Weather Surveillance Radar Reveals Bird Response to the Migratory Bird Habitat Initiative
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Natural Resources Conservation Service
Weather Surveillance Radar Reveals
CEAP Conservation Insight
Conservation Effects Assessment Project Bird Response to the Migratory Bird
December 2014
Habitat Initiative
Summary Findings (TX, LA, AR, MO, and MS; USDA
Background
NRCS 2012). Water levels at MBHI
In response to the 2010 Deepwater Hori- Extensive coastal wetlands along the
zon oil spill, NRCS implemented the
sites were managed for shallow water
northern Gulf of Mexico coastline and mudflats to create or enhance
Migratory Bird Habitat Initiative (MBHI) serve as habitat for a wide variety of
to provide temporary wetland habitat for seasonal habitat for waterfowl, shore-
resident and migratory waterbirds. birds, and other waterbirds.
migrating and wintering waterfowl,
These wetlands have been significantly
shorebirds, and other birds along the
degraded by human-induced landscape Bird use of MBHI sites prior to en-
northern Gulf of Mexico inland from oil-
alterations, sea level rise associated rollment and management is largely
impacted coastal wetlands.
with climate change, powerful storms, unknown, limiting the usefulness of
Weather surveillance radar was used to and recently by the April 2010 Deep- traditional field survey methods for
assess bird response to MBHI activities. water Horizon oil spill off the Gulf assessing program effectiveness. Re-
Complementary field studies of seasonal Coast. motely-sensed weather surveillance
bird use of southwest Louisiana MBHI radar observations of bird activity can
sites were conducted to ground-truth the provide a comprehensive assessment
larger-scale weather radar assessment.
In response to the oil spill, the Natural
Resources Conservation Service of bird use at numerous sites and, be-
Birds responded positively to MBHI man- (NRCS) implemented the Migratory cause they are archived, provide ob-
agement by exhibiting greater densities Bird Habitat Initiative (MBHI) to pro- servations of bird use of sites prior to
within sites relative to prior years and vide migrating and wintering water- MBHI enrollment.
relative to surrounding non-flooded agri- fowl, shorebirds, and other birds with
cultural lands. Bird density at MBHI sites alternative habitats inland of coastal The national network of weather sur-
was generally greatest during winter. wetlands potentially impacted by the veillance radars (model WSR-88D,
oil spill. Beginning in the fall of 2010, commonly referred to as NEXRAD)
The magnitude of bird response at sites has been used as a tool to study bird
MBHI incentivized landowners to
compared to prior years and concurrent- movements in a variety of settings
flood existing croplands and idle cat-
ly with non-flooded agricultural lands (O’Neal et al. 2010; Buler et al.
fish ponds and to enhance wetland hab-
was generally related to the surrounding 2012a, 2012b). NEXRAD data have
landscape context, such as proximity to
itats on existing Wetlands Reserve Pro-
gram (WRP) sites. MBHI focal areas been used to depict bird distributions
areas of high bird density and landscape
composition. included the Mississippi Alluvial Val-
ley (MAV) and West Gulf Coastal
Greater increases in relative bird use Plain (WGCP) ecoregions due to their
were detected at sites in closer proximity importance to migrating and wintering
to areas of high bird density and emer- waterbirds and their proximity to
gent marsh. coastal wetlands potentially impacted
by the oil spill.
PHOTO: JOHN PITRE, NRCS
Weather radar observations provide
strong evidence that MBHI sites that
Program activities continued through
were inland from coastal wetlands po-
winter and spring 2010/2011 (or longer
tentially impacted by the oil spill provided
wetland habitat used by a variety of
for sites with multi-year contracts).
birds.
Approximately 465,000 acres were
enrolled into the MBHI within the Northern pintails on Vermilion Parish, La.
MAV and WGCP across five states MBHI site, October 2010.
