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SUMMARY The number of nests and nests that hatched interior least tern >_ 1 chick was higher <br />during 2008 and 2009 than 2007 (Table 5). The number of interior least tern chicks /nest initiated <br />during 2008 was lower than 2007 and 2009, but we attribute that to the partial loss of nests <br />(damage to some eggs) associated with the 2008 May rain event. The interior least tern nest- <br />based fledge ratio, however, was 17% and 4% higher during 2007 than 2008 and 2009, <br />respectively. We did, however, observe a slight increase in the total number of interior least tern <br />fledglings during 2008 and 2009. Daily, incubation - period, and brooding - period survival rates <br />for interior least terns increased steadily from 2007 -2009 and tended to be higher at sandpits <br />than river -island sites. <br />The number of piping plover nests initiated during 2007 and 2008 were similar (Table 5); <br />however, the number of nests that hatched ?l chick was nearly 50% lower during 2008. We also <br />observed a 37% decline in the proportion of chicks that fledged from 2007 to 2008. The 23 -24 <br />May, 2008 rain event can likely be attributed to the decreases we observed in the number of <br />piping plover nests initiated and the reproductive success of nest during 2008, as several nests <br />were reported to have been flooded or damaged by hail. The number of piping plover nests <br />initiated during 2009 was >30% lower than 2007 or 2008, but the proportion of nests that <br />hatched >_1 chick during 2009 was only 17% lower than 2007 and was 68% than 2008. The <br />number of chicks /nest initiated during 2009 was only slightly lower than 2007; however the <br />proportion of chicks that survived to fledging was similar to 2008, but was 33% lower during <br />2009 than 2007. Similar to interior least terns, piping plover nest and brood survival rates tended <br />to be higher at sandpits than river -island sites, which could indicate sandpits may be the most <br />critical habitat currently available for maintaining viable populations of these birds along the <br />central Platte River. <br />The numbers of piping plover and interior least tern adults, nests, chicks, and fledglings <br />documented at the Broadfoot - South sandpit represent minimums present during 2008 and 2009 <br />(Tables 3 and 4, respectively). Surveys to determine exact counts of birds were hindered by the <br />large number of birds present at the site, size of the area, availability of hiding cover for <br />fledglings and adults, and limited access to the sandpit. Interior least tern and piping plover <br />success rates (chicks and fledglings /nest) were likely affected by the limited access and visibility, <br />especially during 2008 when we observed 8 interior least tern nests and 8 piping plover nests, but <br />only observed 2 chicks and no fledglings of either species. It was interesting to note that all <br />interior least tern and piping plover sandpit nests observed during 2008 and 2009 were located <br />between Kearney and Lexington, NE while all river island nesting occurred between Grand <br />Island and Kearney, NE. <br />PRRIP 2008 -2009 Tern /Plover Report Page 24 of 42 <br />