k mae 199834901

Bull. Fr. Pêche Piscic. (1998) 349:103-116 — 103 —

T H E M A N A G E M E N T OF, A N D FISHERY FOR, A M E R I C A N E E L ELVERS IN T H E M A R I T I M E PROVINCES, C A N A D A .

B . M . J E S S O P

Bio log ica l Sc iences B r a n c h , D e p a r t m e n t of F isher ies a n d O c e a n s ,

P.O. Box 550 , Hal i fax, Nova Sco t ia , B3J 2 S 7 , C a n a d a .

A B S T R A C T

The f i shery for A m e r i c a n ee l , Anguilla rostrata, e lvers in the Sco t i a -Fundy area of

At lant ic C a n a d a has, s ince incept ion in 1989 , i nc reased ca t ches f r o m 2 6 kg to about

3 000 kg in 1996. Deve lopmen t of the f i shery has b e e n t ight ly con t ro l led w i th n ine l i censes

present ly (1996) i ssued , th ree of w h i c h a re rest r ic ted to aquacu l t u re use . N o elver f ishery

is permi t ted in r ivers in w h i c h an act ive f i shery for larger ee ls ex is ts , e a c h l i cense has a

quo ta of up to 1 t on , w i th a l imit of 3 0 0 kg f r om any g iven river, a n d reco rds of da i ly catch

a n d f ish ing effort, by gear t ype , a re n o w requ i red for each r iver f i shed .

Elver ca tches and C P U E va ry geograph ica l ly , be ing h ighes t a l o n g the sou th shore

and lower Bay of Fundy a reas of Nova Sco t ia , modera te l y h igh a l ong t h e lower Bay of

Fundy, N e w Brunswick , a n d lowest a l ong the eas te rn shore of Nova Sco t ia a n d uppe r Bay

of Fundy a reas (M inas Bas in a n d C h i g n e c t o Bay) . In al l a reas but the eas te rn shore of

Nova Scot ia , commerc i a l quant i t ies of e lvers first arr ive in Apr i l . E lver ca t ch p e a k s dur ing

May, t hen dec l ines t h rough J u n e w i th sma l l ( less than 1 % of tota l ) ca t ches occur r ing in

s o m e a reas du r ing ear ly July. G e o g r a p h i c d i f fe rences in e lver ca t ches a n d run t i m i n g may

be l inked to océanog raph ie cur rent pa t te rns , par t icu lar ly the s o u t h w e s t w a r d f low of t h e

Nova Scot ia Cur ren t a l ong the At lant ic coas t and the coun te r - c lockw ise f low a r o u n d the

Bay of Fundy, and d i f fe rences in the t im ing of r is ing r iver wa te r t e m p e r a t u r e s du r ing spr ing.

Elver run s ize w a s not p ropor t i ona l to river s ize (d ra inage a rea ) for t w o r ivers f rom

di f ferent geograph ic a reas nor w a s e lver f i shery ca tch-per -un i t - f i sh ing effort p ropor t iona l to

r iver d ra inage a rea , pe rhaps b e c a u s e of geograph ic d i f fe rences in e lver densi ty.

K e y - w o r d s : f ishery, Anguilla rostrata, e lvers , At lant ic C a n a d a .

L A G E S T I O N D E , E T P Ê C H E P O U R , L E S C I V E L L E S D E L ' A N G U I L L E D ' A M É R I Q U E

D A N S L E S P R O V I N C E S M A R I T I M E S D U C A N A D A .

R É S U M É

La pêche des c ive l les de l 'angui l le d 'Amér ique , Anguilla rostrata, d a n s la région de

Scot ia -Fundy, au C a n a d a a t lan t ique , a, depu i s ses débu ts en 1989 , c o n n u une hausse d e s

cap tu res , qu i de 26 kg son t p a s s é e s à env i ron 3 0 0 0 kg e n 1996. Le d é v e l o p p e m e n t de

cet te pêche a été gé ré de façon s t r ic te . O n c o m p t e ac tue l l emen t neuf p e r m i s e n 1996,

don t t ro is sont réservés à l ' industr ie de l 'aquacu l ture . Il est interdi t de pêche r des civel les

d a n s d e s r iv ières où est p ra t iquée ac t i vemen t une pêche d e s p lus g r o s s e s angui l les . Par

a i l leurs, c h a q u e pe rm is est assor t i d 'un quo ta max ima l d ' une t o n n e , la l imite par rivière

é tant de 300 kg , et les pêcheu rs do iven t fourn i r d e s re levés de leurs p r i ses quo t id iennes et

de leur effort de pêche , par t ype d 'eng in , d a n s c h a q u e r iv ière où ils on t p é c h é .

Article available at http://www.kmae-journal.org or http://dx.doi.org/10.1051/kmae:1998036

http://www.kmae-journal.org

http://dx.doi.org/10.1051/kmae:1998036

Bull. Fr. Pêche Piscic. 0998) 349 :103-116 — 104 —

Les p r i ses de c ive l les et les P U E varient se lon la rég ion . El les sont les p lus é levées

le l ong de la côte s u d et de la par t ie infér ieure de la baie de Fundy en Nouvel le-Ecosse,

a s s e z é l e v é e s le l ong de la par t ie infér ieure d e la baie de Fundy au Nouveau -B runsw ick et

p lus b a s s e s le long d e la cô te est de la Nouvel le-Ecosse et de la par t ie supér ieu re de la

ba ie de F u n d y (bass in des M i n e s et baie Ch ignec to ) . Sauf sur la côte est de la Nouve l le -

Ecosse, les c ivel les c o m m e n c e n t à arriver en quant i tés c o m m e r c i a l e s dans tous les

s e c t e u r s en avr i l . Les p r i ses cu lm inen t en ma i , puis d im inuen t en ju in . Des pet i tes

q u a n t i t é s (mo ins de 1 % du tota l ) de civel les sont cap tu rées dans cer ta ins sec teurs au

d é b u t d e ju i l let . Les va r ia t ions géog raph iques dans les pr ises et les remontées peuvent

ê t re re l iées aux r é g i m e s de c o u r a n t s océan iques , par t i cu l iè rement au couran t de la

Nouve l le -Ecosse e n d i rec t ion sud -oues t , le l ong de la côte a t lan t ique, et au couran t rotatif

d e d ro i te à g a u c h e le long de la ba ie de Fundy, a ins i qu 'à d e s d i f fé rences dans la pér iode

d ' é l éva t i on d e s t empé ra tu res de l 'eau des r iv ières au p r in temps .

L ' impor tance d e s r e m o n t é e s des civel les n'était pas p ropor t ionne l le à la tai l le de la

r i v iè re ( zone de d r a i n a g e ) , pour d e u x r ivières de d i f fé rentes zones géograph iques , de

m ê m e q u e les pr ises par un i té d 'ef for t de p ê c h e de la p ê c h e aux c ivel les n 'étaient pas

p r o p o r t i o n n e l l e s à la zone de d ra i nage de la r iv ière, peut -ê t re en raison de d i f fé rences

g é o g r a p h i q u e s dans la dens i t é d e s civel les.

M o t s - c l é s : p ê c h e , Anguilla rostrata, c ive l le , C a n a d a a t lan t ique.

