DOI: 10.5061/dryad.5tb2rbp9b
title: Sixty-years of community-science data suggest earlier fall migration and short-stopping of several species of waterfowl in North America

description: Worldwide, migratory phenology and movement of many bird species are
 shifting in response to anthropogenic climate and habitat changes.
 However, due to variation among species and a shortage of analyses,
 changes in waterfowl migration, particularly in the fall, are not well
 understood. Fall migration phenology and movement patterns dictate
 waterfowl hunting success and satisfaction, with cascading implications on
 economies and support for habitat management and securement. Using 60
 years of band recovery data for waterfowl banded in the Canadian Prairie
 Pothole Region (PPR), we evaluated whether fall migration timing and/or
 distribution changed in Mallard (Anas platyrhynchos), Northern Pintail (A.
 acuta), and Blue-winged Teal (Spatula discors) between 1960 and 2019. We
 found that in the Midcontinent Flyways, Mallards and Blue-winged Teal
 migrated faster in more recent time periods, while Northern Pintail began
 fall migration earlier. In the Pacific Flyway, Mallards began fall
 migration earlier. Both Mallards and Northern Pintails showed evidence of
 short-stopping in the Midcontinent Flyways. Indeed, the Mallard and
 Northern Pintail distribution of band recovery data shifted 180 km and 226
 km north respectively from 1960 to 2019. Conversely, Blue-winged Teal
 recovery distributions were consistent across years. Mallards and Northern
 Pintails also exhibited an increased proportion of band recoveries in the
 Pacific Flyway in recent decades. We provide clear evidence that the
 timing and routes of fall migration have shifted over the past six
 decades, but these phenological and spatial shifts differ among species.
 We suggest that using community-science data collected by hunters
 themselves to explain one of the group’s major concerns (changes in duck
 abundance at traditional hunting grounds), within the environmental lens
 of climate change, may help lead to further engagement and two-way
 dialogue to support effective waterfowl management for these culturally
 and ecologically important species.
description: Data Acquisition We requested banding and encounter records from the
 Bird Banding Office (Bird Banding Biology, CWS, bbo@ec.gc.ca) for six
 waterfowl species banded in Manitoba (MB), Saskatchewan (SK), or Alberta
 (AB) available as of 3 December 2020, when we downloaded the data. Our
 initial six focal species all commonly breed in the Canadian prairies:
 Mallard, Northern Pintail, Blue-winged Teal, American Green-winged Teal
 (<em>A. carolinensis</em>), Gadwall
 (<em>Mareca</em> <em>strepera</em>), and American
 Wigeon (<em>M. americana</em>). Digitization of banding
 records was incomplete prior to 1960, so we restricted analyses to
 1960–2019. To assess spatiotemporal changes in waterfowl fall migration,
 we restricted encounter records to birds that died during the first
 hunting season (September - December) after they were banded with
 coordinate precision for encounter location of at least 10-minutes
 (approx. 18.5 km). While the hunting season may extend beyond December in
 some portions of the United States, we excluded records beyond this point
 in our analysis to avoid geographic bias between areas that still had
 active hunting seasons later in the winter vs. those where hunting no
 longer occurred. By the end of December most if not all individuals of our
 focal species will have reached terminal points. Blue-winged Teals and
 Northern Pintails are some of the first ducks migrating southward in the
 fall, with peak migration for both species occurring in September and
 October (Clark et al. 2020, Rohwer et al. 2020). Mallards migrate later in
 the season, with migration peaks between late October to mid-December,
 with some of the most southern migrants overwintering in Mexico beginning
 to arrive by November (Drilling et al. 2020). We included both direct
 recoveries (i.e., birds harvested by a hunter) and birds that were found
 dead, restricted to Canada and the United States. We did not filter by age
 or sex of the bird or time of banding.  Evaluating Spatiotemporal Change in Waterfowl
 Recovery Distribution To assess
 spatiotemporal changes in the phenology and distribution of fall
 migration, we divided the banding and encounter records into three 20-year
 periods (1960–1979, 1980–1999, and 2000–2019) and eight 2-week intervals
 from September through December. Smaller time-steps (e.g., 10-year
 periods) resulted in insufficient and unequal sample sizes, while larger
 time-steps (e.g., 30-year periods) amalgamated too many years to capture
 changes. Two-week intervals provided the shortest time interval to capture
 a ‘snapshot’ of the distribution of recoveries through time that enabled
 sufficient sample sizes. The first two weeks of September had far fewer
 recovery records; Northern Pintail recovery distributions could not be
 assessed during this interval. We restricted analysis of spatiotemporal
 trends in fall migration to Mallards, Northern Pintails, and Blue-winged
 Teals due to sample size limitations for other species (i.e, Gadwalls,
 American Widgeons, and American Green-winged Teals).  Expanding on the approaches taken by Calenge et al.
