American Robins in eastern Canada

This is a post I should have written more than a year ago, because eBird seems to have cleaned things up a bit since June 2023 when I noticed it. First, some background.

American Robin is a polytypic species, with Pyle (1998) delineating five subspecies as occurring in Canada and the US:

    caurinus -- breeds coastally from southeast Alaska to northwest Oregon and winters south to southern California

    propinquus -- year-round in the interior from south-central British Columbia and southern Saskatchewan and south to coastal southwest California east to western Texas

    migratorius -- breeds from Alaska south and east to central British Columbia then to central Quebec and southeast to New Jersey and winters south within that range but also south from New Mexico to Florida

    nigrideus -- breeds from northern Quebec through Newfoundland, wintering south to Mississippi and Florida

    achrusturus -- year-round from southeast Oklahoma south to south Texas and east to Maryland south to northern Florida

What I noticed last year is that while Quebec had gobs and gobs of reports of nigrideus, Newfoundland had nearly ZERO, despite that the subspecies was described from that province AND that Newfoundland was littered with reports of the migratorius group subspecies entry. Now, the eBird map shows occurrences of nigrideus only of migrants in the northeastern US, except for some breeders in eastern Newfoundland (the island), a single report from Labrador, and a single winter report from northern peninsular Florida.

That's all fine and good and does not go against our understanding of occurrence. The problem is that eBird shows quite a few June-July reports of American Robin reported to subspecies from the understood breeding range of nigrideus... but reported as of the migratorius group of subspecies. It's possible that those reports were made correctly, but with the incredible murkiness that eBird does so many things taxonomic, it is difficult to assess those reports, either singly or in toto, except that there are no descriptions of what would be out-of-range birds. Then, there is this one. It seems obvious to me that the observer was conflating the migratorius subspecies group with the species epithet migratorius (and that was probably the same mistake made by other such reports), selecting that subspecies entry solely because it happens to be the same as the species name. This checklist has other problems, particularly that the observer obviously reported a bird list from a period of longer than a single calendar day; this checklist should have been invalidated years ago (checklists are supposed to be from a single calendar day). If the above-linked checklist doesn't work for you, then some reviewer or eBird Central has invalidated the report.

I understand that eBird has made changes to what American Robin subspecies entries it wishes included in various filters, and that eBird no longer wishes either nigrideus nor the migratorius group on eBird filters. eBird Central must have changed all those previous reports of nigrideus behind the scenes, but they left alone those questionable reports from Newfoundland of the migratorius group. Somehow, I'm not surprised.


Pyle, P. 1998. Identification Guide to North American Birds, part I. Slate Creek Press, Bolinas, CA.

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