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Bibliography of the Maurice Lamontagne Institute

Laure DEVINE

GALBRAITH, P.S., J. CHASSÉ, D. GILBERT, P. LAROUCHE, D. BRICKMAN, B. PETTIGREW, L. DEVINE, A. GOSSELIN, R.G. PETTIPAS, C. LAFLEUR, 2011. Physical oceanographic conditions in the Gulf of St. Lawrence in 2010 ; Conditions océanographiques physique dans le golfe du Saint-Laurent en 2010. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2011/045, 86 p .

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An overview of physical oceanographic conditions in the Gulf of St. Lawrence in 2010 is presented. Air temperatures reached record highs when averaged from January to March and from October through December as well as annually. The monthly averaged freshwater runoff measured at Québec City was normal overall in 2010 but was unusually high during winter and fall, and the spring freshet was almost absent. Near-surface water temperatures in the Gulf were normal or above normal all year and in all regions except for the Mécatina Trough and Esquiman Channel in June. Maximum sea-ice volume within the Gulf and on the Scotian Shelf was 11 km³, a record low since 1969. The duration of the 2009–2010 ice season was shorter than normal and associated with the early ice melt. Winter inflow of cold and saline water from the Labrador Shelf occupied the Mécatina Trough over the entire column in winter 2010. The spread of the intrusion was confined close to the Strait of Belle Isle, leading to an overall small volume of 809 km³. However, this intrusion volume represented 29 % of the unusually small volume of mixed layer waters that were colder than -1 °C. The winter cold mixed layer volume in the Gulf, excluding the Estuary, was 13 900 km³, a value higher than the 1996–2009 average by 0.7 SD. This cold-water volume corresponded to 42 % of the total water volume of the Gulf. However, it was very warm, on average about 1 °C above the freezing point. This is the first time in 15 years of winter surveys that such high temperatures were recorded. The cold intermediate layer (CIL) index for summer 2010 was - 0.04 °C, which is similar to observations in 2000. This is an increase of 0.38 °C since 2009. On the Magdalen Shallows, none of the bottom area was covered by water with temperatures < 0 °C in September 2010, similar to conditions in 2005, 2006, 2007, and 2009. In other regions of the Gulf, very few areas had bottom temperatures below 0 °C. Regional patterns of the August and September CIL show that the layers for T < 1 °C and < 0 °C were much thinner in most parts of the Gulf in 2010 than in 2009 and had a generally higher core temperature everywhere. Conditions in March 2010 were characterized by a very thick winter mixed layer, although very warm, including a thick intrusion of Gulf waters into the Estuary. By June 2010, the CIL thickness returned to nearnormal but still had above-normal minimum temperatures. The CIL warming rate appeared to be slower than usual because core temperatures were closer to normal in certain regions by August and more so by November. The warm deep waters in the Estuary in 2009 were replaced by colderthan- normal waters by June 2010. Colder-than-normal deep waters also occupied the northwest Gulf at that time. Very warm waters occupied Cabot Strait in June at 250 m—the depth of the temperature maximum—and there is a hint that the top portion of this water mass was sampled during the March survey. The warm deep waters were still present in Cabot Strait in August as well as in November. Gulf-wide average temperatures were below normal at 200 to 300 m and salinities were below normal from 150 to 300 m. Temperatures at 300 m increased marginally overall but significantly (by 1 SD) at Cabot Strait, where the anomaly is now +1 SD. Salinity at 200 m and 300 m decreased overall by 0.6 SD but increased at Cabot Strait to reach +0.6 SD at 200 m. The 300 m waters of the Estuary are expected to cool further during the next two years, but it will be interesting to follow the warm anomaly present in 2010 at Cabot Strait as it progresses up the channel toward the Estuary. The surface mixed layer in November was anomalously thick but more importantly very warm, warmer in fact than in November 2009 which were the preconditions for the record conditions of March 2010.

DUFOUR, R., H. BENOIT, M. CASTONGUAY, J. CHASSÉ, L. DEVINE, P. GALBRAITH, M. HARVEY, P. LAROUCHE, S. LESSARD, B. PETRIE, L. SAVARD, C. SAVENKOFF, L. ST-AMAND, M. STARR, 2010. 2010 Canadian marine ecosystem status and trends report. Advis. Sec. Sci. Advis. Rep. 2010/030(Revised), 38 p .

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GALBRAITH, P.S., R.G. PETTIPAS, J. CHASSÉ, D. GILBERT, P. LAROUCHE, B. PETTIGREW, A. GOSSELIN, L. DEVINE, C. LAFLEUR, 2010. Physical Oceanographic Conditions in the Gulf of St. Lawrence in 2009 Conditions d’océanographie physique dans le golfe du Saint-Laurent en 2009. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2010/035, 77 p .

