Conservation and Restoration
Factors influencing farmers’ concerns regarding bovine tuberculosis in wildlife and livestock around Riding Mountain National Park
By Ryan K. Brook & Stephane M. McLachlań
Despite intensive efforts over the last century to eradicate bovine tuberculosis (TB) in North America, several hotspots of infected wildlife and livestock remain, raising concerns that the disease will never be eradicated. The stress and frustration for a farmer caused by having a herd test positive for TB or living in an infected region can be substantial. The goal of this study was to investigate the concerns of farmers around Riding Mountain National Park (RMNP) regarding the presence of TB in wildlife and livestock and conduct an exploratory analysis of causal factors. Data were collected from 786 farmers within 50 km of RMNP using a mail-back questionnaire. Overall, farmers indicated a high level of concern toward diseases in both wildlife and cattle relative to other concerns. The spatial variables that had the greatest influence on TB concern were both the distance of farms to the RMNP boundary and distance of farms to previous cases of TB. The most important aspatial factor associated with high TB concern was the frequency with which farmers observed elk on their land. These results underscore the important differences between ‘objective’ measures of risk, such as epidemiological estimates of disease prevalence, and subjective measures of disease concern, such as risk perception and acceptability of management actions. Written responses suggest that concerns regarding disease may affect how farmers view wildlife on their land and their relationship with neighbouring protected areas. Management activities that reduce the frequency of elk interactions with farms, but also recognize the complex relationship that farmers have with wildlife and protected areas, will be most effective in mitigating farmer concern regarding this important problem.
By Ryan K. Brook
Successful mitigation of human-wildlife conflicts requires an approach that incorporates both the ecological aspects of wildlife and the social considerations of the affected stakeholders and these must be considered in an integrated fashion at multiple temporal and spatial scales. In this dissertation, I examine the relationship between farmers around Riding Mountain National Park (RMNP) in southwestern Manitoba and the regional elk (Cervus elaphus) population, in order to better understand and resolve these long-standing conflicts more effectively. Local perspectives were documented throughout this study, initially through 40 community nieetings in 2000 and 2001 prior to formal data collection, then through a mail-out survey in2002, and later through participatory mapping exercises from 2003 to 2006. A longitudinal analysis of historical information regarding elk-agriculture conflicts using the interviews and government letter files indicated that diverse types of conflicts have occurred annually for the lasl l2T years. Issues related to bovine tuberculosis (TB) in elk in the last l5 years have been some of the most intense conflicts ever occurring, but these are based on previous conflicts and they have further undermined the already strained relationship between farmers and RMNP. The most important factor associated with high concern regarding bovine TB was the frequency that farmers observed elk on their land. To examine the biophysical aspects of elk interactions with agriculture, 212 wild elk were captured from 2002-2005 using a net-gun fired frorn a helicopter and given a GPS satellite collar (n:25) or VHF transmitter (n:187). Overlap in space use between elk and cattle was high in summer and low in winter based on both the collar data and local knowledge, though farmers identified higher levels of overlap throughout the year. During the spring elk calving period, the home ranges of 73o/o of the parturient elk remained entirely within protected areas, while 6Yo were exclusively on farmland, and 2lYo included both. The propottion of the elk population calving on farmland continues to increase from near zero in the 1970s. Hay yard barrier fences are the most effective and widely accepted management tool in use to mitigate elk-agriculture conflict, but modifications to the process of allocating and monitoring fences are needed. Indeed, all aspects of the management of elk-agriculture interactions require greater levels of communication and collaboration between government agencies and local stakeholders. I also advocate taking an adaptive, science-based approach to managing human-wildlife conflicts that focuses on both the social and natural sciences as mutually contributing to our understanding of the problems and generating meaningful solutions. This is one of few studies that makes use of local knowledge and conventional ecological data together, and demonstrates the contributions of both in better understanding the temporospatial aspects of wildlife-human conflicts and their socioeconomic and conservation implications.
