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education: birds of georgia LeConte's Sparrow, Ammodramus leconteii
Status: Rare and local winter resident and migrant south of Mountains; uncommon in western Coastal Plain, 10 Oct (1979) - 10 May (2000). Extreme dates: Piedmont 24 Oct - 10 May, Coastal Plain 28 Oct - 8 Apr, Coast 10 Oct- 3 Mar. High count: 51 on 21 Nov 1999 at BUENWR (Beaton et al. 2003). The skulking nature of the species and the unwelcoming nature of its winter habitat make it difficult to observe and its status hard to assess. Its numbers in the western Coastal Plain were not known until 21 Nov 1999 when a group of Georgia birders counted 51 in a single area at BUENWR ( Stewart ). Much of its wintering area on the Coast is inaccessible to the public. Research in breeding range in n Great Plains (Ingl and Johnson 1995, 1996) and in wintering range in TX (Grzybowski, J.A. 1980) found more birds in wet years than in dry years. Wintering populations in GA may follow a similar pattern, but more research is needed. Habitat: Breeding: Prefers open habitat and damp to wet, marshy meadows (Peabody 1901) with fine grasses and sedges, and dry borders of rush-filled marshes. In Alberta, found in sedge meadows, around bogs and marshes in thick grass and shrub tangles, and in the low, damp part of hay fields; in mountainous areas, found in flooded grass and sedge meadows (Somenchuk 1992). In Michigan, largest population in sedge meadows at Seney NWR (Brewer et al. 1991). Elsewhere, habitat similar (Letourneau and Aubrey 1996). While moist habitats are often preferred, they are not a requirement for nesting. One study of 24 territories in MN found as follows:16 were at least 65% fallow fields that included several grasses such as smooth brome (Bromus inermis) and Kentucky Bluegrass (Poa pratensis); 7 were at least 90% fallow fields; 2 were 60% wet grass with short stem bulrush, reed canary grass and smooth brome; 5 were within an annually cut hayfield with alfalfa, clover and Kentucky Bluegrass; and 1 was 80% overgrown sunflowers invaded by timothy (Cooper 1984)(Lowther, P. 2005). Winter: In GA, prefers large open damp fields or power-line cuts of broom sedge (Andropogon sp.) but also found in damp fields of other grass species such as Panicum sp. And other rank grasses. Prefers knee-high grass but sometimes found in waist-high grass (P.Howard pers.comm.). Reaches high densities on TX coast in winter. Never found in large numbers in GA until the discovery of a population at Eufaula WMA (Stewart ) on 21 Nov 1999 when 51 were found in one extensive open, flat low-lying field with a cover of dense grass including Andropogon. This discovery shed new light on the possibilities for finding wintering LeConte's in the western Coastal Plain since most effort had previously been directed to the eastern Coastal Plain near the Coast. Diet: Seeds and arthropods. Analysis of gizzard content of 15 individuals in MO indicates the consumption of the following seeds in an amount > 1%: big bluestem, 1.5%; Andropogon scoparius, 6.6%; Andropogon sp., 22.1%; Myosotis verna, 13.2%; Panicum lanuginosum, 2.9%; Setaria glauca, 16.9% ; Sorghastrum nutans, 14.7% ; Sporobolus heterolepis, 7.2%. Also the following arthropod groups: Arachnida, 3.7%; Curculionidae, 3.7%; Cicadellidae, 7.4% (Lowther, P. 2005). Migration: Short distance migrant moving seasonally between breeding areas and wintering grounds in North America. Breeds in e ND, ne SD, n MN, n WI, n MI (upper peninsula) and broadly across Ontario, Alberta, Manitoba and Saskatchewan. Moves through the Great Plains and Mississippi Valley to wintering grounds in e TX (south to Brownsville and w to Edwards Plateau), e OK, AR, MS, central and s MO, s Ill, w TN, w KY, se KS, LA, n FL (panhandle and sparingly farther south), w and s AL, Coastal Plain of GA and SC. Timing: Spring migration occurs from Mar-May, with first birds arriving in ND during first week of May and with peak arrival in mid-May (Murray, B. 1969). Birds leave breeding grounds in mid- Sep- early Oct and arrive in GA as early as Oct 7 with most birds arriving in early Nov. Most of specimens collected in Charleston, SC were female, indicating that females may winter farther south than males (McNair and Post 2000) (Lowther, P. 2005). Identification: A small (L 5 in; WS 6.5 in; WT 0.46 oz) (Sibley, D. 2000) sparrow of grasslands, prairies, wet fields and marshes. Most often seen in flight, going away. Flight is reluctantly undertaken as the species prefers to evade intruders by "creeping around like mice under mats of grass" (Mengel 1965) and only takes flight to avoid being stepped on. Flight is weak, just over the top of the grass, covering a very short distance before the bird drops back to the ground and melts into the grass. The bird often runs several meters upon alighting, making relocation by observers very difficult. In flight, LeConte's appears very light in color and small with a long, sharp tail feathers. Tail is fanned in flight and appears to be rounded because outer rectrices are