Ocean Conditions; plankton, marine food chains, salmon, hypoxia and climate change

Transcription

1 Ocean Conditions; plankton, marine food chains, salmon, hypoxia and climate change Bill Peterson Senior Scientist NOAA Fisheries Hatfield Marine Science Center Newport Oregon See Ocean Conditions and Salmon Forecasting

2 We Today are contributing I will speak to about salmon management by studying the Large ocean scale forces phase acting of their at the life history and by developing local each scale of can these influence aspects biological of management process ocean important advice conditions for based salmonon a suite of physical, biological and ecological indicators of ocean conditions 6 5 N A la s k a 6 PDO B ritis h C o lu m b ia Local Conditions Upwelling & SST Spring Transition Coastal currents ENSO U.S.A W This work is an example of an ecosystem approach to management, one based chiefly on active sea-going programs Local Biological Conditions: The Food Chain

3 Images of two types of plankton that play key roles in a salmon s food chain: copepods and krill, COPEPODS Omega-3 fatty acids KRILL

4 Outline Four events in the ocean have shaped salmon returns over the past 2 years: Poor returns in the 199s due to extended warm ocean conditions Spectacular (and historic) returns in early 2s A salmon disaster resulting from the 25 warm ocean event Another relatively spectacular recovery shortly thereafter Current Issues That I will Touch On (if there is time). What happened to the squid invasion of 28-29? What happened during the moderate El Niño of 21 How is this year (211) shaping up? Strong upwelling this year, A potential problem with hypoxia on the horizon

5 126 W 125 W 124 W 123 W Observations 48 N La Push 47 N 46 N 45 N Queets River Grays Harbor Willapa Bay Columbia River Cape Falcon Cape Meares Cascade Head Newport Cape Perpetua Washington Oregon ^_ Newport Line biweekly sampling since 1996 (16th year) Juvenile salmon sampling in June and September since 1998 (14th year) Historical data: hydrography, 196s; plankton, ; 1983, juvenile salmon,

6 Sampling methods Copepods with ½ m diameter 2 µm mesh net towed vertically from 1 m Krill with 7 cm 333 µm mesh Bongo net towed obliquely Salmon with pelagic rope trawl, Nordic 264 from NET Systems

7 SPRING COHO FALL

8 Yearling Coho Salmon Yearling Chinook Salmon Subyearling Chinook Salmon June September June September June September

9 Salmon Stock Groups: Total is all Fall ocean type Chinook SCG = Spring Creek Group; Snake = Snake River; UCR =upper Columbia River

10 Four physical factors affect plankton, food chains, pelagic fish and the growth and survival of salmon in the northern California Current Large-scale circulation patterns and the kinds of water that feed the California current Seasonal reversal of coastal currents: southward in summer northward in winter Coastal Upwelling Phase of the Pacific Decadal Oscillation (PDO) Everything is on the the web at: Ocean Conditions and Salmon Forecasting

11 Oceanography 11

12 Circulation off the Pacific Northwest Plankton are drifters, thus Subarctic Current brings cold water and northern species towards the N. California Current; The West Wind Drift brings subtropical water and subtropical species towards the N. California Current Therefore, ecosystem structure is affected by the source waters which feed the California Current.

13 Local winds drive currents and cause upwelling along the coasts of Washington, Oregon and California

14 CHART OF SEA SURFACE TEMPERATURE Note: warm water between the equator and ~ 3 N Because of upwelling off North America, S. America N. Africa and S. Africa, cool water is found at the coast. Without upwelling, the coasts would be ~ 5-1EC warmer during summer because offshore waters would move shoreward. Without upwelling we would have no salmon off PNW

15 Winds and current structure off coastal Oregon: Winter: - Winds from the South - Downwelling - Poleward-flowing Davidson Current - Subtropical and southern plankton species transported northward & onshore - Spring Transition in April/May Summer: - Strong winds from the North - Coastal upwelling - Equatorward alongshore transport - Boreal/northern species transported southward Fall Transition in October 46 N Winter: 45 N 44 N 43 N 42 N Summer: 46 N 45 N 44 N 43 N Newport Newport WA OR WA OR 42 N

