The law

Ontario’s Endangered Species Act protects endangered or threatened species — including fish and mussels that are in decline and disappearing from the province.

You need to follow certain rules if you are working in or around waterways (e.g. rivers, creeks, streams) that are habitat for these species.

The rules apply if you are maintaining, repairing, expanding, removing or replacing a:

  • bridge
  • culvert
  • pier
  • pipeline
  • conduit
  • some other structures

In some cases, the rules also apply to constructing new pipelines and conduits.

Source law

This is a summary of the provincial laws. You can find a complete set of provincial rules related to this activity in:

  • Endangered Species Act, 2007
  • Ontario Regulation 242/08 (general)

The rules

You must:

  • register the activity and the affected species with the Ministry of Natural Resources and Forestry (before work begins)
  • take steps to minimize effects to the species and habitat
  • provide a benefit to the species (e.g. plant native vegetation to improve water quality)
  • create and implement a mitigation plan
  • monitor the effectiveness of the steps you take to minimize effects on — and provide benefit to — the species
  • create and maintain a monitoring record
  • report sightings of rare species (and update registration documents, if needed)

Report a species

If you see or encounter a species, you must inform the Natural Heritage Information Centre — within 3 months of a sighting or encounter.

To report a sighting:

  • fill out a Rare Species Reporting form online
  • complete each section in the report
  • hit the submit button to send in the report

Report a rare species

Contact the Natural Heritage Information Centre

Types of species

The rules apply to these species:


  • Eastern Pondmussel
  • Fawnsfoot
  • Hickorynut
  • Kidneyshell
  • Lilliput
  • Mapleleaf Mussel
  • Rayed Bean
  • Round Pigtoe
  • Salamander Mussel
  • Snuffbox
  • Threehorn Wartyback
  • Wavy-rayed Lampmussel


  • Eastern Sand Darter
  • Pugnose Shiner
  • Redside Dace
  • Black Redhorse
  • Channel Darter
  • Cutlip Minnow
  • Silver Shiner
  • Spotted Gar
  • Warmouth

How to register

Step 1: Download the Natural Resources Registration Guide

  • print a copy or
  • open the guide in a new window or tab

Natural Resources Registration Guide

Step 2: Create a ONe-key ID and Natural Resources client profile

You need a ONe-key ID and a Natural Resources client profile to register online. ONe-key is a secure account that gives you online access to Ontario government programs and services.

Once you have a ONe-key ID, you will be asked to create either an individual or business profile for Natural Resources registrations. Create:

  • business profile to register business activities if you are a(n):
    • business
    • non-profit organization
    • municipality
    • government agency
    • ministry
    • authorized representative registering activities on behalf of any of the above.
  • an individual profile to register non-business activities

Open a new window or tab to:

Create a business profile
Create an individual profile

If you already have a ONe-key ID:

  • sign in to ONe-key
  • confirm your Natural Resources profile

Open a new window or tab to:

Sign in as a returning business
Sign in as a returning individual

Step 3: Register an activity

  • select My Services from the main menu
    • if you are an authorized representative, identify the business you are representing
  • click on Create New Registration
  • select Notice of Activity and Other Notices under the Endangered Species Act (ESA) from the registry options
  • selectAquatic Species - Activities in the habitat of certain fish or mussels
  • register the activity
  • submit the registration

Step 4: Receive confirmation

  • receive an official Confirmation of Registration by email
    • By law, the regulation requires you to keep contact information up-to-date should the Ministry need to contact you
    • By law, the regulation requires you to submit requested documents within 14 days of a request from the Ministry using the contact information you provide
  • keep a copy as proof of registration
  • registration is free

If you need assistance to register your activity, please call 1-800-387-7011.

If you can't apply online:

  • download the registration form and user guide
  • print, complete and mail the form
  • wait for confirmation

Notice of Activity Form - Aquatic Species Activities in the habitat of certain fish or mussels

When you need a permit

You could still need a permit if work:

  • is of a certain size or magnitude or effect
  • could change the path the water flows (alignment)
  • uses materials to build a temporary access road, bridge or culvert
  • is related to a dam or hydroelectric-generating station
  • affects certain endangered or threatened species
  • is happening in:
    • The Detroit River
    • The Niagara River
    • The St. Clair River
    • The St. Lawrence River
    • some portions of the Sydenham River or Ausable River

To apply for a permit, contact a local Ministry of Natural Resources and Forestry office.

Find an MNRF district office

Minimize effects on a species

You must:

  • avoid work during reproduction and rearing seasons
  • prevent a species from entering the work area (e.g. install a coffer dam)
  • relocate mussels following federal government standards
  • keep machinery and vehicles out of the water
  • maintain the flow and quality of water
  • minimize sediment and erosion
  • keep the bottom of culverts open
  • use equipment in a way that minimizes the impact on habitat
  • restore damage to shorelines (e.g. plant native vegetation)
  • follow special rules for pipelines and culverts (e.g. no damage to waterbeds or banks)
  • adjust steps you're taking, if they're not working

Benefits to the species

You must enhance the habitat beyond the immediate work area.

To do this, you need to do at least 1 of these activities:

  • restore an area of shoreline habitat (called the "riparian" habitat) that is:
    • already degraded and
    • at least twice the size of the area affected by your work
  • plant native vegetation around stormwater-management ponds to improve water quality and reduce water temperature:
  • in areas where there’s not enough vegetation around the pond and
  • in an area at least twice the size of the one affected by your work
  • install certain mechanisms (e.g. a cooling trench) to improve stormwater management and reduce the water temperature
  • remove barriers so that fish can move through waterways (e.g. a perched culvert)

You need to finish these activities within 1 year of completing work to structures.


Some work to culverts (e.g. replacing a closed-bottom culvert with either an open-bottomed one or a clear-span bridge) can help fish and mussel habitats.

Doing this replacement work means that you do not need to complete an action listed above.

Mitigation plans

Mitigation plans must include the best available information on a species.

You can get this information from:

  • The Ministry of Natural Resources and Forestry
  • Aboriginal traditional knowledge
  • community knowledge (e.g. local nature clubs)

A plan must:

  • be prepared by an expert on the species (before work begins)
  • describe the work, including:
    • how it will affect species and its habitat
    • a timeline for all stages of the work (with start and end dates)
  • include a map with:
    • the location of the work and
    • all waterways in the area
  • describe how you determined the species was affected (e.g. surveys, records)
  • say how you will minimize effects on species
  • describe what actions you will take to benefit the species
  • describe the state of the area before you provided a benefit to the species (e.g. how degraded it was before you improved it)
  • outline how you plan to monitor

You must keep the plan for 5 years after work ends — and give a copy to the Ministry of Natural Resources and Forestry within 14 days, if asked.


You must monitor how effective you are when it comes to:

  • minimizing affects to species
  • providing benefits to species

This includes collecting information and data about:

  • the work site while work is happening (daily)
  • the area where you are providing a benefit to the species (daily until actions end)
  • both areas for 5 years after work ends

Reporting process

You must prepare and maintain a record that:

  • describes the steps you took to minimize effects on the species
  • describes the steps you took to benefit the species
  • evaluates how effective these steps and actions were
  • provides data and information collected during monitoring
  • details any encounters with the species

You must keep your record for 5 years after work ends — and give a copy to the Ministry of Natural Resources, if asked.

Identify a species at risk

If you are unsure about a certain species — and would like help identifying or confirming what it is — you can see photos and get more information on the Endangered Species website.

Get more details about a species