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An overview of physical oceanographic conditions in the Gulf of St. Lawrence in 2009 is presented. Air temperatures were close to normal when averaged from January to March. Air temperatures were in general either normal or above normal for the remainder of the year. The monthly averaged freshwater runoff measured at Québec City was normal overall in 2009 but consisted of aboveaverage runoff in July compensated later by lower runoff in the fall. Near-surface water temperatures in the Gulf were above normal in all regions except the Northwest Gulf and the Estuary in June and in every region in August. Maximum sea-ice volume within the Gulf and on the Scotian Shelf was 65 km³, a value that is below normal using updated ice volume estimates for 1971-2000. The duration of the 2008-09 ice season was longer than normal in the Estuary, normal in the central Gulf and Cabot Strait, and shorter elsewhere. This was mostly associated with the variability of the first occurrence of ice. Winter inflow of cold and saline water from the Labrador Shelf occupied the Mécatina Trough over the entire column in winter 2009. The spread of the intrusion was confined a bit closer to the coast compared to 2008 conditions, leading to an overall smaller volume of 1270 km³, which is similar to the 2002 observations. The winter cold mixed layer volume in the Gulf, excluding the Estuary, was 14 000 km³, a value higher than the 1996–2009 average by 0.7 SD. This cold-water volume corresponded to 42% of the total water volume of the Gulf. The cold intermediate layer (CIL) index for summer 2009 was -0.42°C, which is similar to observations in 2002, 2004, 2005 and 2007. This is an increase of 0.32°C since 2008. On the Magdalen Shallows, almost none of the bottom area was covered by water with temperatures < 0°C in September 2009, similar to conditions in 2005, 2006 and 2007. Regional patterns of the August and September CIL show that the layers for T < 1°C and < 0°C were much thinner in most parts of the Gulf in 2009 than in 2008 and had a generally higher core temperature everywhere. In the northern Gulf, the area covered by low temperature water (< 1°C) decreased in 2009 relative to 2008 conditions. Temperatures in March 2009 were characterized by a very thick cold layer, including a thick intrusion of Gulf CIL waters into the Estuary. By June 2009, CIL temperatures returned to normal with a warming trend that continued into August, especially on the Magdalen Shallows. By October–November, CIL conditions were normal in most regions except the estuary and Northwest Gulf, where the CIL and the surface mixed layer were anomalously deep. Overall, temperature and salinity were generally normal from 150 m to 200 m, and slightly lower than normal at 250 and 300 m. Temperature and salinity at 300 m decreased for a third consecutive year, from 2008 to 2009. The lower-than-normal Gulf-wide water temperatures at 300 m were composed of normal waters in the Estuary and northwest and colder waters in the centre and coming into the Gulf at Cabot Strait. This cold anomaly has propagated inward in the last few years and is expected to continue toward the Estuary during the next few years.

DUFOUR, R., H. BENOIT, M. CASTONGUAY, J. CHASSÉ, L. DEVINE, P. GALBRAITH, M. HARVEY, P. LAROUCHE, S. LESSARD, B. PETRIE, L. SAVARD, C. SAVENKOFF, L. ST-AMAND, M. STARR, 2010. Rapport sur l'état et les tendances des écosystèmes marins canadiens en 2010. MPO, Secrétariat canadien de consultation scientifique, Avis scientifique, 2010/030(révisé), 43 p .

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DUFOUR, R., H. BENOIT, M. CASTONGUAY, J. CHASSÉ, L. DEVINE, P. GALBRAITH, M. HARVEY, P. LAROUCHE, S. LESSARD, B. PETRIE, L. SAVARD, C. SAVENKOFF, L. ST-AMAND, M. STARR, 2010. Ecosystem status and trends report: Estuary and Gulf of St. Lawrence ecozone. Rapport sur l’état et les tendances des écosystèmes : écozone de l’estuaire et du golfe du Saint Laurent. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche; 2010/030, 193 p .

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This document was produced under the umbrella of the national ecosystem status and trends report program and deal with the estuary and gulf of St.Lawrence ecozone. It is structured around the status and trends of some important marine species and physico-chemical variables of the ecosystem. The national ecosystem status and trends report will support prioruty-setting for a national biodiversity agenda and will integrate national and provincial exosystem-bases information. It will report on many large terrestrial and marine ecozones.

HARVEY, M., L. DEVINE, 2010. Nine years of zooplankton monitoring in the St.Lawrence Marine System (2001-2009). AZMP Bull. PMZA, 10: 32-36 .

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HARVEY, M., L. DEVINE, 2009. Oceanographic conditions in the Estuary and the Gulf of St. Lawrence during 2008 : zooplankton ; Conditions océanographiques dans l’estuaire et le golfe du Saint-Laurent en 2008 : zooplancton. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2009/083, 60 p .

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This document provides an overview of the temporal variability of zooplankton biomass, abundance, and species composition in 2008 at four fixed stations and seven sections of the AZMP as well as an overview of the interannual variability of the macrozooplankton species composition, abundance, and biomass in the Lower St. Lawrence Estuary (LSLE) and the northwest Gulf of St. Lawrence (NWGSL) from 1994 to 2008. Compared to the 1999–2007 average, the state of the zooplankton at the four Québec fixed stations in 2008 was estimated as lower than normal (zooplankton biomass) and above normal (total non-copepod abundance, total copepod abundance, Calanus finmarchicus abundance, Pseudocalanus spp. Abundance) at AG and GC; lower than normal (zooplankton biomass), normal (total non-copepod abundance, total copepod abundance, Pseudocalanus spp. Abundance), and above normal (C. finmarchicus abundance) at RS; and normal (zooplankton biomass, C. finmarchicus abundance, Pseudocalanus spp. Abundance) and above normal (total non-copepod abundance, total copepod abundance) at SV. In addition, some changes in the zooplankton community structure were observed over the time series, including some changes in the rank of the top ten taxa and the appearance of new taxa in the dominant species (top ten): Temora spp. And appendicularians at AG; Temora spp., cladocera, and bivalve larvae at GC; Paraeuchaeta norvegica and Calanus glacialis at SV; and polychaete larvae at RS. The biomass indices of Calanus hyperboreus and the mesozooplankton along the seven Québec sections in spring and fall 2008 were estimated to be normal or below normal except in the LSLE (TESL), where the C. hyperboreus biomass was evaluated as above normal. For the nine zooplankton abundance indices, most were evaluated as normal or above normal in spring 2008 except that below normal abundances were found for copepod nauplii along the TESL and TIDM sections, for mesozooplankton (excluding copepods) in the centre and the northeast GSL (TCEN, TBB), and for krill larvae in Cabot Strait (TDC). The situation was very different for the fall period: some of the abundance indices were still evaluated as normal or above normal (total copepods, copepod nauplii, small copepods, carnivorous zooplankton, mesozooplankton excluding copepods, krill larvae) and some others as normal or below normal (large copepods, C. finmarchicus CIV–CV, meroplankton). In addition, some changes in zooplankton composition were observed over the time series in each region, including some changes in the rank order of the top ten taxa and the appearance of new taxa in the top ten species: Eurytemora spp. And C. Glacialis in the LSLE (TESL); Temora spp. And copepod eggs in the northwest GSL (TSI); copepod eggs southwest of Anticosti Island (TASO); Paraeuchaeta norvegica and C. glacialis in the centre GSL (TCEN); C. glacialis in the northeast and southern GSL (TBB, TIDM); and Ostracoda in Cabot Strait (TDC). The mean mesozooplankton biomass observed in November 2008 in the LSLE and in the NWGSL was 1.8 and 1.4 times higher than in 2006 and 2007, respectively. This corresponds to the second highest value observed in the last 15 years in the study area. The mean macrozooplankton biomass decreased from 15.4 ww g/m2 in 2005 to 5.9 (2006), 8.6 (2007), and 6.2 (2008). The macrozooplankton biomass values observed in 2006, 2007, and 2008 correspond to the lowest values observed over the last 15 years. The most notable feature observed in the LSLE and NWGSL was the sharp decrease in the abundance of Thysanoessa raschii, which was 5.3 times less abundant in 2006, 2007, and 2008 compared to the previous 15 years. In addition, the mean abundance of the hyperiid amphipod Themisto libellula estimated in both regions in 2006, 2007, and 2008 corresponds to the lowest value observed over the previous last 15 years (except 2000).

