## 4 Discussion
### Conservation Implications  
Much of the land cover change occurring in the RCR over the past few decades is due to successional processes. However, these maps show the result of geophysical drivers that are continuing to shape Bird Shoal as well as the potential impact of sea-level rise (SLR) on saltmarshes in this area. Succession is best evidenced by the conversion of herbaceous and scrub-shrub habitat to forest, and the colonization of intertidal sandflats by saltmarsh vegetation. Examination of the supratidal sand component reveals a long-term pattern of sediment redistribution within the RCR. For the past decade, the supratidal component of Bird Shoal has been steadily growing as nearby Beaufort Inlet has been widening. Prevailing winds occur from the southwest, and several tropical cyclones have directly impacted the study area during this time, including Hurricanes Ophelia, Irene, Arthur, and Matthew, which together appear to have resulted in overwash and longshore delivery of sediments, extending the island to the east. Because of the sheltered nature of fetch-limited barrier islands, storm overwash has significantly reduced return energy, resulting in primarily landward movement of the beach [58], and nearshore wave refraction is decreased, yielding greater alongshore transport of sediment [31]. Overwash and aeolian transport across sparsely vegetated areas have delivered sediment to the low relief area between Bird Shoal and Town Marsh, increasing the elevation and providing suitable habitat for saltmarsh vegetation to colonize [59; 60]. Thus, we see substantial increases of intertidal emergent wetland habitat in the western third of the RCR. This expansion of Bird Shoal has also encroached on other areas of the RCR, with the island migration rolling over emergent wetlands and now bleeding into Horse Island. With SLR, the migration of Bird Shoal will likely continue, eventually overtaking Horse Island and narrowing the low-lying intertidal wetlands between the outer shoreline and the dredge spoil mounds on the north side of the RCR. The speed at which this migration occurs will depend on the island's recovery, the continued impact of Beaufort Inlet dynamics, future storm activity, and the rate of local SLR. Changes in the extent of different habitat types may have implications for the management of living resources within the RCR. The RCR represents important seasonal habitat for several endangered species of plants and animals [61], and is also home to a stable population of feral horses that exert both direct and indirect effects on the local estuarine ecosystem [62]. As these habitats evolve, conflicts amongst management priorities may emerge [63], and the workflows provided in the present study provide an initial framework for RCR managers to efficiently monitor habitat change and plan for such conflicts. Island movement within the RCR in response to storms and inlet changes is likely compounded by the occurrence of higher water levels within the past decade. Interaction of the North Atlantic Oscillation and the El Nino Southern Oscillation have caused hotspots in local SLR along the US East Coast since 2011 [64], and the region has experienced periods of frequent sea-level anomalies [65; 66]. Higher water levels can result in more rapid sediment erosion or accretion depending on the forcing patterns [67] and whether the shoreline has already been compromised by a recent storm [66]. Increased water levels may be contributing to the loss of emergent wetlands in the eastern portions of the RCR (Carrot Island, Horse Island, and Middle Marsh), as increased inundation leads to greater marsh bank erosion and saltmarsh die off in the lower intertidal [68; 69; 70]. Being linked to atmospheric-oceanic cycles, the area will experience periods with lower rates of SLR, which may allow some recovery of emergent wetlands.