Ongoing Projects to Monitor the Status and Trends of Atlantic Salmon on the Nashwaak River (Outer Bay of Fundy Region)

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1 Ongoing Projects to Monitor the Status and Trends of Atlantic Salmon on the Nashwaak River (Outer Bay of Fundy Region) Nov. 6, 2015 Ross Jones, Leroy Anderson and John Mallery

2 Outline Assessment team and roles/responsibility Salmon Populations within Maritimes Region Methods and Criteria used to Assess Populations Ongoing projects within the Nashwaak Adult abundance Smolt abundance Marine survival Juvenile salmon densities

3 Salmon Assessment Team for Inner and Outer Bay of Fundy Region Team includes 3 full time and 3 seasonal staff DFO reliance on partners to carry out all our conservation and assessment activities Our activities are well integrated with the two Biodiversity Facilities (Mactaquac and Coldbrook) Collecting juvenile salmon for conservation programs Pre-smolts on the Tobique for Captive-rearing (OBoF) Smolts on Big Salmon and Gaspereau rivers for the Live Gene Bank programs (IBoF)

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5 Life Cycle 2SW adult 3SW adult MSW adult 1SW adult Marine environment Immature (post-smolt) Smolt Spawning adult Kelt Alternate repeat Consecutive repeat Freshwater environment Eggs Alevins Age 0 fry Age 2+ parr Age 1 parr

6 Methods used to assess the various life stages of salmon Fry Parr Smolt Adult Salmon Eggs Electrofishing Smolt Wheels Fishway, Dive surveys and Counting Fence

7 Status of Atlantic salmon in OBoF Status of the river is based on the estimated egg deposition (= adult abundance and biological data) against a Reference Point referred to as the Conservation Egg Requirement (CER) The CER is based on an egg deposition rate of 2.4 eggs / m 2 of productive rearing habitat. Example: Above the counting fence on the Nashwaak there is 5.35 million m 2 of habitat therefore the CER= 12.8 million eggs. E.g. attained by 3,500 1SW and 1,350 MSW salmon.

8 Other indicators of population status for other life stages Juvenile Abundance - Electrofishing Surveys Elson Norms (Elson 1967) to maximize freshwater production Fry or age-0+ parr 29 fish per 100 m 2 Age-1+ and older parr 38 fish per 100 m 2 of habitat Smolt Abundance Smolt Wheel Operations 3.8 smolts per 100 m 2 of habitat (Symons 1979)

9 Monitoring sites OBoF & IBoF Regions Saint John River Above Mactaquac Dam Fish collection facilities at Mactaquac Dam Smolt wheel, electrofishing, fishway - Tobique River Nashwaak River Smolt wheel, electrofishing, counting fence Inner Bay of Fundy rivers Smolt wheel and adult snorkel surveys Big Salmon (NB) Bypass and fishway Gaspereau River (NS) Smolt wheel Stewiacke River (NS)

10 Nashwaak River - Counting Fence Index river for tributaries downstream of Mactaquac Dam Collaborative project with Oromocto and Kingsclear FN s 23rd season of operation

11 31-May 7-Jun 14-Jun 21-Jun 28-Jun 5-Jul 12-Jul 19-Jul 26-Jul 2-Aug 9-Aug 16-Aug 23-Aug 30-Aug 6-Sep 13-Sep 20-Sep 27-Sep 4-Oct 11-Oct 18-Oct 25-Oct 1-Nov Counts Discharge Nashwaak River - Counting Fence MSW 1SW Discharge m^ Operational from early June to mid/late October annually. 24 hr / 7 days a week operation Not a complete count because of high water events Mark (fence) and recapture (seining) project to estimate total returns

12 Photos of Nashwaak Assessment

13 Counting Fence Operation in 2015 In 2015, the counting fence was operated from May 28 until Sept. 30 by Kingsclear and Oromocto First Nations staff Counts were 197 1SW and 30 MSW salmon (only portion of total returns) There were 4 periods when fence was not fishing 100% due to high water 63% (20 of 32) salmon captured during seining (Sept 29) were Marked at fence. Preliminary estimated returns were 316 1SW and 48 MSW salmon. Adult abundance since Nashwaak

14 Egg Deposition against CER Use % and size of spawners -> estimate eggs Preliminary Estimate Nashwaak was only 5% of CER (12.8 million), 4 th consecutive year <10%.

15 Nashwaak River Smolt Project Partnership between DFO, Oromocto First Nation and Nashwaak Watershed Association ongoing since 1998 Smolt Wheels are borrowed from ASF and NB Salmon Council One or two smolt wheels operated from mid-april to late May Annual estimates of the smolt production are derived using Mark and Recap techniques Estimates provide the basis to determine freshwater and marine survival Collect data on smolt size, age distribution, run timing

16 Nashwaak Spring Smolt Assessment Two RSTs operated from May 3 to May 31 (2015) The smolt estimate in 2015 was 7,900 fish Third lowest smolt output since smolts/100 m 2 vs 3.8 for a healthy population

17 Nashwaak Smolt Smolt Size Mean fork length was among the highest largest in time-series is a function of the high proportion of age-3 smolts Age breakdown of 2015 smolts is reflected in spawner abundance age-3 (2011 spawners) age-2 (2012 spawners)

18 Nashwaak Smolt Run Timing Another late/cool spring so smolt emigrated later but not abnormally late Very similar to 2014

19 Index of Marine Survival Nashwaak - wild smolt Return Year 1SW 2SW yr mean Preliminary 2015 values: 1SW=2.8% 2SW=0.24% (not shown)

20 Nashwaak Pre-smolt Monitoring Project Goal: Investigate the low FW production (egg to smolt survival) observed within Nashwaak River (<1%, except 1 year) RST operated from Sept. 29 Nov. 12, 2014 Total Catch= 104 pre-smolts Population Estimate= 1,500 fish Majority of catch occurred between late Oct and mid-nov Magnitude of fall pre-smolt migration warrants future investigation Currently operating one RST again this fall with assistance from Oromocto First Nation

21 Juvenile Abundance Electrofishing Surveys Collaborative with Woodstock First Nation 7 index sites have been completed annually since 70 s

22 Electrofishing sites within Nashwaak Watershed Sites 1, 2, 3, 5, 8, 9, 10 are completed on an annual basis

23 Fry and Parr Abundance Juvenile densities have trended downwards over the past 4 decades. Mean parr densities at these 7 index sites has been fluctuating around 5 parr per 100m 2 of habitat which is below Elson norm.

24 Other data collected by DFO Water temperature recorders Main stem of the Nashwaak near counting fence and on the Tay River (tributary). Recording hourly temps during migration periods

25 Links to Publications and Counts DFO Status of Atlantic Salmon in Salmon Fishing Areas (SFAs) and 23. DFO Can. Sci. Advis. Sec. Sci. Resp. 2015/ RS/2015/2015_021-eng.html DFO website for bi-monthly Atlantic salmon counts

26 Acknowledgements Kingsclear, Oromocto and Woodstock First Nations Collaborators on all monitoring projects Nashwaak Watershed Association Inc. Volunteers assist on weekends spring smolt assessment Mactaquac Biodiversity Facility staff Transport and store assessment gear Atlantic Salmon Federation and NB Salmon Council Loan of RSTs for pre-smolt and smolt assessments