“on the ground” as birds take flight en food availability and waterfowl habi-
masse at the onset of highly- tat carrying capacity estimates at- KLZK
synchronized broad-scale movements, tributable to MBHI. Preliminary find-
such as nocturnal feeding flights of ings of those studies are presented by
wintering waterfowl and migratory Kaminski and Davis (2014). KNQA
flights of landbirds (Buler and Diehl
2009, Buler and Moore 2011, Buler et Assessment Approach
Mississippi
al. 2012a). Along the Gulf Coast dur- Alluvial Valley
Study Area
ing the winter, waterfowl and other
The MBHI was broadly applied
associated species regularly undertake
throughout the MAV and areas of the
sunrise or sunset flights in large
WGCP. However, analysis of bird use West Gulf Coastal
groups between roosting sites— Plain
of MBHI sites using NEXRAD data
usually wetlands and bodies of wa-
is limited to landscapes within 80 km
ter—and feeding habitat such as agri-
of weather radar stations. Two radar
cultural fields (Buler et al. 2012a,
stations in the MAV and two stations
Randall et al. 2011). KLCH
in the WGCP contained sufficient
archived radar data near MBHI sites KHGX
Assessment Partnership
for useful analysis (Fig. 1). Individual
Scientists at the Aeroecology Pro- MBHI tracts near these radars that Figure 1. Locations of MBHI sites (black
were at least 1 acre in size were in- dots) within the effective observation
gram at the University of Delaware
cluded in the assessment. Only Ar- areas (dark grey) of four weather sur-
(UD) and USGS National Wetlands
veillance radars (labeled by name). The
Research Center (NWRC) have ex- kansas sites were within the effective
light grey denotes counties included in
tensive experience using NEXRAD radar detection range for radars within
the MBHI.
radar data in avian ecology studies. In the MAV; therefore MAV sites in
2011, a partnership was formed Mississippi and Missouri were ex-
among NRCS, UD and NWRC to cluded from analysis. Weather surveillance radar data
conduct an assessment of seasonal The assessment team acquired weath-
bird response following MBHI imple- Timing and intensity of water level er radar data collected during time
mentation. This partnership involved manipulation varied somewhat among periods associated with migrating and
analysis of available NEXRAD states to meet local waterbird habitat wintering bird movements (August 15
weather surveillance data applicable objectives. Table 1 shows the season –May 31) for the years 2008–2011 at
to MBHI sites as well as detailed field dates used for this assessment. KLCH, KHGX, KLZK, and KNQA
studies of sites within NEXRAD ra- from the National Climatic Data Cen-
dar coverage to verify remotely- Acreage of MBHI sites included in ter data archive (http://www.ncdc.
sensed bird reflectivity data and clas- the analysis is shown in Table 2. Vari- noaa.gov/nexradinv/). Radars measure
sify bird use data by season and types ability in the area analyzed is due to reflectivity (Z) in the form of returned
of birds observed. differences in the amount of area en- radiation, and the density of birds on
rolled between seasons and differ- the ground is positively correlated to
ences in the effective detection range radar reflectivity at the onset of flight
This assessment partnership was sup- of the radar among sampling days.
ported by the Wildlife Component of exodus (Buler and Diehl 2009, Buler
Overall, approximately 10 percent of et al. 2012a). Radar data from nights
the Conservation Effects Assessment the area enrolled in MBHI within Ar-
Project (CEAP), and this conservation with no discernible contamination
kansas (MAV) and 15 percent of the
insight summarizes the findings pro- enrolled area in Texas and Louisiana
duced. Additional details are available Table 2. Total area (acres) of managed
(WGCP) were included in the assess- MBHI sites within the radar detection
in Sieges et al. (2014) and the final ment. range included in the assessment.
University of Delaware and USGS
NWRC project reports available on Table 1. Season dates used for assess- Region
the CEAP website (Buler et al. 2013, ment of waterbird habitat. WGCP MAV
Barrow et al. 2013).
Season Dates LA TX AR
Season
Under a separate partnership with
Fall October 1–October 31 Fall 15,925 19,105 6,303
NRCS, a team of scientists led by
Mississippi State University is con- Winter November 1–February 28 Winter 15,078 14,922 6,224
ducting more detailed and intensive
field studies to quantify waterbird Spring March 1–March 31 Spring 1,294 15,814 —
2
from precipitation or other clutter tion of imagery (Fig. 2). This thresh- the 2006 National Land Cover Da-
were used to produce sample poly- old was used to determine the extent taset (http://www.mrlc.gov/). Percent
gons representing bird activity for of flooding within MBHI areas. of surrounding agricultural land that
overlaying onto land cover maps was flooded versus non-flooded was
within a Geographic Information Sys- Change in soil wetness from baseline also determined using the soil wetness
tem (GIS). Adjustments were made to years (2008-2009 and 2009-2010) to index derived from TM imagery. Cor-
account for sun angle and how birds the management year (2010-2011) in relations between bird response at a
are sampled in the airspace as the ra- fall and winter was also determined. sample of MBHI sites and each sur-
dar beam spreads with range to opti- During the spring of 2011, all TM rounding land cover type at various
mize how radar data represent bird images in the KHGX and KLCH ra- scales (0.3 to 2.8 miles) were assessed
activity in the vicinity of MBHI sites dar ranges were obscured by clouds, to look for patterns between bird re-
(Buler et al. 2013). preventing comparisons of site soil sponse and surrounding land use.
