EXTRACTS ON NEOTROPICAL MIGRATORY BIRDS

TAKEN FROM PUBLICATIONS SUBMITTED OR IN PREPARATION, BY
BRUCE G. MARCOT AND COLLEAGUES, INTERIOR COLUMBIA BASIN
ECOSYSTEM MANAGEMENT PROJECT, USDA FOREST SERVICE AND
USDI BUREAU OF LAND MANAGEMENT

Bruce G. Marcot
Wildlife Ecologist
these extracts compiled:  19 August 1997

[note: literature cited is not included here; please refer to the original papers]

==============================================

from:

Marcot, B. G., M. Castellano, J. Christy, L. Croft, J. Lehmkuhl, R. Naney, R.
Rosentreter, R. Sandquist, and E. Zieroth.  In press.  Terrestrial ecology
assessment.  Pp. xxx-xxx in:  T. M. Quigley and S. J. Arbelbide, eds.  An
assessment of ecosystem components in the interior Columbia Basin and
portions of the Klamath and Great Basins.  USDA Forest Service General
Technical Report PNW-xxx.  USDA Forest Service Pacific Northwest
Research Station, Portland, OR.  xxx pp.
 

Neotropical Migrant Birds—  Among 132 species of neotropical migratory birds
(NTMB) that breed in the assessment area, 38 species have been adequately
sampled in breeding bird surveys from which to detect statistically significant
population trends over two time periods; 1968-1994 (26 years), and 1984-1994 (10
years).  Fourteen species showed significant declines over the 26-year period, and
13 species showed significant declines over the 10-year period.  Similarly, 13 and
12 species showed significant increases over those periods, respectively.  Seven
species [killdeer (Charadrius vociferus), olive-sided flycatcher (Contopus
borealis), willow flycatcher (Empidonax traillii), red-winged blackbird (Agelaius
phoeniceus), western meadowlark (Sturnella neglecta), Brewer's blackbird
(Euphagus cyanocephalus), and Brewer's sparrow (Spizella breweri)] showed
consistent long-term declines over both time periods.  However, five of these seven
species occur in low-elevation wetlands or open shrub habitats largely off FS and
BLM lands, and thus are not likely to be heavily influenced by FS and BLM land
management activities.  The two remaining species are both flycatchers and are both
likely influenced to some degree by FS and BLM land management.

Some 16 habitats (vegetation types) were included in the assessment of NTMB
status and trends.  Riparian vegetation is used by more species (64 percent of all
NTMB species) than any other habitat.  Other habitats that are used by relatively
high numbers of NTMB species include young coniferous forest (38 percent) and
old/mature forest (35 percent).  Among all species with significant 26-year
population trends, nine habitats had more species with decreasing populations than
species with increasing populations, whereas seven habitats had more increasers.
Five of the 16 habitats analyzed with regard to NTMB trends were identified
collectively as potentially needing higher conservation priority:  riparian vegetation,
old forest, shrub-steppe, native grasslands, and juniper woodland.  Priority habitats
were identified based on declines in populations of associated NTMB species and
on the habitats' vulnerability to ongoing management activities.  See Appendix E for
information on species that have undergone significant declines and increases over
the 10- and 26-year time periods.
 

Appendix E.  Neotropical migratory landbirds in the Columbia River Basin for which Breeding Bird Survey sample
size is sufficient (recorded on >14 routes) to quantify significant long-term declines or increases in population trends,
over 10-year and 26-year period.  Numbers in table are percent changes of poplations over the time periods shown.
 
 
                                                              Decline
Increase

Species                        Nest Layera              26 yr          10 yr                   26 yr
10 yr

Osprey                             CA
 6.4***

Red-tailed Hawk                    CA                                                           4.3***
  4.0**

Golden Eagle                       CA
 10.9**

Killdeer                           GR                   -4.3***        -10.5***
 

Long-billed Curlew                 GR                                                           5.1***
 

Mourning Dove                      SH                   -2.2***
 

Red-naped Sapsucker                CA                                                          12.0*
 

Calliope Hummingbird               CA                                 -13.4*
 

Olive-sided Flycatcher             CA                   -2.9**          -4.2**
 

Willow Flycatcher                  SH                 -  2.5**          -4.3***
 

Gray Flycatcher                    SH
  13.6**

Say's Phoebe                       CA                                                             5.4*
 

Horned Lark                        GR                   -2.9**
 

Cliff Swallow                      CA                                                             2.8***
 

House Wren                         CA                                                             4.4**
    5.7*

Marsh Wren                         SH
    8.8*

Mountain Bluebird                  CA                                                             4.0***
    8.1**

American Robin                     CA                                  -1.5*
 


                                                                       Decline
     Increase

Species                        Nest Layer            26 yr          10 yr                       26 yr
 10 yr

Gray Catbird                      SH                                                             4.0**
  6.3***

Loggerhead Shrikeb                SH                 -2.7**
 

Warbling Vireo                    CA                                                             4.1**
 

Orange-crowned Warbler            GR                                                             3.5*
  7.5**

Yellow Warbler                    SH                               -2.1**
 

Townsend's Warbler                CA                                                             5.2***
 

Common Yellowthroat               SH
  2.8*

Black-headed Grosbeak             SH                                                             4.8***
  5.4***

Rufous-sided Towhee               GR                                                             3.5*
  7.6***

Chipping Sparrow                  SH                -2.7***
 

Brewer's Sparrow                  SH                -1.3***          -4.3***
 

Lark Sparrow                      SH                -2.9**
 

Savannah Sparrow                  GR                              -3.2*
 

Song Sparrow                      SH                -2.7***
 

Red-winged Blackbird              SH                -1.5*           2.3*
 

Western Meadowlark                GR                -0.8*          -3.7***
 

Brewer's Blackbird                SH                -1.3*          -4.3***
 

Pine Siskin                       CA                                8.8***
 

American Goldfinch                CA                -2.1*
 

 
 
    *:P < 0.10
   **:P < 0.05
  ***:P < 0.01
    a Nest-Layer abbreviations: CA = subcanopy/canopy-nesting species; GR = ground-nesting species;
      SH = shrub-nesting species, based on characteristics described by Ehrlich and others (1988) and Martin
      (1993).
    b Federal candidate (category 2) for listing under the Endangered Species Act.
 

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from:

Marcot, B. G., L. K. Croft, J. F. Lehmkuhl, R. H. Naney, C. G. Niwa, W. R.
Owen, and R. E. Sandquist.  Submitted.  Macroecology, paleoecology, and
ecological integrity of terrestrial species and communities of the interior
Columbia River Basin and portions of the Klamath and Great Basins.  General
Technical Report PNW-GTR-XXX.   USDA Forest Service.   XXX pp.
 

Species that migrate and spend part of their year elsewhere but that restrict their
distribution during one part of the year to a specific region (such as the basin
assessment area), are called semiendemic species by Garza (1996).  Semiendemics
can include Neotropical migratory birds and other species that occur only seasonally
in a given region.  Garza argues that species that are confined to a specific
geographic region, even if only for a portion of the year, still should be considered
as restricted to that area for purposes of habitat conservation.  Because our range
maps show neither season of use nor migration range beyond the basin assessment
area, our designation of migratory species into endemism and percentage of range
classes approximates the concept of semiendemics.  Thus, some migratory species
might occur as semiendemics in the basin assessment area but rank only as range
categories A, B, or C.