Volume No. 11, 2002
The goals of aquatic Gap Analysis are to map the biodiversity and habitats of aquatic species and to determine the gaps in the representation of these species and habitats within protected areas. Aquatic Gap Analysis is a relatively new component of the U.S. Geological Survey’s (USGS) National Gap Analysis Program (GAP). Aquatic GAP pilot projects in Missouri, Ohio, and South Dakota are either well under way or nearing completion. In 2001, the USGS, in cooperation with several state resource-management agencies, began a regional Aquatic GAP project in the Great Lakes Basin (GL Aquatic GAP).
There are several reasons why an aquatic Gap Analysis is being undertaken in the Great Lakes Basin. This basin is a 196,520 square-mile, geographically distinct, and biologically rich region of the United States (U.S.) and Canada. It contains over 11,000 miles of coastline, a large concentration of wetlands, diverse forests, and hundreds of tributary streams of various sizes (U.S. Environmental Protection Agency and Government of Canada 1995; Figure 1). In the U.S., the drainage area includes parts of Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin.
Figure 1. The Great Lakes Basin in the United States and Canada. The shaded area represents the Great Lakes Basin.
The Great Lakes Basin is globally important because it contains approximately 18% of the Earth’s fresh surface water (U.S. Environmental Protection Agency and Government of Canada 1995) and supports more than 30 communities of plants and animals found nowhere else (The Nature Conservancy 1997). The rivers, streams, wetlands, and coastal habitats of the Great Lakes Basin contain over 300 species of fish and are of major economic and ecological importance because critical life-history stages of many fish and other species depend on them (Greeley 1940, Jude and Pappas 1992, Whillans 1990). In 1996, 2 million anglers fished the Great Lakes and added more than $1 billion to the regional economy (Michigan Sea Grant 2000). The commercial fish harvest in the basin was 63 million pounds in 1996, bringing in more than $43 million (Michigan Sea Grant 2000). Although abundant data on assemblages of fishes and aquatic macroinvertebrates are available for the region, knowledge of the aquatic biodiversity is incomplete.
Despite the value of the aquatic resource, anthropogenic influences have reduced the availability of aquatic habitat and access to historical fish-spawning grounds and nurseries in the tributary streams, wetlands, and coastal margins of the Great Lakes. Preservation of biological diversity is a regional priority because of its strong connection to the economy and health of the surrounding human population and wildlife resources through tourism, recreation, fisheries, and water use for human needs and ecosystem function (Governments of Canada and the United States 2002, U.S. Environmental Protection Agency 2002, U.S. Policy Committee 2001).
The goal of GL Aquatic GAP is to map the species distributions and diversity of fish and other aquatic species and their habitats and to identify gaps in the conservation of these species and associated habitats within the eight states in the Great Lakes Region. The seven project objectives are listed below.
Delineate and map ecologically similar drainage areas of the Great Lakes.
Classify aquatic habitats in rivers, streams, and in selected coastal margins and wetlands using regionally consistent methods.
Develop aquatic biological databases at state and regional scales.
Map the known and predicted occurrence and distribution of fish and other aquatic species in streams and selected coastal and wetland habitats.
Complete a gap analysis of fish and selected aquatic invertebrate species.
Serve these data and products on the Internet and on CD-ROM.
Analyze, synthesize, interpret, and publish results at statewide, lakewide, and basinwide scales.
The study team consists of biologists, hydrologists, and geographers from the USGS and several state agencies in Michigan, New York, Ohio, and Wisconsin. Due to the size of the Great Lakes Region, studies must be performed in stages, with future studies planned to start in other Great Lakes states when current studies are near completion. Studies that began in 2001 in Michigan, New York, and Wisconsin are planned for completion in 2006. The Ohio pilot study began in 2000 and is planned for completion in 2005 (see separate status report on Ohio in the State Project Reports section).
Each state-level gap analysis consists of work in three habitat types: streams and rivers, coastal margins, and wetlands. The latter two components are being investigated as pilot studies in 2001-06. Gap analyses of the open waters of the Great Lakes and inland lakes are not currently part of GL Aquatic GAP.
