USGS



BIOLOGICAL AND ECOTOXICOLOGICAL CHARACTERISTICS OF TERRESTRIAL VERTEBRATE SPECIES RESIDING IN ESTUARIES

Seaside Sparrow Seaside Sparrow
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Biological Characteristics

Species Ammodramus maritimus consists of seven distinct subspecies (see map for distribution).  Overall body size can range from 13.0 - 14.7 cm in length and weight is approximately 19 - 29 grams.  Plumage is melanistic (degree of melinism varies among sub-species) with olive coloration on wings, back, and flanks. Lores and lesser coverts at wrist are distinctly yellow.  The chin and throat are white, the moustachial stripe is gray, and the malar stripe is buffy.  Bill is apparently larger than other salt marsh sparrow species. Sexual dimorphism is not displayed in this species (Post and Greenlaw, 2009).
Status in Estuaries Seaside sparrows are semi-territorial and nest in close proximity to conspecifics depending on marsh quality.  Sparrows in the northeast construct nests of thatch from Spartina patens and S. alterniflora. Nests are found in marsh grasses S. alterniflora, S. patens, and sometimes at the base of Iva frutescens mixed with grasses (Marshall and Reinert, 1990).  Nests are approximately 5 - 20 cm above ground, making this species susceptible to predation and flood events. Clutch size is approximately 2 - 5 buff and spotted eggs.  Multiple clutches may be attempted throughout the breeding season (Post and Greenlaw, 2009).
Abundance and Range Due to their habitat specificity, seaside sparrows have restricted range inhabiting marshes only along the Atlantic and Gulf coasts, ranging from Maine to the eastern Texas coast.  The northeastern subspecies can be migratory depending on winter temperatures and other factors.  Seaside sparrows are habitat specialists, spending their entire life cycle in tidal marshes (Robins, 1983).  The population estimate is approximately 110,000 individuals (Birdlife International, 2010).  However, the population estimate for the subspecies Cape Sable Seaside Sparrow (A. m. mirabilis) estimated 7000 in 1981 and dropped to 3148 by 2007 (NPS  Survey Report, 2007). 
Site Fidelity Seaside sparrows exhibit strong nest site fidelity (Post, 1974), have a socially monogamous reproductive strategy, and both male and female share parental care.  In areas where breeding populations are abundant, this species is easy to find, and males often sing throughout the day depending on daily temperature.  Seaside sparrows can be harder to detect during the winter season, as sparrows are elusive often seeking refuge in the marsh grasses. 
Ease of Census Simple: Seaside sparrows are highly mobile, semi-colonial, easy to capture, abundant in ideal habitat, long lived for a passerine (approximately 7 years), spend entire life in same type of habitat (salt marsh), and feed on aquatic macro invertebrates and insects.  
Feeding Habits Seaside sparrows forage in shallow muddy areas of the marsh along the banks of ponds, and by gleaning prey off of tidal marsh vegetation.  Much like a shorebird, seaside sparrows use their bill to probe mud below the surface and feed on macro-invertebrates, as well as glean prey items off of salt marsh grasses and shrubs.  Their main prey consists of adult and larval insects, spiders and their egg cases, and amphipods (Post and Greenlaw, 2009).
Conservation Status

Seaside sparrows are threatened by habitat degradation (Greenlaw, 1992), invasion of exotic vegetation species, sediment erosion, sea-level rise, and contaminants.  Seaside sparrows are listed as a bird of conservation concern and high priority in terms of research needs on the Fish and Wildlife (FWS) Partners in Flight Watch List (http://www.partnersinflight.org/WatchListNeeds/).  
The Cape Sable Seaside Sparrow (A. m. mirabilis) is on the FWS endangered species list (http://www.fws.gov/endangered/wildlife.html).

The Dusky Seaside Sparrow (A. m. nigrescens) of eastern marshes in Florida is extinct due to habitat degradation, and the last individual died in captivity in 1987.

Saltmarsh Sparrow Contaminant Exposure Data

I.

Organochlorine Contaminants

1.

No direct exposure data available

II.

Cholinesterase-Inhibiting Pesticides

 

No direct exposure data available

III.

