Land Surface Phenology preferences of yellow-billed cuckoo mapped over a
decade: where are the hot spots and why?
Proposal to the SJV by Cynthia S.A. Wallace and Miguel Villarreal
II. Project Details
Project Need: This project will help land managers understand which areas within yellow-billed
cuckoo habitat are critically important for nesting. These areas can potentially be prioritized for
conservation or used to guide restoration of marginal habitat.
Project Location: The study site is the region spanning southeastern Arizona and northern Sonora,
Mexico region (Figure 1); the proposed field work is within the bi-national Santa Cruz river
watershed. We propose to revisit 11 transects along the Santa Cruz River riparian corridor where we
conducted both general avian and yellow-billed cuckoo surveys in 2012 and 2013 (Figure 2). These
sites are on a mixture of private and public lands (i.e. Tumacacori National Historical Park) that
represent a range of riparian vegetation types and conditions. The survey transects are co-located with
highly detailed vegetation transects that describe composition, structure and patterns of recent and
historical riparian vegetation on the Santa Cruz River (Villarreal et al. 2012).
Background: The yellow-billed cuckoo (Coccycus americanus occidentalis) is a neo-tropical migrant
bird that travels from Central and South America into the southwestern United States during the
summer to nest. In the western United States, favored riparian forest and woodland nesting habitat of
this threatened species has declined over the past century, due primarily to human activities and
associated water demands.
In a previous study (Wallace et al., 2013), we mapped yellow-billed cuckoo habitat in the state of
Arizona using the temporal greenness dynamics of the landscape, or the landscape phenology (Figure
3). Landscape phenometrics were derived from Advanced Very High Resolution Radiometer
(AVHRR) 1 kilometer resolution bi-weekly time-composite satellite Normalized Difference
Vegetation Index (NDVI) composite data for 1998 and 1999 using Fourier harmonic analysis to
analyze the waveform of the annual NDVI profile at each pixel. Field data were obtained from a
comprehensive state-wide survey data conducted in 1998 and 1999. To create the models, we coupled
the 1998 field data of cuckoo presence or absence and points sampling riparian and cottonwoodwillow vegetation types with the 1998 satellite phenometrics. Models were tested using field and
satellite data collected in 1999.
The models reveal that cuckoos prefer areas that experience peak greenness 29 days later, are 36%
more dynamic and slightly (< 1%) more productive than their average cottonwood–willow habitat.
The results support a scenario in which cuckoos migrate northwards, following the greening of
riparian corridors and surrounding landscapes in response to monsoon precipitation, but then select
nesting sites based on optimizing the near-term foraging potential of the neighborhood.
Project Objectives and Outcomes:
This project applies the existing model that maps phenotypes preferred by the yellow-billed cuckoo to
over a decade of satellite data to identify the areas that are cuckoo “hot spots’, i.e. which consistently
display greenness dynamics preferred by the cuckoo.
The project objectives are to:
1. Apply the model of Wallace et al. 2013 to map the annual phenological preferences of the
yellow-billed cuckoo within mapped cottonwood-willow riparian vegetation in the study
region.
2. Characterize the differences in cottonwood-willow habitat composition that explain the
distinctive dynamics of landscapes that display preferred phenologies always, never and
sometimes.
3. Disseminate research results via a map of cuckoo habitat “hot spots” and public presentations
to regional managers and interested parties.
Methodology:
The methodology for this project is very straight forward, since the phenotype model has been
already developed. This is primarily an application of the model using existing data and validated
with existing (2012 and 2013) and newly collected (2014) yellow-billed cuckoo survey data. The
steps we propose are as follows:
1. We will apply our model to map yellow-billed cuckoo phenology preferences (Wallace et al
2013) using MODIS-NDVI data for 2001 to 2013. Similar to the AVHRR data used in the
original study, MODIS data are collected daily and composited to form cloud-free images.
The MODIS data, however, are from a newer, better calibrated sensor with a finer (250m)
spatial resolution. The MODIS data are already downloaded, compiled and available from
another project.
