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Five marine mammal surveys between 2008 and 2011 were conducted aboard the Buque de Investigacion Orion (the research vessel for the Oceanographic Institute of the Ecuadorian Navy) within oceanic waters adjacent to mainland Ecuador and the Galapagos Islands. The surveys dedicated extensive time in deep, offshore waters where cetaceans were not densely present. Sightings of 12 species were compared with an earlier survey aboard the B/I Orion in 2001 as well as with a subset of published data from three NOAA STAR ( Stenella Abundance Research) surveys between 1999 and 2003. Additionally, a small boat, near-shore survey, was conducted during June 2010 among and near the Galapagos Islands. Encounter rates ranged annually from 0.012 cetacean/km to 0.027 cetacean/km. The highest encounter rate aboard the B/I Orion took place during the April 2009 survey. In order to compare sighting rates between the B/I Orion and NOAA platforms, the average effective half-strip widths were used to determine encounter rates per area effectively searched. A zonation within the study region was observed between odontocete and balaenopterid cetaceans as well as between striped ( Stenella coeruleoalba ) and short-beaked common dolphins ( Delphinus delphis ). Several methodological aspects of surveys and geographical features that may influence encounter rates and subsequent abundance estimates are discussed. This study demonstrates that vessels of opportunity provide a valuable means of studying open-ocean and coastal distributions of marine mammals. Possible methodological improvements, such as the use of high-power binoculars, that could increase the absolute number of sightings, the efficiency of these opportunistic surveys, and improve the sighting rates of more evasive species are discussed.

Eddies along the eastern shelf-break of the Bering Sea play an important role in the physics, chemistry, and biology of the region. Eddy activity in this region is particularly strong near the major shelf-break canyons during the spring months, likely influencing the spring bloom. Spring eddy activity is negatively correlated with the North Pacific Index, a measure of the strength of the Aleutian Low. A strong Aleutian Low (negative NPI) is related to a strong sub-polar gyre, suggesting that spin-up of the gyre results in more eddy activity in this region. In situ data from an eddy sampled near Pribilof Canyon in 1997 suggest that these eddies can carry water from the outer shelf into the basin. Drifters rotating around the eddy at different radii exhibited differing rotation periods suggesting that the eddy was not rotating in solid body rotation. Thus horizontal exchange of water within the eddy may result in the excess nutrients and fresher water within the core of the eddy exchanging with the basin over time, influencing chlorophyll-a distributions throughout the summer months.

[1] Brominated very short-lived substances (VSLSs) such as bromoform (CHBr3), dibromomethane (CH2Br2), and chlorodibromomethane (CHClBr2) are receiving increasing attention, due to their important role in tropospheric and lower stratospheric ozone (O3) chemistry. These brominated VSLSs were measured in air and surface water during the Gulf of Mexico and East Coast Carbon (GOMECC) cruise in the summer of 2007. Mean atmospheric mixing ratios for CHBr3, CH2Br2 and CHClBr2 for the entire cruise were 14.6 (0.7 to 138.3) ppt, 2.8 (0.5 to 13.2) ppt, and 0.5 (0.03 to 3.2) ppt, respectively; and mean sea-surface water concentrations were 66.0 (4.4 to 1724.8) pmol L−1, 10.6 (1.9 to 153.8) pmol L−1, and 1.0 (0.1 to 17.2) pmol L−1, respectively. These compounds were supersaturated almost everywhere in the study region, except a few locations in the Florida Straits and along the east coast of Florida, where negative saturation anomalies and fluxes were observed. Mean net fluxes observed during the GOMECC cruise for CHBr3, CH2Br2, and CHClBr2 were 47.6 (−25.4 to 1056.3) nmol m−2 d−1, 9.7 (−0.5 to 112.3) nmol m−2 d−1, and 0.8 (−1.2 to 10.8) nmol m−2 d−1, respectively. The net fluxes for these polybrominated compounds from the coastally influenced waters (bottom depth ≤200 m) are significantly higher than the net fluxes observed in the open ocean (bottom depth >200 m).

