Last winter I read a book written by a young biologist named Emma Marris called "The Rambunctious Garden." It was not about gardening in gardens, but rather a new way to look at the management on natural areas. The first part of the book very methodically whacked away at some of the basic underpinnings of conservation work that I have held dear. I squirmed my way through this occasionally thinking defensive thoughts. The second part talked about solutions and a new way of looking at things.
The concept that Emma most effectively whacked was that of the "baseline." I grew up reading about the glories of the wild continent that the pioneers found. Of immense forests of giant trees, long prairies full of bison and elk, and clear streams full of fish. In Ohio all that was pretty much lost my the mid 1800's, and most of the nooks and crannies were "lost" by the mid 1900's. Ever since starting with the Park District in 1985 I have labored to protect land and restore it to some fraction of its former splendor. The land itself is a collage of land and soils highly disturbed by agricultural or other human activity, land and soils somewhat disturbed, and land and soils lightly or very lightly disturbed. We have always tried to manage for a diversity of habitats following principles of conservation biology: bigger is better, connected is better, fire is a good tool. In retrospect we have succeeded best by managing for structure. That means designating where forests, grasslands, thickets, and wetlands will be protected or established. That's a challenge right there. The further one tries to dictate the composition of these communities the tougher it is. If the 1800 baseline is the goal, then success is only achieved when the species that were present then have returned and the non-native interlopers have been eradicated. I know plenty of people who will be miserable in a forest or meadow crackling with life because it does not meet this goal. Emma points out that the goal was folly in the first place:
- Nature was not standing still then, it had always been changing. We just weren't there to see it.
- People have shaken the earth up like a snow globe moving species all over the planet. These newcomers are often more suited to do well in a heavily disturbed environment than the locals.
- "Pristine" areas that have minimal disturbance are still heavily impacted by the disturbed lands around them.
- Climate change is further modifying the world making the baseline even more irrelevant.
All this does not mean one gives up, or that our actions are not important. It means we should float downstream instead of fighting up through impossible rapids. In southwest Ohio most of our protected land is what is what is now being called a "novel ecosystem." They are mutts of native and non-native species. There is no putting Humpty-Dumpty together again the was he was. The new Humpty can be pretty cool though. The bobolink sings in a field of eurasian grasses and weeds. The Coopers Hawk nabs European house sparrows at the feeder. The woodpeckers love Emerald Ash Borer larva. All of them seem to be more adaptable than many biologists and land managers (like me.) Perhaps some new principles to live by:
1. Identify those areas that continue to maintain pre-settlement biodiversity. Prioritize action against invasive species there. However, they will only maintain themselves as-is if the processes that maintain them remain.
2. Accept new components to habitats on heavily disturbed sites. This might sound like surrender, it is really just being realistic. Manage them for structure and don't worry so much about their exact composition.
3. Teach children and upcoming biologists that these new novel habitats are important and beautiful. After all, it is most of the world that we now live in.
4. Promote native species, but don't go for an impossible baseline.
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