(Table 2) Lipid fluxes derived from sediment trap samples

Phytoplankton is a sentinel of marine ecosystem change. Composed by many species with different life-history strategies, it rapidly responds to environment changes. An analysis of the abundance of 54 phytoplankton species in Galicia (NW Spain) between 1989 and 2008 to determine the main components of temporal variability in relation to climate and upwelling showed that most of this variability was stochastic, as seasonality and long term trends contributed to relatively small fractions of the series. In general, trends appeared as non linear, and species clustered in 4 groups according to the trend pattern but there was no defined pattern for diatoms, dinoflagellates or other groups. While, in general, total abundance increased, no clear trend was found for 23 species, 14 species decreased, 4 species increased during the early 1990s, and only 13 species showed a general increase through the series. In contrast, series of local environmental conditions (temperature, stratification, nutrients) and climate-related variables (atmospheric pressure indices, upwelling winds) showed a high fraction of their variability in deterministic seasonality and trends. As a result, each species responded independently to environmental and climate variability, measured by generalized additive models. Most species showed a positive relationship with nutrient concentrations but only a few showed a direct relationship with stratification and upwelling. Climate variables had only measurable effects on some species but no common response emerged. Because its adaptation to frequent disturbances, phytoplankton communities in upwelling ecosystems appear less sensitive to changes in regional climate than other communities characterized by short and well defined productive periods.

The response of surf-zone phytoplankton to nutrient enrichment (Cassino Beach, Brazil)

To understand the mechanisms that trigger changes in chlorophyll a and species composition in the phytoplankton of the surf-zone at Cassino Beach (RS), we performed two short nutrient-enrichment experiments (4–5 days each) during the summer and winter of 2010. Seawater was incubated under controlled conditions of temperature (summer 25± 3 °C, winter 18±1 °C), salinity (summer 28, winter 26) and irradiance (100 μmol m−2 s−1 ). Dissolved inorganic nutrients were added in various concentrations in the summer (silicate, Si; nitrate, N; phosphate, P) and winter (N, P) experiments. Samples were taken daily for cell counts and chlorophyll a analysis. In both experiments, chlorophyll a values and cell density showed a significant increase (mainly diatoms) in the treatments with nitrate addition, regardless of the proportion added. In the summer experiment, the largest chlorophyll a increase, approximately threefold (31.5 to 89.5 μg L−1 ), was observed in the NP treatment due to the growth of Asterionellopsis glacialis (Castracane) Round, Skeletonema tropicum Cleve, Thalassiosira sp. Cleve and Pseudo-nitzschia spp. Peragallo. The maximum growth was obtained in the SiNP treatment for S. tropicum (μ=0.7), Thalassiosira (μ= 1.9) and Pseudo-nitzschia (μ= 1.3) and in the SiN treatment for A. glacialis (μ= 1.0). In the winter experiment, the chlorophyll a content increased 4.2 and 5.5 times, respectively, in the N and NP treatments (maxima 38.8 μg L−1 and 31.5 μg L−1 ), where A. glacialis (μ= 1.7–1.9) and Cylindrotheca closterium (Ehrenberg) Reimann & J.C. Lewin (μ= 1.0–1.96) showed the highest amount of growth. These results indicate that nitrate is the most important nutrient controlling phytoplankton chlorophyll a at sandy Cassino Beach. However, the responses of different species to enrichment during the summer and winter indicated that other factors also played a role. A. glacialis, present during both seasons, presented the highest growth rate during the winter, whereas during the summer it was independent of nutrient enrichment but coincided with the lowest growth of S. tropicum. This finding suggested the occurrence of allelopathic interactions between these species. During the summer, multi-enrichment (SiNP) favoured the best growth of S. tropicum, Pseudo-nitzschia spp. and Thalassiosira sp. These results indicated that the phytoplankton composition and diversity in the surf zone of Cassino Beach are shaped by the availability of silicate and phosphorus as well as by the availability of nitrate.

The rediscovery of the Cladoceran Eurycercus glacialis Lilljeborg, 1887 (Branchiopoda, Chydoridae) in Scotland

The author describes an investigation, the primary aims of which were to locate accurately and assess the ecological status of two Eurycercus glacialis populations in Scotland. A 1957 record of the species did not give a precise location, and on publication of a preliminary report on the location, the possibility of a second location was suggested. In April and May 1988, 16 waterbodies were sampled near Tain, in Scotland, as a result of which the dune waterbodies at Morrich More have now been positively identified as the only known location of E. glacialis in mainland Britain. A second population was found on Shetland. As the mainland site is under considerable developmental pressure from oil pipeline construction, the importance of determining the extent of the distribution on Shetland is highlighted.