wetness during spring management to
Ground-truthing NEXRAD bird de- the baseline years. Areas of high bird density during
tection baseline years were defined as poly-
To ensure NEXRAD radar data relia- Landscape composition data gons having a seasonal mean reflec-
bly represented birds aloft, the USGS Percent cover of agricultural land, tivity above the 90th percentile. This
assessment team used weather sur- emergent marsh, permanent open wa- effectively identified areas with the
veillance and portable marine radar ter, and forested wetlands surrounding highest bird density that occurred
data, thermal infrared images, and individual radar sample polygons was within each radar-observed area.
visual observations of bird use of se- determined at multiple scales using Some of the identified areas were lo-
lect MBHI sites in southwest Louisi-
ana. By examining seasonal bird use
of MBHI fields in fall, winter, and
spring of 2011-2012, these field stud- Wet
ies enabled the assessment team to
associate NEXRAD radar echoes to
bird species or species group.
To assess diurnal use, the field team
Dry
conducted total area surveys of MBHI
November 10, 2009
sites in the afternoon, collecting data August 25, 2010 October 28, 2010
on bird species composition, abun-
dance, behavior, and habitat use.
0.1
Evening bird use and flight behavior
(i.e., birds landing in, departing from, 0.0 Flooded
circling, or flying over MBHI sites)
Wetness Index (Dry → Wet)
Flooded
was also documented. This field sam- -0.1 Not Flooded
pling captured the onset of evening
flights and spanned the period of col- -0.2 MBHI
Management
lection of the weather radar data ana-
-0.3 Fall
lyzed. Pre- and post-dusk surveys Winter
Spring
were conducted using a portable radar
-0.4
system and a thermal infrared camera.
-0.5
Soil wetness data
The assessment team used remotely- -0.6
sensed Landsat Thematic Mapper
6/1/2008
3/1/2011
3/1/2008
9/1/2008
12/1/2008
3/1/2009
6/1/2009
9/1/2009
12/1/2009
3/1/2010
6/1/2010
9/1/2010
12/1/2010
6/1/2011
9/1/2011
12/1/2011
(TM) data to quantify the extent of
flooding during the MBHI manage-
ment year (2010-2011) and two previ-
ous years via a soil wetness index
Figure 2. Mean soil wetness index values for several MBHI sites (black outlines) de-
(Crist 1985, Huang et al. 2002). In- rived from TM data. Three TM images show temporal variation in soil wetness. Sites
creasing values indicate increasing are completely flooded in the October 2010 image in accordance with MBHI manage-
soil wetness. Index values greater ment. Corresponding mean wetness index values are plotted for the entire study
than -0.05 indicate open surface water period illustrating the fall-winter-spring flooding regime. Shaded bars distinguish the
(flooded soil) based on visual inspec- periods of active management.
3cations where birds are historically mid-winter peak, and KLCH a late
known to concentrate, such as winter- winter peak.
ing waterfowl at Lacassine National
Wildlife Refuge (NWR) and Cameron Overall, bird density at MBHI sites
Prairie NWR, in Louisiana. during the management year for near-
ly all seasons and radars was greater
Data analyses relative to prior years and relative to
To control for potential confounding non-flooded agriculture (NFA) (Table
year effects due to annual fluctuations 3). This is indicated by the mean
Relative bird density (Reflectivity in Z)
in overall bird populations, reflectivi- standardized reflectivity and the ratio
ty values during a given year were of reflectivity relative to prior years
divided by the area-weighted mean or NFA having values greater than
reflectivity of all radar sample poly- one. The majority of MBHI sites ex-
gons dominated (>75% of area) by hibited greater bird use relative to
non-flooded agricultural lands during NFA within the management year and
that same year for each radar and sea- relative to prior years for fall and win-
son combination. Thus, reflectivity ter, but not during spring. Exceptions
was standardized to be the ratio of for a majority increase in bird use
observed reflectivity relative to con- relative to NFA in the management
current reflectivity at unmanaged year by radar included KNQA during
fields and serve as an indicator of bird the fall and KLCH and KHGX in the
response to MBHI management. A spring. Additionally, a majority of the
value greater than one indicates that area around KHGX during the spring
bird density was greater than concur- did not increase in bird use relative to
rent bird density at unflooded agricul- prior years.
