These laboratory data for estimates of change in fertility and survival rates observed relative to control (unexposed) conditions for fundulus heteroclitus exposed to varying levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin including 112, 296, and 875 pg/g are relative rates, and thus they are unitless.
The data for observed survival and fecundity by age and size for populations of fundulus heteroclitus that were considered unexposed to chemical stressors contains the following units: survival rates are fraction surviving per year and fecundity rates are eggs per year.
This dataset is associated with the following publication:
Miller, D., B. Clark, and D. Nacci. A multidimensional density dependent matrix population model for assessing risk of stressors to fish populations. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY. Elsevier Science Ltd, New York, NY, USA, 201: 1-8, (2020).