Spatial and temporal distribution of North Atlantic right whales (Eubalaena glacialis) in Cape Cod Bay, and implications for management

Cape Cod Bay (Massachusetts) is the only known winter and early spring feeding area for concentrations of the endangered North Atlantic right whale (Eubalaena glacialis) population. During January–May, 1998–2002, 167 aerial surveys were conducted (66,466 km of total survey effort), providing a complete representation of the spatiotemporal distribution of right whales in the bay during winter and spring. A total of 1553 right whales were sighted; some of these sightings were multiple sightings of the same individuals. Right whale distribution and relative abundance patterns were quantified as sightings per unit of effort (SPUE) and partitioned into 103 23-km2 cells and 12 2-week periods. Significant interannual variations in mean SPUE and timing of SPUE maxima were likely due to physically forced changes in available food resources. The area of greatest SPUE expanded and contracted during the season but its center remained in the eastern bay. Most cells with SPUE>0 were inside the federal critical habitat (CH) and this finding gave evidence of the need for management measures within CH boundaries to reduce anthropogenic mortality from vessel strikes and entanglement. There was significant within-season SPUE variability: low in December−January, increasing to a maximum in late February−early April, and declining to zero in May; and these results provide support for management measures from 1 January

History of Whaling and Estimated Kill of Right Whales, Balaena glacialis, in the Northeastern United States, 1620–1924

This study, part of a broader investigation of the history of exploitation of right whales, Balaena glacialis, in the western North Atlantic, emphasizes U.S. shore whaling from Maine to Delaware (from lat. 45°N to 38°30'N) in the period 1620–1924. Our broader study of the entire catch history is intended to provide an empirical basis for assessing past distribution and abundance of this whale population. Shore whaling may have begun at Cape Cod, Mass., in the 1620’s or 1630’s; it was certainly underway there by 1668. Right whale catches in New England waters peaked before 1725, and shore whaling at Cape Cod, Martha’s Vineyard, and Nantucket continued to decline through the rest of the 18th century. Right whales continued to be taken opportunistically in Massachusetts, however, until the early 20th century. They were hunted in Narragansett Bay, R.I., as early as 1662, and desultory whaling continued in Rhode Island until at least 1828. Shore whaling in Connecticut may have begun in the middle 1600’s, continuing there until at least 1718. Long Island shore whaling spanned the period 1650–1924. From its Dutch origins in the 1630’s, a persistent shore whaling enterprise developed in Delaware Bay and along the New Jersey shore. Although this activity was most profi table in New Jersey in the early 1700’s, it continued there until at least the 1820’s. Whaling in all areas of the northeastern United States was seasonal, with most catches in the winter and spring. Historically, right whales appear to have been essentially absent from coastal waters south of Maine during the summer and autumn. Based on documented references to specific whale kills, about 750–950 right whales were taken between Maine and Delaware, from 1620 to 1924. Using production statistics in British customs records, the estimated total secured catch of right whales in New England, New York, and Pennsylvania between 1696 and 1734 was 3,839 whales based on oil and 2,049 based on baleen. After adjusting these totals for hunting loss (loss-rate correction factor = 1.2), we estimate that 4,607 (oil) or 2,459 (baleen) right whales were removed from the stock in this region during the 38-year period 1696–1734. A cumulative catch estimate of the stock’s size in 1724 is 1,100–1,200. Although recent evidence of occurrence and movements suggests that right whales continue to use their traditional migratory corridor along the U.S. east coast, the catch history indicates that this stock was much larger in the 1600’s and early 1700’s than it is today. Right whale hunting in the eastern United States ended by the early 1900’s, and the species has been protected throughout the North Atlantic since the mid 1930’s. Among the possible reasons for the relatively slow stock recovery are: the very small number of whales that survived the whaling era to become founders, a decline in environmental carrying capacity, and, especially in recent decades, mortality from ship strikes and entanglement in fishing gear.

Using the Continuous Plankton Recorder to investigate the absence of North Atlantic right whales (Eubalaena glacialis) from the Roseway Basin foraging ground

North Atlantic right whales (Eubalaena glacialis) were absent from Roseway Basin, located off southeastern Nova Scotia, for a 7-year period (1993–1999). The objective of this study was to examine the availability of the right whale's main prey, Calanus finmarchicus, in Roseway Basin during those 7 years to determine if the whales’ absence was due to inadequate prey resources. Since we had no historical data on zooplankton abundances at depth on the Scotian Shelf, near-surface zooplankton abundance data from the Continuous Plankton Recorder were used to infer water-column abundances. In addition, environmental parameters that are often correlated with high zooplankton concentrations were examined. The hypotheses tested were that changes in these parameters would be detectable between three time periods: pre-1993, 1993–1999 and post-1999. Calanus finmarchicus abundance was found to be lowest during 1993–1999, suggesting that right whales were not foraging in Roseway Basin because of the near-absence of their main prey species. Decreased in situ salinity and density proved to be indicators of the changes in circulation in the 1990s that may have affected the advection of C. finmarchicus onto the Scotian Shelf.

