Kathryn Lindsay

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

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 countrys 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. Generación de Preguntas de Investigación Prioritarias para Informar a las Políticas y Gestión de la Conservación a Nivel Nacional

Relative effects of landscape-scale wetland amount and landscape matrix quality on wetland vertebrates: A meta-analysis

Conservation management of wetland-dependent species generally focuses on preserving or increasing wetland habitat. However, the quality of the landscape matrix (the intervening non-wetland portion of the landscape) has been shown to be more important than wetland availability for some wetland-dependent species. We used meta-analysis to compare the effects of wetland amount (measured as the area of wetland habitat in a landscape) and matrix quality (measured as the area of forest cover in the same landscape) on the population abundance of wetland-dependent vertebrates. We combined data across 63 studies conducted in forested ecoregions worldwide and extracted 330 population responses for 155 species, at the spatial scale that best predicted the effects of wetland. amount and forest amount for each response. In addition, to ensure that our results were not biased by the scale selected, we assessed whether the relative effects of wetland and forest amount were scale dependent. We found that the amount of wetland in a landscape had a larger effect than the amount of forest on the abundance of mammals and birds whereas, surprisingly, for amphibians the amount of forest in a landscape was more important than the amount of wetland. For reptiles, both wetland amount and forest amount showed only weak,effects on abundance. These results were not scale dependent, i.e., they were consistent across spatial scales. Our results suggest that the population distribution of wetland-dependent amphibians is more strongly related to landscape matrix quality than to wetland availability in a landscape, likely due to their requirement for access to terrestrial resources. We conclude that conservation policies for wetland biodiversity that focus only on wetland habitat will be ineffective in conserving many of these species. In addition, population viability analyses based only on wetland amount may overestimate the capacity of a landscape to support populations of wetland-dependent species.

Farmland Heterogeneity Benefits Birds in American Mid-west Watersheds

Abstract It is now well known that biodiversity in agricultural landscapes can be increased by converting production lands (i.e., farmland) into more natural habitat. However, it remains relatively unknown to what extent biodiversity can also be enhanced by changing the composition and configuration of farmland per se. We examined relationships between farmland structure and avian biodiversity in six watersheds representing a gradient in rowcrop intensity in the American Mid-west. We used canonical correspondence analysis (CCA) to model relationships at the site (0.8 ha), field (21 ha), section (165 ha) and watershed (4000–18,000 ha) extents to explore these questions: (1) At what spatial extent do birds respond most strongly to farmland structure? (2) Which farmland variables are most important? (3) Does avian biodiversity increase with increasing farmland heterogeneity? Most variation in bird assemblages was explained at the field versus the site or section extents. Of the top 20 field-extent variables in CCA, most important were: % woodland, an index of compositional heterogeneity (the modified Simpsons evenness index, MSIEI), % rowcrop, % core pasture (i.e., away from an edge), and edge density. Eighteen species were associated with woodland; their richness increased with woodland from 0% to 10%. Nine species were associated with rowcrop; their richness decreased two-fold with a change in rowcrop from 80% to 3%. Twelve species were associated with farmland heterogeneity; their richness increased four-fold with more field cover heterogeneity (MSIEI) and decreased three-fold with increasing mean field size from 1.2 to 7 ha. Field-extent &agr; and &bgr; species richness were significantly higher than expected in the null model in the two most heterogeneous watersheds and lower in the two most intensely farmed watersheds. Differences among watersheds were significant and evident in the CCA ordination plot. Our results show empirically that policies to influence farmland heterogeneity could provide a conservation benefit to avian biodiversity.

