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Methodology for Louisiana Winter Bird Atlas
Van Remsen, Steve Cardiff, Donna Dittmann, & Richard Gibbons
Louisiana Bird Resource Center
Synopsis
The LWBA program hopes to generate maps of relative abundance of birds in the state during late winter. To do this, we borrow the familiar, standard CBC methodology in terms of party-hours and party-miles to generate indices of relative abundance, and apply these to 7.5 quad grid cells, which are roughly 35% as large as a CBC circle. We think that a minimum of 20 party-hours (total; not necessarily all in same day) is necessary to characterize a quad. These can be distributed in any way within the 6-week survey period (over the 3-year life-span of the project). In fact, the same areas can be resampled multiple times as long as the numbers of birds are calibrated by party-hours and party-miles.
The general idea, at least for the quad compilers, is to treat the quad survey as a small, square CBC circle and sample accordingly to produce the standard, familiar "birds/party-hour" data on relative abundance.
Data-entry and display will all be online, in partnership with the eBird program at Cornell Laboratory of Ornithology.
Directions for checking the current list for any quad, go through the following steps:
ebird > Louisiana Winter Bird Atlas (under "Regional Projects Near You", lower right of screen) > View and Explore Data > All Birds at a Location > Atlas Quadrangles in this State ... Continue > pick quad name from the roster that appears ... Continue. This will generate a seasonal checklist that will also include Summer Bird Atlas data as well. If you want to exclude summer-only species, then do "Change Date" and restrict to "Winter."
Goals
1. Publish an atlas of winter bird distribution
for Louisiana using the same 7.5 quad scale as in the Wiedenfeld
& Swan's Breeding Bird Atlas.
2. Add a level of information not present in Wiedenfeld &
Swan or any other atlas to our knowledge, namely information on
relative abundance based on birds/party hour (or party mile for
roadside species). The atlas will reflect these data with perhaps
5-6 color shades, on a scale such as <1/party-hr, 1/party-hr,
10/ph, 100/ph, and 1000/ph.
3. Have all data displayed online as soon as entered by observers
and subsequently filtered by quad compiler. Allow instantaneous
uploading of new data to web page that displays atlas results.
Methods
1. Overview
This survey method combines the grid approach of an atlas with the effort-calibrated approach of the CBC. Breeding Bird Atlases typical provide only presence/absence data and do not provide information on relative abundance. Therefore, they cannot be used to assess differences in relative abundance within a state nor long-term population trends. CBC methodology, in contrast, permits this by calibration of all field data by party-hours, a technique familiar to all birders. The problem with using CBC circles for atlasing is that they are too few and too irregularly distributed geographically. Furthermore, the CBC period is too early in winter, and may not adequately reflect "true" winter populations. The CBC time period is not only short but also conflicts severely with major holidays. Also, CBC circles are so large (ca. 175 sq. miles) that covering them thoroughly requires substantially more effort relative to the roughly 62 sq. miles of a 7.5 quad. Finally, in contrast to atlasing efforts, dates for individual CBCs are set in advance and are essentially irrevocable once set; they are also restricted to a single 24-hr period. The method proposed here blends the strengths of both atlas and CBC methods and minimizes their weaknesses.
2. Specifics
a. Each quad has a compiler responsible for doing surveys and submitting data. Each compiler is encouraged to recruit qualified help to survey their quad. Data gathered within the quad by observers other than the compiler are submitted directly to eBird but are eventually filtered by the compiler before adding to the official database.
b. A survey consists of a bird count, CBC-style with respect to keeping track of numbers of individual birds, party-hours, party-miles, and rough habitat coverage. For inclusion in the atlas, a quad needs at least 20 party-hours of surveying, hopefully more, over the 3-year lifespan of the project. Those hours can be distributed over any number of days within the official "winter atlas" period. Thus, flexibility in survey dates allows avoidance of bad weather, and also permits a single observer to cover different sections of a quad on different days. An ideal survey might consist of the compiler organizing 2-4 teams to survey sections of the quad on a single day, CBC style. As long as party-hour and party-mile data are recorded, the fundamental unit of the atlas, namely birds/unit effort, remains intact. Repeat surveys of the same spots on different days are also possible, again as long as the data are calibrated by effort. In summary, surveys can be conducted as often as resources permit.
c. The minimum unit for data-entry in terms of time period would be 1 hour. This mimimizes the biases of brief sample periods. Once that threshold is reached, all additional time counts toward the total. As with CBC methods, avoid counting same birds more than once in same day.