16 The PDO has two phases, resulting from the direction from which winds blow in winter. PDO & SST The SST anomaly patterns shown on the right results from basin scale winds: W ly and NW ly [negative phase] and SW ly [positive phase] Westerlies dominated during winter 7-8; SW ly winter 9-1. Blue is anomalously cold Red is anomalously warm EOF Analysis produces a score which describes the SST pattern across the entire North Pacific

17 PDO Index (sum of May-Sept) PDO: May-Sep Average, Warm Regime Cool Regime Warm Regime C W C From , PDO shifted every 2-3 years between warm and cool regimes. However, we have had two shifts of four years duration recently: and 23-26, and another shift in late 27, thus we have a natural experiment to test the affects of PDO on marine food chains and salmon populations. Note 28: most negative PDO since 195s

18 Counts at Bonneville Dam Values: May-Sep Spring Chinook Fall Chinook Coho Salmon Pacific Decadal Oscillation YEAR Salmon returns since 199: counts at Bonneville Dam PDO in warm phase until 1998 & salmon had poor survival PDO phase shift in late 1998 followed by record returns Another phase shift in late 22 saw declining salmon stocks Yet another shift in 28 saw another round of enhanced returns

19 15 year time series of SST off Newport shows that PDO downscales to local SST PDO (colors) and MEI (line) Indices NOAA Buoy 465 Temperature Anomaly YEAR Temperature differences usually + 1 C PDO and SST correlated, (as they should be. Note the three recent periods of persistent sign changes: mid-1999, mid- 23 and mid-27 However there are time lags between PDO sign change and SST response of ~ 3-5 months, suggesting perhaps that the PDO is an advective signal along the Oregon coast

20 Deep water on the continental shelf is also different depending on the PDO: Temperature-Salinity at 5 m TEMPERATURE T-S Properties at 5 m depth at NH s average SALINITY ENSO: 83, 97, 98 Positive PDO: 3-6 Weak PDO: 9-1 Negative PDO: 99-2, 7-8,196s

21 PDO, MEI and Copepod Species Richness Anomaly PDO and MEI Copepod Species Richness Anomaly YEAR Warm Water Species Cold Water Species

22 PDO and zooplankton: copepod community composition As I suggested earlier, the sign of the PDO is associated with advection of either warm or cold water to the coast. PDO Values Copepod Community Composition Index PDO YEAR As a consequence you get warm and cold water zooplankton communities in coastal waters in association with positive or negative phase of the PDO. Warm water community Cold water community

23 Contrasting Communities Negative PDO = cold-water copepod species. These are dominants in Bering Sea, coastal GOA, coastal northern California Current Pseudocalanus mimus, Calanus marshallae, Acartia longiremis Positive PDO = warm-water copepods. These are common in the Southern California Current neritic and offshore NCC waters Clausocalanus spp., Ctenocalanus vanus, Paracalanus parvus, Mesocalanus tenuicornis, Calocalanus styliremis Based on Peterson and Keister (23)

24 Comparisons in size and chemical Warm-water taxa - (from offshore OR) are small in size and have minimal high energy wax ester lipid depots Cold-water taxa (boreal coastal species) are large and store highenergy wax esters as an over-wintering strategy composition Therefore, significantly different food chains may result from climate shifts;

25 Proportion of cold water species: (Pseudocalanus, Calanus marshallae and Acartia longiremis) showing seasonal cycle as well as differences between cold and warm phases of the PDO PROPORTION COLD WATER SPECIES YEAR

26 cold neritic warm neritic subarctic (cold) oceanic warm oceanic Proportion of Total Copepod Biomass Proportion of copepod community types in zooplankton tows from Newport Line Station NH Year

27 A working mechanistic hypothesis: source waters... Cool Phase Cool Phase Transport of boreal coastal copepods into NCC from Gulf of Alaska Warm Phase Transport of subtropical copepods into NCC from Transition Zone offshore Warm Phase Verified in Keister et al. 211 GCB and Bi et al. 211 GRL

28 Salmon Habitat and Forecasting In order to forecast returns of various salmon life history types, and to better understand interannual variaiblity, we must first establish where they live in the ocean. As shown earlier, we have done this from our surveys in May, June and September since 1998 and have established that they are found only on continental shelf waters