 (2010) and Green and Krementz (2008), we conducted KDE using the R package
 ‘adehabitatHR’ (Calenge 2007, with an ad hoc smoothing parameter with the
 default grid value of 60) for each species, time period, and interval. We
 extracted Utilization Distribution (UD) contours to produce spatial
 polygons for each of the 50%, 70%, and 90% probability density contours
 using the function ‘getverticeshr’. We assessed spatial relationships
 between the 50% UD KDE contours for each time interval and period using
 approaches from STAMP (Spatio-Temporal Analysis of Moving Polygons, R
 package ‘stampr’) to generate metrics describing change events on spatial
 relationships (Long et al. 2018). For each time interval, we describe
 stepwise change between the 20-year periods in relation to measures of
 distance and direction between polygons, and changes in polygon shape. We
 quantified three distinct types of distribution change events between
 subsequent periods (e.g., comparing 1960–1979 to 1980–1999, comparing
 1980–1999 to 2000–2019). To do this we quantified areas of stability
 (i.e., areas of complete overlap between the time periods), areas of
 expansion (areas only included in the later time period), and areas of
 contraction (areas only included in the earlier time period). Then, we
 quantified the absolute area (km<sup>2</sup>) and proportional
 area that was stable, contracting, or expanding for each 2-week
 interval. 
description: All analysis were carried out using the open-access Program
 R.
description: This README file was generated on 2023-08-31 by Barbara Frei and Amelia
 Cox GENERAL INFORMATION 1. Title of Dataset: Sixty-years of
 community-science data suggest earlier fall migration and short-stopping
 of several species of waterfowl in North America Abstract: Worldwide,
 migratory phenology and movement of many bird species is shifting in
 response to anthropogenic climate and habitat changes. However, due to
 variation among species and a shortage of analyses, changes in waterfowl
 migration, particularly in the fall, are not well understood. Fall
 migration phenology and movement patterns dictate waterfowl hunting
 success and satisfaction, with cascading implications on economies and
 support for habitat management and securement. Using 60 years of band
 recovery data for waterfowl banded in the Canadian Prairie Pothole Region
 (PPR), we evaluated whether fall migration timing and/or distribution
 changed in Mallard (Anas platyrhynchos), Northern Pintail (A. acuta), and
 Blue-winged Teal (Spatula discors) between 1960 and 2019. We found that in
 the Midcontinent Flyways, Mallards and Blue-winged Teal migrated faster in
 more recent time periods, while Northern Pintail began fall migration
 earlier. In the Pacific Flyway, Mallards began fall migration earlier.