GALBRAITH, P., R.G. PETTIPAS, J. CHASSÉ, D. GILBERT, P. LAROUCHE, B. PETTIGREW, A. GOSSELIN, L. DEVINE, C. LAFLEUR, 2009. Physical oceanographic conditions in the Gulf of St. Lawrence in 2008 ; Conditions d’océanographie physique dans le golfe du Saint-Laurent en 2008. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2009/014, 73 p .

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An overview of physical oceanographic conditions in the Gulf of St. Lawrence in 2008 is presented. Air temperatures were close to normal when averaged from January to March, contributing to an ice cover volume that was also close to the climatological mean. Air temperatures were in general either normal or above normal for the remainder of the year. The monthly averaged freshwater runoff measured at Québec City was normal overall in 2008, but consisted of above-average runoff in summer compensated later by lower runoff in the fall. The high summer runoff contributed to higher-than-normal stratification. Near-surface water temperatures were generally above normal throughout the Gulf for the months of May, July and November and were also above-normal on the Magdalen Shallows in June and in the northern Gulf from August to October. In August the northern parts of the Gulf saw positive anomalies while the southern parts experienced negative anomalies. This lead to the unusual occurrence that the waters around Prince Edward Island and in Northumberland Strait had higher temperature in July than in August 2008. On the Magdalen Shallows, a large area of the bottom was covered by water with temperatures < 0 °C in September 2008, similar to the cold period observed in the 1990s and in contrast to conditions in September 2005, 2006 and 2007 when such cold waters were not observed. Maximum sea-ice volume within the Gulf and on the Scotian Shelf was 81 km3, a value now considered about normal using updated ice volume estimates for 1971-2000. Ice first appeared early in the season and stayed later than normal (later by about 8 days later on the Magdalen Shallows). Winter inflow of cold and saline water from the Labrador Shelf occupied the Mécatina Trough from top to bottom in winter 2008. The spread of the intrusion was confined a bit closer to the coast compared to 2007 conditions, leading to an overall smaller volume of 1850 km3, which is similar to 2001 and 2006 observations. The winter cold mixed layer volume was 13 700 km3, a value higher than the 1996–2008 average by 0.8 SD, and corresponded to 41 % of the total water volume of the Gulf. The summer CIL (cold intermediate layer) index for 2008 was -0.70 °C, comparable to the very cold conditions observed in 2003 and a large decrease (by 0.47 °C) from the previous summer. Regional patterns of the August and September CIL show that the layers for T < 1 °C and < 0 °C were much thicker in most parts of the Gulf in 2008 than in 2007 and had a generally lower core temperature throughout the Gulf. In the Northern Gulf, the area covered by water of low temperature (from < -1 °C through < 1 °C) increased in August 2008 relative to August 2007. Temperatures in the water column in June 2008 were characterized by a very thick and cold CIL in most regions except the Estuary and by warm deep waters in the Estuary and the northwest Gulf. This overall pattern persisted in the August– September mean conditions. By October and into November, CIL conditions were still thick and cold, while waters above the CIL were anomalously warm. Overall, temperature and salinity were generally normal from 150 m to 300 m, with the exception of slightly lower than normal (by 0.6 SD) temperature at 150 m. Temperature and salinity in this depth range decreased for a second consecutive year. The near-normal Gulf-wide water temperatures at 300 m were composed of warmer waters in the Estuary, near-normal temperatures in the northwest and central, and colder waters flowing into the Gulf at Cabot Strait.

GALBRAITH, P.S., D. GILBERT, R.G. PETTIPAS, J. CHASSÉ, C. LAFLEUR, B. PETTIGREW, P. LAROUCHE, L. DEVINE, 2008. Physical oceanographic conditions in the Gulf of St. Lawrence in 2007 ; Conditions d'océanographie physique dans le golfe Saint-Laurent en 2007. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2008/001, 59 p .

