Nora D. Szabo

Bio: Nora D. Szabo is an academic researcher from University of Ottawa. The author has contributed to research in topics: Population & Range (biology). The author has an hindex of 4, co-authored 5 publications receiving 1068 citations.

Pharmaceuticals and personal care products in the environment: what are the big questions?

Abstract: Background: Over the past 10–15 years, a substantial amount of work has been done by the scientific, regulatory, and business communities to elucidate the effects and risks of pharmaceuticals and p...

Generation of Priority Research Questions to Inform Conservation Policy and Management at a National Level

Abstract: Integrating knowledge from across the natural and social sciences is necessary to effectively address societal tradeoffs between human use of biological diversity and its preservation. Collaborative processes can change the ways decision makers think about scientific evidence, enhance levels of mutual trust and credibility, and advance the conservation policy discourse. Canada has responsibility for a large fraction of some major ecosystems, such as boreal forests, Arctic tundra, wetlands, and temperate and Arctic oceans. Stressors to biological diversity within these ecosystems arise from activities of the country's resource-based economy, as well as external drivers of environmental change. Effective management is complicated by incongruence between ecological and political boundaries and conflicting perspectives on social and economic goals. Many knowledge gaps about stressors and their management might be reduced through targeted, timely research. We identify 40 questions that, if addressed or answered, would advance research that has a high probability of supporting development of effective policies and management strategies for species, ecosystems, and ecological processes in Canada. A total of 396 candidate questions drawn from natural and social science disciplines were contributed by individuals with diverse organizational affiliations. These were collaboratively winnowed to 40 by our team of collaborators. The questions emphasize understanding ecosystems, the effects and mitigation of climate change, coordinating governance and management efforts across multiple jurisdictions, and examining relations between conservation policy and the social and economic well-being of Aboriginal peoples. The questions we identified provide potential links between evidence from the conservation sciences and formulation of policies for conservation and resource management. Our collaborative process of communication and engagement between scientists and decision makers for generating and prioritizing research questions at a national level could be a model for similar efforts beyond Canada.

Do pathogen spillover, pesticide use, or habitat loss explain recent North American bumblebee declines?

Abstract: Several North American bumblebee species have recently undergone dramatic declines. The use of managed, pathogen-carrying bumblebees for pollination of greenhouse crops began shortly before these declines, and wild bumblebees near greenhouses now have high pathogen loads. This has led to speculation that pathogen spillover from commercial bumblebees caused declines of these species. We test this hypothesis using a large dataset of bumblebee occurrence records and agricultural census data. We find support for the pathogen spillover hypothesis for two species but no evidence that pathogen spillover caused the near disappearance of the previously widespread Bombus affinis. Furthermore, we show that pesticide use and habitat loss are unlikely to be major causes of decline for any of the Bombus species examined. Collectively, our analyses underscore that there remains an urgent need to identify causes of pollinator population losses.

Reconciling topographic and climatic effects on widespread and range‐restricted species richness

Abstract: Aim To identify the reasons behind differing geographical species richness patterns of range-restricted and widespread species. Location The Western Hemisphere. Methods We used regression to determine the strongest environmental predictors of richness for widespread and range-restricted mammal species in 10,000 km 2 quadrats in the continental Americas. We then used range-placement models to predict the expected correlation between range-restricted and widespread species richness were they to be determined by identical, random, or contrasting environmental factors. Finally, to determine the reasons underlying deviations from these predictions, we divided the Americas into 5% quantiles based on temperature and topographic heterogeneity and correlated richness of these two assemblages across quantiles – an approach that avoids constraints on statistical testing imposed by low potential for range overlap among range-restricted species. Results Minimum annual temperature was the strongest predictor of widespread species richness while topographic heterogeneity was the best, although weak, predictor of range-restricted species richness in conventional regression analysis. Our models revealed that the observed correlation between range-restricted and widespread species richness was similar to what would be observed if both rangerestricted and widespread species richness were determined by temperature. Patterns of range-restricted and widespread species richness were highly correlated across temperature quantiles, but range-restricted species uniquely showed an increasing pattern across heterogeneity quantiles. Main conclusions Species richness gradients among range-restricted species differ from those of widespread species, but not as extensively or for the reasons reported previously. Instead, these assemblages appear to share some but not all underlying environmental determinants of species richness. Our new approach to examining species richness patterns reveals that range-restricted and widespread species richnesses share a common response to temperature that conventional analyses have not previously revealed. However, topographic heterogeneity has assemblage-specific effects on range-restricted species.

