Pelagic and epiphytic summer distributions of Prorocentrum lima and P. mexicanum at two mussel farms in the Gulf of St. Lawrence, Canada

Abstract

The variations in abundance of Prorocentrum lima (Ehrenberg) Stein, an epiphythic species implicated in diarrhetic shellfish poisoning (DSP), were studied during the summer of 1999 in the Magdalen Islands, an archipelago located in the southern Gulf of St. Lawrence, eastern Canada. This investigation was initiated as a result of an incident in 1998, when 20 people became ill and exhibited DSP-like symptoms following the consumption of blue mussels collected from one of the Magdalen Islands lagoons. P. lima was regularly found as an epiphyte on the epibionts growing on the mussel socks at the 2 aquaculture sites investigated between June and October 1999. P. lima abundance on the epibionts varied from 100 to 9600 cells g -1 dry wt epibiont, with maximum abundances observed in July and August. P. lima was found in low abundance in the water column as well as in the digestive glands of the mussels. There was no correlation between cell abundances in the digestive glands, the water column and the cells attached to the epibionts. At the same sites, P. mexicanum Tafall was identified for the first time in eastern Canada. P. mexicanum abundances were low throughout the summer and began to increase both in the water column and in mussel digestive glands by early September. A significant correlation was found between the P. mexicanum abundances in the water column and in the mussel digestive glands at both sampling sites. The identification of these 2 potentially toxic species in the St. Lawrence highlights the importance of Prorocentrum spp. as toxin producers in coastal waters, as well as the need for adequate monitoring of non-pelagic harmful algal bloom species (HABs). KEY WORDS: Prorocentrum lima · Prorocentrum mexicanum · Diarrhetic shellfish poisoning · Epiphytes · Mussel culture · Toxic dinoflagellate · Biofouling community Resale or republication not permitted without written consent of the publisherAquat Microb Ecol 30: [283][284][285][286][287][288][289][290][291][292][293] 2003 after consuming cultured blue mussels from Mahone Bay, Nova Scotia (Quilliam et al. 1993). The DSP toxins found in the mussels were not associated with the Dinophysis-rich samples collected following the incident. However, another dinoflagellate, Prorocentrum lima (Ehrenberg) Stein, isolated from the same area, was found to be a producer of okadaic acid (OA) and dinophysistoxin-1 (DTX-1) in unialgal cultures (Marr et al. 1992). A study carried out later by Lawrence et al. (1998) suggested that P. lima could have been responsible for the accumulation of DSP toxins at this site. Similarly, on the east coast of Maine, USA, following several unexplained incidents of shellfish-related gastroenteritis, Morton et al. (1999) showed that DSP toxicity was found only in phytoplankton or mussel digestive gland samples containing P. lima. P. lima occurs worldwide in coastal areas, in temperate and tropical oceans and mostly in benthic and epiphytic habitats (Faust et al. 1999). In eastern Canada, this dinoflagellate has already been ...

Morphological and genetic characterization of benthic dinoflagellates of the generaCoolia,OstreopsisandProrocentrumfrom the south-eastern Bay of Biscay

“…Coolia monotis is frequently found both in temperate as well as in tropical areas (Meunier, 1919;Penna et al, 2005;Aligizaki & Nikolaidis, 2006;Dolopsakis et al, 2006) and the P. lima complex has also been reported from temperate areas (e.g. Faust, 1991;Bravo et al, 2001;Levasseur et al, 2003;Foden et al, 2005;Maranda et al, 2007;Aligizaki et al, 2009) in addition to tropical ones. (Fig.…”

“…Outside tropical and subtropical areas, Ostreopsis is very frequent and well-documented in the Mediterranean Sea (Vila et al, 2001;Turki, 2005;Aligizaki & Nikolaidis, 2006;Ciminiello et al, 2006;Mangialajo et al, 2008;Totti et al, 2010) and reports of blooms in temperate waters have increased in recent years (Shears & Ross, 2009;Rhodes, 2010). Coolia and Prorocentrum appear to be more widely distributed, extending to colder waters than Gambierdiscus and Ostreopsis (Faust, 1991;Bravo et al, 2001;Levasseur et al, 2003;Nascimento et al, 2005;Maranda et al, 2007;Vale et al, 2009).…”

Phytoplankton functional groups and harmful algae species in anthropogenically impacted waters of the NW Mediterranean Sea

“…In this study, blooms >10 6 cells l -1 were only detected in Alexandrium minutum and Pseudo-nitzschia. ** It is not a true DSP-producing species as it does not produce okadaic or dinophysistoxin, but it has been related to diarrhetic symptoms (Levasseur et al, 2003).…”

Cambios estacionales en conjuntos de dinoflagelados epifíticos cerca de la costa norte de la Península de Yucatán, Golfo de México

“…While seasonality and annual cycles of phytoplankton communities, including mainly diatoms and dinoflagellates, have been repeatedly investigated throughout the oceans, studies of the annual dynamics of epiphytic/epibenthic dinoflagellates are still scarce. The major exception is studies that have followed the seasonality of individual species that were thought to cause ciguatera (Bagnis et al, 1985;Carlton & Tindall, 1985;Gillespie et al, 1985;Mitchell, 1985;Ballantine et al, 1988;Bomber et al, 1988;Tindall & Morton, 1998;Chinain et al, 1999;Vila et al, 2001;Levasseur et al, 2003). Habitat preference, the influence of environmental factors and population dynamics of the epiphytic dinoflagellates are still poorly known (Richlen & Lobel, 2011).…”