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An overview of physical oceanographic conditions in the Gulf of St. Lawrence in 2007 is presented. Air temperatures ranged from normal to cooler than normal for most of the year in the western parts of the Gulf; however, the eastern regions were only significantly cooler than normal in April and May. Averaged over the whole Gulf for the entire year, air temperature was normal. The monthly averaged runoff at Québec City was below normal during all months of 2007. Near-surface water temperatures were much cooler in 2007 overall than in 2006 in all regions of the Gulf. Near-surface waters were warm in the St. Lawrence Estuary in January and February. Summer maximum surface temperatures occurred earlier than usual, followed by earlier-than-usual cooling. Surface temperatures were generally below normal for the rest of the year except for October in the Estuary. On the Magdalen Shallows, there was (almost) no bottom area covered by water with temperatures <0 °C in September 2007. Maximum sea-i ce volume within the Gulf and on the Scotian Shelf was below normal but still much higher than the volume recorded in 2006. Winter inflow of cold and saline water from the Labrador Shelf occupied the Mecatina Trough from top to bottom. The spread of the intrusion had an area similar to that of 2006, but its volume was much larger and similar to that observed in 2004. The winter cold mixed layer volume was 13100 km3, slightly above the 1996-2007 average, and corresponded to 39 % of the total water volume of the Gulf. The higher winter volume of cold water compared with 2006 conditions led to a decrease of 0.44 °C in the Cold Intermediate Layer (CIL) index, reaching -0.23 °C in summer 2007, which is comparable to conditions observed in 2004. The index saw a large decrease after three consecutive years of warming. Regional patterns of the CIL show that the layer for T < 1 °C and < 0  °C was much thicker in the northern half of the Gulf in 2007 than in 2006 and had a generally lower core temperature almost everywhere as well. Seasonal and regional patterns of water column temperatures in June were generally close to the 1971-2000 climatology at all depths, except for the very thick and cold CIL in the Anticosti Channel and warm deep waters in the northwest. This overall pattern persisted from August to September, but by late fall conditions were about normal everywhere except for the anomalously warm nearsurface mixed layers in the northwest and warm near-surface waters on the Magdalen Shallows and in Cabot Strait. Averaged annually for the entire Gulf, the temperature and salinity from 150 m to 300 m were normal in 2007. Spatially, at 300 m, this was composed of warmer than normal waters near the Estuary, near-normal temperatures in the centre and colder than normal waters coming into the Gulf at Cabot Strait. The outlook for 2008 from the March 2008 survey is for a slight cooling of the CIL index to -0.47 °C resulting from a thicker cold winter surface layer.

DEVINE, L., C. LAFLEUR, 2008. Quality Control of Bottle Data at Maurice Lamontagne Institute;Contrôle de qualité des données bouteilles à l'Institut Maurice-Lamontagne. AZMP Bull. PMZA, 7: 27-37 .

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This article describes the quality control tests that we at Maurice Lamontagne Institute (MLI) apply to data collected from water samples before the dataset is distributed and archived. The tests verify important metadata (sampling time and location) and examine the data from various perspectives, allowing the data manager to make judgments on the data’s quality.

HARVEY, M., L. DEVINE, 2008. Oceanographic conditions in the Estuary and the Gulf of St. Lawrence during 2007 : zooplankton ; Conditions océanographiques dans l'estuaire et le golfe du Saint-Laurent en 2007 : zooplancton. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2008/037, 39 p .

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Zooplankton biomass, abundance, and species composition in the DFO Quebec Region (Lower St. Lawrence Estuary [LSLE] and the Gulf of St. Lawrence) during 2007 are reviewed and compared to the eight previous observations (1999-2006) at the Anticosti Gyre (AG), the Gaspe Current (GC), and the Shediac Valley (SV) stations and to the two previous years (2005-2006) at the Rimouski (RS) station. In addition, this report gives an overview of the interannual variability in the mesozooplankton biomass and macrozooplankton species composition, abundance, and biomass in the LSLE and northwest Gulf of St. Lawrence (NWGSL) as measured in the fall of each year between 1994 and 2007. The state of the zooplankton at the four Quebec’s fixed stations in 2007 was considered as normal (zooplankton total abundance and copepod total abundance) and lower than normal (zooplankton biomass and Calanus finmarchicus abundance) at the AG station; normal (zooplankton biomass, zooplankton total abundance, and copepod total abundance) and above normal (C. finmarchicus abundance) at the GC station; and normal (C. finmarchicus abundance), lower than normal (zooplankton biomass), and above normal (zooplankton and copepod abundance) at the SV station. The average abundance of C. finmarchicus at RS in 2007 was 2.6 times higher than during the two previous years. In addition, some changes in the zooplankton community structure were observed over the time series at AG, GC, SV and RS including some variations in the rank of the top ten taxa and the appearance for the first time of some new taxa in the dominant species (top ten): appendicularians and Oncaea spp. at AG, echinoderm and bivalve larvae at GC, euphausiids (eggs, nauplii, juveniles) and Calanus glacialis at the RS station, and echinoderm and polychaete larvae at SV. Zooplankton biomass along the seven Quebec sections in spring 2007 was estimated as higher than normal along the Lower St. Lawrence Estuary (TESL), Sept-Îles (TSI), Cabot Strait (TDC), and Îles-de-la-Madeleine (TIDM) sections; normal along the southwest Anticosti (TASO) section; and lower than normal along the Centre Gulf of St. Lawrence (TCEN) and the Bonne Bay (TBB) sections. Concerning the total zooplankton abundance, anomalies were above normal for all sections except for TSI, TDC, and TIDM, where the total abundance of zooplankton was evaluated as normal. On the other hand, during fall, both the total zooplankton biomass and total zooplankton abundance anomalies were normal for all sections except TESL, TSI, and TASO, where these were evaluated as above normal, and along TCEN, where the total biomass was evaluated as lower than normal. In addition, some changes in the zooplankton composition were observed over the time series in each region, including some changes in the rank order of the top ten taxa and the appearance of new taxa in the top ten species: appendicularians, echinoderm larvae, and ostracods in LSLE and the NWGSL, C. glacialis in the NEGSL, pteropods and Oncaea spp. in the southern GSL, and pteropods and Metridia spp. in Cabot Strait. The mean mesozooplankton biomass observed in November 2007 in the LSLE and NWGSL was 1.4 times higher than in 2006 and corresponds to the fourth highest value observed over the last 14 years in the study area. The mean macrozooplankton biomass decreased from 15.4 in 2005 to 5.9 and 8.6 wet weight (g/m²) in 2006 and 2007, respectively. The macrozooplankton biomass values observed in 2006 and 2007 correspond to the lowest values observed over the last 14 years. The most notable feature observed in the LSLE and NWGSL was that 2006-2007 had the lowest mean biomass of euphausiids in our dataset due to a strong decrease in the abundance of Thysanoessa raschii, which was 5.3 times less abundant in 2006-2007 compared to the last 14 years. In addition, the mean abundance of the hyperiid amphipod Themisto libellula estimated in both regions in 2007 corresponds to the lowest value observed over the last 14 years.

