Welcome to Petrie Island’s biodiversity blog.
The Biodiversity Campaign is a project to mark the 25th Anniversary of the Friends of Petrie Island. It aims to profile the depth and breadth of biodiversity at Petrie Island and educate visitors about the key and various species on Petrie Island. Petrie Island’s unique environment of wetlands, Carolinian forest, being on a major watershed and along migratory pathways, offer an amazing richness in resident and visiting species, some of which are considered species at risk.

To post an entry in this blog, click here.

    #22- The Humans of Petrie Island

    By Laura Reinsborough, Ottawa Riverkeeper

    Though turtles and otters both have a special place in my heart, I have to say that my favourite species at Petrie are the humans.

    That’s right, homo sapiens. The humans of Petrie are very special indeed.

    There are so many humans who make Petrie the special place that it is: the Algonquin Anishnaabeg who are the original and ongoing caretakers of the land; the people who comprise Friends of Petrie Island, volunteering their time and giving their energy to bring community ideas to life; the ones who visit regularly and who have made Petrie a part of their regular routine and family traditions; the ones who have an eye for seeing the hidden wildlife and share their photos so others can see Petrie the way they see it; the ones who stand up for its protection, making sure that its ecological health remains a priority; and the ones who craft interpretive signage and programming so that every visit to Petrie can be an educational and engaging experience for me and my kids alike.

    I moved to Orleans a year ago to take on a new job with big responsibilities, as Riverkeeper & CEO with Ottawa Riverkeeper. Petrie Island – and all of its humans, whether they know it or not – have been my teachers as I come to know the Ottawa River (the Kichi Sipi) and its many non-human inhabitants. This thanksgiving weekend, I’m grateful for the humans.”


    Today we will talk about Bryozoans. They are 0.5 mm in size aquatic invertebrate animals that live in colonies that are held together by gelatinous secretions. They are filter feeders that consume particles of algae and microscopic crustaceans through a crown of tentacles called lophophores. Snails, insects and fish will eat bryozoans. Around Petrie Island, colonies can be found floating free or attached to submerged trees.

    Photos from this past summer from our FB Group- Petrie Island: Our Small Wilderness- credit to Norman Hooper and Mee Shell.

    #20Celtis occidentalis/ Hackberry

    By Al Tweddle with Sherry Nigro

    Celtics occidentalis, more commonly known as hackberry, is one of the 26 species of trees found at Petrie Island. Our local population of hackberry is the greatest known concentration in the Ottawa area and is considered provincially rare. Hackberry more typically grows in a Carolinian environment and our trees represent the most northerly edge of their distribution.

    Their fruit is unusually high in fat, carbohydrates and protein and has been a food source for animals and humans. The leaves have an asymmetrical heart shape with serrated or jagged edges and the bark is unique for its deep ridges and a raised “warty” texture.

    The hackberry forest at Petrie has a nice mixture of mature and younger trees growing among lush ostrich ferns. It is beautiful and scientifically important, both very good reasons for protecting our hackberry forest!

    #19- Chicken of the Woods

    By Sherry Nigro

    A few years ago I attended a Petrie Island clean up day. As I plucked plastic bags and old bottles from the bushes, I spied a brilliant yellow and orange bracket fungi growing on a fallen tree. I was so excited to discover a new-to-me species.

    Using INaturalist I learned that it is aptly named. The scientific name, Laetiporus sulphureus, is a reference to the bright yellow colour. The common name is chicken of the woods; it is edible when it is young.

    Fortunately the chicken of the woods at Petrie Island is protected from foragers by Park rules that prohibit removal of any plant or animals. This ensures this unique and colourful species is likely up pop up in other places at Petrie Island. Keep your eyes open!