29 Forecasting - since we know that juvenile salmon live in continental shelf waters, we use indices relevant to shelf waters and as I said earlier, we must also consider forces acting from great distances Basin scale indicators PDO MEI Local indicators SST Upwelling Date of spring transition Length of upwelling season Biological indicators Copepod biodiversity N. copepod biomass anomaly Biological Spring Transition Copepod Community Structure Fish larvae collected in winter Catches of spring Chinook in June Catches of coho in September

30 Catches of juv. Salmon in trawl surveys Number per km towed June September Black bars = coho Red bars = spring Chinook Sept 21 among the lowest catches of coho (rank 11/13) June 21 among the highest catches spring Chinook (rank 5/13) Number per km towed

31 Basin Scale Physical Indicators PDO MEI Negative is good Negative is good Local Physical Indicators SST Date of spring transition Length of upwelling season Deep water temperature Cold is good Early is good Long is good Cold is good Local Biological Indicators Copepod species richness Northern copepod biomass Winter fish larvae Low is good High is good High is good Catches of juvenile salmon on surveys Chinook catches in June Coho catches in September High is good High is good

32 Indicator Values PDO (December-March) PDO (Sum May-September) MEI Annual MEI Jan-June SST 465 deg C SST NH 5 Summer deg C SST NH 5 Winter Befor deg C SST NH 5 Winter After Edeg C Physical Spring Trans U Day of Year Upwelling Anomaly (April-May) Length of upwelling sea days NH 5 Deep T deg C NH 5 Deep S Copepod richness anomno. of spec Northern Copepod Biomlog biomas Biological Transition Day of Year Copepod Community strx-axis ordin Winter Ichthyoplankton log biomas June-Chinook Catches fish per km Sept-Coho Catches fish per km

33 1998, = warm & unproductive; poor salmon returns and 28 = cold & productive; record returns 21 = a mixed bag poor early, great late! Environmental Variables PDO (December-March) PDO (May-September) MEI Annual MEI Jan-June SST at 465 (May-Sept) SST at NH 5 (May-Sept) SST winter before (Nov-Mar) Physical Spring Trans (UI Based) Upwelling Anomaly (Apr-May) Length of upwelling season (UI Bas Deep Temperature at NH Deep Salinity at NH Copepod Richness Anomaly N.Copepod Anomaly Biological Transition Copepod Community structure Winter Ichthyoplankton Catches of salmon in surveys June-Chinook Catches Sept-Coho Catches Mean of Ranks of Environmental Da RANK of the mean rank

34 C o u n ts o f A d u lt S a lm o n a t B o n n e v ille D a m X D a ta S p rin g C h in o o k R -sq =.57, p = X D a ta F a ll C h in o o k R -sq =.52, p = C o h o R -sq =.51, p =.8 28 and 29 Ocean Entry Salmon counts at Bonneville Dam vs. mean rank of all variables. Arrows indicate forecast for 21: Spring Chinook (28 ocean entry): 278K returned in 21, forecast was ~ 35K Fall Chinook (28 ocean entry): 467K returned in 21; forecast was ~ 55K. Of the coho that went to sea in 29, 121K returned in 21; forecast was 11K. Of the coho that went to sea in 28, 225 K; forecast was 21K R a n k o f th e M e a n R a n k s

35 Copepod data alone fit the counts at Bonneville fairly well OPIH Coho Survival (%) y = e.574 x R-sq =.2 p =.1 R-sq =.58 if 7, 73 deleted N. Copepod Biomass Anomaly Number of Fall Chinook Adults returning to Columbia River to spawn R-sq = Northern Copepod Biomass Anomaly (log) OPIH - Coho Survival (%) R-sq =.24; p = Boreal Community Sub-Tropical Community Copepod Community Structure Index Number of adult fall Chinook salmon returning to the Columbia River to spawn R-sq = Copepod Community Structure X-Axis Ordination Scores

36 Returns Returns Returns 2e+5 3e+5 4e+5 5e+5 6e MCA Score 28 prediction: r^2 = Spring Chinook Salmon New Goal: to develop quantitative relationships between the suite of indicators and adult returns MCA Expansion Coefficient prediction:.45 2 r^2 =.67 Using Maximum Covariance and partial least squares Analysis MCA Expansion Coefficient prediction: Coho Salmon Fall Chinook Salmon Spring Chinook returns in 21: Bonneville Dam Count was 278K MCA Index Prediction: 289, Peterson: ~ 35 K r^2 =