See FAQ for additional details (and let Remsen know what esle should be addressed at the FAQ)
3. Date Entry --
The Louisiana Winter Bird Atlas has its own data-entry page at eBird:
Data-entry Louisiana Winter Bird Atlas: LWBA .
You have to register first if not already an eBird registrant.
Step 1: under Louisiana Atlas Program,
hit "Submit Observations"
Step 2: either (a) Select from "My Locations" to get
to a quad for which you've previously entered a list, or (b) "Find
it on a Map".
Step 3: click on the red balloon closest to your quad.
Step 4: click on your quad's name.
or
at Step 2, go to "Find it by Quad, City ... " and check the box at the bottom for list of quads. This may be easier than 2b above, but eBird would prefer you use 2b.
BE SURE TO SPECIFIC AN INDIVIDUAL QUAD FOR YOUR DATA ... OTHERWISE THEY DO NOT GO INTO THE LWBA DATA-BASE.
Then, enter your bird data by following the instructions. Put your locality details in the Comments box for reference. If you have problems. let me or Richard know; this is a novel program for eBird, so we're still working out the problems. If you don't have computer access, just send your survey data to us, and we will enter it for you.
Official "Winter" period
Start: 10 January. This avoids the traditional CBC period and also coincides with the empirical observation that many "half hardy" species seem to disappear after early January. To some degree, the latter is an artifact of CBC period coverage, but not entirely.
End: 20 February. With Purple Martins arriving in mid January, some waterfowl beginning to leave in late January, and some residents nesting in January, there is no such thing as a "stable" winter period for the entire avifauna. Late February leaf-out for many trees in southern Louisiana certainly sets a late limit. An "end" date of 20 Feb. extends the period as long as possible without major departure of most winter residents. This may not apply to waterfowl, but waterfowl are not among the species for which this sort of survey is best suited.
Output
The atlas will consist of maps of the state for each species with each quad coded for relative abundance of that species in perhaps 4-6 shades of the same color. The relative abundance scale can vary among species, as can the unit of analysis (e.g., birds/party-hr on foot, birds/party-hr by car, etc.). [Details not important until we have a better feeling for the data.]
For fun, we will maintain tallies of total number of species, total number of party-hours, and so on, divided by region (Coastal Zone, Southern Interior, Northern Interior; see LA subdivisions for boundaries). See either:
Unofficial Quad Stats EXCEL file
for an dowloadable EXCEL file (updated 4 Mar. 2008),
or for just the web page itself (with nagging format problems, largely repaired by David L'Hoste):
Unofficial Quad Stats Web Page
updated 26 Feb. 2008
Timeline:
2006-07 - field-test methods on selected quads; promote
the program; plan for 2008
For Marty Floyd's preliminary map of 2007 coverage, click HERE
2008 - all-out quad surveys
2009 - all-out quad surveys
2010 - produce print version
Quad compiler responsibilities:
o All submitted data will be filtered eventually through the Quad Compiler (details for data submission and uploading to be worked out with eBird and CLO).
o The Quad Compiler will make sure that at least 20 party-hours are invested in the quad between 10 Jan. and 20 Feb. over the lifespan of the project (not just a single year) and will make sure the data are entered into the eBird portal. The minimum unit for data-entry in terms of time period would be 1 hour. Thus, theoretically, you could accumulate the 20 hours on 20 separate 1-hr time blocks.
o Quad Compilers should try to pick survey dates to correspond to good birding weather to minimize "weather effects" on counts. In fact, therefore, we don't see a reason to keep track of weather data for each data entry.
o Quad Compilers should consider organizing one or more all-out 1-day surveys within a quad, carving it up into territories. In other words, make it like a Christmas Count (but one with the flexibility to avoid bad weather and holidays).
Maps.
SEE: http://appl003.lsu.edu/natsci/labirdweb.nsf/$Content/Find+a+Quad?OpenDocument
Also, try:
Once you've located a quad at the latter, you can download a good map as a tiff file and then print that out (or save as pdf file and print that out -- resolution not as good but file size not huge, unlike tiff files).
