2008 Nass Stock Assessment Update - Friday, September 5, 2008

ATTACHED IS A STOCK ASSESSMENT SUMMARY UPDATE FOR THE NASS RIVER (PDF FORMAT)
FROM THE NISGA'A FISHERIES AND WILDLIFE DEPARTMENT OF NISGA'A LISIMS
GOVERNMENT.  SAYT-K'IL'IM-GOOT.

NASS FISHWHEEL OPERATIONAL NOTES:

FISHWHEEL
ASSESSMENT DATA UP TO THURSDAY 4 SEPTEMBER 2008. 

GW
FISHWHEELS (TEST FISHERY - 15TH YEAR):  FISHWHEELS 1 AND 2 WERE STARTED ON 5
JUNE FOR TAGGING AND HISTORICAL CATCH INDEX ASSESSMENTS FOR SALMON AND
STEELHEAD. 

FISHWHEELS 1 AND 2 ARE OPERATING AT A WATER LEVEL OF 0.9
M THAT IS BELOW AVERAGE FOR DATE.  AVERAGE WATER LEVEL FROM 1992 TO 2007 WAS
1.6 M FOR DATE.

FISHWHEELS 1 AND 2 ARE SCHEDULED TO BE
SHUTDOWN FOR THE SEASON ON SATURDAY 6 SEPTEMBER.
 
ALL FISH CAUGHT IN
THE GITWINKSIHLKW FISHWHEELS HAVE BEEN RELEASED. 

GREASE HARBOUR
FISHWHEELS:  THREE FISHWHEELS OPERATE AT GREASE HARBOUR FOR IN-SEASON MARK
RECAPTURE TAG RECOVERIES.  THE FISHWHEEL START-UP DATES WERE: 11 JUNE (FW5), 12
JUNE (FW6) AND 13 JUNE (FW3). 
 
THREE FISHWHEELS ARE CURRENTLY
OPERATIONAL.  GREASE HARBOUR FISHWHEELS ARE SCHEDULED TO BE SHUTDOWN FOR THE
SEASON ON SATURDAY 6 SEPTEMBER.
 
ALL FISH CAUGHT IN THE GREASE
HARBOUR FISHWHEELS HAVE BEEN RELEASED. 

SINCE ONLY THREE FISHWHEELS
ARE FISHING AT GREASE HARBOUR COMPARED TO FOUR SINCE 2000, TOTAL FISHWHEEL
CATCHES IN 2008 AS REPORTED BELOW WILL NOT BE DIRECTLY COMPARABLE WITH FISHWHEEL
CATCH AVERAGES FROM 2000 TO 2007.  CATCH AVERAGE COMPARISONS AT THE GW
FISHWHEELS WILL BE COMPARABLE AND ARE PROVIDED IN ATTACHMENT. 

NASS SOCKEYE SALMON:
THE NASS SOCKEYE RUN SIZE
ESTIMATE TO GITWINKSIHLKW TO DATE (191,343) IS TRACKING BELOW AVERAGE
(278,000) FOR DATE BASED ON A MEAN RUN SIZE TO GITWINKSIHLKW OF
281,000 FROM 1994 TO 2007.  NOTE THAT THE RUN SIZE IS SMALLER THAN THE
LAST UPDATE DUE TO MARK-RATE ADJUSTMENTS FROM DATA COLLECTED AT THE GREASE
HARBOUR FISHWHEELS. 

THE RUN SIZE ESTIMATE IS A COMBINATION OF
MARK-RECAPTURE AND HISTORICAL CATCH INDICES METHODS.  THE MARK RECAPTURE
ESTIMATES WILL CHANGE OVER A 5-DAY PERIOD DUE TO MARK RATES STABILIZING AT
GREASE HARBOUR AS FISH TAGGED AT GITWINKSIHLKW PASS THE UPSTREAM GREASE HARBOUR
FISHWHEEL SITES OVER A 5-DAY PERIOD.  AFTER THE MARK RATE STABILIZES, THE DAILY
ESTIMATE IS BETTER AT PREDICTING ACTUAL CATCH EFFICIENCIES AT THE GW FISHWHEELS
THAN THE HISTORICAL INDICES AND AN ADJUSTMENT WILL BE MADE TO THE PRELIMINARY
ESTIMATES. AS SUCH WE USE HISTORICAL CATCH EFFICIENCIES DURING THE 5-D
FLUCTUATING PERIOD WHILE MARK RECAPTURE ESTIMATES ARE STABILIZING FOR LESS
FLUCTUATING ESTIMATES THAT ARE REPORTED.  CURRENTLY, MARK RECAPTURE ESTIMATES
ARE FINAL TO 30 AUGUST AND LATER DATES WILL FLUCTUATE FROM 31 AUGUST
TO 6 SEPTEMBER AS ADDITIONAL CATCH AND TAG RECOVERY DATA BECOME AVAILABLE
FROM THE GREASE HARBOUR FISHWHEELS.   A SPREADSHEET OF THE CALCULATIONS AND
RANGE OF ESTIMATES IS PROVIDED IN THE ATTACHMENT.

