Hungerford’s crawling water beetle is likely a glacial relict — a species that survived from the ice age in an isolated habitat — found only in a few rivers in Ontario and Michigan. Small changes to their aquatic homes could have big impacts on this globally rare insect.
Despite their aquatic habitat, Hungerford’s crawling water beetles are actually clumsy swimmers, preferring to crawl when possible. The tiny beetle was first documented in Canada in 1986 and measures about four millimetres long, adding to the difficulty of locating it. Studies show that the larvae feed on an algae called Dichotomosiphon. Adults may live up to 18 months.
Hungerford’s crawling water beetles live in small and medium-sized streams that have cool, fast-flowing water. They are often found immediately downstream from beaver dams, culverts and artificial barriers.
This beetle is only found in three rivers in Ontario’s Bruce County and five rivers in northern Michigan. The number of beetles in Canada is unknown, although the population in a single pool in Michigan was estimated to have approximately 1,100 individuals.
The survival of Hungerford’s crawling water beetles is intimately tied with the streams they occupy. As such, agricultural runoff may threaten this species. Waterpower development projects, permits to take water and other projects that alter the streams’ flow, temperature and chemistry could also have an impact, while non-native fish such as brown trout may prey on the beetles.
Recommended Recovery Actions
The provincial Recovery Strategy for Hungerford’s crawling water beetle calls for a number of conservation measures, including identifying threats to existing populations, working with farmers to reduce agricultural runoff, working with landowners to steward aquatic habitat and investigating the possibility of translocating beetles.
What We Are Doing
The Hungerford’s crawling water beetle is on Wildlife Preservation Canada’s priority list for potential future action. Find out how we are currently saving other Canadian insects, such as the Taylor’s checkerspot butterfly and yellow-banded bumble bee, and how you can make a difference.