For Marty Floyd's preliminary map of 2007 coverage, click HERE
Quad Compilers - so far (2008 in blue):
** = already reached threshold of 20 party/hrs
Abbeville East - Richard
Greig
Abbeville West - Richard Greig
Alexandria - Jay Huner
Barataria - David Muth
Barataria Pass - Curt Sorrells
Baton Rouge East ** - Jane
Patterson
Baton Rouge West ** - Steve Cardiff/Donna Dittmann
Baxter Bayou - Roselie Overby
Bayou Boeuf - Lee Ellis
Beggs - Mac Myers
Belle Chase - Lee Ellis
Belle Passe - Dan Purrington
Benton ** - Jeff & Jean Trahan
Bertrandville - David Muth
Blanchard ** - Larry Raymond
Blankston - Joyce Bennett
Bluff Creek - Michael Seymour
Bossier City - Jim Ingold
Boudreaux Lake (Cameron) - Steve Cardiff/Donna Dittmann
Boyce - Jay Huner
Breaux Bridge - Bill Fontenot
Broussard - Danny
Dobbs
Bryceland ** - Rosemary Seidler
Bunkie - Marty Floyd
Buras - David Muth
Cameron ** - Steve Cardiff/Donna Dittmann
Caminada Pass - Curt Sorrells
Carencro ** - Bill Fontenot
Carville - Van Remsen
Cecilia - Bill Vermillion
Chalmette ** - Glenn Ousset
Chef Menteur - Phillip Wallace
Cheneyville - Marty Floyd
Clear Lake - Nancy Menasco
Cocodrie Lake - Jim
Johnson
Colfax - Jay Huner
Collinston East -
Collinston West -
Colquitt - John Dillon
Columbia - Joyce Bennett
Comite ** -- Brian O'Shea, Laurie Binford
Cow Island (Cameron)
- Steve Cardiff/Donna Dittmann
Creole - Steve Cardiff/Donna Dittmann
Crew Lake ** - Joyce Bennett
Delacroix ** - Glenn Ousset
Delcambre - Van Remsen/Elias Landry
DeRidder - Matt Pontiff
Dixie - Paul Dickson
Downsville North - Stephen Pagans/Joan Brown
Duson - Paul Conover/Dave Patton
East Point - Paul Dickson
Elm Grove - Nancy Menasco
Elm Park - Dorothy
Prowell
Elmer ** - Steve Shively
Empire - Devin & Justin Bosler
Enterprise - Joyce Bennett
Evelyn ** - Hubert Hervey
Farmerville - Devin & Justin Bosler
Fearman Lake - Melanie Driscoll
Fish Lake - Stephen Pagans/Joan Brown
Folsom ** - Janine Robin
Forked Island NW
- Paul Conover
French Settlement - Van Remsen
Frost - Jane Patterson
Gardner ** - Steve Shively
Gheens (Lafourche) - Steve Cardiff/Donna Dittmann
Gibsland **- Rosemary Seidler
Gilliam ** - Linda Adrion/Rosemary Seidler
Gilleyville - Joyce Bennett
Gonzales ** - Jacob Saucier
Grand Bayou (Cameron) - Steve Cardiff/Donna Dittmann
Grand Cane - Ron & Susan Martin
Grand Chenier - Dave Patton
Grand Isle - Curt Sorrells
Gueydan - Paul Conover/Dave
Patton
Haaswood - Jennifer Coulson
Hackberry Beach - Steve Cardiff/Donna Dittmann
Hahnville -- Lee Ellis
Hebert - Joyce Bennett
Hebert Lake - Richard Greig
Hellhole Bayou - Melanie Driscoll
Holly ** - Ron & Susan Martin
Holly Beach - Steve
Cardiff/Donna Dittmann
Holum - Joyce Bennett
Homer ** - John Dillon
Hortman - ** Rosemary Seidler
Hurricane Branch - Jim Johnson
Indian Beach - Dan Purrington
Industrial - Phred
Benham/Justin Bosler
Intracoastal City - Richard Greig
Ivan - Jeff & Jean Trahan
Johnsons Bayou - Steve Cardiff/Donna Dittmann
Kaplan North - Steve Cardiff/Donna Dittmann
Keatchie ** - Ron and Susan Martin
