[Birdtalk] Rails at Bear River - grebe nesting when, why?

[Betsy Beneke]

Thought I'd give an update to the rail chick situation at Bear River - as well as staging a question about grebe nesting.
 
Refuge tour guides Alice Lindahl and Marie Kase were on duty today and reported still seeing rail chicks on the auto tour route, although not in the numbers seen last week.
 
The site on the west side of the tour loop where we originallyh saw lots of chicks has dried up and they didn't see any rails there.  All birds viewed were on the southern portion of the tour.  If you're driving out, I'd suggest heading south (actually southwest) from the River Delta Interpretive Site (by the restrooms) to the corner with the viewing platform, then turning right or west, and looking for rails on the south side of the road for the nest 2-3 miles.  There are also lots of grebe families in Unit 2, which is the management unit encircled by the tour route, or the right side, or north side, of the road in this general area.  It appears to have been a good year for grebe production!
 
I'd like to initiate a dialogue here - regarding western and Clark's grebe nesting.  What do you all know about water levels, breeding biology or other factors that influence when these species nest in our area?  There are grebes on the refuge that are only a week or two into incubation.  There are pairs with newly fledged young.  There are pairs who have chicks that are 3/4 grown.  Are late nesters actually re-nesting?  Are there younger pairs who took a while to figure things out?   WHY do some pairs start nesting soon after they arrive in spring, and others that wait until mid summer?  Keith?  Jack?  John?  Colby?  Others?
 
Is this a question which might be answered after a detailed study?  You know that Bear River Refuge, besides being a giant nursery, is also a giant study area.  I/we (Bridget Olson and I) would love to have an answer to this question...
 
Betsy Beneke


      
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