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“Naturalness” in designated Wilderness: Long-term changes in non-native plant dynamics on campsites, Boundary Waters, Minnesota

Wilderness areas in the United States are preserved for their untrammeled naturalness and opportunities for unconfined recreation. The Boundary Waters Canoe Area Wilderness has these qualities, but long-term recreation visitation pressures on campsites can cause significant ecological changes. This article explores changes on campsites, specifically examining non-native plant ecology over 3 decades. The research replicates a 1982 study analyzing vegetation composition and cover on campsites and environmentally paired controls. Camping activities have removed substantial tree cover on campsites, altering their ecological conditions and perceived wilderness character. Over the span of 32 years, the number of non-native plant species found on campsites has not risen, although their mean relative cover has increased significantly and they have spread to more sites. Of the 23 non-native herbs and grasses found on the campsites, only Cirsium arvense is considered a noxious weed by the state of Minnesota. Other noninvasive, non-native plants fall into a gray area in the context of "naturalness" for an area protected as Wilderness because they provide some positive ecological services even as they degrade wilderness character. Thus, wilderness managers face a difficult challenge in coping with the long-term impacts of visitor use on wilderness conditions and character.

Minnesota

A review and synthesis of recreation ecology research supporting carrying capacity and visitor use management decisionmaking

Resource and experiential impacts associated with visitation to wilderness and other similar backcountry settings have long been addressed by land managers under the context of “carrying capacity” decisionmaking. Determining a maximum level of allowable use, below which high-quality resource and experiential conditions would be sustained, was an early focus in the 1960s and 1970s. However, decades of recreation ecology research have shown that the severity and areal extent of visitor impact problems are influenced by an interrelated array of use-related, environmental, and managerial factors. This complexity, with similar findings from social science research, prompted scientists and managers to develop more comprehensive carrying capacity frameworks, including a new Visitor Use Management framework. These frameworks rely on a diverse array of management strategies and actions, often termed a “management toolbox,” for resolving visitor impact problems. This article reviews the most recent and relevant recreation ecology studies that have been applied in wildland settings to avoid or minimize resource impacts. The key findings and their management implications are highlighted to support the professional management of common trail, recreation site, and wildlife impact problems. These studies illustrate the need to select from a more diverse array of impact management strategies and actions based on an evaluation of problems to identify the most influential factors that can be manipulated.

Journal of Forestry

A review and synthesis of recreation ecology research findings on visitor impacts to wilderness and protected natural areas

The 50th anniversary of the US Wilderness Act of 1964 presents a worthy opportunity to review our collective knowledge on how recreation visitation affects wilderness and protected natural area resources. Studies of recreation impacts, examined within the recreation ecology field of study, have spanned 80 years and generated more than 1,200 citations. This article examines the recreation ecology literature most relevant to wilderness and backcountry, with a focus on visitor impacts to vegetation, soil, wildlife, and water resources. We also review relationships with influential factors, such as the amount of use, visitor behavior, and vegetation type. An understanding of these impacts and their relationships with influential factors is necessary for land managers seeking to identify acceptable limits of impact or selecting management actions that will effectively avoid or minimize resource impacts.

Journal of Forestry

Since “Groundwater and surface water–A single resource”: some U.S. Geological Survey advances in modeling groundwater/surface-water interactions

Field and interpretive studies conducted by T.C. Winter and U.S. Geological Survey colleagues, and summarized in the 1998 publication “Groundwater and Surface Water – A Single Resource”, inspired a new generation of research centered on extensions of the groundwater-flow code MODFLOW to more sophisticated simulation of coupled groundwater and surface-water systems. Guided by emerging concerns with water availability, safe yields from wells, health of aquatic habitat, and climate change, the changes to MODFLOW involve: 1) the ability to more precisely and accurately represent the interface between surface and subsurface flows and 2) the consideration of a variety of mechanisms that influence their interaction. A review of the most important changes to the code is supplemented in this article by selected case studies in an effort to show the scope of the advances. The updates discussed include the Streamflow Routing (SFR), Lake (LAK), and Unsaturated-Zone Flow (UZF) Packages in MODFLOW-2005 and the Groundwater Management (GWM), Local Grid Refinement (LGR), and Newton (NWT) formulation versions of MODFLOW-2005. New developments feature the integration of rainfall-runoff modeling with MODFLOW in GSFLOW, coupling of GFLOW and MODFLOW in a hybrid code, and the forthcoming unstructured grid version of MODFLOW. They promise continued advances in the ability to use science to protect the single water resource.

