Harmful Algae and Phycotoxins in San Francisco Bay: Assessing condition and exploring controlling factors Contributors to this Work: SFEI: Z Sylvester, M McKibben, T Winchell, E King, A Malkassian, P Trowbridge, D Senn

USGS: J Cloern, T Schraga, C Martin, E Nejad

UCSC: R Kudela, M Peacock, K Hayashi

Funding: - SFB Nutrient Management Strategy - SFB Regional Monitoring Program - USGS in-kind support Summer 2015 Domoic Acid (Amnesic Shellfish Poisoning)

Pseudo-nitzchia

NOAA Climate/NOAA View

• Domoic Acid in mussels harvested from Central Bay

• Apr-Sep 2015

• Modest increase, but well- below concerning levels for human health

Peacock et al 2018 • N and P loads place SFB in upper ~90%ile of estuaries worldwide (g m-2 d-1) Cloern et al., in prep

• N Concentrations throughout SFB exceed those in recently upwelled coastal water.

Delta/Ag NMS Overarching Management Questions Bay-wide Loads • What nutrient loads can SFB N: 50,000 kg d-1 (subembayments) assimilate without P: 5,000kg d-1 adverse impacts? 65% WWTP

20% Delta/Ag • What management actions would be 15% Stormwater effective at achieving protective nutrient loads or concentrations? HABs and PhycoToxins in SFB: Science/Management Questions

1. Water Quality / Habitat Quality: Substantial HABs // phycotoxin threat ? a. Sensitive population(s): Biota? Humans? b. Current vs. Future Conditions? 횫 Physical forcings → 횫 HA+phycotoxin severity? HABs and PhycoToxins in SFB: Science/Management Questions

1. Water Quality / Habitat Quality: Substantial HABs // phycotoxin threat ? a. Sensitive population(s): Biota? Humans? b. Current vs. Future Conditions? 횫 Physical forcings → 횫 HA+phycotoxin severity?

2. What factors regulate HA abundance and toxicity in SFB? transport, in situ production

3. Role of SFB nutrients: N,P → frequency or severity of HA events?

4. Protective nutrient loads, with respect to HAs and phycotoxins?

- Light availability - Temperature - Salinity - Mixing - Nutrients San Francisco Bay Delta

Lakes, Creeks, Urban runoff Marine ? Restored Salt Ponds Example Harmful Algal Bloom (HAB) forming species and toxins Domoic Acid (Amnesic Shellfish Poisoning)

Pseudo-nitzschia spp.

Microcystin toxins When are toxins produced? (hepatotoxin) When they are stressed…e.g.,

• Salinity, Temperature Microcystis spp.

• Nutrients (e.g., ± P, - Si, ±N) Saxitoxin • Light conditions (Paralytic Shellfish Poisoning)

Alexandrium spp. NMS Observation and Forecasting Program

What data and tools do we need to inform management decisions? Ship-based monitoring, with USGS NMS Observation and Forecasting Program

R/V Peterson Ship-based monitoring, with USGS NMS Observation and Forecasting Program Mussels

Phytoplankton: Microscopy, Sequencing (qPCR)

Algal toxin measurements

- Naturally occurring mussels

- Floating docks, readily-accessible

- Bi-weekly sampling (Sep 2015-present)

Collaborators: J Cloern (USGS), - Domoic Acid, Saxitoxin, Microcystin R Kudela (UCSC), T Otten (Bend Genetics) •MusselMultiple Toxin phycotoxinsconcentrations, regularly 9/2015- 3/2018detected in biota Lighter color, [tox] < LOQ – Domoic Acid Low Grey = [tox] < LOD – Microcystin Moderate/Elevated – Saxitoxin Low/Moderate/Elevated – Okadaic Acid Moderate/Elevated • Regularly detect phycotoxins in water (particulate, dissolved) • Regularly detect multiple HA taxa

Saxitoxin (ppb) (800ppb) 1000

100

10

2016 2017 2018

1000 Domoic Acid (20,000ppb)

100

10

1

2016 2017 2018

Microcystin (10ppb) 10

1

0.1

0.01

2016 2017 2018 What can we learn, mechanistically, about HAs in SFB using long-term data?

- source? Example Harmful Algae Detections (SFB)

Density - internal growth? Karlodinium (cells/mL) - resident population(s)? Karenia Dinophysis - Predictors? Pseudo-nitzschia

Alexandrium

Sutula et al 2017 Develop and ‘Test’ conceptual models

H0 Delta A C Suisun B

H0 cells/mL C Central A time

Factor 1 H0 B

LSB Factor 2 indicator(s) of favorable Frequency or growth conditions abundance of HA time Dates/Locations of Phytoplankton Taxonomy

Karenia Heterosigma Dinophysis Noctiluca Karlodinium Gonyaulax Pseudo-nitzchia Alexandrium Prorocentrum Heterocapsa Alexandrium Prorocentrum Heterocapsa Alexandrium Densities (cells/mL) Prorocentrum Heterocapsa Alexandrium Densities (cells/mL) Prorocentrum Heterocapsa Alexandrium Prorocentrum Heterocapsa Amplicon Sequencing Pilot Project 80%

90%

75%

75%

50%

30%

Change in taxonomist What can we learn, mechanistically, about HAs in SFB using long-term data?

- source? Example Harmful Algae Detections (SFB)

Density - internal growth? Karlodinium (cells/mL) - resident population(s)? Karenia Dinophysis - Predictors? Pseudo-nitzschia

Alexandrium

Sutula et al 2017 Develop and ‘Test’ conceptual models

H0 Delta A C Suisun B

H0 cells/mL C Central A time

Factor 1 H0 B

LSB Factor 2 indicator(s) of favorable Frequency or growth conditions abundance of HA time How do HA detections and abundances vary relative to ‘bloom’ and. ‘non-bloom’ conditions? How do HA detections and abundances vary relative to ‘bloom’ and. ‘non-bloom’ conditions?

Thalassiosira – a healthy diatom

Dissolved Oxygen (%saturation)

Detect

Upper 25%ile abundance

nonDetect Alexandrium Pseudo-nitzchia

Karlodinium Dinophysis What can we learn, mechanistically, about HAs in SFB using long-term data?

- source? Example Harmful Algae Detections (SFB)

Density - internal growth? Karlodinium (cells/mL) - resident population(s)? Karenia Dinophysis - Predictors? Pseudo-nitzschia

Alexandrium

Sutula et al 2017 Develop and ‘Test’ conceptual models

H0 Delta A C Suisun B

H0 cells/mL C Central A time

Factor 1 H0 B

LSB Factor 2 indicator(s) of favorable Frequency or growth conditions abundance of HA time HA detection Frequency: Informative Spatial Patterns

Healthy diatom...

Pseudo-nitzschia Dinophysis Alexandrium Karlodinium Karenia Thalassiosira

Frequency Detected (%) Alexandrium: Frequency of Detection: Seasonally x Spatially Summary • SFB Nutrient concentrations are sufficiently high that adverse impacts could occur -- if a larger proportion of the nutrients were utilized. – Large phytoplankton blooms and low DO – Large-scale HAB events

• NMS is targeting highest priority science needs to inform management decisions

• HAB-forming species are commonly detected throughout the Bay. Multiple HAB-toxins have been regularly detected in water and biota.

• Challenging issues, but highly relevant to management decisions: – Sources of HAs and toxin – In situ growth vs. transport, and role of SFB nutrients – Identifying protective nutrient – Evaluating risks of “events” – present, future