Ottoe skipper (Hesperia ottoe) COSEWIC assessment and status report: chapter 7

Few data are available on population sizes and trends at any sites where H. ottoe was previously known in Canada. In the Canadian National Collection (CNC), there are two male H. ottoe collected on July 27, 1921 and two females collected on August 12, 1926 from the “Aweme” area (CNC collection database: Manitoba Conservation, Biological and Conservation Data System data). There is also a record from Rounthwaithe, with no collection data (CNC collection database). Hesperia ottoe was not reported again in Canada until the late 1980s, when a few individuals were collected by Richard Westwood in Spruce Woods Provincial Park (Klassen et al. 1989, Westwood, pers. com. 2003). Unfortunately, these specimens could not be located. The paucity of records since its original discovery suggests that this species has always been very rare in Canada.

Hesperia ottoe was not found at any of the previously known localities during a 7-day survey in 2003 (Figure 4). In the United States, H. ottoe and H. dacotae often co-occur on mixed-grass prairie areas (Dana 1991). However, H. ottoe was not observed at any of the Canadian sites surveyed for H. dacotae during 2002 (Figure 4). It is possible that H. ottoe no longer exists in Canada. However, since the habitat in Spruce Woods Provincial Park where this skipper was last reported appears to be relatively undisturbed, it is possible that the species still exists there or in the surrounding areas. Population numbers of most skipper species appeared to be very low in Manitoba in 2003 (compared to 2002), possibly due to drought conditions that had prevailed in the region since the winter. Hesperia ottoe may not have been detected because the population numbers may have been low. More surveys are needed before it can be concluded that the species is extirpated at this site and in Canada.

Figure 4. Survey sites for Hesperia ottoe in 2002 and 2003.

Figure 4. Survey sites for Hesperia ottoe in 2002 and 2003.

Little information is available on population sizes and trends for H. ottoe in the United States. Although H. ottoe is widely distributed in the United States, it is generally highly local and generally uncommon to rare at most sites (Dana 1991, Dana, pers. com. 2004, NatureServe 2003). In North Dakota, all records for this species obtained by McCabe and Post were single individuals, and no two captures were made within 48 km of each other (McCabe and Post 1977).

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