyers or at comparable market prices) averaged about $685 Canadian/kg and ranged between about $240 and $1000/kg while a Canadian fisher reported average prices of $500 Canadian/kg. At average prices, the 1995 elver fishery grossed between $1.6 and $2.2 million dollars.

The increased fishing activity in recent years and the expansion of the fishery to several new areas has begun to produce information sufficient for basic analysis of seasonal and regional patterns of elver catch. It is assumed that, given sufficient fishing effort in each fishing area throughout the period of elver arrival, catches will reflect elver abundance.

Prior to 1995, the largest annual elver catches occurred in the lower part of the Bay of Fundy on both the New Brunswick and Nova Scotia sides. Catches were largest from the southwestern New Brunswick side of the Bay of Fundy, but the fishing effort (no effort statistics are available) is believed to have been greatest there also. In 1994, significant fishing effort began in the Nova Scotia portion of the upper Bay of Fundy and along the South Shore of Nova Scotia´s Atlantic coast. In 1995, an exploratory fishery began in Guysborough County on the Eastern Shore area of Atlantic coastal Nova Scotia. According to observations and reported catches by the elver fishers, the abundance of elvers arriving in different geographic areas in 1995 differed from that in 1994, with a decreased abundance of elvers in Southwest New Brunswick, few elvers along the Eastern Shore of Nova Scotia, and greater abundance along the Nova Scotia shore of the lower Bay of Fundy and the South Shore of Nova Scotia. These observations imply annual variability in the geographic distribution of elver abundance (fishing effort is believed to have been roughly similar in each area between years). Annual variations in elver abundance in an index river may reflect conditions only in a limited geographic area. Several appropriately distributed index rivers may be required to draw inferences from a wide geographic area.

Estimates of fishing effort in 1995 were obtained from several elver fishers to assist interpretation of the catch data (Table 2). The estimates of fishing effort were obtained several months after the end of the fishing season on a "best remembrance" basis since only daily catches from each river had originally been requested. Consequently, the effort data are of somewhat uncertain and variable accuracy. Catch per unit effort (CPUE) differed among areas (F3,39 = 3.42, P < 0.03; CPUE values logarithmically transformed) with the CPUE for the South Shore of Nova Scotia being lower than that from the other areas. It is believed that the effort reported from the South Shore area is overestimated and that CPUE was basically similar in all areas. Given this condition, one might conclude that regional catches depend simply on the effort expended. The fishers would reject this interpretation because the actual effort expended fishing depends, in a feedback loop, on the quantities of elvers available. Thus, if no elvers are present after an initial survey of the river on a given night, no further time is spent there and another river may be visited or fishing suspended. The similar CPUEs among areas may imply that, when elvers are present, their catchability by dip-net is similar among regions. Differences in catches among areas thus reflect differences in elver abundance among areas. In all years, most catches (66-88%) occurred in May in all areas (Table 3). The high monthly variability in catch reflects the historical development of the elver fishery and seasonal variability in elver abundance. Elvers first arrive in late April or early May, depending upon the area, peak in May, and decline to negligible commercial quantities in, or before, early June. Small quantities of elvers may continue to enter streams, e.g., East River, Sheet Harbour, through July (Jessop, unpublished data). The proportion of catches occurring in May was consistently highest in the lower Bay of Fundy, New Brunswick (8%), then decreased in a clockwise fashion through the upper Bay of Fundy, N.B. (82%), upper Bay of Fundy, N.S. (78%), and lower Bay of Fundy, N.S. (63%). Elver catch proportions were similar (63%) during May in the lower Bay of Fundy and South Shore areas of Nova Scotia. The pattern and speed of coastal water currents and rising spring freshwater temperatures may play major roles in the coastal distribution and entrance of elvers to rivers. The arrival of elvers throughout the Bay of Fundy progressed in counterclockwise fashion from the lower Bay of Fundy, Nova Scotia, to Southwest New Brunswick consistent with the counterclockwise pattern (and probably velocity) of residual water currents in the Bay of Fundy (Greenburg 1984). American shad (Alosa sapidissima) migrate in a similar manner through the Bay of Fundy (Dadswell et al. 1983). Increasing river water temperatures may provide the first cue for elvers to enter rivers (Martin 1995) and river temperatures usually warm sooner along the south shore and lower Fundy shore of Nova Scotia than elsewhere in the Maritimes. Early elver arrivals to the lower Bay of Fundy may progress around the Bay until water temperatures rise sufficiently to cue river entrance.

