Point-count bird censusing: long-term monitoring of bird abundance and diversity in
central Arizona-Phoenix, ongoing since 2000
Publication date: 2017-11-21
Author(s):
- Heather Bateman, Arizona State University, Polytechnic campus
- Dan Childers, Arizona State University
- Madhusudan Katti, Department of Forestry and Environmental Resources
- Eyal Shochat, Ben-Gurion University of the Negev
- Paige Warren, University of Massachusetts-Amherst
Abstract:
project overview
Over the past half-century, the greater Phoenix metropolitan area (GPMA) has been one
of the fastest growing regions in the US, experiencing rapid urban expansion in addition
to urban intensification. This backdrop provides an ideal setting to monitor biodiversity
changes in response to urbanization, and the CAP LTER has been using a standardized
point-count protocol to monitor the bird community in the GPMA and surrounding Sonoran
desert region since 2000.
The bird survey locations in this CAP LTER core monitoring program include six
general site groupings:
-
ESCA. Forty bird survey locations were selected from a subset of the CAP LTER's
Ecological Survey of Central Arizona (ESCA; formerly named Survey200) long-term
monitoring sites. ESCA sites were located using a tessellation-stratified
dual-density sampling design, and, as such, span a diversity of habitats including
urban, suburban, rural, commercial areas, parks, agricultural fields, and native
Sonoran desert. Earlier versions of this data package included data from the ESCA
project that was intended to complement the bird data. However, while positioned in
close proximity, the bird survey locations do not necessarily overlap with the 30m x
30m plot that constitutes an ESCA sampling location, and leveraging data from these
two monitoring programs should be addressed carefully. ESCA data have corresponding
survey location names, and those data are available through the CAP LTER and LTER
network data portals. At the conclusion of the 2016 spring survey, fifteen of the
ESCA-correlated sites were discontinued as the core monitoring program refocused its
efforts on desert parks and PASS neighborhoods. Among the deleted locations were all
agricultural and commercial sites, as well as sites where access had become
restrictive.
-
North Desert Village (NDV). Additional bird survey locations were positioned in
treatment areas of the North Desert Village (NDV). This was a site of intense study
on the Arizona State University Polytechnic Campus in which the CAP LTER converted
the landscaping of small neighborhoods to reflect the dominant landscaping
preferences employed throughout the GPMA. NDV landscape types include: oasis
(NDV-O), xeric (NDV-X), mesic (NDV-M), control (NDV-C), and native (NDV-N).
Monitoring at NDV was discontinued after the spring 2016 season as research efforts
at this site came to an end.
-
Riparian. While the forty bird survey locations that were selected to coincide
with ESCA sampling locations span a wide diversity of habitats throughout the GPMA,
because of the generally random nature of selecting those sites, they did not
reflect riparian habitats. Riparian areas are important bird habitat but constitute
a very small area of the GPMA. To address this deficiency, bird survey locations
were established specifically in twelve riparian habitats. Riparian habitat
sub-types include: (1) ephemeral-engineered (EE, n=4), (2) ephemeral-natural (EN,
n=2), (3) perennial-engineered (PE, n=3), and (4) perennial-natural (PN, n=3). This
research was successfully concluded and these sites were discontinued after the
spring 2016 season.
-
Salt River. Seven study sites along the Salt River as it runs through the GPMA
that were selected as part of a related study (Salt River Biodiversity Project
(SRBP)) were ultimately included in the CAP LTER's core bird monitoring programs.
These sites reflect continued monitoring of riparian habitat.
-
Desert Fertilization. Beginning with the 2016-2017 winter survey, six sites at
desert parks were added to core monitoring to coincide with the CAP LTER Desert
Fertilization (DesFert) experiment sites.
-
PASS. Beginning with the 2016-2017 winter survey, what used to be a separate
bird-monitoring effort (monitoring in Phoenix Area Social Survey (PASS)
neighborhoods) was incorporated into this core bird-monitoring program. Eight points
were carried over from prior PASS monitoring, and 28 new points established,
resulting in three bird monitoring locations in each of the twelve PASS
neighborhoods. Visiting these locations each year, versus only in years surrounding
the PASS survey as done previously, provides more data on bird populations found in
the neighborhoods of the CAP LTER study area.
method overview
In a given season, each bird survey location is visited independently by three
birders who count all birds seen or heard within a 15-minute window. The frequency of
surveys has varied through the life of the project. The first year of the project (2000)
was generally a pilot year in which each site was visited approximately twice by a varying
number of birders. The monitoring became more formalized beginning in 2001, and each site
was visited in each of four seasons by three birders. The frequency of visits was reduced
to three seasons in 2005, and to two season (spring, winter) beginning in 2006.