Acque Sotterranee: Italian Journal of Groundwater

Trout fishing in Michigan waters of Lake Superior, 1952

This article has been prepared to present the results of recently completed statistical studies on the fishery in the State of Michigan waters of the lake. The tabulations of production of lake trout and the estimates of levels of fishing pressure and abundance in the various statistical districts have been based on the monthly reports submitted by commercial operators to the Michigan Department of Conservation and turned over to the U.S. Fish and Wildlife Service for statistical analysis. To be sure, trends indicated by these statistics may not hold exactly for other areas of the lake. Conditions in Michigan are nonetheless of primary importance since during the last 25 years that state has accounted for nearly half of the entire Lake Superior trout production and for more than 70 percent of the take in U.S. waters.

The Fisherman

Trends of chlorinated organic contaminants in Great Lakes trout and walleye from 1970-1998

Levels of chlorinated organic contaminants in predator fish have been monitored annually in each of the Great Lakes since the 1970s. This article updates earlier reports with data from 1991 to 1998 for lake trout (Salvelinus namaycush) and (Lake Erie only) walleye (Sander vitreus) to provide a record that now extends nearly 30 years. Whole fish were analyzed for a number of industrial contaminants and pesticides, including polychlorinated biphenyls (PCBs), dichloro-diphenyl-trichloroethane (DDT), dieldrin, toxaphene, and mirex, and contaminant trends were quantified using multicompartment models. As in the past, fish from Lakes Michigan, Ontario, and Huron have the highest levels of PCBs, DDT, and dieldrin; Superior has the highest levels of toxaphene; and Ontario has the highest levels of mirex. In the period after curtailment of chemical use, concentrations rapidly decreased, represented by relatively short half-lives from approximately 1 to 9 years. Although trends depend on both the contaminant and the lake, in many cases the rate of decline has been decreasing, and concentrations are gradually approaching an irreducible concentration. For dioxin-like PCBs, levels have not been decreasing during the most recent 5-year period (1994 to 1998). In some cases, the year-to-year variation in contaminant levels is large, mainly because of food-web dynamics. Although this variation sometimes obscures long-term trends, the general pattern of a rapid decrease followed by slowing or leveling-off of the downward trend seems consistent across the Great Lakes, and future improvements of the magnitude seen in the 1970s and early 1980s likely will take much longer.

Archives of Environmental Contamination and Toxico

Mapping and converting essential Federal Geographic Data Committee (FGDC) metadata into MARC21 and Dublin Core: towards an alternative to the FGDC Clearinghouse

The purpose of this article is to raise and address a number of issues related to the conversion of Federal Geographic Data Committee metadata into MARC21 and Dublin Core. We present an analysis of 466 FGDC metadata records housed in the National Biological Information Infrastructure (NBII) node of the FGDC Clearinghouse, with special emphasis on the length of fields and the total length of records in this set. One of our contributions is a 34 element crosswalk, a proposal that takes into consideration the constraints of the MARC21 standard as implemented in OCLC's World Cat and the realities of user behavior.