I N T R O D U C T I O N

H i g h d e m a n d for, a n d con t i nu ing shor tages of, e lvers of Anguilla japonica in As ia

a n d A. anguilla in E u r o p e for aquacu l tu re has gene ra ted prof i table expor t marke ts for

e l ve rs of A. rostrata f r o m Nor th A m e r i c a to, pr imari ly, As ia . F isher ies for A m e r i c a n eel

e l ve rs have occu r red w i th va ry i ng , market -dr iven intensi ty in several At lant ic coas t U.S.

s t a tes s i n c e the ear ly 1 9 7 0 s (FAHAY, 1978 ; G O U S S E T , 1992) . S ince 1989, elver

f i she r i es have p rogress ive ly deve loped in the Bay of Fundy and At lant ic coasta l a reas of

N e w B r u n s w i c k (N.B.) a n d Nova Sco t i a (N.S.), t e r m e d the Sco t ia -Fundy area, and are

p r e s e n t l y the only s u c h f i sher ies occu r r i ng in At lant ic C a n a d a (JESSOP, 1995 ; 1996a) .

E L V E R F I S H E R Y M A N A G E M E N T

In 1989 , the f irst t w o l i censes we re i ssued to f ish exper imen ta l l y for A m e r i c a n eel

e l ve rs in the lower r eaches of the Bay of Fundy in Nova Sco t ia and N e w Brunswick . As of

1 9 9 6 , a to ta l of n ine l i censes have been i ssued , cove r ing all of the Sco t i a -Fundy a rea

c o a s t l i n e excep t sec t ions of s o u t h w e s t e r n Nova Scot ia , the nor th shore of M inas Bas in in

t h e U p p e r Bay of Fundy, a n d the sou thwes t po r t ion of C a p e Bre ton Is land (F igure 1).

T h e l i censes i ssued a n d ter r i tor ies f ished can be conven ien t l y g rouped into seven

g e o g r a p h i c a reas : 1) t he lower Bay of Fundy, N.B. ( L B F N B ) , ex tend ing f rom the Ma ine

b o r d e r to the Saint J o h n River ; 2) Ch ignec to Bay ( C H I G N E C T O ) , ex tend ing f rom the

Sa in t J o h n River t h rough C h i g n e c t o Bay to C a p e C h i g n e c t o ; 3) M inas Bas in ( M I N A S ) ,

f r o m C a p e C h i g n e c t o t h r o u g h M inas Bas in to, a n d inc lud ing , K ings County, N.S. ; 4) lower

Bay of Fundy , N.S. ( L B F N S ) , c o m p r i s i n g Annapo l is and D igby Coun t ies , N.S. ; 5) Sou th

S h o r e , N.S. ( S S N S ) , ex tend ing f rom Queens County , N.S. to Hal i fax Harbour ; 6) Eas te rn

S h o r e , N.S. ( E S N S ) , cove r ing no r th of Halifax Harbour to the C a n s o C a u s e w a y ; 7)

E a s t e r n C a p e Breton ( E C B ) , compr i s i ng the At lant ic coas t of C a p e Breton f rom the

C a n s o C a u s e w a y to C a p e N o r t h , wh i ch can p resen t l y be ignored because no e lvers have

ye t b e e n c a u g h t there.

Bull. Fr. Pêche Piscic. (1998) m : 103-116 - 1 0 5 -

N E W B R U N S W I C K

P R I N C E E D W A R D . I S L A N D

APRIL MAY JUNE

M A I N E

ATLANTIC OCEAN

Figure 1 Map of the Maritime Provinces with boundaries and extent (indicated by thickened coastline) of the geographic areas where fisheries occur for American eel elvers, 1996 (LBFNB - lower Bay of Fundy, N.B. ; CHIGNECTO - upper Bay of Fundy, N.B. and Chignecto Bay ; LBFNS - lower Bay of Fundy, N.S. ; SSNS -southern Atlantic coast of N.S. ; ESNS - eastern Atlantic coast of N.S. ; ECB -eastern Cape Breton Island). The pie charts indicate the weighted mean monthly percentages of total catch (kg) of American eel elvers, by geographic area, for the years 1994 to 1996 (except CHIGNECTO and ESNS areas which have data only for 1995 and 1996).

Figure 1 Carte des Provinces Maritimes illustrant les limites et l'étendue (épaisseur du trait de ligne de côte) des régions géographiques où a été pratiquée la pêche de la civelle en 1996 (LBFNB = partie néo-brunswickoise de l'entrée de la baie de Fundy) ; CHIGNECTO = partie néo-brunswickoise du fond de la baie de Fundy et baie de Chignecto ; LBFNS = partie néo-écossaise du fond de la baie de Fundy ; SSNS = côte atlantique sud de la Nouvelle-Ecosse ; ESNS = côte atlantique est de la Nouvelle-Ecosse ; ECB = est de l'île du Cap-Breton). Le diagramme circulaire indique les pourcentages mensuels moyens pondérés des prises totales (kg) de civelles, par région géographique, de 1994 à 1996 (sauf en ce qui concerne les régions de CHIGNECTO et de l'ESNS, pour lesquelles les données se limitent à 1995 et 1996).


Expe r imen ta l l i censes are i ssued for a speci f ic pu rpose , have no guaran tee of

r e n e w a l , a n d may conta in a var ie ty of restr ict ions. Present restr ict ions for each l icense

i nc l ude : 1) a de f ined geograph ic a r e a with approva l to f ish only speci f ic r ivers ( f rom 5-18

in n u m b e r ) in that a rea ; 2) no elver f ishery in rivers in wh ich an exist ing f ishery occurs for

la rger ee ls ; 3) l imits on the type of f ishing gea r permi t ted (genera l ly dip net but inc lud ing

v a r i o u s t y p e s of t rap, fyke, and push nets) and quant i ty of gear, o ther than dip net ;

4) a r equ i remen t for live re lease of bycatch of other spec ies ; 5) an overal l quo ta of,

usual ly , o n e tonne , w i th a l imit of 3 0 0 kg on the quant i ty f rom any s ing le river (annual quota

e x t e n s i o n s of up to 300 kg m a y be gran ted in years in wh ich the quota is quick ly reached) ;

6) p e r m i s s i o n for t he sa le of e lvers (f ishery regulat ions o therw ise prohibi t catch and

re ten t ion of ee ls less t han 2 0 c m long) except for th ree l i censes whe re ca tch is restr ic ted

to a q u a c u l t u r e use ; 7) a requ i remen t to submi t , mon th l y du r ing the f ish ing season , a

r e c o r d of dai ly ca tch (kg) for each river ( f ishing effort (h), by gear type, is a lso requi red as

of 1 9 9 6 ) . In 1997, four expe r imen ta l elver f ishing l icenses we re conver ted to regular

l i censes w i th the ob jec t ive of p rov id ing the mo re es tab l i shed f ishers wi th s o m e assurance

of con t i nu i t y to the f ishery, a n d an indust ry - funded, i ndependen t quo ta moni tor ing sys tem

w a s i m p l e m e n t e d . O n c e i ssued , a regular l icense is annua l ly renewab le upon appl icat ion

a n d is res t r i c ted on ly by the prov is ions a l lowed under the C a n a d a F ishery Genera l

R e g u l a t i o n s a n d Mar i t ime Prov inces Fishery Regu la t ions govern ing such top ics as f ishing

s e a s o n s , locat ions, quo tas , gea r t ypes and usage , bycatch prov is ions and ca tch and effort

r epo r t i ng . Eligibi l i ty cr i ter ia for n e w l icenses t o f ish present ly una l loca ted terr i tor ies have

b e e n d e v e l o p e d wh i ch a c c o m m o d a t e native f isher ies a n d needs of the aquacu l tu re

indust ry .

