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Assessment of zooplankton abundance, distribution, community composition, and temporal variability is critical to understanding the effects of climate variability and change on lower trophic level production and availability for consumption by larger consumers. Zooplankton sampling is performed across the Canadian continental shelf system by Fisheries and Oceans Canada's Atlantic Zone Monitoring Programme (AZMP). Sampling includes semi-monthly to monthly collection of zooplankton using vertical net tows (VNTs) deployed from near-bottom to surface at stations on the central Scotian Shelf (Stn 2, 150 m depth) and Newfoundland Shelf (Stn 27, 175 m depth), and by Continuous Plankton Recorders (CPRs) in the near-surface layers along routes over the Scotian and Newfoundland shelves (0–10 m depth). Here, we compare abundance metrics for 11 copepod taxa collected using both gear types in both regions between 1999 and 2015. Seasonal cycles of VNT and CPR abundance were similar for near-surface residents. VNT: CPR abundance ratios varied year-round for vertical migrants, as ontogenetic migrants shifted their vertical distribution, and as diel migrants changed their migratory behaviour. For some taxa, differences in annual average VNT: CPR abundance ratios between regions suggest differences in vertical distribution, while for others differences in inter-annual variability for VNT and CPR abundances suggest differences in the dynamics of the near- and sub-surface components of the populations.

The North Atlantic right whale (NARW), Eubalaena glacialis, resides primarily on western North Atlantic continental shelves where this endangered species is susceptible to vessel strike and entanglement in fishing gear. Mitigation of these threats is dependent on the ability to predict variations in NARW occurrence. North of the Mid-Atlantic Bight, the distribution of NARWs is influenced by their prey, mainly copepods of the genus Calanus. We review factors that promote suitable foraging habitat from areas where NARWs have been observed feeding. We then synthesize our findings within a conceptual framework in which availability (i.e. shallow prey depth), supply, and aggregation of prey occur together to facilitate suitable foraging habitat. By definition, the depth of prey on the shelf is constrained to ≤200 m and other mechanisms may occur locally that further enhance prey availability. Enhanced production of prey occurs in coastal currents, which transport the copepods to NARW foraging areas. Prey concentrating mechanisms are not well-characterized. Information gaps that impede rapid and dynamic prediction of suitable foraging habitat include limited data on the spatial and temporal variation of prey and environmental conditions at local scales (i.e. 0.1–1 km), motility of prey, and diving behaviour of NARWs.

The spatial distribution of zooplankton is influenced by complex interactions among population dynamics, vertical positioning and advection. We used empirical observations and particle tracking simulations to investigate variation in horizontal distribution of Calanus spp. and three neritic copepod taxa (Acartia spp., Pseudocalanus sp. and Temora longicornis) in the southern Gulf of St. Lawrence (sGSL) in October 2018. These copepods are potential prey for fish and the endangered North Atlantic right whale, Eubalaena glacialis. We quantified horizontal variation in abundance from a plankton survey, and obtained vertical distributions from a subset of locations and a process study conducted over ~1 day. Horizontal distributions of Calanus finmarchicus and Pseudocalanus sp. were widespread, whereas those of Calanus hyperboreus and C. glacialis were centred in the interior of the sGSL and those of Acartia spp. and T. longicornis were centred on the western side. Horizontal distributions of C. hyperboreus–C. glacialis and C. finmarchicus–Pseudocalanus sp. pairs were highly correlated. Contrasting distributions among C. finmarchicus and its congeners reflect interspecific differences in life history strategy and its interaction with ocean circulation. In autumn, a shift to increased current strength and flow-through circulation may lead to enhanced losses of Calanus spp. in the absence of upstream replenishment.

Linking production, transfer and subsequent bioavailability of nutritionally significant matter from phytoplankton to higher trophic levels is a fundamental aspect in understanding marine food webs. The plant–animal interface is of interest because of the highly variable transfer between producers and consumers, and the myriad of factors that influence it. Essential fatty acids (EFAs) are dietary nutrients that are necessary for normal function in all consumers, yet it remains unclear how efficiently they are transferred through marine food webs. We introduced a 13C-labelled carbon source to the cryptophyte Rhodomonas salina to quantify primary production of two omega-3 long-chain polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We investigated transfer and assimilation efficiencies of these EFAs from phytoplankton to the calanoid copepod Calanus finmarchicus in an 8-day feeding experiment. We found low production of both EFAs in R. salina. Assimilation efficiencies of both EFAs ranged from 5 to 15% throughout the experiment, remaining slightly higher on average for DHA. This was mirrored in more efficient trophic transfer of DHA (up to 28%, compared to 13% for EPA). These results add to previously scarce experiments empirically quantifying the assimilation and transfer efficiency of EFAs in a basic marine planktonic food chain.

This study aimed at identifying potentially suitable foraging habitats for the North Atlantic right whale (NARW; Eubalaena glacialis) in the Gulf of St Lawrence (GSL), on the Scotian Shelf (SS) and in the Bay of Fundy (BoF), Canada, based on the distribution densities of their main prey, Calanus copepod species. More than 4800 historical Calanus spp. water column integrated samples as well as 221 vertically stratified sampling stations were used to create a 3D (latitude, longitude and vertical) climatology of Calanus spp. biomass densities for spring and summer–fall when NARW are feeding in Canadian waters. We then combined this 3D preyscape with bio-energetic considerations to highlight potentially suitable NARW foraging habitats in the region. Our 3D climatological approach successfully identified the known feeding areas of Grand Manan (BoF) and Roseway Basin (western SS), confirming its validity. Expanding our analyses to the GSL and other parts of the SS, we identified in both regions areas previously unknown where Calanus spp. biomass densities exceeded minimum levels suitable for foraging NARW. Our results represent a key contribution to the identification of important foraging areas for NARW in Canadian waters, especially in the context of climate change and the documented shift in NARW distribution.

