On the beach, sea lavender, beach star and other rare native plant species thrive. Along the ocean shoreline, brown pelicans, terns, sandpipers and other shorebirds may be seen resting and feeding. MacArthur Beach is also a prime nesting area for sea turtles. Large numbers of loggerhead, green and leatherback turtles nest in the park from early May through late August. Inquire about Ranger-led walks to search for nesting loggerheads in June and July.
Marine life is abundant along the offshore reefs and rock outcroppings within the park.
These spectacular natural features, easily accessible from shore, make snorkeling a popular activity in the shallow waters. Because it is a natural barrier island, the park also protects the mainland from harsh ocean storms. Shifting beach sands absorb wind and wave energy. To keep the area as natural as possible, roads and structures were designed around rare trees and other plants. Non-native species, such as Australian pine and Brazilian pepper, are removed.