Live discrimination of Calanus glacialis and C. finmarchicus females: can we trust phenological differences?

Two key players in the Arctic and subarctic marine ecosystem are the calanoid copepods, Calanus finmarchicus and C. glacialis. Although morphologically very similar, these sibling species have different life cycles and roles in the Arctic pelagic marine ecosystem. Considering that the distribution of C. glacialis corresponds to Arctic water masses and C. finmarchicus to Atlantic water masses, the species are frequently used as climate indicators. Consequently, correct identification of the two species is essential if we want to understand climate-impacted changes on Calanus-dominated marine ecosystems such as the Arctic. Here, we present a novel morphological character (redness) to distinguish live females of C. glacialis and C. finmarchicus and compare it to morphological (prosome length) and genetic identification. The characters are tested on 300 live females of C. glacialis and C. finmarchicus from Disko Bay, western Greenland. Our analysis confirms that length cannot be used as a stand-alone criterion for separation. The results based on the new morphological character were verified genetically using a single mitochondrial marker (16S) and nuclear loci (six microsatellites and 12 InDels). The pigmentation criterion was also used on individuals (n = 89) from Young Sound fjord, northeast Greenland to determine whether the technique was viable in different geographical locations. Genetic markers based on mitochondrial and nuclear loci were corroborative in their identification of individuals and revealed no hybrids. Molecular identification confirmed that live females of the two species from Greenlandic waters, both East and West, can easily be separated by the red pigmentation of the antenna and somites of C. glacialis in contrast to the pale opaque antenna and somites of C. finmarchicus, confirming that the pigmentation criterion is valid for separation of the two species

Contrasting transcriptome response to thermal stress in two key zooplankton species, Calanus finmarchicus and C. glacialis

Climate change has already led to the range expansion of warm-water plankton assemblages in the northeast Atlantic and the corresponding range contraction of colder-water species. The temperate copepod Calanus finmarchicus is predicted to shift farther northward into polar waters traditionally dominated by the arctic copepod C. glacialis. To identify temperaturemediated changes in gene expression that may be critical for the thermal acclimation and resilience of the 2 Calanus spp., we conducted a whole transcriptome profiling using RNA-seq on an Ion Torrent platform. Transcriptome responses of C. finmarchicus and C. glacialis from Disko Bay, west Greenland, were investigated under realistic thermal stresses (at + 5, +10 and +15°C) for 4 h and 6 d. C. finmarchicus showed a strong response to temperature and duration of stress, involving up-regulation of genes related to protein folding, transcription, translation and metabolism. In sharp contrast, C. glacialis displayed only low-magnitude changes in gene expression in response to temperature and duration of stress. Differences in the thermal responses of the 2 species, particularly the lack of thermal stress response in C. glacialis, are in line with laboratory and field observations and suggest a vulnerability of C. glacialis to climate change.

Tonnacypris glacialis (Ostracoda, Cyprididae):taxonomic position, (palaeo)ecology, and zoogeography

The freshwater ostracod Tonnacypris glaciallis (Sars, 1890) is reported from the European Pleistocene for the first time. The historical allocation of the species is discussed, and the species composition and characteristics of Tonnacypris is Diebel & Pietrzeniuk (1975) and its phylozoogeography are considered. The significance of T. glacialis is reviewed, particularly from the viewpoint of the possible implications of parthenogenesis (and occasional-male production) for the Quaternary history of the genus, and for the use of the species in palaeoenvironmental reconstruction. It is suggested that the Pleistocene fossil occurrence of I: glacialis in modern temperate latitudes is a robust indicator of mean summer temperatures of 6 degrees C.

Role of food availability in the bathymetric distribution of the starfish "Marthasterias glacialis" (Lamk.) on reefs of northern Portugal

[EN] We examined whether the abundance and size of the starfish Marthasterias glacialis (Lamk.) exhibit a depth-dependent partitioning on subtidal reefs. We tested the hypothesis that differences in food availability can result in habitat partitioning along a depth gradient. The abundance and size of M. glacialis was registered at 4 depth strata: 0-4 m, 4-8 m, 8-12 m, and >12 m; we also recorded the number of food items that they were preying on. The abundance and size of M. glacialis decreased with depth. Mussels (Mytilus galloprivincialis) were the most preyed food item across all depth strata, followed by gastropods, sea urchins and barnacles; M. glacialis also consumed a significantly larger amount of mussels in feeding experiments compared with sea urchins and gastropods. The abundance of M. galloprivincialis beds decreased with depth. The clear link between the decrease in abundance and size of M. glacialis with depth and the decay of the most consumed prey (mussels) suggest that food availability may play an important role in the vertical distribution of this starfish, though wave-associated turbulence in the first few metres of the subtidal could also limit the abundance of M. glacialis.