THE RUN SIZE TARGET FOR
NASS SOCKEYE TO GITWINKSIHLKW IS ~218,000 FOR 2008 BASED ON HARVESTS
PROJECTED ABOVE GITWINKSIHLKW.  NISGA'A FISHERIES IS ESTIMATING THAT
APPROXIMATELY 99% (93-07 MEDIAN) OF THE SOCKEYE RUN HAS PASSED
GITWINKSIHLKW TO DATE.  USING FINAL MARK-RECAPTURE ESTIMATES TO 30
AUGUST, CURRENT FORECAST METHODS ARE PREDICTING THAT THE FINAL RUN SIZE
PROJECTION WILL NOT REACH THE TARGET WITH ESTIMATES RANGING FROM 194,000
(MEAN RUN TIMING METHOD - RANGE 192,000-196,000) TO 197,000 (IN-SEASON TO
FINAL METHOD).  HOWEVER, THE MINIMUM ESCAPEMENT TARGET LEVEL HAS BEEN ACHIEVED
FOR 2008 FOR NASS SOCKEYE.  IN ADDITION,  PRELIMINARY MARK RECAPTURE DATA AT
MEZIADIN FISHWAY SUGGEST THAT THE IN-SEASON RUN SIZE (AND FORECAST) ESTIMATES AT
GITWINKSIHLKW ARE CONSERVATIVE AND MAY BE ~10-15% HIGHER (~20,000 TO 30,000
SOCKEYE) ASSUMING A 18-D LAG AND 20% MARK LOSS RATE.

THE IN-SEASON
NET ESCAPEMENT ESTIMATE FOR NASS SOCKEYE TO DATE IS 174,323.  THE NET
ESCAPEMENT TARGET IS 200,000 (160,000 TO MEZIADIN RIVER AND 40,000 TO
NON-MEZIADIN SYSTEMS).  

MEZIADIN FISHWAY OPENED ON 1 JULY FOR
ESCAPEMENT COUNTS TO RIVER.  TOTAL COUNTS OF SOCKEYE AT MEZIADIN TO 4
SEPTEMBER ARE:  141,849 ADULTS (4594 TAGS) AND 2185 JACKS.  THE 2008
CUMULATIVE ADULT COUNT TO DATE IS BELOW AVERAGE (152,000) BASED ON MEAN
COUNTS AT THE MEZIADIN FISHWAY FROM 1994 TO 2007.  THE AVERAGE COUNT OF ADULT
SOCKEYE FROM 1994 TO 2007 WAS 170,000.  CURRENT FORECAST METHODS ARE
RANGING FROM 151,000 (ADJUSTED FISHWHEEL MEAN RUN TIMING METHOD ASSUMING
THE MAXIMUM MEZIADIN STOCK PROPORTION (85%)) TO 156,000 (MEZIADIN
MEAN RUN TIMING METHOD) OF REACHING THE ESCAPEMENT TARGET (160,000). 
NISGA'A FISHERIES IS ESTIMATING THAT ~91% OF THE MEZIADIN SOCKEYE RUN HAS
REACHED THE FISHWAY TO DATE BASED ON MEAN COUNTS FROM 1990 TO
2007.

NISGA'A FISHERIES IS USING A PRELIMINARY TOTAL RETURN TO CANADA
(TRTC) ESTIMATE FOR NASS SOCKEYE OF BETWEEN ~315,000 (IN-SEASON) AND
350,000 (PRE-SEASON) FOR TRACKING THE NISGA'A ENTITLEMENT OF NASS SOCKEYE
THAT IS RANGING BETWEEN 43,000 AND 52,000.  TRTC RETURNS ARE
INFLUENCED BY ALASKAN CATCHES WHICH ARE CURRENTLY BELOW AVERAGE FOR DATE BUT
GILLNET AND SEINE FISHERIES CONTINUE TO OCCUR IN DISTRICTS 101 TO 104.  THE 2008
TRTC RETURN WAS PROJECTED TO BE BELOW AVERAGE (666,000) BASED ON TRTC
RETURNS FROM 1994 TO 2007. 

THE IN-SEASON NISGA'A CATCH ESTIMATE OF NASS
SOCKEYE IN 2008 IS 45,409.  THE TOTAL ESTIMATE INCLUDES FSC CATCH
(27,681) AND INDIVIDUAL MARINE SALE FISHERY CATCH (17,728).  THE
ANNUAL TOTAL AVERAGE NISGA'A FSC HARVEST FROM 2000 TO 2007 OF NASS
SOCKEYE WAS 26,000.   THE NISGA’A CATCH MONITORING PROGRAM ENDED
ON 23 AUGUST.  THE TOTAL CATCH ESTIMATE INCLUDES AN ESTIMATE OF SOCKEYE CAUGHT
AFTER THE END OF THE PROGRAM BASED ON AVERAGE CATCHES IN YEARS WHEN MONITORING
WAS CONDUCTED AFTER 23 AUGUST.

