For an hour one afternoon toward the end of April of this year, I stopped at one of my favorite wildlife places close to home in New Holland. This spot is dominated by treated wastewater from New Holland businesses that flows constantly into a brook in a cow pasture.

What fascinates me about this watery habitat is the number of wildlife species in it and along its margins, all of which have been, and are, exposed to the wastewater.

Mixed schools of banded killifish and black-nosed dace swim into the current of the brook and wastewater, as each fish watches for invertebrates to eat. Dace are a kind of minnow that needs clean water to thrive, which, apparently, this brook has.

Looking closely at the aquatic vegetation on the shallow edges of the brook with binoculars, I saw three green frogs, sitting half submerged and camouflaged among that water-adapted plant life.

Frogs have thin skins and die in outdoor swimming pools with chlorine in them. But there those frogs sat, watching for invertebrates in a mix of rainwater and treated wastewater.

I’ve seen other creatures in that wastewater brook, attempting to prey on the minnows and frogs in it. I’ve seen several northern water snakes in it over the years and a young snapping turtle, but not all at once. And, occasionally, I’ve seen a great blue heron or a great egret stalking minnows and frogs.

A few muskrats live permanently in that brook. They dig burrows in the stream banks at the usual water level and slant them up above the water line. These rodents eat grass, arrowhead roots, and other vegetation along the brook. And, without doubt, muskrats and other critters drink the brook water.

Other bird species regularly frequent this brook. Mallard ducks eat aquatic vegetation there. Song sparrows, common grackles, red-winged blackbirds, killdeer plovers, spotted sandpipers, and Wilson’s snipe, another kind of sandpiper, patrol the narrow, muddy shores of the brook to catch and ingest invertebrates during spring and summer.

Song sparrows live permanently along that brook and nest in tall grass there. And little groups of American goldfinches consume algae from the shores of this brook in summer. The yellow-and-black male goldfinches resemble flowers on the edges of the water.

Small, thin bluet damselflies, which are blue, feed on flying insects and spawn in this brook in summer. The nymphs of these pretty insects feed on invertebrates on the brook’s muddy bottom.

Water from local business is obviously treated before being released into my favorite brook. The proof is the variety and numbers of wildlife living in it for years.


Clyde McMillan-Gamber is a retired Lancaster County Parks naturalist.

Have questions?

We are just a click away!