D3143: Determining the migrational patterns of North American hoverflies (Diptera: Syrphidae) through stable isotope analysis

Monday, November 11, 2024

9:00 AM – 5:00 PM MST

Location: Phoenix Convention Center, Exhibit Hall 6, PCC

Presenting Author(s)

TF

Tessa Fortnum

University of Western Ontario
London, Ontario, Canada

Co-Author(s)

JK

Jackson Kusack

University of Western Ontario
London, Ontario, Canada
KH

Keith Hobson

University of Western Ontario
London, Ontario, Canada

Syrphidae are globally essential pollinators and pest managers, yet their life history is largely unexamined. There is evidence for mass Palearctic Syrphid migration but little has been done to study Nearctic migration. Conventional tracking methods are unsuitable for Syrphidae due to their small size, but stable hydrogen isotopes offer a reliable alternative for studying their movement. An understanding of syrphid movement patterns, whether resident, migratory, or partially migratory, has implications in syrphid management, as well as plant conservation and agriculture. Migratory insects often move pollen long distances, increasing gene flow and genetic diversity between plant populations which is crucial for environmental sustainability and agriculture industry. Syrphidae are known to be generalist pollinators, utilising the majority of global crop species and animal-pollinated wildflowers and thus potentially having a large influence on gene flow through migration. Stable hydrogen isotope analysis of inert tissues can be used to approximate a place of origin, allowing for the determination of migratory patterns. Stable hydrogen analyses have been previously used extensively to reliably determine the migratory behaviour of lepidopterans and anisopterans, among others. We hypothesise that certain syrphid species undertake long-distance migrations, others remain local, and some exhibit partial migration, with only part of the population migrating. In addition to stable hydrogen isotopes, morphological measurements have been compared intra- and interspecifically to detect potential migratory phenotypes.