Chapter 5 Threats
An example of human intrusion and disturbance impacts on wildlife is the effect of pedestrian and vehicular traffic on nesting shorebirds and sea turtles along North Carolina’s Outer Banks. Several species of shorebirds, such as Piping Plover, American Oystercatcher, Black Skimmer, and Least Tern, nest on beaches at the Outer Banks each year. Sea turtles lay eggs in nests on North Carolina beaches each year. Pedestrian traffic can reduce reproductive success for nesting shorebirds such as Least Terns (Kanapaux and Kiker 2013) , American Oystercatchers (McGowan and Simons 2006; Sabine et al. 2008,) and Piping Plovers (Doherty and Heath 2011) . Nesting shorebirds can be impacted by the frequency, duration, and proximity of pedestrians. Vehicular traffic can also reduce reproductive success or reduce hatchling survival of nesting shorebirds (McGowan and Simons 2006; Tarr et al. 2010) . The impact of pedestrian traffic and vehicular traffic can be mitigated by establishing buffers around nesting shorebirds and controlling the locations and timing of beach driving. Among the features that make beach habitats suitable for sea turtle nesting are accessibility from the water, being situated high enough above the active surf zone that sand is not constantly inundated by high tides or the water table below (Mortimer 1982; Miller et al. 2003) , and lack of artificial structures and visible lighting (Witherington 1992; Bouchard et al. 1998) . Excessive nighttime lighting from buildings or vehicles can render nesting beaches unsuitable or unused because lighting disorients the sea turtles, thereby reducing the number of female sea turtles nesting on North Carolina beaches (Witherington 1992) . Sea turtle hatchlings generally emerge from their nests at night and rely on visual cues for successfully finding and entering ocean waters (seafinding behavior) (Ehrenfeld 1968; Mrosovsky and Shettleworth 1969) . When exposed to sources of artificial light, seafinding behavior of hatchlings will become disrupted, and often hatchlings will travel away from the sea (Peters and Verhoeven 1994; Philibosian 1976; Salmon et al. 1995a, b) , which increases the time they are exposed to land-based predators, reduces the amount of residual internalized yolk available to hatchlings for their initial swim offshore, and could result in desiccation/death if the hatchlings remain on land after sunrise. Driving motorized vehicles on the beach has the potential to negatively impact sea turtles by running over nesting females, hatchlings, and stranded turtles that have washed ashore. Driving directly above incubating eggs in a sea turtle nest can cause sand compaction, which results in decreased hatching success and can kill pre-emergent hatchlings. In addition, the ruts left by motorized vehicles in the sand may prevent or impede hatchlings from reaching the ocean following their emergence from the nest (Hosier et al. 1981; Lamont et al. 2002; van de Merwe et al. 2012) . Reducing artificial lighting and nighttime beach driving can increase the number of female sea turtles nesting on our beaches. Marking sea turtle nests and creating protective buffers around nests can prevent nest disturbance. Limiting vehicular traffic during sea turtle emergence can prevent direct mortality and prevent tire ruts that can impede hatchlings as they travel to the ocean.
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2025 NC Wildlife Action Plan
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