Prymnesium parvum Documented in 1920s and 1930s in Europe Prymnesium - PDF document

5/25/2010 Prymnesium parvum • Documented in 1920s and 1930s in Europe Prymnesium parvum in Inland Waters • Flagellated • Mixotrophic • “feeding swarms” Photo: John LaClaire, University of Texas at Austin • Euryhaline Bryan W. Brooks 1 , James P. Grover 2 , Daniel L. Roelke 3 • Eurythermal 1 Baylor University, 2 University of Texas Arlington, 3 Texas A&M University • Encysts Bryan_Brooks@Baylor.edu; Tel: 254-710-6553 • Produces exotoxins – prymnesin ‐ 1, ‐ 2; others? – See Manning & La Claire (2010) for Photo: Christina Esplund, Edna Graneli prymnesin review 1 ORSANCO, 4 May, Cincinnati 2 Prymnesium parvum Blooms Lake • Originally a marine, coastal Possum Kingdom species • Moved inland to Texas Lake – Low salinities Granbury L k Lake – Invasive species Whitney – 1 st identified in Pecos River 1985 – Now identified in at least 5 river Lake basins, 33 water bodies Waco – 2 hatcheries affected States where golden algae identified 3 4 Prymnesium parvum Blooms Prymnesium parvum Blooms 5 6 1

5/25/2010 Towards a Predictive Understanding of P. parvum Lab Field Cell Density Does Not Always Correlate with Ambient Toxicity Toxicity believed to result following exposure to prymnesium ‐ 1, ‐ 2 and potentially others Ceriodaphnia dubia ‐ cosms Societal Value + ‐ Statistical Power + ‐ Variability ‐ + Igarashi et al 1999 7 8 Cell Density Does Not Always Correlate with Ambient Toxicity Previous Literature on P. parvum “Toxicity” Toxicity believed to result following Lack of analytical standards preclude ‐ Reviewed 96 published studies of aquatic toxicity attributed to in ‐ depth understanding of exposure, exposure to prymnesium ‐ 1, ‐ 2 and toxicology to aquatic and terrestrial P. parvum potentially others organisms, including mammals. ‐ 23.3% vertebrates, 21.1% zooplankton, 20% erythrocytes, ‐ 23 3% vertebrates 21 1% zooplankton 20% erythrocytes 1. Magnitude of toxins produced as a 1 M it d f t i d d 18.9% phytoplankton, 9.5% misc in vitro, 7.4% bacteria function of ecophysiology/stress? 2. Fate of various toxins under a ‐ Only 50.5% specifically reported salinity of the assay (10 studies range of environmental conditions: reported % of “seawater,” but not seawater salinity) photolysis, biotransformation? 3. Accumulation and higher trophic ‐ 14.7% studied salinities less than 4 psu; 11.6% of these studies level effects (maitotoxin)? were recently reported from our project team Igarashi et al 1999 9 10 Brooks et al 2010 Cell Density Does Not Always Correlate with Ambient Toxicity Abiotic Influences on Ambient Toxicity Optimum Conditions for Growth: ‐ temperature = 27 o C ‐ salinity = 22 psu Non ‐ optimum growth conditions = ↑ toxicity per cell (toxin production) Lower temperatures and low salinities = a recipe for Texas fish kills? Baker et al 2007 Granéli and Salomon 2010 11 12 2

5/25/2010 TAMU, UTA, BU Comparative Toxicity during a Limnocorral Study + P. parvum ‐ BSE + Nutrient Limitation and P parvum Nutrient Limitation and P. parvum ‐ ‐ 28 day study in Spring 2006 ‐ 2 3 factorial design (3 reps) � 1 m x 2 m limnocorals 13 14 Roelke et al 2007 TAMU, UTA, BU TAMU, UTA, BU Nutrient Treatment Main Effects Nutrient Treatment Main Effects melas Survival 16 35 * na Fecundity * 14 30 dilution) male-1) 12 25 Mean Pimephales prom 10 Mean Daphnia magn NOEC (percent (neonates fem 20 8 15 6 10 Less Toxic 4 Less Toxic More Toxic 5 2 More Toxic 0 0 No Nutrients Nutrients No Nutrients Nutrients 15 16 Roelke et al 2007 Roelke et al 2007 Roelke et al 2007 Comparative Aquatic Toxicity of P. parvum Nutrient Limitation Increases Toxicity Johansson and Granéli 1999 Valenti et al 2010 17 18 Brooks et al 2010 3

