Abstract:

The timing and location of the 2010 Deepwater Horizon (DWH) incident within the Gulf of Mexico pelagic zone likely resulted in exposure of commercially and ecologically important fish species, such as mahi-mahi (Coryphaena hippurus) during the sensitive early life stages. A 24-channel optical fluorescence oxygen sensing system for high through-put respiration measurements was used to investigate the individual and combined effects of oil exposure, temperature and UV-exposure on oxygen consumption rates in embryonic mahi-mahi. Images included in the dataset were used to calculate yolk sac depletion by calculating the number of pixels in both the yolk sac and chorion area of embryos. Raw data on embryo buoyancy (measured on a range of -1 to +1) and hatch rate data are also provided.

Suggested Citation:

Sweet, Lauren; Pasparakis, Christina; Roberts, Aaron P.. 2017. Combined effects of oil exposure, temperature and UV-radiation on buoyancy and oxygen consumption of embryonic mahi-mahi, Coryphaena hippurus. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7GH9G95

Publications:

Pasparakis, C., Sweet, L. E., Stieglitz, J. D., Benetti, D., Casente, C. T., Roberts, A. P., & Grosell, M. (2017). Combined effects of oil exposure, temperature and ultraviolet radiation on buoyancy and oxygen consumption of embryonic mahi-mahi, Coryphaena hippurus. Aquatic Toxicology, 191, 113–121. doi:10.1016/j.aquatox.2017.07.021

Purpose:

Testing combined effects of oil exposure, different rearing temperatures and UV radiation on oxygen consumption, drop rate, buoyancy, hatch rate and energy utilization in embryonic mahi-mahi.

Data Parameters and Units:

Oxygen Consumption (% air saturation and umol L-1)-data found in ‘Microplate Raw Data’ folder within additional folders labeled by the different treatment conditions (temperature oC and salinity trials), microplate number (plate 368 or 538) and trial conducted (Trials 1-4). Data is presented as either % air saturation or umol L-1 by elapsed time (seconds). Date (DD.MM.YYYY HH:MM:SS), Time (seconds). Drop rate (cm/sec)-data found in “Drop Rate” folder for trials conducted at both temperature treatments. Images taken to measure yolk sac depletion- data found in “Yolk Sac Depletion” folder within additional folder labeled by temperature treatment and exposure treatment. Buoyancy (scale of -1 (complete negative buoyancy) to +1 (complete positive buoyancy) and hatch rate (%)- data found in “Buoyancy and Hatch Rate” folder within additional folders labeled by different temperature trials. Sum PAH data- found in folder titled ‘Sum PAH data’. Raw data provided along with break down and percentages of different ringed PAHs. The second tab of the excel files has compiled data and geometric means of initial and final Sum PAH samples.

Methods:

Surface slick oil from the DWH spill was prepared as a high-energy-water-accommodated fraction (HEWAF) to generate environmentally relevant PAH concentrations and compositional profiles. Each HEWAF was prepared on the day of use at a loading rate of 1g of oil per liter of 1 μm filtered, UV-sterilized seawater and mixed in a Waring CB15 blender (Torrington, CT) at low speed for 30 s. The mixture was immediately transferred to a glass separatory funnel and left to settle for 1 hr. The lower 90% of the mixture was then carefully drained and retained for subsequent use as 100% WAF (unfiltered) that was diluted to 4% using UV-sterilized seawater for test exposures. 4% HEWAF dilutions were used for treatment exposures (Oil only and UV + Oil). UV-sterilized seawater was used for control treatments (Control and UV Only). Loligo microplate was used to measure oxygen consumption in developing mahi-mahi. Yolk sac and embryo area were measured using ImageJ version 1.46r (rsbweb.nih.gov/ij/) from a perimeter drawn with the freehand tool enclosing the area.

Instruments:

Oxygen Consumption- Loligo Microplate (24 well optical-fluorescence, oxygen-sensing system). Images and videos were taken using either a Fire-i400 or Fire-i530c digital camera (Unibrain, San Ramon, CA) mounted on a Nikon SMZ800 stereomicroscope. UVA light bulbs were purchased from HTG Supply (Callery, PA, USA). Irradiance (λ= 380 nm) was measured continuously throughout the UV co-exposures using BioSpherical radiometers (BioSpherical Instruments, Inc., San Diego, CA, USA).

Individual Files: