Scientific name: Chordata: Aves: Passeriformes: Troglodytidae: Cistothorus palustris
Common Name: Marsh Wren
Date: 22 April 2001
Photographer: E. M. Barrows
Collector: not appplicable
Location: Dyke Marsh Wildlife Preserve
Keywords: A bird Dyke Marsh Wildlife Preserve DMWP Marsh Wren
A gut of DMWP during high tide.
These views of the Preserve show nesting habitats of the Marsh Wren; no Wrens are visible in these photographs.
Belle Haven Marina, a view for DMWP.
Cistothorus palustris, Marsh Wren (= Long-billed Marsh Wren)(Wren Family, Troglodytidae)
The Marsh Wren nests in many North American marshes including Dyke Marsh Wildlife Preserve (DMWP), Virginia, where it is highly threatened by several factors.
This bird is a much beloved bird of Friends of Dyke Marsh (www.dykemarsh.org), whose newsletter is named The Marsh Wren .
Adults of this species are about 5 inches long (National Geographic, 1994).
They can be locally abundant in freshwater or brackish marshes.
A male sets up his territory in spring and builds several nests in it before females arrive in his area.
A female that is attracted to a male, or his territory, either selects one of his nests and finishes it, or she constructs a new nest from scratch.
If she finishes a male’s nest; she reinforces it and lines it with soft grasses, feathers, cat-tail fluff, or a combination of these materials; and adds an interior sill to the nest’s entrance.
These birds are usually secretive, but males often perch high on cat-tail plants when they sing or investigate intruders.
Males sing during the day and occasionally at night during their breeding seasons, with a series of loud, rapid, reedy notes and liquid rattles.
This species also emits a sharp tusk, often tusk-tusk, as an alarm call.
Sandy Spencer has not heard night singing by the males.
During the evening of 2 May 2001, she lucidly described her 2-year study of Marsh Wrens of Dyke Marsh Wildlife Preserve to the Friends of Dyke Marsh.
DMWP has 154 hectares of marsh.
About 19 hectares are appropriate breeding habitat for these Wrens, and they used about 6 hectares of this habitat in 1998 and 1999.
In DMWP, these Wrens usually nest in cat-tails near steep gut and river banks.
In 1957, a researcher found 87 singing males in DMWP, which was before a company started destroying parts of the marsh when it mined it sand and gravel.
In 1998, Sandy found 31 males with territories, and 7 breeding pairs.
Four nests produced fledglings.
In 1999, she (with more help from others) recorded 34 males with territories, and 14 breeding pairs.
Eleven nests produced fledglings.
Factors that decrease Marsh Wren offspring number are alien invasive plants (such as the vines Field Bindweed and Porcelainberry which cover nesting sites and cause cat-tails to fall over), Marsh Wrens and Redwing Blackbirds which consume eggs, mice and larger mammals such as Raccoons which consume young Wrens, and storms.
Sandy’s research suggests that the most important factor of offspring-number reduction is loss of nesting habitat.
This causes the birds to use less suitable territories which increases conspecific nest predation.
A main conclusion of her work is:
We need a comprehensive annual survey of reproduction of Marsh Wrens in DMWP to assess the success of this bird in the Preserve.
Bump, S. R. 1986. Yellow-headed Blackbird nest defense: aggressive responses to Marsh Wrens. The Condor 88:328-335.
Lesperance, Michelle. 2000. Cistothorus palustris, Marsh Wren. Internet file. http:// animaldiversity.ummz.umich.edu/accounts/cistothorus/ c._palustris$narrative.html
Kroodsma, D. E. and R. A. Canady. 1985. Differences in repertoire size, singing behavior, and associated neuroanatomy among Marsh Wren populations have a genetic basis. The Auk 102:439-446.
Kroodsma, D. E. and J. Verner. 1987. Use of song repertoires among Marsh Wren populations. The Auk 104:63-72.
Kroodsma, D. E. and J. Verner. 1997. Marsh Wren (Cistothorus palustris). Pp. in A. Poole and F. Gill, ed., The Birds of North America, No 308. The Academy of Natural Sciences and The American Ornithologists' Union, Philadelphia, PA and Washington, D.C.
National Geographic Society. 1994. Field Guide to the Birds of North America. National Geographic Society, Washington, DC. 464 pp.
I thank Sandy Spencer for her help with this summary of her work.
E. M. B.