CVPIA Refuge Biological 
0

100,000200,000300,000400,000500,000600,000700,000800,000

Incremental Level 4: 130,000 AF 

Acre Feet of Water 

Defining Level 2 and Level 

Refuge Water Supply

Full Level 2: 422,000 AF 

(Incremental L-4 requires additional 15AF for water losses – approx. 10%.)
CVPIA Refuge Biological B

• Year-around water supplies

• Long-term management planning• Accurate habitat management evalu• Water for on-refuge restoration pro• Increased hunting/birding opportun• Increase in diversity of habitat and 

species use
Year-Round Habitat Nee

Early Fall HabitatMid-Winter Maintenance FlowsLate Winter Staging Habitat

Spring Riparian HabitatSpring/Summer IrrigationsSpring/Summer Brood Habitat

Primary Fall Flood-Up

AugustSeptemberOctoberNovemberDecemberJanuaryFebruaryMarchAprilMayJuneJuly
Early Fall Habitat

Grasslan

Grasslan

typical m

typical m

numbers 

numbers 

Benefit to early migrants such as whitefronted geese and northern pintails 

May be only quality habitat available in 

Valley
Since CVPIA, a dramatic increase 

in sandhill crane use at Pixley 

NWR:

• 200 in 1992• 2,000 in 1993• 5,100 in 2001• 7,000 in 2008

Early F

Tule Elk, San Luis N
Early Fall Habitat

• Pixley sandhill crane use increased from 

to 7,000 in 2008- - due, in part, to lack oavailable habitat in the southern San Joa
Early Fall Habitat

• Grasslands - - An increase of 3,000 acres of 

early fall habitat :

Shorebird bird-use day increases of 

49% from 1992 to 1994

Recognized WHSRN area of 

international importance to shorebirds
Ma

Sacramento NWRMajor cholera outbreaks in 1991 and 1992...only one major outbreak since CVPIA passed
Merced NWR – Ross’ Geese fattening 

up in March and April before the long flight north

L

St

p
Spring R

Kern NWR - - Great blue heron rookery established in 199835 nests counted in 2006Area also utilized by egrets, cormorants and night-herons

Vital to N

and colo
Spri

d P

Grasslands: yearly irrigated acreage of swamp timothy1991-1992 : 4,000 acres 1993-today: approx. 26,000 acres annuallyA doubling of plant biomass A doubling of plant biomass Reduction in salts
Improv

breeding 

Spr

Summ

H

Cinnamon Teal Broods, Delevan NWR
Spring and Su

Breeding H

Kern NWR - Tri-colored 

nest success improve
• Colusa NWR - Increase in habitat 

available for species of concern such as the western pond turtle and the giant garter snake

Spr

Summe

H
The Return of the White-fa
Populations began a 

steady decline in the 

late 1970’s. 

By 1990 had become 

“species of special 

concern”.

The Return of the White The Return of the White-faced Ibis faced Ibis
CV

CV

pr

pr

sp

sp

ne

ne

The Return of the White The Return of the White-faced Ibis faced Ibis
• Sutter NWR

– 1991: 100 birds to 1,000 in 2000, 7,00

2000: 1,000 and 15,000 in 2002

• Kern NWR

– An increase from 50 birds in 1993, to 5

2001, to 17,000 in 2005

The Return of the White The Return of the White-faced Ibis faced Ibis
Kern National Wildlife R
Kern National Wildlife R

• Established in 1964• Helps offset the loss of Buena Vista a

Lakes 

• 10,600 total acres (6,500 acres of man

wetlands)

• No historical firm water supplies

– Surplus State Water supply– Floodwater flows– Groundwater Wells
Kern National Wildlife R
Kern NWR Habitat Ben

• 2004 : First year that all wetland habi

flooded

• CVPIA supplies provide make deep w

habitat available for the first time

• An increase in tri-colored blackbirds 

the late 1990’s – 21,000 in 2003

• Multiple food plant irrigations most y• Improved water quality with flow-tho

maintenance water
Kern NWR Ibis Numb

1993: 50 2001: 5,6002006: 15,0002008: 900
Kern NWR Water Sup

• Incremental Level 4 Water Supply 

– CVPIA Allocation: 15,050 acre-feet– First Capable of receiving it in 2003 – Amt. Delivered 2006: 11,523 acre-fee– Amt. Delivered 2007: 7,538 acre-feet– Amt Delivered 2008: 4,022 acre-feet
Kern NWR 2006 vs. 

• Public Use: 

– Down 1,000 hunter-days– Lower quality of experience on auto tou– Important for public to see

• Irrigations:

– Zero irrigations in 1,100 acre unit– Reduced irrigations in 1,200 acre unit on – Results in marginal vs robust seed produ

• Lack of diversity• Ex: No watergrass
Kern NWR 2006 vs. 2

• Irrigations:

– Zero irrigations in 1,100 acre unit– Reduced irrigations in 1,200 acre unit on – Results in marginal vs robust seed produ

• Lack of diversity• No Watergrass, Ammania or Burhead 

usage dropped the past two years
Kern NWR 2006 vs. 2

• Lack of Spring and Summer Wat

– Drastically reduced broods (teal an

redheads)...and those nests that sursuccessful to fledging

– No late spring shorebird habitat ava– Tri-Colored Blackbird use down fr

21,000 in 2003 to zero in 2008
Kern NWR 2006 vs. 

• Great Blue Heron rookery nest peake

53 nest, 19 in 2008

• Water quality impacts

– No “flow-through” circulation flows in w

• recirculation of salts• detrimental to soil and vegetation
Kern NWR

• Recent impacts felt by Kern simi

most CVPIA refuges

• Critical to secure and deliver reli

timely Full Level 4 supplies on a basis.