eBird Taxonomy

Taxonomic hierarchy

Our taxonomy is a merger of three different authorities. The eBird taxonomy follows a cascading hierarchy in the following order:

1) AOU (1998) and supplements through 2007, following the North American Classification Committee (NACC)
2) South American Classification Committee (SACC)
3) Clements (2007)

Thus for species treated by the AOU (1998), we follow their taxonomy and nomenclature. For species not treated by the AOU (1998), but treated by the SACC, we use the SACC treatment. And finally, for species treated by neither the AOU nor the SACC, we follow the treatment in Clements (2007).

There are four families for which we have made exceptions: Puffbirds (Bucconidae), Ovenbirds (Funariidae), Antbirds (Thamnophilidae), and Antthrushes and Antpittas (Formicariidae). For all of these taxa the SACC has recently reassessed the relationships, and have reordered the species accordingly. It was not possible to maintain a sensible order of the species with the NACC as the primary authority, so we elected to follow the SACC ordering in these cases, which amount to some minor departures from NACC order.

AOU updates

The NACC updates their taxonomy annually in August, with the publication of their latest supplement. eBird will always update our taxonomy in August immediately following publication of this supplement, so that the bird lists always reflect the most current knowledge.

The SACC updates the taxonomy continually. SACC changes will appear in our August taxonomic update and our January taxonomic update; please understand that performing these updates is quite complex, so we cannot keep up with the weekly changes to the SACC list. 

Subspecies

We believe that reporting of identifiable subspecies is extremely important, and so we have included a long list of field-identifiable subspecies (or subspecies groups) that can be entered in eBird. Since even professional ornithologists have heated disagreements about what subspecies are valid, it was not practical to include all possible subspecies (besides, some only differ based on measurements). When appropriate, we use subspecies groups (like the Sooty Fox Sparrow group, rather than the 10+ subspecies which comprise it). The common names of the subspecies are usually our own, but we have tried to make them descriptive using either names in common usage, names that clarify the main range of the subspecies, or names that describe the plumage; sometimes, we use the scientific subspecies name itself.

Our criteria for inclusion of subspecies, subspecies groups, and distinctive forms are as follows:

1) Distinctive subspecies or subspecies group regularly reported by birders (e.g., Willet (Western), Yellow-rumped Warbler (Audubon's), Fox Sparrow(Thick-billed)) or one which we believe is recognizable in the field and worth increased attention from birders-for example: Green Heron (Eastern) and Green Heron (Western).

2) Distinctive taxon that is widely considered a candidate for a split, although ID criteria are not necessarily widely known or publicized (e.g., White-winged Scoter (American), Greenish Elaenia, etc.). Note that some of these have complicated taxonomy and some of the groups may not correspond to widely accepted subspecies trinomials (e.g., Red Crossbill, Band-rumped Storm-Petrel).

We did not make an effort to include all subspecies, or to include groups that form clines or are exceptionally complicated. Thus, Song Sparrow and Common Yellowthroat, with numerous subspecies (some of which are recognizable in the field) were not treated. The possibility remains of including these (and other) groups in the future as we learn what birders may wish to report. Please let us know if you notice subspecies that meet these criteria but were not included.

Hybrids

We have made an effort to include as many known hybrids as possible as well. While this is not a list of every single hybrid combination reported, we did try to include those that were frequent enough and distinctive enough that they might be reported by birders. These range from the common combinations like "American Black Duck x Mallard" and "Western x Glaucous-winged Gull" to considerably rarer combinations like "Berylline x Magnificent Hummingbird" to "White-throated Sparrow x Dark-eyed Junco." Note that the hybrid names always follow phylogenetic sequence, with the first species in sequence coming first in the hybrid name. All hybrids are followed by the parenthetical note "(hybrid)"-thus you can review all hybrids by searching for (hybrid) within the "Find a species" text box.

Spuhs

Spuhs? What is a spuh, you ask? For difficult to identify groups (like flycatchers) or distant birds (hawkwatchers regularly cope with this problem), birders will often record their identifications only to the genus level, or to some other level above species. "Spuh" is our affectionate term for birds not identified to the species level. Examples include: Empidonax sp., scoter sp., Accipiter sp., or duck sp. Many birders keep track of these sightings, and they can be tracked in eBird as well.

