Habitat and Ecology of Large Medusa in the Northern California Current: An Overview of Recent Studies

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1 Habitat and Ecology of Large Medusa in the Northern California Current: An Overview of Recent Studies Richard Brodeur NOAA Fisheries, Newport, OR Cynthia Suchman Virginia Sea Grant, UVA Elizabeth Daly and Lanaya Fitzgerald HMSC, OSU, Newport, OR

2 Sampling Locations 128 W 127 W 126 W 125 W 124 W 123 W 122 W 121 W 49 N 49 N Latitude 48 N 48 N 47 N 47 N 46 N 45 N 46 N 44 N La Push Queets River Grays Harbor Willapa Bay Columbia River Cape Meares 45 N Cascade Head 43 N 42 N U.S.-Vancouver Columbia Eureka Triennial Survey ( ) Newport Plume Survey ( ) LaPush GLOBEC Survey (2000, 2002) Predator Survey ( ) La Push Washington 200 m 100 m Grays Harbor Astoria Oregon Tillamook Newport Willapa Bay Oregon Canada Washington Astoria Columbia River Newport Coos Bay Cape Blanco 125 W 124 WCrescent City 123 W California 48 N 47 N 46 N 45 N 44 N 43 N 42 N 128 W 127 W 126 W 125 W 124 W 123 W 122 W 121 W Longitude

3 Sampling Methods 127 0'0"W 126 0'0"W Tatoosh Island (TI) Father and Son (FS) 48 0'0"N La Push (LP) 125 0'0"W '0"W 123 0'0"W 4 Queets River (QR) '0"N Grays Harbor (GH) Willapa Bay (WB) depth 18 m 46 0'0"N Columbia River (CR) Cape Falcon (CF) Mesoscale 10-day cruises (trawls=1102): May, June, Sept cross-shelf transects (1-40 nm from shore) surface trawls, CTD, zooplankton tow, chl a 45 0'0"N Cape Meares (CM) Cascade Head (CH) Newport Hydro Line (NH) Cape Perpetua (CP) 126 0'0"W 125 0'0"W 124 0'0"W Station Location Current 100 Fathom Regular 100 fathom/ end Discontinued Regular 100 Fathom 123 0'0"W 4 Biweekly 2-night cruises (trawls=882): April-August cross-shelf transects (Columbia River and Willapa Bay) surface trawls and CTD

4 Vertical Distribution from ROV Surveys Chrysaora fuscescens: Depth Distributions DIVE 199 off Central Oregon August 7, n=11 Temperature ( o C) Oxygen (ml/l) DEPTH (m) TEMPERATURE DENSITY OXYGEN 50 Water Density Medusae Prop Phantom ROV

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6 Catch Summary: Mesoscale Cruises Medusa FO (%±sd) # /km -2 (±sd) Max (per 1000 m 3 ) C. fuscescens 42 ± ± (Sept 2000)* Aequorea sp. 40 ± ± (June 2002) Aurelia labiata 19 ± ± (June 2004) Phacellophora/ 10 ± 11 2 ± (June 2002) Cyanea All medusae 66 ± 19 * Twice the maximum caught in previous surveys off Central OR, August 2000 (Suchman and Brodeur DSR 2005); approx 120 mg C/m 3

7 Seasonal Patterns Chrysaora fuscescens Abundance by Month, April May June July August Sept 0 Aequorea sp. Abundance by Month, April May June July August Sept Chrysaora per 1000 m 3 Aequorea per 1000 m 3 0

8 Length Distributions by Month

9 General Additive Modeling of Environmental Variables Chrysaora fuscescens Deviance explained:47.7% Significant: latitude (+/-) temperature (-) distance (-) salinity (-) 48 N 47 N 46 N September 2001 LaPush Washington Astoria Oregon Chryaora fuscescens 0 to to to to to to to N 47 N 46 N September to to to to 1000 LaPush 1000 to 5000 Washington Astoria Chryaora fuscescens Oregon Tillamook Tillamook 45 N 45 N Newport Newport 125 W 124 W 123 W 125 W 124 W 123 W

10 General Additive Modeling of Environmental Variables Aequorea sp.: Deviance explained: = 33.6% Significant: latitude (+) chlorophyll (+) salinity (+) distance (-) 48 N 47 N 46 N 45 N June 2001 Aequorea sp. 0 to to to 500 LaPush Washington Astoria Oregon Tillamook 48 N 47 N 46 N 45 N June 2004 Aequorea sp. 0 to to to 500 LaPush 500 to 1000 Washington Astoria Oregon Tillamook Newport Newport 125 W 124 W 123 W 125 W 124 W 123 W

11 Correlation with Climate: Pacific Decadal Oscillation Jellyfish Anomaly (km -1 ) PDO anomaly PDO Anomaly (May-Aug) average per km towed March-September PDO Anomaly by Month and Year Jellyfish Catch cold warm Pacific Decadal Oscillation (May-August) Jellyfish Catch # jellyfish per total km towed PDO (May-August) and jellyfish per km towed 2008 r 2 = PDO (Suchman et al. In prep.)

12 Correlation with Columbia River Flow Streamflow Anomaly (cubic feet) 6e+5 4e+5 2e+5 0-2e+5-4e+5-6e+5-8e+5 discharge ft 3 /s Columbia River Flow Columbia River Streamflow (Jan.-August) USGS, Columbia River at Beaver Army Terminal # Jellyfish per total Km towed River flow (Jan-Aug.) and Jellyfish per km towed 2001 r 2 = River flow (million cubic feet) (Suchman et al. In prep.)