HARVEY, M., L. DEVINE, 2007. Oceanographic conditions in the Estuary and the Gulf of St. Lawrence during 2006 : zooplankton ; Conditions océanographiques dans l’estuaire et le golfe du St-Laurent en 2006 : zooplancton. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2007/049, 40 p .

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Zooplankton biomass, abundance, and species composition in the Québec Region (Lower St. Lawrence Estuary [LSLE] and the Gulf of St. Lawrence) during 2006 are reviewed and compared to previous observations (1999-2005). In addition, this report gives an overview of the interannual variability in the mesozooplankton biomass and the macrozooplankton species composition, abundance, and biomass in the LSLE and the northwest Gulf of St. Lawrence (NWGSL) as measured in the fall of each year between 1994 and 2006. The state of the zooplankton at the three Québec fixed stations in 2006 was estimated as normal (zooplankton biomass, zooplankton total abundance, and copepod total abundance) and above normal (Calanus finmarchicus abundance) at Anticosti Gyre (AG), normal at Gaspé Current (GC), and normal (zooplankton biomass, zooplankton abundance, C. finmarchicus abundance) and lower than normal (copepod abundance) at Shediac Valley (SV). In addition, some changes in the zooplankton community structure were observed over the time series at AG and GC, including some changes in the rank of the top ten taxa and the appearance for the first time of some new taxa in the dominant species (top ten): Temora spp at GC and echinoderm larvae and larvacea at AG. Likewise, the zooplankton biomass along the seven Québec sections in 2006 was estimated as lower than normal along the Sept-Îles (TSI) and Bonne Bay (TBB) sections, normal along the Lower St. Lawrence Estuary (TESL) and the Centre Gulf of St. Lawrence (TCEN) sections, and above normal along the southwest Anticosti (TASO), Îles-de-la-Madeleine (TIDM), and Cabot Strait (TDC) sections. Concerning the total zooplankton abundance, anomalies were positive for all sections except along the Bonne Bay (TBB) section, where the total abundance of zooplankton was evaluated as normal. In addition, some changes in the zooplankton composition were observed over the time series in each region, including some changes in the rank order of the top ten taxa and the appearance of new taxa in the top ten species: Temora spp and Oncea sp in the LSLE; echinoderm larvae, larvacea, and Temora spp in the NWGSL; and Cladocera in Cabot Strait. The mean mesozooplankton biomass observed in November 2006 in the LSLE and NWGSL was 1.4 times lower than in 2005 and corresponds to the third lowest value observed over the last 13 years in the study area. Likewise, the mean macrozooplankton biomass decreased from 15.4 in 2005 to 5.9 ww g/m2 in 2006; this corresponds to the lowest value observed over the last 13 years. The most notable feature observed in the LSLE and NWGSL was that 2006 had the lowest mean biomass of euphausiids of the last 13 years due to a strong decrease in the abundance of Thysanoessa raschii, which was 4.3 times less abundant in 2006 than over the last 13 years. In addition, the mean abundance of the hyperiid amphipod Themisto libellula estimated in both regions in 2006 corresponds to the lowest value observed over the last 13 years.

HARVEY, M., J.-F. ST-PIERRE, L. DEVINE, A. GAGNÉ, Y. GAGNON, M.F. BEAULIEU, 2005. Oceanographic conditions in the Estuary and the Gulf of St. Lawrence during 2004 : zooplankton ; Conditions océanographiques dans l’estuaire et le golfe du St-Laurent en 2004 : zooplancton. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2005/043, 22 p .

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Zooplankton biomass, abundance, and species composition in the Québec Region (Lower St. Lawrence Estuary and Gulf of St. Lawrence) during 2004 are reviewed and related to conditions during the preceding years and over the longer term where applicable. In addition, this report gives an overview of the interannual variability of the mesozooplankton biomass and the macrozooplankton species composition, abundance, and biomass in the Lower Estuary (LE) and the northwest Gulf of St. Lawrence (NWGSL) as measured in fall of each year between 1994 and 2004. Even with only four zooplankton samples collected in February, March, June and November 2004, at both Québec fixed stations in 2004, we can see that the zooplankton biomass follow the same temporal variations pattern then during the 5 previous years (1999-2003). Furthermore, the zooplankton biomass observed in February, March, June and November were comparable to the one observed previously (1999-2003) at the same period of the year except in June and November in the Anticosti gyre were the zooplankton biomass was ca 2 times lower than normal. Hierarchical community analysis revealed that copepods continue to numerically dominate the zooplankton year-round at both Québec fixed station in 2004. The depth-integrated abundance of the different Calanus finmarchicus stages reveled that the reproductive success of C. finmarchicus seems to have been lower in 2004 than during the previous years at both fixed stations. The overall abundance and biomass of zooplankton observed in 2004 along all sections in spring and fall were comparable to observations made since 2000. The mean mesozooplankton biomass observed in November 2004 in the LE and the NWGSL was 1.3 times lower than in 2003 and corresponded to the second lowest value observed since the last 10 years in the study area. On the other hand, the mean macrozooplankton biomass observed in 2004 was 1.2 times higher than in 2003. The most notable feature observed in the LE and the NW GSL was that 2004 had the lowest mean biomass of euphausiids in the last decade and that for the first time the mean biomass of the hyperiid amphipod T. libellula was higher than the mean biomass of euphausiids. Finally, the mean abundance of both the chaetognaths and the jellyfish observed in 2004 corresponded to the highest value of the time series and were up 8.5 and 10.5 times higher than the average value of the last ten years respectively.

