Western Baffin Bay Research Articles

Late Quaternary paleoceanography of the western Baffin Bay region: evidence from fossil diatoms

Seven marine cores from the east coast of Baffin Island were examined for variations in diatom content. The cores have good age control and were used for Holocene paleoceanographic reconstruction. A diatom barren zone or a zone of much reduced diatom productivity is evident some time during the early to middle Holocene. This zone ends earlier in the southern area than farther north. The changes in diatom productivity may be caused by changing oceanographic variables such as sea ice extent and the presence of a meltwater cap during deglaciation. Light isotope 18O events ("meltwater spikes") generally coincide with barren or reduced productivity zones in the cores from the middle and southern part of the shelf and from Jones Sound, suggesting a general surficial cooling of the fjord and ocean water. If diatom productivity was depressed because of a meltwater cap over the core sites with increasing sea ice extent, the theory of a general "marine optimum" in all of Baffin Bay and Davis Strait from 8000 to 6000 BP may have to be modified.

Late quaternary spatial and temporal changes in clay- and silt-size mineral assemblages of fiord and shelf cores, western Baffin Bay, northwest North Atlantic

Clay- and silt-size mineral assemblages are described from eight piston cores from the fiords and shelf on the western margin of Baffin Bay, Arctic Canada. Radiocarbon dates indicate that all the cores extend back in time to the last local glacial/interglacial transition (i.e. 8–10 ka); four extend back to between 10 and 12 ka, and HU77-021-156, located on the Southeast Baffin Island shelf, includes the entire late Foxe glacial stage. Silt- and clay-size particles constitute ca 40 and 55%, respectively, by weight of the bulk sediment. The clay-size fraction is dominated by mica; feldspars and quartz are the main constituents of the silt fraction. The fiord sediments are mainly composed of local mineralogies, but on the shelf, and at times in the fiords, exotic mineral species occur. The most important of these are detrital carbonates, derived from erosion of the Paleozoic basins in Arctic Canada and/or northwest Greenland. Both calcite and dolomite occur; calcite is the major carbonate mineral in the “southern” cores, whereas dolomite is the most abundant in cores north of 66°N. Higher inputs of carbonate species occur during regional deglaciation, 7–10 ka, and during the last 5 ka (probably reflecting increased iceberg production from northwest Greenland). Thus variations in the precentages of the carbonate minerals indicate significant shifts in Late Quaternary glacial-sediment source areas and oceanographic regimes.

Feeding, Respiration and Excretion of the Copepod <i>Calanus hyperboreus</i> from Baffin Bay, Including Waters Contaminated by Oil Seeps

Metabolic processes in eastern arctic copepods Calanus hyperboreus were analyzed during the post-bloom period (August-September). Mixed adult and subadult copepods were collected from 12 stations in Baffin Bay (Davis Strait to Lancaster Sound) by trawling from 0-300 m. Measurements were made of clearance rate, O2-consumption and NH3 excretion. The cruise track included 6 stations in oil-seep contaminated waters of Scott Inlet and Buchan Gulf. Physiological parameters for populations of C. hyperboreus from the latter stations were compared with those from non-seep stations. Mean O2 consumption rates (0.309 - 0.907 µl O2 / mg dry wt / h) for all stations were similar to those described for Antarctic calanoid species but were higher than reported for more northern arctic waters. Mean ammonia excretion rates (0.023 - 0.071 µg N / mg dry wt / h) were somewhat lower than reported for comparable Antarctic species and were similar to values from other eastern arctic studies. O:N ratios for 11 of the 12 stations occupied ranged between 8.4 and 22.1, indicative of protein-based metabolism. The single exception was a High Arctic station with O:N ratio 43.6. Clearance rates were low to nonexistant for all stations. Most of the non-feeding values came from the Scott Inlet-Buchan Gulf region of western Baffin Bay. At those stations in this region a strong negative correlation (P<.01) exists between clearance rate and hydrocarbon contamination. This suggests that in the oil-seep region of Baffin Bay feeding may be suppressed in Calanus hyperboreus by low concentrations of petroleum hydrocarbons derived from sub-sea seepage.Key words: zooplankton, Calanus hyperboreus, Arctic, metabolism, oil seep, petroleum, hydrocarbons, oil pollution

The Dovekie, <i>Alle alle</i>, as a Spring Migrant in Eastern Lancaster Sound and Western Baffin Bay

The distribution and numbers of dovekies during spring migration were studied by aerial surveys of eastern Lancaster Sound (1976, 1978, 1979) and western Baffin Bay (1978, 1979). Dovekies that nest in northwest Greenland migrated north through the study area during May. Extrapolations of recorded densities indicate that a peak of ~14 million dovekies may have been present in eastern Lancaster Sound and northwest Baffin Bay in mid-May 1978: fewer were present in May 1979, although the migration was more protracted and total numbers migrating through these areas may have been similar. Dovekies preferred offshore pack ice habitats with moderate to heavy ice cover. Possible reasons for the highly variable distributions in the three years are discussed.Key words: dovekie, Alle alle, spring migration, Lancaster Sound, Baffin Bay, aerial surveys

