The genus name Setophaga is from Ancient Greek ses, "moth", and phagos, "eating", and the specific petechia is from Italian petecchia, a small red spot on the skin.

[3][4] The 35 subspecies of S. petechia can be divided into three main groups according to the males' head color in the breeding season.

[7] The golden warbler (petechia group; 17 subspecies[4]) is generally resident in the mangrove swamps of the West Indies.

The Cuban golden warbler (S. p. gundlachi) barely reached the Florida Keys where it was first noted in 1941, and by the mid-20th century a breeding population was resident.

[8] Though individual birds may stray farther north, their distribution is restricted by the absence of mangrove habitat.

[4] The American yellow warbler (aestiva group; 6 subspecies)[4] breeds in the whole of temperate North America as far south as central Mexico in open, often wet, woods or shrub.

[3] American yellow warblers breed in most of North America from the tundra southwards, except for the far Southwest and the Gulf of Mexico coast.

[3] American yellow warblers winter to the south of their breeding range, from southern California to the Amazon region, Bolivia and Peru.

American Yellow Warblers arrive in their breeding range in late spring – generally about April/May – and move to winter quarters again starting as early as July, as soon as the young are fledged.

Most, however, stay a bit longer; by the end of August, the bulk of the northern populations has moved south, though some may linger almost until fall.

[11] The breeding habitat of American yellow warblers is typically riparian or otherwise moist land with ample growth of small trees, in particular willows (Salix).

The other groups, as well as wintering birds, chiefly inhabit mangrove swamps and similar dense woody growth.

In particular American yellow warblers will come to suburban or less densely settled areas, orchards and parks, and may well breed there.

Other invertebrates and some berries and similar small juicy fruits[15] are also eaten, the latter especially by American yellow warblers in their winter quarters.

[16] The predators of yellow and mangrove warblers are those typical of such smallish tree-nesting passerines, such as snakes, foxes, birds of prey, and many others.

[19] Carnivores (in particular members of the Musteloidea) including the striped skunk (Mephitis mephitis), long-tailed weasel (Neogale frenata), common raccoon (Procyon lotor),[3] red fox (Vulpes vulpes), and domestic or feral cats, are similarly opportunistic predators.

The yellow warbler is a regular host of the brown-headed cowbird (Molothrus ater), with about 40% of all nests suffering attempted or successful parasitism.

[17] However, success of fledging in yellow warbler nests is usually decreased by the parasitism of cowbirds due to the pressures of raising a much larger bird.

A wintering American yellow warbler examined near Turbo, Colombia was not infected with blood parasites, unlike other species in the study.

[23] In contrast, only 25% of mangrove warbler nests successfully fledge any offspring, with accidents and predation frequently causing total loss of the clutch.

[3] Being generally common and occurring over a wide range, the yellow warbler is not considered a threatened species by the IUCN.

[24] Some local decline in numbers has been found in areas, mainly due to habitat destruction and pollution.

However, stocks will usually rebound quickly if riparian habitat is allowed to recover, particularly among the prolific American yellow warbler.