Abstract:

Oysters in the Gulf of Mexico were likely subjected to multiple stressors as a result of the Deepwater Horizon Oil Spill – those directly from the spill and those indirectly from the spill in the form of clean-up/response activities. The effect on oysters may have been influenced by the genetic diversity of oysters in the Gulf of Mexico. The data here are from a laboratory experiment assessing the effects of oil, dispersants, and salinity on oysters of varying genetic diversity. Diversity levels included monocultures of offspring from each of 5 different parental pairs and multiple polycultures of offspring from 2 and 3 different parental pairs. Oil exposures included no oiling (seawater only), oil, and oil with dispersant. Salinity regimes were either low (5–10 ppt) or control (15-20 ppt) salinity. Survival, growth and condition of juvenile oysters were assessed after 21 days of exposure. The mortality dataset reports the number of live and dead oysters counted for each experimental tank at the end of the experiment. The shell height dataset reports shell heights measured for a subset of 20 oysters from each treatment combination. The before and after condition datasets report the shell heights and multiple weights to be used for calculating oyster condition, both before the start of the experiment and again at the conclusion of the experiment. The water quality dataset reports the temperature and salinity in each of the experimental systems over the course of the 21 day experiment. Lastly, the TPH_PAH dataset reports the values of total petroleum hydrocarbons and polycyclic aromatic hydrocarbons in the water of each experimental treatment over time.

Suggested Citation:

Meagan Shrandt, Sean Powers. 2017. Examining the role of intraspecific oyster diversity in response to oiling, dispersant, and salinity – a mesocosm study in September/October 2016. Distributed by: Gulf of Mexico Research Initiative Information and Data Cooperative (GRIIDC), Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7VQ30QZ

Publications:

Schrandt, M., Powers, S., Rikard, F. S., Thongda, W., & Peatman, E. (2018). Short-term low salinity mitigates effects of oil and dispersant on juvenile eastern oysters: A laboratory experiment with implications for oil spill response activities. PLOS ONE, 13(9), e0203485. doi:10.1371/journal.pone.0203485

Purpose:

The purpose of this manipulative mesocosm study was to evaluate how the genetic diversity of juvenile oysters plays a role in the resilience of oysters to the effects of multiple-stressors associated with oil spills and their response activities (i.e. oil, dispersants, fresh water input).

Data Parameters and Units:

ACER_Oyster_Mortality.csv Tank: the specific tank in the experiment (numbered from 1–330) GeneticID: the genetic group assignment of the oysters (options include 1 of 11: A, B, C, D, E, AB, AE, BD, ABC, BCE, CDE). Each letter corresponds to individuals from a single parental pair (i.e. these oysters are full siblings). For example, “A” oysters are offspring from one parental pair; “B” oysters are offspring from a second parental pair. Genetic IDs with a mixture of letters indicate that siblings from multiple parental pairs were mixed. For example, a genetic ID of “AB” indicates half the oysters in the tank are full siblings from parental pair “A” and half the oysters are full siblings from parental pair “B”. For polycultures of three letters, a third of the oysters in the tank are from each respective parental pair. DiversityLevel: the number of genetic IDs represented in the tank (options include 1 (monoculture), 2 or 3 (polycultures)) Mono_Poly: tank assignment as to whether the genetic diversity is a monoculture (all direct siblings) or a polyculture (mix of multiple sibling groups) Salinity: the salinity group assignment (options include either low or meso); low is 5-10 ppt and meso is 15-20 ppt Oil: oiling category group assignment (options include none, oil, oil+dispersant) Dead: the number of dead oysters counted at the end of the 21 day experiment Live: the number of live oysters counted at the end of the 21 day experiment ACER_Oyster_ShellHeight.csv Tank: the specific tank in the experiment (numbered from 1–330) Replicate: the replicate oyster number measured for shell height from the given tank; a total of ten oysters were measured for shell height in a subset of the experimental tanks; NA indicates this tank was not measured for shell height GeneticID: the genetic group assignment of the oysters (options include 1 of 11: A, B, C, D, E, AB, AE, BD, ABC, BCE, CDE); Each letter corresponds to individuals from a single parental pair (i.e. these oysters are full siblings). For example, “A” oysters are offspring from one parental pair; “B” oysters are offspring from a second parental pair. Genetic IDs with a mixture of letters indicate that siblings from multiple parental pairs were mixed. For example, a genetic ID of “AB” indicates half the oysters in the tank are full siblings from parental pair “A” and half the oysters are full siblings from parental pair “B”. For polycultures of three letters, a third of the oysters in the tank are from each respective parental pair; NA indicates this tank was not measured for shell height DiversityLevel: the number of genetic IDs represented in the tank (options include 1 (monoculture), 2 or 3 (polycultures)); NA indicates this tank was not measured for shell height Mono_Poly: tank assignment as to whether the genetic diversity is a monoculture (all direct siblings) or a polyculture (mix of multiple sibling groups); NA indicates this tank was not measured for shell height Salinity: the salinity group assignment (options include either low or meso); low is 5-10 ppt and meso is 15-20 ppt Oil: oiling category group assignment (options include none, oil, oil+dispersant) StartShellHeight: measured shell height before the experiment began; shell height was measured from the umbo to the leading edge of the valve, in millimeters; NA indicates this tank was not measured for shell height EndShellHeight: measured shell height for live oysters at the end of the 21 day experiment; shell height was measured from the umbo to the leading edge of the valve, in millimeters; NA indicates this tank was not measured for shell height ACER_Oyster_BeforeCondition.csv Oyster: ID of the individual oyster. The letter indicates the genetic group; all oysters with the same letter are full siblings (come from the same parental pair) ShellHeight: measured shell height before the experiment began; shell height was measured from the umbo to the leading edge of the valve, in millimeters WholeWetWeight: weight of the intact oyster, in grams MeatWetWeight: wet weight of the oyster tissue, in grams DryShellWeight: dry weight of the oyster shell after drying 48 hours on the counter, in grams DryMeatWeight: dry weight of the oyster tissue after drying 48 hours at 60 degrees Centigrade, in grams ACER_Oyster_AfterCondition.csv Tank: the specific tank in the experiment (numbered from 1–330) Oyster: ID of the individual oyster. The first number corresponds to the shelving system and the letters indicate the genetic group. The last set of numbers is the replicate for that genetic group in the particular shelving system. GeneticID: the genetic group assignment of the oysters (options include 1 of 11: A, B, C, D, E, AB, AE, BD, ABC, BCE, CDE); Each letter corresponds to individuals from a single parental pair (i.e. these oysters are full siblings). For example, “A” oysters are offspring from one parental pair; “B” oysters are offspring from a second parental pair. Genetic IDs with a mixture of letters indicate that siblings from multiple parental pairs were mixed. For example, a genetic ID of “AB” indicates half the oysters in the tank are full siblings from parental pair “A” and half the oysters are full siblings