2. Cuckoo-preferred phenotypes will be identified within cottonwood-willow and mesquite
vegetation polygons mapped in the 2008 Santa Cruz River vegetation map
(http://www.co.santa-cruz.az.us/com_development/pdf/FinalVegMapReportNovember2008.pdf) and the USGS binational Santa Cruz watershed vegetation map (Wallace
et al., 2011).
3. The models will be validated within the Santa Cruz watershed using bird survey data
collected in 2012, 2013, and new data collected in 2014. These surveys of the Santa Cruz
River riparian corridor are being conducted to model relationships between habitat use and
riparian and landscape history related to disturbance and land use (Villarreal et al. 2012;
Villarreal et al. in prep). The first surveys were conducted during July-August 2012 and
repeated during the same months in 2013. We have 11, 2-km long riparian sites (Figure 2)
from the U.S/Mexico border to the Santa Cruz/Pima County border where we collect two
types of data 1) presence/absence data for the yellow-billed cuckoo, and 2) point counts to
measure general bird diversity. Yellow-billed cuckoo surveys are conducted every 100 m
(along each 2km transect) using call-playback techniques following the protocols developed
by Mathew Johnson, and general bird surveys are conducted every 300 m along the same
transect using visual and aural detection.
4. The modeling results of the 12 years of MODIS data will be overlain with vegetation data to
identify cuckoo habitat areas that display preferred phenology always, never and sometimes.
5. Based on the modeling overlay results, we will select a suite of field sites that represent the
suite of phenotype persistence (always, never, sometimes) and conduct local vegetation
analysis to understand the differences in landscape composition and structure that may
explain the differences in greenness dynamics across these sites.
The project meets several of the SJV Bird Conservation Plan objectives, including Goal 2: Continue
to gather species data and establish a coordinated program to survey, inventory, and monitor the
status and distribution of bird species in the SJV area (We will collect additional data on yellowbilled cuckoo distribution along the Santa Cruz River), Goal 3: Gather and assess habitat data
necessary to quantify objectives and provide recommendations (We will explore the persistence of
cuckoo-favored landscape dynamics across the years). Goal 4: Encourage applied research to provide
guidance in the development of management projects and conservation plans (We will produce a binational map that locates “hot spots” of cuckoo-favored landscape dynamics that can guide future
surveys and identify critical nesting areas for enhanced protection. We will also identify the landscape
components that produce the favorable phenologies; such information can potentially guide
restoration efforts).
Timetable: We will begin the project as soon as funds are released (early June 2014). Modeling will
be accomplished in June and July. Field surveys will begin in July and finish in August. We will
create a map that shows “hot spots” within cuckoo habitat vegetation types that are more likely to
host nesting birds. The map of phenology preferences will be created for the entire study area and,
although most of the field data will be collected in the US along the Santa Cruz River, the resulting
map can provide ecologists in Mexico with promising areas to target for cuckoo surveys. Results will
be presented at the Phenology Research and Observations of Southwest Ecosystems (PROSE)
meeting in October 2014, Tucson AZ.
Map of Project Location: The study area for modeling is the region of southeastern Arizona and
northern Sonora, Mexico shown in Figure 1. The field study site is the Santa Cruz watershed, also
shown in Figure 1.
Evaluation:
The observation that cuckoo prefer particular phenotypes within their preferred vegetation habitat
type demonstrates that habitat suitability and selection is not only determined by the physical
components of habitat, such as topography, species mix, structure and density, but is also determined
by the dynamics of the landscape, which includes the vegetation response to climate. The research
proposed here will determine the persistence of the phenotypes across more than a decade and
examine the landscape to understand the characteristics that produce the range of phenotypes
identified. This information can be used to refine habitat models, inform habitat response to climate
change, and suggest adaptation strategies. We will consider the project outcomes successful if we
successfully locate cuckoo this summer based on the modeling results, if we can discern differences
in the field and in existing detailed vegetation mapping between areas that display preferred
phenology always and never, and if we present the results in at least one venue.