T h e res t r ic ted issue of elver f i sh ing l icenses a n d the large geograph ic area covered

by e a c h l i cense , coup led w i th the provisions of the C a n a d i a n Pr ivacy Act and Access to

I n f o rma t i on Ac t , prevent publ ic presentat ion of the deta i led geograph ic ana lys is of elver

c a t c h e s b e c a u s e of t h e poss ib le l inkage of speci f ic catch va lues to an indiv idual f isher

t h e r e b y revea l ing pe rsona l e c o n o m i c in format ion. S u b s e q u e n t d i scuss ions of the f ishery

wi l l be cons t ra ined by th is fact but th is analys is is ful ly cons is ten t wi th a deta i led ana lys is

of t h e f i she ry ca tch a n d effort da ta .

C O M M E R C I A L F ISHERY

T h e e lver f ishery in the Scot ia -Fundy a r e a is pr imar i ly a d ip-net f ishery, a l though

S h e l d o n e lver t raps ( S H E L D O N , 1974) , fyke nets, pots , and a push net are a lso used

d e p e n d i n g u p o n the g é o m o r p h o l o g i e a n d d ischarge cond i t ions wi th in the t idal a n d near

head -o f - t i de f ish ing z o n e s of each r iver mouth . Elver ca tches inc reased s lowly f rom 26 kg

to 2 2 7 kg be tween 1989 a n d 1992 then approx imate ly doub led annua l ly until 1995, w h e n

t h e ca t ch to ta l l ed 3 2 3 8 kg , t hen dec l ined about 1 2 % to 2 8 6 2 kg in 1996 (Table I). T h e

recen t l y h i gh , but annua l l y a n d seasona l l y volat i le, pr ice of e lvers (mean of about $ 540

C a n a d i a n per kg in 1996) va lued the 1996 f ishery at 1.5 mi l l ion dol lars. In the early years,

t h e low c a t c h e s der ive f r om just t w o or three f i shers w h o w e r e deve lop ing their know ledge

of t h e e l ve r runs to va r ious r ivers in their l icense area, their ski l ls in ca tch ing , hand l ing , and

sh i pp i ng e lvers , and es tab l i sh ing marke ts for their ca tch . A s f isher ski l ls a n d knowledge

i m p r o v e d a n d elver f i shery l i censes for new geograph ic a reas w e r e g ran ted , the total catch

i n c r e a s e d . T h e f ishery is ma tu r ing in the sense that no addi t iona l l i censes wil l be issued for

t he f o reseeab le future, the p resen t exper imenta l f ish ing pe rm i t s are be ing conver ted to

regu la r l i censes , and the f i shers have acquired substant ia l f i sh ing and marke t ing ski l ls.

E lver f ishers fo l lowed a s imi lar approach in all a reas. Dur ing the ear ly part of the

f i sh ing s e a s o n , r ivers pe rm i t t ed to be f ished w e r e checked per iod ica l ly for e lvers. W h e n

the i r p r e s e n c e was c o n f i r m e d , mo re regular f ishing b e g a n . F ish ing typical ly occur red

n ight ly d u r i n g the e lver run , wi th f ish ing intensity usual ly d e p e n d e n t upon elver density.

H e a v y rainfal l , co ld w e a t h e r per iods , and unfavorable (dec l in ing or low) even ing t ides of ten

Bull. Fr. Pêche Piscic. (1998)349 :103-116 — 107 —

Tab le I

A n n u a l c a t c h ( k g ) o f A m e r i c a n ee l e l v e r s i n t h e S c o t i a - F u n d y a r e a , b y p r o v i n c e ,

a n d n u m b e r o f l i c e n s e s i s s u e d f r o m 1 9 8 9 t o 1996 .

T a b l e a u I

P r i s e s a n n u e l l e s ( k g ) d e c i v e l l e s d a n s le s e c t e u r d e S c o t i a - F u n d y , pa r p r o v i n c e ,

et n o m b r e d e p e r m i s d é l i v r é s d e 1989 à 1996 .

New Nova Total Number of Year Brunswick Scotia catch licenses

1989 0 26 26 2 1990 132 42 174 2 1991 65 0 65 2 1992 227 0 227 3 1993 534 179 713 3 1994 650 924 1 574 4 1995 549 2 689 3 238 7 1996 449 2 413 2 862 9

c a u s e d t empo ra ry cessa t i on of f i sh ing . F ish ing c e a s e d w h e n the f ishers j u d g e d the catch-

per -hour uneconomic . Near m a x i m a l e c o n o m i c f i sh ing p ressu re may be app l ied in most

f ish ing terr i tor ies b e c a u s e the h igh va lue of e lvers p rov ides incent ive to ach ieve quotas

even at relat ively low ca t ch rates. Consequent ly , t he recent pa t te rns in annua l a n d

geograph ic ca tch var iabi l i ty may ref lect under ly ing b io log ica l p h e n o m e n a .

C A T C H V A R I A B I L I T Y

Elver ca tches va ry annua l l y and seasona l l y w i th in a n d a m o n g the six geograph ic

reg ions whe re f i sh ing p resen t l y occurs . B e t w e e n 1994 a n d 1996 ( the years wi th the

h ighest annua l ca t ches and a ma tu r ing f ishery in mos t a reas ) , ca t ches var ied among

reg ions up to abou t e ight - fo ld . C a t c h e s w e r e cons is ten t ly h ighes t a l ong the S o u t h Shore

and lower Bay of Fundy, N.S., modera te l y h igh in the lower Bay of Fundy, N.B., lower a long

the Eas tern Shore , N.S., a n d lowest (and s imi lar ) in the u p p e r Bay of Fundy areas of

Ch ignec to Bay and M inas Bas in (F igure 1).

Wi th in a geograph ic reg ion , the elver ca tch d e p e n d s on elver a b u n d a n c e , f ishing

ef fort , and elver ca tchab i l i t y (avai labi l i ty, f i sh ing e f f i c iency) a n d the d ist r ibut ion of

e lvers th rough the run . F ish ing effort (all gear t ypes ) in 1996 var ied a m o n g reg ions f rom

abou t 4 3 0 hrs to a lmos t 8 900 hrs (mode 1 100 hrs) d is t r ibu ted t h roughou t the elver run

roughly in p ropor t ion to perce ived elver a b u n d a n c e by the f isher. S ince catch ef f ic iencies

vary a m o n g gear t ypes a n d the mix of gear t ypes var ies a m o n g reg ions , fur ther analys is

wil l dea l on ly wi th the mos t w ide ly used gear, the d ip net, w h i c h w a s respons ib le for 6 6 % of

the to ta l 1996 ca t ch . D ip-net f i sh ing ef f ic iency has been a s s u m e d to be cons tan t among

f ishers and s i tes, wh i ch a re sma l l - t o -med ium s ized r ivers. M o d e r a t e f ish ing effort, resul t ing

in little or no c a t c h , w a s e x p e n d e d in all a reas check ing for t he s tar t a n d possib le late

cont inuat ion of the e lver runs to indiv idual r ivers, but o n c e e lvers w e r e present , f ishing

effort wi th in an ind iv idua l r iver or geog raph i c reg ion t e n d e d to va r y w i th f ish ing success .