    #18- How we can help

    By Alicia Gilmour

    A few weeks ago on a particularly humid day, I was working in the FOPI office with a couple of my co-workers. I was on my computer making progress on a project, when an older family of 5 arrived at the door. In the mother’s hands was a baby red squirrel. The family said that they were walking down the bike trail when they found 3 baby squirrels that fell out of their nests onto the ground: one healthy, one injured, and one dead. They brought back the healthy one, and I went back with them to find the injured one. We found it where they placed it in a fallen tree nook and saw that it was tired and had a bloody nose, but was otherwise healthy looking. As we found the dead squirrel, we heard a tiny thunk coming from behind us. We ran over to see that yet another baby red squirrel had fallen out of the tree. This one is pretty hyper, but he had an injured ear. We waited a few minutes longer to make sure that it didn’t continue raining squirrels, then we brought the two injured squirrels back in an empty cardboard freezie box. When we got back to the office, we placed all three squirrels in the box with some cut up apples and an old shirt, so that they would feel comfortable. While I was away, my co-workers called the Rideau Valley conservation center who arranged for the squirrels to be brought to them. Then they called Ottawa Bylaw to have them bring the squirrels to Rideau Valley. After about a half an hour of having the three baby squirrels in the freezie box, a by-law officer wearing the full, bulky policeman uniform, arrived at the door, cooed at the three baby squirrels, and then brought them to his police car, to take them to the rehabilitation center. I like this story because it reminds me of the reality of being an animal in the wilderness, and all the hardships they have to overcome to survive; but also because its a story of kindness, and how a handful of strangers took an hour out of their day to save the lives of three adorable baby red squirrels.

    #17 Petrie Island Beavers

    By Michael Ricco

    During the winter months, beavers were tucked away in their lodges, one of which was at the end of the Bill Holland Trail, and another one was along the Basswood Trail, close to Crappie Bay. As March came in, I began to sense a stirring in the woods, and around the 10th of March 2022, following a substantial snowfall, I came across a series of beaver tail trails in the snow that crisscrossed the Sunrise, Bike Path, and Basswood trails. A few days later, I saw a pair of beavers for the first time in 2022, a sure sign that winter was indeed coming to an end. Within a few days of that, I was sighting beavers every day, and one morning, thanks to a tip from a very nice couple, I was alerted to a brood of 4-5 beavers basking outside their lodge on the Basswood Trail. It was indeed a treat to observe the physical and affectionate closeness shared by this family of beavers, and photographing their interactions with each other certainly made this a most amazing beginning to the Spring of 2022.

    Beavers are one of the iconic wildlife critters of Petrie Island. They’re large, semi-aquatic, and considered to be rodents. They build dams and lodges using tree branches, vegetation, rocks, and mud. Throughout Petrie Island, one will find evidence of where they have chewed down trees for building material. On the flip side of their perceived destructiveness, beavers are responsible for their positive impact on biodiversity and the creation of wetlands used by many other species. Blue Herons are a prime example of one species who have taken great advantage of the fishing grounds created by the beavers. Unfortunately, the beaver lodge that existed along the Basswood Trail appears to have been destroyed by the derecho storm that hit Ottawa on Saturday, May 21, 2022.

    #16- Special moments

    By Judy Mulligan

    “Every visit to Petrie Island is unique and being in the right place at the right time can result in a wonderful experience.

    On one of my luckiest walks last year on the Bill Holland trail, I was witness to one of the turtle researchers with a juvenile male snapping turtle (Chelydra Serptina). I had the opportunity to take a few photos of the snapping turtle with his mouth wide open without risk of injury to either of us, before he was released. To learn more about the local turtles visit

    Good luck with your special moments at Petrie Island!”

    #15 Erosion in the Petrie Island Conservation Area

    By Norman Hooper

    “In 1999, I began canoe paddling around the shores of Petrie Island. At that time, only piles of sand from the dredging operation in Cumberland Bay was visible.

    After the company left and the stockpiles of sand were transformed into a playground beach with parking lots and more paths, people and families began to trek and explore, photograph nature and have a greater interest in the island’s conservation of wildlife and its eco-system.

