Cerulean Warbler (Septophaga cerulea)
Length: 4.70 in
Wing span: 7.50 in
Weight: 9.4 g
Buzzy, ascending song. The 3-part song (Type A1) starts with 2-5 buzzy notes, then 4 or 5 fast warbles, and ends with higher pitched buzzy trill. Also sings a 2-part song (Type A2) that lacks the first section of Type A1. A third song type, Type A3 also occurs; similar to Type A1 but slower. Contact call is a buzzy zeet and alarm call is a sharp chip.
(Recordings from xeno-canto.org. Spectrographs generated in Audacity)
Male: A small, short-tailed, short-legged warbler with a stout bill and pointed wings. A sky blue songbird with a cerulean neck band and streaks on flanks. White throat and bold white wing bars. From above blackish streaks on back. From below white tail spots are visible.
Female: Dusky blue and olive green above with no streaking on back. Lacks neck band, but wing bars present. Also has a broad whitish eyebrow.
Immature: Like a dull female and has a wash of yellow on breast.
In flight: Fast, strong, direct, and slightly jerky; wingbeats deep and still. Front heavy bird with very short tail and pointed wings.
Cerulean warblers are most closely related to Cape May warblers, Northern and Tropical Parulas.
Cerulean warblers breed in mature deciduous forests with tall trees (often oaks) with a dense canopy and lower understory. Found most often along steams, wet areas or high on ridges. They tend to establish territories in the interior top third of trees, especially white oaks, bitternut hickories and sugar maples.
Foods & Foraging
Cerulean warblers are insectivores, consuming primarily flies, beetles and caterpillars. Preference is to feed in gaps high up in the canopy where the birds hop on branches and pick insects from leaves and twigs. They tend to be very methodical while foraging. They are considered hover-gleaners, but sometimes sally to capture their prey.
The Cerulean Warbler breeds from extreme southwestern Quebec and southern Ontario, west to Minnesota and Nebraska, and south from eastern Kansas to South Carolina. Spends winters in montane forests of northern South America.
Birds arrive in our area toward the end of April and those that stay to breed depart again by September.
Click here to see how the range of the Cerulean Warbler could be reshaped due to climate change.
Arrival & Departure
The Cerulean Warbler is an uncommon bird in its range and has seen a population decline of 72% from 1970-2014. The global population stands at about 560,000 and if current trends continue then half the population will be lost by 2041. Habitat loss and degradation of its habitat are major causes of its decline.
Conservation efforts by the American Bird Conservancy and other groups aim to reverse these trends by focusing on forestry practices such as long rotation timber harvest and selective logging to create the birds desired canopy forage sites.
The Cerulean Warbler is on several watch lists and IUCN lists them as vulnerable:
Cerulean Warbler: Vulnerable
Vulnerable category includes birds that are at a high risk of becoming endangered.