Keywords:
urban,
birds,
species abundance,
species composition,
communities,
community composition disturbance patterns,
population studies,
adapting to city life aves,
avifauna cap lter,
cap,
caplter,
central arizona phoenix long term ecological research,
arizona,
az,
arid land
Temporal Coverage:
2000-06-06 to 2017-10-26
Geographic Coverage:
Geographic Description: CAP LTER study area
Bounding Coordinates:
Longitude:-112.742 to -111.622
Latitude:33.8814 to 33.2187
Contact:
Data Manager, Julie Ann Wrigley Global Institute of Sustainability, Arizona State
University,
PO Box 875402,Tempe
caplter.data@asu.edu
Methods used in producing this dataset:
Show
CAP LTER BIRDING POINT COUNT PROTOCOL Revised December 2014
POINT COUNTS
A point count consists of one person standing in a specific location for a fixed
length of time at a specific time of day, and counting all birds seen and/or heard
within a specific distance ("Fixed Radius") or as far as the eye can see ("Open
Radius.")
-
CAP LTER uses 15-minute observation periods
-
Counts are completed within 4 hours of local sunrise (see provided table
for sunrise time)
-
Counts are done using the "Open Radius" method
ADDITIONAL OBSERVERS
The primary observer may be accompanied to the point by an additional observer.
However,only the observations of the primary observer should be recorded on the data
sheet. To avoid any bias that would invalidate the data collected, the secondary
observer should not verbalize, point out birds, or give any non-verbal cues to the
primary observer (e.g., looking at a bird with binoculars is a non-verbal cue). The
second observer should position itself in order to minimize disturbance to birds as
well as to the primary observer. Ideally, the second observer will stand near the
primary observer and slowly move around or bend down so that he/she does not obstruct
the primary observer views.
-
Please note in the "Site Condition" section of the datasheet if an
additional observer was present during the count.
-
If the secondary observer sees a species that the primary observer did not
see, it may be noted in the "Notable additional bird species" section.
COUNT CONDITIONS
-
The first point count should be started no earlier than local sunrise. The
final point count should be finished no later than 4 hours past local sunrise.
-
Do not conduct point counts in steady or heavy rain, though it is
acceptable to conduct counts in light, intermittent drizzle (be sure to make
note of this in the "Precipitation" section of the data sheet).
-
Do not conduct point counts in steady winds above 20 mph (visual cue =
branches of a moderate size move, small trees in leaves begin to sway). Make a
note of the wind condition in the "Wind" section of the datasheet.
-
In the "Disturbance" section, note if yes or no any type of disturbance
occurred during the count, and describe the disturbance under the "Site
Condition" section of the datasheet. A disturbance may involve disturbing you,
the observer (e.g., a homeowner came and talked to you), or disturbing the birds
(e.g., a cat chasing birds, garbage truck making lots of noise and flushing
birds, predator flew by and flushed birds, etc.).
-
If YOU, the observer, are being disturbed during the 15-minute count period
for any reason, make a note of the interruption in the "Site Condition" section.
Time should be paused for the duration of the interruption and resumed once the
interruption event is terminated. Redo the count entirely if you are unsure of
the time you were disrupted for.
-
Make a note of the overall noise condition for the whole count period in
the "Noise" section of the datasheet.
APPROACHING THE POINT and FILLING TOP OF DATASHEET
-
Park your vehicle at >40m from the bird point.
-
Approach the plot as quietly as possible to minimize disturbance to the
birds present.
-
In the "Notable additional bird species" section, make note of any bird
species flushed by the approach in case they do not return during the count.
-
Under "Notable additional bird species", note bird species seen/heard
before and/or after the count. Bird species recorded under this section are
species NOT observed during the count but observed while at the site.
-
Stand quietly at plot center for 5 minutes before starting the count. This
is essential to allow any disturbance caused by the approach to settle down.
-
Use this 5-minute settle-down time to fill out the information at the top
of the datasheet, set up the noise meter, and find your distance brackets (5m,
10m, 20m, 40m) with the range finder. Note that the range finder MAY be in
yards. If so, the conversion of yards to meters is: 5m = 5.4yrd; 10m = 10.9yrd;
20m = 21.9yrd; 40m = 43.7yrd.