Trace Elements, Metals and Metalloids

1.

. In Connecticut, blood from seaside sparrows was collected at Hammock River and Hg concentrations averaged 0.25 µg/g (ww) (N=3).  At McKinney National Wildlife Refuge - Great Meadows, blood concentrations averaged 0.56 µg/g (ww) (N=3) (Lane and Evers 2006).

2.

Blood samples were collected from seaside sparrows and analyzed for Hg (µg/g ww) at five drainages (2007 - 2008) along the Delaware Bay (Warner et al. 2010). No difference was found in blood Hg concentrations between males and females.  At Prime Hook National Wildlife Refuge sparrows nesting at two drainages (Broadkill and Cedar Creek) were sampled within the refuge.  Mercury concentrations in sparrows at Broadkill River ranged from 0.22 - 0.63 with mean 0.43 (N=14).  Sparrows sampled at Cedar Creek ranged from 0.18-0.56 with the mean 0.31 (N=15).  At Bombay Hook National Wildlife Refuge, Hg concentrations in sparrows at Green Creek ranged from 0.33 - 1.47 with the mean 0.60 (N=18).  Concentrations in sparrows at Duck Creek ranged from 0.18 - 1.99 with the mean 0.45 (N=32).  At Woodland Beach Wildlife Area, sparrows nesting at Smyrna River had Hg concentrations that ranged from 0.15 - 2.12, with a mean 0.57 (N= 21).  

IV.

Petroleum

 

No residue data available

Seaside Sparrow Contaminant Response Data

I.

Organochlorine Contaminants

 

No response data available

II.

Cholinesterase-Inhibiting Pesticides

 

No response data available

III.

Trace Elements, Metals and Metalloids

No response data available

IV.

Petroleum

 

No response data available

References for Seaside Sparrows

Birdlife International. 2010. Assessed June 16th 2010. (http://www.birdlife.org/)

Greenlaw, J.S. 1992. Seaside Sparrow, Ammodramus maritimus. In K.J. Schneider, and D.M. Pence, eds., Migratory nongame birds of management concern in the northeast. U.S. Department of Interior, Fish and Wildlife Service. Newton Corner, MA. USA, pp. 211-232.

Lane, O.P. and D.C. Evers. 2006.  Methylmercury availability in New England
estuaries as indicated by saltmarsh sharp-tailed sparrow, 2004-2005. Report BRI 2006-01. BioDiversity Research Institute, Gorham, ME, USA.

Marshall, R.M. and S.E. Reinert. 1990.  Breeding ecology of seaside sparrows in a Massachusetts salt marsh. Wilson Bull. 102:501-513.

Post, W. 1974.  Functional analysis of space related behavior in the seaside sparrow. Ecology 55:564-575.

Post, W. and J.S. Greenlaw. 2009. Seaside sparrow (Ammodramus maritimus), The birds of North America online. In A. Poole, ed., Ithaca: Cornell Lab of Ornithology; Retrieved from the birds of North America online: http://bna.birds.cornell.edu/bna/species/127doi:10.2173/bna.127

Robbins, C.S. 1983.  Distribution and migration of seaside sparrows. In T.L Quay, J.B. Funderburg, Jr., D.S. Lee, E.F. Potter, and C.S. Robbins, eds.  The Seaside Sparrow, its Biology and Management. Occas. Pap. North Carolina Biol. Surv. Raleigh, NC. USA.  pp. 31-40.

U.S. Fish and Wildlife Service, Partners in Flight Program, National Conservation Status of Spacies Listing (http://www.partnersinflight.org/WatchListNeeds/).

U.S. National Park Service, Department of Interior, Accessed April 29th 2010.  Status of the cape sable seaside sparrow 2007 survey report. (http://www.nps.gov/ever/parknews/status-of-cape-sable-seaside-sparrow-2007-survey-report.htm).

Warner, S.E, W.G. Shriver. M.A. Pepper, and R.J. Taylor. 2010. Mercury concentrations in tidal marsh sparrows and their use as bioindicators for the Delaware Bay, USA. Environ. Monitor. Assess. DOI: 10.1007/s10661-010-1312-z.

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