Note that we have two ways of tracking spuhs. Some are listed with the group name and "sp." But when there are only two members of a species pair are possible, we instead have opted to list these with a slash. For example, we do not use "murre sp." but instead list "Common/Thick-billed Murre." The often-used "dowitcher sp." is instead listed as "Short-billed/Long-billed Dowitcher." Other useful listings include: Greater/Lesser Yellowlegs, Semipalmated/Western Sandpiper, and Parasitic/Pomarine Jaeger.

You can review the available spuhs by searching for "sp." in the "Find a species" box and you can review all slash combos by searching for "/".

A work in progress

This taxonomy is a work in progress. If you notice any species, subspecies, hybrid, or "spuh" that is conspicuously absent, please let us know. Furthermore, should you find any errors in spelling, nomenclature, taxonomy, or sequence, please do let us know as well. Since the merger of the NACC and SACC lists was an imperfect process, there are probably areas where the sequence could be corrected or improved; please do let us know if you find these types of errors as well.

APPENDIX A

Inconsistencies in nomenclature between AOU (1998) and supplements and SACC. The eBird taxonomy usually does not follow the SACC in these cases; in some cases the AOU or SACC are considering name changes to bring the two lists into agreement.

The SACC has adopted major changes in order that have rearranged the Tanagers (Thraupidae), Cardinals and Grosbeaks (Cardinalidae), Falcons (Falconidae), Currasows, Guans, and Chachalacas (Cracidae), Hummingbirds (Trochilidae), but we defer to the NACC order in most cases and the NACC has not yet acted on these changes. We do generally follow the SACC for primarily South American groups, including the order of Puffbird (Bucconidae), Ovenbirds (Funaraiidae) and Antbirds (Thamnophilidae). The SACC recently reordered the Turdus thrushes too, and we defer to them on the ordering of those taxa as well (which results in only a very minor change from the NACC order).

A few names continue to be different between the NACC and SACC. Below we list those differences, with respect to the eBird name. eBird follows the NACC in the below cases:

• Black-browed Albatross (Thalassarche melanophris) - SACC uses the scientific name Thalassarche melanophrys
• Black-hooded Parakeet (Nandayus nenday) - SACC uses common name Nanday Parakeet
• White-winged Parakeet (Brotogeris versicolurus) - SACC uses common name Canary-winged Parakeet
• Smoky-brown Woodpecker (Veniliornis fumigatus) - SACC uses scientific name Picoides fumigatus
• Tacarcuna Tapaculo (Scytalopus panamensis) - SACC uses the common name Pale-throated Tapaculo
• Pale-eyed Pygmy-Tyrant (Lophotriccus pilaris) - SACC uses the scientific name Atalotriccus pilaris
• Green Manakin (Chloropipo holochlora) - SACC uses scientific name Xenopipo holochlora
• Blue-crowned Manakin (Pipra coronata) - SACC uses scientific name Lepidothrix coronata
• White-thighed Swallow (Neochelidon tibialis) -- SACC uses the scientific Name Atticora tibialis.
• Tawny-faced Gnatwren (Microbates cinereiventris) - SACC uses the common name Half-collared Gnatwren
• Bare-eyed Thrush (Turdus nudigenis) -- SACC uses the common Name Spectacled Thrush.
• Tricolored Munia (Lonchura malacca) - SACC uses the common name Black-headed Munia
• Java Sparrow (Padda oryzivora) - SACC uses scientific name Lonchura oryzivora

Inconsistencies in taxonomy between AOU (1998) and supplements and SACC. eBird follows the SACC in the below cases:

• Brown Skua (Stercorarius lonnbergi) is not recognized by the AOU (1998:181), who still consider it conspecific with Stercorarius skua (Great Skua).
• Guianan Puffbird (Notharchus macrorhynchos) and White-necked Puffbird (Notharchus hyperrhynchus) are split-only the latter occurs in North America. The AOU is considering this split, and if it accepts it, the scientific name of White-necked Puffbird will change to Notharchus hyperrhynchus. To prevent confusion and to reflect the differing treatments, eBird uses White-necked Puffbird (Notharchus (macrorhynchos) hyperrhynchus).
• Straight-billed Woodcreeper (Dendroplex picus) -- NACC uses the Scientific Name Xiphorhynchus picus