Submitted by Sammy Smith (firstname.lastname@example.org)
When humans enter an ecosystem, they displace some species and prey upon others. This is true of both plants and animals, including species most of us don’t really notice (for example, nematodes in soil and rotifers in freshwater).
As human populations increase, and peoples intensify occupation of the environment (demographically, populations become denser), demands on environmental resources increase. The impacts of displacement and predation increase. They must; more people mean demands for food, shelter, and other material goods increase.
In the Great Plains of North America, bison populations have decreased over the last two centuries—a response to increasing human populations and the consequences of that proliferation.
The International Union for Conservation of Nature is “a democratic membership union with more than 1,000 government and NGO member organizations, and almost 11,000 volunteer scientists in more than 160 countries” (according to the IUCN website). In early March 2010, the IUCN released a report called American Bison: Status Survey and Conservation Guidelines 2010. The report discusses the current status of the American bison (Bison bison).
The American bison ranged across the Great Plains in large herds, browsing on the vast prairie grasslands. Notes the report, “there is little doubt that prior to Euroamerican settlement, plains bison numbered in the millions, and probably even in the tens of millions” (page 8).
Through the late 1800s, bison herds were hunted commercially, to “open” lands for colonization by peoples from the east. There was also sport hunting. Environmental factors, including introduced bovine diseases, also reduced bison populations. Their numbers became so diminished that in 1905 the American Bison Society was formed and sought to establish bison herds at several federal landholdings (page 9).
Chapter 2 of the report, downloadable from this webpage, discusses bison prehistory and history, including the species’ original range. On page 11, the report notes:
With increased resolution and clarity afforded by ethnohistoric and ethnographic investigations, human-bison interactions among historic native peoples are better described and documented than for the late Pleistocene and Holocene. Bison continued to be the preferred game for many native North American cultures, especially on the Great Plains and Prairies, providing food, clothing, shelter, and tools…. Sustained by bison and plant resources, many native groups likely affected densities of other large herbivore species…. In addition to significant ecological relationships, the bison was a central element in oral tradition, rituals, dances, and ceremonies of native peoples of the Plains…, and it remains symbolically important in the cultural traditions of many native Tribes to this day.
The arrival of Europeans in North America, after 1492, resulted in significant changes in human-bison interactions, and changed the fabric of Native American life forever. Introduced diseases such as smallpox decimated indigenous human populations…, and altered subsistence, settlement, demography, and social organisation for many different groups. Bison hunting by native people was seasonal in nature. Bison were incorporated into a broad spectrum of plant and animal procurement activities…. Bison provided the economic basis for stable, resilient land use regimes and social systems. However, effects of Native American warfare and raiding during the historic period disrupted and destabilised these land use and social systems. The spread of horses into Great Plains aboriginal economies by the 1750s, and increasing commoditisation of bison products caused by the emergence of a European commercial market for wildlife products by the 1820s, contributed to the near extinction of the bison…. Native peoples traded bison hides for Euro-american commodities, with the market in bison robes reaching a peak in the 1840s. Hide hunters began to significantly participate in the market hunting of plains bison in the 1850s, and by the 1890s had decimated the herds. Even bones were cleaned for sale to the eastern fertilizer market, an activity that continued to 1906….
The bison is now extirpated from its original range across North America. Extirpation is a word ecologists use to refer to a species that no longer exists naturally in a particular area. In the case of the American bison, it no longer roams wild across an unlimited range, so it is considered extirpated—although it is not extinct. Extinct, in this context, means individuals of that species no longer exist.
Now, however, modern land use, including roads, communities, fields, and fenced pastures, mean that today’s bison cannot roam and graze as they did prior to this development. As the IUCN report notes:
Bison can best achieve their full potential as an evolving, ecologically interactive species in large populations occupying extensive native landscapes where human influence is minimal and a full suite of natural limiting factors is present. While such conditions remain available in the north of the continent, it is challenging to find extensive landscapes for restoring and sustaining large free-roaming wild bison populations in southern, agriculture-dominated regions. [page 2]
In the final summary, the report concludes:
The next 10-20 years present opportunities for conserving American bison as a wild species and restoring it as an important ecological presence in many North American ecosystems. Taking an ecosystem approach, which puts people and their natural resource use practices at the centre of decision-making, offers a paradigm for balancing the sometimes competing demands of bison conservation, the use of bison and biological diversity by people, and sustaining human communities in areas where there are many resource users combined with important natural values. To achieve ecological restoration at broad scales (large herds roaming across vast landscapes, at numerous locations) will require flexible approaches that can be adapted to a variety of legal and socio-economic conditions. Assembling large landscapes for conservation herds will typically involve several land tenure holders, potentially including public agencies, tribal governments, non-profit private organisations, and for-profit corporations or individual entrepreneurs. Diverse mandates, interests, and incentives will influence how stakeholders choose to manage land and wildlife, including bison. Creative new approaches are needed for forging enduring partnerships among land tenure holders for cooperative undertakings. Strategies may range from top-down government programmes to bottom-up market-based or cultural-based initiatives. Progress towards large-scale restoration will require a much more supportive framework of government policies and significant investment by both public and private sectors. Awareness and substantial public support are necessary at both the local level where restoration occurs, and among national constituencies for whom the bison is an iconic component of North America’s natural and cultural heritage. For ecological restoration of bison to be successful, careful assessment and understanding of biophysical, social, economic, legal, and political conditions are required for planning and implementation. This is particularly true where both community and agency support and involvement are required. This chapter provided guidelines for planning and implementing an ecological restoration project for bison, including feasibility assessment, selection of stock, preparation and release methods, assessing socio-economic and legal requirements, monitoring, evaluation, and adaptation. [page 112]
Although viable preservation of the species is the focus of the IUCN report, it also provides a good summary of the past of the American bison in North America, including a review of our understanding of human occupation of the Great Plains. Bison are known archaeologically from the Southeast, and bison trails are commonly believed to have been been incorporated into networks of human foot-trails (which later became the routes of roads and railroads).
Why do you think bison trails would have been used by humans?