Final Report
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FOR OSRI USE ONLY Oil Spill Recovery Institute OSRI PROPOSAL Grant Application NUMBER DATE RECEIVED PROJECT TITLE Sensitivity of Arctic cod embryos and larvae to oil; delayed impacts on juvenile growth and lipid condition. EMPLOYER INDENTIFICATION NUMBER RFP TITLE (EIN) or (TIN) N/A See attached cover sheets by institution DATE SUBMITTED # OF COPIES IS THIS AWARD 09/26/2017 1 [X] NEW RENEWAL NAME AND ADDRESS OF ORGANIZATION NAME AND ADDRESS OF PERFORMING TO WHICH AWARD SHOULD BE MADE ORGANIZATION IF DIFFERENT See attached cover sheets by institution Same IS AWARDEE ORGANIZATION (Check All That Apply) UNIVERSITY AGENCY NON-PROFIT FOR-PROFIT INDIVIDUAL SMALL BUSINESS MINORITY BUSINESS WOMEN-OWNED BUSINESS CHECK APPROPRIATE BOX(ES) for area to which the proposal applies FELLOWSHIP SMALL AWARD < $25,000 MEDIUM AWARD $25,000 to <$100,000. LARGE AWARD $100,000 or greater. REQUESTED AMOUNT PROPOSED DURATION (1- REQUESTED $53,194 (OSU) 60 MONTHS) STARTING DATE $24,072 (NOAA) 12 November 1, 2017 NAMES Telephone Electronic Mail Address PRINCIPAL INVESTIGATOR Benjamin J. Laurel 541-867-0197 [email protected] CO-PRINCIPAL INVESTIGATOR Louise A. Copeman & John Incardona BUSINESS OFFICER To the best of my knowledge and belief, all data in this application/pre-application are true and correct, the document has been duly authorized by the governing body of the applicant and the applicant will comply with the attached assurances if the grant is awarded. Typed Name of Authorized Representative Title Telephone No. See attached cover sheets by institution See attached cover sheets by institution Signature of Authorized Representative Date Signed 9/25/17 *SUBMISSION OF SOCIAL SECURITY NUMBERS IS VOLUNTARY AND WILL NOT AFFECT THE ORGANIZATION’S ELIGIBILITY FOR AN AWARD. OSRI Form 10/16 PROJECT SUMMARY Arctic cod (Boreogadus saida) are important components of Arctic food webs, channeling lipid- rich energy between plankton and higher trophic levels such as marine mammals and seabirds. Arctic cod have physiology adapted for growing and storing energy in their cold-water environment, but environmental conditions that reduce growth or energy allocation (e.g., temperature, disease, toxins) will likely reduce their overwintering survival in their 1st year of life. The objective of this project is to quantify the delayed impacts of embryonic oil exposure on growth and energetic condition (lipid content) of later larval and early juvenile stages of Arctic cod. By addressing the non-lethal chronic effects of embryonic oil exposure to later life stages in Arctic cod this project will provide an ecologically meaningful measure of injury assessment for this species. Further, this project will deliver information on how low dose oil-exposure (100 μg oil/L) affects Arctic cod quality as a forage fish for higher trophic levels. This research directly addresses OSRI’s mission by providing measurable damage assessment characteristics in Arctic cod (lipid content, growth rate). This will help scientists, industry and Arctic communities understand the delayed long-range effects of low-dose embryonic exposure to a key-stone fish species and indirectly to the health of the Arctic marine ecosystem. Measurements and techniques developed in this project could be widely adapted to other important gadids in the sub-Arctic region such as walleye pollock (Gadus chalcogrammus) or Pacific cod (Gadus macrocephalus), the two most commercially important ground fisheries in the USA. This proposed research capitalizes and directly builds on recent live-animal experiments on Arctic cod within NOAA-AFSC (~$900,000) and $200,000 of new 2016-17 investment by NOAA ORR towards embryonic oil exposure experiments on Arctic cod. PROJECT DESCRIPTION Background: Arctic cod (Boreogadus saida) is a federally managed species in the Chukchi and Beaufort Seas with an abundant, wide-spread distribution throughout the circumpolar Arctic region (NPFMC 2009). Arctic cod have a pelagic life-history and episodically occupy coastal zones (Craig et al. 1982) and serve an essential component of polar food webs by transferring energy from the plankton to upper trophic levels such as marine mammals, birds, and other fish (Fig. 1, Whitehouse et al. (2014). Significant changes in the abundance and distribution of Arctic cod will likely be catastrophic, leading to widespread food web changes, particularly in ice- obligate species. As a key-stone species, the loss of Arctic cod will likely lead to a reorganization of the Figure 1. The mid-trophic level fish trophic community structure in the Arctic (Bluhm & assemblage of Arctic cod forms a Gradinger 2008). critical link in the food web (from Moore & Stabeno 2015). The population dynamics of Arctic cod are poorly understood, but the overwintering period is considered a critical period for most marine fish species in Arctic regions. Juvenile fish must develop, grow and store lipid reserves rapidly during their first year to minimize predation and maximize overwintering survival (Sogard 1997, Copeman et al. 2008). This is especially important in the Arctic where the summers are short and prolonged winter-spring temperatures are <0 °C (Bouchard & Fortier 2008, 2011). High levels of lipid storage at the end of the short and pulsed summer feeding period are essential for Arctic fish species to survive harsh overwintering conditions of sub-zero temperatures and scarce food resource lasting up to nine months. Therefore, environmental conditions that reduce growth or energy storage in the form of lipids may reduce recruitment to the adult population by way of size- and energy-dependent overwintering survival. Despite this knowledge very few toxicology experiments have followed the long-term growth of fish and potential recruitment dynamic impacts caused by embryological exposure to oil (Heintz et al. 2000). Increased interest in offshore oil development and the presence of higher amounts of ship traffic in the Arctic threaten poorly understood ecologically important marine species. Determining possible injuries to Arctic cod from oil exposure is critical to predicting and determining the impacts of an oil spill on this keystone species and the Arctic ecosystem, which aligns with OSRI’s mission to understand the effects of spilled oil on Arctic environments. In 2017, funding from NOAA-ORR and in kind support from NOAA-NMFS (AFSC and NWFSC), supported the first embryonic exposure experiment of Arctic cod to low concentrations of crude oil (controls, 100, 300, 900 ug/L whole oil exposure equivalent to 1 – 9 ug/L total PAH). Embryos were exposed to environmentally relevant concentrations of oil for a short 3 day period (~5% of their egg stage duration) using a new continuous generated oil dispersion laboratory (Fig 2., SINTEF methods; Nordtug et al. (2011)). A C B Figure 2. The experimental set-up for embryonic exposure of Arctic cod to Alaskan crude oil showing: (A) the large flow-through cold water tanks housing exposure units and tubing from the SINTEF dosing system, (B) a close-up of the surface in glass exposure tanks demonstrating the dose- dependent slick formation and (c) a schematic of the exposure unit showing embryos exposed to a surface slick for 3 days followed by a 4 day wash-out period. Results from this short embryonic exposure indicated a clear dose-response effect in larval phenotypes, particularly in cardiac and craniofacial defects that have been described in other fish species (Fig. 3a, Incardona et al. (2005)). Exposed embryos also had reduced size-at-hatch (Fig. 3b) and reduced initial growth during the first 2 weeks after yolk absorption. Fig 3. The morphology at hatch shows a clear dose response demonstrate with increased level of edema around the yolk and high rates of facial deformities in the 900 and 300 μg oil/L water treatment. Further, a significant effect of oil dosage on standard length at hatch was measured and explained 94% of the variance in size-at-hatch. Characterizing the energetic status of fish can be done in numerous ways (e.g., Fulton’s K, hepatosomatic index) but is most accurately achieved by measuring the amount of lipids in different body tissues. Lipids are a limiting nutrient in cold-water marine food webs (Litzow et al. 2006) and are particularly restrictive to growth and survival at the onset of first-feeding (Sargent et al. 1999) and during the juvenile stages of marine gadid development (Copeman et al. 2008, Copeman et al. 2009). The major lipid classes in fish include triacylglycerols (TAG), sterols (ST) and phospholipids (PL) (Parrish 1998). TAG is the major storage lipid class in gadids while PL and ST are important components of cellular membranes. However, recently PL has also been demonstrated to be an important energy source for eggs, larvae as well as low-lipid juveniles ((Copeman et al. 2008, Laurel et al. 2010). Improvements in fish condition in Atlantic herring (Clupea harengus), Atlantic cod (Gadus morhua) and Pacific cod have previously been attributed to elevated total lipid, TAG density and TAG/ST ratios (Lochmann et al. 1995, Copeman & Laurel 2010). As such, these detailed lipid metrics provide an accurate reflection of overall fish condition, and given their near instantaneous tissue incorporation (Amara et al. 2007, Copeman & Laurel 2010), are well-suited for assessing the impacts of environmental conditions on fish performance and health. Fig 4. Total storage lipids (μg/individual, yolk lipids) in Arctic cod larvae at fertilization (day-0), post-exposure (day 26) and at hatch (day 44) in larvae exposed to the 900, 300, 100 μg oil/L water treatment plus a control. Data represent the mean ± SE of four replicate tanks. Significant differences at P<0.05, ANOVA with Tukey’s Pairwise comparison. Lipid analyses has been completed on Arctic cod eggs at fertilization, eggs from each treatment post exposure and on larvae at 100% hatch. Total lipids and lipid classes were not significantly different between oil treatments in eggs post-exposure. However, at hatch larvae showed significant differences in their lipid class composition.