NISGA'A FOOD FISH (FSC) HARVESTING IS
OPEN FOR ALL SPECIES.  GIVEN THAT THE TOTAL FSC AMOUNT WAS PROJECTED TO NOT
EXCEED THE TOTAL NISGA'A ENTITLEMENT ESTIMATE FOR 2008, THE REMAINING
ENTITLEMENT (~20,000) WAS AVAILABLE FOR SALE FISHERIES.  THE DIRECTOR OF NISGA'A
FISHERIES AND WILDLIFE OPENED THE NISGA'A MARINE INDIVIDUAL SALE FISHERY FOR
HARVESTING NASS SOCKEYE AS SALE FISHERIES FOR FOUR 48-HR OPENINGS FROM 16 JULY
TO 1 AUGUST THAT CAUGHT A TOTAL OF 17,728 SOCKEYE.   AS A RESULT OF THE CURRENT
ASSESSMENTS OF RUN SIZE AND NISGA'A ENTITLEMENT OF NASS SOCKEYE, THE MARINE
INDIVIDUAL SALE FISHERY CLOSED FOR THE REMAINDER OF 2008.  IN-RIVER SALE
FISHERIES DID NOT OPEN FOR 2008 INCLUDING HARVESTING FROM THE FISHWHEELS.   ALL
FISH WERE RELEASED FROM THE FISHWHEELS.

FOUR NISGA'A INDIVIDUAL SALE
FISHERIES OCCURRED IN 2008 (16-17 JULY [17 BOATS]; 17-18 JULY [17
BOATS]; 23-25 JULY [17 BOATS]; 30 JULY - 1 AUGUST [~21 BOATS]) IN
AREA 3-12.  TOTAL CATCHES IN THE NISGA'A MARINE SALE FISHERIES WERE:   17,728
SOCKEYE; 3,438 PINK; 793 COHO AND 276 CHUM.  

THE NISGA'A NATION
PASSED A RESOLUTION AT THE SPECIAL ASSEMBLY IN MAY 2008 RECOMMENDING THE CLOSURE
OF THE GENERAL COMMERCIAL FISHERY IN AREA 3-12 DUE TO PRE-SEASON CONSERVATION
CONCERNS OF NASS SOCKEYE AND CHINOOK.  DFO KEPT AREA 3-12 CLOSED TO 20
JULY DUE TO THE POOR RETURN OF CHINOOK AND ENSURING GOOD ESCAPEMENT OF NASS
SOCKEYE INTO THE RIVER AT THE TIME.  DFO OPENED AREA 3-12 TO THE GENERAL
COMMERCIAL FISHERY STARTING ON 21 JULY WITH THE MAJORITY OF NASS CHINOOK
THROUGH THE MARINE WATERS AND THE NASS SOCKEYE RUN TRACKING ON TARGET OF
REACHING THE ESCAPEMENT GOAL AT THE TIME.   AREA 3-12 HAS BEEN CLOSED SINCE
27 JULY AND THE REST OF AREA 3 SINCE 29 JULY.  A TOTAL OF 7633
SOCKEYE WERE CAUGHT IN AREA 3 BETWEEN 21 JULY AND 29 JULY.  DFO HAVE
ANNOUNCED A GENERAL CLOSURE OF AREAS 3 TO 6 FOR THE REMAINDER OF 2008 TO SEINES
AND GILLNETS.

AREA 3 FISHERIES CONDUCTED IN 2008 HAVE BEEN 7
GILLNET [24 JUNE (170 BOATS), 1 JULY (209 BOATS), 7 JULY (174 BOATS), 14
JULY (179 BOATS), 15 JULY (5 BOATS), 21 JULY (16) AND 27 JULY (33)] AND 4
SEINE (14 JULY (13 BOATS), 15 JULY (5 BOATS), 21 JULY (13 BOATS) AND 29 JULY
(7 BOATS)) FISHERIES.  TOTAL COMMERCIAL HARVEST ESTIMATES IN AREA 3
ARE:   37,501 SOCKEYE; 17,972 PINK; 14,135 CHUM AND 405 CHINOOK
(SOURCE OF DATA IS FROM DFO PRINCE RUPERT FISHERIES MANAGEMENT).  

ALASKAN GILLNET FISHERIES IN DISTRICTS 101 (TREE POINT) AND 106 (SUMNER
AND UPPER CLARENCE) BEGAN ON 15 JUNE AND 8 JUNE, RESPECTIVELY. 
ALASKAN SEINE FISHERIES OPENING DATES WERE:   DISTRICTS 101 (LOWER
CLARENCE/REVILLA; OPENED ON 6 JULY), 102 (MIDDLE CLARENCE; OPENED
ON 22 JUNE), 103 (CORDOVA; OPENED 24 JULY) AND 104
(NOYES/DALL; OPENED ON 6 JULY).  LATEST ALASKAN OPENINGS ARE:  GN (101
AND 106) – 7-11 SEPTEMBER; AND SN (101-104) – 30-31 AUGUST (101-104);
10 SEPTEMBER (102 & 103).

