Monitoring Black Racers, The Largest Snake In Maine

ArrayMay 17, 2017 at 10:47 am

[caption id="attachment_2341" align="alignright" width="1024"] Black racers are Maine's largest snakes. IFW biologists are tracking this endangered species to learn more about their numbers and needs (IFW Photo by Derek Yorks)[/caption] By IFW Wildlife Biologist Brad Zitzke Nearly anyone who has spent any time in the woods or fields in their lifetimes has had the eye-opening experience of startling a snake underfoot. This can be particularly shocking if it happens in a part of the country where venomous species dwell. Thankfully, in Maine, we don’t have to worry about that as none of our nine native snake species are poisonous. Despite this, snakes have been dramatically misunderstood, and even victimized, as people have killed them out of fear for centuries. But snakes persevere in nearly every environment, filling important ecological roles by reducing levels of rodents while also preying on insects, reptiles, and amphibians, and serving as a food source for predatory birds and mammals. Racers (Coluber constrictus) exist throughout much of North America, but it is the northern black racer subspecies (C. c. constrictus) we fortunate few get to observe in Maine. Black racers are the longest snake in Maine, growing up to five feet in length. As the name suggests, they are black and sleek as adults with a white chin and gray belly. Juveniles, up to around two feet in length, typically have small black or brown spot patterns on the upper back side of their bodies. While fairly common in parts of its range throughout the eastern U.S., black racer is at the northern extent of its range in Maine and at risk of extirpation due to rarity, habitat loss, and habitat fragmentation. Black racers in Maine prefer a mix of predominantly early successional/young forest and sparsely vegetated communities – a habitat type that is generally lacking on the Maine landscape. Currently, black racers are thought to occupy around 28 locations with nine of those locations confirmed in the last five years. The species was listed as state Endangered in 1986 and is currently identified as a Priority 1 Species of Greatest Conservation Need in Maine’s Wildlife Action Plan drafted in 2015. From 2007 to 2010, Maine Department of Inland Fisheries & Wildlife biologists conducted a study on black racer habitat use and movement ecology at the Wells Barrens, home of the largest known population of black racers in the state. Much was learned from this study while monitoring 14 radio-tagged individuals. For instance, home range size was on average 79.1 hectares (195 acres!) compared to 14.7 hectares (36 acres) in a similar study in New Hampshire. We also learned more about habitat selection of black racers in Maine, indicating a strong preference for shrubland habitat, while the tagged animals still used habitats ranging from bare ground for nesting females to mature forest for refuge during hot summer days. Piecing this information together helps wildlife biologists plan for the conservation of this species. In 2016, wildlife biologists used this biological information, as well as a multitude of credible reports accumulated throughout the years at other locations in southern and southwestern Maine, as the foundation for a monitoring study to better understand the distribution of black racers. The project will continue to survey historical and known locations and adapt a monitoring program for the previously studied Wells Barrens racers. This information will help identify priority conservation areas for this rare and intriguing species. So, the next time you’re out and about and see a snake, try to get past the initial surprise of seeing a slithering relic of our past, and take a closer look. You just might learn something new and help add to our knowledge of these fascinating species. For more information or to report a sighting of a northern black racer, please contact Phillip deMaynadier ( or call 207-941-4239) or Derek Yorks ( or call 207-941-4475). [caption id="attachment_2342" align="aligncenter" width="1024"] IFW Wildlife Biologist Derek Yorks searches for black racers in the Waterboro Barrens.[/caption]