tural fields. Standardized reflectivity
was used as the response variable for The greatest increases in the amount
modeling bird use of MBHI areas and extent of reflectivity (bird use)
within the management year. relative to prior years occurred during
Figure 3. Daily mean relative bird densi- winter in Louisiana (KLCH) and east-
Bird response to MBHI activities was ty during the management year at MBHI ernmost Arkansas (KNQA) sites and
also assessed by comparing standard- sites for each radar. Shaded bars distin- during fall in Texas (KHGX) and
ized bird density in the two years pri- guish the periods of active management. western Arkansas (KLZK) sites
or to management to bird density dur-
ing the active management year (2010 Table 3. Means for measures of soil wetness and relative bird density (i.e., standard
reflectivity) during the year of active management and compared to prior years with-
-2011). The proportion of MBHI are- out management. Sample size is the number of sample MBHI polygons assessed.
as that showed increases in mean wet-
ness, mean reflectivity during the West Gulf Coastal Mississippi Alluvial
Plain Valley
management year, and mean reflectiv-
KLCH KHGX KLZK KNQA
ity relative to prior years was calcu-
Variables Mean Mean Mean Mean
lated to understand how management
Fall
practices influenced the assessed area. n = 2743 n =1616 n =534 n =171
Soil wetness index during management year -0.14 -0.13 -0.22 -0.19
Findings Change in soil wetness index from prior years -0.02 -0.01 -0.09 -0.08
Bird response Reflectivity relative to non-flooded agriculture 2.33 2.60 2.66 0.91
Relative bird density at MBHI sites, Reflectivity relative to prior years 2.7 9.44 7.82 1.21
as depicted by daily mean radar re- Winter n = 2921 n =1531 n =534 n =148
flectivity, varied considerably among
radars throughout the management Soil wetness index during management year -0.09 -0.07 -0.13 -0.05
periods, with the KLZK and KLCH Change in soil wetness index from prior years 0.00 0.01 -0.03 0.03
radars showing much higher reflectiv- Reflectivity relative to non-flooded agriculture 1703.38 5.06 29.86 1.93
ity overall (Fig. 3). For all radars, re- Reflectivity relative to prior years 10.27 5.71 1.64 2.80
flectivity peaked during winter man- Spring n = 206 n =1603 — —
agement, although the timing differed
among radars: KHGX showed an ear- Reflectivity relative to non-flooded agriculture 2.45 0.24 n/a n/a
ly winter peak, KLZK and KNQA a Reflectivity relative to prior years 2.21 1.97 n/a n/a
4spring by ducks, geese, wading birds,
and landbirds.
Soil wetness
Mean soil wetness index during the
management year nearly always indi-
cated non-flooded soil conditions on
average (values < -0.05) at sites dur-
ing fall and winter. However, there
were usually areas that were flooded
within MBHI site boundaries even if
the entire site was not flooded (Fig 4).
The change in mean soil wetness in-
dex from prior years in the fall was
negative, indicating dryer soil in the
management year. However, it was
slightly positive for the KHGX and
KNQA radars in winter. Soil wetness
was greatest during winter, though
only slightly more than half of the
MBHI area was considered flooded
with surface water in the WGCP.
During winter in the MAV, nearly all
of the MBHI area was flooded at
Figure 4. Images of remotely-sensed soil wetness and radar reflectivity data at a KNQA, but less than a quarter was
representative complex of MBHI sites (outlined). As depicted by TM imagery from flooded at KLZK. The lower soil wet-
single dates, MBHI sites are mostly flooded by surface water during the management ness during fall is consistent with fall
year (top right panel) and relatively dry during a prior year (top left panel). Mean
standardized radar reflectivity at the onset of evening flight (i.e., relative bird densi- moist soil management for shore-
ty) is greater within and around MBHI sites during the winter of the management year birds, and the higher soil wetness in
(bottom right panel) than during the previous two winters (bottom left panel). winter is consistent with open water
management for wintering waterfowl.
(Table 3). The greatest use by birds of when the majority of shorebirds had
MBHI managed sites relative to NFA already passed through the region and Bird density increased at MBHI sites
occurred during winter at all radars. before the arrival of most migratory despite detection of little or no in-
The greatest responses to MBHI man- waterfowl. Thus, NEXRAD detected creases in soil wetness. The remotely-
agement both within and between bird density at MBHI sites was con- sensed data used to calculate soil wet-
years, across all radars and seasons, sidered lower during the fall. Howev- ness indices may not have been ro-
occurred at Louisiana sites during the er, field surveys of MBHI sites in bust enough to detect season-long
winter. Here, over 90 percent of south Louisiana (near KLCH) detect- surface water conditions. Few usable
MBHI area had increased bird use ed shorebirds and other bird taxa us- TM images were available for each
relative to previous years and NFA ing MBHI sites during all seasons radar and season with which to calcu-
such that the average bird density was (Fig 5). late the index. Additionally, the as-
over 10 times that from previous sessment team had no information
years and over 1,700 times that of The combined approach of using di- about the extent of flooding within
NFA. An example of MBHI sites il- rect visual counts, portable marine individual properties. Thus, a land-
lustrating strong bird response during radar data, and a thermal imaging owner’s contract may require flood-
the management year relative to prior camera for ground-truthing NEXRAD ing on only a portion of a property,
years is depicted in Fig. 4. data was valuable for classifying and whereas this analysis may have in-
quantifying migrating and wintering cluded the whole property boundary.