Ivory Gull (<i>Pagophila eburnea</i>) Distribution in Late Summer and Autumn in Eastern Lancaster Sound and Western Baffin Bay

Ivory gulls in western Baffin Bay and eastern Lancaster Sound were studied in 1976, 1978 and 1979 using aerial surveys. During September and October concentrations of hundreds of ivory gulls occurred along glacier fronts on southeast Ellesmere and northeast and southeast Devon islands, and where offal was available near the settlements of Grise Fiord and Pond Inlet. Dispersal (= southward migration) from coastal to offshore areas proceeded as pan ice cover increased in offshore areas, usually in late September or early October in Lancaster Sound and in mid-October in Baffin Bay east of Baffin Island. Lancaster Sound and northwest Baffin Bay may be a major autumn migration route for ivory gulls that breed in the central and eastern High Arctic and winter in southern Davis Strait and areas to the south.Key words: ivory gull, Pagophila eburnea, autumn status, migration, Baffin Bay, Lancaster Sound, glacier fronts, aeriel surveys

Spring Migration and Habitat Use by Seabirds in Eastern Lancaster Sound and Western Baffin Bay

The status and distribution, during spring and early summer, of northern fulmars (Fulmarus glacialis), black-legged kittiwakes (Rissa tridactyla), thick-billed murres (Uria lomvia) and black guillemots (Cepphus grylle) were studied during aerial surveys in eastern Lancaster Sound (1976, 1978, 1979) and western Baffin Bay (1978, 1979). Fulmars were present in the study area by early May but most undertook a pre-laying exodus in late May before returning in early June to nest. During June and the first half of July, they were common along coasts and in offshore areas throughout the region. Kittiwakes returned in late May and numbers increased through June, both along coasts and offshore. Numbers offshore decreased after nesting, which begins in mid- to late June. Murres returned to the study area around mid-May and were abundant during June, especially near their colonies. Densities were generally highest along fast ice edges. Guillemots returned to the study area in the last half of May and were widespread along coasts, ice edges and in offshore areas during June. Densities were much lower after nesting, which commences in late June. Densities of fulmars, murres and guillemots were much higher along fast ice edges than along ice-free coasts: the opposite was true of kittiwakes. Offshore, fulmars and kittiwakes preferred waters with little or no pack ice, whereas murres and guillemots preferred moderate to heavy pack ice. These habitat preferences affected the distributions of the species within the region. Ice conditions in eastern Lancaster Sound were markedly different during each of the three years of study. Effects of different ice conditions on the species' distributions are assessed. Seabird distributions in six parts of the region are summarized.Key words: fulmar, kittiwake, murre, guillemot, distribution, habitat use, Lancaster Sound, Baffin Bay

Pelagic feeding ecology of dovekies, Alle alle, in Lancaster Sound and western Baffin bay : Bradstreet, M.S.W., 1982. Arctic, 35(1): 126–140

Pelagic feeding ecology of dovekies, Alle alle, in Lancaster Sound and western Baffin bay : Bradstreet, M.S.W., 1982. Arctic, 35(1): 126–140

Major Features of the Summer Near-Surface Circulation of Western Baffin Bay, 1978 and 1979

In the summers of 1978 and 1979, an extensive physical oceanographic program was carried out in western Baffin Bay and Lancaster Sound. Data collected include satellite-tracked drifter measurements, CTD profiles and time series of subsurface currents. They indicate that the near-surface circulation of the area is dominated by the southward-flowing Baffin Current. This current, observed to extend at least as far north as Lady Ann Strait (76° N) and south to Cape Dyer (67° N), is largely confined to within 100 km of the coastline. It varies in both intensity and width with the strongest flows occurring where the current follows a cyclonic intrusion into and out of eastern Lancaster Sound; here in the core of the current the median near-surface (4 to 11 m) speeds are 75 cm/s, decreasing to 50 cm/s at 40 m depth and 25 cm/s at 250 m depth. To the east of Devon, Bylot and Baffin islands, the current is well-defined, but generally less intense with typical near-surface speeds of 30 cm/s. Important spatial variations occurred in the circulation of the area. In eastern Lancaster Sound, two distinct and alternating flow patterns were observed in the strong intrusive current in the summer of 1979. Transient large-scale meanders of the circulation were detected in the offshore portion of the Baffin Current off the east coasts of Bylot and Baffin islands. Between the eastern coastline of Bylot Island and the core of the southeasterly flowing Baffin Current, anticyclonic eddies of approximately 20 km diameter occasionally occurred.Key words: Baffin Bay, Baffin Current, circulation, Lancaster Sound, oceanography, surface currents, sub-surface currents

Spring migration and habitat use by seabirds in eastern Lancaster Sound and western Baffin Bay : McLaren, P.L., 1982. Arctic, 35(1):88–111

