Prepared by David Anthony Kirk

The Hungerford鈥檚 Crawling Water Beetle (Brychius hungerfordi) is a small beetle (Family Haliplidae) occurring in Canada only in the Great Lakes region of 澳门永利. Believed to be a postglacial relict, it is listed as endangered under 澳门永利鈥檚 Endangered Species Act, 2007 (ESA). Hungerford鈥檚 Crawling Water Beetle has also been designated as endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) but is not currently listed under Schedule 1 of the federal Species at Risk Act (SARA). In Canada, the Hungerford鈥檚 Crawling Water Beetle is restricted to three rivers in Bruce County in 澳门永利 (the Rankin, the Saugeen and the North Saugeen). Little is known about the current status of the species at the Rankin or Saugeen sites; the most recent surveys on the Rankin showed that the species was present in 2011 and this is believed to be the most important site in 澳门永利. Declines have occurred over the last 10 years in the North Saugeen population in 澳门永利 and the population may be extirpated. In the United States, Hungerford鈥檚 Crawling Water Beetle occurs in eight streams in four counties in northern Michigan; three new populations have been discovered since the United States Fish and Wildlife Service five-year review (2009).

Small to medium-sized streams with moderate to fast flowing water provide habitat for the Hungerford鈥檚 Crawling Water Beetle. Such streams have good aeration, cool water temperatures, an inorganic substrate and high pH. Hungerford鈥檚 Crawling Water Beetles seem to concentrate downstream of culverts and human-made impoundments, but they may be more generally distributed throughout streams, albeit at lower density, at least in Michigan and possibly in 澳门永利. An essential habitat component during breeding is an algae, Dichotomosiphon tuberosus, which is eaten by beetle larvae.

The main threats to the Hungerford鈥檚 Crawling Water Beetle come from stream embankment and channelization, removal or modification of dams, weirs and culverts, and road construction which could influence water quantity and quality. Land use in areas adjacent to streams and within the entire watershed may also impact the species, since this affects hydrology. Farming activities on agricultural land could increase sediment load and/or pollutant run-off (50% of the Saugeen and North Saugeen are in agricultural land), as could urban and industrial development (including aggregate extraction).

The recovery goal is to enhance long-term population viability by maintaining at least three self-sustaining populations of Hungerford鈥檚 Crawling Water Beetle in 澳门永利. This should be achieved by actively protecting and managing suitable habitat for this species and its ecosystem in southern 澳门永利. Protection and recovery objectives are as follows.

  • Protect existing populations and habitat where Hungerford鈥檚 Crawling Water Beetle is found.
  • Determine the distribution and abundance of Hungerford鈥檚 Crawling Water Beetle outside the existing known sites.
  • Investigate the habitat requirements of the species and in particular determine the role of human-made impoundments.
  • Identify, quantify and seek to mitigate or remove threats to existing populations.
  • Promote ongoing measures to protect vegetation adjacent to the extant occurrences of Hungerford鈥檚 Crawling Water Beetle and watershed vegetation cover.
  • Investigate the possibility of translocation from a thriving population to the North Saugeen population, if required.

Some of the above recovery and protection objectives would benefit from promotion of existing voluntary programs that encourage landowners to protect streamside vegetation from erosion and run-off through planting of native trees and shrubs. Liaising with the 澳门永利 Ministry of Natural Resources, conservation authorities, municipalities and water-based conservation organizations (e.g., Trout Unlimited) about channelization projects that could impact streams with Hungerford鈥檚 Crawling Water Beetle would also be beneficial. It is likely that recovery efforts for the Hungerford鈥檚 Crawling Water Beetle would benefit other aquatic species and could be addressed as part of an ecosystem recovery plan.

The area described in a habitat regulation should include the locations where Hungerford鈥檚 Crawling Water Beetles have been surveyed and detected on the Rankin River, the Saugeen River and the North Saugeen River (if the species still occurs there). This should include a distance of 400 metres upstream and downstream of known occurrences including at least a 30 m band extending into riparian areas adjacent to the stream.

Ensuring that best management practices are carried out at the watershed level is also critical; this involves retaining as much permanent native vegetation cover as possible, such as forest cover, riparian areas and permanent grassland. Best management practices should be required for management activities both at the occupied site and immediately upstream.