A Tiny Beetle, A Big Threat: How the Emerald Ash Borer Will Transform Oaks Bottom

November 15, 2025

In September 2025, an invasive beetle no bigger than a sunflower seed was discovered at the David Douglas Aquatic Center in Northeast Portland. For those who love Oaks Bottom Wildlife Refuge, this news marks the beginning of a profound transformation. The emerald ash borer (EAB) has arrived in Portland, and with it comes the near-certain …

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Harmful Algae Blooms at Oaks Bottom

September 12, 2025

by John Sparks In April 2025, Oregon Health Authority experts tested the waters of Wapato Marsh at Oaks Bottom and found a “concerning” level of microcystins at 191 μg/l (micrograms per liter). (Microcystins are toxins produced by cyanobacteria; the other major cyanotoxin is cylindrospermopsin.) Accordingly, in May, warning signs were posted on the trails at …

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Summer Nature Walk – July 2025

July 19, 2025

Friends of Oaks Bottom held its summer nature walk at the Bottom on Friday, July 11th. The refuge was a lush green oasis with swallows of several species diving and darting over the waters of Wapato Marsh snagging insects. Other summer residents included kingfishers, Canada geese, mallards, gadwalls, and wood ducks. We spotted a couple …

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What’s with the Water?

July 7, 2025

By Ezra Cohen A stark change has marked the transition from spring to summer in Oaks Bottom this year. The lake is drying up. Mud has crept outward from the edges of the basin, leaving dirtied, rivulets of water in its wake. Visitors to the refuge have noted this change, often worriedly, and theories abound: …

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A small, green and brown bird with a long skinny beak perches on a narrow branch.

The Tiny Architects Among the Trees: Anna’s Hummingbirds at Oaks Bottom

June 10, 2025

If you’ve ever walked the trails at Oaks Bottom Wildlife Refuge and caught a glimpse of something tiny zipping past — a flash of green, a glint of rose — chances are you’ve crossed paths with one of the refuge’s smallest residents: the Anna’s hummingbird. These birds are not just eye-catching; they’re remarkable in every …

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Get Your Ducks in a Row: The Common Ducks of Oaks Bottom

May 18, 2025

Article and photos by John Sparks In recent years, 23 species of duck have been observed at Oaks Bottom, including two exotics (Muscovy duck and Mandarin duck). Some ducks, such as red-breasted merganser, cinnamon teal, greater scaup, and common goldeneye, pop up only occasionally. Others are seen with seasonal frequency; these include ring-necked duck, bufflehead, …

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FOOB Work Party: April 12th, 2025

April 15, 2025

Getting instructions – Photo: Andrew Cohen On April 12th, Friends of Oaks Bottom worked on mulching plants in Oaks Bottom’s South Meadow. These young native plants (Oregon grape, spiraea, serviceberry, etc.) need some protection in order to survive our dry summers. There were 18 volunteers, including a cohort of Youth Conservation Corps (YCC) members, as …

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The Frogs of Oaks Bottom

Leave a Comment / January 21, 2025

Article and photos by John Sparks Three species of frog, one of them a predatory interloper, call Oaks Bottom home. Two native frogs, the well-known Pacific chorus frog and the red-legged frog, seem to be increasing in numbers. The “interloper” is the American bullfrog, which – alas – is the amphibian you are most likely …

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2024 – Year in Review

Leave a Comment / December 30, 2024

As the end of the year approaches, we wanted to take stock of all the wonderful work that we’ve done together to take care of our beloved refuge. Here are the highlights. Jenna and Wayne (FOOB crew leaders) with Christian (Portland Parks) at a litter pickup in July Over the course of the year, we …

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Fall Nature Walk: November 9th, 2024

Leave a Comment / November 14, 2024

Hooded merganser male (Lophodytes cucullatus) There were nine attendees on Friends of Oaks Bottom’s fall nature walk, Saturday, November 9th. Joshua Meyers and John Sparks were the official guides, but we were fortunate to be joined by Laura Guderyahn, one of Portland Parks’ five urban ecologists. Laura contributed much interesting information about refuge projects. It …

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Sellwood Flower Company Raises $250 for Friends of Oaks Bottom

Leave a Comment / August 13, 2024

On August 10th, Sellwood Flower Company, Sellwood’s premier flower shop located in an old Victorian on Sellwood’s Antique Row, celebrated the birthday of shop-bird, Alouette and donated ten percent of all sales–$250–to Friends of Oaks Bottom. Shop owner Kerri Evans, who wanted the proceeds to go to a place that protects birds, thought Friends of …

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