Different groups of birds migrate bird use of MBHI sites in southwest Moreover, drought conditions, re-
through the area at different times of Louisiana. Results of direct observa- stricted water supplies, or other cir-
the year, with landbirds and shore- tions indicate that MBHI fields pro- cumstances may have prevented land-
birds passing through first in spring vided diurnal foraging habitat for owners from complying fully with
and fall followed by waterfowl that shorebirds during fall migration and their contracts. Arkansas was under
often stay through the winter. Fall for multiple taxa in winter and spring. drought conditions in 2010. Thus,
management for this assessment oc- MBHI fields were also used as diur- these conditions complicated quantifi-
curred during the month of October, nal resting sites in fall, winter, and cation of changes in site wetness (i.e.,
520 20 the landscape had greater bird
Ducks Geese
density.
33.3
15 15 In the MAV, bird densities at
MBHI sites were positively asso-
Density (birds/ha)
Density (birds/ha)
10 10
ciated with forested wetlands in
the surrounding area. Field sur-
5 5
veys revealed this relationship
was likely due to large numbers
of spring and fall migrating land-
0 0
birds typically associated with
Au . 15
Se . 29
Se . 12
Oc . 26
De 21
Fe . 13
Ma . 27
Ma 23
Ma y 7
Au . 15
Se . 29
Se . 12
Oc . 26
De 21
Fe . 13
Ma . 27
Oc . 10
No 24
Ja 19
Ja 16
Fe . 30
No v. 7
Oc . 10
No 24
Ja 19
Ja 16
Fe . 30
Ma 23
Ma y 7
De c. 5
Ma . 12
Ap 26
Ap r. 9
1
No v. 7
1
Ja n. 2
De c. 5
Ma . 12
Ap 26
Ap r. 9
Ja n. 2
y2
y2
forested habitats.
v.
r.
v.
c.
n.
c.
n.
r.
t.
r.
t.
r.
g
g
p
p
b
b
g
g
p
p
b
b
n
r
n
r
t
t
Au
Au
20 20
Shorebirds Waders Proximity to bird concentrations
Within the WGCP during fall and
15 15
winter, the only variable that exhibit-
Density (birds/ha)
Density (birds/ha)
ed a consistent relationship with bird
10 10 density among the two radars was
proximity to high bird density area.
5 5 Established areas of high waterbird
densities along with the tendency of
0 0 waterbirds to form traditional large
roosting flocks are two likely reasons
Au . 15
Se . 29
Se . 12
Oc . 26
De 21
Fe . 13
Ma . 27
Au . 15
Se . 29
Se . 12
Oc . 26
De 21
Fe . 13
Ma . 27
Oc . 10
No 24
Ja 19
Ja 16
Fe . 30
Ma 23
Ma y 7
No v. 7
Oc . 10
No 24
Ja 19
Ja 16
Fe . 30
Ma 23
Ma y 7
No v. 7
1
De c. 5
Ap r. 9
1
Ja n. 2
Ma . 12
Ap 26
De c. 5
Ap r. 9
Ja n. 2
Ma . 12
Ap 26
y2
y2
v.
v.
c.
n.
r.
c.
n.
r.
t.
r.
t.
r.
g
g
p
p
b
b
g
g
p
p
b
b
n
r
n
r
t
t
Au
Au
for greater increases observed at sites
50
20 close to high bird density areas. With-
Landbirds Seabirds / Waterbirds
40
30
in Louisiana, radar observations indi-
20 15
Seabirds
Waterbirds
cate birds are concentrated in marsh
and agricultural areas within and
Density (birds/ha)
Density (birds/ha)
15
10
around Lacassine and Cameron Prai-
10
rie National Wildlife Refuges and the
White Lake Wetlands Conservation
5
5 Area. These areas are well-known
roosting areas for wintering water-
0 0
fowl (Link et al. 2011). These find-
Au . 15
Se . 29
Se . 12
Oc . 26
De 21
Ja 19
Au . 15
Se . 29
Se . 12
Oc . 26
De 21
Ja 16
Fe . 30
Fe . 13
Ma . 27
Ma 23
Ma y 7
Ja 19
Ja 16
Fe . 30
Fe . 13
Ma . 27
1
Ma 23
Ma y 7
1
Oc . 10
No 24
No v. 7
De c. 5
Ja n. 2
Ma . 12
Ap 26
Oc . 10
No 24
No v. 7
Ap r. 9
De c. 5
Ja n. 2
Ma . 12
Ap 26
Ap r. 9
y2
y2
ings support the idea that birds use
v.