STARR, M., L. ST-AMAND, L. DEVINE, L. BÉRARD-THERRIAULT, P.S. GALBRAITH, 2004. State of phytoplankton in the Estuary and Gulf of St. Lawrence during 2003 ; État du phytoplancton dans l’estuaire et le golfe du Saint-Laurent en 2003. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2004/123, 35 p .

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We reviewed information concerning the seasonal and interannual variations in the concentrations of chlorophyll a, nitrates, and silicates as well as the abundance of the major species of phytoplankton measured at three fixed stations (Rimouski, Anticosti Gyre, and Gaspé Current) and six sections crossing the Estuary and Gulf of St. Lawrence. We concentrated on conditions prevailing in 2003 but also compared those observations with previous information from the 1992-2002 period. In 2003, the initiation of the major phytoplankton bloom at Station Rimouski in the Lower St. Lawrence Estuary occurred in late May, which is one month earlier than usual. Excluding 2002, this continued a trend that began in 1998. This major shift in the timing of the phytoplankton cycle is believed to be due to the below-normal spring freshwater runoff that has been generally observed in the St. Lawrence basin since 1998. The average phytoplankton biomass during spring-summer 2003 at Station Rimouski was also higher compared to 1992-1994, 1996, 1998, and 2000-2002, but lower compared to 1995, 1997, and, more especially, to 1999. Spring-summer phytoplankton production measured at this station was also much higher in 2003 compared to the previous three years but lower than in 1999. At the Anticosti Gyre and the Gaspé Current stations, nitrate and silicate concentrations were high in late fall-winter and low in late spring-summer due to biological consumption by phytoplankton. For both stations, the reduction of nutrients in the surface layer during spring-summer was much more pronounced in 2003 compared to the 2000-2002 period. Thus based on the evolution of nutrients, phytoplankton production in the northwestern Gulf of St. Lawrence could have been higher in 2003 compared to the previous three years. This is consistent with data from Station Rimouski in the Lower St. Lawrence Estuary. Similarly, the surface nutrient levels in late winter 2003 were also higher in the southern and northeastern Gulf of St. Lawrence compared to the previous two years while levels were not markedly different for the late spring-summer period. This suggests again that the spring phytoplankton bloom in these regions was also more intense in 2003 compared to recent years. For a third consecutive year, the analysis of the phytoplankton community composition in 2003 revealed the presence of the diatom Neodenticula seminae in many areas of the Gulf of St. Lawrence, with concentrations up to 197 X 102 cells per litre. This phenomenon is unusual since this species is typically found in North Pacific waters. In the Atlantic Ocean, this species has only been recorded in middle to high latitude Quaternary sediments, dating from between 0.84 and 1.2 million years ago. It is proposed that this Pacific species was introduced naturally into the Gulf (across the Arctic, down the Labrador Current, and through Strait of Belle Isle) rather than via ballast waters. The invasion of N. seminae on the Atlantic coast is consistent with recent observations suggesting a greater influx of Pacific waters into the Atlantic.

HARVEY, M., J.-F. ST-PIERRE, L. DEVINE, A. GAGNÉ, Y. GAGNON, M.F. BEAULIEU, 2004. Oceanographic conditions in the Estuary and the Gulf of St. Lawrence during 2003: zooplankton ; Conditions océanographiques dans l’estuaire et le golfe Saint-Laurent en 2003: zooplancton. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2004/061, 31 p .

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Zooplankton biomass, abundance, and species composition in the Québec Region (Lower St. Lawrence Estuary and Gulf of St. Lawrence) during 2003 are reviewed and related to conditions during the preceding years and over the longer term where applicable. In addition, this report gives an overview of the interannual variability of the mesozooplankton biomass and the macrozooplankton species composition, abundance, and biomass in the Lower Estuary and the northwest Gulf of St. Lawrence as measured in September of each year between 1994 and 2003. The zooplankton biomass and abundance at the Québec fixed stations in 2003 were slightly higher than observations made in 2000, 2001, and 2002 at both stations. The relative proportion of copepods vs. the other groups of mesozooplankton increased from 70 to 95 % between 1999 and 2003 in the Gaspé Current (GC) and from 70 to 85 % between 1999 and 2001 in the Anticosti Gyre (AG). No larvacea were found at both fixed stations in 2003. The depth-integrated abundance of the Calanus finmarchicus stage composition showed that there were two periods of reproduction for this species at both stations in 2003. Reproduction occurred in summer (June-July) and fall (September-October) and was synchronized at both stations. The same situation was observed in 2000, 2001, and 2002. In 2003, the abundance of Calanus finmarchicus reached record high level since 1999 at both fixed stations (GC and AG). The zooplankton biomasses and abundances observed in early spring, late spring, and fall 2003 along the six AZMP sections were comparable to observations made in 2002, 2001, and 2000. The mesozooplankton biomass in the Lower Estuary and the northwest Gulf of St. Lawrence in 2003 was slightly higher than in 2002 while the macrozooplankton biomass was comparable to the 2002 level. The year 2003 was characterized by a significant increase in the mean abundance of the pelagic amphipod Themisto libellula and the mysid Boreomysis arctica and a significant decrease in the mean abundance of the chaetognath Sagitta elegans and the gelatinous zooplankton Aglantha digitale, Obelia spp., and Boreo spp. The significant relationships between the mean annual abundance of the hyperiid amphipod T. libellula and the percentage of Labrador Shelf water supported the hypothesis that the significant increase in the mean abundance of this species observed in 2001, 2002, and 2003 in the Lower Estuary and the Gulf of St. Lawrence is associated with the intrusion of the cold Labrador Shelf water into the Gulf of St. Lawrence via the Strait of Belle Isle (Harvey et al 2003).

