Population Growth on Barrier Islands

Level of Indicator: I
Type of Indicator: B


Explanation of Indicator
Barrier islands are made up of loosely compressed materials (mostly sand) and are vulnerable to forces of wind, waves, sediment transport, the effects of hurricanes, and sea level rise. Most barrier islands can be characterized as low-lying and highly susceptible to coastal flooding. These islands are comprised of different and distinct ecosystems; some of these ecosystems include dunes, wetlands, maritime forests, and salt marshes. Barrier islands serve many social and natural functions: they are the first line of defense against hurricanes and coastal storms; they provide enclosures for estuaries and marshes; they are home to a variety of plant and animal life; and they provide considerable recreational and aesthetic benefits.1

Population growth on barrier islands is an important indicator because human-made development can threaten the quality of the already fragile environment. Monitoring population growth will help policy makers document the impacts of development on these islands and aid in planning future development. The primary threats to the human population of barrier islands are hurricanes and coastal storms. Monitoring population growth will help in making disaster and evacuation plans for these islands.

Data Characteristics
SOURCE
This information is available from Steve Grantham, Florida Department of Community Affairs, Division of Emergency Management, 2740 Centerview Drive, Tallahassee, Florida 32399-2100, or at (904) 413-9891.

ACQUISITION
The data are available in hard copy format and as Geographical Information System files. The cost for obtaining this information is approximately $80 per hour. Compiling the data will require eight to sixteen hours of work. If plots are produced, an additional 24 hours or work will be necessary.

COLLECTION
The data are collected by census tract every ten years. Population is estimated for the years in between census updates. The data are collected for the entire state, but can be broken down by county and census tract.

Data Limitations
These data are the best available for this indicator. The limitations associated with the data are the same limitations inherent in census data. The collection methodologies and analysis of the population figures may lead to some double counting, undercounting, or misrepresentation. Another problem in working with data at the census tract level is that a census tract may extend from a barrier island into the mainland, thereby including population which is not restricted to the barrier island itself.

Recommendations
Given the availability of the data, the Florida Coastal Management Program should work with the Division of Emergency Management to obtain and compile this information. Data should be collected annually, by county. Because barrier islands tend to be located directly off the coast and consist of relatively small land areas, data collection by county should not be difficult. Once the data are collected, they should be entered and stored in files using the Geographic Information System.


1Timothy Beatly, David J. Brower, and Anna K. Schwab, An Introduction to Coastal Zone Management, Washington D.C., Island Press: 1994.