By S.M. McLachlan & A.L. Knispel
Ecological restoration is important in mitigating degradation and habitat loss of tallgrass prairie in North America. In 2002, we assessed the progress of a long-term tallgrass prairie restoration initiated in 1987 in southern Manitoba (Canada). Nine restoration and three reference sites were examined, as was a neighbouring site of future restoration that is now used for agriculture. Vegetation diversity, species composition, and associated soil properties were compared among restoration and reference sites, and changes associated with restoration identified. Restoration had a substantial effect on diversity and species composition, although restoration sites had significantly lower native and higher exotic diversity than reference sites. Overall and native diversity decreased over time, as both exotic and seeded native species were lost from the restoration sites. Particularly vulnerable were native forb species, which represent much of the diversity of prairie habitats. Forb presence was negatively associated with that of warm season native grasses, especially Andropogon gerardii (big bluestem). Similarity of restoration and reference vegetation increased over time, particularly for seeded native graminoids. When species that had been seeded elsewhere and had colonized restorations were examined, similarity between restoration and reference also increased with time, suggesting that older sites may be self-propagating. No significant differences in soil properties variables were observed among restoration sites, indicating that changes in these factors are slow relative to vegetation changes. Although time-since-restoration had a substantial impact on diversity and species composition, this habitat will require ongoing restoration.
By Shaun F. Moffatt & Stéphane M. Mclachlan
Riparian forests have been adversely affected by human land use and are threatened across North America. Seed banks play an important role in the maintenance and regeneration of forests, yet effects of land use and fragmentation on forest seed banks remain poorly understood. In 1998 and 1999, we assessed impacts of human disturbance on the diversity and species composition of seed banks in upland portions of riparian forests along an urban-rural gradient in southern Manitoba. Twenty-five forest fragments were categorized according to the following land-use: urban, suburban, high-intensity rural, low-intensity rural, and relatively undisturbed reference classes. Seeds of weedy and exotic species were positively associated with fragmentation, high levels of disturbance, and dry alkaline soils. Seed bank species diversity was lower in urban sites than in rural sites, and the similarity of urban to reference sites was significantly lower than that of rural to reference sites. In contrast, the proportion of exotic to native species richness was highest in seed banks of urban sites. Exotic species Hackelia virginiana and Poa pratense were associated with urban and suburban sites, respectively. Six exotic species were unique to urban sites; these included Hesparis matronalis and Plantago major. In contrast, many of the frequently encountered native species were absent from urban sites; these included Anemone canadensis and Rubus idaeus. These changes in seed bank may affect the ability of riparian forests to recover from adverse impacts associated with urban development and agriculture.
By Jing Ma , Keith W. Hipel & Stéphane M. McLachlan
A transboundary conflict between Canada and the United States due to slag contamination in Lake Roosevelt is formally studied using the Graph Model for Conflict Resolution. Three key decision makers (DMs) were identified: 1) Teck Cominco, the largest mining, mineral processing and metallurgical company in Canada; 2) the United States Environmental Protection Agency; and 3) the Colville Indian Tribes, whose traditional territories are located in the Lake Roosevelt area. After a careful background investigation, the conflict among these three groups is modeled by identifying three key DMs, potential courses of action for each DM, and the relative preferences of each DM with respect to the states or scenarios that could occur as of May 2006, just before the settlement agreement was signed. Subsequently, a stability analysis is carried out and several strong equilibria or potential solutions to the conflict are identified. The analytical results verify the suitability of the developed analytical model, suggest mutual agreements between the stakeholders as a potential solution for the conflict, and highlight the importance of establishing new or strictly enforcing existing water policies in order to resolve current conflicts and to avoid any future controversies.