-
Record in the "Site condition" section any unusual circumstances around the
plot, such as construction activity or flooding, or anything you noticed that
have changed since your last visit. Also note presence of water (or absence of
it) at sites where water is typically present such as at the riparian sites
(site code starting with "EE", "EN", "PE", or "PN").
-
Record "Site Obstruction" as the percent of the horizon view that is
blocked by something within a 20-m radius of the point. Record this every visit,
even if it does not appear to have changed since your last visit. Record in 5%
increments.
CONDUCTING THE COUNT
After the 5-minute settle-down period, set a watch or timer and conduct the count
for 15 minutes. Rotate slowly in place and record all birds seen and/or heard. For
each observation, note the following in the appropriate column of the data sheet.
Species
-
the four-letter (English name) 54th AOU Supplement (2013) alpha codes if
known (see bird list code provided), or write down the complete common name.
-
If the species cannot be positively identified, use the closest taxonomic
affiliation (it is better to record something as "unknown" rather than
guessing). Make sure you look at all the "unidentified" code options listed on
the bird list code provided to pick the most appropriate code.
Number of Individuals and Distance
-
Usually, a single individual bird will be recorded per line.
-
Only record a number greater than one on a single line if birds of the same
species are observed very close together, such as a flock or family group.
-
If a mixed flock is observed, put each species on a separate line and note
in the "Notes" column that they were part of a mixed flock.
-
Record estimated flock sizes (e.g., "10-20" or "15+") only if you cannot
count them all.
-
Write the number of individuals observed in the appropriate distance
columns.
-
If a bird moves during the count, record only the distance at which it was
first observed.
-
Pay close attention to bird movement to avoid counting birds twice.
-
Birds such as hummingbirds should be recorded in the distance column if
they are using the habitat (such as when they are observed foraging) even if
they are not perched per say. However, if you see them just flying quickly by or
chasing each other, then they should be recorded as FT.
Fly-Throughs (FT)
-
If a bird is seen flying through the count area below the tallest structure
or vegetation, and not observed taking off or landing, record it in the "FT"
column only, not in the distance columns.
-
See note above regarding when to record hummingbirds as FT.
-
High flying birds can be noted as a FT only if they are "aerial screeners"
using the habitat, such as a hawk circling 100 feet overhead looking for food.
Make a note if the aerial screener is flying higher than the tallest structure.
-
You may note in the "Site Condition" section any unusual fly-overs of birds
NOT using the habitat, such as a flock of Pelicans flying above the city.
Seen (S) or Heard (H) Columns
-
Record with a check mark whether the bird was identified from sight (S) or
sound (H), or both. Use caution with similar-sounding birds like Juncos and
Chipping Sparrows, or with mimics and imitators, like Mockingbirds and
Starlings.
Direction
-
Record the direction the bird was first observed or heard. This may mean
recording a bird heard to the south (S) even though you were facing northwest
(N/W) at the time.
-
Use the cardinal and mid-cardinal points of the compass (N, N/E, E, S/E, S,
S/W, W, N/W) in this column.
ADDITIONAL INSTRUCTIONS
-
After the count is completed and before leaving the site, review your data
sheet to ensure you have filled it correctly: make sure you have a count and
distance for all observations, and that the top part of your datasheet is
complete.
-
Record under "Notable additional bird species" section ONLY birds USING THE
HABITAT. This section is to record bird species seen using the habitat, but not
recorded during the count.
-
Under the "Site Condition" section, you may note species such as Cormorants
or Pelicans flying high above but NOT using the habitat.
-
Record under "Non-bird species present" any non-bird species observed at
the site or fresh signs of non-bird species (i.e., coyote scat) at the site
-
Wear drab clothing and avoid bold patterns that might scare away some
birds, or attract other ones.
-
During the count, do not "pish", "squeak", or use any other methods to
encourage birds to show themselves. This would artificially inflate the bird
densities recorded and invalidate the data collected. If you want to see a bird
you had difficulty identifying, you can "pish" only after the count is
completed.
-
Use the 15-minute count period effectively; do not spend precious time
trying to identify a bird that is far enough so that a spotting scope would be
necessary to identify the species.
-
Do not start or continue a count if personal safety is threatened in any
way. Notify CAP LTER bird research group managers of any threat to safety
encountered at a research plot.
-
If the full 15-minute point count survey cannot be completed entirely for
any reasons (e.g. weather, time limits, safety, etc.), the count must be re-done
entirely and completed at another time within the season survey window.
