Arthropods of Canadian Grasslands Prospectus

Prepared in 2002 on behalf of the Biological Survey by:

Joseph D. Shorthouse, Department of Biology, Laurentian University, Sudbury, Ontario
and
Terry A. Wheeler, Department of Natural Resource Sciences, McGill University, Macdonald Campus, Ste-Anne-de-Bellevue, Quebec, H9X 3V9

pdf version

Executive Summary

Résumé

The Biological Survey of Canada (Terrestrial Arthropods) and the Grasslands Project

Overview of Canadian Grasslands

Scope of the Project

Objectives of the Grasslands Project

Existing Information

Rationale for a Synthesis on Grassland Arthropods

Biodiversity and Ecology of Grassland Arthropods

Conservation and Restoration of Grassland Ecosystems

Measuring and Monitoring the Effects of Human Activities and Climate Change

Core Procedures

Expected Results and Products

Core Knowledge and Infrastructure

Core Scientific Products

Selected Applications

Funding and Support

References

Appendix I. Classification and Distribution of Canadian Grasslands

Selected Grassland References

Executive Summary

Résumé

Les prairies sont un des principaux biomes canadien. La plus grande étendue de cet habitat couvre la portion sud des provinces des prairies canadiennes. Des habitats similaires se retrouvent aussi du Yukon jusqu’à l’est de l ’Ontario. Les prairies du Canada ont été durement exploitées pour l’agriculture et la survie de ces écosystèmes est maintenant menacée. Malgré l’utilisation intensive de cet habitat par les humains, nos connaissances sur la biodiversité, l’écologie et les impacts sur les communautés vivantes reliés au changement dans ces prairies sont très limités. Ce manque de connaissances est d’autant plus important chez les insectes et autres arthropodes, qui sont les groupes les plus diversifiés, abondants et écologiquement importants dans les prairies. Le projet sur les arthropodes des prairies canadiennes de la Commission biologique du Canada est un effort nationale majeur pour répondre à ce manque de connaissances.

Les objectifs à long terme de ce projet sont de répondre à trois questions majeures:

• Quelle est la biodiversité des arthropodes associées aux prairies canadiennes?
• Quelles sont les interactions écologiques entre les arthropodes et les autres groupes d ’espèces présents dans les prairies canadiennes?
• Quel est l ’impact des activités humaines et du changement climatique sur les arthropodes des prairies et, inversement, quels sont les impacts des arthropodes des prairies sur les activités humaines?

Pour répondre à ces questions, la participation de plusieurs collaborateurs conduisant des études systématiques et écologiques dans les prairies canadiennes sera indispensable. L’échantillonnage et le travail sur le terrain dans une variété d’habitats de prairies faciliteront les études taxonomiques des arthropodes associés à ces habitats. La recherche en systématique est essentielle pour fournir les informations de base qui pourront par la suite être combinées à des études sur l’écologie ou autres études appliquées. Des programmes d’échantillonnages standardisés dans des habitats sélectionnés fourniront des données quantitatives sur les populations des arthropodes. Ces données serviront à l’analyse des similarités et différences parmi les communautés d’arthropodes provenant de différentes regions et de differents types de prairies. Étant donné leurs implications dans le développement de l’agriculture dans l’ouest canadien, les prairies fournissent un excellent système pour étudier les impacts des activités humaines sur un écosystème relativement simple. De plus,elles perme ent d’étudier les effets potentiels à long terme de facteurs comme le changement climatique.

Les produits et applications de ce projet seront diversifiés. La recherche sur la diversité et l ’écologie des arthropodes fournira une source à long terme de spécimens et de données qui pourront servir pour de futures projets sur la biologie des arthropodes des prairies.Les publications sur la biodiversité des arthropodes des prairies,sur l ’écologie des arthropodes d ’habitats sélectionnés et sur les interactions entre les activités humaines et les arthropodes fourniront des moyens visibles de disséminer les connaissances acquises lors de ce projet. Lorsque ces connaissances sur la systématique et l ’écologie des arthropodes des prairies seront en place,il y aura plusieurs opportunités pour de futures utilisations de ces données pour des études appliquées comme la conservation d’habitats, le contrôle des effets de l’agriculture, des feux, du changement climatique et autres changements sur l ’habitat.

Avec la conscience grandissante du publique sur la crise de biodiversité, la communauté scientifique est hautement sollicitée pour comprendre et préserver les écosystèmes. Au même moment, les obligations internationales du Canada demandent que la flore et la faune de nos frontières soient cataloguées, contrôlées et protégées.Il y a donc un besoin urgent de connaître la biodiversité des arthropodes des prairies, qui ont, pour la majorité, un rôle encore inconnu dans ces importants écosystèmes. La Commission biologique du Canada est l ’organisme le mieux placé pour coordonner ce grand projet.

The Biological Survey of Canada (Terrestrial Arthropods) and the Grasslands Project

The Biological Survey of Canada (Terrestrial Arthropods) was established in 1977 by the Entomological Society of Canada to help characterize the insect fauna of Canada and coordinate national initiatives in taxonomic, faunistic and ecological entomology. The impetus for this agency was the concern that less than half the estimated 67,000 species of insects, spiders, mites and their relatives found in Canada have even been described; the ecological roles are known for an even smaller percentage. Since 1980,the Survey has been associated with the Canadian Museum of Nature. Initiatives of the Survey are coordinated by a Scientific Committee, comprised of 18-20 entomologists from across Canada, working in conjunction with the Survey Secretariat (headed by Dr. H.V. Danks). Over 20 books have been produced by the Survey including Arctic Arthropods, Insects of Peatlands and Marshes in Canada, Canada and its Insect Fauna, and most recently (1997), the 1034-page volume Insects of the Yukon.