Consequent ly , dai ly (more accurate ly , n ight ly) ca tch (kg) , f i sh ing ef for t (h) , and catch-per-

uni t - f ish ing effort ( C P U E ; kg h ' ) d is t r ibut ions for e a c h river, a g g r e g a t e d by f i shery a rea ,

Bull. Fr. Pêche Piscic. (1998) 349 :103-116 — 108 —

F i g u r e 2 B o x p l o t s o f A m e r i c a n e e l e l v e r da i ly c a t c h ( k g ) , d i p n e t f i s h i n g e f f o r t (h ) , a n d c a t c h p e r u n i t e f f o r t ( C P U E ; k g h 1 ) by g e o g r a p h i c r e g i o n ( L B F N B - l o w e r B a y of F u n d y , N . B . ; C H I G N E C T O - u p p e r B a y of F u n d y , N .B . a n d C h i g n e c t o B a y ; L B F N S - l o w e r B a y o f F u n d y , N.S. ; S S N S - s o u t h e r n A t l a n t i c c o a s t o f N.S. ; E S N S - e a s t e r n A t l a n t i c c o a s t o f N.S.) in t h e S c o t i a - F u n d y a r e a o f A t l a n t i c C a n a d a , 1996. T h e b o x c o n t a i n s t h e c e n t r a l 5 0 % o f v a l u e s , t h e m e d i a n is t h e c e n t r a l l i n e w i t h i n t h e b o x , a n d x- a n d o - v a l u e s r e p r e s e n t o u t l i e r s a n d fa r o u t l i e r s .

F i g u r e 2 T r a c é s e n b o î t e s d e s p r i s e s q u o t i d i e n n e s d e c i v e l l e s ( k g ) , d e l ' e f f o r t d e p ê c h e à l ' é p u i s e t t e (h) et d e s p r i s e s p a r u n i t é d ' e f f o r t ( P U E , k g h 1 ) , p a r r é g i o n g é o g r a p h i q u e ( L B F N B = p a r t i e n é o - b r u n s w i c k o i s e d e l ' e n t r é e d e la b a i e d e F u n d y ; C H I G N E C T O = p a r t i e n é o - b r u n s w i c k o i s e d u f o n d d e la b a i e d e F u n d y et b a i e d e C h i g n e c t o ; L B F N S = p a r t i e n é o - é c o s s a i s e d u f o n d d e la b a i e d e F u n d y ; S S N S = c ô t e a t l a n t i q u e s u d d e la N o u v e l l e - E c o s s e ; E S N S = c ô t e a t l a n t i q u e e s t d e la N o u v e l l e - E c o s s e ) d a n s le s e c t e u r d e S c o t i a - F u n d y d u C a n a d a a t l a n t i q u e e n 1 9 9 6 . L a b o î t e c o n t i e n t le 5 0 % c e n t r a l d e s v a l e u r s , la m é d i a n e e s t la l i g n e c e n t r a l e à l ' i n t é r i e u r d e la b o î t e , et l e s v a l e u r s x et o r e p r é s e n t e n t l e s c a s a b e r r a n t s e t e x t r ê m e m e n t a b e r r a n t s .

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Bull. Fr. Pêche Pisclc. (1998) 349:103-116 — 109 —

w e r e highly r ight s k e w e d a n d leptokur t ic (F igure 2 ) . T h e f i shery stat is t ics (catch, effort,

C P U E ) , wh ich inc lude days of zero ca tch , are repor ted under the cond i t i ons of the f ishing

l icense and are be l ieved accu ra te b e c a u s e of the h igh e c o n o m i c va lue of e a c h l icense, the

l imi ted n u m b e r of l i censes , the act ive coopera t ion of f i shers , a n d the s ta ted low to lerance

by f ishery m a n a g e r s to se r i ous l icense inf ract ions. Ca t ch s tat is t ics a re inherent ly var iable

due to the var iabi l i ty in e lver catchabi l i ty and a b u n d a n c e ( C A S T E L N A U D et al., 1994) .

Dip-net f i sh ing effort va r ied a m o n g f ive geograph ic reg ions f rom abou t 3 0 0 h to over

1 700 h (M inas Bas in w a s exc luded because d ip-net ca t ches we re inseparab le f rom

ca tches by o ther gea r t ypes ) . T h e elver ca tch by d ip net to ta l led 1 903 kg in 5 2 0 4 h of

f ish ing effort in t hese f ive geograph ic reg ions. A l t hough da i ly e lver ca tch (kg) by d ip net

w a s s igni f icant ly co r re la ted wi th f ish ing effort (h) a m o n g the f ive reg ions ( r b o o l r anged from

0.45 to 0 .62, N r anged f r om 8 9 to 306 , P = 0 .0002 ; B = 5 0 0 0 rep l ica tes) , t he coef f ic ients

of de te rm ina t ion (r 2 ) of the re la t ions ranged f r om 0.21 to 0 .38 , imp ly ing that ca tch w a s not

so le ly d e p e n d e n t on f i sh ing effort. Randomiza t i on tes ts w e r e used in all ana l yses because

of the p resence of o n e or m o r e of the fo l lowing cond i t i ons : sma l l or d i f fer ing s a m p l e sizes,

unknown or h ighly r ight s k e w e d a n d leptokur t ic stat is t ical d is t r ibu t ions of var iab les , and

s igni f icant ( P < 0 .0002) he te rogene i t y in reg iona l C P U E va r i ances ( E D G I N G T O N , 1987) .

T h e use of C P U E as an index of a b u n d a n c e (dens i ty ) requ i res that ca tch rates be

propor t iona l to f ish a b u n d a n c e . A l t hough the re lat ion b e t w e e n f ish a b u n d a n c e and C P U E

is b iased w h e n f ish m ig ra te t h rough a local f i sh ing z o n e b e c a u s e the rat io of C P U E to

a b u n d a n c e d e p e n d s on the dura t ion of f i sh ing a n d C P U E var ies t h rough t h e run

( S A M P S O N , 1991) , s u c h b ias may be minor for th is e lver f i shery b e c a u s e f ishing activity

occurs essent ia l l y t h r o u g h o u t the e lver run, a n d the ca t ch a n d seasona l pa t te rn of the

f ishery ref lect t he a b u n d a n c e and pat te rn of the e lver run . E lvers s p e n d a relat ively short

t ime t ransi t ing the f i sh ing zone o n c e hydro log ica l cond i t i ons (r iver water t empera tu re and

level) reach levels c o n d u c i v e to u p s t r e a m m o v e m e n t ( C A N T R E L L E , 1981) . Thus , the

pat tern of ca tch in the e lver f ishery w a s s imi lar to, but l a g g e d f r o m , that by I r ish- type elver

t raps (O 'LEARY, 1971) l oca ted at t he head of t ide in the East River, Chester , ( lag 1-3 d)

loca ted abou t m i d w a y a long the Sou th Sho re (F igure 1) a n d the Eas t River, Sheet

