Species Profile:
Magnolia Warbler

Early morning, mid-April, in Parque Metropolitano, a tropical dry forest reserve in Panama City. Smithsonian Institution field technician Alberto Castillo and I are on a birding hike. Binoculars and field guide in hand we tip-toe through the forest. Above us a canopy flock of tanagers, flycatchers, vireos and warblers creates a busy racket with squeaky songs and chips. One tiny warbler catches my attention. He has a thin pointed bill, grey head, white supercilium (eyebrow stripe) and bright yellow rump. His movements are quick, agile, restless, like those of a redstart.

He carries his tail slightly elevated expanding it broadly to display a bright white tail band. That's the giveaway: a Magnolia Warbler (Dendroica magnolia).

This male is in breeding plumage: bright yellow underparts, black streaking on his breast and belly and a black mask. Breeding females are duller. In fall adults and their offspring resemble spring females but have an almost completely grey head and a grey breastband. According to our resident bander, Lori Nichols, Magnolias display a greater variation in plumage than almost any other warbler making identification of sex and age a challenge.

Magnolias are Neotropical migrants. On their wintering grounds from southern Mexico to Panama they spend time in the canopy of dry forests, along forest edges or in scrubby areas - literally soaking up the sun! "Maggies" breed in coniferous and mixed forests across Canada, south through the Upper Great Lakes, New England and the Appalachians. Our bird was most likely on his way north on a journey that would take him along the Gulf coast by late April and into the Great Lakes area by mid May.

Upon arriving in northern woodlands males fight for a territory, then sing their rich, whistled "weety, weety, weetyo" song to attract a mate. The male and female build a loosely constructed, open cup nest with fine hemlock twigs, coarse grasses and dry weed-stalks. The finishing touch is a soft inner lining of fine black roots resembling horse hair. This nest is placed in the horizontal twigs of a fir or spruce from four to six feet up. The female lays three to five creamy white eggs, decorated with spots and blotches of reddish brown, hazel and chestnut. She incubates these eggs for 11-13 days before the chicks hatch. With great efficiency both parents feed their initially blind babies enabling them to leave the nest in only 8-10 days. The adult pair remains in the damp spruce, fir and willow thickets of the north until late August continuing to feed their young and eat copious amounts of insects to store energy for their journey south.

Magnolia numbers are increasing, most likely due to the maturation of abandoned farmland in the Northeast. This is good news, but sadly many still collide with brightly lit skyscrapers and the deceptive windows of homes and other buildings. We at FLAP would be happy to remove Magnolia Warblers from our collection lists and watch their numbers in the wild grow even more.

Deborah Buehler
Deborah is a Master of Science student at the University of Toronto. She has spent the last few months studying rainforest passerines and shorebirds in Panama.