A. Brief summary of A. fundyense bloom and toxicity patterns for the years that

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1 A. Brief summary of A. fundyense bloom and toxicity patterns for the years that relate to those in which cyst surveys were conducted This was a year of low shellfish toxicity in the WGOM and EGOM and BOF. Toxicity was of limited extent in the WGOM and EGOM (see Kleindinst et al., this issue), with 112 km of closures in the former, and only 14 in the latter, for a total of 126 km closed (~18% of the 705 km coastline of the combined WGOM and EGOM region). No Alexandrium bloom survey data are available for the GOM. Although Alexandrium cells were observed from mid-may through December in the BOF, highest concentrations observed were very low - 8,200 cells L -1 in late June, and the highest toxicity in soft-shell clams (Mya arenaria) was relatively low at 920 µg saxitoxin equivalents (STX eq.) 100 g -1. During most years, a significant portion of the southwest New Brunswick coastline of the BOF is closed to harvesting of shellfish, but in 1997, there were only isolated, shortterm closures This was a year of limited toxicity in the WGOM and EGOM, with 163 km of combined coastline closed (131 in the WGOM and 32 km in the EGOM, 23% of the WGOM and EGOM total). Maximum Alexandrium cell concentrations near Casco were ~ 1,000 cells L -1 in May during the peak of shellfish toxicity in the WGOM (Keafer et al., 2005), while Townsend et al. (2001) present Alexandrium bloom survey data for June, July, and August 1998, documenting a coastal bloom that extended only into western Maine at its largest extent. No toxicity was reported in New Hampshire or Massachusetts. In the BOF, 1998 was an exceptionally low toxicity year in that many of the shellfish beds that typically have annual summertime closures for PSP did not experience closures at all. Shellfish beds were closed for a short period and at only

2 isolated locations. The highest PSP value detected in M. arenaria in the BOF was 360 µg STX eq. 100 g -1, and the highest concentration of Alexandrium was also very low 6,720 cells L This was a year of moderate shellfish toxicity in the region, with a total of 345 km of WGOM or EGOM coastline closed (49% of the total: 202 km in the WGOM and 145 in the EGOM). No Alexandrium bloom survey data are available for the GOM. A fall A. fundyense bloom likely occurred in eastern Maine, as a new pulse of toxicity was detected in shellfish (the mahogany clam Arctica islandica) in September (Anderson et al., 2013 this issue Supplementary Materials) was a year of high toxicity in the BOF. All shellfish beds were closed to harvesting during some of the year, with many closed from May to the end of the year and into The highest M. arenaria toxicity was 1,468 µg STX eq. 100 g -1. The highest Alexandrium cell concentration was 319,056 cells L -1. Cells were first observed in coastal waters in early May and persisted at low cell densities through early November. Mortalities as a result of PSP toxins occurred at a number of BOF salmon aquaculture sites in 2004 (Martin, et al., 2008) There was a major (extensive) toxicity outbreak in the WGOM and EGOM regions, with closures extending over 537 km (76% of the total coastline: 391 km in the WGOM and 146 in the EGOM). The WGOM experienced shellfish toxicity levels and geographic impact that had not been documented at such levels for nearly two decades, since the 1980s (Anderson et al., 2013 this issue ). There were record levels of toxicity in some locations, first-time ever records of toxicity in others, large closure of federal (offshore) waters, and federal disaster declarations declared for the states of Maine, New

3 Hampshire, and Massachusetts (Anderson et al., 2005b; Kleindinst et al., 2013 this volume ). A single, large-scale survey cruise was conducted in May, 2005, revealing the early stages of this bloom in the WGOM (Anderson et al., 2005b). Other smaller-scale survey data are available in the Massachusetts (MB) region, documenting high levels of cells observed in that bay, as well as the progression of the bloom into the waters of outer Cape Cod and the islands of Martha's Vineyard and Nantucket (see Section C). Alexandrium concentrations in 2005 in the BOF were significantly lower than in Several shellfish harvesting areas that were closed throughout 2004 with toxicity persisting into 2005 remained closed through The highest toxicity detected in M. arenaria in 2005 was 1,555 µg STX eq. 100 g -1. Highest Alexandrium concentrations were 52,480 cells L This was another extensive outbreak year in the WGOM and EGOM subregions, with 417 km of coastline closed due to PSP toxins (59% of the total coastline: 286 km in the WGOM and 131 in the EGOM). One large-scale Alexandrium survey was conducted, documenting a bloom extending from eastern Maine into Massachusetts (see Supplementary Materials). In the BOF, the Alexandrium bloom was moderate - similar to 2005 with highest concentrations observed in late July (49,408 cells L -1 ). The highest toxicity in M. arenaria was 337 µg STX eq. 100 g -1. Most shellfish harvesting areas were closed for a normal amount of time This was a moderate year for shellfish toxicity in the WGOM and EGOM, with 318 km closed (45% of the total: 222 km in the WGOM and 96 in the EGOM). Survey cruise data document a late start to the coastal bloom in the WGOM, with low

