Dawn R. Bazely

Do grasses fight back? The case for antiherbivore defences

In the past, discussion about grass-grazer interactions has tended to centre on whether they represent some sort of mutualism. However, intense grazing pressure is more likely to have selected for the presence of various antiherbivore defences in grasses. Many grasses contain silica, which functions in some cases as a physical defence. Others contain various secondary compounds which have negative effects on both invertebrate and vertebrate herbivores. Much recent evidence suggests that plants with higher levels of these defences deter herbivores more effectively than plants without them.

Outcomes of longterm deciduous forest restoration in southwestern Ontario, Canada

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 Pelee 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.

Responses of brambles, Rubus vestitus, to herbivory

We investigated the effect of fertilisation and multiple episodes of simulated herbivory on the prickliness of bramble, Rubus vestitus. The prickliness of fertilised, uncut plants was significantly greater than that of plants in all other treatments. Our results indicate that prickle production is constrained by resource availability, with brambles allocating resources to growth under intense herbivory. Isozyme electrophoresis of plants collected from Wytham Woods, Oxford, UK, failed to detect any variation, suggesting that observed variation in prickliness may be primarily the result of phenotypic plasticity. In our experiments, however, we observed significant variation in prickliness among putative genotypes.

Are legislative frameworks in Canada and Ontario up to the task of addressing invasive alien species

As a signatory to the international Convention on Biological Diversity (CBD), Canada has committed to prevent, control, and eradicate invasive alien species (IAS). Yet, despite developing policy on biodiversity and IAS, the federal government has been criticized for its inaction on biological invasions over the past decade. In Canada’s most populous province, Ontario, similar concerns have been raised about the provincial government’s approach to dealing with IAS. The ongoing criticism of government response suggests that an effective legislative framework to guide and coordinate action on IAS may be lacking in Canada. In this paper, we examined how well existing legislation at the federal and Ontario levels addresses IAS threats, and thus contributes to CBD commitments. We reviewed a total of 98 pieces of legislation, comprised of 55 federal acts, two federal omnibus bills, and 41 Ontario acts. Of these, 20 federal and 12 Ontario acts were found to cover IAS either intentionally or incidentally, but IAS was not the central focus of most legislation. No consistent terminology existed across legislation referring to IAS, further highlighting a lack of focus on the issue. Legislation on IAS was administered by several different ministries both federally and in Ontario, but coordination of action among agencies was not explicitly addressed in laws and regulations. While many acts provided broad powers of enforcement, most provisions were not directly linked to IAS prevention and management. In general, Canada’s legislative framework on IAS is fragmented, and this complicates the development of a coordinated approach to the problem.

A Human Security Framework for the Management of Invasive Nonindigenous Plants

Abstract Few individuals or governments have suggested that invasions by nonindigenous species are relevant to the broader issue of human security, despite a growing awareness of the ecological, economic, and societal impacts associated with invasive nonindigenous species (INIS). We propose that by framing management actions in a human and environmental security context, the threats (and benefits) posed by INIS to individuals and communities can be explicitly articulated and debated. This framework allows multiple stakeholders to bring their concerns to bear upon specific policy, and attempts to integrate broad environmental concerns within its parameters. We use the case of ecosystem-based management of invasive nonindigenous plants as an example of the utility of a human security framework. The dominant management approach to these species remains focused on the individual species, despite increasing calls for the implementation of ecosystem-based management strategies. Ecosystem-based management is supported by generalized and widely accepted mechanisms of plant community dynamics, such as succession, disturbance, and interspecific competition, but these scientific arguments do not consistently carry weight at the policy level and with the broader public. A human security framework may provide an approach for overcoming this resistance by placing the debate over management within the social and political context of the wider community. Overall, human security can allow applied ecologists to be better positioned to meet the challenges of communicating the need for science-based management.

Strengthening Resilience by Thinking of Knowledge as a Nutrient Conecting the Local Person to Global Thinking

In April 2009, we held an international conference at York University in Toronto, Canada, billed as Ecojustice: How Will Disenfranchised Peoples Adapt to Climate Change? (Dubreuil, 2009; Klenk, Bazely, & Perkins, 2010). A diverse group of activists and academics that work with NGOs from the Global South and North came together to discuss the challenges of adapting to climate change.

Human Security in the Arctic: The IPY GAPS Project

During the usual rush of “Arctic” themed conferences in the fall of 2014, human security in the Arctic was on the agenda. The Transatlantic Science Week in Toronto, Canada, arranged a panel that looked at non-state security challenges in the Arctic, ranging from search and rescue issues to health, food, identity, and environmental security