[1] Measurements of methyl bromide (CH3Br) and methyl chloride (CH3Cl) were made during the Gulf of Mexico and the East Coast Carbon (GOMECC) cruise in the summer of 2007. This was the first large-scale study of CH3Br and CH3Cl in the coastal ocean. The mean atmospheric mixing ratios were 10.1 ppt for CH3Br and 517 ppt for CH3Cl. Surface seawater concentrations ranged from 0.8 pM to 5.0 pM for CH3Br and from 61.5 pM to 179 pM for CH3Cl. Biological processes contribute to the elevated seawater concentrations of CH3Br, while a combination of biological processes and terrestrial sources may contribute to elevated seawater concentrations of CH3Cl. Vertical distributions show highest concentrations of CH3Br and CH3Cl in the subsurface seawater below the mixed layer due to high degradation rates near the surface. Good correlation of the production rates between CH3Br and CH3Cl suggests they have some common sources in the coastal ocean. After excluding the open ocean points, annual coastal emissions in the studied region were 0.01–0.06 Gg yr−1 for CH3Br and 0.3–1.6 Gg yr−1 for CH3Cl. By simple extrapolation, the global coastal emissions were estimated at 0.5–3.6 Gg yr−1 for CH3Br and 19–98 Gg yr−1 for CH3Cl. Including the coastal ocean emissions of CH3Br and CH3Cl will increase the estimate of global oceanic emissions by 1%–9% and 1%–8%, respectively.

Marine mammals in the Eastern Equatorial Pacific play a vital ecological role toward structuring trophic systems and the distribution commercially valuable prey. However, scientific study of their populations within the waters surrounding Ecuador has been only infrequently conducted and largely neglected over the past decade. Our research including six marine mammal surveys will investigate the distribution of marine mammals inhabiting the oceanic areas between the Ecuadorian mainland and around the Galapagos Islands. Visual observers documented marine mammal sightings while aboard the Ecuadorian Navy's Oceanographic Vessel the (B/I) Orion last September/October 2008 and April 2009. The range of different species positively identified as well as the large proportion of sightings that could not be identified to species using current survey methodologies, suggests that the diversity and overall marine mammal abundance within Ecuadorian waters may be much higher than previously suspected. Four more surveys covering similar periods of the year will be conducted over the next two years. Biological patterns in this region are closely tied to physical features. Using satellite data, Palacios (2004) discerned seasonal patterns in the surface concentrations of chlorophyll off the West coast of the Galapagos Islands. Here, upwelling driven productivity (which is initiated by the subsurface derived macronutrients) is enhanced by iron inputs derived from the island platform. The confluence of the Equatorial Undercurrent and Peru Current create an area around the islands where enhanced levels of nutrients are available to the ocean's biology. Palacios' harmonic analysis of ocean color data showed that the seasonal cycle of warming and cooling is associated with the North-South migration of the ITCZ and that ocean color which is related to surface primary productivity follows these seasonal SST patterns. Daniel Palacios identified groups of cetacean species that were often sighted in close proximity and described 3 main habitat types around the islands where these groups were found: upwelling modified, stratified, and near-shore. He defined these habitats using composited data from multiple sensors over 9.28 km spatial resolution and averaged over several years to obtain seasonal climatological pictures of cetacean habitat. I will use ocean color from the NASA's Earth observing sensor MODIS (Moderate Resolution Imaging Spectroradiometer) sensor at the same spatial resolution but averaged over days to weeks of time in order to look at more temporally variable processes. Additionally, it may be possible to identify frontal boundaries based on changes in surface chlorophyll-a concentrations. I will compare the spatial and temporal difference between marine mammal sightings and these frontal boundaries. Oceanographic cruises aboard the Orion provide an excellent platform for regular marine mammal surveys to assess the current range of species present in Ecuadorian waters as well as establish a system of surveys that will improve marine resource management in this sensitive ecosystem. These surveys combined with remote sensing data from MODIS, will also provide useful insight into how the distribution of marine mammals is structured in relation to physical environmental features and the underlying biology. Ultimately, we hope to improve the tools and conservation methodologies available to marine resource managers.