By Shaun F.H. Moffat
Extensive landscape modification from surrounding land use has led to the decline of riparian forests across North America. An urban – rural gradient was used to assess the impact of land use on riparian forests along the Assiniboine River. Above ground flora and seed bank were examined and species- and guild-level indicators of disturbance identified. Twenty-five sites were categorized according to land use, and included urban, suburban, high intensity rural, low intensity rural, and relatively high quality reference forests. Changes in herbaceous, shrub, and tree species composition and diversity were related to landscape level measures of disturbance that included the proportion of surrounding land use, forest patch size, connectivity, and area:perimeter ratio. Urban forests were highly fragmented and the most adversely affected by surrounding land use. They were small, isolated, lacked interior, and charac terizedby relatively dry and alkaline soils. They had the lowest native and overall understorey and seed bank species diversity, highest proportion of exotic species, and the lowest seed density. Indicators of disturbance, typically opportunistic species, were significantly more common in these urban forests and included Solanunt dulcantarq, Rhamnus cathartica, and Lonicera tartarica. Suburban forests were less disturbed, but had been recently subjected to extensive development-related clearing and fragmentation. Although reference sites were relatively large and exhibited greater connectivity, there was little difference in species composition among low and high intensity rural and reference sites. Indicators of high integrity forest, typically nrlnerable species, were significantly more frequent in these non-city land use types, and included Rubus idaeus, Carex spp., and Galium triflorum. Generalists dominated (69 %) the understorey community, whereas opportunistic (15 %) andvulnerable (16 %)species were relatively less common. Opportunistic species tended to be exotic, woody and annual, and effective dispersers (i.e. endozoochores). In contrast, wlnerable species tended to be native, perennial, and ineffective dispersers (i.e. barichores or anemochores). In total 197 taxa were identified in the above ground flora, compared to 90 taxa in the seed bank. Of the latter, the three most frequent species, Poa pratensis, Sonchus arvensis, and Cirsium arvense, were all exotic. These results suggest that landscape measures of disturbance, and related changes in environment, may be confidently used to assess the impacts of land use along urban-rural gradients. Changes in seed bank of this important riparian forest system suggest that the cur¡ent decline will continue especially if future forest regeneration is solely dependent upon the seed bank. Opportunistic and Vuulnerable species, and their associated guilds can be used as effective indicators of disturbance and forest integrity and be used to select and monitor forests for further protection or active management.
By Astrid V. Stronena, Ryan K. Brook, Paul C. Paquet & Stéphane M. McLachlan
The potential for disease transmission between wild and domestic animals may interfere with wildlife and habitat conservation on lands surrounding protected areas. Recently, possible transmission of bovine tuberculosis (Mycobacterium bovis) from wild ungulates to domestic livestock has affected the Riding Mountain National Park region in Manitoba, Canada. Wolf (Canis lupus) predation on ungulate populations may help lessen the risk of disease transmission to livestock. We conducted an exploratory analysis of causal factors associated with farmer attitudes toward observing wolves on their farms. A survey to 4220 farms within 50 km of the Park resulted in an adjusted response rate of 25%. We constructed several logistic regression models with factors hypothesized to influence whether farmers agreed with the statement ‘‘I enjoy seeing wolves on my land’’, and three candidate models received reasonable support. Factors most affecting attitudes were, in order of importance, perceived wolf population size, frequency of seeing wolves, perceived seriousness of wolf damage, distance to Park boundary and number of beef cattle (Bos taurus) owned. The factors least influential on attitudes were education and age. Concern over bovine tuberculosis in wild elk also had minimal influence. Of respondents who perceived the wolf population as ‘‘too high’’, 60% were extremely concerned about bovine tuberculosis in wild elk. Although the role of wolf predation as a potential natural regulator of disease in wild ungulates might not be widely recognized in many areas, we believe this provides a unique opportunity to re-examine the significance of maintaining viable wolf populations.