The Arthropods of Canadian Grasslands Project will be the largest and most ambitious undertaken by the Survey. The project will involve numerous collaborating researchers and will generate products in a variety of formats. We envisage major volumes on the biodiversity of grassland arthropods, and on the ecological relationships of arthropods in selected grassland habitats, both pristine and human-modified. Electronic databases will allow new faunistic and ecological data to be incorporated from ongoing studies of the fauna. A Project web site (www.biology.ualberta.ca/bsc/english/grasslands.htm) and publication of an annual Grasslands Newsletter help coordinate researchers and their projects.

Overview of Canadian Grasslands
Grasslands are communities characterized by mixed herbaceous vegetation dominated by perennial grasses or grass-like plants. In natural grasslands of pristine (climax) condition, grasses and sedges are perennial; annual grasses are present where the perennial cover has been disturbed. Grasslands are often classified according to the relative height of the canopy. Consequently, terms like ‘short grass’, ‘mixed grass’ and ‘tall grass’ are applied to describe the relative heights of plants in the vegetation layers in a particular location. Perennial grasslands are also classified as natural, semi-natural or artificial. Artificial grasslands are those that have been established by the seeding of annual, exotic species such as wheat, barley and corn. They are usually in land in which the native species have been controlled or eliminated by tillage. Grazed artificial and natural grasslands are referred to as pasture and rangeland, respectively.

Trees are generally not associated with prairie grasslands because of unsuitable growing conditions and those present are usually stressed. However, stands of trees are found in various regions of the prairies where they owe their existence to sufficient groundwater supply, effects of elevation, or protection from fire. For example, forests in the Cypress Hills of Alberta and Saskatchewan owe their presence to the effects of topographic relief, while tall grass prairies and savannas in Manitoba and Ontario have a tree cover that results from sufficient groundwater. A distinctive feature of some prairies and the aspen parkland, is the riverine forests of broadleaf deciduous tree species such as Populus deltoides (cottonwood), Acer negundo (Manitoba maple) Salix interior (sandbar willow) and Salix amygdaloides (peach-leaved willow). These trees dominate the river margins, floodplains and upper-bank sandbars.

The prairie biome of Canada is found in southern Alberta, Saskatchewan and Manitoba and comprises one of the country’s five major biomes. Prairie grasslands cover about 5% of Canada’s land area and are associated with an extreme continental climate. Winters are normally cold and summers hot, annual temperature range is large, and a negative moisture index with summer moisture stress is typical. Our prairie grasslands are found in an arc that stretches to the east of the Rocky Mountains in Alberta, north to near Edmonton then southeast towards the Manitoba-Ontario border (Figs. 1, 2). They are bounded to the west and north by aspen parkland and continue in the south across the border with the United States. Less extensive and discontinuous prairie-type grasslands also occur in British Columbia (Fig. 3), northwestern Alberta, the Yukon Territory, and the Great Lakes region of Ontario. The dominant types of grasslands in this biome are described in Appendix 1.

Fig. 1

Fig. 2

Fig

Scope of the Project
Plant communities that may be defined as grasslands occur throughout Canada from coast to coast and from the arctic to southern Ontario. Given the wide range of species diversity, ecological relationships and environmental conditions present across these communities it has been necessary to limit the scope of this project. Consequently, the Grasslands Project will focus on the grasslands of the prairie ecozone as well as outlying grasslands in the west and east that have significant overlap in plant and animal species and climatic conditions. The extensive arctic grasslands dominated by grasses and sedges are not included, nor are the wetland, estuarine and coastal grasslands of eastern Canada.

There is an integral ecological connection between grassland ecosystems and the aquatic systems that are associated with them. For this reason, studies of selected aquatic ecosystems will be included in the project. Prairie sloughs, potholes and associated wetlands are a major source and sink of water for grassland communities, and provide habitat for species that either inhabit terrestrial grasslands for part of their life cycle, or have close interactions with terrestrial species. Because of the importance of riverine forests in defining the overall species diversity in grasslands, the riparian fauna of rivers in the Canadian prairies will also be considered.

Objectives of the Grasslands Project
The project will address three general questions on the nature of arthropods associated with Canadian grasslands:

• What is the biodiversity of arthropods associated with Canadian grasslands? How diverse are these communities, how similar are they among grassland types, and how different are they from arthropod communities in other habitats?

• What are the ecological interactions between arthropods, plants and other animal species in Canadian grasslands? What are the significant species assemblages in selected habitats and what are their ecological roles?

• What are the impacts of human activity and global climate change on grassland arthropod communities; conversely, what are the impacts of grassland arthropods on human activities?

These questions define the long-term objectives of the Grasslands Project. These objectives will, in turn, be achieved by addressing short-term objectives defined in this document.

Existing Information
The grassland biome has persisted in North America since the Miocene (Matthews 1979) and despite major changes in their geographic distribution and extent, grasslands remained distinct throughout the Pleistocene glaciations (Ritchie 1975, Matthews 1979). Holocene expansion of grasslands during the Hypsithermal warming interval may explain the presence of grassland outliers in regions beyond the southern prairie provinces (Moss 1952, Anderson et al. 1989). Most arthropod communities associated with native grasslands in Canada probably colonized their present habitats coincident with postglacial distributional changes in grasslands (Lehmkuhl 1980), although some species may have survived glaciation in refugial grasslands, such as those apparently present in Beringia (Matthews 1982). Following postglacial establishment of grassland communities, there were probably only minor changes to the ecosystems as a result of factors such as fire or grazing by large herbivores (Knapp et al. 1999). However, most grasslands in Canada were profoundly changed by European settlers (Turnbull 1979).

Given the longstanding importance of grasslands to Canadian agriculture, and the recent realization of their importance in biodiversity and conservation, it is not surprising that there is a body of existing research on the arthropods of Canadian grasslands. The Grasslands Project will build on this foundation.