Risk of Agricultural Practices and Habitat Change to Farmland Birds

Many common bird species have declined as a result of agricultural intensification and this could be mitigated by organic farming. We paired sites for habitat and geographical location on organic and nonorganic farms in Ontario, Canada to test a priori predictions of effects on birds overall, 9 guilds and 22 species in relation to candidate models for farming practices (13 variables), local habitat features (12 variables), or habitat features that influence susceptibility to predation. We found that: (1) Overall bird abundance, but not richness, was significantly (p < 0.05) higher on organic sites (mean 43.1 individuals per site) than nonorganic sites (35.8 individuals per site). Significantly more species of birds were observed for five guilds, including primary grassland birds, on organic vs. nonorganic sites. No guild had higher richness or abundance on nonorganic farms; (2) Farming practice models were the best (∆AIC < 4) for abundance of birds overall, primary grassland bird richness, sallier aerial insectivore richness and abundance, and abundance of ground nesters; (3) Habitat models were the best for overall richness, Neotropical migrant abundance, richness and abundance of Ontario-USA-Mexico (short-distance) migrants and resident richness; (4) Predation models were the best for richness of secondary grassland birds and ground feeders; (5) A combination of variables from the model types were best for richness or abundance overall, 13 of 18 guilds (richness and abundance) and 16 of 22 species analyzed. Five of 10 farming practice variables (including herbicide use, organic farm type) and 9 of 13 habitat variables (including hedgerow length, proportion of hay) were significant in best models. Risk modeling indicated that herbicide use could decrease primary grassland birds by one species (35% decline from 3.4 to 2.3 species) per site. Organic farming could benefit species of conservation concern by 49% (an increase from 7.6 to 11.4 grassland birds). An addition of 63 m of hedgerow could increase abundance and richness of short distance migrants by 50% (3.0 to 4.8 and 1.3 to 2.0, respectively). Increasing the proportion of hay on nonorganic farms to 50% could increase abundance of primary grassland bird by 40% (6.7 to 9.4). Our results provide support for alternative farmland designs and agricultural management systems that could enhance select bird species in farmland. RESUME. De nombreuses especes d’oiseaux ont decline en raison de l’intensification des pratiques agricoles, mais ces declins pourraient etre attenues grâce a l’agriculture biologique. Nous avons apparie des sites (habitat et situation geographique) sur des fermes biologiques et des fermes non biologiques en Ontario, Canada, afin de tester des previsions a priori d’effets sur l’avifaune dans son ensemble, 9 guildes et 22 especes d’oiseaux, en relation avec des modeles candidats testant les pratiques agricoles (13 variables), les caracteristiques locales de l’habitat (12 variables) ou les caracteristiques de l’habitat qui influencent le risque de predation. Nous avons trouve que : 1) l’abondance totale d’oiseaux, mais pas la richesse, etait significativement plus elevee (p < 0,05) aux sites biologiques (moyenne de 43,1 individus par site) qu’aux Aquila Conservation & Environment Consulting, Environment Canada, Ontario Ministry of Natural Resources Avian Conservation and Ecology 6(1): 5 http://www.ace-eco.org/vol6/iss1/art5/ sites non biologiques (moyenne de 35,8 individus par site). Un nombre significativement plus eleve d’especes d’oiseaux ont ete observees chez cinq guildes, dont celle des oiseaux specialistes des prairies, aux sites biologiques. Aucune guilde n’a presente une plus grande richesse ou abondance sur les fermes non biologiques; 2) les modeles prenant en compte les pratiques agricoles etaient les meilleurs (∆AIC < 4) pour prevoir l’abondance totale d’oiseaux, la richesse des oiseaux specialistes des prairies, la richesse et l’abondance des insectivores aeriens qui chassent a l’affut et l’abondance des oiseaux nichant au sol; 3) les modeles prenant en compte l’habitat etaient les meilleurs pour prevoir la richesse dans l’ensemble, l’abondance des migrateurs neotropicaux, la richesse et l’abondance des migrateurs de courte distance (Ontario-E.-U.-Mexique) et la richesse des residents; 4) les modeles prenant en compte la predation etaient les meilleurs pour prevoir la richesse des oiseaux generalistes des prairies et des oiseaux se nourrissant au sol; 5) une combinaison de variables issues des modeles-types representait la meilleure option pour prevoir la richesse ou l’abondance dans leur ensemble, chez 13 des 18 guildes (richesse et abondance) et 16 des 22 guildes examinees. Cinq des dix variables decrivant les pratiques agricoles (y compris l’utilisation d’herbicides et le type de fermes biologiques) et 9 des 13 variables touchant l’habitat (y compris la longueur des haies et la proportion de foin) etaient significatives dans les meilleurs modeles. La modelisation du risque a indique que l’utilisation d’herbicides pouvait toucher les oiseaux specialistes des prairies, a raison d’une espece (declin de 35 %, de 3,4 a 2,3 especes) par site. L’agriculture biologique pourrait favoriser les especes dont la conservation est preoccupante, jusqu’a 49 % (augmentation de 7,6 a 11,4 oiseaux de prairie). Un ajout de 63 m de haie permettrait d’augmenter l’abondance et la richesse des migrateurs de courte distance de 50 % (de 3,0 a 4,8 et de 1,3 a 2,0, respectivement). Une hausse de 50 % de la proportion de foin sur les fermes non biologiques permettrait d’augmenter de 40 % l’abondance des oiseaux specialistes des prairies (de 6,7 a 9,4). D’apres nos resultats, une attention particuliere portee a la configuration des fermes et a la gestion agricole permettrait d’ameliorer le sort d’especes d’oiseaux selectionnees dans les paysages agricoles.