from parental pair “B”. For polycultures of three letters, a third of the oysters in the tank are from each respective parental pair; NA indicates this tank was not measured for shell height DiversityLevel: the number of genetic IDs represented in the tank (options include 1 (monoculture), 2 or 3 (polycultures)); NA indicates this tank was not measured for shell height Mono_Poly: tank assignment as to whether the genetic diversity is a monoculture (all direct siblings) or a polyculture (mix of multiple sibling groups); NA indicates this tank was not measured for shell height Salinity: the salinity group assignment (options include either low or meso); low is 5-10 ppt and meso is 15-20 ppt Oil: oiling category group assignment (options include none, oil, oil+dispersant) ShellHeight: measured shell height before the experiment began; shell height was measured from the umbo to the leading edge of the valve, in millimeters WholeWetWeight: weight of the intact oyster, in grams FoilWeight: weight of the piece of aluminum foil used to contain oyster samples in the drying oven, in grams FoilMeatWetWeight: weight of the foil and oyster tissue, in grams DryShellWeight: dry weight of the oyster shell after drying 48 hours on the counter, in grams FoilDryMeatWeight: dry weight of the oyster and accompanying piece of foil after drying 48 hours at 60 degrees Centigrade, in grams ACER_Oyster_WaterQuality.csv Date: MM/DD/YYYY calendar date the physical data was acquired with a YSI-2030 Time: HH:MM time, 24 hour clock, in Central Standard Time, that the physical data was acquired; blanks indicate there was no data taken System: the shelving system, which corresponds to one water treatment; water quality data was obtained from the sump tank of the shelving system SalinityGrp: the salinity group assignment (options include either low or meso); low is 5-10 ppt and meso is 15-20 ppt OilGrp: oiling category group assignment (options include none, oil, oil+dispersant) Temp: the measured water temperature in the sump tank, in degrees Centigrade Salinity: the measured salinity in the sump tank, measured in ppt ACER_Oyster_TPH_PAH.csv SampleID: unique identifier for the sample; the first two digits indicate the shelving system; the second set of letters and numbers indicates the time point; the last letter indicates the replicate CollectionDate: MM/DD/YYYY the date the water sample was collected and shipped to Pace Laboratories, LA TimePoint: the water sampling time point in the time series (options are 0-6) System: the shelving system, which corresponds to a water treatment; rows with an underscore followed by a number indicate the shelf within the system (only applicable for 1 hr and 24 hr time points in systems 2 and 3) Salinity: the salinity group assignment (options include either low or meso); low is 5-10 ppt and meso is 15-20 ppt Oil: oiling category group assignment (options include none, oil, oil+dispersant) TPH: concentration of total petroleum hydrocarbons, measured by EPA Method 8015M, oil range organics X2.Methylnaphthalene: concentration of 2-Methylnaphthalene, as measured by EPA Method 8270 Acenaphthene: concentration of Acenaphthene, as measured by EPA Method 8270 Acenaphthylene: concentration of Acenaphthylene, as measured by EPA Method 8270 Anthracene: concentration of Anthracene, as measured by EPA Method 8270 Benzo.a.anthracene: concentration of Benzo(a)anthracene, as measured by EPA Method 8270 Benzo.a.pyrene: concentration of Benzo(a)pyrene, as measured by EPA Method 8270 Benzo.b.fluoranthene: concentration of Benzo(b)fluoranthene, as measured by EPA Method 8270 Benzo.g.h.i.perylene: concentration of Benzo(g,h,i)perylene, as measured by EPA Method 8270 Benzo.k.fluoranthene: concentration of Benzo(k)fluoranthene, as measured by EPA Method 8270 Chrysene: concentration of Chrysene, as measured by EPA Method 8270 Dibenz.a.h.anthracene: concentration of Dibenz(a,h)anthracene, as measured by EPA Method 8270 Fluoranthene: concentration of Fluoranthene, as measured by EPA Method 8270 Fluorene: concentration of Fluorene, as measured by EPA Method 8270 Indeno.1.2.3.cd.pyrene: concentration of Indeno(1,2,3-cd)pyrene, as measured by EPA Method 8270 Naphthalene: concentration of Naphthalene, as measured by EPA Method 8270 Phenanthrene: concentration of Phenanthrene, as measured by EPA Method 8270 Pyrene: concentration of Pyrene, as measured by EPA Method 8270 Units: units of measurement for the analytes; crude oil is mg/kg and all others are mg/L

Methods:

Crude oil was mixed with seawater and it was sent out to the analytical lab for analysis to compare to our treatments. For oiled treatments, crude oil was added to the systems in a concentration of 1 ml of oil to 1 liter of water (1 ppt). For oiled treatments, this was 550 ml of oil added to the system. For oil+dispersant treatments, the same amount of oil was measured out, and mixed with 27.5 ml of dispersant, before being added to the systems. This is the recommended dispersant to oil ratio of 5 ml dispersant for every 100 ml of oil. Oil = Sweet Petroleum Crude Oil - MC 252 (Surrogate MC252 Oil, BP) Dispersant = Slickgone NS (Dasic International Ltd.)

Individual Files: