Wildlife by populations
Populations of many wildlife species have increased since the environmental legislation of the 1960s and 70s. While success stories increase, there's a significant number of species on the endangered and threatened lists at both state and federal level.
The United States has a rich history of wildlife conservation. The Lacey Act (1900) was the nation’s first legislation to protect wildlife and addressed trafficking and trade. The Migratory Bird Treaty Act was enacted in 1918. The Endangered Species Act came along in 1973. Professional wildlife managers first formally defined the North American Model of Wildlife Conservation in 2001, although the tents of the model go back to the late 1800s.
Michigan sports 550-600 vertebrate wildlife species, then thousands of invertebrate species. Vertebrates are animals with backbones. Many of these birds, fishes, mammals, reptiles, and amphibians have made dramatic comebacks due to environmental protection laws, forest and wildlife management, and habitat recovery. Frankly, many of these species population trends are unknown and can only be inferred through knowledge of their habitat preferences, and how that habitat has changed over the decades. Tracking habitat diversity is far more expedient than research into hundreds of wildlife populations. Despite a large number of recovery success stories, there remain many animal species on federal and state endangered species lists, most of them shellfish and insects. In Michigan, there are about 123 species on endangered and threatened lists. Then another 160, or so, on the special concern list. About 32 Michigan wildlife species are on the federal lists.
Part of the reason that numbers of listed species increase is because we are looking for them. The biological sciences have exploded over the past fifty years. However, the relentless human expansion into wildland areas comes with costs to some species of wildlife. Even the nearly century-long growth of forest area and volume is expected to peak and reverse within the next couple of decades. For many decades, hunters and fishers have been the largest financial supporter of wildlife management through license fees as well as special federal taxes on hunting and fishing equipment. Some of the relevant enabling legislation includes the Pittman-Robertson (1937) and Dingell-Johnson (1950) Acts. These taxes raise more than $60 million per year for Michigan and Wisconsin. Game species have been the primary focus, although many non-game species have also benefitted from these revenue sources. While $60 million is a lot in a personal bank account; it really is not much in the world of wildlife management. We spend more money on pizza.
As for habitat, the majority of northern vertebrates (including fish!) utilize forests for at least part of their requirements. Foresters have long managed forests for a diversity of composition and structure. Over the past century, forests continue to recover from the historic logging era, albeit with a different set of forest conditions. Forests cover about half of Michigan and a third of Wisconsin. Forest area and volume in Michigan and Wisconsin have been steadily growing since the historic logging era.
Other habitat types have fared less well than forests. Wetlands are somewhat stable at a reduced area, although quality is an issue. Prairies, savannahs, certain wetlands (e.g. fens), shrub-scrub lands, riparian forests, and young forests are among the less common or otherwise special habitat types. Wildlife closely associated with these habitats are in decline or of concern.
The dynamics of wildlife populations and their relationships with habitat and humans has a long and complex history. Their future will likely be at least as interesting as their past.