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This month's Niagara Escarpment species:

Cerulian Warbler (Dendroica cerulea) -Blue Flash in the Forest Canopy 

Did you Know? The female Cerulean Warbler has an unusual way of leaving the nest after sitting on the eggs. She drops from the side of the nest, keeping her wings folded to her sides, and opens her wings to fly only when she is well below the nest and almost to the forest floor. It is often referred to as "Bungee jumping".   The cerulean warbler is an evasive bird, you will often hear its song but rarely see it because it spends the majority of its time in the upper canopy of the forest, flitting from branch to branch as it forages for food.  Photo Credit: Mdf (Wikipedia)

Habitat:  Breeds in forests with tall deciduous trees and open understory, such as wet bottomlands and dry slopes.  Winters in broad-leaved, evergreen forests of South America.

 Length: 11cm  Weight : 8 - 10 grams

Diet:  insects

Status: Endangered in Canada, Special Concern/ S3B in Ontario

Identification : Breeding adult males have a deep cerulean blue on the back with blue streaking on the sides of the breast and a white throat and underparts as well as two white wingbars. Have a dark band across throat and into the eye. May have faint black streaks on back.  Non-breeding males and adult females are Bluish-green on their backs with no streaking. Whitish-yellow on the underparts with a white or yellowish line over eye. Dusky streaking down sides of breast and two white wingbars. The song of the male Cerulean Warbler is a series of buzzy notes ending in a high pitched trill.

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Cerulian Warblers on the Bruce Trail

Cerulean Warblers breed from southwestern Quebec and southern Ontario West to Minnesota and Nebraska, south to eastern Texas and North Carolina. Two distinct populations in Southern Ontario are known to exist. One runs from southern Lake Huron to north of Lakes St. Clair and Erie, with an area of concentration lying roughly between the Long Point region and western Lake Ontario. The second population runs from the Bruce Peninsula and Georgian Bay area to the Ottawa River. The large tracts of interior forest along the Escarpment provide ideal habitat for this bird.

When the breeding season is over they migrate to their wintering grounds in the forests at the base of the Andes Mountains in South America.

Interesting Facts:

• Nest is an open cup made of bark fibers, grass stems, and hair bound together with spider webs and is built on a limb of a deciduous tree high up in the forest canopy. If the nest fails, females will reuse the webbing from the first nest to rebuild the second one as it is too time consuming to gather more of the valuable spider web.
• Cerulean Warblers are forest-interior birds that require large, undisturbed tracts of mature, semi-open deciduous forest.

Cerulian Warbler - Species at Risk

This little bird is a Species at Risk in both Ontario and Canada, designated as Special Concern provincially and federally Endangered.The main threat to this warbler is habitat loss both in its breeding and wintering grounds where logging and development result in forest fragmentation and degradation. This adds another threat as nest parasitism by the Brown-headed Cowbird becomes an increasing problem as cowbird populations are greater in degraded forest habitats. This warbler has experienced the largest population decline of any North American wood warbler. There are estimated to be between only 500 and 1,000 breeding pairs in Canada, with the majority in Ontario. The Bruce Trail Conservancy is working to protect habitat for Cerulean warblers in Ontario along the Escarpment by securing land to connect natural areas and create large tracts of interior forest for this warbler and other sensitive species.

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