Many entomologists affiliated with Agriculture Canada Research Stations, other government agencies or universities have undertaken studies of arthropods in Canadian grasslands. Reference collections have been assembled at many of these institutions as well as at the Canadian National Collection in Ottawa, and serve as important resources for researchers associated with this project. In addition to the data contained in collections, studies by individual researchers and some larger scale syntheses have resulted in a number of publications on the arthropods of Canadian grasslands.

The species diversity and faunistics of some grassland arthropod taxa have been more intensively studied than others. For example, the leafhoppers (Hemiptera: Auchenorrhyncha) have been the subject of numerous studies across the range of grassland types (e.g., Hamilton 1994, 1995, 1997, Whitcomb et al 1994) and other Hemiptera are also well characterized (e.g., Scudder 1993). There is also relatively complete information on the grasshoppers (Orthoptera) (e.g., Brooks 1858). In contrast, faunistic studies of grassland Diptera have been limited to only a few families (e.g, Boucher and Wheeler 2001).

Multi-taxon inventories using standardized sampling methods have produced species lists and analyses of selected taxa in localities such as the Okanagan Valley, British Columbia (Blades and Maier 1996) and Canadian Forces Base Suffield in southern Alberta (Finnamore 1998, Finnamore and Buckle 1999).

Directed ecological studies have examined the effects of fire and other factors on grassland arthropod communities. Roughley (2001) studied post-fire colonization of tall grass prairie in Manitoba and White (2001) examined the effects of fire on arthropods in palouse grasslands. Evans (1988) studied the effect of fire and other habitat changes on grasshopper populations in tall grass prairies.

However, except for pest species, we still know surprisingly little about the arthropod fauna of Canada’s grasslands. We do not know how many undescribed or unrecorded species are still to be found in the remaining pristine grasslands, nor do we know which species are threatened by human activities. As well, little is known about the ecological role of arthropods that have survived and adapted to lands converted to agriculture. The accumulation of available information on the diversity of grassland arthropods, as well as other taxa, is necessary to permit analyses of large-scale historical patterns and changes in the fauna.

Rationale for a Synthesis on Grassland Arthropods
The gaps in our knowledge of grassland arthropod communities make it clear that we must learn more about this fauna. Given the diversity of the arthropod communities involved, and the range and diversity of grassland ecosystems themselves, it is also clear that a large synthetic project developed by the Survey will be more informative than piecemeal investigations. This project will characterize grassland arthropods from multiple scientific perspectives, with a range of studies by different cooperators that focus on the species diversity, distribution and ecological roles of grassland arthropods, their role in the functioning of changing ecosystems, and the nature of their increasingly strong interactions with human activities. The great diversity of arthropods makes them ideal organisms for characterizing, understanding and monitoring the effects of short-term and long-term changes in the ecosystem, mainly because different arthropod species will respond at different scales to habitat characteristics and changes.

Biodiversity and Ecology of Grassland Arthropods
Grassland habitats are home to a large assemblage of arthropod species not found in other habitats. Consequently, these habitats are of great interest to systematists and evolutionary biologists. Many grassland arthropods are widespread in a range of grassland types and regions. Because of this it is necessary to study them in as wide as possible a range of sites and habitats. In contrast, many species, especially those associated with particular plant species or substrate types, are restricted in their distribution. Sampling is necessary to establish the true range of these species, as well as the vulnerability of those whose range is particularly restricted.

Grasslands are of great interest from a biogeographic point of view. This biome was persistent in North America during Pleistocene glaciations and many grassland species have an uninterrupted history of survival in this habitat through the Quaternary. Grasslands may have been persistent in glacial refugia such as Beringia during the Pleistocene as well; this has implications not just for the survival of isolated populations of arthropods there, but for the dispersal of Palearctic species into North America. At the other end of the scale, many of our current grassland habitats, especially at the eastern and western limits of their range, exist as isolated pockets. Studying the distribution of arthropods associated with these disjunct grasslands may help us to understand the history of these sites.

Grassland habitats provide a number of advantages to the study of arthropod ecology. Grasslands tend to have simpler trophic webs than forests or aquatic systems. Consequently, studies of species interactions or the effects of abiotic factors on species ecology and distribution are facilitated. Grasslands have a more two-dimensional structure than forests or lakes, which allows observation and measurements across a greater range of the habitat.

Because grassland habitats have characteristic dominant plant species that vary from site to site, it is relatively easy to establish relationships between particular plant species or communities and their associated arthropod assemblages. This permits detailed studies of plant-pollinator or plant-herbivore associations, and interactions within the assemblage of arthropods associated with particular plants or communities.

Conservation and Restoration of Grassland Ecosystems
Changes in our grasslands have produced some of the most productive agricultural lands in the world; however, it is recognized in many circles that far too much of our native grassland has been destroyed. The tall grass prairie of Manitoba, in particular, has provided highly productive agricultural lands, but this has come at a high price: the almost total demise of this community type. Of the original 6,000 km² of tall grass prairie in the Red River basin, only about 4 km² remains in scattered remnants like the Living Prairie Museum in Winnipeg, the Department of National Defense’s St. Charles Rifle Range in Winnipeg and the Tallgrass Prairie Preserve at Gardenton-Tolstoy. Prairie restoration projects are underway in areas like Beaudry Provincial Park near Winnipeg where the Manitoba Parks Branch is attempting to rehabilitate the area and restore the original tall grass cover.

Oak and pine savannas once covered 1,200 km² on sand plains in southwestern Ontario. Most of this ecosystem has been destroyed with only a few remaining tracts in southwestern Ontario. Similarly, alvar grasslands in the Great Lakes region have been reduced to a few small remnants and The Nature Conservancy considers most alvar types globally imperiled as a result of livestock grazing, limestone quarrying and urbanization.