By Bill Thompson & Stéphane McLachlan
With the increase in urbanization globally, there is an increased need to understand the ecology of forest fragments in urban and urbanizing landscapes. Although urban forests are known to be relatively lacking in plants whose seeds are dispersed by ants, little is known about the effects of urbanization on the community composition and behaviour of forest dwelling ants. Ant communities in forest fragments along an urban– rural gradient were described using a rapid quadrat search technique and multivariate analysis. Interactions between the ants and seeds of the myrmecochorous Viola pubescens within a subset of these forests were described using a series of cafeteria experiments. Urbanization was found to be associated with changes in microhabitat characteristics and a concomitant simplification of the ant community. Despite this, the removal rate of V. pubescens seeds actually increased in urban forests, which may be a result of the foraging behaviour of the remaining species.
From the ground up: holistic management and grassroots rural adaptation to bovine spongiform encephalopathy across western Canada
By Stéphane Mclachlan and Melisa Yestrau
This study examines the impacts of and adaptive responses of producers in western Canada to bovine spongiform encephalopathy (BSE), which has adversely affected farmers and rural communities around the world. In particular, it explores how holistic management (HM), with its combined focus on environmental, social, and economic sustainability, might mitigate the effects of BSE. One survey, sent to 835 HM producers and another to 9,740 producers, found both groups experienced devastating impacts as a result of BSE. However, HM producers – because of support from the larger HM community – were much more optimistic about their ability to adapt to BSE and the future of agriculture than their non-HM counterparts. Agronomic responses, especially those associated with rotational grazing and increases in on-farm biodiversity were also important
By Stéphane Mclachlan & D.R. Bazely
At present, forest cover in southwestern Ontario, Canada, remains at less than 5% due to intensive agricultural and urban land use. Although much of the extant forest is increasingly protected by legislation, remnants continue to be degraded by the spread of non-native plant species, overgrazing, and recreational use. Some parks in the region have adopted management programs aimed at mitigating this degradation. Over the last 35 years, cottages and roads at Point PeleÅLe National Park have been removed and sites either passively restored (i.e. road or cottage eliminated and vegetation allowed to regenerate) or actively restored (i.e. road or cottage eliminated, exotic vegetation removed, and native species planted). In 1994 and 1995, we assessed the effectiveness of restoration by comparing the understorey plant communities in 28 restored sites with those in less disturbed reference sites. There was a significant increase (P<0.0001) in the similarity of understorey plant communities between restored and reference sites as time-since-restoration increased. Soil moisture, canopy cover, distance to continuous forest, and site-shape all significantly affected plant species composition. Former road sites recovered significantly (P<0.05) more rapidly than former cottage sites, and the former lawns of passively restored cottage sites were the slowest to recover. Five years following active restoration, non-native ruderal species continued to dominate restored sites. The observed recovery of understorey plant communities in restored sites is attributed to their proximity to natural vegetation, and its function as a seed source. In some sites, recovery is substantial and, assuming present trajectories of change are maintained, we predict that recovery could occur in many mesic sites within the next 20 years. Restoration activity facilitates forest recovery and would appear to have a valuable function in mitigating ongoing conflicts between conservation and human use in this region.
By Stéphane McLachlan & Dawn R. Bazely
Habitat fragmentation has reduced the richness of native species of forests in northeastern North America. Despite recent large-scale increases in forest cover, studies indicate that understory herbaceous plant communities may take many decades to recover. We studied recovery patterns of vegetation following up to 35 years of forest regeneration in restored former cottage and road sites at Point Pelée National Park, Ontario, Canada, to assess the vulnerability of the understory herbaceous species. Overall, there were no significant differences in the diversity of native species between restored and relatively undisturbed reference sites. There was, however, significant among-site variation in the composition of the native species component of these plant communities. When only restored sites were examined, variation in native species composition was associated with time since site restoration, soil moisture, canopy cover, and distance to continuous forest. Native species were assigned vulnerability rankings according to their relative occurrence in reference and restored sites. Spring-flowering herbs, with ant- or gravity-dispersed seeds, were absent from restored sites and were defined as highly vulnerable. In contrast, summer- and fall-flowering herbs, with vertebrate- and wind-dispersed seeds, dominated restored sites and were less vulnerable. Species of low and intermediate vulnerability had colonized restored sites successfully, and the latter should function as indicators of recovery. In contrast, species with high vulnerability rankings had not recovered at all and, because of their limited dispersal ranges, may recolonize restored sites only if they are actively reintroduced.
