On Saturday, July 23, 2016, I stopped by a pipe about a foot and a half in diameter that releases waste-water into a small tributary brook of Mill Creek in cropland about a mile south of New Holland, Pennsylvania to experience what adaptable wildlife was visible around that waste water. Right away I saw an eastern kingbird perched on a plant along the edge of the brook close to where I sat as it waited for flying insects to go by. And within a minute I saw a foot-long snapping turtle in the clear, slowly flowing water that is about two feet deep at most. The turtle, which was about ten feet from me, appeared to be stalking little, mixed schools of black-nosed dace and banded killifish that swam away from it. As I watched the turtle with my binoculars, I saw that its eyes appeared innocent, not sinister as we might expect from a predator. As I continued to view the snapper, I saw a blur flash through my field glasses. I looked away from the glasses and noticed a spotted sandpiper walking and bobbing on a rock right by the turtle! But the sandpiper and turtle seemed to have no regard for each other. Spotted sandpipers are inland sandpipers that raise young and eat invertebrates along streams and ponds away from the coast. Their bobbing as they walk is a form of blending in that makes them resemble debris bouncing in wavelets along tiny shores. As I marveled at seeing these critters so close to each other, and me, I began to think about other species of wildlife I noticed during the last few summers along this bit of brook that waste water flushes into, and then into Mill Creek itself.
The waste water is treated before it is discharged into the brook because dace and killifish have lived in it for several years. And dace are particularly susceptible to pollution. Their presence, alone, tells the water is neutralized before being released into the brook. Both these species of small, stream-lined fish are brown on top to blend into the muddy bottom of the brook for the fishes' protection. I actually see the shadows of these fish on the bottom better than the fish themselves.
Dace and killifish are links in several food chains, including the snapping turtle. A few northern water snakes lurk here and prey on minnows. Occasionally a belted kingfisher drops from the air to snare minnows while, sometimes, a great blue heron or a great egret wades this little waterway to catch the small fish.
Every spring and summer, I see a mallard duck hen with her ducklings, a muskrat or two, a pair of song sparrows and a little group of American goldfinches in the close vicinity of the waste water, but not all at the same time. The ducks are there to shovel up aquatic invertebrates and vegetation while the muskrats eat grass along the banks of the brook. The song sparrows are like shorebirds in that they consume invertebrates from the thin mud flats and shallows along the edges of the brook. And the goldfinches are there to eat alga.
I have heard green frogs croaking along the edges of the waste-water brook. They probably spawn in the slower parts of that little waterway. Frogs are potential food for herons, mink and raccoons that frequent waterways in this county, and elsewhere.
A couple kinds of dragonflies in limited numbers and bluet damselflies in abundance buzz over this brook after mates and flying insects, and land on plants on its shores to rest. These dragonflies and damselflies were carnivorous nymphs in the water of this waterway, including the part exposed to the waste water. There they hunted critters small enough for them to be able to handle.
I've seen at least a few pairs of red-winged blackbirds in the area of the waste water as they hunt invertebrates along the shores of the brook and the tall grasses that border it. The handsome male red-wings are black with red shoulder patches. They sing from the tops of plants along nearby Mill Creek, as they do all over North America, to establish nesting territories and attract females to them for mating.
A few kinds of shorebirds patrol the slender mud flats and shallows of this brook to seize and eat aquatic invertebrates, including where the waste water enters it. Those shorebirds are the locally nesting spotted sandpipers and killdeer plovers, and migrant least sandpipers, solitary sandpipers and lesser yellowlegs, which is also a type of sandpiper. Individual migrant sandpipers, and little groups of a half-dozen or less, are only along this brook early in May when they are going north and in August mostly when they are heading south. But they make our farmland a little more interesting.
Interestingly, too, arrowhead is an abundant emergent plant on the edges of the brook. This plant is about two feet tall, has large, arrow-shaped leaves and lovely, white flowers with three petals by the latter part of July.
And by early September, the edges of this waterway are dominated by the golden, cheering blooms of bur-marigold plants, most of which grow right on the shores of brooks and streams. These blossoms brighten the shores of the little waterways they dominate.
It is amazing the number of species of beautiful and intriguing life that live in a small, human-made habitat, especially one influenced by the daily presence of treated waste water. And there are innumerable other built habitats on Earth that house pockets of nature on this overly-developed planet.
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