SPECIES

Blackpoll Warbler Setophaga striata Scientific name definitions

William DeLuca, Rebecca Holberton, Pamela D. Hunt, and Bonita C. Eliason
Version: 1.0 — Published March 4, 2020
Text last updated June 4, 2013

Behavior

Locomotion

Walking, Hopping, Climbing

During the breeding season, moves slowly and deliberately along branches while peering at foliage. During migration, forages more quickly.

Flight

Estimated flight speed during overwater migration 38–43 km/h (Nisbet et al. 1963, Williams et al. 1978). No information on shorter flights. Altitudes of migratory flight range from 400 to 6,000 m (Nisbet et al. 1963, Williams et al. 1977a).

Swimming And Diving

Not known.

Self-Maintenance

Preening, Head-Scratching, Stretching, Bathing, Anting

Scratches head by bringing leg over wing (Nice and Schantz 1959a). In late Jul, when adults are molting, preening and head-scratching increase (BCE).

Sleeping, Roosting, Sunbathing

No information.

Daily Time Budget

Little information. Spends substantial part of day perched or singing from perches at tops of conifers (Morse 1979, WVD). See Food habits: feeding and Sounds, above. See also Breeding: incubation, parental care, below.

Agonistic Behavior

Physical Interactions

Males attack and chase each other on their breeding territories during territorial establishment or maintenance; attack and strike with their beaks mounted specimens of other males in breeding plumage that were placed on their territories (BCE, WVD). The aggressor flies in rapidly to the location of the other male. If intruder is not deterred this often leads to physical contact in the air and chases. Females chase other birds that approach their nests, including males that are not their mates, and both sexes chase other species from the vicinity of nest, such as Winter Wrens (Troglodytes troglodytes), Boreal Chickadees (Parus hudsonicus), Magnolia Warblers (Dendroica magnolia), Yellow-rumped Warblers (D. coronata), and American Redstarts (Setophaga ruticilla; BCE). No repulsion interactions observed between any co-occurring species in New Hampshire (Sabo 1980).

Communicative Interactions

Bill-snapping and loud squeaks and chips associated with aggressive behavior. During territory disputes males may perch within a few meters of one another and sing softly with drooped wings (WVD).

Spacing

Territoriality

Breeding territories in the East range from 0.4 to 0.8 ha in the White Mountains of New Hampshire (Sabo 1980, PDH, WVD), and from 0.2 to 1.85 ha (n = 27) on Kent I., NB (BCE). Territory size decreases with increasing elevation (Morse 1979a, Sabo 1980). On Kent I., NB, territory sizes were more variable in years when there was a greater spread in dates of male arrival (Eliason 1986a). No evidence of polyterritoriality (BCE).

Individual Distance

No information.

Sexual Behavior

Mating System And Sex Ratio

On Kent I., NB, 22.6% of 35 males were polygynous; proportion of polygynous males ranged from 8% to 40% over 4 yr of study (Eliason 1986a). No males were mated to >2 females simultaneously. Polygyny occurred in first broods only. Two females that mated with polygynous males for first broods mated with different monogamous males for second broods. On average, 17% (n = 35) of males were unmated for first broods. No unmated females were observed. On Mt. Jefferson, NH, only two of 50 males were polygynous (WVD).

Polygynous males had larger numbers of conifers on their territories than did monogamous males, but territory quality was not correlated to female reproductive success within mating-status categories (Eliason 1986a). Strong site attachment by females may lead to bigamous matings when few males are available early in the season near the females' former nest sites. Any costs of mating with already mated males may be offset by increased reproductive success associated with early nest initiation and competitive advantages conferred by site dominance.

Pair Bond

Male often follows mate closely during nest-building, egg-laying, and incubation. Copulation never observed in 4 intensive years of study. Female occasionally begs and is fed by male: female crouches with open beak and flutters wings. For pairs mated monogamously, pair bonds are maintained throughout the breeding season. In some cases, females that mated with polygynous males for their first broods switched mates for their second broods. Several cases observed of male mating with same female in consecutive years. In all cases, they occupied at least a portion of the same territory from the previous year (BCE).

Extra-Pair Mating Behavior

Not observed, but both mated and unmated males enter the territories of other males and approach females that are mated to other males (BCE, WVD).

Social and Interspecific Behavior

Degree Of Sociality

Generally solitary or in pairs during breeding season, in flocks during migration, sometimes in mixed-species flocks in winter (Sick 1993).

Play

Not observed.

Nonpredatory Interspecific Interactions

Female chases any bird not her mate that approaches the nest. Individuals often join mixed-species flocks during the nonbreeding season. Wintering birds in Venezuela never encountered outside of mixed-species flocks of other wintering warblers and both migrant and resident tanagers (J. Jones pers. comm.). Although breeding range overlaps extensively with its morphologically similar congener, the Bay-breasted Warbler (Dendroica castanea), the 2 species rarely co-occur during the breeding season, except in Green River watershed in n. New Brunswick and on Mt. Jefferson, NH (Morse Morse 1979a, Morse 1989a, WVD). In Quebec, both species coexist at sites with budworm outbreaks and show similarities in foraging patterns (Morse 1979a). Further study of the two species where they occur together is warranted to determine if competition occurs between the two species. May avoid competition with other warblers by means of elevation or foraging methods (Able and Noon 1976). For example, in areas of overlap with Yellow-rumped Warbler in mountains of ne. U.S., Blackpolls forage high and Yellow-rumps forage low (Morse 1989a).

Predation

Little information. Sharp-shinned Hawk (Accipiter striatus) is known predator of adults (Duncan 1980) and nests (WVD). Cattle Egret (Bubulcus ibis) recorded eating grounded individuals during spring migration (Cunningham 1965). Blue Jays (Cyanocitta cristata) and small rodents are likely predators of eggs or nestlings. Gross (Gross 1994) described a female mobbing a Blue Jay that was carrying a nestling in its bill, but the species of nestling was unknown. Gray Jays (Perisoreus canadensis) are likely nest predators as well. A Gray Jay family was observed being very vocal near a nest while the Blackpoll female chipped incessantly nearby; the following day five, 6 d-old nestling were not in the nest (WVD).

Recommended Citation

DeLuca, W., R. Holberton, P. D. Hunt, and B. C. Eliason (2020). Blackpoll Warbler (Setophaga striata), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.bkpwar.01