    However, “erosion” has caused much change to the island over the years due to spring floods and severe storms. The western tip of the island once had majestic standing trees as focal points for a variety of birds; today, many trees and about 100 feet of shoreline no longer exist. All along the Ottawa River and some inlets, the same devastation has occurred to the island.

    A more drastic change to the landscape involves the once spit of land between Cumberland Bay and the channel leading to the marina. With” the river’s strong current, an opening has appeared and over time, it has become wider and deeper, causing trees to be washed away and resulting in further shrinkage to the newly formed island’s shoreline. This island will disappear in time!

    In the future, Petrie Island will still be referred to as, “The Jewel of East Ottawa”, but only with careful management.”

    #14 Ottawa’s Own Giverny Pond

    By Charles Ponée

    Most art lovers are familiar with the impressionist painter Monet and his numerous lush paintings of the bountiful and dramatic gardens and ponds that continue to charm those who visit his home in the quaint French village of Giverny. However, most Ottawa area art enthusiasts are less likely to be familiar with our own “Monet’s Pond” located in the heart of the luxuriant Petrie Island Parkland along the Ottawa River, on the outskirts of Orleans.

    Tucked away on the east side of the entrance to Petrie, and just past the marina bridge there is a small body of water that, throughout the summer, turns into an exquisite pond replete with various wetland trees, textural reeds and lily pads adorned with splendid white blooms and luxurious flowering bushes, all visited by turtles, snakes, geese, ducks, song birds, fish and the like. For certain, in terms of scale and human grooming, it doesn’t compare to Monet’s intricately developed garden; however, to us three artists this Giverny version and its environs, when in “full flower”, are truly an impressionist’s delight!

    Throughout the long and tedious months of Covid, two of my local painter “amigos”, Luís Leigh and John Chibuk and I have spent most Tuesdays keenly sketching in and about Petrie Island and its marvelous pond.

    Because it is such a pleasure-filled and delicate spot, we informally christened it “Monet’s Pond”, harking back to so many aspects of that famous garden. While John and I lean to the abstract, Luís, an enthusiast of the Canadian Group of Seven, is committed to the representational style. Our outings are casual, focused on eagerly sketching all aspects of Petrie Island, in all seasons and in all types of weather. Our objective is to hone our artistic skills, discuss various aspects of art, develop material for future studio works, experience the peaceful enjoyment of nature….and enjoy ourselves!

    A bonus to these pleasant creative outings are the numerous and regular encounters we enjoy with other area residents such as photographers and bird-watchers, paddlers and swimmers, park attendants and volunteers, walkers and environmentalists, all of whom also visibly enjoy what this unique setting has to offer.

    This happy trio of artists eagerly encourages the reader to make a summer visit!

    # 13 Yellow-bellied Sapsucker

    By Paul Downing

    “Petrie Island is one of my favorite locations to photograph birds/wildlife.

    One island resident is the Yellow-bellied Sapsucker, a member of the
    woodpecker family.
    You might hear them pecking on man-made wood or metal objects at
    Petrie. This may seem odd but it’s part of their territorial tapping.
    Unlike other woodpeckers, they usually migrate, going as far south as
    As their name implies, they feed on tree sap. They drill neat rows of
    holes in tree bark called sapwells. The sapwells can attract other
    birds and bats.
    Males can be differentiated from females by their red throat.

    by Paul Downing ( on Instagram)

    # 12 Monarch Butterfly

    By Carol Howard Donati

    “ As a haven, and journey-stop for migrating wildlife of all kinds, Petrie Island hosts many butterfly species, including Eastern Monarchs. Monarchs arrive in the summer months, drawn to milkweed plants, both Common and Swamp, that that thrive on shorelines around island. Their eggs, deposited on the underside of milkweed leaves, hatch into colourful, striped caterpillars that feed and grow on the leaves. After pupation, distinctly patterned orange and black adults emerge to explore and feed on the wild gardens of the island. If you are lucky enough to see a Monarch Butterfly resting for a moment on a flower, take a close look and discover the tiny white polka dots decorating its dark body.
    In late summer and fall, Monarchs born at Petrie Island leave and head south on an incredible migration over 1000’s of miles to reach Florida and Mexico. Hopefully, some of the next generation of Monarch Butterflies born there will return north to Petrie Island next year!
    Note- since this blog was written the Monarch Butterfly has been declared as endangered globally.