v.
c.
n.
r.
c.
n.
r.
t.
r.
t.
r.
g
g
p
p
g
g
p
p
n
b
b
r
n
b
b
r
t
t
Au
Au
certain areas consistently during the
Figure 5. Biweekly bird use of MBHI fields (# of birds/ha) detected via ground- winter and that these areas may be
truthing surveys by taxa: ducks, geese, shorebirds, wading birds, landbirds, seabirds, important predictors of waterbird ac-
and waterbirds. tivity.
Importance of surrounding wetlands
flooding) during the management the management year. Notable rela- Regional habitat differences associat-
year. Management activities associat- tionships detected include: ed with emergent marsh influenced
ed with the MBHI may have provided At both WGCP radars in fall and
observed bird response. The im-
stopover habitat for migrating shore- all radars in winter, the most im- portance of emergent marsh in pre-
birds, even where surface water was portant variable in explaining dicting bird densities was apparent in
lacking. Landowners may have been standardized bird density within the winter with the finding that in-
unable to maintain winter flooding at the management year was prox- creased bird densities at MBHI sites
such a depth that would benefit water- imity to areas of high bird densi- in the WGCP region were related to
fowl, but any water on the fields like- ty, such that bird density in- higher amounts of emergent marsh in
ly benefited shorebirds because they creased in closer proximity to the surrounding landscape. Emergent
are known to identify and use moist high bird density areas. marshes are often part of large and
soils within days of being saturated. Within the WGCP, bird density
diverse wetland complexes that sup-
was positively related to greater port a diversity of birds (Brown and
Landscape attributes amounts of emergent marsh in the Dinsmore 1986). Wetland complexes
The assessment team evaluated vari- surrounding area. in various stages of succession have
ous landscape variables that may help In the WGCP, MBHI areas with
proven to be the most beneficial to
explain observed bird response during more non-flooded agriculture in waterbirds (Fredrickson and Reid
61986, Kaminski et al. 2006, Van der waterfowl may have varied based on clustered into wetland mosaics that
Valk 2000, Webb et al. 2010, Pearse the land use prior to flooding. more closely resemble natural wetland
et al. 2012). complexes (Brown and Dinsmore
Some fields were pastures (15% in 1986, Pearce et al. 2012). With pre-
MAV and forested wetlands the MAV, 20% in the WCGP) during dicted changing climactic conditions,
Field surveys conducted around sun- the management year and may not providing habitat for migratory birds
set (i.e., close to when NEXRAD have provided much forage in the in the MAV and WGCP will continue
sampled the airspace over MBHI form of wetland plant seed during the to be important for all stakeholders,
sites) revealed a mix of landbirds, first year of the program. Rice seed particularly with the knowledge that
shorebirds, and early waterfowl en- persists longer in wetlands than other migration is a limiting factor for
gaging in evening migratory flights seeds associated with crop harvest shorebirds and waterfowl (Alisauskas
during October. This mix of evening waste, thereby potentially increasing and Ankney 1992, Morrison et al.
flight activity from different bird available forage for waterbirds com- 2007).
groups may in part explain why less pared to other flooded crops (Nelms
variability in fall bird density was and Twedt 1996, Stafford et al. 2006). References
explained by modeling in both the
Alisauskas, R.T., and C.D. Ankney. 1992.
MAV and WGCP regions compared However, only 20% of the MBHI The cost of egg laying and its relation-
to the winter. sites in the MAV in this study were ship to nutrient reserves in waterfowl.
rice fields compared to 40% in the Pages 30-61 in B.D.J. Batt, A.D. Afton,
Since migrating landbirds contributed WGCP, which may account for great- M.G. Anderson, C.D. Ankney, D.H.
to the reflectivity detected in the er positive changes in reflectivity val- Johnson, J.A. Kadlec, and G.L.Krapu,
editors. Ecology and Management of
MAV in the fall, bird densities at ues in the WCGP. Although water- Breeding Waterfowl. University of Min-
MBHI sites were positively associat- fowl will feed on non-flooded waste nesota Press, Minneapolis, MN.
ed with forested wetlands. Areas with grain, flooding rice fields increases Barrow, W.C., M.J. Baldwin, L.A. Randall, J.