Management Regulations

Refinements continue to be made to existing management principles and regulations (G. Stevens, Resource Management Branch, personal communication). Seven experimental elver fishing licences presently exist for different geographic areas of the Scotia-Fundy Region, five of which permit commercial sale, while two prohibit direct sale and are to be used for aquaculture. Four areas are not covered by experimental licences - Shelburne/Yarmouth Counties, Halifax County from Dartmouth to the Guysborough County line, Cape Breton Island, and a small sector of Minas Basin shore from Cape Chignecto to Debert River.

Experimental licences are issued for a specific purpose, have no guarantee of renewal, and may contain a variety of restrictions, such as specification of the rivers permitted to be fished, catch quota, permissible gear, weekly closed fishing period, and bycatch release provisions. A regular licence, once issued, is annually renewable upon application and is restricted only by the provisions allowable under the Canada Fishery Regulations (General and Maritime). Present policy prohibits issuance of an experimental elver licence for the Shelburne/Yarmouth County area because all rivers have existing fisheries for adult eels. Consideration is being given to issuing licences for the remaining unlicensed areas in 1996.

Each commercial fishery licence and one aquaculture licence has arbitrarily, but with rough biological justification, been allocated a catch quota of 1,000 kg (one aquaculture licence was issued a trial 5 kg quota), with consideration given to an extension of 300 kg if the initial quota is achieved. Catch quotas usually limit exploitation to biologically and managerially acceptable levels. Exploitation rates of 40-60% are often viewed as acceptable but the issue is moot when population size cannot or has not been measured. Elver recruitment to a river is usually unknown as is the population of large eels in, or the spawning escapement of silver eels from, any river. Insufficient information exists to set biologically meaningful catch quotas for elvers or larger eels. A quota set on an arbitrary but best judgement basis seems preferable to no quota, as for yellow and silver eels, although stage (elver, yellow, silver eel) and area (estuarine, freshwater) of exploitation (but not degree of exploitation) is irrelevant for eels. It might be argued that the elver fishery quota should be proportional to the fishing area, on the assumption that elver abundance is proportional to the drainage area or discharge of a river or series of rivers in the licensed fishing area. Evidence presented above suggests that the assumption is false that annual elver recruitment is of similar density or abundance over wide geographic areas and among years. Drainage areas for the Scotia-Fundy portions of New Brunswick total about 65,400 km2 and for mainland Nova Scotia (excluding Cape Breton) total about 37,800 km (Maritime Resource Mapping Service, Amherst, N.S.). Elver fishing is licensed for about 17% and 32%, respectively, of the total drainage area in the Scotia-Fundy portions of New Brunswick and mainland Nova Scotia, for combined elver fishing area of 23% of the total drainage area. Individual fishers exploit an average of 57% (range 24-100%) of the total drainage area in their licensed territory. It is, I believe, premature to adjust an arbitrary catch quota on the basis of fishing area, particularly when changes to elver fishery quotas are likely to have minimal effect relative to the potential (many licences for large eel fisheries are unused and existing gear allowances are often unfished) for fishing effort to increase greatly in the fishery for larger eels. Adjustments to the exploitation rates for eels in a river or geographic area should consider all life stages and the economics of each fishery.

Eligibility criteria for new elver licences are being developed within Fisheries Management Branch and may be implemented in a public call for new applications where competing applications have been made for licences in some of the presently unlicensed areas. The new eligibility criteria will accommodate native fisheries, CORE eligible fishers, and requirements of the aquaculture industry. Other changes being considered include the conversion of some experimental fishing licences to regular fishing licences and implementation in 1996 of a formal log book system to collect data on daily catch and fishing effort for each river fished.

Summary and Conclusions

The elver fishery in Scotia-Fundy Region has grown substantially in the past four years as fishers have refined their skills in catching and handling elvers and their knowledge of the elver runs to various rivers within their licence area. The present annual doubling of catch is unlikely to continue much longer because fewer areas remain to be exploited and those areas may prove to be less productive than the best areas presently fished. The data from DFO research projects, e.g., at East River, Sheet Harbour, and the annual catch records of the fishery permit an improved understanding of the biological characteristics of elvers entering Scotia-Fundy Region rivers and the annual variability in elver abundance among geographic areas. Proposed regulatory changes will further stabilize the fishery.

