Central Valley Grasslands:

California’s Highest Conservation Priority?

How are the birds associated with these CV

habitats doing?

Data Sources for Avian Population Trends

• Christmas Bird Count (CBC)• Over 2000 15-mile diameter circles across N.

America• More than 100 years of data

Data Sources for Avian Population Trends

• Christmas Bird Count (CBC)• Over 2000 15-mile diameter circles across N.

America• More than 100 years of data

• Breeding Bird Survey (BBS)• Over 4100 25-mile roadside routes• More than 40 years of data

WATERBIRDS: waterfowl, shorebirds, herons, etc.

Swans, Geese and Dabbling Ducks

GWF Goose Wood Duck GadwallAmerican Wigeon Mallard

Cinnamon Teal

Northern Shoveler

Northern Pintail

+++ +++ + + - - +++ +++ - - -

+++ increasing trend, P<0.001++ increasing trend, P<0.01+ increasing trend, P<0.05- - - decreasing trend, P<0.001- - decreasing trend, P<0.01- decreasing trend, P<0.05

10 Species analyzed: Tundra Swan, Greater White-fronted Goose, Snow Goose, Ross’s Goose, Wood Duck, Mallard, Cinnamon Teal, Northern Shoveler, Northern Pintail, Green-winged Teal

Diving Ducks

Canvasback Lesser Scaup BuffleheadHooded

MerganserCommon

Merganser Ruddy Duck

+++ +++ +++ +++ + +++

9 Species analyzed: Canvasback, Ring-necked Duck, Lesser Scaup, Bufflehead, Hooded Merganser, Common Merganser, Ruddy Duck

Wate

rfowl (

19)

Shoreb

irds,

Herons

, and

othe

r wate

r bird

s (19

)

Ripari

an/w

oodl

and b

irds (

21)

Grassla

nd bi

rds (

14)

-60%

-40%

-20%

0%

20%

40%

60%

80%

% increasing

% decreasing

Trends from CV CBC data (1976-2010)

Shorebirds

Black-necked Stilt American Avocet Greater Yellowlegs DunlinLong-billed Dowitcher

+++ ++ +++ ++ ++

7 Species analyzed: Black-necked Stilt, American Avocet, Greater Yellowlegs, Long-billed Curlew, Dunlin, Least Sandpiper, Long-billed Dowitcher

Herons and other waterbirds

American Bittern Great Egret

Snowy Egret Cattle Egret

Black-crowned

Night-Heron

White-faced Ibis

Eared Grebe

American Coot

- - - +++ +++ +++ ++ +++ +++ +

12 Species analyzed: American Bittern, Great Blue Heron, Great Egret, Snowy Egret, Cattle Egret, Green Heron, Black-crowned Night-Heron, White-faced Ibis, Pied-billed Grebe, Eared Grebe, Western/Clark’s Grebe, American Coot

Wate

rfowl (

19)

Shoreb

irds,

Herons

, and

othe

r wate

r bird

s (19

)

Ripari

an/w

oodl

and b

irds (

21)

Grassla

nd bi

rds (

14)

-60%

-40%

-20%

0%

20%

40%

60%

80%

% increasing

% decreasing

Trends from CV CBC data (1976-2010)

RIPARIAN/WOODLAND BIRDS

Riparian/Woodland Birds

Red-shouldered Hawk

Nuttall’s Woodpecker Hutton’s Vireo Bushtit Bewick’s Wren

+++ + +++ +++ - - -

21 Species analyzed: Red-shouldered Hawk, Cooper’s/Sharp-shinned Hawk, Nuttall’s Woodpecker, Downy Woodpecker, Northern Flicker, Hutton’s Vireo, Oak Titmouse, Bushtit, White-breasted Nuthatch, Bewick’s Wren, House Wren, Ruby-crowned Kinglet, Hermit Thrush, Yellow-rumped Warbler, Spotted Towhee, California Towhee, Fox Sparrow, Song Sparrow, Lincoln’s Sparrow, White-crowned Sparrow, Golden-crowned Sparrow

House WrenYellow-rumped

Warbler California TowheeLincoln’s Sparrow

White-crowned Sparrow

+++ +++ - +++ - -

Wate

rfowl (

19)

Shoreb

irds,

Herons

, and

othe

r wate

r bird

s (19

)

Ripari

an/w

oodl

and b

irds (

21)