 Both Mallards and Northern Pintails showed evidence of short-stopping in
 the Midcontinent Flyways. Indeed, the Mallard and Northern Pintail
 distribution of band recovery data shifted 180 km and 226 km north
 respectively from 1960 to 2019. Conversely, Blue-winged Teal recovery
 distributions were consistent across years. Mallards and Northern Pintails
 also exhibited an increased proportion of band recoveries in the Pacific
 Flyway in recent decades. We provide clear evidence that the timing and
 routes of fall migration have shifted over the past six decades, but these
 phenological and spatial shifts differ among species. We suggest that
 using community-science data collected by hunters themselves to explain
 one of the group’s major concerns (changes in duck abundance at
 traditional hunting grounds), within the environmental lens of climate
 change, may help lead to further engagement and two-way dialogue to
 support effective waterfowl management for these culturally and
 ecologically important species. 2. Author List Amelia R Cox, Barbara Frei,
 Sarah E. Gutowsky, Frank B. Baldwin, Kristin Bianchini, and Christian Roy
 3. Date of data collection (single date, range, approximate date): 1960 -
 2019 4. Geographic location of data collection: North America 5.
 Information about funding sources that supported the collection of the
 data: Environment and Climate Change Canada SHARING/ACCESS INFORMATION 1.
 Licenses/restrictions placed on the data: CC0 1.0 Universal (CC0 1.0)
 Public Domain 2. Links to publications that cite or use the data: Amelia R
 Cox, Barbara Frei, Sarah E Gutowsky, Frank B Baldwin, Kristin Bianchini,
 Christian Roy. 2023. Sixty-years of community-science data suggest earlier
 fall migration and short-stopping of waterfowl in North America.
 Ornithological Applications. https://doi.org/10.1093/ornithapp/duad041 3.
 Links to other publicly accessible locations of the data: None 4.
 Links/relationships to ancillary data sets: None 5. Was data derived from
 another source? No A. If yes, list source(s): NA 6. Recommended citation
 for this dataset: Amelia R Cox, Barbara Frei, Sarah E Gutowsky, Frank B
 Baldwin, Kristin Bianchini, Christian Roy. 2023. Data from: Sixty-years of
 community-science data suggest earlier fall migration and short-stopping
 of waterfowl in North America, Ornithological Applications, 2023;,
 duad041, https://doi.org/10.1093/ornithapp/duad041 Dryad Digital
 Repository. DOI:10.5061/dryad.5tb2rbp9b 7. Description of data source All
 data used in this analysis is derived from publicly accessible bird
 banding records; all data processing scripts are included in this Dryad
 submission. We acquired this dataset from the Bird Banding Lab Database
 through Lesley Howes (Lesley.Howes@ec.gc.ca). Data documentation can be
 found at https://www.pwrc.usgs.gov/BBL/manual/enc.cfm. For this
 publication, we included all band recoveries that were reported by 3 Dec
 2020 for 6 species banded in provinces (B\_REGION): 45 - Manitoba (MB), 04
 - Alberta (AB), 79 - Saskatchewan (SK). The species (B\_SPECIES\_ID) used
 include: 1320 - Mallard (MALL), 1350 - Gadwall (GADW), 1370 - American
 Wigeon (AMWI), 1390 - Green-winged Teal (GWTE), 1400 - Blue-winged Teal
 (BWTE), 1430 - Northern Pintail (NOPI). To run the KDE, STAMP analysis and
 create the GIFs included in the online version of the paper as described
 in the R script
 PrDucks\_6\_ENCdata\_50percentKDE\_STAMP\_plots.animations.R we have
 included the fully transformed data file
 ENC\_6sp\_PrairieDucks\_filtered.csv that is the input at step 3
 (PrDucks\_3\_KDE\_analysis.R). CODE OVERVIEW 1. File list for code All
 analysis was conducted in R version 4.2.3 (2023-03-15). A)
 PrDucks\_1\_BANDdata\_management\_summary.R: Filters and prepares the band
 data for analysis. B) PrDucks\_2\_ENCdata\_management\_summary.R: Filters
