*3.1. North Captiva Historic Imagery*

Considering the Google Earth Pro historical coastline mapping, erosion on the northern portion of the island and a comparable sediment accretion on the southern end of the island can be observed consistently from 1994–2019. In 1994, North Captiva Island had a very narrow northern coastline (Figure 2) that widened moving south towards the mid-section of the island, narrowing again towards the very southern tip of the island. Since then, the northern portion of the island has experienced steadily increased erosion, with the southern portion after the landfall of Hurricane Charley has experienced steady accretion. While Hurricane Charley has had the greatest physical impact on the shoreline of North Captiva, other factors also have contributed to the changes in its morphology. Additional storms that hit the southwest Florida region such as Ivan in 2004, and more frequent winter storms also played a significant role in the shoreline evolution of this barrier island [13,14].

**Figure 2.** *Cont.*

**Figure 2.** Google Earth image of North Captiva Island, depicting coastline from 1994–2019, denoted by different colored paths. R-monuments are overlaid on map, R67–R82.

Sediment transport since the landfall and resulting damage of Hurricane Charley in 2004 is evident in the evolving coastline of North Captiva island, specifically the healing of the southern cut and overall widening of the southern tip. By 2008, the southern portion of the coastline was consistently widening, showing the greatest width post-Charley by 2019. The modern coastline of North Captiva Island fits into this sediment transport pattern as well, as the island continues to erode in the north and widen in the south from sediment transport via longshore currents where the breach once was [7].