shorter than middle rectrices. When pressed, it may perch low and motionless in a small tree or bush on the field edge. Distinctly pale and brightly patterned overall (Sibley 2000). Head pattern distinctive. Face, including supercilium and malar, is bright ochre with light grayish auricular patch and lores. Crown is blackish with a white median crown stripe that distinguishes it from similar species. Nape light grayish with fine purplish or chestnut streaks. Eye dark with thin whitish eye-ring. Bill small and pinkish. Post-ocular stripe black, and a small black spot is often seen at the posterior end of the auricular patch. Black malar stripe is faint and can be absent. Back has scalloped appearance, with three wide, dominant black streaks running the length of the back and outlined in white. Black feathers of wing coverts edged in rufous and buff, and tertials black with white edges. Throat, breast, sides and flanks ochre. Breast has a few thin black streaks or is unstreaked. Sides and flanks heavily streaked with black. Legs and tarsi pink. Belly bright white. Tail almost as long as wing, and tail feathers very narrow and pointed. In GA may be confused with Grasshopper Sparrow ( A. savannarum ), Henslow's Sparrow (A. henslowii) or Nelson's Sharp-tailed Sparrow (A. nelsoni), all of which can occur in similar habitats. Adult LeConte's can be distinguished from all three of these sparrows by its extensively ochre (orangey) face, throat, breast, sides and flanks, white belly and lack of breast streaking (but with heavy streaking on sides and flanks), weak gray auricular patch, fine purplish or pinkish streaks on grayish nape, white median crown stripe, and absent or weak malar stripe (Lowther, P. 2005). Most often confused in GA with Grasshopper Sparrow, which has a large, flat bill, and only a spot of ochre in the lores and below the auricular but has a gray supercilium. In GA, confusion with A. nelsoni is less common since nelsoni usually occurs in salt marshes, a habitat from which LeConte's is absent. Occasionally, nelsoni is found in freshwater marshes in GA, but it's gray median crown stripe and lack of pinkish stripes on the nape separate it from LeConte's. Conservation: Scant information available regarding population estimates and trends due to detection difficulty. Based on 135 BBS routes across its breeding range, the species increased by 29.8% from 1984-1993 (Price et al., 1993). The Ontario breeding bird atlas project estimated 11-100 pairs/100 square km for blocks along central areas of James Bay Coast (Cadman et al., 1987), the area likely supporting the greatest number of breeding LeConte's Sparrows (J. Rising, pers. comm.). Overall population numbers likely to fluctuate according to local conditions, with more birds in wet years than in dry years (Knapton 1979). In n. Great Plains in Conservation Reserve Program fields, during a drought period from 1990-1993, only 12 breeding pairs were found (mean density 0.04 pairs/ 100-ha). During the period of above average precipitation from 1994-1996, breeding pairs numbers increased sharply. Surveys found 290 breeding pairs in 1994 (5.4 pairs / 100-ha), 1140 pairs in 1995 (21.2 pairs / 100-ha), and 1140 pairs in 1996 (21.8 pairs / 100-ha) (Ingl and Johnson 1995, 1996.) Most abundant in s TX during wettest year of three year study (Grzybowski 1980). Threats include annual cutting of hay fields in breeding range and annual burning of fields. Populations benefit from periodic cutting and burning of fields, which establish lusher ground cover and eliminate woody growth (Lowther, P. 2005). Literature Cited: Brewer, G.A. McPeak, R.J. Adams, Jr. 1991. The atlas of breeding birds of Michigan. Michigan State Univ. Press. East Lansing. Cadman, M.D., P.F. J. Eagles and F.M Helleiner. 1987. Atlas of Breeding Birds of Ontario. Univ. of Waterloo Press. Waterloo. Cooper, S. 1984. Habitat and size of the LeConte's Sparrow territory. Loon 56: 162-165. Easterla, D.A. 1962. Foods of LeConte's Sparrow. Auk 79: 272-273. Grzybowski, J.A. 1980. Ecological relationships between grassland birds during winter. PhD diss. University of Oklahoma, Norman. Knapton, R.W. 1979. Birds of Gainesborough-Lyleton region (Saskatchewan and Manitoba). Saskatchewan Nat. Hist. Soc. Spec. Publ. no. 10. Letourneau, V. and Y. Aubrey 1996. LeConte's Sparrow, pp. 990-993. In The breeding birds of Quebec: Atlas of breeding birds of southern Quebec (J. Gauthier and Y. Aubrey, eds.) Association des groupes ornithologues, P.Q. Soc Protection of Birds, CWS Montreal, PQ. Lowther, Peter E. 2005. LeConte's Sparrow (Ammodramus leconteii), The Birds of North America Online (A.Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: <http://bna.birds.cornell.edu.bna/species/224. Murray, B.G., Jr. 1969. A comparative study of LeConte's and Sharp-tailed Sparrow, Auk 86:199-231. Peabody, P.B. 1901. Nesting habits of LeConte's Sparrow. Auk 18: 129-134. Semenchuk, G.P. 1992. The atlas of breeding birds of Alberta. Fed Alberta Nat., Edmonton.
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