TOTAL IN-SEASON CATCH ESTIMATE OF
SOCKEYE IN SOUTHEAST ALASKAN FISHERIES IS 126,682 BASED ON DATA TO 4
SEPTEMBER ON THE ADFG WEBSITE AND IS INCOMPLETE CATCH REPORTING FOR
WEEK 36 (ENDS 6 SEPTEMBER).  REPORTED CATCHES ARE WELL BELOW AVERAGE TO
DATE.  THE AVERAGE CATCH OF SOCKEYE IN SOUTHEAST ALASKAN FISHERIES IS
714,000 SOCKEYE FROM 1999 TO 2007. 

OF THE TOTAL ALASKAN CATCH
OF SOCKEYE, NISGA'A FISHERIES IS ESTIMATING APPROXIMATELY ~35,500 ARE
NASS SOCKEYE BASED ON AVERAGE STOCK % DATA (1982-98) AND IS BELOW AVERAGE TO
DATE.  AVERAGE CATCH OF NASS SOCKEYE IS 165,000 FROM 1999 TO
2007.


NASS CHINOOK SALMON:
THE NASS CHINOOK RUN SIZE ESTIMATE
TO GITWINKSIHLKW (14,161) IS BELOW AVERAGE FOR DATE (22,500) BASED
ON A MEAN RUN SIZE TO GITWINKSIHLKW OF 22,500 FROM 1994 TO 2007.  THE RUN
SIZE TARGET FOR NASS CHINOOK TO GITWINKSIHLKW IS 17,000 DEPENDING ON
HARVESTS PROJECTED ABOVE GITWINKSIHLKW.  THE IN-SEASON TRACKING OF THE NASS
CHINOOK RUN TO GITWINKSIHLKW PREDICTED ~14,000 [MEAN RUN TIMING METHOD
AND IN-SEASON TO FINAL METHOD] AS THE FINAL IN-SEASON RUN SIZE TOTAL TO
GITWINKSIHLKW.  THE 2008 RETURN TO DATE IS THE THIRD WORST ON RECORD SINCE THE
START OF THE NISGA'A FISHERIES PROGRAM IN 1992.  NISGA'A FISHERIES IS ESTIMATING
THAT 100% (93-07 MEDIAN) OF THE RUN HAS PASSED GITWINKSIHLKW TO DATE. 

THE IN-SEASON NET ESCAPEMENT ESTIMATE FOR NASS CHINOOK IS
12,951.  THE NET ESCAPEMENT TARGET FOR NASS CHINOOK ABOVE GREASE HARBOUR
IS 15,000.   A PRELIMINARY REVIEW OF MARK-RECAPTURE DATA AT MEZIADIN
FISHWAY IS INDICATING THAT IN-SEASON ESTIMATES MAY BE CONSERVATIVE AND FINAL
POST-SEASON ESTIMATES MAY BE HIGHER SUGGESTING A POSSIBILITY THAT THE ESCAPEMENT
TARGET WAS REACHED IN 2008.  NOTE THAT THE MINIMUM ESCAPEMENT TARGET FOR
NASS CHINOOK HAS BEEN ACHIEVED IN 2008.

TOTAL COUNTS OF CHINOOK AT
MEZIADIN FISHWAY TO 4 SEPTEMBER ARE:  488 ADULTS (17 TAGS) AND 59
JACKS.  THE 2008 CUMULATIVE ADULT COUNT TO DATE IS ABOVE AVERAGE
(399) BASED ON MEAN COUNTS AT THE MEZIADIN FISHWAY FROM 1994 TO 2007. 
THE AVERAGE COUNT OF ADULT CHINOOK AT MEZIADIN FISHWAY FROM 1994 TO 2007 WAS
480. THE FISHWHEEL MEAN-RUN TIMING FORECAST IS PREDICTING 590
CHINOOK TO REACH THE FISHWAY BASED ON CURRENT ESCAPEMENT PASSED GW AND ESTIMATED
STOCK COMPOSITION (4.7%).  OTHER FORECASTS RANGE BETWEEN 560
(IN-SEASON TO FINAL MEZIADIN COUNT METHOD) AND 580 (MEZIADIN MEAN RUN
TIMING METHOD).  NISGA'A FISHERIES IS ESTIMATING THAT ~85% OF THE
MEZIADIN CHINOOK RUN HAS PASSED THE FISHWAY TO DATE BASED ON MEAN COUNTS FROM
1990 TO 2007.   MARK-RECAPTURE SURVEYS FOR FINAL ESCAPEMENT ESTIMATES ARE ALSO
PLANNED AT KWINAGEESE AND DAMDOCHAX RIVERS IN SEPTEMBER 2008.

