The Truth About Vernal Pools

The Truth About Vernal Pools

by | Aug 24, 2023 | Creek and Stormwater, What's New, Wildlife Protection

Why do we need vernal pools?

The question was posed recently on a walk along Bolin Creek: Can vernal pools be easily relocated, if Bolin Creek is paved?

According to the EPA, vernal pools – or mini wetlands – are a valuable and increasingly threatened ecosystem. These mini pools are rapidly disappearing from our landscapes, as pavement and bulldozers replace the natural forest floor. As a result, we are in danger of losing the rare and important habitat found in these small pools, such as salamander

Vernal pools are miniature wetlands that provide habitat for numerous rare plants and animals that are able to survive and thrive if they can reproduce in water. Plants and animals that spend the dry season as seeds, eggs, or cysts, require a wet environment to grow and reproduce when the ponds are again filled with water.

It turns out on this walk along Bolin Creek, that there is a debate about whether vernal ponds can be recreated as in nature. What does the scientific literature say? One of the best reviews of the literature on relocating vernal pools comes from the University of Maine and its center on sustainable solutions. In this scientific paper, researchers state: “Our review of the literature indicates that vernal pool creation is an imperfect science and should be used as a last resort after exhausting more reliable protective methods…Vernal pool ecosystems are difficult candidates for creation because the community structure is as tied to the surrounding forested ecosystems as to the actual pool depression and because pool function is so tightly tied to hydrology.” (Creating Successful Vernal Pools: A Literature Review and Advice for Practitioners.)

Vernal pools matter to community residents who love their forest. If the Town were to decide to pave the length of the riparian buffer with a cement bikeway, the puddles and vernal pools will be gone.

Now we’ve learned vernal pools are super difficult to replace, why would we mess with nature and destroy what can’t be replaced? Instead let’s follow North Carolina’s Jordan Lake rules, protect the Triangle’s drinking water, and save the creatures: Keep Bolin Wild!

(PHOTO: Marbled Salamander female guarding her clutch of eggs in the dry pool basin. Credit: Jack Ray)

No Buffers, No Birds

No Buffers, No Birds

by | May 19, 2023 | Wildlife Protection

Bolin Creek in Carrboro has many places where the riparian vegetated edge of the creek is intact. This zone is vital to our wildlife. When you remove that riparian buffer, the nature of the creek changes. The Barred Owls in the photo are a mated pair who have raised many owlets in the past years. This year they successfully fledged two healthy owlets. The nest was located within that riparian border of trees, and surrounded by low vegetation. The nest itself was only ten yards from the creek itself. If that riparian is removed, the Owls won’t die. They are married to the territory, but they will have a smaller area to hunt for snakes and amphibians. There will be less available food sources.

When the owls have less food readily available, the female may not have the stores necessary to produce eggs, so in response, she might produce one egg in the next year. This applies to all wildlife in the riparian zone. Summer nesting Hooded Warblers rely on that border for nesting sites, and these tiny warblers consume thousands of caterpillars and invertebrates to feed their nestlings.

{Carrboro’s proposal to put pavement next to the creek will reduce habitat.}  If habitat is reduced, there are fewer territories for the warblers, and less to eat within that territory. Habitat destruction has a slow effect on all wildlife, from the top predators on down the food chain to our creek invertebrates. Fewer fish in pavement heated water (depleted of oxygen), means fewer snakes to feed the owls, and on it goes, in a cascade that reduces the wildlife in an area that was formally rich in wildlife.

The bottom line is that if we eliminate stream buffers, we lose important bird species.  No buffers, no birds.

–Mary Sonis Photographer of Bolin Forest