The same pattern of human settlement and ecosystem alteration for food production has occurred on most of the palouse grasslands in British Columbia. Factors such as fire suppression, urban sprawl, orchards, vineyards, introduced species and cattle grazing have reduced the palouse grasslands in the Okanagan Valley to a few small vulnerable pockets.

The continued existence of the remaining tracts and remnants of Canada’s grasslands has become more important as efforts intensify to conserve ecosystems and the species they contain. Coupled with the need for increased research on prairie ecosystems is a greater urgency for an updated synthesis of information on the ecology of grasslands. As with all terrestrial ecosystems, arthropods play a fundamental role in the functioning and productivity of grassland ecosystems and this is why defining these roles will be a major objective of this project.

Measuring and Monitoring the Effects of Human Activities and Climate Change
Over the past 100 years, the biodiversity of Canada’s grasslands has been greatly reduced and altered as a result of agriculture. Much of the native grassland has been fragmented or eliminated, with corresponding decreases in native animal and plant life. Indeed, the grasslands of Canada’s prairies, and their arthropod inhabitants, are drastically different today than at the time of the first European settlement in the late 19th century. In the early years, as settlement expanded westward, effects on arthropod communities were not extensive because refuges for native species were left along fence lines, road allowances and in two sections of land (‘school lands’) left in a wild state in each township. Sloughs were left undrained and large tracts of aspen parkland to the north remained intact. This has changed dramatically over the past 50 years, as large scale harvesting machinery required unobstructed fields of a single crop. As a result, fence lines, road and railway allowances and school lands have declined, and remaining road and rail margins are sprayed with herbicides. Most aspen stands have disappeared. Rivers have been dammed to create irrigation reservoirs, and about 70% of the prairie wetlands and sloughs have been drained to provide additional agricultural lands, with obvious negative implications for aquatic life.

Settlers plowed under the original flora of the prairies and replaced this endemic flora with introduced crops of Eurasian steppe origin, many of which were grasses closely related to the native species. As a result, native insects were able to switch with ease from wild grasses to cereal crops. For example, the native wheat stem sawfly moved from native grasses to wheat, as did many species of grasshoppers, wireworms, cutworms and armyworms.

Such a small proportion of the original grasslands remain that that we will never know whether or not the assemblages they support today resemble those present prior to European settlement. However, there is little doubt that the native arthropod fauna on the whole has been diminished. The insect fauna of cultivated fields is depauperate with major taxa such as spiders, ants and Hemiptera rare or nonexistent. Grazing by cattle has also selectively altered the relative abundance of many prairie plants, and with them populations of associated insects. Few species of insects have likely become extinct because of settlement, but many have been reduced to small populations inhabiting scattered refuges. One of the objectives of this project is to help locate, study and hopefully preserve many of these refuges.

Because of the relatively recent settlement history in Canadian grasslands, we have data on the temporal and spatial scale of these habitat changes. This facilitates study the effects of known, long-term changes on a native habitat. The persistence of isolated patches of native prairie communities also provides the opportunity to study species survival and interactions in ecological islands of varying sizes and degrees of disturbance. Finally our altered grasslands provide an excellent opportunity for the study of interactions between introduced, mostly European species and native species.

Another type of change that may affect grasslands more than many other habitats is global climate change. Because of the already harsh continental climate and moisture limitation of grasslands, any exacerbation of these conditions will place additional selection pressures on these ecosystems. Arthropods would be among the first organisms to respond to these additional stresses and, as such, would serve both as indicators of habitat change and study organisms for the ability of ecosystems to respond to changes.

Core Procedures
The long-term accumulation of data on grassland arthropods requires careful planning and use of appropriate techniques for sampling and follow-up (Marshall et al. 1994, Danks 1996, Danks and Winchester 2000). This becomes especially important when one considers the diversity of arthropods, the complexity of habitats, and the importance of being able to compare the fauna of different regions. Although some projects, especially in systematics, can be undertaken by targeted collecting over a variety of grassland habitats, standardized sampling programs will be needed to provide specimens for use in ecological investigations. Controlled sampling techniques assess species diversity, abundance, seasonality, etc., in ways that allow valid comparison among sites (Marshall et al. 1994, Danks and Winchester 2000). For example, long-term studies on the effects of climate change, post-fire recovery or grassland restoration will only be meaningful when the collection of data follows a well designed procedure. In this way, the studies acquire predictive power. Consideration has already been given to sampling protocols in grasslands (Marshall et al 1994, Finnamore 1996, Finnamore et al 1998) and attention to study design between collaborators prior to sampling is strongly encouraged.

Studies on systematics and faunistics of selected taxa of grassland arthropods will make extensive use of the resources already housed in collections. Proper attention to label data of material added to collections will facilitate the use of the specimens in these studies (Wheeler et al. 2001). Structured sampling programs will provide specimens of use in systematic studies as well as in ecological investigations. Targeted collecting may also be necessary to obtain sufficient specimens and ecological data of taxa not normally obtained using standard techniques. Such taxa include parasites or parasitoids for whom host data are required and herbivores that are internal feeders (gall inhabitants, leaf miners, stem borers) or for whom host plant identification is required.

Expected Results and Products
Coordinated activities under the Grasslands Project will result in information of use to many different parties. Although much of the information acquired will appear in book form, some of the results will be published in specialist scientific journals, while other findings will appear in semi-popular literature or in a form useful to agricultural and environmental organizations and users. Samples of expected results are outlined below.

Core Knowledge and Infrastructure
Specimens and their associated data are the raw data of biodiversity research. As such, the Grasslands Project is dependent upon the core knowledge generated by such collections of data.

