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A diverse population of insects and other aquatic creatures is a good indication of the health of a stream. A stream-walk to collect and inventory these creatures is an effective and interesting way to study streams. Mayflies (Ephemeroptera) are particularly sensitive to pollution and are one of the first creatures to disappear from polluted streams. They are food for many creatures, especially trout, another pollution sensitive creature. |
 In healthy waters they can be particularly abundant, like these gathering by the thousands around streetlights and on car hoods when taking their nuptial flight in the summer. (Don't worry. It's a rental car!) |
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 The cardinal-flower (Lobelia) is one of the most delicate plants we encounter in the freshwater portions of streams. |
 We like to start our stream walk in the upper areas of our watershed, and it is not unusual to see deer and other upland animals. |
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 A patient frog (Rana) waiting for its meal along the quiet stream bank needs to be careful or it might get caught by quick campers. |
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| In wider stretches of the stream and in nearby ponds the painted turtle (Chrysemys) basks in the sun....and, always ready to head for deeper water, keeps an eye on campers. Our explorers are restricted to ankle-deep water. |
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 Sifters and home-made plankton nets capture a great variety of insects and their larvae. |
 What looks like a giant mosquito is actually a harmless cranefly (Nematocera), and like many insects, is good frog food! |
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 Frogs are great wanderers on rainy days and can set up home in most water bodies. |
 As we get downstream into brackish water, we encounter fiddlers crabs (Uca), |
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 We also discover the footprints and scat of mammals that feed here Note the indigestible crab claws embedded in it.Note the crab claw and see to the right for a possible culprit.) |
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| (Right) Fiddlers need to be vigilant at all times since they are food to so many salt marsh creatures, including wading birds. Click here for a information on wading birds and their feeding habits in the marsh. |
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 Damselflies and their larvae are some of the bio-indicators of a healthy freshwater stream. |
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 Delicate damselfly larvae (Odonata) and dragonflies hide among the submerged plants and rocks and eat things like mosquito larvae. |
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 Predatory water striders (Gerridae) catch other insects that fall on the surface. |
 In calm areas like ponds, waterlilies always catch our attention. |
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 The infamous greenhead fly (Tabanus) is the |
 Its biting mouth-parts make it a nuisance to us, but flies are an important food source for birds. |
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In quiet eddies in ponds and freshwater creeks, we
can observe whirligigs beetles (Gyrinidae). Note: if these creatures
are not moving, hit the start buttons or your reset key (F5) or buy a new computer. |
(Above) The only creatures we ever remove from the stream for an extended period to take a close look are mosquito larvae.(Below) This are more likely to be found in isolated waters, marsh pannes and disturbed wetlands. | |
| After our observations are completed...all equipment is collected, any trash we find is removed, anything living is returned to the stream, and Rusty, the frog-hunting retriever, is retrieved. |
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