STARR, M., L. ST-AMAND, L. DEVINE, L. BÉRARD-THERRIAULT, 2003. State of phytoplankton in the Estuary and Gulf of St. Lawrence during 2002 ; État du phytoplancton dans l'estuaire et le golfe du St-Laurent en 2002. DFO, Canadian Science Advisory Secretariat, Research Document ; MPO, Secrétariat canadien de consultation scientifique, Document de recherche, 2003/103, 29 p .

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Information concerning the seasonal and interannual variations in the concentrations of chlorophyll a, nitrates, and silicates as well as the abundance of the major species of phytoplankton measured from three fixed stations (Rimouski, Anticosti Gyre and Gaspé Current) and six sections crossing the Estuary and Gulf of St. Lawrence was reviewed. The authors concentrated on conditions prevailing in 2002 but also compared those observations with previous information from the 1992-2001 period. In 2002, the initiation of the major phytoplankton bloom at Station Rimouski in the Lower St. Lawrence Estuary occurred in late June, which is near the historical mean date. This contrasts with observations made from 1998 to 2001, when the spring phytoplankton bloom began 6-8 weeks earlier than normal (mid to early May). The average phytoplankton biomass during spring-summer 2002 at Station Rimouski was also somewhat higher compared to 1992-1994, 1998, and 2000-2001, but much lower compared to 1995, 1997, and, more especially, to 1999. In the Anticosti Gyre and the Gaspé Current, the depletion of nutrients in the surface layer (0-50 m) during spring occurred later in 2002 compared to the 1996-2001 period, suggesting that phytoplankton growth was also initiated later in 2002 compared to recent years in the northwestern part of the Gulf of St. Lawrence. This was particularly true for the Gaspé Current. The reduction of nutrients in the surface layer during spring-summer was also somewhat more pronounced in 2002 compared to the 2000-2001 period but much less compared to 1999. Thus based on the evolution of nutrients, phytoplankton production in the northwestern Gulf of St. Lawrence could have been higher in 2002 compared to the previous two years but much lower than for 1999. This is consistent with data from Station Rimouski in the Lower St. Lawrence Estuary. For a second consecutive year, the analysis of community composition in 2002 revealed the massive presence of the diatom Neodenticula seminae in most areas of the Gulf of St. Lawrence, with concentrations up to 1 x 106 cells per litre. This phenomenon is unusual since this species is usually found in North Pacific waters. In the Atlantic Ocean, this species has only been recorded in middle to high latitude Quaternary sediments, dating from between 0.84 and 1.2 million years ago. It is proposed that this Pacific species was introduced naturally into the Gulf (across the Arctic, down the Labrador Current, and through Strait of Belle Isle) rather than via ballast waters. The return of N. seminae to the Atlantic coast is consistent with recent observations indicating a greater influx of Pacific waters into the Atlantic and the freshening of the North Atlantic waters. In late spring and early fall 2002, the chlorophyll levels were higher in the southern Gulf of St. Lawrence compared to the previous three years. In the eastern part of the Gulf, the chlorophyll and nitrate levels in the surface layer in late spring and fall 2002 were not notably different from those observed in 1999-2001.

FUENTES-YACO, C., A.F. VÉZINA, T. PLATT, W.G. HARRISON, P.G. CORMIER, L.E. WAITE, L. DEVINE, 1998. Spatio-temporal distribution of phytoplankton pigments in Northumberland Strait : CZCS imagery and in situ data. Can. Tech. Rep. Hydrogr. Ocean Sci., 195, 37 p .

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This report describes the spatial and seasonal variations of phytoplankton pigments in the southern Gulf of St. Lawrence using Coastal Zone Color Scanner (CZCS) images and in situ data collected during different periods. To compare the patterns obtained with both methods, the CZCS and in situ data were grouped into regional subdivisions and computed averages. Because there are no climatological standards for biological and chemical data to compare with this information, subdivisions were developed for commercial fisheries (International Commission for Northwest Atlantic Fisheries [ICNAF/NAFO]) and physical oceanographic features (Petrie et al., 1996) as first attempts. Finally, we used new subareas based on visual analyses of satellite phytoplankton pigment imagery. Both the satellite and in situ data sets show similar synoptic patterns in the spatial distribution of phytoplankton pigments; however, the CZCS estimate gives a more detailed view, suggesting five subareas. The pigment concentrations evaluated in these subareas seemed to vary temporally in agreement with in situ measurements, showing a bi-modal cycle with high and comparable pigment levels during both spring and late summer - early fall. In conclusion, we recommend : i) the study of possible links between in situ biological (phytoplankton biomass), physical, and nutrient data within the subareas identified using CZCS-derived phytoplankton pigment levels; ii) the confirmation or modification of the proposed regionalization using remote sensing data from new satellites like the SeaWIFS and with sensors of higher spatial resolution (CASI); and iii) that the grid stations in future research missions be modified to adequately sample the different subareas identified using CZCS images.

GILBERT, D., A.F. VÉZINA, B. PETTIGREW, D.P. SWAIN, P.S. GALBRAITH, L. DEVINE, N. ROY, 1997. État du golfe du Saint-Laurent : conditions océanographiques en 1995. Rapp. tech. can. hydrogr. sci. océan., 191, 113 p .