By Julie M. A. Sveinson
Agriculture and urban development has reduced tallgrass prairie to less than lo/o of its original land cover in southern Manitoba, Canada. Although much of the remaining tallgrass prairie in Manitoba is protected within a single Preserve, it continues to be degraded by the invasion of exotic and woody species, fire suppression, and overgrazing. My overall thesis objective was to assess the role of rehabilitation in tallgrass prairie restoration and more specifically to examine the relative effects of disturbance, soil fertility, and seeding. Two field studies were conducted within the St. Charles Rifle Range (SCRR) and Manitoba Tall Grass Prairie Preserve (MTGPP) to assess these objectives. The impacts of burn-season were examined on a high quality tallgrass prairie located within the SCRR. This four-year study found burn-season to have a substantial impact on diversity and species composition. Fall-burn had the most desirable effect, increasing native graminoid and forb diversity, regardless of time-of-flowering. Summerburn increased both native and exotic graminoid cover. Spring-burn had relatively no effect on species composition and was characterized by woody species. All burn-seasons, except fall-burn, became increasingly similar in species composition to the control over time. Spring-, summer-, and fall-burns had varied but desirable effects on diversity and species composition. In 1999, a long-term experiment was initiated within the MTGPP to assess the role of disturbance (glyphosate, mowing, and fire), soil fertility (ammonium nitrate), and interseeding in rehabilitating degraded tallgrass prairie. Glyphosate had the greatest impact on diversity and species composition. Exotic and weedy native species increased and desirable native species (e.g. Andropogon gerardü) were adversely affected in glyphosate-treated plots. Mowing and fire had less of an effect, in large part because of long-term haying on this site. Fertilizer increased native forbs and graminoids, whereas exotic graminoids decreased. Interseeding with native tallgrass prairie species increased native graminoids and decreased exotic graminoids, but had no effect on forbs. Species composition of glyphosate-treated plots became more similar to the unsprayed and control plots over time, whereas effects of fertilizer and other disturbance factors showed little change. Rehabilitation of tallgrass prairie shows great potential for southem Manitoba. Disturbance and fertilization can have desirable effects, but only when seedbank, above ground vegetation, and site-specific constraints have been identified. Effective techniques in rehabilitation are required if the degradation of remnant and restored tallgrass prairie is to be mitigated.
Understorey indicators of disturbance for riparian forests along an urban-rural gradient in Manitoba
By S.F. Moffatt, S.M. McLachlan
Extensive agricultural and urban development has contributed to the decline of riparian forests across North America. An urban–rural gradient was used to identify species- and guild-level indicators of riparian forest degradation in southern Manitoba. Twenty-five sites were categorized according to urban, suburban, high-intensity rural, low-intensity rural, and relatively high quality reference land use. Generalists, which frequented all land use types, dominated (69%) the understorey community, whereas opportunistic (15%) and vulnerable (16%) species were relatively less common. Opportunistic species, which characterized city sites, tended to be exotic, woody and annual, and effective dispersers (i.e., endozoochores). In contrast, vulnerable species, which characterized non-city sites, tended to be native, perennial, and ineffective dispersers (i.e., barochores or anemochores). Indicators of disturbed forests were opportunistic and positively associated with disturbance measures including connectivity and cover of garbage, and negatively correlated with native and overall diversity. They included exotics Solanum dulcamara, Rhamnus cathartica, and Lonicera tartarica. In contrast, indicators of high-integrity forest were vulnerable, often excluded from urban sites and were negatively associated with disturbance measures and positively correlated with native and overall diversity. They included natives Rubus idaeus, Carex spp., and Galium triflorum. Our results suggest that opportunistic and vulnerable species, and their associated guilds, can be used as effective indicators of disturbance and forest integrity and to identify forest patches that warrant further protection or restoration.