Introduction While research suggests that asylum-seekers often present with a high level of medical and psychological needs, there is a dearth of research exploring sleep quality in this population, and, accordingly, the role that the sleep medicine community may be able to play in alleviating the suffering of this population. Therefore, this study aims to assess the prevalence of sleep disruption amongst asylum-seekers presenting to a South Florida clinic and to categorize these disruptions according to severity and type. Methods This is a cross-sectional study utilizing medical affidavits for asylum seekers in South Florida from 2018-2020 (n=54). Affidavits were reviewed for narrative descriptions of sleep quality and information from validated screeners regarding sleep; demographic information was also collected. Affidavits were excluded if they did not include itemized answers to screening questions. Results Out of 54 asylum-seekers (31% male, median age=34.5 years), 72.2% reported sleep disturbance. 38.9% reported nightmares, 66.7% reported insomnia of any type, and 29.6% reported severe insomnia. Asylum-seekers that screened positive for post-traumatic stress disorder (PTSD) were more likely to report ongoing sleep disturbance than asylum-seekers that screened negative for PTSD (p=.004). Sleep disturbance prevalence did not vary significantly by gender identity or country of origin. Conclusion This study reveals a high prevalence of sleep disruption amongst asylum-seekers in South Florida. The asylum-seekers in our study were more likely to experience insomnia than nightmares, but many experienced both; sleep disturbance was significantly associated with screening positive for PTSD. Our findings suggest that physicians working with asylum-seekers should ask about sleep quality and offer appropriate care. Directions for further research include investigating how poor sleep quality impacts the health and wellbeing of asylum-seekers. Support (if any) None

The Pneumonia Etiology Research for Child Health (PERCH) study is the largest multicountry etiology study of pediatric pneumonia undertaken in the past 3 decades. The study enrolled 4232 hospitalized cases and 5325 controls over 2 years across 9 research sites in 7 countries in Africa and Asia. The volume and complexity of data collection in PERCH presented considerable logistical and technical challenges. The project chose an internet-based data entry system to allow real-time access to the data, enabling the project to monitor and clean incoming data and perform preliminary analyses throughout the study. To ensure high-quality data, the project developed comprehensive quality indicator, data query, and monitoring reports. Among the approximately 9000 cases and controls, analyzable laboratory results were available for ≥96% of core specimens collected. Selected approaches to data management in PERCH may be extended to the planning and organization of international studies of similar scope and complexity.

Between 2014 and 2016, an interdisciplinary team of researchers including physical oceanographers, biologists, economists and anthropologists developed a working example of an Integrated Ecosystem Assessment (IEA) for three ecologically distinct regions of the Northwest Atlantic; Georges Bank, the Gulf of Maine and the Grand Banks, as part of the International Council for the Exploration of the Sea (ICES) Working Group on the Northwest Atlantic Regional Sea (WGNARS). In this paper, we review the transdisciplinary and collaborative process by which the IEA was developed, with a particular focus on the decision points arising from the IEA construct itself. The aim is to identify key issues faced in developing any IEA, practical decisions made to address these issues within the working group and lessons learned from the process.

Keister, J. E., Bonnet, D., Chiba, S., Johnson, C. L., Mackas, D. L., and Escribano, R. 2012. Zooplankton population connections, community dynamics, and climate variability. – ICES Journal of Marine Science, 69: 347–350.

Johnson, C. L., Leising, A. W., Runge, J. A., Head, E. J. H., Pepin, P., Plourde, S., and Durbin, E. G. 2008. Characteristics of Calanus finmarchicus dormancy patterns in the Northwest Atlantic. – ICES Journal of Marine Science, 65: 339–350. Demographic time-series from four fixed stations in the Northwest Atlantic Ocean demonstrate variable timing of entry into and emergence from dormancy in subpopulations of the planktonic copepod Calanus finmarchicus. A proxy for timing of entry was established as the date each year when the proportion of the fifth copepodid stage (CV) in the subpopulation rose to half its overall climatological maximum CV proportion at that station. The proxy for timing of emergence at each station was set as the first date when adults were more than 10% of the total abundance of copepodid stages. An alternate emergence proxy date was determined by back-calculating the spawning dates of the first early copepodid stages appearing in spring, using a stage-structured, individual-based model. No single environmental cue (photoperiod, surface temperature, or average surface-layer chlorophyll a concentration) consistently explained entry or emergence dates across all stations. Among hypotheses put forward to explain dormancy in Calanus species, we cannot eliminate the lipid accumulation window hypothesis for onset of dormancy or a lipid-modulated endogenous timer controlling dormancy duration. The fundamental premise of these hypotheses is that individuals can only enter dormancy if their food and temperature history allows them to accumulate sufficient lipid to endure overwintering, moult, and undergo early stages of gonad maturation.