Sedge Wrens may exhibit unusal breeding behavior. Some individuals from the upper midwest are suspected to travel and expand into the southern and northeastern parts of their range in July for a second nesting period. (Herkert et al. 2001)
The reasons this species is rare are not entirely known. New York is not in the core of this species range and it is only a local breeder. However, the loss of wetlands due to draining for development and agriculture has likely had an impact and populations historically known from the lower Hudson Valley and Long Island have been extripated (Herkert el al. 2001). There are 38 documented breeding population occurences in New York (New York Natural Heritage Program 2007). More sites are likely to exist in Jefferson and St. Lawrence counties, although it is unknown how many are occupied each year. The number of confirmed or probable atlas blocks increased from 34 blocks in the first Breeding Bird Atlas (1980-1985) to 48 in the second (2000-2005). Although the differences may be the result of lower coverage in the first atlas (McGowan and Corwin 2008).
Breeding Bird Survey data has documented rangewide population increases from 1966 to 1996 largely due to increasing numbers in the Great Plains from habitat reserve programs (Herkert et al. 2001). However, this does not hold true in New York. There was only a small increase in the number of blocks between the first (1980-1985) and second (2000-2005) Breeding Bird Atlas (McGowan and Corwin 2008). Between 1960 and 1974 the colonies located on Long Island and in the lower Hudson area were extirpated. There are only a few known occurences of breeding individuals in southeastern New York since 1980. (Herkert et al. 2001)
The long term trends are unknown. However, loss of wet meadow habitat to agriculture and development and draining wetlands likely impacted this species historically in New York. Levine (1998) reported that the Sedge Wren has likely been extripated from a substantial part of the state, however, reports of early ornithologists indicate that this species has occured in low numbers and locally for at least the past hundred years (DeKay 1844, Eaton 1914)
Habitat loss including draining wetlands for development and agriculture is a historical and present threat. Habitat loss can occur as wet sedge meadow succeed into shrubby areas. Harvesting of hay can destroy nests and kill adults. Migration collisions with towers and buildings has also been reported. (Herkert et al. 2001)
Preservation of nesting habitat is perhaps the most pressing need. The integrity of wetland ecosystems should be maintained. Flooding, draining, and overgrazing can destroy nesting habitat and should be prevented during the nesting season. Riparian-zone management strategies at state and federal owned areas can be adjusted to preserve or create wet meadows and grasslands adjacent to impoundments and other wetlands (Schneider and Pence 1992). Incompatible agricultural practices, such as mowing and haying during the breeding season should be avoided (Herkert et al. 2001).
More research is needed on movements within the range during the breeding season. Also, research is needed on population status at locations on the periphery of the range including monitoring the status of declining northeastern populations. (Herkert et al. 2001)
Sedge Wrens occur in moist meadows with scattered low bushes, grass and sedge bogs as well as coastal brackish marshes where saltmeadow cordgrass (Spartina patens) is dominant. They may also use the upland margins of ponds. Breeding habitats have dispersed small shrubs and little, if any, standing water. Birds may abandon sites that become too wet or too dry. Sedge Wrens nest in dense, tall grass and sedge clumps or hummocks, 2-12" above ground or water level (Bull 1974). Occasionally, they may nest on the ground, in a small bush, or at the base of a small tree (Herkert et al. 2001).
Sedge wrens occur on the Great Lakes and St. Lawrence plains. They are absent from the Adirondacks and Catskills, and were historically found in the Hudson Valley and on Long Island. Sedge Wrens do not overwinter in New York except irregularly; two records exist from Jones Beach and Westhampton Beach on Long Island.
The breeding range of the Sedge Wren extends from southeastern Saskatchewan, central Manitoba, southern Ontario, and central Maine to eastern Kansas, central Missouri, central Indiana and Virginia. It has also nested in small numbers in recent years in New Brunswick and possibly Nova Scotia. Throughout its range the Sedge Wren is sparsely and locally distributed (Gibbs 1992). In the northeastern U.S., tidewater marshes in New Jersey, Delaware, Maryland, and Virginia currently support the largest, most stable populations (Gibbs and Melvin 1992). Northern populations winter from Maryland and Tennessee south to Mexico and east to Florida (Levine 1998).
The Sedge Wren is small brown wren with a streaked back and head.
The Sedge Wren is a small brown wren with a white-streaked back and top of the head. It has a whitish eyebrow that is not a distinct stripe. The throat and belly are whitish with some light brown on the sides and underneath the tail. The rump, top of the tail, and wings are barred with black. The song is described as a "dry stacatto chattering" (Peterson 1980).
The Sedge Wren is a small wren in wet meadow habitat with a streaked back and crown.
Males are territorial during the breeding season although boundaries often shift over the season (Burns 1982). Site fidelity is low in this species, meaning birds may not return to the same location each year which is likely an adaption to breeding in ephemeral habitats (Gibbs and Martin 1992). Local abundances may fluctuate between years and in a given year seemingly suitable habitat may be unoccupied (Andrle and Carroll 1988). During nesting, both sexes have been documented to pierce the eggs of other Sedge Wrens and other species that nest nearby (Picman and Picman 1980). A portion of males (about 20-25%) are polygynous and may have a second female. Pairs may or may not be monogamous for the breeding season and a female mated to a polygynous was documented to attempt a second brood with a different mate (Burns 1992). Females feed the nestlings and males do only occasionally.
