Eastern Meadowlark Sturnella Magna
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Eastern Meadowlark Sturnella magna Breeding Eastern Meadowlarks are normally associated with Unglaciated Plateau (94 blocks), and Glaciated Plateau (69 grasslands such as lightly grazed pastures, hayfields, and re- blocks) regions. Other confirmation included observations of claimed strip mines. These fields may be devoid of woody adults carrying food for young in 96 blocks, 49 reports of recently vegetation or support scattered bushes and small trees. They also fledged young, 41 active nests, and distraction displays by adults regularly occupy fallow fields composed of mixed grasses and in 9 blocks. Most other records pertained to probable breeders, weeds, grassy rights–of–way along highways and railroads, primarily territorial males and pairs occupying suitable habitats. clover–alfalfa hayfields, and grassy fields bordering airports. When their populations were larger, breeding pairs were found in cultivated grain fields, woodland clearings, and fairly open brushy thickets (Trautman 1940), but these habitats are rarely occupied today. These meadowlarks have been common and widely distrib- uted summer residents in Ohio since the 19th century (Wheaton 1882, Jones 1903). They retained this status into the 1930s when Hicks (1935) claimed they were common to abundant in every county. He assigned a similar status to this species along the entire unglaciated Allegheny Plateau (Hicks 1937). Beginning in the 1940s, Eastern Meadowlark populations experienced local declines. This trend continued during subsequent decades as intensive agricultural land use practices eliminated many suitable grasslands (Peterjohn 1989a). Unusually heavy mortality during the severe winters of the late 1970s accentuated this decline, although their numbers recovered somewhat with the return of normal winter weather conditions. Declining numbers are not limited to Ohio but have been evident throughout eastern North America since 1965 (Robbins, C. S., et al. 1986). Despite their declining numbers, Eastern Meadowlarks remain widespread summer residents in Ohio. The Atlas Project pro- duced records from 738 priority blocks (96.6% of the statewide total) within every county. They were nearly equally distributed Alvin E. Staffan in each physiographic region with records from 89.5–99.6% of the regional priority blocks. Breeding pairs proved to be locally scarce only within large urban areas and on heavily forested Meadowlark nests are invariably placed on the ground, portions of the unglaciated Allegheny Plateau. The relative usually in shallow depressions under clumps of dense grasses. abundance of Eastern Meadowlarks on Breeding Bird Surveys While courtship behavior has been observed during March exhibits a different pattern. They are most numerous in the (Williams 1950), nest construction does not normally begin until Illinoian Till Plain region, although the small number of routes in the second half of April in southern and central Ohio and early this region may overestimate their relative abundance in south- May along Lake Erie. The earliest published egg date is April 25 western Ohio. Their numbers decline somewhat in the Till Plain (Price 1935), although earlier dates are likely in the southern region, while even smaller numbers are recorded on surveys counties. Most first clutches are produced during the first half of along the Allegheny Plateau. The fewest breeding meadowlarks May. Fledglings have appeared as early as May 16 (Trautman are found on the Lake Plain where urbanization and intensive 1940), but most first broods do not fledge until June 10–25. agricultural activities have eliminated many suitable grasslands. Eastern Meadowlarks normally raise two broods annually and Breeding Eastern Meadowlarks were confirmed in 69.9% of frequently renest if their first attempt fails. These late attempts all the priority blocks they were found in. The “30” code was are responsible for nests with eggs through July 10 and fledg- used to confirm nesting in 317 of these blocks. This code was lings into the first half of August. An exceptionally late nest most frequently utilized in the Till Plain (121 blocks), produced recently fledged young on August 26 (Peterjohn 1989a). 362 Blocks Special Areas Other Observations Confirmed Probable Possible Analysis of Block Data by Physiographic Region Summary of Total Blocks % Regional Ave. # Individ Breeding Status Physiographic Blocks with with % per BBS Route No. of Blocks in Which Region Surveyed Data Data for Ohio (1982–1987) Species Recorded Lake Plain 95 85 89.5 11.5 7.2 738 96.6% Till Plain 271 270 99.6 36.6 17.8 Total Ill. Till Plain 46 43 93.5 5.8 26.5 Confirmed 516 69.9% Glaciated Plateau 140 137 97.9 18.6 13.6 Probable 210 28.5% Unglaciated Plateau 212 203 95.8 27.5 12.2 Possible 12 1.6% 363 Eastern Meadowlark.