5/25/2010 Heterogeneity of bloom: High ‐ resolution mapping TAMU Dataflow On ‐ board, flow through system with geo ‐ referenced data collection Hydrology Salinity and P parvum Hydrology, Salinity and P. parvum 19 20 Hydraulic flushing terminates a toxic bloom in Lake Granbury, Brazos River, Texas 120 River flow (10 6 m 3 d -1 ) 0 Lake Granbury Chlorophyll- a Following prolonged (µg liter -1 ) period of drought period of drought Chlorophyll a patches on the scale of 1 km ‐ Bloom initiation prior to Feb. 2007 ‐ Development, peak and decline Feb. through April 21 ‐ Abrupt termination between April and May 22 Roelke et al 2010 Roelke et al 2010 120 River flow (10 6 m 3 d -1 ) 0 Lake Granbury Chlorophyll- a Following period of high (µg liter -1 ) inflows inflows Chlorophyll a patches on the scale of 6 km 23 24 Roelke et al 2010 Roelke et al 2010 4

5/25/2010 Salinity, Temperature and P. parvum Growth Cell Density Does Not Always Correlate with Ambient Toxicity Baker et al 2007 Baker et al 2010 Non ‐ optimal growth conditions = ↑ toxicity 25 26 Bloom Dynamics A Decade of Blooms in Timing of blooms Lakes Possum • wintertime phenomena Kingdom, Granbury, • environmental conditions far removed from the Whi Whitney on the Brazos h B optimum conditions for growth ti diti f th • concurrent in each reservoir River, Texas Magnitude of blooms • higher population densities before Spring 2007 • Lake Granbury highest densities 27 28 Roelke et al. accepted. J. Plank Res Roelke et al. accepted. J. Plank Res Bloom Dynamics Bloom Dynamics Hydrology Thresholds Identified Salinity Thresholds Identified (7 ‐ day accumulated inflow) • ~1.5 psu for Lake Possum Kingdom • ~10 x10 6 m 3 Lake Possum Kingdom (0.01 d ‐ 1 ) • 0.5 psu for Lakes Granbury and Whitney • ~20 x10 6 m 3 Lake Granbury 3 L k G 20 10 6 (0.12 d ‐ 1 ) (0 12 d 1 ) b Relationship non ‐ monotonic • ~40 x10 6 m 3 Lake Whitney (0.10 d ‐ 1 ) linear function (41%) Bloom termination power function (40%) • high inflows not a requirement exponential function (35%) 29 30 Roelke et al. accepted. J. Plank Res Roelke et al. accepted. J. Plank Res 5

5/25/2010 Locations of fish kills attributed to P. parvum pH and P parvum pH and P. parvum 31 32 Southard, Fries, Barkoh. 2010. Highest ambient toxicity coincident with highest pH 120 River flow 10 6 m 3 d -1 Brazos River 0 Watershed Generally, higher pH Lower pH 33 34 Valenti et al 2010a, Roelke et al 2010 Why is toxicity to fish and daphnia influenced by pH? Ambient toxicity to fish/daphnia is influenced by pH [ F/2 Nutrient ] NO CELLS 100 FHM LC 50 value 80 (% media) 60 40 20 0 6.5 6.5 7.5 7.5 8.5 8.5 [ F/8 Nutrient ] pH NO CELLS 15 FHM LC 50 value (% media) 10 5 0 6.5 7.5 8.5 pH ‐ similar to previous studies with fish and pH at higher salinities ‐ but with lower pH hemolysis reported to increase 35 Valenti et al 2010a 36 Valenti et al 2010a 6

5/25/2010 Why is toxicity to fish and daphnia influenced by pH? Sunlight and P parvum Sunlight and P. parvum ‐ other toxins? 37 38 Valenti et al 2010a,b BU, TAMU, UTA Toxicity to fish ameliorated by full and partial sunlight Study 1. Natural sunlight influences on aquatic toxicity of cell free P. parvum cultures (8 hrs) ‐ Three treatment levels 100 urvivorship (%) Survivorship (%) 100 90 90 No Sunlight 80 Lab Dark Control 80 70 70 Full Sunlight Pimephales promelas Su Partial Sunlight a t a Su g t 60 60 Pimephales promelas S 60 No Sunlight 50 Lab Dark Control 50 40 40 30 30 20 20 10 LT 50 = 2.3 hrs 10 0 0 0 1 2 3 4 5 6 7 8 9 10 0 10 20 30 40 50 60 70 80 90 100 Prymnesium parvum Cell-Free Filtrate (%) Exposure Time (hrs) Full Sun ~50% Sun No Sun 39 40 James et al, Accepted. J. Plank Res James et al, Accepted. J. Plank Res BU, TAMU, UTA BU, TAMU, UTA Study 2. Natural sunlight influences on aquatic toxicity Recall some aquatic chemistry and toxicology principles… of cell free P. parvum cultures (0.5, 1, 2, 4, 8 hrs) ‐ Two treatment levels, varied exposure durations 1/LC 50 C 0 /C t Full Sun No Sun Time Time t 1/2 James et al, Accepted. J. Plank Res 41 42 7