Growth rates of the earliest juvenile stages of sessile marine invertebrates

The earliest, newly settled juvenile stages are a critical phase in the life cycles of sessile marine invertebrates. Individuals must grow quickly to avoid lethal predation, yet they may be stuck in low flow boundary layers where obtaining food for rapid growth is challenging. Newly settled zooids growing with little to no competition on PVC plates were measured. I tested for rate variation from earliest juvenile stages with fine scale measures of surface area and zooidal numbers in two non-native taxa with contrasting internal and external feeding structures. Growth rate variation was observed for specific growth rates at the varied environmental conditions in field environments (marinas). Overall, this data may be used to consider if the most successful invaders show a growth rate advantage particularly at the earliest and most vulnerable stages in the life cycle.