Kilbourne - Roselie
Overby
Koran - Jim Ingold
LaBranche - Melvin
Weber/Ron Stein
Lac Sainte Agnes ** - Jacob Saucier
Lacombe ** - Stefan & Mollie Woltmann
LaCour (Pointe Coupee) - Steve Cardiff/Donna Dittmann
Lake Cataouatche East - David Muth
Lake Charles SE - Steve Cardiff/Donna Dittmann
Lake Providence - Devin & Justin Bosler
Lafayette - Dave Patton
Langston - John Dillon
La Place ** --
Melvin Weber/Ron Stein
Latanier Bayou - Paul Conover
Leeville - Dan Purrington
LeRoy - Erik Johnson
Leton - John Dillon
Little Woods **
- Glenn Ousset
Lockport - Lee Ellis
Luling - Peter Yaukey
Madisonville **
- Chris
Brantley
Mandeville - Chris Brantley
Mangham - Joyce Bennett
Maringouin NW - Brian O'Shea
Mason - Joyce Bennett
Milton -- Erik Johnson
Minden North - Minden High Nature Club
Mooringsport - Larry Raymond
Monroe North - Janis Harrison
Mt. Airy NW - Richard Gibbons
New Orleans East
- Phillip Wallace
New Orleans West - Peter Yaukey
New Roads - Mara Domingue
Nicholson - Jennifer
Coulson
North Highlands - Larry Raymond
Oak Grove -- Roselie Overby
Pass Tante Phine - Dan Purrington
Patterson - Jay Huner
Peveto Beach - Steve
Cardiff/Donna Dittmann
Phoenix ** - Glenn Ousset
Pioneer - Roselie Overby
Pilottown - Dan Purrington
Plaquemine - Van
Remsen, Steve Cardiff/Donna Dittmann
Plaucheville ** - Jacob Saucier
Point - Stephen Pagans/Joan Brown
Point a la Hache - Phillip Wallace
Pontchatoula - David Brown
Port Arthur SE (for Sabine Pass, LA) - Steve Cardiff/Donna Dittmann
Port Sulphur - Curt Sorrells
Portage - Bill Vermillion
Powhatan - Paul Dickson
Rapides ** - Steve
Shively
Rayville ** - Joyce Bennett
Rigolets - Phred Benham/Justin Bosler
Rocky Branch - Stephen Pagans/Joan Brown
Rosepine - Matt Pontiff
St. Francisville - Keith Ouchley
St. Gabriel ** - Van Remsen, Donna Dittmann, Steve Cardiff
St. Landry -
Savoie - Lee Ellis
Shreveport East ** - Jean and Jeff Trahan
Shreveport West - Charlie Lyon
Simsboro - Rosemary
Seidler
Smith Bayou - Steve Cardiff/Donna Dittmann
Sorrento - Jay Huner
South Point - David Muth
Spanish Fort - Phillip Wallace
Spring Ridge - Larry Raymond
Stonewall ** - Hubert Hervey
Sulphur - Devin & Justin Bosler
Summerfield - John Dillon
Tallulah - Devin & Justin Bosler
Tensas Bluff - Devin & Justin Bosler
Thornwell - Steve Cardiff/Donna Dittmann
Triumph - Curt Sorrells
Venice - Dan Purrington
Vinton - Devin &
Justin Bosler
Vivian North - Richard Gibbons
Vixen - Joyce Bennett
Wallace Lake - Mac Hardy
Watson ** - Laurie Binford
Weeks - E. Johnson
Welsh North - Devin & Justin Bosler
West of Johnsons Bayou - Steve Cardiff/Donna Dittmann
West Monroe North ** - Stephen Pagans/Joan Brown
Weyanoke ** - Phil Stouffer
White Castle - Van Remsen
Womack - Devin & Justin Bosler
Woodworth East - Marty Floyd
Woodworth West ** - Steve Shively
Wright - Dave Patton
Youngsville - Erik Johnson
=======================================
[Heavily birded quads that need leaders]
Duson
Thibodaux
start 24 Jan. 08
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