State-level and pilot studies begin with a low-intensity planning year that is followed by four years of intensive database development, analysis, animal-modeling activities, and gap analysis. Major products and publications are completed in the final (fifth) year. Active partners to date include the Michigan Department of Natural Resources (MDNR), New York State Department of Environmental Conservation (DEC), Ohio Lake Erie Commission, Ohio Environmental Protection Agency, Ohio Department of Natural Resources, U.S. Fish and Wildlife Service, and Wisconsin Department of Natural Resources.
Regional requirements for consistent and integrated information are being developed to allow synthesis of findings at statewide, lakewide, and basinwide scales. Many of the methods used in the pilot studies in Missouri and Ohio are used in GL Aquatic GAP. One of these methods uses Valley Segment Types (VSTs), a classification system based on channel characteristics, riparian zone features, total catchment area, other hydrogeomorphic features, and temperature (Missouri Resource Assessment Partnership 2000, Lammert et al. 1997). VST classification forms the basis for species modeling when coupled with data on known species occurrence and distribution.
The approach under development for the classification of coastal habitats, as for streams, is based primarily on physical features. For example, wetlands in the Ohio portion of the Lake Erie Basin are classified based on hydrology and vegetation, in cooperation with Ohio’s terrestrial GAP study.
A centralized biological database is being developed in Oracle™ using data collected by government agencies or academic institutions and quality-assured by the USGS.1 The centralized database will contain and serve aquatic species occurrence and abundance data at the basinwide scale. The ITIS (Integrated Taxonomic Information System) codification and naming system for fish species is used for standardization across the basin. The centralized database will serve GL Aquatic GAP biological data to the National Biological Information Infrastructure.
1 The use of trade names is for identification purposes and does not constitute an endorsement by the USGS.
In preparation for gap analysis, the occurrence and distribution of aquatic species will be predicted for all stream segments and for selected wetland and coastal areas in the region. Predictive models of species occurrence in streams will incorporate existing species occurrence data and aquatic habitat characteristics (VSTs). Habitat models vary from simple extrapolation models to sophisticated multivariate models. The Genetic Algorithm for Rule-set Production (GARP; Stockwell and Peterson 1999), desktop version (Scachetti-Pereira 2002), is a statistical modeling approach being used for Ohio streams.
Progress and Preliminary Findings
In 2001, data acquisition was a priority in the Michigan, New York, and Wisconsin GAP studies. Map layers acquired include land cover (1994); surficial and bedrock geology; elevation (30-meter National Elevation Data); hydrography (National Hydrography Dataset [NHD], 1:100,000 scale); and ecoregions. In 2003, the VST classification will be developed from these layers. The original VST classification completed by the MDNR-Institute for Fisheries Research (IFR) in 1999 (Zorn et al. 2002) was recently updated to replace the RF3 river-reach file with the 1:100,000 NHD.
The centralized database under development will eventually contain data on aquatic species from well over 175,000 sampling sites in Michigan, New York, Ohio, and Wisconsin. Data from approximately 25% of these sites were collected from 1980 to 2001. Data from Michigan are available for 145 fish species collected from approximately 8,620 sampling sites. Data from New York are available for 179 fish species collected from approximately 135,400 sampling sites. Data from Ohio are available for 160 fish species collected from approximately 5,500 sites, 8 species of freshwater mussels collected from approximately 2,900 sites, and 20 species of crayfish and 2 species of freshwater shrimp collected from approximately 5,000 sites. Data from Wisconsin are available for 130 fish species collected from approximately 22,000 sites.
In 2002, coastal shoreline and bathymetric data for Lakes Erie and Ontario were acquired from the National Oceanic and Atmospheric Administration and from the U.S. Army Corps of Engineers. Potential pilot-study areas are being investigated; one in Lake Ontario and two each in Lakes Erie and Huron. From these candidate areas, three will be selected for a coastal gap analysis based on the amount of available data. Much of the available fish-occurrence data for nearshore areas of eastern Lake Ontario, a potential pilot-study area, have been obtained from the New York DEC and USGS.
In Ohio, biological database development and VST classification were completed in 2000 and 2001. The occurrence and distribution of 150 fish species were mapped, modeled, and compared in 2002 using simple extrapolation methods and GARP methods. Species modeling of Ohio crayfish and freshwater mussels are planned for 2003. In 2004, gap analysis will be undertaken in Ohio and will include an evaluation of diversity patterns of aquatic species in relation to human and natural factors as well as a comparison of the degree to which aquatic species are represented in protected areas versus unprotected areas.