    #11 Social and individual responsibility

    By Daniel Cadieux
    Social and Individual Responsibility
    “Having roamed the paths of Petrie Island since the 1980s’, I’ve seen it grow from a thriving sand dredging location, to a quiet “best kept secret” natural area to explore, to now a popular local destination for residents to bask in the sun and refresh in the water during the summer months. With this still-new and growing “fame” comes the social and individual responsibility to steward this natural area hotspot (including wetlands, shorelines, forests, and dunes), and help preserve it as both the prime east-end ecological area, and bustling summer hang out spot for families and others to enjoy!”

    #10 Dodder

    By Maha Najjar
    “As I was strolling on one of my favourite paths in Petrie one day, I noticed a plant which I had never seen before. It had beautiful tiny white flowers and bright orange stems that formed a striking contrast with the green leaves of plants around which it was entwined. I took a picture with my “plant app” and found out it was called dodder. When I got home, I looked it up : it turns out dodder is a leaf- and rootless parasite which sucks all its nutrients from its host plants. Being harmful to crops and gardens, it has colorful folk names, such as wizard’s net, devil’s guts, strangle tare or witch’s hair. But although nobody likes a parasite, one fascinating study showed that dodder can actually help its environment: dodder vines often connect different host plants together, forming a network. If any of these plants is attacked by a plant-eating insect, it will emit signals that are then transmitted by the dodder to the other plants in its network. These signals will activate defenses in the unattacked plants that are now alert and ready to defend themselves against their enemies.
    This only confirms what we already know: that every plant, every insect, every bird, every living thing, no matter how harmful they may seem, has its role to play in our world, and we need to preserve each and every one of them if we want our world as we know it to survive.”

    #9 Wood Duck

    By Austin Taverner of the Ottawa Duck Club

    Wood ducks are natural cavity nesters but will use duck boxes – see photo 1. Boxes are installed at Petrie Island by the Ottawa Duck Club (ODC) – most of the work is done in winter. The outings are especially enjoyable at lunch break, as everyone seems to want to show off their best home made cookies or cake – yummy.
    • In the Ottawa area, wood ducks lay an average of 14 eggs. The eggs are incubated only by the female – see photo 2. Those big beautiful eyes, how can you not fall in love with her.
    • After approximately 30 days, ducklings will start to break a small hole through the egg at one end, and work their way around the egg, so the end falls away – like the lid of a jar.
    • The ducklings then push themselves out of the eggs and quickly dry – see photo 3.
    • Within 24 hours, when called by mom, the ducklings will jump out of the nest (up to 50 feet or more for natural tree cavities but approximately 8 feet for ODC boxes).
    • The ducklings can immediately swim and feed themselves, but are tended by mom for 5 to 6 weeks – they can fly at 8 to 9 weeks.

    #8- Trees of Petrie Island

    By Councillor Matt Luloff

    My two favourite things to do at Petrie Island are to take a paddle around the island in a canoe and to take a hike up the Basswood Trail. I am always struck by the beauty and biodiversity of the trees in the area. Petrie is home to well over 20 species of trees, the most common being Silver Maple, Eastern Cottonwood, Common Hackberry, Basswood and American Elm, though if you look hard enough, you can find Butternut, Black Ash, Bitternut Hickory and more.