THE
KINCOLITH VIDEO-COUNTING FENCE BEGAN OPERATION ON 11 JUNE FOR COLLECTING
ESCAPEMENT DATA FOR THE KINCOLITH RIVER AND PROVIDING AN INDEX OF ESCAPEMENT TO
COASTAL STREAMS IN AREA 3.  NET UPSTREAM COUNTS AT THE WEIR TO 2
SEPTEMBER ARE:  846 CHINOOK (177 AFC AND 39 BROODSTOCK), 874 PINK,
57 COHO AND 15 CHUM.  OTHER WEIR COUNTS TO DATE ARE: 13 STEELHEAD (5 UP 
& 8 DOWN) AND 6 CUTTHROAT/RAINBOW TROUT (5 UP & 1 DOWN IN JULY; <50
CM AND SEA RUN; FINAL ID CONFIRMED AT END OF SEASON).  THE CURRENT COUNT OF
CHINOOK PASSING THE WEIR IS BELOW THE AVERAGE COUNT (1114) FOR THE DATE
FROM PAST OPERATIONS (2001, 2002, 2005-2007).  HOWEVER, NISGA'A FISHERIES
PROJECTED THAT THE ESCAPEMENT GOAL (700) WOULD BE REACHED IN 2008 BASED
ON THE RUN SIZE FORECAST METHOD WHICH IS CURRENTLY ESTIMATING ~858 (RANGE
853-864) FROM MEAN RUN TIMING FROM PAST OPERATIONS (2001, 2002, 2005-2007). 
NISGA'A FISHERIES IS ESTIMATING THAT ~99% OF THE KINCOLITH CHINOOK RUN
HAS PASSED THE WEIR TO DATE BASED ON THE RECONSTRUCTED MEAN RUN
TIMING.

NISGA'A FISHERIES IS USING A PRELIMINARY TRTC ESTIMATE FOR NASS
CHINOOK OF BETWEEN 20,500 (IN-SEASON) AND 21,000 (PRE-SEASON) FOR
TRACKING THE NISGA'A ENTITLEMENT OF NASS CHINOOK.  THE 2008 TRTC ESTIMATES
FORECASTED FOR A BELOW AVERAGE RETURN (36,000) BASED ON TRTC RETURNS FROM
1994 TO 2007.  UNCERTAINTY OF MARINE COMMERCIAL AND RECREATIONAL CATCHES OF NASS
CHINOOK MAKE IT DIFFICULT TO ACCURATELY ESTIMATE IN-SEASON TRTC ESTIMATES FOR
NASS CHINOOK. HOWEVER, BASED ON THE IN-SEASON TRTC ESTIMATES FOR 2008, THE
NISGA'A ENTITLEMENT OF NASS CHINOOK IS ~4000.  A PORTION OF THE
CUMULATIVE UNDERAGE OF 3300 FROM PAST YEAR'S MANAGEMENT UNCERTAINTY MAY
BE NEEDED TO FULFILL NISGA'A FSC NEEDS IN 2008 WHICH ON AVERAGE TOTALS
6200 NASS CHINOOK.  THE FINAL ENTITLEMENT TARGET IS EXPECTED TO RANGE
BETWEEN 4000 AND 5000.

THE IN-SEASON TOTAL NISGA'A CATCH ESTIMATE
OF NASS CHINOOK IN 2008 IS 4342 (INCLUDING ANGLING HARVESTS ON KINCOLITH
RIVER) AND BELOW AVERAGE (00-07).  THE ANNUAL TOTAL AVERAGE NISGA'A
FSC HARVEST OF NASS CHINOOK FROM 2000 TO 2007 WAS 6200.  THE
NISGA’A CATCH MONITORING PROGRAM ENDED ON 23 AUGUST.  THE TOTAL ESTIMATE
INCLUDES AN ESTIMATE OF CHINOOK CAUGHT AFTER THE END OF THE PROGRAM BASED ON
AVERAGE CATCHES IN YEARS WHEN MONITORING WAS CONDUCTED AFTER 23 AUGUST.  NO
CHINOOK WERE PERMITTED FOR SALE IN ANY OF THE INDIVIDUAL SALE FISHERIES THAT
WERE CONDUCTED IN 2008.

NASS COHO SALMON:
THE NASS COHO RUN
SIZE ESTIMATE TO GITWINKSIHLKW (88,634) IS TRACKING ABOVE AVERAGE
(69,500) FOR DATE BASED ON A MEAN RUN SIZE TO GITWINKSIHLKW OF
76,000 FROM 1994 TO 2007.  THE RUN SIZE TARGET FOR NASS COHO TO
GITWINKSIHLKW IS ~50,000 DEPENDING ON HARVESTS PROJECTED ABOVE
GITWINKSIHLKW AND DURING TYPICAL GITWINKSIHLKW FISHWHEEL OPERATION (JUNE TO
EARLY-MID SEPTEMBER).  NISGA'A FISHERIES IS ESTIMATING THAT ~93% (93-07
MEDIAN) OF THE RUN HAS PASSED GITWINKSIHLKW TO DATE BASED ON TYPICAL OPERATION
OF FISHWHEELS.  THE RUN SIZE ESTIMATES ARE CONSERVATIVE FOR MIDDLE TO UPPER NASS
COHO STOCKS AS COHO CONTINUE TO PASS THE FISHWHEELS AFTER OPERATIONS. 

