Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Related Publications
• Parameters
• Instruments
• Project Information
• Funding

Survival source data of 2016-2018 experimental work on the sensitivity of northern sand lance offspring to combined ocean warming and acidification.

Spawning-ripe sand lance were collected from SBNMS (42° 9' 58.26'' N, 70° 18' 44.19'' W) on 2 December 2016 and 22 November 2017, using a 1.3 × 0.7 m beam trawl (6 mm mesh) towed at 3 knots for 15 minutes.

We tested factorial combinations of three pCO2 × three temperature levels. The target for pCO2 controls was 400 µatm (~8.15 pHNIST), a level characteristic of the average open ocean and of the A. dubius spawning habitat in late fall (Salisbury and Jönsson, 2018). As contrasts, we chose 1,000 µatm (~7.78 pH) and 2,100 µatm (~7.48 pH), which correspond to predicted average ocean pCO2 levels by the years 2100 and 2300, respectively.

Response traits: Treatment-specific embryo survival was calculated in trials 1 and 3 as the proportion of hatchlings relative to the number of fertilized embryos (%), while in trial 2 the total number of hatchlings was used as a proxy for embryo survival. In trial 3, fertilization success (%) was calculated as the sum of hatched larvae + arrested embryos divided by 300. Treatment-specific daily hatch frequencies (= daily treatment hatch/total hatch within temperature treatment) were calculated for trials 2 and 3.

Data processing: Data were cross-checked with hand-written notes, checked for outliers/erroneous entries/numbers.

BCO-DMO Data Processing:
- modified parameter names (replaced spaces with underscores, replaced "%" with "pcnt")
- converted latitude and longitude from degrees, minutes, seconds to decimal degrees
- reformatted date from mm/dd/yyyy to yyyy-mm-dd
- replaced "n/a" with "nd" (no data);
- replaced earlier copy of data (2018-11-07) with revised copy on 2019-09-20;
- version 2 published on 2021-05-27. This version contains corrections to the pcnt_hatching_success data values.

Objectives:
This proposal will quantify the sensitivity of a key forage fish in the Northwest Atlantic to the individual and combined effects of the major factors comprising the ocean climate change syndrome: warming, acidification, and deoxygenation. We will rear embryos of Northern sand lance Ammodytes dubius, obtained by strip-spawning wild adults from the Stellwagen Bank National Marine Sanctuary (SBNMS) through larval and early juvenile stages in a purposebuilt factorial system at different factorial combinations of temperature × CO2 × oxygen.

Our first objective is to quantify individual and combined effects of temperature × CO2 (year 1) and temperature × CO2 × DO (year 2) on A. dubius growth and survival. We hypothesize that warming in combination with high CO2 (low pH) will have additive or synergistically negative effects, whereas the addition of low DO as a third stressor will have stark, synergistically negative effects on all traits.

Our second objective is to characterize the swimming behavior of A. dubius larvae that have been reared under combinations of elevated temperature × CO2. We hypothesize that combined stressors will have synergistically negative effects on the development of larval sensory systems, which express themselves and can thus be quantified as changes in larval swimming behavior.

Our third objective is to take advantage of the rare winter sampling activities for this project to quantify CO2, pH, and DO variability in benthic waters on Stellwagen Bank through bottle collections and short-term sensor deployments. We hypothesize that bottom water pH and DO levels during the sand lance spawning season might be routinely lower than levels in surface waters.