    I deeply love the peace and quiet the Southern areas of the island offer for contemplation and active meditation. A canoe provides the opportunity to admire the smaller islands that remain largely untouched by humanity. I highly recommend taking a solo paddle in the area and experiencing the calm beauty of Petrie’s South and West sides.

    Les deux activités que je préfère à l’île Petrie sont de pagayer autour de l’île en canoë et de faire de la randonnée sur le sentier des Tilleuls. Je suis toujours ébloui par la beauté et la biodiversité du secteur. L’île Petrie abrite plus d’une vingtaine d’espèces d’arbres, les plus communs étant l’érable argenté, le peuplier deltoïde, le micocoulier américain, le tilleul et l’orme d’Amérique. En regardant plus attentivement, il est également possible d’observer le noyer cendré, le frêne noir, le caryer cordiforme et bien d’autres essences.

    J’aime profondément la paix et la tranquillité que les parties méridionales de l’île offrent pour la contemplation et la méditation active. Une promenade en canoë donne l’occasion d’admirer les petites îles qui demeurent largement épargnées par l’activité humaine. Je vous recommande fortement de pagayer en solo dans le secteur pour découvrir la paisible beauté du sud et de l’ouest de l’île Petrie.

    #7- Peregrine Falcon

    By Mike and Therese Dupuis

    July 3rd, 2021 offered us a close-up encounter with a Peregrine Falcon. Perched in plain sight, high up a dead tree on the Bill Holland Trail.

    The bird sat peacefully for a few minutes but Peregrines can reach speeds of 320 km/h diving towards prey from a kilometre in the air.

    This was our only Peregrine sighting in 2021, we were able to get a few photographs of our chance visit.

    Peregrines became an endangered species in Canada in 1978 after years of declining numbers starting in the mid 20th century. Some are still under the category of Special Concern.

    Hopefully the Peregrine population will continue to rebound and they will drop by more frequently at “Our Small Wilderness”.

    #6- National Indigenous Peoples’ Day

    By Rev. Nancy Arthur Best

    Happy National Indigenous Peoples Day! Petrie Island has been a place for our First Nations to fish and gather for millennia.
    We are honoured to share some reflections from Reverend Nancy Arthur Best, a strong supporter of the Friends of Petrie Island and a proud member of Indigenous Peoples. Meegwetch for your teaching Nancy.

    “I acknowledge that we are on Unceded Territory of the Algonquin Anishnaabeg people.
    Petrie Island is a holy place to me. I am of Mohawk heritage as well as a United Church of Canada Ordained Minister. Petrie Island allows me to embrace both sides of my spirituality. Our Indigenous Teachings use the phrase “Akwe Nia’Tetewá:neren”—all my relations. This embraces the diversity of all creation, on the land, in the water, and in the sky. Petrie Island embodies this.
    Immerse yourself in the multitude of senses experienced year round at Petrie.

    Meegwetch Mother Earth and Turtle Island.”
    Rev. Nancy Best

    #5- Northern Watersnake

    By Paul Lefort

    Northern Watersnake
    Nerodia sipedon sipedon
    La couleuvre d’eau est devenue plus rare, en raison de la destruction de ses habitats. Elle est présente uniquement le long de l’Outaouais et dans la partie sud du Québec, ce qui signifie que ce reptile est susceptible d’être déclaré vulnérable ou menacé. Depuis une vingtaine d’années aucune couleuvre d’eau n’avait été aperçue à l’île Petrie. En 2022, une seule couleuvre d’eau a été vue à l’île. Elles sont relativement abondantes sur la rive nord de la rivière. On peut espérer un accroissement de la population locale. Aspect: écailles dorsales de cette couleuvre sont carénées, coloration sombre avec de larges bandes brunâtres ou rougeâtres, ventre pale avec motifs variables de coloration rouge ou orangé. La tête est entièrement grise ou brune et les lèvres sont marquées de barres foncées verticales. Peut atteindre plus d’un mètre de long.
    La couleuvre d’eau vit en bordure des cours d’eau et des plans d’eau, marais et étangs là où la végétation aquatique est riche. Elle est vivipare, donnant naissance à une trentaine de petits.
    Espèce susceptible d’être désignée menacée ou vulnérable (statut provincial). Principalement présente en Outaouais. Autres populations localisées dans le Sud du Québec.