Grassla

nd bi

rds (

14)

-60%

-40%

-20%

0%

20%

40%

60%

80%

% increasing

% decreasing

Trends from CV CBC data (1976-2010)

GRASSLAND BIRDS

Grassland Birds

Ferruginous Hawk

Rough-legged Hawk

American Kestrel

Prairie Falcon

Loggerhead Shrike

American Pipit

Lark Sparrow

Western Meadowlar

k

+++ - - - - - - - - - - - - - - - - -

14 Species analyzed: Ferruginous Hawk, Rough-legged Hawk, Golden Eagle, American Kestrel, Prairie Falcon, Killdeer, Say’s Phoebe, Loggerhead Shrike, Horned Lark, Western Bluebird, American Pipit, Lark Sparrow, Savannah Sparrow, Western Meadowlark

Wate

rfowl (

19)

Shoreb

irds,

Herons

, and

othe

r wate

r bird

s (19

)

Ripari

an/w

oodl

and b

irds (

21)

Grassla

nd bi

rds (

14)

-60%

-40%

-20%

0%

20%

40%

60%

80%

% increasing

% decreasing

Trends from CV CBC data (1976-2010)

Trends from CV BBS data (1966-2006)

Non-grassland Birds (36) Grassland birds (7)

-50%

-40%

-30%

-20%

-10%

0%

10%

20%

30%

% increasing

% decreasing

How important is the CV to the grassland species

in decline?

Grassland Birds

Ferruginous Hawk

Rough-legged Hawk

American Kestrel

Prairie Falcon

Loggerhead Shrike

American Pipit

Lark Sparrow

Western Meadowlar

k

+++ - - - - - - - - - - - - - - - - -

14 Species analyzed: Ferruginous Hawk, Rough-legged Hawk, Golden Eagle, American Kestrel, Prairie Falcon, Killdeer, Say’s Phoebe, Loggerhead Shrike, Horned Lark, Western Bluebird, American Pipit, Lark Sparrow, Savannah Sparrow, Western Meadowlark

American Kestrel Zach Smith

CV = 6% of total

Central Valley Rest of Wtr Range0

20

40

60

80

100

American KestrelB

irds

/100

hrs

Prairie Falcon Phil Robertson

CV = 8% of total

Central Valley Rest of Wtr Range0.0

0.5

1.0

1.5

2.0

2.5

3.0

Prairie FalconBi

rds/

100

hrs

Loggerhead Shrike P. LaTourrette

CV = 4% of total

Central Valley Rest of Wtr Range0

10

20

30

40

Loggerhead ShrikeBi

rds/

100

hrs

American Pipit

J. Ferrante

Central Valley Rest of Wtr Range0

100

200

300

400

500

600

American PipitBi

rds/

100

hrs

CV = 19% of total

Lark Sparrow T. Roach

Central Valley Rest of Wtr Range0

20

40

60

80

100

120

140

160

180

Lark SparrowBi

rds/

100

hrs

CV = 27% of total

Western Meadowlark US FWS

CV = 36% of total

Central Valley Rest of Wtr Range0

200

400

600

800

1000

1200

1400

Western MeadowlarkBi

rds/

100

hrs

California’s Central Valley supports the highest

abundance and diversity of wintering raptors in

the country.

Highest Winter Raptor Abundance

CBC # raptors

1 Mad Island Marsh, TX 879

2 Benicia, CA 735

3 Lincoln, CA 729

4 Rio Cosumnes, CA 655

5 Sacramento, CA 634

Highest Winter Raptor Abundance

CBC # raptors1 Mad Island Marsh, TX 8792 Benicia, CA 7353 Lincoln, CA 7294 Rio Cosumnes, CA 6555 Sacramento, CA 6346 Pt. Reyes, CA 6217 Lacassine NWR, LA 5548 Stockton, CA 4839 Attwater NWR, TX 477

10 Cypress Crk, TX 47311 Los Banos, CA 42412 La Sal Vieja, TX 419

Highest Winter Raptor Abundance

Ave/Count Circle Ave/100 pty hrs0

50

100

150

200

250

300

350

CA Central Valley

TX/LA Coastal Plain

All Other

High Winter Raptor Species Richness

Species/Circle Range

CA Central Valley 12.1 7.8 - 13.9

TX/LA Coastal Plain 11.4 7.8 - 15.5