Chantel Elston

1 INTRODUCTION Marine predators can play important roles in coastal ecosystems by exerting top–down effects on prey through consumptive and non-consumptive interactions (i.e., predation and fear-based effects) and simulating bottom-up processes by transferring nutrients across ecosystem boundaries (Heithaus et al., 2008; Matich et al., 2017; Papastamatiou et al., 2015).

1 INTRODUCTION Migration in ocean ecosystems is a widespread phenomenon in multiple taxonomic groups such as marine mammals, reptiles, teleost fish, and elasmobranchs. This regular movement from one location to another is often adaptive in nature and is in response to either internal mechanisms, for example, breeding behavior, or environmental ones, such as changes in water temperature or food availability (Bauer & Hoye, 2014; Shaw, 2016).

Many factors contribute to the formation of HABs, such as nutrient loading and increased water temperature. Due to growing anthropogenic development and global climate change, these two contributing factors are on an upward trend and thus HAB events are likely to be more frequent. The IRL is an “estuary of national significance”, which serves as a spawning and nursery ground for many fish species, including elasmobranchs.