The
Tualatin National Wildlife Refuge is a wonderful place to look for birds, any time of the year, because it has wetlands to attract them and open areas that make spotting them easier. But we went there just to look in two small ponds, which are bursting with life. When we arrived, the Pacific chorus frogs were hiding, unseen, and making a positively deafening racket. It was magical! Each burst of song began with one "chorus master" who was gradually joined by others, until the air was ringing. These frogs only grow to about two inches long, and it's quite an impressive sound from such small creatures. I did not have our digital recorder, but had the camera's movie feature to record their song. There's not much to see in the movie, but you can get a sense of the boldness of their sound.
The smaller, shallower pond is also inhabited by fairy shrimp. These tiny crustaceans are very fun to watch! They swim upside down with their many legs waving. Their eggs are laid in vernal pools and must dry out completely with the pool. They hatch in the winter or spring when the pools fill up again. Fairy shrimp are survivors whose eggs have been found to remain dormant for dry periods of 15 years. This strategy helps explain how they have survived since the Upper Cambrian, 500 million years ago, through two mass extinction events.
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| A tiny fairy shrimp. |
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| Pacific chorus frog egg mass. |
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| Buffleheads (females on the left, males on the right) |
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| An oak gall. |
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| Red-tailed hawk. |
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| A pair of coots. |
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| Red-winged blackbird. |
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