37 21 Ocean Entry Salmon counts at Bonneville vs. mean rank of environmental variables Expect 15, spring Chinook in spring 212 Expect ~ 31, fall Chinook in fall 212 Expect ~ 1, coho in fall 211 Expect ~ 2.6% OPIH

38 Spring Chinook at mouth of Columbia 5 4 U s (y) v s T A C (x ) F Is h to th e m o u th o f th e C o lu m b ia R iv e r TAC Actual from the TAC P E T E R S O N T A C a c tu a l Peterson data from the composite index (mean rank from stoplight chart) R 2 =.64

39 Even you can make a forecast. Just check our webpage Phase of the PDO Upwelling Cold water coming from northern BC coast Cold water lipid-rich zooplankton, krill and small fish Ocean Conditions and Salmon Forecasting

40 A chain of events (in a perfect year) Changes in basin-scale winds lead to sign changes in PDO SST changes as do water types off Oregon Spring transition Upwelling season Zooplankton species Food Chain Forage Fish Juvenile salmonids Negative Cold/salty Positive Warm/fresh Early Late Long Short Cold species Warm species Lipid-rich Lipid-deplete Many Few Many Few But time lags between PDO changes can complicate interpretations as do pesky El Niño events

41 What about climate change? Climate is what you expect; weather is what you get! Climate change means that the weather (and the ocean) will change but in ways that we may not expect!

42 The surprises: the unanticipated events Ocean acidification (now less of a surprise) Waters of low oxygen content are shoaling in CC Summer of 25 no upwelling until mid-july Fish Kills in 26 + nearly anoxic waters on Heceta Bank Humboldt squid appeared in large numbers in Collapse of Sacramento River fall Chinook salmon runs in 27, 28 and 29 but record runs to the Columbia River Record runs of steelhead recently. Massive bloom of the dinoflagellate Akashiwo sanguinea, a first (!) resulting in deaths of large numbers of seabirds off the coast of Washington Mola mola, ocean sunfish, extremely common in September 29 21: a moderate El Niño event that proved strong 211: negative PDO and fairly strong upwelling

43 What problems lie ahead for salmon and other fishes off the Pacific Northwest? Will coastal upwelling become weaker, stronger or stay the same? Will warming of the ocean lead to greater stratification thus reducing the effectiveness of coastal upwelling? Will the Pacific Decadal Oscillation return to Decadal? Will the central North Pacific Gyre expand northward and make the waters off Oregon more subtropical? Alternatively, will expansion of the gyre make coastal upwelling more productive? Of great concern in coastal upwelling systems is the trend toward decreased oxygen concentration and of decreased ph in waters which upwell at the coast.

44 Two Contrasting Years 25. The year that resulted in collapse of the Sacramento Fall Chinook run. 28. The year that resulted in near-record returns of spring and fall Chinook, coho, steelhead and sockeye to the Columbia and other rivers of the Pacific Northwest.

45 25

46 28

47 Humboldt Squid: Changes in marine food chains Photo taken just outside Ucluelet near Tofino BC Published in <

48 Oxygen in shelf waters off Newport Oxygen concentration (ml L -1 ) Oxygen concentration at 5 m depth at NH 5 (station depth = 62 m) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Month of the Year Jun 31 Oct ~ 13 d Jun- 12 Sep ~ 9 d Jun 5 Aug ~ 45 d 29 8 Jul- 27 Aug ~ 5 d 21 3 Sep - 9 Sep ~ 7 d Jun- ~ 8 d (at least)

49 Oxygen data from CTD casts during the September Juv. Salmon trawl survey:26-21 September 21-28, 21 September 22-28, 27 September 23 - October 1, 28 September 22-29, 29 September 2-28, 26 Minimum Oxygen Values (ml/l) Minimum Oxygen Values (ml/l)minimum Oxygen Values (ml/l) Minimum Oxygen Values (ml/l) Minimum Oxygen Values (ml/l) Washington48 N 48 N Washington Washington48 N 6 LaPush LaPush N N LaPush N Washington 48 N LaPush Washington 48 N LaPush 47 N 3 47 N 1 Astoria 46 N 46 N 46 N Oregon Astoria Astoria Astoria 46 N Astoria 46 N Oregon Oregon Oregon Oregon Tillamook Tillamook Tillamook Tillamook Tillamook 45 N 45 N 45 N 45 N 45 N Newport 124 W 123 W 125 W 124 W Newport Newport Newport 125 W 123 W 125 W 124 W 123 W 125 W 124 W Newport 123 W 125 W 124 W Widespread hypoxia (blue/purple color) in 26 and 27; Virtually none anywhere in W

50 21 was a confusing year My yard in Newport was overrun by Townsend s chipmunks in 21 (live trapping dealt with that as bait, they seemed to prefer cantaloupe over grapes) My cherry tomatoes did not ripen until October Our wild blackberries never ripened!