Reference Collections and Research Specimens. A key objective of the project is to obtain research and reference collections of grassland arthropods. Although many of the specimens collected by individual researchers will be housed at their respective institutions, a growing number of institutions do not maintain insect collections. Government collections (e.g., Canadian National Collection of Insects, Agriculture and Agri-Food Canada Research Stations, Canadian Museum of Nature), provincial museums (e.g., Provincial Museum of Alberta, Royal British Columbia Museum, Royal Ontario Museum) and university collections (e.g., Lyman Entomological Museum, University of Guelph Collection, J.B. Wallis Museum, Strickland Museum) will be the custodians of many of the specimens collected in the course of the project. The network of Canadian research collections will benefit from access to these specimens.

Establishment of reference collections of grassland arthropods will facilitate the identification of specimens collected in subsequent studies and surveys. Such collections are also a powerful tool in demonstrating the great diversity of arthropods in apparently ‘uniform’ habitats.

The true value of specimens collected in the course of biodiversity projects is often not realized until years later when they become vital data in subsequent systematic, genetic or ecological studies. The specimens collected in the Grasslands Project will enrich the research collections of a number of Canadian institutions and permit access to this material by researchers from Canada and around the world. The value of this material is compounded even further with the realization that continued degradation of grassland habitats may extirpate the remaining populations of many of these species in Canada.

Electronic Databases. Given that much of the research conducted under the auspices of the Grasslands Project will be ongoing and long-term, it is clear that the data collected will continue to grow, be analyzed, and be available for future studies. The most desirable medium for managing such long term data is an electronic database, which can be updated, modified, searched and linked to other, similar databases for analysis. Individual researchers or institutions will maintain the database on their taxa or habitat of interest, as is usual. However, no single database is as informative or powerful as an interconnected group of similar resources. Efforts will be made to ensure that the separate databases on grassland arthropods are in a format that is compatible between institutions and computer systems, and that the databases are accessible and searchable via the Internet from remote locations. Great progress is being made in the development if interconnected online databases of biodiversity data and the Grasslands Project could become an early leader in the use of the available technology.

Core Scientific Products
Establishing collections of specimens and databases will provide the scientific infrastructure for syntheses on the fauna of grasslands. These syntheses will be disseminated to the scientific community through multi-authored books and individual research papers.

Ecology of Arthropods in Canadian Grasslands. The diversity of arthropods in Canadian grasslands is such that an exhaustive study of the entire fauna is unrealistic in the short term. However, there are some defined habitats and regions that have been, and are currently, the focus of comprehensive faunistic and ecological studies. Synthetic and/or quantitative treatments of arthropod diversity in these habitats are feasible. Potential chapters will cover topics such as arthropods of selected habitats (e.g., palouse grasslands, Yukon grasslands, tall grass prairies, grassland alvars and savannas, riverine ecosystems) or of sites where extensive sampling has been conducted (e.g, National and Provincial Parks, Department of National Defense lands). Other chapters will focus on interactions between arthropods and other taxa of arthropods, non-arthropod animals, or plants.

Biodiversity of Arthropods in Canadian Grasslands. This major volume is intended as an overview of the systematics, and diversity of the dominant arthropod taxa in Canadian grasslands. Basic systematic and faunistic knowledge provides the framework upon which valid studies in ecology, conservation and management are based. Specific chapters dealing with selected taxa dominant in grasslands will be included, as well as more synthetic chapters on such topics as adaptations of grassland insects and postglacial evolution and distribution of grassland arthropods.

Arthropods and Altered Grassland Ecosystems. The high degree of human mediated alteration in Canada's grassland ecosystems makes it crucial to understand the role of the arthropods that remain in such areas. Many of the species in these altered grasslands are considered pests, but it is also important to determine the roles of predacious and parasitic arthropods in control of pest species, the role of pollinators of crop plants, and the role of arthropods in soil conditioning. This major volume will be of interest to those concerned with the impact of arthropods in agricultural systems, faunal changes associated with habitat alteration, and the conservation and restoration of grassland ecosystems.

Individual Taxonomic and Ecological Papers. Based on estimates of the number of undescribed arthropod species in Canada, it is inevitable that many species collected in the course of the Grasslands Project will be new to science. Furthermore, no current keys exist to facilitate identification of many taxa with known species. The collections and field data compiled in the course of this project will provide the necessary material on which taxonomic descriptions and monographs, identification keys, and ecological research papers will be based.

Selected Applications
One of the great benefits of basic biological research is that it provides a framework upon which a wide range of applications can be based. The knowledge and products arising from the Grasslands Project will enable applied research and spin-off products in a number of different sectors. Understanding the nature and function of an ecosystem permits more accurate predictions on how that system will respond to changes.

At the species level, knowledge of regional diversity will allow workers to identify species at risk, which will in turn help to identify areas that should be targeted for conservation. This knowledge will also facilitate informed decisions on land-use planning, particularly in cases where the choice between multiple alternatives has implications for species or habitats at risk. In situations where land use decisions have already been made, arthropods will prove valuable in monitoring ecosystem health, given their broad range of responses to change. Finally, in cases where poor decisions in the past have resulted in degraded ecosystems, knowledge of the role of arthropods will be absolutely crucial in restoration attempts.

There are a variety of human impacts to which arthropods respond more quickly and more predictably than other taxa. Thus, understanding the responses of grassland species to changes will allow us to interpret and predict the effects of fire, grazing, etc. Greater understanding of grassland arthropod dynamics will permit more accurate predictions of the potential effects of newly recognized pest species, or newly introduced biological control agents.

Funding and Support
A project of this magnitude will require substantial financial support. Three main components of the project will require funding: field research, specimen processing and collection management; data management and analysis; and publication and dissemination of results.