 and prepares the encouter data for analysis. C)
 PrDucks\_3\_KDE\_analysis.R: preforms a kernal density estimator (KDE)
 analysis using the R package 'adehabitatHR’ to identify 50, 70, and
 90% Utilization Distributions to track spatio-temporal distributions of
 waterfowl band recoveries during migration by two-week intervals and
 across decades. D) PrDucks\_4\_ENCdata\_KDE\_plots.animations.R: creates
 GIFs and figures of migration paths based on the KDE analysis. E)
 PrDucks\_5\_ENCdata\_50percentKDE\_STAMPmetrics.R: preforms STAMP
 (Spatio-Temporal Analysis of Moving Polygons) analysis to assess changes
 in kernaldensity polygons through the time periods using the R package
 ‘stampr’. F) PrDucks\_6\_ENCdata\_50percentKDE\_STAMP\_plots.animations.R
 : creates GIFs and figures based on STAMP analysis. 2. Relationship
 between code files, if important: R scripts are sequential, with outputs
 in earlier scripts serving as the input for later scripts. DATA OVERVIEW
 All data used in this analysis is derived from publicly accessible bird
 banding records; all data processing scripts are included in this Dryad
 submission. We acquired this dataset from the Bird Banding Lab Database
 through Lesley Howes (Lesley.Howes@ec.gc.ca). Data documentation can be
 found at https://www.pwrc.usgs.gov/BBL/manual/enc.cfm. 1. File list for
 data A) ENC\_6sp\_PrairieDucks\_filtered.csv 2. Relationship between
 files, if important: None 3. Additional related data collected that was
 not included in the current data package: None 4. Are there multiple
 versions of the dataset? No A. If yes, name of file(s) that was updated:
 NA i. Why was the file updated? NA ii. When was the file updated? NA
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: ENC\_6sp\_PrairieDucks\_filtered.csv 1.
 Number of variables: 88 2. Number of cases/rows: 185,155 3. Variable List:
 As there may be changes, if you can please refer to the authoritative list
 of variable codes and descriptions by the Bird Banding Office
 https://www.pwrc.usgs.gov/BBL/manual/enc.php Note that for many variables
 a full description includes additional tabular information that is
 difficult to include in the ReadMe file and instead there are hyperlinks
 to this information on the pwrc.usgs.gov website * 1.B\_AGE\_CODE
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/age.php * 2.B\_REGION
 2-digit "Region" code of banding (not including flyway)
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/reg.php#region *
 3.B\_BAND\_NUM The federal (metallic) band number * 4.B\_BAND\_SIZE\_CODE
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/sizes.php *
 5.B\_BAND\_STATUS\_CODE
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/bandstatus.php *
 6.B\_BAND\_TYPE\_CODE
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/typecode.php *
 7.B\_BIRD\_STATUS
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/birdstatus.php *
 8.B\_COMMENTS Comments added to the banding record by the BBL *
 9.B\_COORD\_PRECISION Level of precision of coordinates given for banding
 location -- 10' block, 1' block or exact
 https://www.pwrc.usgs.gov/BBL/manual/inexact.php * 10.B\_DIRECTION\_CODE
 (Quarter of the Earth) Only needed with B LAT and B LON
 https://www.pwrc.usgs.gov/BBL/manual/dir.php * 11.B\_EXTRA\_INFO\_CODE
 https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/birdstatus.php#extrainfo * 12.B\_FLYWAY\_CODE https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/reg.php#flyway * 13.B\_HOW\_AGED\_CODE https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/age.php#howage * 14.B\_HOW\_SEXED\_CODE https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/sex.php#howsex * 15.B\_LAT\_10\_MIN\_BLK For banding location: BBL-style 10' block designation (latitude) https://www.pwrc.usgs.gov/BBL/manual/loc.php * 16.B\_LAT\_DECIMAL\_DEGREES For banding location: Decimal degrees (latitude). Note the