Harbour, ( lag 8-9 d) abou t m idway a long the Eas te rn S h o r e a n d abou t 140 km distant

(JESSOP, 1997 ; unpub l i shed da ta ) . A l though the e lver ca t ch in the East River, Chester ,

w a s 1.3 t imes that in the East River, Shee t Harbour , the C P U E var ied wi th elver run size ;

the elver run w a s 3.3 t imes larger a n d the C P U E of the f i shery w a s 3.4 t imes larger for t he

East River, Chester , t han for the East River, S h e e t Harbour . By geog raph i c a rea , the total

e lver ca tch w a s 3.3 t imes larger a n d C P U E w a s 3.4 t i m e s larger for the f ishery on the

Sou th Sho re , w h e r e the East River, Ches te r is loca ted , t h a n on the Eas te rn Sho re where

the East River, Shee t Ha rbou r is loca ted . T h e pos i t ive cor re la t ions , for e a c h of the f ive

geograph ic reg ions, b e t w e e n C P U E and ca tch ( r ^ , f r om 0.67 to 0 .93 , /V f rom 8 9 to 306, all

P < 0 .0002 ; all B = 5 000 ) ind icate that ca tch inc reases w i th inc reas ing elver abundance

(densi ty) in e a c h f ishery. T h u s , because the seasona l pa t te rn a n d ca tch of the e lver f ishery

mi r rored the pa t te rn and a b u n d a n c e of the e lver run to t w o r ivers in di f ferent geograph ic

reg ions and C P U E a n d ca t ch we re cor re la ted in all reg ions , it is p laus ib le that t h e e lver

f ishery ref lects e lver a b u n d a n c e wi th in the rema in ing e lver f i she ry reg ions.

M e a n da i l y C P U E v a l u e s d i f fe red s i gn i f i can t l y a m o n g r e g i o n s (Table II ;

randomiza t ion A N O V A , P = 0 .0002 , df = 4 1193 ; B = 5 0 0 0 ) . Pa i red c o m p a r i s o n s of mean

( 9 5 % CI ; B = 1 000 ) d ip -net C P U E di f fered s ign i f icant ly ( P = 0 .0002 ; B = 5 000) be tween

all but t w o of ten poss ib le c o m p a r i s o n s ( L B F N B : L B F N S , P = 0.49 ; C H I G N E C T O :

E S N S , P = 0 .45) . T h e cr i t ica l va lue used for Bonfer ron i ad j us tmen t of mul t ip le pa i rwise

c o m p a r i s o n s w a s 0 .005 . T h e subs tan t ia l f i sh ing effort in al l reg ions, low corre lat ion

be tween ca t ch a n d f i sh ing effort, cor re la t ion be tween C P U E a n d ca tch , a n d s igni f icant

d i f fe rences in C P U E a m o n g reg ions suppor t a conc lus ion of reg iona l d i f ferences in e lver

abundance .


T a b l e II

M e a n d a i l y c a t c h p e r u n i t o f f i s h i n g e f f o r t ( C P U E ) , w i t h 9 5 % c o n f i d e n c e i n t e r v a l s

(C I ) , b y g e o g r a p h i c r e g i o n f o r t h e c o m m e r c i a l e l v e r d i p - n e t f i s h e r y i n t h e S c o t i a -

F u n d y a r e a of A t l a n t i c C a n a d a , 1996.

T a b l e a u II P r i s e s m o y e n n e s q u o t i d i e n n e s p a r u n i t é d ' e f f o r t d e p ê c h e ( P U E ) , pa r r é g i o n g é o g r a p h i q u e , d e la p ê c h e c o m m e r c i a l e d e la c i v e l l e à l ' é p u i s e t t e d a n s le s e c t e u r d e S c o t i a - F u n d y d u C a n a d a a t l a n t i q u e e n 1996 ( i n t e r v a l l e s d e c o n f i a n c e d e 9 5 % ) .

Region CPUE 95% CI Lower Bay of Fundy, N.B. (LBFNB) 0.63 0.48-•0.79 Chignecto (CHIGNECTO) 0.07 0.05-•0.09 Lower Bay of Fundy, N.S. (LBFNS) 0.70 0.58-•0.85 South Shore, N.S. (SSNS) 0.27 0.23-•0.31 Eastern Shore, N.S. (ESNS) 0.08 0.06-•0.10

T h e cons is ten t reg iona l var iabi l i ty in annua l elver ca tches wi th in the Sco t ia -Fundy

a r e a ind i ca tes reg ional d i f fe rences in the coasta l d is t r ibut ion of e lvers . D E K K E R (1986)

r e p o r t e d var ia t ion in g lass eel ca t ches within the relat ively smal l geograph ic area of

H o l l a n d , C A S T E L N A U D et al. ( 1994) documen ted the geograph ic var iabi l i ty in elver ca tch

a l o n g the At lan t ic coas t of France, wh i le M O R I A R T Y (1990) f ound substant ia l d i f ferences

in a n n u a l e lver ca tch t h rough w e s t e r n a n d nor thern Europe as wel l as long- te rm c h a n g e s

in e lver ca t ch over a w i d e geog raph i c area. T h e geograph ic d is t r ibut ion of e lvers in the

S c o t i a - F u n d y a rea is genera l l y re f lec ted in t h e f ishery for larger ee ls , w h e r e the largest

f i she r i es occu r in the Sa in t J o h n River of sou thwest New Brunswick a n d a long the

s o u t h e r n A t lan t i c coas t of Nova Sco t ia and smal le r f isher ies occur in the Ch ignec to Bay

a n d M i n a s Bas in a reas of the uppe r Bay of Fundy and a long the Eas te rn Shore of Nova

S c o t i a ( J E S S O P , 1982 ; 1996b) .

T h e hypo thes is that e lver run s ize is propor t ional to river s ize (dra inage area,

d i s c h a r g e ) w i th in the Sco t i a -Fundy a r e a was examined by cor re la t ion b e t w e e n the m e a n

da i ly d ip -ne t C P U E a n d river d ra inage area for those r ivers (at least two r ivers are

r e p r e s e n t e d f r o m e a c h reg ion) w h e r e the total ca tch was by d ip-net and f ish ing effort

o c c u r r e d o n at least 20 days ( m e a n = 39 d , range = 22 -67 d ) . T h e lack of s igni f icant

pos i t i ve cor re la t ion ( rboot = 0 .50, N = 19, P = 0 . 5 1 , one -s ided test ; B = 5 000) may be

e x p l a i n e d by the obscu r ing effect of differing e lver abundance a m o n g geograph ic regions

a n d t h e poss ib i l i ty that e lver ca tchab i l i t y by dip-net may d e c r e a s e w i th inc reas ing river s ize

(d ra inage a r e a med ian = 149 k m 2 , range 8-1 833 km 2 ) . Add i t iona l ev idence against the

hypo thes i s tha t e lver run s ize is p ropor t iona l to river s ize and for a geograph ic d i f ference in

e lver a b u n d a n c e is p rov ided by the 1996 est imate of a run of 1 124 000 (± 50 000 ;

9 5 % CI ) e lvers , es t ima ted f r om e lver t rap and commerc ia l f i shery ca tches , a n d densi ty of

8 4 0 0 e l v e r s k m 2 to the East River, C h e s t e r (dra inage a rea of 134 km 2 ) on the Sou th Shore

of N o v a Sco t ia and of 337 000 (± 14 000 ; 9 5 % CI) e lvers and dens i ty of 640 e lvers k m 2 to

t h e Eas t River, Shee t Ha rbou r (d ra inage area of 526 km 2 ) on the Eas tern Shore of N.S.,

( J E S S O P , 1997) . Wi th in a reg ion of s imi lar coas ta l densi ty of e lvers, the e lver run to a

r iver m a y be p ropor t iona l to its s ize but that hypothesis has not yet been tes ted .

