Table 1.
Summary of all past and current blue crab winter mortality laboratory experiments.
Units for temperature are in °C, salinity is in psu, duration is in days, and carapace width is in mm. The design indicates what covariates were used in the experiment. (Sal = salinity, Temp = temperature, Sed = sediment).
Fig 1.
Kaplan-Meier survival curves by sex.
Solid lines show the KM survival curves for females and males in black and grey, respectively. The dotted lines indicate confidence intervals.
Fig 2.
Kaplan-Meier survival curves by size class.
Crab cohort classification is based on the following sizes: Large > 60 mm, medium ≤ 60 mm and > 30 mm, and small ≤ 30 mm. KM curves for large crabs are in black, medium crabs are in gray, and small crabs are in red.
Fig 3.
Percent mortality calculated for crabs from all three experiments in 10 mm size bins. The numbers above each bar indicate how many individuals are in each size bin.
Fig 4.
Histogram of crab sizes used in experimental year 2 (2017).
Black bars show the number of crabs used in the 2017 experiments from CB in 10 mm size bins, and gray bars show the number of crabs from GSB.
Fig 5.
Kaplan-Meier survival curves for CB and GSB in experimental year 2 (2017) by size class.
In every panel, the colors correspond to bay, solid lines represent KM curves, and the dashed lines are confidence intervals. Black indicates GSB crabs and grey is for CB crabs from just the 2017 experiments. (A) All sizes (B) large > 60 mm (C) medium ≤ 60 mm and > 30 mm (D) small ≤ 30 mm.
Fig 6.
Observed and predicted survivorship for the 10 treatments from this study and the 4 treatments from Bauer and Miller [52].
Kaplan Meier estimators of the observed data for each temperature and salinity treatment combination are shown in the step-like black line for both Chesapeake Bay and Great South Bay crabs from the present study, and in red for the observed data from Bauer and Miller [52]. The solid lines show predicted model fits for three different models, using average values of temperature, salinity, and carapace width (mm) from each treatment as the predictive variables in the model. The text above each panel indicates the experimental temperature and salinity level for that treatment. Panels B, D, K, and N, which are outlined with a thick box, show data from [52] while the rest are data from our experiments (A) Temperature = 2 °C and salinity = 5 psu, (B) Temperature = 3 °C and salinity = 10 psu, (C) Temperature = 2 °C and salinity = 20 psu, (D) Temperature = 3 °C and salinity = 25 psu, (E) Temperature = 2 °C and salinity = 35 psu, (F) Temperature = 4 °C and salinity = 5 psu, (G) Temperature = 4 °C and salinity = 15 psu, (H) Temperature = 4 °C and salinity = 20 psu, (I) Temperature = 4 °C and salinity = 30 psu, (J) Temperature = 4 °C and salinity = 35 psu, (K) Temperature = 5 °C and salinity = 10 psu, (L) Temperature = 6 °C and salinity = 15 psu, (M) Temperature = 6 °C and salinity = 30 psu, (N) Temperature = 5 °C and salinity = 25 psu.
Table 2.
Model selection criterion for the top 10 performing models using all of the data, including crabs from Bauer and Miller [52].
Table 3.
Parameter estimates from the best AFT model using all available data, including crabs from Bauer and Miller [52].
Fig 7.
Survival estimates at 100 days of winter for an average sized crab from the exponential model over a range of temperatures and salinities that may be experienced in winter.
The values for each point were calculated from the exponential model by inputting time, the average carapace width of crabs from all experiments, temperature, and salinity. The results are plotted as survival probability vs. temperature. Each colored curve represents a distinct salinity level.
Fig 8.
Survival estimates at 100 days of winter from the exponential model over a range of temperature and salinities that may be experienced in winter.
The values for each point were calculated from the exponential model by inputting time, a representative carapace width for that size class, temperature, and salinity. Expected survival probability is shown on the z-axis and in the color of the contoured surface. Each panel shows the expected survival for an individual from one of the three size classes (A) Small: CW = 20 mm, (B) Medium: CW = 50 mm, (C) Large: CW = 100 mm.