Natural Heritage Methodology

The Natural Heritage Information Centre adheres to the Natural Heritage Methodology. These standard methods were developed by the international NatureServe network of conservation data centres. The NHIC is a member of NatureServe.

The standards help NHIC provide authoritative scientific information about Ontario’s natural heritage to scientists, policy makers, planners and the public.

Learn more: NatureServe’s Natural Heritage Methodology

Natural Heritage Methodology describes:

  • what species, wildlife concentration areas, or plant communities exist in a particular area
  • how these species, wildlife concentration areas, or plant communities are doing

Key components include:

  • methods to complete field inventories
  • methods to estimate the likelihood a species, wildlife concentration area or plant community will go extinct or be eliminated (conservation status ranks)
  • methods to review and record observation records
  • methods to create element occurrences, which are areas of land or water on or in which a species or plant community is or was present. They are important to the conservation of a species or plant community.

Conservation Status Ranks

Conservation status ranks estimate a species’ risk of going extinct or being extirpated. They can also rank a plant community’s risk of elimination. They help identify priorities for inventory, protection and management.

The NHIC and the NatureServe network have developed standard methods to evaluate species and plant communities and assign conservation status ranks.

  • Global Rank (GRank) is the conservation status of a species or plant community across its entire range.
  • National Rank (NRank) is the conservation status of a species or plant community within a particular country.
  • Subnational Rank (SRank) is the conservation status of a species or plant community within a particular province, territory or state.

NHIC assigns subnational ranks (SRanks) for species and plant communities in Ontario using the best available information and considering factors such as abundance, distribution, population trends and threats.

Conservation status ranks do not have any legal standing in Ontario. They are independent of status designated under Canada’s Species at Risk Act and Ontario’s Endangered Species Act.

Learn more: conservation status ranks

How the NHIC maps observations

The NHIC maps observations as polygons based on:

  • coordinates (latitude/longitude or easting/northing) of the location of the observation
  • description of how the observer derived the coordinates
  • description or maps of the location provided by the observer

How the NHIC generates element occurrences

An element occurrence is an area of land and/or water where a species or plant community is or was present. They represent areas important to the conservation of a species or plant community such as the courtship, nesting, rearing and feeding areas of a bird. The NHIC generates each element occurrence from one or more observations.

The NHIC follows international standard element occurrence specifications, developed by the NatureServe network, to combine observations to form element occurrences.

The specifications define what does and does not constitute an element occurrence. For example, for a bald eagle, the NHIC considers a record for a nesting site an element occurrence or part of an element occurrence. But it does not consider a record of a migrating bald eagle an element occurrence or part of an element occurrence.

Element occurrence specifications also show which features, like busy roads and dams, prevent a species from moving or dispersing. This information defines the boundaries of an element occurrence. The specifications also define how far apart observations that are part of the same element occurrence can be.

Some specifications are species specific and others apply to a group of species (e.g., ducks and geese, sticklebacks, or freshwater mussels).

Learn more: element occurrence specifications (search by species)