References

Dadswell, M. J., G. D. Melvin, and P. J. Williams. 1983. Effect of turbidity on the temporal and spatial utilization of the inner Bay of Fundy by American shad ( Alosa sapidissima ) ( Pisces: Clupeidae) and its relationship to local fisheries. Can. J. Fish. Aquat. Sci. 40: 322330.

Greenburg, D. A. 1984. A review of the physical oceanography of the Bay of Fundy, p. 9-30. In Gordon, D.C. Jr. and Dadswell, M.J. Update on the marine environmental consequences of tidal power development in the upper reaches of the Bay of Fundy. Can. Tech. Rep. Fish. Aquat. Sci. No. 1256. 686 p.

Jessop, B. M. 1995. Justification for, and status of American eel elver fisheries in Scotia-Fundy Region. DFO Atl. Fish. Res. Doc. 95/2. 10 p.

Martin, M. H. 1995. The effects of temperature, river flow, and tidal cycles on the onset of glass eel and elver migration into fresh water in the American eel. J. Fish. Biol. 46: 891-902.

Table 1. Annual catch (kg) of American eel elvers in Scotia-Fundy area, by province, 1989-1995.

New

Nova

Total

Fishery

Year

Brunswick

Scotia

Catch

Quota

1989

0

26

26

2,000

1990

132

42

174

2,000

1991

65

0

65

2,000

1992

227

0

227

3,000

1993

534

179

713

4,000

1994

650

924

1,574

4,000

1995

549

2,689

3,238

6,005

Table 2. Catch and fishing effort by the dipnet fishery for American eel elvers in ScotiaFundy area, 1995.

Catch per hour

Area

Na

MeanD

SD

Lower Bay of Fundy, N.B.

9

0.74

0.37

Lower Bay of Fundy, N.S.

7

0.61

0.26

South Shore, N.S.

9

0.33

0.30

Eastern Shore, N.S.

18

0.75

0.65

Na is the number of daily catch and effort estimates.

bThe mean determined from individual catch/effort (c/e) values does not equal

the c/e value determined from total catch and effort because individual c/e

values are not additive and are non-normally distributed.

Table 3. Monthly percentages of annual total catch of American eel elvers in geographic areas, in Scotia-Fundy area, 1990-1995.

Area

Month

N

Mean (%)

Range (%)

Lower Bay of Fundy, N.B.

April

5

1

0.1-4

May

5

88

52-98

June

1

11

2-44

Upper Bay of Fundy, N.B.

April

2

5

May

2

82

71-97

June

3

13

3-19

Lower Bay of Fundy, N.S.

April

5

25

9-35

May

1

63

33-66

June

2

12

South Shore, N.S.

April

2

36

19-43

May

1

63

57-79

June

1


APPENDIX 4

DOCKSIDE MONITORING GUIDELINES

FOR THE ELVER FISHERY

The following dockside monitoring procedure is to be followed for the elver fishery.

1. On each day that elvers are caught and retained, the licence holder must call a Dockside Monitoring Company (DMC) approved by Fisheries and Oceans Canada (DFO) and provide that company with the total catch weight of elvers for that day.

2. When sufficient elvers have been accumulated and a shipment to a buyer is to be made, the licence holder will notify the DMC and an observer will be sent to monitor the weight of elvers shipped. For licence holders who are not shipping elvers but retaining them for aquaculture purposes, the elvers must be held in a separate tank until a sufficient quantity has been accumulated to justify monitoring. At that time the licence holder will notify the DMC and an observer will be sent to monitor the weight of elvers being moved from the separate tank into grow-out tanks.

3. A statement or receipt of the shipped weight of elvers signed by both the observer and the licence holder will be retained by the licence holder.

4. The DMC is to maintain a record of the weighouts and supply them to DFO upon request and at the end of the elver fishing season.

5. To minimize injury and unnecessary mortality, all weighings will be done wet, using a mesh bottomed container to permit drainage.

6. The container should first be weighed dry to determine the tare weight for later weighings.

7. A correction factor of 25% of the wet weight is to be applied to the dry weight to adjust for water adhesion and the “dry equivalent” weight of the elvers is to be recorded.

Specific Weighing Procedures

a) Check scale for accuracy at the beginning of weighing.

b) Fill mesh bottom container with elvers and shake out excess water.

c) Record the weight.

d) At the end of weighing, deduct 25% for water weight which will give the dry “true” weight of elvers being shipped.

Example: 100 kg x 25% kg to be deducted for a total weight of 75 kg.




Last Modified : 2003-01-31