Tern and Plover Nesting Failed in 2009 on Niobrara River Section

The 2009 breeding season was a failure for Least Terns and Piping Plovers along a portion of the Niobrara River.

Based on three surveys done by seasonal biological technicians of the National Park Service office in Valentine, there were no young raised on the lower section of the Niobrara National Scenic River, according to a report just released by the agency.

The section between the Norden Bridge and the Highway 137 Bridge had been surveyed in six to 12 mile segments between June 16th and July 21st, by agency staff floating in kayaks.

On the first survey, five terns and nesting plovers were noted along the river only between the Highway 183 and Highway 7 bridges:

Table 1: 1st Census (6/16-6/25)
River Segment	Date	Mean Flow (cfs)	Terns/Nests/Eggs	Plovers/Nests/Eggs	Unknown Empty Nest
Norden to Meadville	6/25	885	0/0/0	0/0/0	0
Meadville to Hwy 183	6/18	1010	0/0/0	0/0/0	0
Hwy 183 to Hwy 7	6/16	1200	5/0/0	4/4/14	2
Hwy 7 to Carns	6/17	1120	0/0/0	0/0/0	0
Carns to Hwy 137	6/19	926	0/0/0	2/0/0	0

An increased number of these two species were noted on the second survey in latter June and early July:

Table 2: 2nd Census (6/29-7/7)
River Segment	Date	Mean Flow (cfs)	Terns/Nests/Eggs	Plovers/Nests/Eggs	Unknown Empty Nest
Norden to Meadville	7/7	841	0/0/0	0/0/0	0
Meadville to Hwy 183	7/6	922	10/0/0	8/0/0	4
Hwy 183 to Hwy 7	6/29	848	9/4/10	6/7/22	9
Hwy 7 to Carns	6/30	823	0/0/0	0/0/0	0
Carns to Hwy 137	7/2	754	4/0/0	0/0/0	0

A third survey on July 21 to the river segment where birds had been nesting, did not find any terns or plovers.

The sandbar where the birds had been nesting "appeared considerably altered from the previous visit at the end of June," the report said. "There had been a severe thunderstorm on July 13th, with precipitation exceeding two inches; this may have at least partly accounted for the absence of bird signs."

There was also a higher water flow in the river this season, in comparison to last year.

"The river flows in 2009 were considerably higher than in 2008 (a range of 754-922 cfs versus 580-707 cfs for the second census each year)," according to the report.

Overall, the numbers found increased this season in comparison to 2007 and 2008, the survey results indicate.

Results of Adult Census
	Adult Interior Least Terns	Adult Piping Plovers
2007	4	6
2008	6 (0, 6)	1 (0, 1)
2009	28 (5, 23)	20 (6, 14)

No young of either species had been raised in 2008, according to a NPS report issued last year. Three Piping Plover were hatched in 2007, according to Pamela Sprenkle, the resource management specialist for the NNSR.

Available results indicate a wide-range of known breeding success along this section of the Niobrara River in recent years:

2009-- 0 PP - 0 ILT

2008-- 0 PP - 0 ILT

2007-- 3 PP - 0 ILT

2006-- 0 PP - ? ILT

2005-- 10 PP - 4 ILT

2004-- 7 PP - 4 ILT

2003-- 11 PP - 4 or 5 ILT

2002-- 9 PP - 1 ILT

"No full-time resource manager was employed by the park beginning in the spring of 2007," Sprenkle said, "so discussions were held with resource management staff at the Missouri National Recreational River to determine the best way to handle the summer monitoring. Both because of the reduced personnel available and because of the low numbers of hatchlings encountered in the previous year, it was decided that an adult census would be a reasonable substitute: '...this would allow for population comparisons to previous years and when there is a significant increase in bird numbers, then maybe incorporate the nest/productivity checks.'"

"We (including the folks at the Missouri National Recreational River) decided to continue emphasizing the census over systematic followup visits to the sandbars," she added. "I am re-examining the protocols in conjunction with the development of a long-term resource stewardship strategy."

These surveys are conducted by NPS personnel in conjunction with the agency's management of the Niobrara National Scenic River. Park personnel monitor this 40 mile section each year.

Additional species noted during the surveys were: American Bittern, American Goldfinch, American White Pelican, Bald Eagle, Bank Swallow, Barn Swallow, Belted Kingfisher, Black-capped Chickadee, Bullock's Oriole, Canada Goose (including goslings), Chipping Sparrow, Common Grackle, Common Nighthawk, Common Yellowthroat, Eastern Kingbird, Eastern Phoebe, Eastern Wood-Pewee, Great Blue Heron, Green Heron, House Wren, Indigo Bunting, Killdeer, Mallard, Mourning Dove, Pied-billed Grebe, Red-tailed Hawk, Red-winged Blackbird, Spotted Sandpiper, Turkey Vulture and Yellow Warbler.