more forested wetlands in the sur- habitat for waterfowl and other water- Pitre, and K.J. Dudley. 2013. Application
rounding area had higher bird densi- birds (Elphick and Oring 1998). of ground-truth for classification and
quantification of bird movements on
ties during the management year, Migratory Bird Habitat Initiative sites in
likely indicating contamination of the Because portions of the MAV and southwest Louisiana. U.S. Geological
airspace over areas by landbirds initi- WGCP have been farmed for rice Survey National Wetlands Research Cen-
ating migration from adjacent forest- over the past 150 years (Hobaugh et ter Final Report to USDA NRCS Conser-
ed habitats, which are known to har- al. 1989), waterbirds may be depend- vation Effects Assessment Project http://
www.nrcs.usda.gov/Internet/
bor high densities of migrating land- ent on flooded agricultural fields for FSE_DOCUMENTS/
birds (Buler and Moore 2011). Addi- wintering habitat, in which case the stelprdb1247057.pdf.
tionally, some waterfowl such as MBHI provided valuable areas that Brown, M., and J.J. Dinsmore. 1986. Impli-
green-winged teal, mallards and landowners may not have flooded in a cations of marsh size and isolation for
hooded mergansers use forested wet- drought year. marsh bird management. Journal of
Wildlife Management 50:392–397.
lands in the MAV throughout the
Buler, J.J., and R.H. Diehl. 2009. Quantify-
spring and fall (Heitmeyer 1985). Soil Conclusion ing bird density during migratory stopo-
wetness data also indicate that many ver using weather surveillance radar.
In the wake of a major environmental
sites in the MAV were not actually IEEE Transactions on Geoscience and
disaster, the MBHI provided water- Remote Sensing 47:2741–2751.
flooded in October and that drier sites
birds with temporary wetland habitats Buler, J.J., and F.R. Moore. 2011. Migrant–
were weakly associated with a greater
by flooding agricultural fields within habitat relationships during stopover
increase in bird density in the man- along an ecological barrier: extrinsic
the MAV and WGCP regions. In-
agement year relative to prior years. constraints and conservation implica-
creases in bird densities were detected
During fall management in the MAV, tions. Journal of Ornithology 152:101–
on the majority of MBHI sites during 112.
sites were drier than those in the Gulf
migration and wintering periods for Buler, J.J., L.A. Randall, J.P. Fleskes, W.C.
and observed bird densities may re-
waterfowl and shorebirds. The great- Barrow, T. Bogart, and D. Kluver. 2012a.
flect shorebirds using drier mudflat Mapping wintering waterfowl distribu-
est relative responses by birds to
sites or, again, landbirds (blackbirds tions using weather surveillance radar.
MBHI sites occurred in the WGCP
en route to their roosts or neotropical PloS One 7:e41571.
during the winter management period
migrants departing the nearby forest- Buler, J.J., W. Barrow Jr., and L. Randall.
at sites closer to areas of high bird 2012b. Wintering Waterfowl Respond to
ed wetlands) utilizing the landscape
density and with more emergent Wetlands Reserve Program Lands in
adjacent to the sites.
marsh in the surrounding landscape. California’s Central Valley. USDA
NRCS CEAP Conservation Insight.
Influence of prior land use Bird use of managed lands may be http://www.nrcs.usda.gov/Internet/
The attractiveness of MBHI sites to maximized if future enrollments are FSE_DOCUMENTS/
stelprdb1048508.pdf.
7The Conservation Effects Assessment Pro-
Buler, J.J., M.L. Sieges, and J.A. Smolinsky. siana. Waterbirds 34:422–428.
ject: Translating Science into Practice
2013. Assessment of bird response to the Morrison, R.I.G., N.C. Davidson, and J.R.
NRCS Migratory Bird Habitat Initiative Wilson. 2007. Survival of the fattest: The Conservation Effects Assessment
using Weather Surveillance Radar. Uni- body stores on migration and survival in Project (CEAP) is a multi-agency effort to
versity of Delaware Aeroecology Pro- red knots Calidris canutus islandica. build the science base for conservation.
gram, Final Report to USDA NRCS Journal of Avian Biology 38:479–487.