Relative Importance of Nesting Habitat and Measures of Connectivity in Predicting the Occurrence of a Forest Songbird in Fragmented Landscapes

Theoretical and empirical studies suggest that well-connected networks of forest habitat facilitate animal movement and contribute to species’ persistence and thereby the maintenance of biodiversity. Many structural and functional connectivity metrics have been proposed, e.g., distance to nearest neighboring patch or graph-based measures, but the relative importance of these measures in contrast to nesting habitat at fine spatial scales is not well established. With graph-based measures of connectivity, Euclidean distances between forest patches can be directly related to the preferred gap crossing distances of a bird (functional connectivity). We determined the relative predictive power of nesting habitat, forest cover, and structural or functional connectivity measures in describing the breeding distribution of Hooded Warblers (Setophaga citrina) over two successive breeding seasons in a region highly fragmented by agriculture in southern Ontario. Logistic regression models of nesting occurrence patterns were compared using Akaike’s information criterion and relative effect sizes were compared using odds ratios. Our results provide support for the expectation that nest-site characteristics are indeed related to the breeding distribution of S. citrina. However, models based on nesting habitat alone were 4.7 times less likely than a model including functional connectivity as a predictor for the breeding distribution of S. citrina. Models of nest occurrence in relation to surrounding forest cover had lower model likelihoods than models that included graph-based functional connectivity, but these measures were highly confounded. Graph-based measures of connectivity explained more variation in nest occurrence than structural measures of forest connectivity, in both 2004 and 2005. These results suggest that S. citrina selected nesting areas that were functionally connected at their preferred gap crossing distances, but nesting habitat was a critically important predictor of nest occurrence patterns. RESUME. Des recherches theoriques et empiriques laissent supposer que des reseaux de milieux forestiers bien connectes permettent le deplacement de la faune et contribuent a la perennite d’une espece et, par le fait meme, au maintien de la biodiversite. De nombreuses mesures de connectivite structurelle et fonctionnelle ont ete avancees, par exemple la distance a l’ilot voisin le plus proche ou encore, des mesures fondees sur des graphiques, mais l’importance relative de ces indices comparativement a l’habitat de nidification a des echelles spatiales fines n’est pas etablie clairement. A partir de mesures de la connectivite fondees sur des graphiques, la distance euclidienne entre les ilots forestiers peut etre directement reliee a la distance preferee de traversee d’une trouee par un oiseau (connectivite fonctionnelle). Nous avons determine la capacite predictive relative de l’habitat de nidification, du couvert forestier et des mesures de connectivite structurelle et fonctionnelle pour decrire la repartition de nidification de la Paruline a capuchon (Setophaga citrina) au cours de deux saisons de nidification successives dans une region tres fragmentee par l’agriculture, dans le sud de l’Ontario. Des modeles de regression logistique des tendances dans l’occurrence de nidification ont ete compares au moyen du critere d’information d’Akaike, et l’amplitude des effets relatifs a ete evaluee a l’aide du risque relatif approche (odds ratio en anglais). Nos resultats corroborent les suppositions selon lesquelles les caracteristiques du site de nidification sont vraiment reliees a la repartition de nidification de S. citrina. Toutefois, les modeles fondes sur l’habitat de nidification uniquement etaient 4,7 fois moins performants qu’un modele qui comportait la connectivite fonctionnelle comme variable predictive de la repartition de nidification de S. citrina. Les modeles fondes sur l’occurrence des nids en fonction du couvert forestier environnant etaient moins vraisemblables que les modeles qui incluaient la connectivite University of Toronto, Department of Ecology and Evolutionary Biology, University of Toronto, Ontario Program Manager Bird Studies Canada c/o Environment Canada, Wildlife and Landscape Science Directorate,