Spring migration and habitat use by seabirds in eastern Lancaster Sound and western Baffin Bay : McLaren, P.L., 1982. Arctic, 35(1):88–111

Waterfowl Populations in Eastern Lancaster Sound and Western Baffin Bay

The seasonal distributions of oldsquaws (Clangula hyemalis), common eiders (Somateria mollissima) and king eiders (S. spectabilis) were determined through aerial surveys in eastern Lancaster Sound (1976, 1978 and 1979) and northwest Baffin Bay (1978, 1979). Sightings of geese are summarized in an Appendix. The major spring influx of both eiders occurs about the second week of May but most oldsquaws do not arrive until the first half of June. In spring, all three species are rare in offshore areas, are most abundant along coasts in the northern half of the study area, and tend to depart to nesting areas during the last week of June. Oldsqaws molt along coasts of Lancaster Sound and northwest Baffin Bay, but both species of eiders undertake molt migrations. Three waves of eider out-migration were detected in 1976 and 1978. Distribution and movements within the study area are related to probable migrations routes and ice conditions.Key words: oldsquaw, king eider, common eider, geese, aerial surveys, distribution, molt migration, eastern Arctic, Baffin Bay, Lancaster Sound

Vertical Distribution of Zooplankton in Eastern Lancaster Sound and Western Baffin Bay, July-October 1978

Zooplankton samples (n=150) collected from 23 July to 10 October 1978 at 19 oceanographic stations were analyzed for species composition, abundance, biomass and vertical distribution. Sampling was by closing nets hauled vertically at five depth intervals between 0 and 1900 m. At least 116 species were present in the macro-zooplankton of the study area. Species not previously reported from the area included the copepods Spinocalanus horridus, Chiridiella reducta, Derjuginia tolli, Neoscolecithrix farrani?, Pachyptilus pacificus, Haloptilus longicirrus?, Mormonilla polaris, and Monstrilla longicirrus?. In addition, small numbers of the previously undescribed adult male stages of the copepods Aetideopsis multiserrata and A. rostrata were found. Three copepod species that appear to be new to science were also collected. The high numbers of species, new records for the area, and previously undescribed species or stages collected reflect the relatively intensive sampling, particularly in deep water. In general, the zooplankton was numerically dominated by copepods, particularly the calanoids Calanus glacialis, C. hyperboreus, Pseudocalanus minutus, Metridia longa and Microcalanus spp. and the cyclopoid Oithona similis. Most of these species (exceptions: Metridia langa and Microcalanus spp.) were most abundant in the upper 50 m: total zooplankton numbers were also greatest there. However, one or more stages of each of these copepod species, except P. minutus, were present in depths as great as 1900 m. Factor analysis identified 10 zooplankton assemblages. Of these, two were virtually restricted to the upper 50 m, two were mainly in the upper 50 m but were also found throughout the water column, five were primarily deep water groups (one almost entirely restricted to deep water), and one was primarily an intermediate depth group.Key words: zooplankton, vertical distribution, Baffin Bay, Lancaster Sound, species composition, abundance, biomass

Vertical distribution of zooplankton in eastern Lancaster sound and western Baffin Bay, July–October 1978 : Buchanan, R.A. and A.D. Sekerak, 1982. Arctic, 35(1):41–55

Vertical distribution of zooplankton in eastern Lancaster sound and western Baffin Bay, July–October 1978 : Buchanan, R.A. and A.D. Sekerak, 1982. Arctic, 35(1):41–55

Tidal Currents and Inertial Oscillations in Northwestern Baffin Bay

From moored current meter data obtained in 1978 and 1979 in western Baffin Bay and Lancaster Sound, a preliminary analysis was made of the tidal currents and interial oscillations in the area. The tidal currents are relatively small through much of the study area. Offshore, the largest of both the diurnal and the semi-diurnal tidal currents were in all cases less than 8 cm/s in amplitude. In nearshore locations, the tidal currents can be considerably stronger due to internal tides; for example, off Cape Hay on Bylot Island, the K1 tidal currents near the surface were determined to have an amplitude of 15 cm/s. Evidence of inertial oscillations was present in the records from the uppermost current meters on all moorings located at a nominal depth of 35 m. Typical amplitudes were 10 to 20 cm/s, with speeds as high as 35 cm/s being observed. The magnitude of inertial oscillations decreases rapidly with depth; at 250 m, they are greatly reduced in amplitude and are difficult to resolve from the semi-diurnal tidal currents. The inertial oscillations resulted, in large part, from changes in the local surface wind; at times of solid ice cover, their amplitudes were markedly reduced.Key words: Baffin Bay, tidal currents, inertial oscillations, circulation

Major features of the summer near-surface circulation of western Baffin Bay, 1978 and 1979 : Fissel, D.B., D.D. Lemon and J.R. Birch, 1982. Arctic, 35(1): 180–200

Major features of the summer near-surface circulation of western Baffin Bay, 1978 and 1979 : Fissel, D.B., D.D. Lemon and J.R. Birch, 1982. Arctic, 35(1): 180–200