Project findings will help to guide USDA
Conservation Effects Assessment Project O’Neal1, B.J., J.D. Stafford, and R.P. Larkin.
conservation policy and program develop-
http://www.nrcs.usda.gov/Internet/ 2010. Waterfowl on weather radar: ap-
ment and help farmers and ranchers make
FSE_DOCUMENTS/ plying ground-truth to classify and quan-
informed conservation choices.
stelprdb1119393.pdf. tify bird movements. Journal of Field
Crist, E.P. 1985. A TM tasseled cap equiva- Ornithology 81:71–82. One of CEAP’s objectives is to quantify the
lent transformation for reflectance factor Nelms, C.O. and D.J. Twedt. 1996. Seed environmental benefits of conservation
data. Remote Sensing of Environment deterioration in flooded agricultural practices for reporting at the national and
17:301–306. fields during winter. Wildlife Society regional levels. Because fish and wildlife
Elphick, C.S., and L.W. Oring. 1998. Winter Bulletin 24:85–88. are affected by conservation actions taken
management of Californian rice fields for Pearse, A.T., R.M. Kaminski, K.J. Reinecke, on a variety of landscapes, the wildlife na-
waterbirds. Journal of Applied Ecology and S.J. Dinsmore. 2012. Local and land-
tional assessment draws on and comple-
35:95–108. scape associations between wintering
ments the national assessments for
Frederickson, L.H., and F.A. Reid. 1986. dabbling ducks and wetland complexes
cropland, wetlands, and grazing lands. The
Wetland and riparian habitats: a nongame in Mississippi. Wetlands 32:859–869.
wildlife national assessment works through
management overview. Pages 59–96 in Randall, L.A., R.H. Diehl, B.C. Wilson,
numerous partnerships to support relevant
J.B. Hale, L.B. Best, and R.L. Clawson, W.C. Barrow, and C.W. Jeske. 2011.
studies and focuses on regional scientific
editors. Management of Nongame Wild- Potential use of weather radar to study
priorities.
life in the Midwest: A Developing Art. movements of wintering waterfowl. The
The Wildlife Society, Grand Rapids, MI. Journal of Wildlife Management 75:1324 This assessment was conducted through a
Heitmeyer, M.E. 1985. Wintering strategies –1329. partnership among NRCS, the University of
of female mallards related to dynamics of Sieges, M.L., J.J. Buler, J. Smolinsky, W. Delaware (UD) Aeroecology Program, and
lowland hardwood wetlands in the upper Barrow, Jr., M. Baldwin, and L. Randall.
the USGS National Wetlands Research
Mississippi Delta. Ph.D. dissertation, 2014. Assessment of bird response to
Center. Primary investigators on this pro-
University of Missouri, Columbia, MO. Migratory Bird Habitat Initiative man-
ject were Jeffery Buler and Mason Sieges
Hobaugh, W.C., C.D. Stutzenbaker, and E.L. aged wetlands using weather surveillance
(UD) and Wylie Barrow, Mike Baldwin and
Flickinger. 1989. The rice prairies. Pages radar. Southeastern Naturalist. 13:G36–
Lori Randall (USGS).
367-383 in L.M. Smith, R.L. Pederson, G65.
and R.M. Kaminski, editors. Habitat Stafford, J.D., R.M. Kaminski, K.J. For more information: www.nrcs.usda.gov/
Management for Migrating and Winter- Reinecke, and S.W. Manley. 2006. technical/NRI/ceap/, or contact Charlie Rewa
ing Waterfowl in North America. Texas Waste rice for waterfowl in the Missis- at charles.rewa@wdc.usda.gov.
Technical University Press, Lubbock, sippi Alluvial Valley. Journal of Wildlife
TX. Management 70:61–69.
Huang, C., B. Wylie, L. Yang, C. Homer, Webb, E.B., L.M. Smith, M.P. Vrtiska, and
and G. Zylstra. 2002. Derivation of a T.G. Lagrange. 2010. Community struc-
tasselled cap transformation based on ture of wetland birds during spring mi-
Landsat 7 at-satellite reflectance. Interna- gration through the Rainwater Basin.
tional Journal of Remote Sensing Journal of Wildlife Management 74:765–
23:1741–1748. 777.
Kaminski, M.R., G.A. Baldassarre, and A.T.
Pearse. 2006. Waterbird responses to
hydrological management of wetlands
reserve program habitats in New York.
Wildlife Society Bulletin 34:921–926.
Kaminski, R.M., J.B. Davis. 2014. Evalua- Suggested Citation:
tion of the migratory bird habitat initia-
tive: Report of findings. Forest and Wild- Natural Resources Conservation Service. 2014.
life Research Center, Research Bulletin Weather Surveillance Radar Reveals Bird
WF391, Mississippi State University. 24 Response to the Migratory Bird Habitat
pp. Initiative. Conservation Effects Assessment
Link, P.T., A.D. Afton, R.R. Cox, and B.E. Project (CEAP) Conservation Insight.
Davis. 2011. Daily movements of female
www.nrcs.usda.gov/technical/NRI/ceap/.
mallards wintering in southwestern Loui-
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age,
disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs,
reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all pro-
grams.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should
contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination write to USDA, Director, Office of Civil Rights,
1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportuni-
ty provider and employer.
8You can also read
