Meet the Expert Who Inventories Our Watershed

Meet the Expert Who Inventories Our Watershed

There are 376 native plant species, 41 mammal species and 244 bird species in the Credit River Watershed. We know facts like these because of the work of CVC’s Natural Heritage Inventory (NHI) program.

CVC’s Dawn Renfrew, Senior Specialist, Natural Heritage Inventory, shares her experiences working in the most wild areas of the Credit River Watershed and tells us why natural heritage inventories matter.

CVC’s Dawn Renfrew

What is a natural heritage inventory?

An inventory is a list of things in a particular place. Natural heritage refers to natural features, like species and plant communities. So, the goal of our natural heritage inventory is to list what species and plant communities are present and how they are distributed across the Credit River Watershed.

What does CVC’s NHI team do?

From May to early October, our team treks deep into forests, kayaks into wetlands and meanders through meadows while mapping and describing plant communities.

We follow a standardized procedure, used across southern Ontario, called Ecological Land Classification (ELC) to document what we see. This makes it easier to share findings about plant communities with ecologists across southern Ontario. With this common language we can understand which plant communities are common and widespread across Ontario and which ones are rare or localized.

What’s the most challenging part of natural inventories?

Waking up early! The best time to observe birds is just after sunrise. Between June and mid-July our team is out as early as 5 a.m. We identify birds by sight and by listening to their calls.

But it’s not always early morning work. Our hours shift to the night in order to inventory bats and frogs. It’s under the cover of darkness that breeding frogs sing their hearts out for a mate and bats actively feed on insects.

We need to be out when animals are most active so they can help us fully understand their distribution.

This is a little brown bat and is a species that lives in the Credit River Watershed.

What data is collected?

Our inventories are thorough. We collect and analyze a lot of data. We:

  • Create a full list of all the plant species found in a community
  • Identify which species are the most abundant in each area we go to
  • Record species of concern
  • Determine soil types
  • Measure tree diameter (the size of the tree’s trunk)
  • Note any invasive species we see and report back to our invasive species program
  • List all wildlife we see

Sonar recording of a bat call at night.

What is the most interesting plant or animal you have found?

There are so many cool species in the Credit River Watershed, but I am picking spicebush (Lindera benzoin). It has plain green leaves with a warm, spicy aroma. Its pretty yellow flowers bloom in early spring and it has brilliant red berries in late summer and fall.

I first found a single bush while walking along a trail at Silver Creek Conservation Area. I was so excited and amazed. Since then, I’ve seen them more abundantly along the slope of the Niagara Escarpment. Spicebush is known to grow further south but the fact that it grows this far north along our portion of the Niagara Escarpment is neat to me!

The delicate flowers of the spicebush.

What does NHI work mean for the watershed?

Our boots-on-the-ground data is critical to conservation planning. Think of it this way, how could you run a store well if you didn’t know what you have on your shelves?

Our work gathers, organizes, and keeps data that many programs at CVC rely on. It’s used to:

  • Build and verify the natural heritage system
  • Identify significant wildlife habitat and map locations
  • Support climate change vulnerability models
  • Inform species of conservation concern indices
  • Add data to forest and wetland quality analyses
  • Inform invasive species tracking
  • And more!

The data and analysis are also important for our municipal partners and other government agencies. This information helps them balance development and environmental values.

Interested in learning more about NHI? Visit our natural heritage inventory page.

3 Comment
  • Maria A. says:

    What a wonderful and interesting story, thank you so much, dear Dawn! I wish that in Canada they give more promotion for these kind of jobs and professional careers and projects since elementary school, maybe with incentives like the trade jobs so more youth could fall in love and take care of our watersheds and beautiful country. I find, specially now, an urgent need to educate and involve all the community, specially since young and youth age, in the care of our ecosystems and natural areas much more, and our future will be bright and full of Hope! Even make it mandatory at the schools, after all, the safest to be is outdoors now and always. God bless and congratulations! Muchas gracias, love your smile!

  • Ilda C says:

    Thank you Dawn and the NHI Team. Your dedicated work is so important for the conservation of our Credit River Watershed, home to so many plants and wildlife. Good to know that the ELC has been established, for communities around Ontario to share in the conservation of the whole. Keep up the great work!!

  • Brenda Dolling says:

    I really appreciate your work, Dawn, and the work of your team. When we bought our farm in Caledon we had your team come and inventory the living plants and animals here. We are continually trying to make this farm a welcome place for all living things. Many thanks for the head start!

Leave a Comment

COVID-19 related service changes
Data and information released from Credit Valley Conservation (CVC) are provided on an 'AS IS' basis, without warranty of any kind, including without limitation the warranties of merchantability, fitness for a particular purpose and non-infringement.

Availability of this data and information does not constitute scientific publication. Data and/or information may contain errors or be incomplete. CVC and its employees make no representation or warranty, express or implied, including without limitation any warranties of merchantability or fitness for a particular purpose or warranties as to the identity or ownership of data or information, the quality, accuracy or completeness of data or information, or that the use of such data or information will not infringe any patent, intellectual property or proprietary rights of any party. CVC shall not be liable for any claim for any loss, harm, illness or other damage or injury arising from access to or use of data or information, including without limitation any direct, indirect, incidental, exemplary, special or consequential damages, even if advised of the possibility of such damages.

In accordance with scientific standards, appropriate acknowledgment of CVC should be made in any publications or other disclosures concerning data or information made available by CVC.