    THE WATER SNAKE Northern Watersnake Nerodia sipedon sipedon

    The Northern Water Snake has become rarer, due to the destruction of its habitat. It is present only along the Ottawa River and in the southern region of Quebec, which means that it is likely to be declared vulnerable or threatened. For about twenty years, no water snakes had been seen on Petrie Island. In 2022, only one water was spotted on the island, but they are relatively abundant on the north bank of the river. We may hope for an increase in the local population. Appearance: dorsal scales of this snake are keeled, dark colour with wide brownish or reddish bands, pale belly with variable patterns of red or orange. The head is gray or brown, the lips are marked with dark vertical bars. May reach more than a meter. Non-venomous, but sometimes aggressive if disturbed.

    This snake lives along rivers and bodies of water, marshes and ponds where aquatic vegetation is abundant. It is viviparous, giving birth to about thirty young.

    Photo by Malcom Fenech

    #4 Snapping Turtle- A dinosaur at work

    By David Seburn

    Early one morning at Petrie Island I watched a large Snapping Turtle laying her eggs. It was a quiet part of the island and it was easy to imagine I was in a primordial world with this dinosaurlaying eggs like her ancestors have done for more than 200 million years. She laboured for over an hour, then covered her eggs and lumbered back to the river, sliding into the dark water. So many turtle nests end up as food for raccoons and other nest predators. A female Snapper often lays 20-30 eggs but I have seen nests with more than 60 eggs so those nest predators are robbing Petrie of many future turtles. This year we will try to collect and incubate some nests to help ensure a future for Petrie’s turtles.

    #3- Closed Bottle Gentian

    By Sherry Nigro

    There are a few special features that I love about this wildflower.

    I love that they are late bloomers, bringing their vivid blue colour to late summer and fall. The elliptical shaped flowers stay tightly closed which presents a real challenge to pollinators. In fact only bumblebees are strong enough to push their way into the flower. The pink ladybeetles in the photo must be frustrated.

    Another reason this wildflower is special to me is that I found it with the help from our community of nature lovers at Petrie Island. The generosity and passion of the folks who travel our trails and waterways is inspiring; as is the closed bottle gentian.

    #2- Pink Heelsplitter ( Potamilus alatus)

    Walking and photographing at Petrie over the years has revealed to me many intriguing and less-obvious species living here. Freshwater mussels, also called “clams”, live away from shore in shallow water. Live mussels are not easy to observe, even if their more-recognizable empty shells are frequently found scattered on the beaches. Freshwater mussels live out their lives on the river bottom, nestled in the sand, often under or nearby to plants and wood debris. They contribute to the ecology in important ways by filtering and removing toxins from the water and aerating the surroundings with their movements. Globally endangered, freshwater mussels are protected in Ontario. The Pink Heelsplitter is one species that I see regularly at Petrie Island. Named after its pink-tinted inner lining and the sharp edge of its outer shell, Pink Heelsplitters are one of the unseen but important creatures contributing to the rich wetland biodiversity at Petrie Island.

    By Carol Howard Donati

    #1 Great Blue Heron

    By Michael Ricco

    Oh, how I am captivated by the Great Blue Herons. They are easily my favourite bird and the most enjoyable to photograph.

    The Herons love the shallow bays and wetlands of Petrie Island, and this is where I often see them during my morning visits to Petrie Island. They love to tread slowly through the marshes or fly just above shallow water, looking to catch their next snack or meal.

    They share their space freely with the other birds and the waterfowl that populate Petrie Island.

    In 2021 I was most fortunate to photograph this wonderful bird over 2,200 times.