C o m m e r c i a l quant i t ies of e lvers first arrive in es tuar ine wa te rs in late Apr i l or ear ly

May, d e p e n d i n g upon the a rea , p e a k in May ( 5 7 - 8 9 % of ca tch) , a n d usual ly dec l ine to low

a b u n d a n c e in, or before, ea r l y - to -m id J u n e (Figure 1). Sma l l quant i t ies of e lvers ( less than

1 % of to ta l ca tch ) may con t i nue to en te r s t reams a long the At lant ic coas t and in the upper


Bay of Fundy in ear ly Ju ly a n d may con t inue into Augus t in s o m e At lant ic c o a s t rivers

( J E S S O R unpub l i shed da ta ) . For the years 1994 to 1996 , the p ropor t ion of the regional

elver ca tch occu r r i ng in Apr i l i nc reased f rom zero a l ong t h e Eas te rn S h o r e of N o v a Scotia

to 2 9 % ( range 1 7 % - 4 3 % ) a long the Sou th S h o r e t hen cons is ten t l y dec l i ned a long a route

p r o g r e s s i n g in to t h e l ower Bay of Fundy , N .S . ( 2 5 % ; r a n g e 9 % - 3 5 % ) a n d

coun te r -c lockw ise t h rough the upper Bay of Fundy f r o m Nova Sco t ia ( 9 % ; range 0 % - 1 7 % )

to N e w Brunsw ick ( 8 % ; range 6 % - 1 1 % ) a n d towards the lower Bay of Fundy, N.B. ( 2 % ;

range 0 . 1 % - 4 % ) . Dur ing May, the p ropor t ion of reg iona l e lver ca tch inc reased t o 6 7 %

( range 6 4 % - 6 8 % ) a long the Eastern Shore , N.S., to 5 7 % ( range 4 6 % - 7 9 % ) a n d 6 2 % (range

3 3 % - 7 0 % ) a long the Sou th Shore and lower Bay of Fundy, N.S., to 8 0 % (range

7 1 % - 9 0 % ) in M inas Bas in a n d 8 3 % ( range 8 0 % - 8 9 % ) in C h i g n e c t o Bay, a n d 8 9 % (range

8 8 % - 9 2 % ) in the lower Bay of Fundy, N.B. J u n e ca t ches dec l i ned in a s imi lar pa t te rn f rom

3 3 % ( range 3 1 % - 3 6 % ) a long the Eas tern Sho re to 9 % ( range 8 % - 1 0 % ) in the lower Bay of

Fundy, N.B.

O C E A N O G R A P H I C E F F E C T S O N E L V E R D I S T R I B U T I O N

A l though su rveys have es tab l i shed the p r e s e n c e of la rvae of t he A m e r i c a n ee l in the

Gulf S t r eam o f fshore of Nova Scot ia ( T E S C H , 1977 ; M C C L E A V E , 1993) , no surveys

have e x a m i n e d the d is t r ibu t ion or surv iva l of la rvae /g lass ee ls on the cont inenta l shel f as

they t ransi t th is reg ion before en ter ing coasta l wa te rs . Annual ly , var iab le b io logical

(ocean ic food supply, p rédat ion) and océanog raph ie (ocean ic and coasta l water cur ren ts

and tempera tu res ) cond i t i ons may govern larval ocean i c surv iva l a n d d is t r ibu t ion on a

cont inenta l a n d reg iona l sca le ( M C C L E A V E , 1993) . T h u s , the Gul f S t r e a m advec ts

A m e r i c a n eel l ep tocepha l i nor th a n d east f r om thei r ha tch ing a rea in the S a r g a s s o Sea to

a reas off the At lant ic coas t of Nor th A m e r i c a ; speci f ical ly , off the coast of the Mar i t ime

Prov inces. A m e r i c a n eel e lvers a re hypo thes ized ( K L E C K N E R a n d M C C L E A V E , 1985 ;

M C C L E A V E , 1987) to det ra in act ively f rom the Gul f S t r e a m a ided by the océanograph ie

p rocesses of d i f fus ion a n d the in t rus ion of edd ies and w a r m - c o r e r ings of Gulf S t ream

water into the s lope wa te r off the cont inenta l shelf. T h e s e m e a n d e r s and loops inc rease

the pa th length and reduce net cur rent s p e e d of t he Gul f S t r e a m off the New Eng land -

Mar i t ime Prov inces coas t and may a l low e lvers to m o r e act ive ly m o v e into s lope waters

before be ing ca r r i ed fu r ther nor theas t . Lep tocepha l i that a re on togenet ica l l y r e a d y then

m e t a m o r p h o s e into g lass e lvers, pe rhaps w h e n the s e a b o t t o m over the sha l low

cont inenta l shel f is e n c o u n t e r e d , c h a n g e the i r behav iou r f r om a diel vert ical r hy thm to a

t idal rhy thm, a n d m o v e s h o r e w a r d via se lec t ive t idal s t r e a m t ranspor t in a p rocess similar

to that used in es tua r ine wa te rs ( M C C L E A V E a n d K L E C K N E R , 1982) . T h e relative

cont r ibut ion to s h o r e w a r d m o v e m e n t p layed by ac t ive s w i m m i n g is uncer ta in a n d the

ave rage s w i m m i n g s p e e d is u n k n o w n . T h e nega t i ve buoyancy of g lass ee ls may assist in

tak ing a d v a n t a g e of sho reward mov ing bo t tom cur ren ts but requ i res s w i m m i n g act ivi ty for

dep th m a i n t e n a n c e ( H I C K M A N , 1981) .

Off Nova Sco t ia , Gul f S t r eam sur face cu r ren ts f low abou t 85 k m d " 1 to t h e east-

nor theas t ( W O R T H I N G T O N , 1976) , w i th the no r the rn e d g e of the Gul f S t r eam about

490 k m ( range 3 5 0 - 6 2 0 km) o f fshore at the sou the rn e n d of Nova Scot ia and 6 2 5 k m

( range 3 7 5 - 7 7 5 km) o f fshore at the no r the rn e n d ( D R I N K W A T E R et al., 1994 ; F igure 3 ) .

