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Priority Species Documentation

Detecting Rare, Secretive or Priority Species

The Atlas provides a good opportunity to learn more about the rare, secretive, or high conservation priority bird species in the state. Our Species Survey Strategies will help you look for some of these species. Many of these are habitat- and location-specific, so if your block has a wet meadow in northwestern Wisconsin, or a marsh in southeastern Wisconsin, these documents will provide instructions on what special species you should be searching for, and the optimal time of year and methods to seek them. Also consult with your County Coordinator, or post a question to the Discussion Forum or the Facebook Photo & Discussion page for guidance on what to look for in your area.

Documenting Rare or Priority Species

To maintain high data quality and also to provide useful information for management, there are some species for which we need additional information. This information helps us confirm records of uncommon to rare species, and also provides a way to disclose important information on habitat and specific location. Entering this information is vital to helping the WDNR Natural Heritage Inventory map and track these priority species, and provides critical information for conservation planning and management.

For some of the species below, we need information on exact locations. When reporting location, use the decimal degree format (e.g. 44.50121, −88.06212). Preferably, location coordinates can be obtained in the field using a GPS unit. However, assuming you are able to reliably estimate your location, you can also estimate location remotely using the desktop version of the interactive map (go to "Distance and Coordinates", then "Plot" and click the map), or by using the mapping tool on the Priority Species Information Form.

Rare and priority species fall into three levels or categories, each requiring a different reporting mechanism and slightly different degrees of detail.

Level 1 species: For all breeding season sightings, include (a) exact location, (b) habitat code and (c) habitat description in eBird species-level comments. Birds flagged as rare for your area by eBird may require (d) additional supporting details on the bird to confirm the identification. These species are uncommon, sometimes declining nesters that are of high conservation interest.

Northern Bobwhite
Sharp-tailed Grouse
American Bittern (Comments only necessary if Probable/Confirmed)
Least Bittern
Black-crowned Night-Heron
Northern Goshawk (Always hide in eBird during breeding season; see HIDING SENSITIVE SPECIES)
Red-shouldered Hawk (Comments only necessary if Probable/Confirmed)
Common Nighthawk
Olive-sided Flycatcher
Purple Martin (Comments only necessary at a nest site)
Boreal Chickadee
Ruby-crowned Kinglet
Swainson's Thrush
Golden-winged Warbler
Connecticut Warbler
Hooded Warbler
Lark Sparrow
Henslow's Sparrow
Le Conte's Sparrow
Western Meadowlark
Yellow-headed Blackbird

Level 2 species: If Probable or Confirmed, fill out a Priority Species Information Form. When only Observed or Possible during breeding season, simply provide (a) exact location, (b) habitat code and (c) habitat description in eBird species-level comments. Many of these will also be flagged by eBird and require (d) a description of the bird to confirm identification. Some of these species are rare nesters in Wisconsin, others are tracked by WDNR Natural Heritage Inventory.

American Wigeon
Northern Pintail
Common Goldeneye
Spruce Grouse
Greater Prairie-Chicken
Horned Grebe
Red-necked Grebe
Eared Grebe
Western Grebe
Great Egret
Snowy Egret
Cattle Egret
Whooping Crane (Always hide in eBird during breeding season; see HIDING SENSITIVE SPECIES)
Black-necked Stilt (No documentation necessary at Horicon Marsh)
Piping Plover (Always hide in eBird during breeding season; see HIDING SENSITIVE SPECIES)
Upland Sandpiper
Wilson's Phalarope
Great Black-backed Gull
Caspian Tern
Black Tern
Common Tern
Forster's Tern
Long-eared Owl
Short-eared Owl
Peregrine Falcon (Documentation only necessary at a natural nest site [i.e. not on a building])
Acadian Flycatcher
Loggerhead Shrike
Bell's Vireo
Philadelphia Vireo
Great Tit
Carolina Wren
Worm-eating Warbler
Tennessee Warbler
Kentucky Warbler
Kirtland's Warbler (Always hide in eBird during breeding season; see HIDING SENSITIVE SPECIES)
Cerulean Warbler
Bay-breasted Warbler
Yellow-throated Warbler
Wilson's Warbler
Yellow-breasted Chat
Nelson's Sparrow
European Goldfinch

Level 3 species: Fill out a WSO Rare Bird Documentation Form. If Probable or Confirmed, also fill out a Priority Species Information Form. These species are rare nesters in Wisconsin, tracked by WDNR Natural Heritage Inventory, and also are WSO review species.

Yellow-crowned Night-Heron
Yellow Rail
King Rail

If you’ve found a truly rare breeder not listed on the Block Summary Card and also not listed above: Fill out a Priority Species Information Form, and check the WSO Review List to see if you should also fill out a WSO Rare Bird Documentation Form.

Species flagged by eBird: There are some fairly rare birds for which you do not need to fill out the Priority Species Information Form, but you may have to submit documentation elsewhere. For example, there are a few rare but regular breeders in the state that did not make the cut here (e.g., Northern Mockingbird). This is also true for birds that occur out of range (e.g. a Gray Jay in Portage County). These will be evaluated through eBird. In addition to making sure you are filling out information for the species listed above, it is very important to fill out documentation within eBird for species that eBird flags. Bird sightings lacking sufficient documentation may end up being hidden from the public eBird output (and subsequent Atlas products) and we do not want to unfairly reject a record. The primary mechanism for vetting a whole suite of species (the former WSO “Short Form” species) is now through eBird comments.

If a record is flagged in eBird, please add enough detail in the comments box to support your identification — this should include field marks you observed, and why you believed it was this species and not a similar one. If you have doubts about whether or not to enter detailed comments, please enter them anyway. Many of the best eBirders are already in the habit of regularly entering field notes in the comments box. If a species was unfairly flagged as rare and you believe the eBird checklist needs to be adjusted for your area, please contact the Wisconsin eBird team at

Atlasers and County Coordinators should familiarize themselves with the species that require additional information (a handy list is available on the Quick Reference Guide), and we should all make sure the appropriate information gets reported for these priority species.

All checklists and Priority Species Report Forms should be submitted in a timely fashion to avoid duplication of effort and so we can schedule follow-up visits to rare breeders if warranted.

Hiding Sensitive Species

As noted in the Level 1, 2, & 3 lists above, a few species require that you enter the appropriate information, plot it precisely, and then immediately hide the checklist in eBird. It’s probably easiest to submit an observation for any of these species as a separate checklist and just hide that checklist containing the single observation.

Northern Goshawk
Whooping Crane
Piping Plover
Kirtland’s Warbler

Hiding a list in eBird: as soon as you submit your checklist, click the box called “Hide from eBird Output” on the right side of the page. These species will not appear on public output but will appear in your personal lists, and will appear (with reduced location accuracy) in the final Atlas output. These rare species are particularly sensitive to disturbance at the nest site, and are especially attractive for birders, so if you discover a likely nesting area, do the birds a favor and help us reduce potential pressure on that site by hiding the checklist from public view. You may also hide any other species if you feel revealing the nest location could result in disturbance (e.g. a Loggerhead Shrike nest in a roadside shrub).

If you have located possibly breeding birds of the 4 species listed above, please also report them to the following authorities:

Whooping Cranes to USFWS
Kirtland’s Warblers to Kim Grveles
Piping Plovers to Jill Utrup
Northern Goshawk to Rich Staffen