The fieldwork and laboratory research of individual collaborators in the project will often be partly supported by research grants from government agencies (e.g., NSERC) or their home institution (e.g., museums, government laboratories). However, additional sources of public and corporate funding will be necessary. It is increasingly evident that a major cost of biodiversity research is in the preparation, curation and maintenance of specimens and in the construction of databases to allow the specimen data to be accessible for analysis. The importance of this component of the research is, unfortunately, vastly under appreciated by most funding agencies. This means that other sources must be sought to support the personnel engaged in these duties.

The Survey and Grasslands Subcommittee will explore sources of funding through federal and provincial government agencies, conservation agencies and foundations, resource and utility industries, agricultural organizations, etc. It will likely be more feasible to seek group funding for collaborative efforts on defined subsets of the overall project. Although some mechanisms currently exist for funding collaborative research (e.g., NSERC strategic grants and collaborative grants) additional sources, including non-traditional avenues will be sought. The possibility of the Survey applying for block funding which could then be distributed to individual researchers will be explored. There will be considerable costs associated with the publication of the large volumes resulting from this project. Planning must begin soon to ensure sufficient contributions by sponsors and supporting agencies are in place to produce and distribute these volumes.

References

Anderson, T.W., R.W. Mathewes and C.E. Schweger. 1989. Holocene climatic trends in Canada with special reference to the Hypsithermal interval. Pp. 520-528 In R.J. Fulton (Ed.). Quaternary Geology of Canada and Greenland. Geology of Canada No. 1. Geological Survey of Canada, Ottawa.

Blades, D.C.A. and C.W. Maier. 1996. A survey of grasslands and montane arthropods collected in the southern Okanagan region of British Columbia. Journal of the Entomological Society of British Columbia 93: 49-73.

Boucher, S. and T.A. Wheeler. 2001. Diversity of Agromyzidae (Diptera) in disjunct grasslands of the southern Yukon Territory. The Canadian Entomologist 133: 593-621.

Brooks, A.R. 1958. Acridoidea of Southern Alberta, Saskatchewan and Manitoba (Orthoptera). The Canadian Entomologist, Supplement 9: 3-32.

Danks, H.V. 1996. How to assess biodiversity without wasting your time. A brief from the Biological Survey of Canada (Terrestrial Arthropods). Biological Survey of Canada Document Series No. 5.

Danks, H.V. and N.N. Winchester. 2000. Terrestrial arthropod biodiversity projects – building a factual foundation. A brief prepared by the Biological Survey of Canada (Terrestrial Arthropods). Biological Survey of Canada Document Series No. 7.

Evans, E.W. 1988. Grasshopper (Insecta: Orthoptera: Acrididae) assemblages of tallgrass prairie: influences of fire frequency, topography, and vegetation. Canadian Journal of Zoology 66: 1495-1501.

Finnamore, A.T. (Editor). 1996. The SAGE Project: A workshop report on terrestrial arthropod sampling protocols for graminioid ecosystems. EMAN and Partners Publications. www.cciw.ca/eman-temp/reports/publications/sage

Finnamore, A.T. 1998. Results from grasslands: aculeate wasps from Canadian Forces Base Suffield (Hymenoptera: Chrysididae, Vespoidea, and Apoidea: Sphecidae). Newsletter of the Biological Survey of Canada (Terrestrial Arthropods) 17: 44-57.

Finnamore, A.T., V.M. Behan-Pelletier and N.N. Winchester. 1998. Protocols for measuring biodiversity: Arthropod monitoring in terrestrial ecosystems. EMAN and partners publications. www.cciw.ca/eman-temp/reports/publications

Finnamore, A.T. and D. Buckle. 1999. Arthropod component report. The stinging wasps (Hymenoptera: Chrysidoidea, Vespoidea, Apoidea) and spiders (Araneae). Canadian Forces Base Suffield National Wildlife Area. Wildlife Inventory. The Provincial Museum of Alberta. 197 pp.

Hamilton, K.G.A. 1994. Leafhopper evidence for origins of northeastern relict prairies (Insecta: Homoptera: Cicadellidae). Pp.61-70 In R.G. Wickett, P.D. Lewis, A. Woodliffe and P. Pratt (Eds.). Proceedings of the Thirteenth North American Prairie Conference. Preney Print & Litho, Windsor.

Hamilton, K.G.A. 1995. Evaluation of leafhoppers and their relatives (Insecta: Homoptera: Auchenorhyncha) as indicators of prairie preserve quality. Pp. 211-226 In D.C. Harnett (Ed.). Proceedings of the Fourteenth Annual North American Prairie Conference: Prairie Diversity. Kansas State University, Manhattan.

Hamilton, K.G.A. 1997. Leafhoppers (Homoptera: Cicadellidae) of the Yukon: dispersal and endemism. Pp. 337-375 In H.V. Danks and J.A. Downes (Eds.). Insects of the Yukon. Biological Survey of Canada (Terrestrial Arthropods), Ottawa.

Knapp, A.K.. J.M. Blair, J.M. Briggs, S.L. Collins, D.C. Hartnett, L.C. Johnson and E.G. Towne. 1999. The keystone role of bison in North American tallgrass prairie. Bioscience 49: 39-50.

Lehmkuhl, D.M. 1980. Temporal and spatial changes in the Canadian insect fauna: patterns and explanation, the Prairies. The Canadian Entomologist 112: 1145-1159.

Marshall, S.A., R.S. Anderson, R.E. Roughley, V.M. Behan-Pelletier and H.V. Danks. 1994. Terrestrial arthropod diversity: Planning a study and recommended sampling techniques. A brief. Bulletin of the Entomological Society of Canada 26(1) (Supplement).

Matthews, J.V., Jr. 1979. Tertiary and Quaternary environments: historical background for an analysis of the Canadian insect fauna. Pp. 31-86 In H.V. Danks (Ed.). Canada and its insect fauna. Memoirs of the Entomological Society of Canada 108: 1-573.