The she l f -s lope f ront ( the nar row b o u n d a r y separa t i ng the coo l shel f wa te rs f r o m the

w a r m e r s lope wa te rs o f fshore of t he cont inenta l she l f ) is abou t 100 k m c loser to the

sou thwes t coas t (Sou th Shore ) than to the no r theas t coas t (Eas te rn Shore ) o f Nova

Scot ia . Off the sou the rn t ip of Nova Scot ia , the con t i nen ta l shel f (Scot ian Shel f ) is about

130 k m w ide , i nc reas ing to 2 4 0 k m w ide off C a p e B r e t o n , w i th d e p t h s averag ing less than

200 m a n d less t han 100 m over many banks . T h e pos i t ions of t he Gulf S t r eam,

she l f /s lope f ront , a n d Sco t ian Shel f make it po tent ia l ly eas ie r for e lvers to c o m e inshore

a long the sou thwes t rather than a long the no r theas t coas t , a s s u m i n g that océanograph ie

cond i t ions a re equa l t h roughou t the area.


68° 64° 60° 56° 52° 48°

F i g u r e 3

M a p o f A t l a n t i c C a n a d a s h o w i n g t h e m a j o r o c é a n o g r a p h i e s u r f a c e c u r r e n t s a n d

b o t t o m f e a t u r e s w i t h i n t h e c o n t i n e n t a l she l f . T h e t h i c k n e s s o f l i n e s i n d i c a t i n g

t h e c u r r e n t s is p r o p o r t i o n a l t o c u r r e n t s t r e n g t h .

F i g u r e 3

C a r t e d u C a n a d a a t l a n t i q u e i l l u s t r a n t l e s g r a n d s c o u r a n t s o c é a n o g r a p h i q u e s d e s u r f a c e e t l e s c a r a c t é r i s t i q u e s d u f o n d s u r le p l a t e a u c o n t i n e n t a l . L ' é p a i s s e u r d e s l i g n e s r e p r é s e n t a n t l e s c o u r a n t s e s t p r o p o r t i o n n e l l e à la f o r c e d e c e s d e r n i e r s .

However , océanog raph ie cond i t ions b e t w e e n the Gul f S t r eam and the coas t are

c o m p l e x , w i t h impo r t an t s e a s o n a l c h a n g e s in sal ini ty, t e m p e r a t u r e , a n d cu r ren ts ,

pa r t i cu la r l y over the Sco t ia Shel f and in the Gul f of Maine and Bay of Fundy ( H A C H E Y et

al., 1 9 5 4 ; S U T C L I F F E et a/., 1976 ; DR INKWATER et al., 1979, 1994 ; S M I T H 1983,

1989 ) . T h e reg ion f r o m the Gulf of St. Lawrence to the Gul f of Ma ine inc lus ive may be

c o n s i d e r e d as an océanog raph ie s y s t e m in w h i c h s o m e events occur r ing as far sou th as

t h e Gul f of M a i n e are l inked to annua l f reshwater d ischarge f rom the Gul f of St. Lawrence

( S U T C L I F F E et al., 1976 ; D R I N K W A T E R et al., 1979 ; S M I T H , 1989) . T h e waters of the

S c o t i a n She l f a re a m ix tu re of low sal ini ty wa te r f rom the Gulf of St. Lawrence (via the

N o v a Sco t i a Cur ren t ) a n d s lope water, which is in turn a mix ture of wa te rs f r om the w a r m

Gul f S t r e a m , the North Cent ra l At lant ic , and t h e co ld Labrador Cur rent (HACHEY, 1954) .

G i v e n the k n o w n a n d hypothes ized ef fects of ocean ic cond i t ions on larval eel

t r a n s p o r t a n d surv iva l ( M C C L E A V E , 1987 , 1993 ; C A S T O N G U A Y et al., 1994) and of t idal

c o n d i t i o n s in e s t u a r i e s ( M C C L E A V E and K L E C K N E R , 1982 ) , it is p laus ib le that

o c é a n o g r a p h i e fea tures cou ld con t r ibu te to t h e greater obse rved elver a b u n d a n c e in the

S o u t h S h o r e and lower Bay of Fundy a reas of Nova Scot ia than in the Eastern

S h o r e a rea of Nova Sco t ia . Firstly, wa rm-co re eddy act iv i ty by the Gul f S t r eam is more


act ive sou thwes t of (wes t of abou t 63° W ; D R I N K W A T E R et al., 1996 ) t h a n nor theas t of

Hal i fax, wh ich is rough ly m i d w a y a long t h e At lant ic coas t of N o v a Sco t i a . W a r m - c o r e

edd ies t end to m o v e s o u t h w e s t wh i le e m b e d d e d in the s l o p e water , wh i ch moves

no r theas t at a b o u t 4 k m d 1 ( S M I T H a n d P E T R I E , 1 9 8 2 ) . Second l y , af ter t rans i t ing t h e shelf

e d g e to the Sco t i an Shel f , e lvers in near -su r face w a t e r s w o u l d e n c o u n t e r the of fshore

b ranch of the Nova Sco t i a Cu r ren t wh i ch m o v e s s o u t h w e s t at less t h a n 1 km-d" 1 . However ,

e lvers rema in ing near b o t t o m over the Sco t i an She l f ( a c c o r d i n g to t h e behav ioura l

hypo thes is p r o p o s e d by K L E C K N E R a n d M C C L E A V E (1985 ) a n d M C C L E A V E (1987))

cou ld ut i l ize a d e e p s h o r e w a r d cu r ren t of abou t 2 km-d ' a s s o c i a t e d w i th a su r face of fshore

drift ( L A U Z I E R , 1967) to m o v e t o w a r d s the coast . Inshore cu r ren t m o v e m e n t is par t icu lar ly

s t rong in the d e e p e r c h a n n e l wa te rs b e t w e e n t h e E m e r a l d a n d L a H a v e B a n k s sou th of

Hal i fax and t h rough t h e N o r t h e a s t C h a n n e l b e t w e e n t h e S c o t i a n She l f a n d G e o r g e s Bank

( S M I T H a n d P E T R I E , 1 9 8 2 ; S M I T H , 1989) a l t h o u g h in f low of s l ope wa te r t h r o u g h the

Nor theas t C h a n n e l in to the Gul f of M a i n e va r ies s e a s o n a l l y a n d is m in ima l in spr ing

( R A M P et al., 1985 ) . Thi rd ly , a b o u t 5 0 k m off t he coas t , e l ve rs w o u l d e n c o u n t e r the

s e a w a r d e d g e of t he 3 0 k m w i d e inshore b ranch of t h e low sal in i ty Nova Sco t ia Cur ren t

wh ich f lows s o u t h w e s t a t a b o u t 6 km-d" ' t hen con t i nues pas t C a p e S a b l e a n d into t h e Gulf

of Ma ine , par t i cu lar ly d u r i n g late w in te r a n d ear ly sp r i ng w h e n e lve rs a re act ive ly mov ing

inshore , m ix ing w i th wa te r f r o m t h e Gul f of M a i n e be fo re f l ow ing no r th a l o n g the eas twa rd

s ide of the lower Bay of Fundy, ( S U T C L I F F E et al., 1976 ; S M I T H , 1989) . T h e Sco t ian