THE RUN SIZE ESTIMATES ARE A COMBINATION OF MARK-RECAPTURE AND
HISTORICAL CATCH INDICES METHODS.  NOTE THAT MARK RECAPTURE ESTIMATES WILL
CHANGE OVER A 7-DAY PERIOD DUE TO MARK RATES STABILIZING AT GREASE HARBOUR AS
COHO TAGGED AT GITWINKSIHLKW PASS THE UPSTREAM GREASE HARBOUR FISHWHEEL SITES
OVER THE 7-DAY PERIOD.  A SPREADSHEET OF THE CALCULATIONS AND RANGE IN ESTIMATES
IS PROVIDED IN THE ATTACHMENT.

THE IN-SEASON NET ESCAPEMENT ESTIMATE FOR
NASS COHO IS 88,088.  THE NET ESCAPEMENT TARGET FOR NASS COHO ABOVE
GREASE HARBOUR IS ~41,000 DURING TYPICAL OPERATIONS OF THE GITWINKSIHLKW
FISHWHEELS FROM JUNE TO FIRST OR SECOND WEEK OF SEPTEMBER.   THE NET
ESCAPEMENT TARGET HAS BEEN ACHIEVED IN 2008 BASED ON CURRENT IN-SEASON
ESTIMATES.  CURRENT FORECAST ESTIMATES OF ESCAPEMENT ARE PREDICTING FROM
96,000 (IN-SEASON TO FINAL ESTIMATE METHOD) TO 95,000 (FISHWHEEL
MEAN RUN TIMING; RANGE 89,000-101,000) TO REACH GITWINKSIHLKW.

TOTAL
COUNTS OF COHO AT MEZIADIN FISHWAY TO 4 SEPTEMBER ARE: 463 ADULTS (0
TAGS) AND 18 JACKS. THE 2008 CUMULATIVE ADULT COUNT TO DATE IS CURRENTLY
BELOW AVERAGE (806) BASED ON MEAN COUNTS AT THE MEZIADIN FISHWAY FROM
1994 TO 2007.  THE AVERAGE COUNT OF ADULT COHO AT MEZIADIN FISHWAY FROM 1994 TO
2007 WAS 3600.

NISGA'A FISHERIES IS USING A PRELIMINARY TRTC
ESTIMATE FOR NASS COHO OF BETWEEN 104,000 (PRE-SEASON) AND 175,000
(IN-SEASON) FOR TRACKING THE NISGA'A ENTITLEMENT OF NASS COHO THAT IS CURRENTLY
RANGING BETWEEN 8,000 AND 14,000.  THE 2008 IN-SEASON TRTC
ESTIMATE IS CURRENTLY PROJECTING FOR AN AVERAGE OR ABOVE AVERAGE RETURN
(162,000) BASED ON TRTC RETURNS FROM 1994 TO 2007.

THE IN-SEASON
TOTAL NISGA'A CATCH ESTIMATE OF NASS COHO IN 2008 IS 3069.  THE TOTAL
ESTIMATE INCLUDES FSC CATCH (2276) AND INDIVIDUAL MARINE SALE FISHERY
CATCH (793).  THE NISGA’A CATCH MONITORING PROGRAM ENDED ON 23 AUGUST. 
THE TOTAL ESTIMATE INCLUDES AN ESTIMATE OF COHO CAUGHT AFTER THE END OF THE
PROGRAM BASED ON AVERAGE CATCHES IN YEARS WHEN MONITORING WAS CONDUCTED AFTER 23
AUGUST.

NASS PINK SALMON:
THE FISHWHEEL CATCH OF PINK
SALMON (1908) TO DATE IS WELL BELOW THE MEAN CATCH (16,000) FOR
EVEN-YEAR RETURNS FROM 2000 TO 2007.

NISGA'A FISHERIES DOWNSIZED
THE PRE-SEASON TRTC ESTIMATE (569,000) TO ~285,000 (~1/2 OF
PRE-SEASON ESTIMATE) ON 15 AUGUST FOR NASS PINKS BASED ON DATA FROM DFO
(POOR ABUNDANCES DETECTED IN STREAM WALK SURVEYS IN AREA 3), BELOW AVERAGE
NUMBERS AT THE FISHWHEELS AND EXTREMELY LOW NUMBERS (<1000) AT THE KINCOLITH
WEIR (AVERAGE RETURN OF EVEN-YR PINKS IS 9,000).  AS A RESULT OF
DOWNSIZING, THE NISGA’A ENTITLEMENT OF NASS PINK IS ~10,000 AND IS MUCH
SMALLER THAN THE PRE-SEASON ESTIMATE (54,000).  THE 2008 IN-SEASON TRTC
ESTIMATE IS FORECASTING WELL BELOW AVERAGE (524,000) BASED ON TRTC
RETURNS OF EVEN YEAR PINKS FROM 1994 TO 2007.  THE 2008 RETURN APPEARS TO BE
SIMILAR TO THE LAST NASS AREA PINK SALMON EVEN-YR RETURN (230,000) IN
2006. 

