Storeria occipitomaculata

No evidence of separate lineages has been found between the sympatric brown and grey color morphs (Grudzien and Owens 1991). No subspecies are recognized by Crother (2017).

There are two distinct dorsal color morphs, light charcoal gray and medium brown; allozyme evidence confirms that they are members of a common gene pool (Grudzien and Owens 1991).

Subspecies pahasapae is thought to intergrade with subspecies S. o. occipitomaculata over a wide area in Minnesota, southern Manitoba, and adjacent areas. However, this might represent clinal variation, and validity of the subspecies designations is open to question. Further study of variation in the northwestern part of the range of S. occipitomaculata is needed (Ernst 2002).

This species is widespread in the eastern U.S. and Canada. There are no major threats or declines reported, although the species has likely declined slightly due to urbanization and droughts.

This species is widespread through the eastern United States. and Canada. The range extends from southern Manitoba and southern Quebec, Canada south to southeastern Texas, the Gulf Coast, and central Florida. This includes isolated populations in the Black Hills of extreme eastern Wyoming and western South Dakota, and south-central Nebraska (Ernst 2002, Ernst and Ernst 2003, Cairns et al. 2018, Schaaf and Caven 2023).

This species is represented by a large number of occurrences (subpopulations) (Ernst 2002).

No major threats are known. This snake is tolerant of minor habitat alterations. Urbanization results in localized declines (Gigeroff and Blouin-Demers 2023). The increasing probability of droughts due to human-induced climate change will likely cause declines in this species by reducing activity levels and habitat suitability (Eli et al. 2015).