In the 2012 President's Budget Request, the National Biological Information Infrastructure (NBII) is terminated. As a result, all resources, databases, tools, and applications within this web site will be removed on January 15, 2012. For more information, please refer to the NBII Program Termination page.
The Cerulean Warbler
(Dendroica cerulea)
has been identified as a focal species of management concern due to a range-wide population decline of 3.2% per year on the breeding grounds for the period 1966-2005, the steepest decline for any warbler species in North America, and due to threats to its breeding and wintering habitats. Primary factors driving population declines appear to be loss and fragmentation of breeding habitats such as mature deciduous and riparian forests, prevailing silvicultural practices, loss of key tree species on breeding grounds, and modification of montane subtropical Andean forests on wintering grounds.
Date: September 2006
Sources:
Rich, T.D., C.J. Beardmore, H. Berlanga, P.J. Blancher, M.S.W. Bradstreet, G.S. Butcher, D.W. Demarest, E.H. Dunn, W.C. Hunter, E.E. Inigo-Elias, J.A. Kennedy, A.M. Martell, A.O. Panjabi, D.N. Pashley, K.V. Rosenberg, C.M. Rustay, J.S. Wendt, and T.C. Will. 2004. Partners in Flight North American Landbird Conservation Plan. Cornell Lab of Ornithology, Ithaca, NY.
National Audubon Society. 2002. Audubon WatchList: Cerulean Warbler
(Dendroica cerulea)
. Downloaded from (http: www.audubon.org) on 9/6/2006.
Hamel, P.B. 2000. Cerulean Warbler
(Dendroica cerulea)
. In The Birds of North America, No. 511 (A. Poole and F. Gill, Eds.). The Birds of North America, Inc., Philadelphia, Pennsylvania.
Species Profile from NatureServe
Cerulean Warbler Dendroica cerulea
Description:A small (12-cm) canopy-dwelling bird (wood warbler).
Life History:
Reproduction Comments: Apparently a monogamous, single brooded species. The compact nest is built by the female on the lateral limbs of a tree and placed at a considerable distance (e.g., 2-7 m: Harrison 1984) from the bole of the tree, usually saddled on a large, lateral branch, attached perhaps to a small protruding twig. The nest is rather shallow for a warbler (Bent 1953). Variation in site selection is considerable, particularly with respect to the distance from the bole. All authors agree that nests are not built near the ground. Heights from 5-20 m are reported by Bent (1953), Harrison (1984), and Hands et al. (1989), and the typical height is probably above the middle of this range.
The female lays three to five, usually four, eggs. Incubation is believed to be about 12 days (Harrison 1975), and nest life of the young is nine to ten days (n = 1: Southern 1962). The young are fed by both parents, and subsequent to fledging, they move first to lower-level vegetation where their parents feed them, and then gradually farther afield as they approach independence.
Ecology Comments:
In various areas, the highest breeding density was 82-290 pairs per sq km (Robbins et al. 1992). Little work has been done on wintering ecology. J. Fitzpatrick and S. Robinson (pers. comm.) have observed that birds participate in canopy-foraging flocks of forest insectivores, with only one or two warblers in a particular flock. This implies that the foraging flock is a resource that is actively defended by the individual warbler against conspecifics. Though empirical data to support this hypothesis are lacking, this behavioral tendency could be of critical importance. Single flock membership implies a finite limit to the total population; a limit determined by available space. However, these recent findings are in contrast to the earlier reports of movements of large flocks of warblers (Bent 1953).
United States: AL, AR, CT, DC, DE, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, MI, MN, MO, MS, NC, NE, NH, NJ, NY, OH, OK, PA, RI, SC, SD, TN, TX, VA, VT, WI, WV
Canada: ON, QC
Status:
NatureServe Status:
Global Status: G4,
Global Status Last Reviewed: 03Dec1996,
Global Status Last Changed: 03Dec1996,
Rounded Global Status: G4 - Apparently Secure
Reasons:
Large breeding range in eastern North America, but declining, even with population expansion in some areas; decline apparently is due primarily to habitat loss and fragmentation, with the greatest effect perhaps occurring in the winter range in South America.
Other Statuses:
Committee on the Status of Endangered Wildlife in Canada (COSEWIC): Special Concern (01May2003)
IUCN Red List Category: VU - Vulnerable