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We present an overview of the oceanographic conditions in the Gulf of St. Lawrence for 1995. The highlights are that 1) winter air temperatures were near normal in the western Gulf, but were close to 2 °C below normal in the eastern Gulf; 2) the summer was warm and dry in the western Gulf; 3) the ice cover was slightly above normal, with more severe ice conditions in the northeastern Gulf than in the western Gulf; 4) the core temperature of the cold intermediate layer was colder than normal; 5) the bottom area with a temperature below 0 °C reached a record high in the southern Gulf; 6) the deep layers cooled relative to 1994, and the cooling was more intense in he 100-200 m layer (O.9 °C) than in the 200-300m layer (0.3 °C); 7) the dissolved oxygen content of the 200-300 m layer was slightly below the 1981-1995 average in the Cabot Strait and Honguedo Strait sections; 8) the distribution of chlorophyll and nitrate in the surface layer corresponded roughly with the patterns inferred from historical data, i.e. a gradient of decreasing biomass from the West and south towards the east and north that is strongly inversely correlated with salinity; 9) in Northumberland Strait, the concentrations of chlorophyll near the bottom were much higher than elsewhere.

DEVINE, L., C. SAVENKOFF, A.F. VÉZINA, J.-P. CHANUT, S. ROY, L. COMEAU, V. DUBÉ, D. BLASCO, Y. GRATTON, 1997. Compilation des données biologiques et chimiques dans l'estuaire maritime du Saint-Laurent : programme COUPPB 1989, 1990 et 1991. Rapp. stat. can. hydrogr. sci. océan., 150, 103 p .

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To better understand the physical-biological interactions regulating carbon flows in the Lower St. Lawrence Estuary (LSLE), a multidisciplinary program known as COUPPB (COUplage des Processus Physiques et Biogéochimiques; Mesoscale Physical-Biogeochemical Coupling) was carried out in the LSLE from June 1989 to July 1991. This report presents the stations sampled and the variables measured during the five missions. The objective of the first two missions (COUPPB89 : June-July 1989; COUPPB90-1 : June-July 1990) was to extensively sample the area to resolve the mesoscale variations (10-20 km, 5-10 days). The subsequent missions were planned, based on the data from these first missions, to examine the relationships between the different physical, chemical, and biological variables at stations characterized by strongly contrasting hydrodynamic conditions (COUPPB90-2 : September 1990; COUPPB91-1 : May 1991 : COUPPB91-2 : July 1991).

VÉZINA, A.F., S. DEMERS, I. LAURION, T. SIME-NGANDO, S. KIM JUNIPER, L. DEVINE, 1997. Carbon flows through the microbial food web of first-year ice in Resolute Passage (Canadian High Arctic). J. Mar. Syst., 11: 173-189 .

GODBOUT, L., D. DOBSON, G. MOREAULT, L. DEVINE, 1995. Suspended and sedimented matter at a fixed station near Gascons, baie des Chaleurs, Québec. Can. Tech. Rep. Fish. Aquat. Sci., 2058, 42 p .

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Water column constituents and sedimentation rates of C, N, and pigments were measured at a fixed station near Gascons (26 m) in baie des Chaleurs, Québec, at 1-4 day intervals between 16 June and 20 August 1992. Water column constituents were chlorophyll a and phaeopigments (<5 pm, 5-153 pm, 0.7-153 pm) and particulate organic carbon and nitrogen. Constituents in the water column and in the sedimentation varied little throughout the sampling period (CV 40 %) except for water column chlorophyll a >5 pm and phaeopigments >5 pm (CV >117 %) and sedimented chlorophyll a (CV=92 %). The standing stock of chlorophyll a in the size class >5 pm was positively related to the standing stock of total chlorophyll a. This log-log mode1 had a slope of 2.25 and explained 86.5 % of the variation. Empirical models describing the sedimentation rate of pigments (R2=41.0-46.4 %) had higher predictive power than those predicting the sedimentation rates of either C (R2=1 1.5 %-14.6 %) or N (R2=20.2 %-24.2 %). The best predictor of the sedimentation rate of pigments was the standing stock of pigment in the size class >5 pm (R2=46.4 %). The slope of the log-log relationship (0.41) implied that the sedimentation rate did not increase linearly with the standing stock of pigment >5 pm. Inferences from these models and their implications on the monitoring of baie des Chaleurs are discussed.

VÉZINA, A.F., Y. GRATTON, N. NAVARRO, L. DEVINE CASTONGUAY, 1994. Structure thermohaline et biologique de la couche de surface de l'estuaire maritime du Saint-Laurent. II, Juin-juillet 1990. Rapp. stat. can. sci. halieut. aquat., 894(2), 79 p .

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This report presents the vertical profiles of temperature, salinity, in vivo fluorescence, and nitrate concentration that were obtained during a series of oceanographic missions conducting high-resolution sampling in the lower St. Lawrence Estuary between 29 June and 9 July 1990. The 157 profiles that were retained following scrutiny of the data were reduced to six major modes of variation by the method of empirical orthogonal functions. The first three modes, which explain more than 55 % of the total variation, are mapped and show the progression of the dramatic changes in the physical and biological structure taking place between cruises separated by not more than one week. The variations on a quasi-synoptic scale were even more important than anticipated; the processes responsible for these variations will be the subject of future studies.

VÉZINA, A.F., P. VINET, L.D. CASTONGUAY, 1992. Structure thermohaline et biologique de la couche de surface de l'estuaire maritime du Saint-Laurent. I, Juin-juillet 1989. Rapp. stat. can. sci. halieut. aquat., 894(1), 25 p .

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This report presents the vertical profiles of temperature, salinity, in vivo fluorescence, and nitrate concentration that were obtained during a series of cruises conducting high-resolution sampling in the lower St. Lawrence Estuary between 19 June and 14 July 1989. The 255 profiles that were kept following scrutiny of the data were reduced to six major modes of variation by the method of empirical orthogonal functions. The first three modes, which explain more than 55 % of the total variation, are mapped and show the progression of the dramatic changes in the physical and biological structure taking place between cruises separated by not more than one week. The variation on a quasi-synoptic scale were even more important than was anticipated, and the processes responsible for these variations have not yet been elucidated.