In my previous two posts I have been discussing a study by Radeloff and 7 others. It showed that the number of housing units in or near protected natural areas have increased at a faster rate than the number of housing units in the United States as a whole. Housing doesn’t have to be inside a protected area to have a detrimental effect on it. See my two previous posts for the details.
That development has occurred in or near protected lands should surprise no one – for instance, many people are aware that ski resorts have developed in or near protected lands: Aspen, Vail, Keystone, Breckenridge – the list is quite long.
On the other hand, protected lands have expanded greatly since 1940, and this leads to a caution that needs to be considered in using data from the Radeloff et al. study. Wikipedia lists 34 national parks and 9 national forests that have been created since then. For instance, Joshua Tree National Park was established in 1994. Suddenly the entire Coachilla Valley – Palm Springs, Palm Desert, La Quinta, and so forth – came within 50 km. of a national park. Saguaro National Park was also established in 1994. Suddenly Tucson came within 10 km. of a national park.
The entire wilderness system wasn’t established until 1964, and the Bureau of Land Management wasn’t required to review their land for inclusion in the wilderness system until the Federal Land Policy and Management Act of 1976. These two acts resulted in the creation of hundreds of wilderness areas, consisting of millions of acres. Some of this land was previously in other federal land protection programs, but not necessarily the ones looked at by the Radeloff et al. study.
To what degree do the changes that the study discovered reflect the growth of housing near protected areas vs. the growth of protected areas near housing? Personal communication with Dr. Radeloff indicates that land records were not adequate to allow them to control for changes in the boundaries of the protected lands they studied.
The Mark Twain National Forest was established in 1939. However, 7 wilderness areas lie within its boundaries. The Radeloff et al study does not report data by state or by specific protected area, so we don’t really know whether housing growth near Missouri’s protected lands reflects national trends.
Either way, the detrimental effect that housing would have on protected areas would not depend on whether the housing invaded the protected land or vice-versa. In either case, the ability of the protected land to provide its “Noah’s Ark” function, to provide essential ecological services, would not be fully intact.
Radeloff, V.C., Stewart, S.I., Hawbaker, T.J., Gimmi, U., Pidgeon, A.M., Flather, C.H., Hammer, R.B., and Helmers, D.P. (2010). Housing Growth in and Near United States Protected Areas Limits Their Conservation Value. Proceedings of the National Academy of Sciences, 107, (2), 940-945, http://www.pnas.org/content/107/2/940.full.pdf+html.
List of National Parks of the United States, Wikipedia, http://en.wikipedia.org/wiki/List_of_national_parks_of_the_United_States.
List of U.S. National Forests, Wikipedia, http://en.wikipedia.org/wiki/List_of_U.S._National_Forests.
National Wilderness Protection System, Wikipedia, http://en.wikipedia.org/wiki/National_Wilderness_Preservation_System.
Mark Twain National Forest, Wikipedia, http://en.wikipedia.org/wiki/Mark_Twain_National_Forest.