51 Where is our work headed? Expanded surveys of salmon with Southwest Center and of hydrography and plankton with NOAA ships Copepod indicators along (Workshop last week in Newport)

52 Coast-wide Surveys: Scope 48 N 47 N Queets Washington 46 N An annual coast-wide survey, supported by NOAA ships? Gather physical and biological data from the Canadian border south to Monterey Each year: 3, 3-day cruises (Feb-March, May, June, and September) 45 N 44 N 43 N 42 N 41 N 4 N Newport FishingTransects (Juvenile salmon, phys & biol metrics) Sampled June-July, Sept-Oct Hydrographic Lines (Physical Oceanography & zooplankton) Sampled biweekly to monthly Trinidad Head Oregon California Establish/maintain long term biweekly-monthly observations of ocean conditions (partly with contract vessels) along 4 lines 39 N Bodega Bay 38 N 37 N Kilometers 36 N 129 W 128 W 127 W 126 W 125 W 124 W 123 W 122 W 121 W

53 Acknowledgements Bonneville Power Administration U.S.GLOBEC Program (NOAA/NSF) NOAA Stock Assessment Improvement Program (SAIP) Fisheries and the Environment (FATE-NOAA) National Science Foundation Office of Naval Research NASA See Ocean Conditions and Salmon Forecasting

54 Summary: 21 had to be a confusing year from the viewpoint of a salmon (red=bad; green = good): PDO strongly positive in winter (El Niño) then strongly negative in summer (La Niña), similar to MEI. SST warm early; cold late Spring transition early (~day 9) but significant upwelling did not begin until two months later, on ~ day 16 Barely a hint of hypoxia Copepod species richness high throughout spring/summer/fall; Northern copepod biomass low in spring but very high in summer; Fish larvae in winter (this is a new index) very abundant (rank 3/13) suggesting good feeding for juv. Salmon when they enter the ocean in May Fairly high catches of spring Chinook in May & June but really lousy catches of coho in September;

55 SST Anomalies at the NOAA Buoy 465: SST in summer 21 similar to 28, however the winter of 28 was very cold (with few storms) whereas winter 21 was warm due to many SWly storms SST Anomaly (deg C) SST Anomaly (deg C) -6 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec No data: Jan-Feb 21 due to sensor failure

56 PFEL Cumulative Upwelling Index 45 N Cumulative Value of the Upwelling Index Cumulative Upwelling at 45 N Climatology strong upwelling no winter storms but not much upwelling either 21. Intense winter storms; summer similar to Day of the Year Climatology is the red dotted line

57 Salmon have a patchy distribution

58 Fall (subyearling) ocean-type Chinook salmon

59 Pteropod Time Series (Limacina helicina) Number per m Limacina: , 1983, Number per cubic meter 12 NH Year Year

60 12 NH 5 Number per cubic meter Year NH 25 Limacina NH 5 = 62 m NH 25 = 3 m NH 65 = 3 m Year NH Year

61 Seasonal cycle of upwelling and temperature and salinity Temperature at 5 m ( o C ) U I 4 5 N Salinity at 5 m YEAR YEAR

62 Axis 2 369NH NMDS (Non-Metric Multidimensional Scaling) Plot of Copepod Community Structure NH5Copedensall_norare5_log1_nooutstns3SD_NMS 2. Year NH 1149NH 3249NH Axis 1 X-axis explains about 7% of the variance

63 Interannual Variability in Copepod Community Structure 2.5 N H - 5 C o p e p o d C o m m u n ity S tru c tu re : x -a x is o rd in a tio n s c o re s m o n th ly a v e ra g e d b y y e a r X -a x is s c o re s YEAR Positive scores = warm water community; usually in winter Negative scores = cold water community; usually in summer Exceptions: El Nino 1998 and summer 25