A Web site was established in August 2002 at the URL http://www.glsc.usgs.gov/GLGAP.htm. A USGS Fact Sheet on GL Aquatic GAP is planned for publication in 2003. A journal publication and a final report on gap analysis of fish, freshwater mussels, and crayfish in Ohio are planned for 2004 and 2005, respectively.
In October 2002, investigators from GL Aquatic GAP and the Missouri Resource Assessment Partnership met to discuss common methods and approaches to aquatic gap analysis. Semiannual meetings with state and local stakeholders and frequent presentations at scientific meetings and at Great Lakes regional workshops are important for communication of progress and to obtain feedback on the project.
In cooperation with The Nature Conservancy and the International Joint Commission, a daylong session entitled “Biodiversity Conservation in the Great Lakes Region” is planned at the 46th annual meeting of the International Association for Great Lakes Research (IAGLR) in Chicago, Illinois, from June 22 to 26, 2003. Presentations from the GAP Operations office; New York and Upper Midwest terrestrial GAP projects; the GL Aquatic GAP project; and from several U.S. federal and Canadian provincial agencies and nongovernmental organizations are planned.
For more information on GL Aquatic GAP, contact Donna Myers, Coordinator, U.S. Geological Survey, Columbus, Ohio, at dnmyers@usgs.gov or (614) 430-7715.
Governments of Canada and the United States. 2002. Lake Erie Lakewide Management Plan 2002. Section 4, A habitat strategy for Lake Erie. Burlington, Ontario. pp. 17-24.
Greeley, J.R. 1940. Fishes of the watershed with annotated list. A biological survey of the Lake Ontario watershed. Section II: 41-81.
Jude, D.J., and J. Pappas. 1992. Fish utilization of Great Lakes coastal wetlands. Journal of Great Lakes Research 18:651-672.
Lammert, M., J. Higgins, D. Grossman, and M. Bryer. 1997. A classification framework for freshwater communities: Proceedings of The Nature Conservancy’s Aquatic Community Classification Workshop; New Haven, Missouri, April 9-11, 1996. The Nature Conservancy, Arlington, Virginia.
Michigan Sea Grant. 2000. The Great Lakes Basin statistics. Michigan Sea Grant Fact Sheet MICHU-SG-00-406.
Missouri Resource Assessment Partnership. 2000. Aquatic GAP pilot project. Accessed January 13, 2003 at URL http://www.cerc.usgs.gov/morap/projects.asp?project_id=1.
Scachetti-Pereira, R. 2002. DesktopGarp. Accessed December 16, 2002, at URL http://beta.lifemapper.org/desktopgarp/.
Stockwell, D., and D. Peterson. 1999. The GARP modeling system: Problems and solutions to automated spatial prediction. International Journal for Geographical Information Science 13:143-158.
The Nature Conservancy. 1997. Great Lakes in the balance―protecting our ecosystem’s rich natural legacy. The Nature Conservancy, Chicago, Illinois. 25 pp.
U.S. Environmental Protection Agency and Government of Canada. 1995. The Great Lakes―An environmental atlas and resource book. Third edition. Toronto, Ontario and Chicago, Illinois. 44 pp.
U.S. Environmental Protection Agency. 2002. Lake Michigan Lakewide Management Plan 2002. Chicago, Illinois. Pp. 26-40.
U.S. Policy Committee. 2001. Great Lakes Strategy 2002: A plan for the new millennium. U.S. Environmental Protection Agency, Chicago, Illinois, 37 pp.
Whillans T.H. 1990. Assessing threats to fishery values of Great Lakes wetlands. Pages 156-164 in J. Kusler and R. Smardon, editors. Proceedings of an International Symposium on Wetlands of the Great Lakes, Protection and Restoration Policies; Status of the Science. Niagara Falls, New York, May 16-18, 1989.
Zorn, T.G., P.W. Seelbach, and M.J. Wiley. 2002. Distributions of stream fishes and their relationship to stream size and hydrology in Michigan’s Lower Peninsula. Transactions of the American Fisheries Society 131:70-85.
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