List of partners and their contributions, letters of support: We have worked with Tumacacori
National Historical Park for several years on both vegetation mapping and analysis and yellow-billed
cuckoo surveys. We have a long history of successful research and collaboration with the National
Park Service Sonoran Desert Network Inventory and Monitoring Program where we have worked on
numerous vegetation monitoring and modelling projects on parks throughout the Sonoran Desert
Region. Through our ongoing research on the Santa Cruz River, we have developed close working
relationships with the Sonoran Institute, Friends of the Santa Cruz River, Santa Cruz County
Department of Planning and several private land owners who are interested in preserving and
enhancing the riparian habitat of the river. In addition, there are several people and groups who are
working in the region and have expressed interest in the phenotype model. The yellow-billed cuckoo
is a candidate for listing under the endangered species act. Research to understand habitat
requirements for the cuckoo is crucial for all public land managers, especially if the bird is ultimately
listed.
References:
Villarreal, M.L., Drake, S., Marsh, S.E., and McCoy, A.L. 2012. The influence of wastewater
subsidy, flood disturbance and neighbouring land use on current and historical patterns of riparian
vegetation in a semi-arid watershed. River Research and Applications 28: 1230-1245.
Villarreal, M.L., Norman, L.M., Johnson, M.J. and Kellermann, J.L. In Prep. Integrating natural
disturbance benefits into ecosystem services evaluation of riparian biodiversity. To be submitted to
Ecosystem Services.
Wallace, C.S.A., Villarreal, M.L. & van Riper, C., III. (2013) Influence of monsoon-related riparian
phenology on yellow-billed cuckoo habitat selection in Arizona. Journal of Biogeography, 40, 20942107
Wallace, C.S.A., Villarreal, M.L., and Norman, L.M., 2011, Development of a high-resolution
binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed,
southern Arizona and northern Sonora, Mexico: U.S. Geological Survey Open-File Report 20111143, 22 p. [http://pubs.usgs.gov/of/2011/1143/].
III. Budget
Budget Category
Wallace salary
Villarreal salary
Field surveys/travel
Discounted USGS
overhead (30%)
TOTAL
SJV
Applicant
request Contribution
2600
2600
2490
2307
9997
2600
2600
500
5700
IV. Compliance
Most of our work is GIS and remote
sensing-based and the field work we are
proposing is limited and with passive
measurements. We currently have a
permit with Tumacacori National
Monument to conduct survey data on
the park, and we will request an
extension if this project is funded
(current end date is 6/12/2014):
Study #: TUMA-00029, Permit
#:TUMA-2013-SCI-0003
Name of Principal Investigator: Miguel
Villarreal
Study Title: Patch habitat and landscape
preference of the yellow-billed cuckoo
on the Santa Cruz River
Field survey crews will have State of
Arizona Scientific Collecting permits
through the USGS Sonoran Desert
Research Station.
Figure 1: Location of study area shown on top of a MODIS NDVI
image. The study is centered on the Santa Cruz Watershed and
straddles the US-Mexico border.
Figure 2: Location of the
upper Santa Cruz River
Valley and map location of
study transects for 20122013 yellow-billed cuckoo
surveys. Detailed current
and historical vegetation
data have been compiled
and analyzed at these
locations (Villarreal et al.
2012).
Figure 3: Model for 1998 to predict
distributions of the yellow-billed
cuckoo (Coccyzus americanus
occidentalis) in Arizona, USA.
Landscapes with highly preferred
phenometrics are shown in (a) as
dark green, which are within 0.67
standard deviations from the mean
values modeled as favorable for
cuckoo in all three phenometrics.
Graphically, these dark green areas
are the intersection of the white
areas mapped in (b), (c), and (d),
which show the individual 1998
phenometrics stratified by predicted
cumulative percentage of birds. The
model identifies the most preferred
landscapes as those that experience
peak greenness 29 days later, are 22
magnitude units more dynamic
(36% higher) and 19 units more
productive (0.06% higher) than the
average cottonwood–willow areas
in 1998.