Matthews, J.V., Jr. 1982. East Beringia during late Wisconsin time: A review of the biotic evidence. Pp. 127-156 In D.M. Hopkins, J.V. Matthews Jr., C.E. Schweger and S.B. Young (Eds.). Paleoecology of Beringia. Academic Press, New York.

Moss E.H. 1952. Grassland of the Peace River region, western Canada. Canadian Journal of Botany 30: 99-123.

Ritchie, J.C. 1975. The late-Quaternary vegetational history of the Western Interior of Canada. Canadian Journal of Botany 54: 1793-1818.

Roughley, R.E. 2001. Tallgrass prairie and the use of fire as a biodiversity and conservation and management tool on the St. Charles Rifle Range, Department of National Defence, Winnipeg, Manitoba. 81 pp.

Scudder, G.G.E. 1993. Geographic distribution and biogeography of selected species of xeric grassland-adapted Nearctic Lygaeidae in western North America (Insecta: Heteroptera). Pp. 75-113 In G.E. Ball and H.V. Danks (Eds.). Systematics and entomology: diversity, distribution, adaptation, and application. Memoirs of the Entomological Society of Canada 165: 1-272.

Turnbull, A.L. 1979. Recent changes to the insect fauna of Canada. pp 180-194 In H.V. Danks (Ed.). Canada and its insect fauna. Memoirs of the Entomological Society of Canada 108: 1-573.

Wheeler, T.A., J.T. Huber and D.C. Currie. 2001. Label data standards for terrestrial arthropods. A brief prepared by the Biological Survey of Canada (Terrestrial Arthropods). Biological Survey of Canada Document Series No. 8.

Whitcomb, R.F., A.L. Hicks, H.D. Blocker and D.E. Lynn. 1994. Biogeography of leafhopper specialists of the shortgrass prairie: evidence for the roles of phenology and phylogeny in determination of biological diversity. American Entomologist 40: 19-35.

White, K.M. 2001. The effect of a grassland fire on a prairie arthropod community. Arthropods of Canadian Grasslands Newsletter 7: 21-25.

Appendix 1. Classification and Distribution of Canadian Grasslands
Four major types of grasslands occur in the prairie ecozone of Canada; three of these, dry mixed grass, mixed grass and tall grass prairie, are at the northern limit of a biome that extends south through the central United States to northern Mexico. The fourth, fescue grassland, is more restricted and disjunct in its distribution. Other grassland types, such as palouse grasslands, savannas and alvars, are not well-represented in the prairie ecozone itself, but are characteristic of the eastern and western limits of Canadian grasslands.

Dry Mixed Grass Prairie (‘Short Grass’ Prairie) (Fig. 2) occurs in southeastern Alberta and southwestern Saskatchewan where rainfall and evaporation are less favourable. Dominant grasses are Bouteloua gracilis (blue grama) Buchloë dactyloides (buffalo grass) and Stipa comata (needle and thread). In seriously overgrazed areas, Opuntia polyacantha (prickly pear) and Artemisia frigida (pasture sage) are common. The term ‘short grass prairie’ is often used to describe this grassland type; however, some authors point out that this term does not strictly apply in Canada because these areas are actually xeric mixed grasslands which have been overgrazed to the point that short grass species dominate.

Mixed Grass Prairie (Fig. 2) occurs in southern Alberta and Saskatchewan with Stipa comata (needle and thread) Festuca altaica (northern rough fescue), Festuca occidentalis (Idaho fescue), Danthonia parryii (Parry’s oat grass) and Danthonia intermedia (wild oat grass) being the dominant grasses. Outliers of mixed grass prairie are also found in the Peace River district of northwestern Alberta where Stipa spartea (porcupine grass) dominates.

Tall Grass Prairie (Fig. 2) is found only in southern Manitoba, the Rainy River-Fort Frances area of northwestern Ontario and southwestern Ontario where precipitation and groundwater are sufficient to allow trees such as oaks and poplars to become established, but frequent fire and herbivory keep them from encroaching on the open areas. Canadian areas of tall grass prairie are extensions of the so-called Prairie Peninsula of the USA. Dominant grasses in Manitoba and Ontario tall grass sites include Andropogon gerardii (big bluestem), Panicum virgatum (switchgrass), Schizachyrium scoparium (little bluestem) and Spartina pectinata (cord grass). Non-grass species such as sedges and composites are diverse and sometimes dominant in tall grass prairies.

Fescue Grassland occurs in three well-defined areas (Fig. 2). The largest is found in a broad swath along the moister, northern border of mixed grass prairie in Alberta west of Edmonton, across central Saskatchewan and Manitoba to just east of Winnipeg. This ecotone, the Aspen Parkland ecotone, forms the transition between the boreal forest of the north and the grasslands to the south and is characterized by groves of Populus tremuloides (aspen poplar). Fescue grassland is also found in the Cypress Hills of southeastern Alberta and southwestern Saskatchewan and the foothills of the Rocky Mountains in southwestern Alberta. The third area is in sub-boreal and boreal regions, ranging from the northern Rocky Mountains in Alberta westward through British Columbia and north to the Yukon. The dominant grass in the fescue grasslands of the Aspen Parkland ecotone is Festuca campestris (rough fescue). Festuca altaica (northern rough fescue) is dominant in the other areas of fescue grassland.

