Insects represent the most diverse and functionally important group of flying migratory animals around the globe, yet their small size makes tracking even large migratory species challenging. We attached miniaturized radio transmitters (less than 300 mg) to monarch butterflies ( Danaus plexippus ) and common green darner dragonflies ( Anax junius ) and tracked their autumn migratory movements through southern Ontario, Canada and into the United States using an automated array of over 100 telemetry towers. The farthest estimated distance a monarch travelled in a single day was 143 km at a wind-assisted groundspeed of 31 km h −1 (8.7 m s −1 ) and the farthest estimated distance a green darner travelled in a single day was 122 km with a wind-assisted groundspeed of up to 77 km h −1 (21.5 m s −1 ). For both species, increased temperature and wind assistance positively influenced the pace of migration, but there was no effect of precipitation. While limitations to tracking such small animals remain, our approach and results represent a fundamental advance in understanding the natural history of insect migration and environmental factors that govern their movements.

Effective habitat restoration requires an understanding of species habitat preferences and the associated mechanisms driving those preferences. We examined the patterns and causes of oviposition preference in the monarch butterfly, a rapidly declining species, in southwestern Ontario at multiple spatial scales. Oviposition preference was dependent on both the size and density of the milkweed patch, as well as landscape type. Small (<16 m 2 ), low-density (0-2 milkweed per m 2 ) milkweed patches in agricultural landscape had the highest egg density compared to all types of milkweed patches in non-agricultural and roadside landscapes. Mediumsized patches had the highest predator abundance. Variation in the diversity of predators and parasitoids, abundance of parasitoids, and occurrence of parasites of monarch eggs and larvae did not appear to coincide with preferred egg laying habitats. Our results have important implications for restoring milkweed as an approach to counteract monarch butterflies declines. iii ACKNOWLEDGEMENTS This work was supported by Syngenta Canada Inc. and the ENGAGE and Discovery Grants from the Natural Sciences and Engineering Council. A Wildlife Scientific Collector's Authorization was obtained from the Ministry of Natural Resources (1079985) in order to collect monarchs. In addition, a research permit to conduct fieldwork on Nature Conservancy of Canada (NCC) land was obtained (AG-ON-2015-149612). I would like to thank my advisor, Ryan Norris, for his substantial guidance and support to this project, and for providing this tremendous learning opportunity. I would also like to thank my advisory committee, Gard Otis and Alex Smith, for their helpful advice and support over the last two years. Tyler Flockhart provided considerable support and advice through all stages of this project. My time during my masters was substantially enriched by the support of Norris lab mates, and WiP group members (Norris, Newman, McAdam, and Fryxell labs). I would especially like to thank my office mates, Danielle Ethier, Alex Sutton, Sam Knight, and Alana Wilcox for their friendship and unwavering support. I would like to extend my gratitude towards Brad Woodworth and Gustavo Betini who helped with analyses when all hope seemed lost. At Bird Studies Canada I would like to thank Stuart Mackenzie, Myles Falconer, and Jon McCracken for aiding with field logistics. At the Long Point Bird Observatory I would like to thank Mark Conboy, and visiting researchers and volunteers who made my time in the field enjoyable. Fieldwork was made possible by the dedication of field assistants Anjuli Dabydeen, Aaron Drost, and Matthew Macpherson. Field volunteers, Caroline Gabani and Blair Fitz-gerald, time was greatly appreciated. I would also like to thank Ellen Richards and Kaelin Carbonetto who assisted with invertebrate predator and parasitoid identification. At Syngenta, I'd like to thank Paul Hoekstra for providing agricultural field logistics, and Brian Woolley, Patricia Kloepfer, and Marijke Van Andel for field scouting a...

Survival probability is fundamental for understanding population dynamics. Methods for estimating survival probability from field data typically require marking individuals, but marking methods are not possible for arthropod species that molt their exoskeleton between life stages. We developed a novel Bayesian state-space model to estimate arthropod larval survival probability from stage-structured count data. We performed simulation studies to evaluate estimation bias due to detection probability, individual variation in stage duration, and study design (sampling frequency and sample size). Estimation of cumulative survival probability from oviposition to pupation was robust to potential sources of bias. Our simulations also provide guidance for designing field studies with minimal bias. We applied the model to the monarch butterfly (Danaus plexippus), a declining species in North America for which conservation programs are being implemented. We estimated cumulative survival from egg to pupation from monarch counts conducted at 18 field sites in three landcover types in Iowa, USA, and Ontario, Canada: road rightof-ways, natural habitats (gardens and restored meadows), and agricultural field borders. Mean predicted survival probability across all landcover types was 0.014 (95% CI: 0.004-0.024), four times lower than previously published estimates using an ad hoc estimator. Estimated survival probability ranged from 0.002 (95% CI: 7.0EÀ7 to 0.034) to 0.058 (95% CI: 0.013-0.113) at individual sites. Among landcover types, agricultural field borders in Ontario had the highest estimated survival probability (0.025 with 95% CI: 0.008-0.043) and natural areas had the lowest estimated survival probability (0.008 with 95% CI: 0.009-0.024). Monarch production was estimated as adults produced per milkweed stem by multiplying survival probabilities by eggs per milkweed at these sites. Monarch production ranged from 1.0 (standard deviation [SD] = 0.68) adult in Ontario natural areas in 2016 to 29.0 (SD = 10.42) adults in Ontario agricultural borders in 2015 per 6809 milkweed stems. Survival estimates are critical to monarch population modeling and habitat restoration efforts. Our model is a significant advance in estimating survival probability for monarch butterflies and can be readily adapted to other arthropod species with stage-structured life histories.

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