PRRIP Governance Committee Meeting and Materials

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? and subsequent restoration brought together a diverse group of public and private partners whose goal was to improve habitat for at-risk wildlife. The restoration included tree removal, river recontouring and the construction of several experirriental nesting islands. In the fall of 2006, just weeks after the restoration was completed, three federally endangered whooping cranes roosted on the site. In the summer of 2007, biologists located 10 nests cf ihe federally endangered least tern and two nests of the federally threatened piping plover using habitat restored as part of the experimental nesting islands. This was the first documented use of nesting on river sandbar habitat on the central Platte River by these species in more than a decade. In addition to the tern and plover nesting documented on constructed islands at the Dinan BCA, two tern nests and one plover brood were documented on two river sandbars on the Dipple Tract, just downstream of the confluence of the north channel and the Platte, about 1.5 miles downstream of the Gibbon Bridge. Neither of these two sandbars on the Dipple Tract were constructed sandbars, although the river channel was disced to remove vegetation in the fall of 2006. There were three natural pulses during the winter/spring of 2007 that apparently built these two sandbars high enough to support subsequent nesting. Mean daily flows (provisional) of 9,350 cfs, 4,870 cfs and 3,730 cfs were recorded at Kearney on February 11, Apri125 and June 2, respectively. It should be noted that the February 11 value occuned during a period of missing record, andlor gage height affected by icing conditions. Considering travel-times, the corresponding flows at the upstream Overton gage and downstream Grand Island gage were considerably less (see Appendix G-Figures 2, 3, and 4, pages 43-45), and/or the subsequent peak flow at the Grand Island gage may be the result of icing conditions influencing water movement from the Kearney to Grand Island gage (approximately 5-days travel time from the Kearney peak on 2/17/07 to the Grand Island peak on 2/23/07). Although the sandbars were quite low in comparison to the islands constructed at the Dinan BCA, an established piping plover nest on the Dipple Tract apparently survived the June 2 natural pulse. Although low storage and inflow conditions persist far Lake McConaughy, compared to WY06, WY07 saw improvements in summer flow conditions in the habitat reach, primarily due to precipitation events below Lake McConaughy and periods of EA releases. Although drought conditions and system constraints made EA augmentation of river flows impractical during the past four nesting seasons, improving flows during the summer period remained an overall Service priority in WY07. Based on the WY07 experience and an anticipated greater likelihood of nesting in WY08, improving flows during the summer period is now considered a higher overall Service priority (see Table 2, page 16). The primary purpose of the 2007 summer EA release was to support flows for forage fish production (for least terns, whether nesting on the river or on nearby sandpits), and macroinvertebrates for piping plovers (again, whether on river or sandpit), and provide some degree of predatar barrier (for riverine least terns and piping plovers). EA releases began on June 28 when the higher flows which occurred in early June substantially declined and flows at the • Kearney gage dropped below 100 cfs. This time-frame also coincided with Ms. Sharon Whitmore (EA Manager) accepting a new position with the Service and leaving the Nebraska Field Office. Water Year 2008 EA AOP 6 October 15, 2007