The Mottled duskywing butterfly (Erynnis martialis) is an endangered butterfly species in Canada whose range is limited to its host plants which occupy oak savanna and tallgrass prairie habitats, both globally endangered ecosystems.  The rate of decline and viability of remaining Mottled duskywing populations are currently unknown due to limited demographic and habitat distribution data. 

Since 2019, Ryan Norris and his graduate students have been collaborating with Natural Resource Solutions Inc. (Jessica Linton), Cambridge Butterfly Conservatory, Alderville Black Oak Savanna, Wildlife Preservation Canada and the Ontario Butterfly Species at Risk Recovery Team to better understand the ecology and behaviour of this species and to re-introduce it into formerly occupied and newly created habitats. Mark re-sighting surveys of remaining populations provide important information about Mottled duskywing population dynamics. In 2021, reintroduction efforts began in Pinery Provincial Park (Ontario), a site where Mottled Duskywing were last seen in the early 1990’s and, in 2024, Mottled duskywing were reintroduced to restored habitats in Norfolk County, close to the north shore of Lake Erie. 

A 2024 documentary that tells the story about our reintroduction of Mottled Duskywing to Pinery Provincial Park. Produced by Pinegrove Productions and narrated by Sarah Harmer.

*scroll past publications for additional photos of our Mottled Duskywing research

Mottled Duskywing Publications

5. Polley, M**, Linton, JE, Brewster, A, MacKenzie, AS, Keyghobadi, N, Steiner, J, Kerekes, T & Norris, DR. Host plant patch size selection of an endangered butterfly, the Mottled Duskywing (Erynnis martialis), at a reintroduction size. In review: Journal of Insect Conservation

4. Polley, M, Linton, JE, Brewster, A, MacKenzie, AS, Keyghobadi, N, Steiner, J, Kerekes, T & Norris, DR. Reintroduction of an endangered butterfly, the Mottled Duskywing (Erynnis martialis). In revision: Animal Conservation

3. Demarse, A, Trendos, E, Linton, JE, Flockhart, DTT, Brewster, A, Keyghobadi, N, Custode, L & Norris, DR. 2023. Phenology, population size, and factors influencing variation in density of an endangered butterfly, the Mottled Duskywing (Erynnis martialis). Endangered Species Research 50:195-208.

2. Henault, J, Linton, JE, Norris, DR & Westwood, R. 2022. Egg laying behavior and larval-shelter-construction of the endangered Mottled Duskwing (Erynnis martialis). Journal of the Lepidopterists’ Society 76(1):43-55.

1. Kroeze, S, Brewster, A, Linton, JE, Norris, DR, Otis, G, Young, Y & Keyghobadi, N. 2022. Microsatellites for the at-risk Mottled Duskywing butterfly, Erynnis martialis. Conservation Genetics Resources 1:1.

Photos of Mottled Duskywing Research