The Legislature, agencies, and organizations provide laws, rules, and guidelines for recreationists, but , it is essential that recreationists also undertake voluntary stewardship activities. To help conserve wildlife habitat, they must recognize that their activities affect landscape features and species and act in a manner that minimizes or eliminates adverse effects. See the Social & Economic Overview for more information about non-consumptive recreation and observed trends. The following test discusses issues of concern that can occur as a consequence of non-consumptive recreational activities.
Recreational activity can significantly disturb soils. The degree of disturbance depends on a variety of factors, such as soil type, slope, and manner and intensity of recreational activity. Sandy or wet organic soils can be negatively affected by a one-time activity, whereas heavy clay or gravel sites can withstand heavier activity. Given the same soil type, the effects of a single pass of an ORV can also be caused by hikers over an extended period.
Soil erosion is the most commonly identified threat resulting from heavy recreational use. Erosion is most pronounced when soils are particularly susceptible to damage or erosion, or when recreation intensity is high. Dunes are particularly vulnerable because of their sandy soils and low organic content. The vegetation that holds dunes in place is easily damaged. Recognizing potential for damage, many public areas have constructed boardwalks and other trail improvements. Particularly sensitive areas include steep slopes, vegetated rocky areas, wetlands and riparian areas. On steep slopes, eroded areas often channel water from rain storms and cause increased erosion, which may damage large areas of vegetation. As soil from affected sites begins to erode, it can flow into nearby waterways, increasing sedimentation (see Altered Sediment Loads).
Recreational activities can literally squeeze air out of spaces that typically surround soil particles by compacting soil, resulting in reduced water retention within the soil, reduced water and nutrient uptake by plants, reduced availability of oxygen and other gases used in respiration, and prevention of plant root spreading. Exposure of plant roots as soil is compacted or eroded around them, and subsequent damage, can make trees more susceptible to wind by affecting their anchoring ability, by impeding nutrient flow through the roots, and by providing a conduit for insects or disease. Compacted soils can also deter tunneling of fossorial animals. Each of these effects can lengthen the normal recovery of a site by keeping it open and vulnerable to additional damage.
Introduction and Spread of Invasive Plants
Recreational vehicles and even hiking boots can transport soil containing invasive plant seeds to unaffected sites. It is suspected that some purple loosestrife stands were established in this manner (M. Penskar, personal communication). Seeds can also be transferred when attached to clothing or when ingested by horses and transported in their manure. Eurasian milfoil, zebra mussels and many other invasive species can be transferred to unaffected waters by boats and in bait buckets. Veligers and young zebra mussels can survive temporarily out of water. Eurasian milfoil can reestablish itself by vegetative propagation of plant stems. Non-consumptive activities that remove or trample native vegetation can further promote the spread of invasive species by reducing competition and providing opportunities for new establishments.
Direct Threats to Wildlife
Some reptiles use exposed trails for sunning, making them more susceptible to direct mortality from recreational traffic. Continuous use of avian nesting areas or intentional harassment by outdoor recreationists can cause indirect mortality through brood abandonment. For example, beach use on Great Lakes shorelines by ORVs and humans has frequently caused adult Piping Plovers to abandon nests and broods. On inland lakes, nest and brood abandonment by Common Loons has been observed in response to heavy boating activity. As a preventative measure, the DNR commonly closes Piping Plover and Kirtland's Warbler nesting sites to humans to reduce the potential for nest site disturbance. ORV traffic through streams can directly destroy fish nesting areas or damage nests downstream through increased sedimentation.
Winter is a critical time for many species; energy is directed at a few essential activities. Repeated disturbance by non-consumptive recreational activities can cause organisms to expend reserved energy and reduce their likelihood of successfully surviving through winter. Bats hibernating in caves are particularly vulnerable to repeated disturbance.
Conservation Needs to Address Non-Consumptive Recreation Threats:
Land, Water & Species Management