Shel f p rogress ive ly sha l l ows , f r o m abou t 2 0 0 m at 5 0 k m o f f sho re to 100 m at 2 0 k m and

50 m at 10 k m o f f shore , a n d t h e inshore Nova Sco t i a C u r r e n t e x t e n d s to the bo t tom

th rough m u c h of its w i d t h . A l t h o u g h e lvers sw im at s p e e d s g rea te r t han 10 c m s 1 for a t

least shor t d i s tances ( B A R B I N a n d K R U E G E R , 1994 ) , e l ve rs ma in ta i n i ng a reputed ly

op t ima l s w i m m i n g s p e e d of o n e b o d y length per s e c o n d ( W E I H S , 1 9 7 3 ; H I C K M A N , 1981)

or abou t 6 c m s 1 (5 km-d ' 1 ; S c o t i a - F u n d y e lvers a v e r a g e a b o u t 5 8 m m T L ) , cou ld be

advec ted p e r h a p s 4 0 k m (or by p e r h a p s 120 k m at 2 c m s 1 ) to t h e s o u t h w e s t whi le

t rans i t ing th is z o n e of t h e Sco t ia -She l f .

T h e o b s e r v e d h i g h - t o - m o d e r a t e e lver dens i t i es in t h e lower Bay of Fundy, N.S. a n d

N.B., reg ions a n d the M a y p e a k in e lver a b u n d a n c e in the lower Bay of Fundy, N.B. area

a re cons is ten t w i th the res idua l cu r ren ts c i rcu la t ing c o u n t e r - c l o c k w i s e a r o u n d the Bay of

Fundy ( G R E E N B U R G , 1984) . A m e r i c a n s h a d (Alosa s a p i d i s s i m a ) m ig ra t i ng t h r o u g h the

Bay of Fundy a l so fo l low t h e coun te r - c l ockw ise pa th of t he res idua l cur ren t ( D A D S W E L L

et al., 1987) . T h e low e lver dens i t i es in the M i n a s Bas in a n d C h i g n e c t o Bay a reas of the

upper Bay of Fundy m a y resul t f r o m thei r pos i t ion off t he m a i n cu r ren t path and turbu lent

t idal f l ush ing . Ear ly e lver ar r iva ls to the lower Bay of F u n d y m a y p rog ress a r o u n d t h e Bay

unti l wa te r t e m p e r a t u r e s r ise suf f ic ient ly to c u e r iver e n t r a n c e ( M A R T I N , 1995) .

A geog raph i c c l ine in e lver run t im ing may be l inked to d i f fe rences in coas ta l and

s t r e a m wa te r t e m p e r a t u r e s . Inshore coas ta l wa te r t e m p e r a t u r e s i n c r e a s e d , b e t w e e n Apri l

a n d June , f r om wes t (Sou th Sho re ) to eas t (Eas te rn S h o r e ) a l o n g the At lant ic coas t of

Nova Sco t ia ( W A L K E R et al., 1986) . S e a t e m p e r a t u r e s of 4 °C w e r e f i rst r eco rded dur ing

late Apr i l off t he S o u t h S h o r e a rea , abou t m i d - M a y in the Hal i fax a rea , m idway a long the

coast , a n d ea r l y - to -m id J u n e in the n o r t h e a s t e r n por t ion of t h e Eas te rn S h o r e area.

Coas ta l w a t e r s in the Bay of F u n d y are w a r m e r in w in te r a n d ea r l y sp r i ng at the mou th

than at the h e a d of t he Bay w i th a reversal occu r r i ng by s u m m e r ( G R E E N B U R G , 1984) .

E lvers m a y o c c u r i nshore w a t e r s for w e e k s or e v e n m o n t h s be fo re they act ive ly

en ter a s t r eam ( H A R O a n d K R U E G E R , 1988) . T h e t ime d i f fe rence b e t w e e n e lver arr ival in

es tua r ine w a t e r s a n d the s tar t of u p s t r e a m m o v e m e n t m a y ref lect bo th a phys io log ica l

ad jus tmen t pe r i od p r e p a r a t o r y to en te r i ng f r eshwa te r ( T E S C H , 1977 ) a n d t im ing of t h e cue

to beg in u p s t r e a m m o v e m e n t p rov i ded by r is ing wa te r t e m p e r a t u r e s a n d fal l ing water

levels ( H A R O a n d K R U E G E R , 1 9 8 8 ; M A R T I N , 1 9 9 5 ) . R ive rs usua l l y w a r m s o o n e r and

Bull. Fr. Pêche Piscic. (1998) 349 :103-116 — 114 —

s p r i n g runof f beg ins ear l ie r a l ong t h e south s h o r e of Nova Sco t ia a n d lower Bay of Fundy

s h o r e t h a n e l s e w h e r e in the Sco t i a -Fundy a r e a ( D Z I K O W S K I , 1984) , cons is ten t wi th the

s t r e a m e n t r a n c e of e lvers du r i ng mid- to- late Apr i l a long the Sou th S h o r e a n d lower Bay of

F u n d y s h o r e s of N o v a Sco t i a a n d ear ly - to -mid May a long the Eas te rn Shore , N.S. In 1996,

m e a n da i ly wa te r t e m p e r a t u r e s in the East r ivers, Ches te r a n d S h e e t Ha rbou r ( located in

t h e cen t ra l po r t ion of the At lant ic coas t of Nova Scot ia abou t 140 k m apar t ) f irst r eached

1 0 °C o n s im i la r da tes ( M a y 5-7) but the first elver f i shery ca t ches o c c u r r e d in t idal wa te rs

o n Apr i l 2 7 (ve rsus M a y 26) a n d the first peak in e lver t rap c a t c h e s occu r red at, or just

u p s t r e a m of the t ida l l imit, o n M a y 18 (versus June 5) in the m o r e sou ther ly East River,

C h e s t e r ( J E S S O R 1997 ) . A l t h o u g h r iver water t empe ra tu res a n d d i scha rge may act as

g a t i n g f ac to rs to e lver u p s t r e a m movemen t , the t im ing of e lver arr iva l inshore , is l ikely

c o n t r o l l e d by o c é a n o g r a p h i e cond i t i ons , wh ich may va ry regional ly.

C O N C L U S I O N S

T h e e lver f i shery of t he Sco t ia -Fundy a r e a of Nova Sco t ia a n d N e w Brunswick has

g r o w n subs tan t ia l l y in the past four yea rs but may n o w have n e a r e d its l imit b e c a u s e of the

c o n t r o l s p l a c e d on the ex is t ing f ishery. Future g rowth may d e p e n d on ex tens ion of the

f i s h e r y to n e w a reas or to r e d u c e d restr ict ion in ex is t ing a reas . T h e f i shery has p rov ided

v a l u a b l e ins igh t into the s e a s o n a l a n d regional d is t r ibut ion of e lver a b u n d a n c e a n d , in

f u t u re , m a y reveal t h e d e g r e e of na tura l variabi l i ty in elver a b u n d a n c e both annua l l y and

reg iona l l y w i t h i n the Mar i t ime Prov inces .

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I t h a n k B. P E T R I E for i n fo rmat ion and insight into the o c é a n o g r a p h i e p rocesses of

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