coordinate precision. * 17.B\_LON\_10\_MIN\_BLK For banding location: BBL-style 10' block designation (longitude) https://www.pwrc.usgs.gov/BBL/manual/loc.php * 18.B\_LON\_DECIMAL\_DEGREES For banding location: Decimal degrees (longitude). Note the coordinate precision. * 20.B\_AUX\_MARKER A coded description of any auxiliary markers https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/auxinfo.php * 21.B\_PERMIT\_NUM Permit number of bander * 22.B\_REMARKS Additional remarks from bander * 23.B\_REWARD\_BAND\_NUM The reward band number (if present) * 24.B\_SEX\_CODE https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/sex.php * 25.B\_SPECIES\_ID "AOU" or "SPECIES" number of bird https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/speclist.php * 26.BANDING\_DATE (may be inexact date) Full banding date (MM/DD/YYYY), may be inexact date (records with month &gt; 12 or day &gt; 31) * 27.BANDING\_DAY (may be inexact day) Day of month banded, may be inexact day (records with day &gt; 31) * 28.BANDING\_MONTH (may be inexact month) Month of year banded, may be inexact month (records with month &gt; 12) * 29.BANDING\_YEAR (may be inexact year) Year bird was banded, may be inexact year (records with year = 0000) * 30.B\_MARKER\_LONG\_DESC Full translated auxilliary marker information * 31.B\_SPECIES\_NAME * Species name as originally banded * 32.E\_REGION 2-digit "Region" code of encounter (not including flyway) https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/reg.php#region * 33.E\_CERTIFICATE\_FLAG Did finder request a certificate? * 34.E\_CERTIFICATE\_LANGUAGE Language of certificate to be issued to finder * 35.E\_COMMENTS Comments added to the encounter record by the BBL * 36.E\_COORD\_PRECISION Level of precision of coordinates given for encounter location -- 10' block, 1' block or exact https://www.pwrc.usgs.gov/BBL/manual/inexact.php * 37.E\_COUNTRY\_CODE Country code for country reported ("FIPS" code) https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/country\_codes.php * 38.E\_COUNTY\_CODE County code for county of town/place reported ("FIPS" code) https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/country\_codes.php?country\_code=US * 39.E\_CREATE\_DATE Full date (MM/DD/YY) encounter record was created in BBL * 40.E\_CREATE\_MONTH Month of year encounter record was created in BBL * 41.E\_CREATE\_YEAR Year encounter record was created in the BBL * 42.E\_DIRECTION\_CODE (Quarter of the Earth) Only needed with B LAT and B LON https://www.pwrc.usgs.gov/BBL/manual/dir.php * 43.E\_DIRECTION1 Direction of encounter location from town * 44.E\_DIRECTION2 Second direction of encounter location from town (when 2 cardinal directions are used) * 45.E\_ENC\_COUNTY\_ORIGINAL County code for county in which bird/band was encountered (as reported by finder) https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/country\_codes.php?country\_code=US * 46.E\_FLYWAY\_CODE https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/reg.php#flyway * 47.E\_HOW\_OBTAINED\_CODE Numeric code for how bird/band was obtained https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/howobt.php * 48.E\_HOW\_OBTAINED\_DESC Further description of how bird/band was obtained * 49.E\_LAT\_10\_MIN\_BLK For encounter location: BBL-style 10' block designation (latitude) * 50.E\_LAT\_DECIMAL\_DEGREES For encounter location: Decimal degrees (latitude). Note the coordinate precision. * 51.E\_LOCATION\_DESCRIPTION Description of location reported by finder * 52.E\_LON\_10\_MIN\_BLK For encounter location: BBL-style 10' block designation (longitude) * 53.E\_LON\_DECIMAL\_DEGREES For encounter location: Decimal degrees (longitude). Note the coordinate precision. * 54.E\_MARKER\_CODE\_COLOR\_ID Numeric code describing color of code on auxiliary marker as reported by finder https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/auxinfo.php * 55.E\_MARKER\_COLOR\_ID Numeric code describing color of auxiliary marker as reported by finder https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/auxinfo.php * 56.E\_MARKER\_DESC Actual code on auxiliary marker as reported by finder * 57.E\_MARKER\_REF\_ID Internal identification number given to auxiliary marker only reports * 58.E\_AUX\_MARKER Description of auxiliary marker as reported by finder * 59.E\_AUX\_MARKER\_CODE Numeric code describing type of auxiliary marker as reported by finder https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/auxinfo.php * 60.E\_MILES1 Mileage from encounter location town * 61.E\_MILES2 Second mileage from encounter location town * 62.E\_PLACE\_NAME Place reported by finder * 63.E\_PRESENT\_CONDITION\_CODE Present condition of the bird as reported by finder https://www.pwrc.usgs.gov/BBL/manual/prescond.php * 64.E\_REMARKS Additional remarks by the finder * 65.E\_SPECIES\_NAME Species as reported by finder * 66.E\_STATE\_CODE "FIPS" state code of encounter https://www.pwrc.usgs.gov/BBL/Bander\_Portal/login/country\_codes.php * 67.E\_WHO\_OBTAINED\_CODE Who obtained the bird/band https://www.pwrc.usgs.gov/BBL/manual/WHO.php * 68.E\_WHY\_REPORTED\_CODE Reporting method https://www.pwrc.usgs.gov/BBL/manual/WHY.php * 69.ENCOUNTER\_DATE (may be inexact date) Full encounter date (MM/DD/YYYY), may be inexact date (records with month &gt; 12 or day &gt; 31) * 70.ENCOUNTER\_DAY (may be inexact day) Day of month encountered, may be inexact day (records with day &gt; 31) * 71.ENCOUNTER\_MONTH (may be inexact month) Month of year encountered, may be inexact month (records with month &gt; 12) * 72.ENCOUNTER\_YEAR (may be inexact year) Year encountered, may be inexact year (records with year = 9999) * 73.E\_MARKER\_LONG\_DESC Full translated auxilliary marker information as reported by the finder * 74.HSS Hunting Season Survived. Approximate age of the bird at the time it was encountered * 75.MIN AGE AT ENC Minimum age at encounter based on original banding. The decimal value translates to years and months (e.g. 12.25 = 12 years 3 months) * 76.ORIGINAL\_BAND Original band number if there was multiple bands applied to the bird * 77.Other Bands Additional or replaced band(s) * 78.BEARING The compass direction from the original banding location to the encounter location. Caution, this is not to be interpreted as a direct movement. * 79.DISTANCE The straight-line distance in miles between the original banding location and the encounter location. Caution, this is not to be interpreted as the only distance traveled by the bird. * 80.SAME\_10\_MIN\_BLOCK Indicates if the encounter was in the same 10-minute block of latitude and longitude (Y) or not (N) of the original banding. Note encounters within the same 10-minute block may have actually moved up to 10 miles. Also, records with a "N" in this field may not have actually moved if the DISTANCE field is less than 15 miles due to possible mis-interpretations of 10-minute blocks. * 81\. SPP Four letter species banding code for this analysis \(MALL \- Mallard\, NOPI \- Northern Pintail\, BWTE \- Blue\-winged Teal\) * 82\. B\_PROV Province that the individual was banded in \(AB \- Alberta\, MB \- Manitoba\, SK \- Saskatchewan\) * 83\. yr20 Which of the three 20\-year time periods this encounter belongs in * 84\. wk2 Which of the two\-week fall migration periods the encounter was included for the KDE * 85\. Pacific\_flyway Was this encounter coded to the Pacific Flyway \(NA means no\) * 86\. Central\_flyway Was this encounter coded to the Pacific Flyway \(NA means no\) * 87\. Mississ\_flyway Was this encounter coded to the Pacific Flyway \(NA means no\) * 88\. Atlantic\_flyway Was this encounter coded to the Pacific Flyway \(NA means no\) 4. Missing data codes: NA 5. Specialized formats or other abbreviations used: None