Nature Of Migration In The Species
Often inconspicuous, thus presence of migrating populations may be underestimated. Generally considered a year-round resident throughout most of range, but many northern breeding populations migrate south as they appear in locations outside of their breeding range, and populations generally increase in southern parts of breeding range during migration. Eastern and northern subspecies, especially americana and alascensis, appear to be strongly migratory, others migrate latitudinally or altitudinally, and southern subspecies appear to be sedentary or local migrants. Probably longer-distance migrations for individuals in northern parts of breeding range. One record of an immature creeper banded in Port Huron, Michigan, on 4 Octoberober and recaptured 10 d later in Sheboygan County, Wisconsin, 442 km west. Some long-distance movements of individuals from USFWS banding records: from Ontario (October) to N. Carolina (Feb), 877 km; Quebec (September) to New Jersey (October), 695 km; Massachusetts (October) to New Jersey (October) 423 km; Wisconsin (September) to Arkansas (Jan), 1,262 km; Ohio (April) to Virginia (October), 522 km. Other distances indicate local migration (8.5-82 km).
Timing And Routes Of Migration
Little information. In Okanagan Valley of British Columbia, appears late September and early October and present until late March-early April. Present all year in s. and central British Columbia. Movements in British Columbia likely reflect both altitudinal and latitudinal migration. Resident on Queen Charlotte Is.. In n. Arizona, more widely distributed from October to early April; also leaves boreal and high mountain forests after breeding season, and is a fall and spring migrant near Flagstaff. Populations in s. Arizona do not appear to migrate; migrants can be seen in the mountains from October to April, and along the lower Colorado River from mid-October to early April. Resident from se. Arizona and sw. New Mexico south to Nicaragua.
Migration noted on offshore islands of Marchitime Provinces. In Vermont, present all year, but migratory movement detected in October, November, March, and April. In Massachusetts, present throughout the year, but populations do migrate, as species is less common in spring than fall; peak for spring migrants in late April-early May, and populations during fall migration vary from year to year, possibly due to weather. In Connecticut, breeding populations migrate south and populations from farther north overwinter; fall peak in late September-October and spring peak in April. In Michigan, an uncommon winter resident, with peak for fall migrants in September and October, and northward migration April-mid-May. Common winter resident in Illinois, with most migrants arriving late September and departing late April-early May. In Ohio, fall migrants appear mid-September along Lake Erie and central and southern counties in late September-early Ocober, and continue until mid-November; northward movements peak in April. Fall peak in Kentucky late October-early November and spring peak late March-late April; fall peak in Minnesota September and October and spring peak April; fall peak in Iowa late September-late October, and spring peak mid April-early May. Other overwintering dates in se. U.S.: 2 October-14 April in S. Carolina; 3 October-8 May in Alabama; 18 October-23 March in Florida; 2 October-17 April in Georgia.
Abundance patterns in winter are complex, with concentrated populations occurring in scattered locations throughout North America (Root 1988). Dense populations found in gallery forests along river valleys in central U.S. (e.g., Platte River) and bluestem prairie-oak-hickory ecotones of Texas, the Midwest, and Great Lakes region. Low concentrations in swamp forests of Mississippi Valley, mixed forests of the Southeast, and in central Oklahoma. In w. U.S., abundance generally low except in dry pine forests (e.g., foothills of Colorado Rockies) and coastal forests. High concentrations found between Montana and Alberta in the Waterton-Glacier National Peace Park.
Thanks to Hejl, S. J., K. R. Newlon, M. E. Mcfadzen, J. S. Young, and C. K. Ghalambor. 2002. Brown Creeper (Certhia americana),no.269. The Birds of North America Online (A. Poole, Ed.).