There is not a lot of information on what Sedge Wrens eat. It is known that they mainly forage on the ground in an inconspicuous manner that has been described as "mouse-like" (Howell 1932, Walkinshaw 1935). They eat a variety of insects and spiders (Terres 1980) and take their prey from moist soils and among the bases of grasses and sedges.
Nesting phenology, or timing of life stages, for Sedge Wrens may be related to latitude (Schneider and Pence 1992). In parts of the state, territories may not be established until July (Andrle and Carroll 1988). There is some evidence that breeding individuals from the upper midwest could expand into the southern and northeastern parts of the range by July for a second nesting period (Herkert et al. 2001). Look for breeding sedge wrens during the spring and summer from May through September and perhaps especially in July and August.
The time of year you would expect to find Sedge Wren active and reproducing in New York.
Cistothorus platensis (Latham, 1790)
American Ornithologists' Union (AOU). 1983. Check-list of North American Birds, 6th edition. Allen Press, Inc., Lawrence, Kansas. 877 pp.
Andrle, Robert F. and Janet R. Carroll, editors. 1988. The atlas of breeding birds in New York State. Cornell University Press. 551 pp.
Bent, A.C. 1948. Life histories of North American nuthatches, wrens, thrashers, and their allies. U.S. National Museum Bulletin 195. Washington, DC.
Bull, John. 1974. Birds of New York State. Doubleday, Garden City, New York. 655 pp.
Burns, J.T. 1982. NESTS, TERRITORIES, AND REPRODUCTION OF SEDGE WRENS (CISTOTHORUS PLATENSIS). WILSON BULL. 94(3):338- 349.
DeKay, J.E. 1844. Zoology of New York; or, the New York fauna. Part 2: Birds. D. Appelton, and Wiley and Putnam, New York.
Eaton, E.H. 1914. Birds of New York. Part II. New York: University of the State of New York.
Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1992. Birds in Jeopardy: the Imperiled and Extinct Birds of the United States and Canada, Including Hawaii and Puerto Rico. Stanford University Press, Stanford, California. 259 pp.
Gibbs, J. P., and S. M. Melvin. 1992. Sedge wren, CISTOTHORUS PLATENSIS. Pages 191-209 in K. J. Schneider and D. M. Pence, editors. Migratory nongame birds of management concern in the Northeast. U.S. Fish and Wildlife Service, Newton Corner, Massachusetts. 400 pp.
Harrison, C. 1978. A Field Guide to the Nests, Eggs and Nestlings of North American Birds. Collins, Cleveland, Ohio.
Herkert, J.R., D.E. Kroodsma, and J.P. Gibbs. 2001. Sedge wren (Cistothorus platensis). In the Birds of North America, No. 582 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
Howell, A. H. 1932. Florida bird life. Coward-McCann, New York.
Jalava, J. 1993. Status report on the sedge wren CISTOTHORUS PLATENSIS STELLARIS (Naumann) in Canada. Committee on the Status of Endangered Wildlife in Canada (COSEWIC), Ottawa, ON. 50 pp.
Johnson, D. H., and L. D. Igl. 1995. Contributions of the Conservation Reserve Program to populations of breeding birds in North Dakota. Wilson Bulletin 107:709-718.
Levine, E. 1998. Bull's birds of New York State. Comstock Publishing Associates, Ithaca, NY.
McGowan, K.J. and K. Corwin, eds. 2008. The Second Atlas of Breeding Birds in New York State: 2000-2005. Cornell University Press, Ithaca, NY. 688 pp.
National Geographic Society (NGS). 1999. Field guide to the birds of North America. Third edition. National Geographic Society, Washington, DC. 480 pp.
New York Natural Heritage Program. 2007. Biotics Database. Albany, NY.
New York Natural Heritage Program. 2019. New York Natural Heritage Program Databases. Albany, NY.
New York State Department of Environmental Conservation. 1986. New York State Breeding Bird Atlas Database. Wildlife Resources Center. Delmar, NY.
Peterson, R. T. 1980. A Field Guide to the Birds East of the Rockies. Houghton Mifflin Comoany. 383 pp.
Picman, J., and A.K. Picman. 1980. Destruction of nests by the short-billed marsh wren. Condor 82:176-179.
Root, T. 1988. Atlas of wintering North American birds: An analysis of Christmas Bird Count data. University of Chicago Press. 336 pp.
Schneider, K.J., and D.M. Pence, editors. 1992. Migratory nongame birds of management concern in the Northeast. U.S. Department of the Interior, Fish and Wildlife Service, Newton Corner, MA. 400 pp.
Stiles, F. G. and A. F. Skutch. 1989. A guide to the birds of Costa Rica. Cornell University Press, Ithaca, New York, USA. 511 pp.
Terres, J. K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, New York.
Walkinshaw, L. R. 1935. Studies of the short-billed marsh wren (CISTOTHORUS STELLARIS) in Michigan. Wilson Bulletin 52:361-368.
Information for this guide was last updated on: December 10, 2008
Please cite this page as:
New York Natural Heritage Program. 2019. Online Conservation Guide for Cistothorus platensis. Available from: https://guides.nynhp.org/sedge-wren/. Accessed January 18, 2019.