Breeding Bird Survey Results 2001

Abundance
The 2001 Breeding Bird survey took place June 8 - June 21.  A total of 4,318 individual birds representing 51 species of birds was recorded along the 13 permanent routes on the INL.  This is slightly below the average of 4,590.4 birds per year recorded from 1985-2000, and the lowest recorded since 1991.  In part, low number of birds counted at the INL in 2001 may be related to below average precipitation and above average temperatures.  Dry and warm springs are correlated with lower bird counts on the INL, and in 2001 several species of birds dependent on surface water were absent or infrequently counted.  

Bird counts for sagebrush obligate species, such as Sage Sparrows (Amphispiza belli), Brewer's Sparrows (Spizella breweri), and Sage Thrashers (Oreoscoptes montanus) were lower than in recent years, perhaps as a result of fires on the INL in the past two years, which have reduced the amount of shrub cover along three routes (Big Lost River, Tractor Flats, and TRA).  


No surveys were conducted in 1992 or 1993.

Species Richness
In 2001, the total of 51 species detected during surveys was slightly below the average of 55.8 7.6 recorded from 1985-2000.  No new species were observed on BBS survey route in 2001, and the total number of species detected along the routes remains at 112.  
 

Overall, the five most numerous species in order of abundance were:

  • Horned Larks (Eremophilia alpestris)
  • Western Meadowlarks (Sturnella neglecta)
  • Brewer's Sparrows (Spizella breweri)
  • Sage Thrashers (Oreoscoptes montanus)
  • Sage Sparrows (Amphispiza belli).  

These five species together comprised 70.9% of the birds detected.  Similarly, these species accounted for 71.4% of all birds observed from 1985-2000.  Although there have been minor shifts in the order over the years, it is clear that these five species are dominant components of the ecosystems at INL.

Comparisons with Long-term Averages
No species were recorded at significantly greater numbers than in previous years (i.e., greater than 2.5 standard deviations above their 1985-2000 averages).  However, large flocks of Franklin's Gulls (Larus pipixcan) were observed at the site for the first time since 1989
, as they foraged on semi-periodical cicadas that seem to hatch only once every 12 years..  

Several species recorded in previous years were not observed in 2001.

  • American Coot (Fulica americana)
  • Blue-winged Teal (Anas discors)
  • Cinnamon Teal (Anas cyanoptera)
  • Redhead Duck (Aythya americana)
  • Ruddy Duck (Oxyura jamaicensis)
  • Willet (Catoptrophorus semipalmatus)
  • Sage Grouse (Centrocercus urophasianus)
  • American Avocet (Recurvirostra americana)
  • Burrowing Owl (Athene cunicularia)
  • Yellow-headed Blackbird (Xanthocephalus xanthocephalus)
  • Cliff Swallow (Hirundo pyrrhonota)
  • Northern Rough-Winged Swallow (Stelgidopteryx serripennis)
  • Mountain Bluebird (Sialia currucoides)
  • Lark Bunting (Calamospiza melanocorys)
  • Lazuli Bunting (Passerina ciris)

Species of special concern recorded in 2001 included:

  • Long-billed Curlews (Numenius americanus) N=2
  • Ferriginous Hawks (Buteo regalis) N=12
  • Swainson's Hawks (Buteo swainsoni) N=3
  • Loggerhead Shrikes (Lanius ludovicianus) N=15  

The INL continues to support species of birds that are low or declining in number throughout the Intermountain West.


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