Biological Inventories and Assessments

Toronto and Region Conservation Authority (TRCA) collects scientific data on breeding birds, breeding frogs and toads, and plants as well as vegetation communities across our jurisdiction.

The location of inventory sites changes annually based on land planning and management priorities, as well as funding.

VIEW BIOLOGICAL INVENTORY REPORTS & ASSESSMENTS

What Do We Inventory?

BREEDING BIRD SPECIES

TRCA surveys for 161 native bird species during breeding season when conducting biological inventories, including 90 Regional Species of Conservation Concern.

Breeding bird territories of species of conservation concern are mapped, and a full list of breeding bird species is created for each inventory site. SEE FULL LIST.

FROG AND TOAD SPECIES

TRCA surveys for 10 native frog and toad species when conducting biological inventories, including eight Regional Species of Conservation Concern.

Surveys begin in early spring by listening for the distinct breeding calls of each frog species in wetland habitats. Breeding frogs and toad species of conservation concern are mapped, and a full list of species is created for each site. SEE FULL LIST.

PLANT SPECIES

TRCA surveys for 951 native plant species when conducting biological inventories, including 572 Regional Species of Conservation Concern.

Flora species of conservation concern are mapped in regional forests, wetlands, and meadows, and a full species list is created for each site. SEE FULL LIST.

VEGETATION COMMUNITIES

TRCA surveys for more than 414 vegetation community types when conducting biological inventories, including 214 Communities of Conservation Concern.

trilliums bloom in a forest in Scarborough

Vegetation community boundaries are drawn on field maps, following the Ecological Land
Classification for Southern Ontario (ELC) protocol. The dominant species are documented, along with the level of disturbance (such as invasive species) that may be present. SEE FULL LIST.

Note: During site inventories, all incidental observations of mammals (including bats), reptiles (turtles and snakes), and amphibians (salamanders) are noted. These observations are appended to the site fauna species list at the end of the field season.

What Is the Data Telling Us?

Based on TRCA’s terrestrial biological inventory data, the lands in this region are home to approximately 225 native wildlife and 951 plant species. We estimate up to 10 native wildlife and 95 plant species have disappeared entirely from the region.

Most Regional Species of Conservation Concern are found only in the northern, rural portions of our watersheds where there are large amounts of natural cover.

Urbanization causes or accelerates many threats to biodiversity, including:

  • Disturbance from off-leash dogs and free-roaming cats
  • Habitat loss (e.g., new developments)
  • Invasion by non-native species (e.g., through the dumping of yard waste and informal and formal trails)
  • Pollution (e.g., excessive use of de-icing salt on trails)

It is apparent that the continual loss of natural cover and the predicted impacts of climate change in urbanizing areas will increase the loss of biodiversity occurring region-wide.

View Terrestrial Monitoring
Biological Inventories & Assessments

Click to Open Library

Contact Us

Questions? For more information, please contact:
TRCA Watershed Planning and Ecosystem Science | wpes@trca.ca