In 1990 Readex Readership Research conducted a wide-ranging survey of this magazine's readers. We asked readers what topics they wanted to know more about. The top choice of most: habitat preservation. Later surveys have shown abiding interest in habitat.
This issue is all about habitat—lakes and rivers, being invaded by aggressive nonnative species; northern forests, being surveyed for breeding bird populations; wetlands and uplands, being protected and restored with citizen dollars.
Being creatures of habitat ourselves, we appreciate the need for a place with food and water, shelter and space to survive. The survival link between habitat and organism is undeniable. Yet the complexity of interactions—including our connection to natural communities—requires continuing examination.
One of the first to study the relationship of creatures and ecosystems was a young forester working in New Mexico in the early 1900s. Unlike most of his contemporaries, Aldo Leopold came to think that removing bears, wolves, and other predators from the national forest broke vital links in natural communities. Eventually, his ideas on interconnectedness became a basis for fish, game, and land management. His book A Sand County Almanac, published in 1949, remains a guiding text for natural resources use and conservation.
Where creatures choose to live depends in part on their habitat preferences. "The Ways of Warblers" nicely illustrates the choices of various wood warblers. Author Marshall Helmberger tells how to associate a warbler with its breeding and nesting habitat. What are the dominant tree species? Are they young or old? Growing on a hill or in a swamp? If you recognize the habitat where you are, you can more easily identify the species you're likely to see there.
It's also helpful to know where in a particular place a certain species would choose to hunt, hide, feed, rest, and nest. In other words, how do a bird's traits match up with landscape features? What might a bird look for in a habitat? For example, because an ovenbird nests on the ground, it will look for dense understory in the forest. In her book Northwoods Wildlife: A Watcher's Guide to Habitats, Janine Benyus gives a rundown of considerations, including habitat size, structure (vegetation shape, height, density, diversity), vertical and horizontal zones, openings and edges (where field meets forest, for instance).
In "Ups and Downs of Forest Birds," researcher Gerald Niemi reports on the findings of two decades of breeding-bird population surveys in Chippewa and Superior national forests. Driving the concern for bird population status conerns the forest's condition. Has loss, fragmentation, or another alteration of habitat had an impact on an entire species?
Given a bird's remarkable ability to fly (explained in "How Do Birds Fly?"), we might imagine a displaced bird could simply relocate to more suitable habitat. A recently published University of Connecticut study looks at what could happen if climate change makes a species' natural habitat inhospitable. Dispersing birds could be competing for space and resources in already claimed niches.
Competition for occupied territory is the hot topic discussed in "Stop the Invaders." With the arrival of each nonnative plant and animal species in a Minnesota lake or river, the native aquatic community changes. What happens if a new species is invasive, that is, if it spreads aggressively? At an extreme, the interactions could lead to local extinctions. People have pivotal roles in how these scenarios play out. Our actions can cause or prevent the spread of aquatic invasive species. Our good habits help protect critical habitat.
Minnesota citizens have long advocated for protecting critical wildlife habitat. "RIM Revival" shows how conservationists crafted a program 25 years ago to put state fishing-and-hunting dollars into saving, improving, and restoring habitat. "Holy Cow! More Land for Sharptails" highlights a case of Legacy amendment dollars spent to secure grassland.
If MCV readers were asked to name Minnesota's top conservation concern today, I'm pretty sure most of us would say it's the habitat—and up to each of us to defend.
Kathleen Weflen, editor