Response to Stevens and Jenkins’ pesticide impacts on bumblebees: a missing piece

Abstract: Stevens & Jenkins (2012) highlight neonicotinoids as an important potential threat to wild bumblebees. Experiments on the effects of neonicotinoids on bumblebees demonstrate negative impacts on colonies exposed in field experimental (Whitehorn et al. 2012) or lab conditions (reviewed in Blacquiere et al. 2012; Hopwood et al. 2012). Hence, neonicotinoid use may threaten wild bee populations at or near sites where these pesticides are used. We agree that better tracking of neonicotinoid input from various treatments is needed (as described by Stevens & Jenkins 2012) to assess their wildlife impacts. However, the data available indicate that neonicotinoid use does not explain broad-scale declines among the three eastern North American bumblebee species we studied (Szabo et al. 2012). This is supported by recent evidence that these species began exhibiting declines prior to the registration and widespread use of neonicotinoids in North America (Colla et al. 2012). Stevens & Jenkins (2012) correctly point out that our data exclude seed application of pesticides. However, our data do include other neonicotinoid treatments, which can lead to higher neonicotinoid residues (see Figure S1). Although none of the relationships were statistically significant, for two of the three species studied insecticide use was actually positively related to population persistence. As noted by Stevens & Jenkins (2012), most corn seed planted in North America is treated with neonicotinoids. In the region we considered, corn is a commonly produced crop (USDA 2011). To examine the potential role of corn treatment in declines, we carried out a new analysis testing for relationships between declines and corn production density. If neonicotinoid corn treatment was a significant cause of decline, species studied should persist to a greater extent in areas with little corn production. Yet, there are no significant relationships in the direction

Pharmaceuticals and personal care products in the environment: what are the big questions?

Abstract: Background: Over the past 10–15 years, a substantial amount of work has been done by the scientific, regulatory, and business communities to elucidate the effects and risks of pharmaceuticals and p...

Pharmaceuticals in the environment--Global occurrences and perspectives.

Abstract: Pharmaceuticals are known to occur widely in the environment of industrialized countries. In developing countries, more monitoring results have recently become available, but a concise picture of measured environmental concentrations (MECs) is still elusive. Through a comprehensive literature review of 1016 original publications and 150 review articles, the authors collected MECs for human and veterinary pharmaceutical substances reported worldwide in surface water, groundwater, tap/drinking water, manure, soil, and other environmental matrices in a comprehensive database. Due to the heterogeneity of the data sources, a simplified data quality assessment was conducted. The database reveals that pharmaceuticals or their transformation products have been detected in the environment of 71 countries covering all continents. These countries were then grouped into the 5 regions recognized by the United Nations (UN). In total, 631 different pharmaceutical substances were found at MECs above the detection limit of the respective analytical methods employed, revealing distinct regional patterns. Sixteen substances were detected in each of the 5 UN regions. For example, the anti-inflammatory drug diclofenac has been detected in environmental matrices in 50 countries, and concentrations found in several locations exceeded predicted no-effect concentrations. Urban wastewater seems to be the dominant emission pathway for pharmaceuticals globally, although emissions from industrial production, hospitals, agriculture, and aquaculture are important locally. The authors conclude that pharmaceuticals are a global challenge calling for multistakeholder approaches to prevent, reduce, and manage their entry into and presence in the environment, such as those being discussed under the Strategic Approach to International Chemicals Management, a UN Environment Program.