NOTE THAT PRE-SEASON AND IN-SEASON FORECASTING OF NASS AREA
PINKS ARE POORLY DEVELOPED FOR AREA 3 CURRENTLY.  NISGA’A FISHERIES IS
DEVELOPING IN-SEASON METHODS WITH DFO FOR BETTER PREDICTING MAGNITUDE OF RETURNS
IN THE FUTURE BASED ON FISHWHEEL MEAN CATCHES, KINCOLITH WEIR COUNTS AND ANY
STREAM SURVEY INFORMATION THAT CAN BE COLLECTED DURING THE SEASON TO AID IN
MANAGING NASS AREA PINKS AND TRACKING THE NISGA’A ENTITLEMENT. 

THE
IN-SEASON TOTAL NISGA'A CATCH ESTIMATE OF NASS PINK IN 2008 IS 4324. THE
TOTAL ESTIMATE INCLUDES FSC CATCH (886) AND INDIVIDUAL MARINE SALE
FISHERY CATCH (3438).  THE NISGA’A CATCH MONITORING PROGRAM ENDED ON 23
AUGUST.  THE TOTAL CATCH ESTIMATE INCLUDES AN ESTIMATE OF PINKS CAUGHT AFTER THE
END OF THE PROGRAM BASED ON AVERAGE CATCHES IN YEARS WHEN MONITORING WAS
CONDUCTED AFTER 23 AUGUST.

NASS CHUM SALMON:
THE FISHWHEEL
CATCH OF CHUM (47) TO DATE IS BELOW THE MEAN CATCH (143) LEVEL
FROM 2000-2007.

NISGA'A FISHERIES DOWNSIZED THE PRE-SEASON TRTC ESTIMATE
(90,000) TO ~21,000 (LOW RETURN ESTIMATE FROM 2007) ON 15
AUGUST FOR NASS AREA CHUMS BASED ON DATA FROM DFO (POOR ABUNDANCES DETECTED
IN STREAM WALK SURVEYS AT STAGOO CREEK), BELOW AVERAGE NUMBERS AT THE FISHWHEELS
AND EXTREMELY LOW NUMBERS THAT HAVE PASSED THE KINCOLITH WEIR (<20 FISH).  AS
A RESULT, THE NISGA’A ENTITLEMENT OF NASS AREA CHUM HAS BEEN DOWNSIZED FROM
7000 (PRE-SEASON) TO ~1680 (IN-SEASON).  THE 2008 IN-SEASON TRTC
ESTIMATE OF NASS CHUMS IS FORECASTING WELL BELOW AVERAGE (91,000) BASED
ON TRTC RETURNS FROM 1994 TO 2007.  PRELIMINARY ASSESSMENT DATA COLLECTED TO
DATE FROM STREAM SURVEYS SUGGEST THAT THE MINIMUM ESCAPEMENT GOAL
(30,000) MAY NOT BE REACHED FOR NASS AREA CHUMS IN 2008.

NOTE
THAT PRE-SEASON AND IN-SEASON FORECASTING OF NASS AREA CHUMS ARE POORLY
DEVELOPED FOR AREA 3.  NO RELIABLE METHODS ARE CURRENTLY AVAILABLE TO ESTIMATE
ESCAPEMENT DURING THE SEASON, TRACK THE STATUS OF THE RUN OR THE NISGA’A
ENTITLEMENT.

THE IN-SEASON TOTAL NISGA'A CATCH ESTIMATE OF NASS CHUM IN
2008 IS 495.  THE TOTAL ESTIMATE INCLUDES FSC CATCH (219) AND
INDIVIDUAL MARINE SALE FISHERY CATCH (276).  THE NISGA’A CATCH MONITORING
PROGRAM ENDED ON 23 AUGUST.  THE TOTAL CATCH ESTIMATE INCLUDES AN ESTIMATE OF
CHUMS CAUGHT AFTER THE END OF THE PROGRAM BASED ON AVERAGE CATCHES IN YEARS WHEN
MONITORING WAS CONDUCTED AFTER 23 AUGUST.

NASS SUMMER-RUN
STEELHEAD:
IN-SEASON RUN SIZE ESTIMATES OR OTHER INFORMATION
PRESENTED FOR NASS STEELHEAD ARE ONLY FOR SUMMER RUNS (I.E., DO NOT INCLUDE ANY
ESTIMATES FOR WINTER OR SPRING RUN STEELHEAD) AND ONLY COVER RETURN INFORMATION
FROM JUNE TO SEPTEMBER WHEN THE FISHWHEELS TYPICALLY OPERATE.

THE
FISHWHEEL CATCH OF STEELHEAD (821) TO DATE IS ABOVE AVERAGE (729)
FROM 2000-2007 FISHWHEEL OPERATIONS.  IN ADDITION, ONLY FIVE FISHWHEELS ARE
FISHING IN 2008 VERSUS SIX AND A GOOD PORTION OF THE STEELHEAD CATCH OCCURS AT
GREASE HARBOUR WHERE FOUR FISHWHEELS HAVE TYPICALLY OPERATED. 

