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RESPONDENT
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Joseph Liebezeit
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SITE NAME
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Kuparuk Oilfield, USA
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| Contact details
(phone/fax//e-mail//address): |
| 503-241-7231/503-241-7925(fax) // jliebezeit@wcs.org // Wildlife Conservation Society, North America Program - Pacific West office, 718 SW Alder Street, Suite 210, Portland, OR 97205, USA
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PROJECT DETAILS |
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Project name:
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Nest survival of tundra-nesting birds and human development on the North Slope of Alaska
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Start of survey:
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End
of survey: |
Team
size: |
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6.06
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25.07
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4
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WEATHER
CONDITIONS
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| Season phenology: |
average
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Weather conditions: |
| The Kuparuk River ice break-up occurred approximately May 30th (just before our arrival to the site). Average snow cover was approximately 20% on 9 June when we began re-establishing study plots. Days were consistently warmer than in 2003 for much of the season. Mosquitoes emerged on 16 June this season compared to 26 June during the colder 2003 season. There also were more sunny days in 2004. There were no heavy rain or snow storms in 2004.
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| Date of ice-break on
rivers: |
30.05
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| Date of final loss of
snow: |
16.06
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
low
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Breeding conditions:
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We discovered and monitored all nests on (or near) 24 10-ha study plots every 2-6 days until nest fate was determined. We discovered 198 nests of seventeen species from 10 June to 26 July. Of the 198 nests, 68 were discovered off plot. One hundred twenty-six nests successfully hatched/fledged and 61 failed. We were unable to reliably assess the fate of 11 nests. Nest predation was the only documented cause of nest failure. Mayfield estimates of nesting success for the 4 most common species were: Lapland Longspur (n=38): 0.526, Pectoral Sandpiper (n=27): 0.453, Semipalmated Sandpiper (n=17): 0.924, and Long-billed Dowitcher (n=16): 0.186.
We conducted three 10-minute point count surveys for potential nest predators on all plots. We conducted 3 replicates of this survey on all plots during the course of the season. A total of ten species of potential nest predators were detected (n= # of detections): Glaucous Gull (n = 98), Long-tailed Skua (n = 42), Arctic Skua (n = 41), Common Raven (n = 6), Unidentified Skua (n = 6), arctic fox (n = 6), Short-eared Owl (n = 3), Unidentified raptor (n = 3), Golden Eagle (n = 2), Northern Harrier (n = 2), Pomarine Skua (n = 1), and Sabine's Gull (n = 1).
We discovered fewer nests in 2004 compared to 2003 (198 vs. 223) even though we had the same amount of work effort. Thus, overall nest densities were lower in 2004 compared to 2003 (51.7 nests/km2 vs. 64.6 nests km2 in 2003). More nests were successful in 2004 compared to 2003 (64% vs. 56%). We did notice more Short-eared Owls earlier in the season (first week or two of June) compared to previous years. However, by mid-June observations of short-eared owls were only occasional.
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Rodent dynamics:
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| All 4 observers during almost 2 months in the field only observed lemmings twice.No trend in lemming abundance was apparent during the course of the season. We did not capture lemmings.
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Rodent species recorded:
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Summary
of fauna studies: |
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