4 Alexandrium cell abundance at times when previous years had well-established blooms in the WGOM subregion. Toxicity eventually developed in eastern Maine and extended into western sections, but never reached New Hampshire or Massachusetts. Survey data are also available documenting A. fundyense blooms on Georges Bank in late May, late June, and October (McGillicuddy et al., 2013b this issue ). During the October cruise, samples were also examined in eastern Maine, revealing a late-season A. fundyense bloom in that area with high cell concentrations (>30,000 cells L -1 ; see Supplementary Materials). In the BOF, there was an extensive bloom of Alexandrium, however, these high cell concentrations were not reflected in shellfish toxicity scores for this region. Shellfish contamination requires certain meteorological conditions to direct high cell concentrations into the inshore shellfish beds, conditions that were not observed in the BOF in Alexandrium concentrations as high as 503,438 cells L -1 were observed in late July. The highest toxicity in M. arenaria (640 µg STX eq. 100g -1 ) was detected at that same time, and thus did not reflect the high cell densities. Although there were closures of shellfish harvesting areas in the BOF, the closures were for short periods This was an extensive year for toxicity in the WGOM and EGOM, with 458 km closed overall (65% of the total: 335 km in the WGOM and 123 in the EGOM). Toxicity extended from Maine through New Hampshire and into Massachusetts. Survey cruise data are available only for the WGOM in late April and late May, and for Georges Bank for those two months as well as late June (McGillicuddy et al., 2013b this issue ). In the BOF, the Alexandrium bloom was large and of similar magnitude to those observed in 2003 and The highest concentration of Alexandrium observed from regular weekly monitoring stations was 460,088 cells L -1, but again, the shellfish toxicities did not reflect

5 the large size of the bloom. The highest M. arenaria toxicity was observed in mid July with 1056 µg STX eq. 100 g -1 ). Closures of shellfish beds were for short periods at most locations This was an extensive year for toxicity in the WGOM and EGOM, with 465 km closed overall (298 in the WGOM and 167 in the EGOM, 66% of the total). Toxicity extended from Maine through New Hampshire and into Massachusetts. An unusual spike in toxicity in early and mid-july resulted in levels not documented since the 1980s in the WGOM, breaking all toxicity records for the EGOM (Anderson et al., 2013 this issue ). No large-scale cruise survey data are available, but a limited dataset for a localized redwater event near Portsmouth, NH is presented in McGillicuddy et al. (2013a this issue ) was an unusual year in the BOF in that very high Mya arenaria toxicities (4,120 µg STX eq. 100g -1 ) were the highest on record for Passamaquoddy, an area that often has much lower toxicity than elsewhere in the BOF. The highest Alexandrium concentrations in 2009 (280,000 cells L -1 ) from regular weekly monitoring stations were also observed in Passamaquoddy. During all other years the Alexandrium bloom has concentrated outside Passamaquoddy in areas exposed to the major seedbeds in the central BOF. Highest Alexandrium numbers elsewhere in the BOF were 183,000 cells L -1 and shellfish beds were closed for a normal period of time (from May to the end of August) This was a moderate year for toxicity in the WGOM and EGOM, with 277 km of coastline closed (39% of the total coastline: 110 km in the WGOM and 167 in the EGOM). Survey cruise data are available for the WGOM and Georges Bank in early May, late May, late June, and late July (McGillicuddy et al., 2011; 2013b this issue ).

6 The BOF experienced a moderate year with some closures extending from May end of August. The highest Alexandrium concentration from regular weekly monitoring stations - 58,000 cells L -1 was recorded in late June; however, the bloom initiated in mid-march and extended through to early August This was a moderate year for toxicity in the WGOM and EGOM, with 361 km of coastline closures (51% of the total coastline: 295 in the WGOM and 66 in EGOM). No cruise survey data are available was a lower than normal year for shellfish toxicity through all the BOF except Passamaquoddy, where toxicity was slightly higher than normal. Highest Alexandrium concentrations observed from regular weekly monitoring stations outside Passamaquoddy were 103,500 cells L -1. Shellfish beds were closed for a typical amount of time (from May to the end of August). REFERENCE Martin, J.L, LeGresley, M.M., Hanke, A., Page, F.H., Alexandrium fundyense - red tides, PSP shellfish toxicity, salmon mortalities and human illnesses in before and after. Proceedings of the 12th International Conference on Harmful Algae. International Society for the Study of Harmful Algae and Intergovernmental Oceanographic Commission of UNESCO, Copenhagen

7 B. Alexandrium cell distribution maps: 2005 Alexandrium surveys:

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14 2008 Alexandrium surveys:

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19 2008 Alexandrium rapid response surveys:

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26 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (14 km) Portland 43 NH WGOM (0 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

27 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (14 km) Portland 43 NH WGOM (112 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

28 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (32 km) Portland 43 NH WGOM (131 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

29 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (113 km) Portland 43 NH WGOM (265 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

30 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (145 km) Portland 43 NH WGOM (202 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

31 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (146 km) Portland 43 NH WGOM (391 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

32 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (131 km) Portland 43 NH WGOM (286 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

33 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (96 km) Portland 43 NH WGOM (222 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

34 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (123 km) Portland 43 NH WGOM (335 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

35 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (167 km) Portland 43 NH WGOM (298 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

36 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (167 km) Portland 43 NH WGOM (110 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

37 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (66 km) Portland 43 NH WGOM (295 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map

38 Canada 45 Trescott 44 ME Casco Penobscot Rockland Isle au Haut Corea EGOM (155 km) Portland 43 NH WGOM (219 km) Gloucester 42 RI Boston MA Mass. CC 41 Buzzards 40 PSP closure map