THE NASS
SUMMER-RUN STEELHEAD IN-SEASON RUN SIZE ESTIMATE TO GITWINKSIHLKW (4802)
IS TRACKING BELOW AVERAGE (5600) TO DATE BASED ON A MEAN RUN SIZE TO
GITWINKSIHLKW OF 7800 DURING FISHWHEEL OPERATIONS FROM 1994 TO 2007
(BASED ON PRELIMINARY HISTORICAL RUN SIZE DATA).  HOWEVER, DURING TYPICAL
GITWINKSIHLKW FISHWHEEL OPERATION, THE PRELIMINARY RUN SIZE TARGET FOR NASS
SUMMER-RUN STEELHEAD TO GITWINKSIHLKW IS 4200 DEPENDING ON ANY LOSSES
PROJECTED ABOVE GITWINKSIHLKW AND HAS BEEN REACHED IN 2008.  NISGA'A FISHERIES
IS ESTIMATING THAT ~88% (93-07 MEDIAN) OF THE RUN HAS PASSED
GITWINKSIHLKW TO DATE BASED ON TYPICAL FISHWHEEL OPERATIONS. 

THE
IN-SEASON RUN SIZE ESTIMATE IS A COMBINATION OF MARK-RECAPTURE AND HISTORICAL
CATCH INDICES METHODS.  THE MARK-RECAPTURE ESTIMATE IS USING MARK RATES DERIVED
FROM THE COHO ASSESSMENT PROGRAM THAT ASSUMES SIMILAR CATCHABILITY BETWEEN COHO
AND STEELHEAD BASED ON SIMILAR RUN TIMING PATTERNS.  MARK-RATE SAMPLE SIZES ARE
MUCH LARGER AND MORE RELIABLE FOR COHO THAN USING STEELHEAD MARK RATE DATA. 
STEELHEAD RUN SIZE ESTIMATES WILL CHANGE OVER A 7-DAY PERIOD DUE TO COHO MARK
RATES STABILIZING AT GREASE HARBOUR AS TAGGED FISH AT GITWINKSIHLKW PASS THE
UPSTREAM GREASE HARBOUR FISHWHEEL SITES OVER A 7-DAY PERIOD.  A SPREADSHEET OF
THE CALCULATIONS AND RANGE OF ESTIMATES IS PROVIDED IN THE
ATTACHMENT.

THE IN-SEASON NET RUN SIZE ESTIMATE ABOVE GREASE HARBOUR FOR
NASS SUMMER-RUN STEELHEAD IS 4768.  THE NET RUN SIZE TARGET FOR NASS
SUMMER-RUN STEELHEAD ABOVE GREASE HARBOUR IS ~4000 DURING TYPICAL
OPERATIONS OF THE GITWINKSIHLKW FISHWHEELS.  THE PRELIMINARY NET ESCAPEMENT
TARGET HAS BEEN ACHIEVED IN 2008 BASED ON CURRENT IN-SEASON ESTIMATES.  THE
CURRENT FORECAST ESTIMATE IS PREDICTING A RETURN OF 5400 BASED ON THE IN-SEASON
TO FINAL ESTIMATE REGRESSION METHOD.

TOTAL COUNTS OF STEELHEAD AT
MEZIADIN FISHWAY TO DATE ARE: 3 ADULTS (0 TAGS).  THE 2008 CUMULATIVE
ADULT COUNT TO DATE IS ABOVE AVERAGE (1) BASED ON MEAN COUNTS AT THE
MEZIADIN FISHWAY FROM 1994 TO 2007.  THE AVERAGE COUNT OF STEELHEAD DURING
OPERATION OF MEZIADIN FISHWAY FROM 1994 TO 2007 WAS 50.

THE
IN-SEASON TOTAL NISGA'A CATCH ESTIMATE OF NASS STEELHEAD IN 2008 IS 157. 
A TOTAL OF 26 STEELHEAD WERE ALSO RELEASED ALIVE DURING THE MARINE
INDIVIDUAL SALE FISHERIES CONDUCTED BETWEEN 16 JULY AND 1 AUGUST.  THE NISGA’A
CATCH MONITORING PROGRAM ENDED ON 23 AUGUST.  THE TOTAL CATCH ESTIMATE INCLUDES
AN ESTIMATE OF STEELHEAD CAUGHT AFTER THE END OF THE PROGRAM BASED ON AVERAGE
CATCHES IN YEARS WHEN MONITORING WAS CONDUCTED AFTER 23 AUGUST.  THE AVERAGE
HARVEST OF NASS SUMMER-RUN STEELHEAD IN NISGA'A FISHERIES IS 400 FROM
1994 TO 2007.

Richard Alexander, RPBio
Nisga'a Fisheries
Stock Assessment Management Biologist
Nisga'a Lisims Government - Fisheries
& Wildlife Department
P.O. Box 228, New Aiyansh, BC, V0J 1A0
Phone: 
(250) 633-2617
Fax:        (250) 633-2971

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