13 Multiple Linear Regression catch/km = ( * annual flow ft 3 /s) - (9.86 * summer PDO anomaly) r 2 adj = p < R 2 adjusted p=0.01 p<0.001 r 2 adj = p = # Jellyfish per km towed # Jellyfish per km towed River flow (10 6 ft 3 ) River flow (10 6 ft 3 ) PDO PDO 2 4

14 Interactions with Fish? Total number caught in August 2002 Large Medusae: 17,937 Pacific herring, sardine, anchovies: 9,997 All other fishes (34 species): 1,923

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16 Summary Chrysaora fuscescens dominated the biomass Mesoscale distribution characterized largely by latitude, depth, chlorophyll and salinity highest abundances along inner shelf Annual abundance of large medusae in the region correlates (negatively) with spring-summer PDO (SST anomalies) and Columbia River flow Contrary to hypothesis of warm conditions leading to jelly blooms

17 Acknowledgements Bonneville Power Administration National Research Council U.S. GLOBEC Program (NOAA/NSF) NOAA Fisheries Cheryl Morgan, Jim Ruzicka (OSU) Ed Casillas, Bob Emmett (NOAA NWFSC) Bill Miller, Dave Fox (ODFW) Captains and crew of FV Frosti, FV Sea Eagle, RV Miller Freeman, RV Ricker, and the many seagoing scientists participating in the fieldwork component of this project

18 Can Jellyfish Blooms Have an Impact on Pelagic Fishes? 1. Do pelagic fish and jellies have similar diets? 2. Do they overlap in distribution?

19 Pelagic Fishes Examined Pacific herring (Clupea pallasi) Jack mackerel (Trachurus symmetricus) Pacific saury (Cololabis saira) Pacific sardine (Sardinops sagax) Northern anchovy (Engraulis mordax) Juvenile coho (Oncorhynchus kisutch) Surf smelt (Hypomesus pretiosus) Whitebait smelt (Allosmerus elongatus) Juvenile chinook (O. tshawytscha)

20 Comparison of Fish and Jellyfish Diets: August 2002 Sardinops sagax, Pacific sardine 49 fish, mean length = 234 mm 52,200 prey Chrysaora fuscescens, Sea nettle 17 medusae 26,040 prey 73.8% Aurelia labiata, Moon Jelly 11 medusae 8055 prey calanoid copepods euphausiid eggs euphausiid nauplii-calyptopes larvaceans pteropods other 72.8%

21 Major Prey by Species Chinook yearling Coho yearling Chinook subyearling Surf smelt Gelatinous zooplankton Larvacean Pteropod Calanoid copepod Euphausiid eggs Euphausiid (naup.-calypt.) Euphausiid (furcilia-adults) Osteicthyes (egg-juvenile) Other N = 10 Jack mackerel Chrysaora N = 31 N = 33 Aurelia N = 59 Pacific sardine N = 160 Whitebait smelt N = 17 N = 11 N = 49 Northern anchovy Pacific saury Pacific herring N = 41 N = 63 N = 114 N = 145 (Brodeur et al., Mar. Biol.)

22 Spatial Overlap with Sardines percent catch: Aurelia labiata 0.01 to < to < to < N 44 N June2002 August 2002 OREGON Chrysaora fuscescens 0.01 to < to < to < N Cape Blanco Sardinops sagax 0.01 to < to < to < N CALIFORNIA 125 W 124 W 125 W 124 W sardines vs Chrysaora: sardines vs. Aurelia: < 1 < 1

23 Index of Potential Overlap of Nekton with Jellyfish Nekton Chrysaora Aurelia Juvenile Chinook salmon Juvenile coho salmon Jack mackerel Whitebait smelt Surf smelt Pacific herring Pacific saury Northern anchovy Pacific sardine (Brodeur et al., Mar. Biol.)

24 Biomass of Pelagic Fish vs. Jellyfish Chysaora fuscescens Small forage Pelagic fishes Fishes spring summer spring summer Chrysaora fuscescens (Ruzick et al CalCOFI Rep.)

25 Biomass of Pelagic Fish vs. Jellyfish Tons/km Spring Washington/Columbia River All jellyfish Pelagic fish Fish:Jellyfish = 1.86 Tons/km Spring Northern Oregon All jellyfish Pelagic fish Tons/km 2 10 Summer Summer Tons/km

26 ECOPATH Ecosystem Model - Spring (Ruzicka et al CalCOFI Rep.)

27 Estimated Food Consumption during Different Seasons Spring model model (April-June) (April June) (July Sept.) large jellyfishes cephalopods forage fishes juvenile salmon juvenile rockfishes juvenile fishes (misc.) salmon pelagic (adult) piscivores mesopelagic fishes demersal fishes flatfishes rockfishes seabi rdsmammals Summer model (July-Sept.) large jellyfishes cephalopods forage fishes juvenile salmon juvenile rockfishes juvenile fishes (misc.) salmon (adult) pelagic piscivores mesopelagic fishes demersal fishes (misc) flatfishes rockfishes seabirds mammals (Ruzicka et al CalCOFI Rep.)

28 Conclusions In spring, jellyfish are a modest consumer of zooplankton production and small pelagic forage fishes are much more important consumers. By late summer, however, jellyfish are the major consumers of zooplankton.

29 Conclusions As they are preyed upon by few species, jellyfish become an important pathway that diverts lower trophic level production away from upper trophic levels. In summer < 1% of consumption of large jellyfish is passed on to higher trophic levels while > 20% of the energy consumed by forage fish is passed upwards.