D-Lib

Review of techniques to prevent introduction of zebra mussels (Dreissena polymorpha) during native mussel (Unionoidea) conservation activities

Because of the declines in diversity and abundance of native freshwater mussels (superfamily Unionoidea), and the potential decimation of populations of native mussels resulting from the rapid spread of the exotic zebra mussel Dreissena polymorpha, management options to eliminate or reduce the threat of the zebra mussel are needed. Relocating native mussels to refugia (artificial and natural) has been proposed to mitigate the threat of zebra mussels to native species. Relocation of native mussels to refugia such as fish hatchery facilities or natural habitats within their historic range. Which are unlikely to be infested by zebra mussels, necessitates that protocols be developed to prevent the inadvertent introduction of zebra mussels. Several recent studies have developed Such protocols, and have assessed their effectiveness on the health and survival of native mussels during subsequent relocation to various refugia. The purpose of this project is to synthesize and evaluate the current protocols and to develop a set of procedures that resource managers and researchers should consider before conducting conservation activities in zebra mussel infested waters. We found that the existing protocols have many common points of concern, such as facility modification and suitability, zebra mussel risk assessment and management procedures, and health and disease management procedures. These conservation protocols may have broad applicability to other situations and locations. A summary and evaluation of the information in these main areas, along with recommended guidelines, are presented in this article.

Journal of Shellfish Research

Satellite telemetry and wildlife studies in India: Advantages, options and challenges

Greater spatial coverage, accuracy and non-invasiveness of satellite technology make it one of the best tools to track long-distance migrants, which is otherwise difficult using conventional radio telemetry. In this article, we review the evolution of satellite telemetry and its application. We provide examples of three recent studies in India that have demonstrated and created a widespread appreciation of the use and benefits of satellite telemetry among biologists and managers. We also discuss the future prospects of this technology vis-a-vis benefits and challenges in the Indian subcontinent.

Current Science

What records have we been breaking?

"Today was another record-breaking day," the evening radio or television declares. High temperatures, low temperatures, floods, drought - take your choice. But how can we put these pronouncements in perspective? What do they really mean? We present two types of information in this article: 1) an analysis of daily air temperature and precipitation for Fort Collins and 2) an analysis of annual precipitation for Fort Collins. Each analysis provides a different meaning to the statement about a record-breaking day or year.

Colorado

Relationship between chemical structure and rat repellency

Repellent activity is defined as the activity of a compound in preventing consumption of, or gnawing attacks upon, foodstuffs or articles containing or treated with the candidate substance. Data are presented on repellency indices of 2700 compounds, and it is shown that repellency is associated with specific functional groups attached to alkyl, aryl, or heterocyclic nuclei. Functional groups containing nitrogen, sulfur or halogens are most active, with amines, imides, thiocyanates and thiocarbamates forming some of the most active classes. Activity of any functional group may be affected by molecular weight, unsaturation, or spatial configuration of the nucleus, or by the presence of additional substituent groups.

National Research Council, Chemical-Biological Coo

Interactions of wolves and dogs in Minnesota

This article reports on the nature and extent of wolf-dog interactions in Minnesota, based on investigations of complaints received by personnel of the federal government dealing with wolf-depredation control. Findings may indicate the wolf-dog interactions that can be expected in other recovery areas.

Wildlife Society Bulletin

Type specimens and basic principles of avian taxonomy

"Ornithology" may be defined as the scientific study of birds. No aspect of avian biology, including management and conservation, can be carried out without reference by name to birds at some taxonomic level. Thus, the names of species of birds, and of groups of species, can fairly be considered to be of primary importance in ornithology. To be useful, these names themselves must be defined and related to biological entities. The definition of a name is accomplished by the designation of a "type." The International Code of Zoological Nomenclature, in paragraph (C) of Article 72 (third edition, 1985), establishes criteria for eligibility of a name-bearing type. The type of a species or sub-species name is the biological specimen defined by the name, and later use of the name implies specific or subspecific identity with the type. It is imperative, therefore, that a type be available for study and comparison so that the identity of other material with it can be established.

The Auk

May the forethought (and studies) be with your campsite-protection planning!

Visitation has reached record levels along the Appalachian Trail, a 2000+ mile footpath extending from Maine to Georgia along the crest of the Appalachian Mountains. Camping impacts associated with this use have also expanded rapidly in recent years, particularly in popular National Parks and at attraction features such as lakes and ponds. This article reviews recreation ecology research on camping impacts and their relationship to amount of use and environmental attributes. Management options for responding to camping management problems are described, including the manipulation of use-related, environmental, and managerial factors.