Bunch Grass or Palouse Grasslands are grasslands of the southern interior of British Columbia. This unique region is a northern extension of the intermontane grassland area of the western United States. These discontinuous grasslands occur in several of the southern interior valleys of British Columbia (e.g., Kettle Valley; Okanagan Valley, Similkameen River Valley, Thompson River Valley, Nicola River Valley and adjacent plateau areas, middle Fraser and lower Chilcotin River valleys). Smaller palouse grasslands occur in the Kootenay and Columbia River valleys in southeastern British Columbia. The dominant grasses in these areas include Agropyron spicatum (bluebunch wheatgrass), Poa secunda (Sandberg’s bluegrass), P. cusickii (Cusick’s bluegrass), Koeleria cristata (June grass), Stipa comata (needle-and-thread grass), Festuca scabrella (rough fescue) and Festuca idahoensis (Idaho fescue). Trees associated with this region include Pseudotsuga menziesii var. glauca (Douglas fir) and Pinus ponderosa (Ponderosa pine) and the shrub Artemisia tridentata (sagebrush). Three dominant climax types, defined by a combination of temperature, precipitation, altitude and latitude are recognized within these grasslands. Lower grasslands are hot and dry sagebrush-bunchgrass in the valley bottoms; middle grasslands are a less arid band of steppe above the lower grassland; upper grasslands are cooler, moister steppe that extends onto the plateau. Extreme overgrazing in all three grassland areas has resulted in invasion by weedy species such as Bromus tectorum (cheatgrass) and Centaurea species (knapweed)

Savannas and Grassland Alvars represent the eastern outliers of the prairie grasslands in Manitoba and southern Ontario. Savannas are characterized by an understory dominated by prairie-associated grasses, with an open forest of oaks (Quercus spp.) or pines (Pinus spp.). Alvar grasslands and alvar savanna grasslands are similar in appearance to savannas. Savannas and alvars in the Great Lakes region of Ontario have a number of plant species typical of tall grass and mixed prairies including Andropogon gerardii (big bluestem), Schizachyrium scoparium (little bluestem), Sporobolus heterolepis (prairie dropseed) and Panicum virgatum (switchgrass). The major difference between savannas and alvars and the western grasslands is the substrate; alvar grasslands are characterized by a thin layer of soil overlying limestone bedrock while Ontario savannas are associated with well-drained sandy soils. The physical nature of these substrates limits the growth of trees and contributes to the open, prairie-like nature of these habitats.

Selected grassland references

Archibold, O.W. and M.R. Wilson. 1980. The natural vegetation of Saskatchewan prior to agricultural settlement. Canadian Journal of Botany 58: 2031-2042.

Axelrod, D.I. 1985. Rise of the grassland biome, central North America. Botanical Review 51: 163-201.

Barbour, M.G. and W.D. Billings (Editors). 1988. North American terrestrial vegetation. Cambridge University Press, New York.

Bird, R.D. 1927. A preliminary ecological survey of the district surrounding the Entomological Station at Treesbank, Manitoba. Ecology 8: 207-220.

Bird, R.D. 1961. Ecology of the aspen parkland of western Canada. Canada Department of Agriculture. x + map + pp 1-155, Ottawa.

Catling, P.M. and V.R. Brownell. 1995. A review of the alvars of the Great Lakes region: distribution, composition, biogeography and protection. Canadian Field-Naturalist 109: 143-171.

Coupland, R.T. 1950. Ecology of mixed prairie in Canada. Ecological Monographs 34: 271-315.

Coupland, R.T. 1952. Grassland communities of western Canadian prairies- climax and subclimax. Proceedings of the Sixth International Grasslands Congress: 625-631.

Coupland, R.T. 1992. Natural Grasslands. Introduction and Western Hemisphere. Ecosystems of the World 8A. Elsevier. Amsterdam.

Coupland, R.T. and T.C. Brayshaw. 1953. The fescue grassland in Saskatchewan. Ecology 34: 386-405

Finnamore, A.T. 1992. Arid grasslands – biodiversity, human society, and climate change. Canadian Biodiversity 2: 15-23.

Hamilton, K.G.A. (1990) Grasslands of Ontario and surrounding areas. Arthropods of Canadian Grasslands Newsletter 5, 2-10.

Knapp, A.K., J,M. Briggs, D.C. Hartnett, and S.L. Collins (Editors). 1998. Grassland Dynamics. Long-Term Ecological Research in Tallgrass Prairie. Oxford University Press, New York & Oxford. xvi + 364 pp.

Matthews, J.V. Jr. 1982. East Beringia during late Wisconsin time: a review of the biotic evidence. Pp. 127-156 In D.M. Hopkins, J.V. Matthews, Jr., C.E. Schweger and S.B. Young (Eds). Paleoecology of Beringia. Academic Press, New York.

Moss, E.H. 1952. Grassland of the Peace River region, western Canada. Canadian Journal of Botany 30: 99-123.

Moss, E.H. and J.A. Campbell. 1947. The fescue grassland of Alberta. Canadian Journal of Research, (C) 25: 209-227.

Risser, P.G., E.C. Birney, H.D. Blocker, S.W. May, W.J. Parton and J.A. Wiens. 1981. The true prairie ecosystem. Hutchinson Ross, Stroudsburg.

Scott, G.A.J. 1995. Canada’s Vegetation: A World Perspective. Chapter 5. Prairie (Steppe). McGill-Queen’s University Press, Montreal.

Spilsbury, R.H. and E.W. Tisdale. 1944. Soil-plant relationships and vertical zonation in the southern interior of British Columbia. Scientific Agriculture 24: 395-436.

Vetter, M.A. 2000. Grasslands of the Aishihik-Sekulum Lakes area, Yukon Territory, Canada. Arctic 53: 165-173. 

Prepared in 2002 on behalf of the Biological Survey by:

Joseph D. Shorthouse, Department of Biology, Laurentian University, Sudbury, Ontario
and
Terry A. Wheeler, Department of Natural Resource Sciences, McGill University, Macdonald Campus, Ste-Anne-de-Bellevue, Quebec, H9X 3V9

This page last updated 02/03/2010