DATA AND COMMUNICATION
-
To minimize errors, please review and complete your data sheets within a
day or so after the survey, preferably the day of the survey. In between others,
make sure you did not leave any blank spaces, review all the alpha codes (if
uncertain of an alpha code, verify it with the bird list code provided or write
the FULL common name), complete your notes and make them concise, and preform
necessary research (listen to calls and/or look at different field guides) to
fill in your uncertain identification(s) when possible. The datasheets must be
clear and easy to read to facilitate data entry and prevent errors.
-
All completed datasheets (reviewed for errors) must be returned to ASU
within two weeks of the last survey completed during that season.
-
To facilitate communication and to aid the supervisor in tracking project
progress and scheduling, make at least one entry per week on the google+ project
resource page – be sure particularly to note if you surveyed all your assigned
sites for the week or if you missed some (specify which ones), report
interesting/unusual sightings and specify where you saw them, and report any
problems (i.e., site access issues, road closures, safety concerns, scheduling
issues, etc).
Data Files (2) :
Tabular:
46_core_birds_ee23527b9fad8b2ead1a6f0b4471ab1e.csv
Description: bird survey sampling details (site, date, time, observer, site conditions, and notes) and birds surveyed (type, number, distance from observer, behavior)
Column |
Description |
Type |
Units |
site_code |
survey location identifier
|
string |
|
location_type |
survey site type
|
string |
Enumeration:
-
ESCA: colocated with Ecological Survey of Central Arizona (ESCA)
-
NDV: North Desert Village, ASU Polytechnic Campus
-
Riparian: Riparian habitat
-
PASS: Phoenix Area Social Survey (PASS) study neighborhoods
-
DesertFertilization: Phoenix area mountain parks that are part of the Desert Fertilization study
-
SRBP: Salt River Biological Project
|
survey_date |
survey date
|
date |
Format: YYYY-MM-DD |
time_start |
survey start time
|
date |
Format: hh:mm:ss |
time_end |
survey end time
|
date |
Format: hh:mm:ss |
observer_name_part |
truncated name of surveyor
|
string |
|
wind_speed |
wind speed
|
float |
kilometersPerHour |
wind_dir |
wind direction
|
string |
|
air_temp |
air temperature
|
float |
celsius |
cloud_cover |
percent cloud cover
|
float |
dimensionless |
survey_notes |
notes regarding survey
|
string |
|
human_activity_notes |
notes regarding any human activity during the survey
|
string |
|
wind |
qualitative assessment of wind speed during the survey
|
string |
Enumeration:
-
none: no perecptible wind
|
precipitation |
qualitative assessment of precipitation during the survey
|
string |
|
disturbances |
indication of a disturbance to the surveyor at the survey location during the survey
|
string |
Enumeration:
-
0: no perceptible disturbance to observer or in the vicinity during the survey
-
1: disturbance occurred during the survey
|
sight_obstruct |
percent of the view obstructed
|
float |
dimensionless |
noise_level |
qualitative assessment of noise level during the survey
|
string |
Enumeration:
-
none: no noise during survey
-
low: low level noise during the survey
-
high: high level of noise during the survey
|
site_condition |
notes regarding the condition of the survey location
|
string |
|
non_bird_species |
notes regarding non-bird fauna observed during the survey
|
string |
|
code |
four-letter alpha code of observed taxon
|
string |
|
common_name |
common name of observed taxon
|
string |
|
distance |
relative distance or position of observed bird(s) relative to the observer
|
string |
Enumeration:
-
0-5: bird observed within zero to five meters of observer
-
5-10: bird observed five to ten meters from observer
-
10-20: bird observed ten to twenty meters from observer
-
20-40: bird observed twenty to forty meters from observer
-
>40: bird observed forty or more meters from observer
-
FT: bird is seen flying through the count area below the tallest structure or vegetation, and not observed taking off or landing
|
bird_count |
quantity of the observed taxon
|
float |
number |
observation_notes |
notes regarding bird observation
|
string |
|
seen |
indication of whether the bird was seen
|
string |
Enumeration:
-
0: bird not identified by sight
-
1: bird identified by sight
|
heard |
indication of whether the bird was heard
|
string |
Enumeration:
-
0: bird not identified by sound
-
1: bird identified by sound
|
direction |
direction of the bird
|
string |
|
QCcomment |
quality control comments
|
string |
|
File:
46_core_bird_locations_500433d02ee19d938b4b4bc48928c6df.kml
Description: bird survey locations