Register

Questions about Thayer's Gull

In response to recently published articles about the taxonomic status of Thayer's Gull, Larus thayeri, we pose several questions that should be answered before a taxonomic decision can be made.

Ontario Birds

FrogwatchUSA

full text: Frogs and toads are perhaps the most approachable and available of all our wildlife. In many, if not most places, they are abundant. In wetter parts of the East, almost anyone outside on a warm rainy night in spring will hear their dream-like calls, bellows, trills and snores. Even in the deserts of the Southwest, a nocturnal trip after a summer monsoon will yield toads moving across the roads toward a cacophonous orgy of mating and calling in the roadside ditches and desert pools. Birds share with frogs and toads this same sense of presence in our daily lives. But the difference is that birds are like the attractive neighbor who just never gives you the time of day, while frogs are more like the troglodyte who appears regularly to chat, philosophize, and have a beer. Uninvited, frogs appear in our water gardens, toads are on our stoops in the morning, we catch them when we are kids, raise their babies in the aquarium, and feel sorry when we find we have run them over with the lawnmower. When concerns about declining populations of amphibians reached the mass media, the Secretaries' office became involved. In addition to using traditional research mechanisms to investigate the problem, the Secretary also wanted to involve the public directly. The combination of high public appeal and the relative ease with which frog calls can be learned made a large-scale monitoring program for frogs and toads possible. What emerged was a program called Frogwatch USA, modeled after a successful Canadian program with a similar name. A web site was created (www.frogwatch.org) that presented potential frogwatchers with directions and a way to register their site online as well as enter their data. Observers chose where to count frogs depending on what they felt was important. For some it was their backyard, others chose vulnerable wetlands in their neighborhoods, or spots on local refuges and parks. Initially funded at $8,000 a year and then after two years increased to $25,000, most of the first part of this program's life was spent developing the tools and web site to document counts of frogs online. Despite the lack of time available to promote the program, send out press releases and recruit observers, news of the program quickly spread by word of mouth and the electronic media. Many newspaper articles later, we found a large number of people had become involved with counting frogs in their neighborhoods and backyards. Current figures show 1,456 observers who have registered at 1,683 sites logging almost 5,000 visits. These visits yield information on when and what species are calling from wetlands throughout the United States. These records are usually the only records of information about frogs and toads for those sites and become a permanent record that can be revisited in future years. Additionally, when observers make a lot of visits or there are many sites in a region, a phenology of calls can be created that documents when it is most likely in that year for each species to be recorded. Finally, even for those observers whose data we may mistrust and therefore are likely to eliminate from analyses, these people have taken the time to leave their televisions, go outside, and directly experience frogs, toads, and all that occur in Nature. In 1999 it was decided that FrogwatchUSA needed to work with another group that specifically focused on environmental education and outreach. After talking to a number of organizations we found that the National Wildlife Federation, with their Backyard Wildlife Habitat, Endangered Species, and other programs along with their four million members who are interested in nature, would be an excellent match. Thus a partnership was born. After over a year of work between Interior and National Wildlife Federation biologists and lawyers, an agreement has been created that places the Federation as the lead of Frogwatch USA. It will now take care of res

People, Land, and Water

Trekking poles: Can you save your knees and the environment?

The increasing use of trekking poles has stimulated a growing awareness of some environmental and social impacts associated with their use. These impacts have not been documented in the scientific literature. This article reviews the impacts of trekking pole use to provide a basis for further dialogue, and suggests how they may be altered or used in ways that will minimize impact.

Register

Schizochromism in a Peregrine Falcon from Arizona

Herein, we report the first record of schizochromism in the Peregrine Falcon (Falco peregrinus). Our example is a nestling from southern Arizona. The lack of dark brown pigment in this bird made it closely resemble the blue-gray plumage of an adult. Near fledging time, the bird was eaten by its nestmates, so this article also documents cannibalism.

Journal of Raptor Research