Saturday, April 30, 2011

Johnny's Dipper Nests

For the previous Dipper surveys, Johnny has been relegated mostly to sitting in a folding chair by the car, since hiking has not been agreeable with his sciatica. That has made him feel, to use his word, "useless". Of course, he is definitely not useless because he drives from one point to the other to pick me up after I've beat the bushes in between. But I know what he means. Yesterday, all that changed.

First, he was able to do a little hiking. On one such he spotted a Dipper carrying moss to a presumed nest under a bridge... where we were unaware of a Dipper nesting in any previous year. This may be the elusive Milepost 3 pair's nest beginnings... although it is closer to Milepost 2.5 than 3. Here's the bird with a mouthful of moss it is trying to take to its nest. Turns out we were too close for comfort so we left.

Johnny's other nest find was truly amazing. We had stopped at a campground where I thought two Dipper territories collide (how wrong I must have been). I looked downstream from the campground while Johnny looked upstream. He almost immediately saw a Dipper on a rock. Soon it was joined by a second Dipper. One carried food to a spot in the bank out of site from the campground. This pair already had nestlings! I hiked up the road to where I could look back and see the nest site. Never would I have guessed a Dipper to nest there... so close to an area people frequent and without steep rocky banks or high banks of any sort. But apparently, the bank is high enough and the tree roots provide a mossy cavity. Here is the sentinel, keeping an eye on us as his mate carts food to the nestlings.

Whether this is a pair previously unknown to us or the pair just upstream, I don't know. The upstream pair had a nest that has been used in past years and was in use on our first trek this April. Alas, we have been unable to detect any activity at that nest on our last two trips... yet there is always a Dipper feeding upstream. Might they have moved their housekeeping downstream while still foraging above their previous nest?

"The literature" states that Dippers nest in about the middle of their 1/2 to 3/4 mile territories. I hope to figure out, eventually, if this holds true for the Dippers of Agency Creek. It would seem that territory size might vary greatly according to the quality of feeding areas on a stream as well as suitability of nesting sites. Although, judging from the campground nesters, some Dippers have lower standards for nesting sites than do others.

Besides finding two Dipper nests, Johnny's eagle eyes found a white eggshell at the entrance to the Asinine Bridge pair's nest. This is the nest we can watch from inside our car. While we did so, one bird carried off the egg shell while a second parent brought food immediately after. My photo is blurry of the eggshell, but trust me, that's what it is.

In one exciting (if you're an American Dipper surveyor) afternoon, Johnny dispelled any notion of his perceived "uselessness".

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