Explanation of Howard County Atlas Data

Photo of bird 1 Name of bird Results of 2002-2006 Atlas 2
Map of Howard County with Blocks & Quarterblocks legend Results of 1983-1987 Atlas 3
Names of Topographic Quadrangles & Blocks     The Grid. The national topographic maps in North America are based on degrees of latitude and longitude. When a 7 1/2 minute topographic map is subdivided into sixths (each block having 2 1/2 degrees of latitude and 3 3/4 degrees of longitude) the area of each such block at the latitude of Maryland is almost exactly the same (within 3/10 of 1%) as that of a 5-km square. Howard County is again one of the Maryland counties in which each block is further divided into quarter-blocks measuring about 2.5 by 2.5 km. The main purpose of the finer grid is to more easily detect changes in bird distribution in future years.
    Breeding Categories. See Second Maryland/DC Breeding Bird Atlas Project Handbook for an explanation of the breeding criteria and codes (available on the MOS Atlas page). These are the breeding categories used:

  blackrec (1K) Confirmed  P Probable  + Possible  o Observed
Results of 1973-1975 Atlas 4

1. Not all pages have a photo. The logo for Maryland/DC Breeding Bird Atlas Project (MAP) appears on the pages without a photo. The photos also appear on the Howard County Bird Club photo page or are part of the Howard County Bird Club photo collection and are used with permission. Some of these photographs may be copyrighted by the photographer. Before reproducing or using any of these photographs, contact the photographer for permission. If you are unable to contact the photographer directly, send an email to the Howard Bird Club with the necessary information, and we will forward it to the photographer.

Photographs are by (bird name - photographer): Canada Goose - June Tveekrem; Mute Swan - Kevin Heffernan; Wood Duck - Jeff Metter; Gadwall - Ralph Cullison; American Wigeon - Jeff Metter; American Black Duck - Bill Hill; Mallard - Ralph Cullison; Blue-winged Teal - Kurt Schwarz; Redhead - Ralph Cullison; Ring-necked Duck - June Tveerkem; Hooded Merganser - Mark Hollis; Ruddy Duck - June Tveekrem; Ring-necked Pheasant - Scott Berglund; Wild Turkey - Scott Berglund; Northern Bobwhite - Jeff Metter; Pied-billed Grebe - June Tveekrem; Double-crested Cormorant - Ralph Cullison; American Bittern - Ralph Cullison; Least Bittern - Jeff Metter; Great Blue Heron - Ralph Cullison; Great Egret - Scott Berglund; Green Heron - Jeff Metter; Black-crowned Night-Heron - Kevin Heffernan; Yellow-crowned Night-Heron - Michelle Stewart; Glossy Ibis - Ralph Cullison; Black Vulture - Ralph Cullison; Turkey Vulture - Lauri Lee; Osprey - Kurt Schwarz; Bald Eagle - Bart Pitts; Northern Harrier (no photo); Sharp-shinned Hawk - June Tveekrem; Cooper's Hawk Scott Berglund; Red-shouldered Hawk - Kurt Schwarz; Broad-winged Hawk (no photo); Red-tailed Hawk - Kurt Schwarz; American Kestrel - June Tveekrem; King Rail (no photo); Virginia Rail - June Tveekrem; Sora - Barry Miller; Common Moorhen - Ralph Cullison; American Coot - June Tveekrem; Killdeer - Ralph Cullison; Spotted Sandpiper - Ralph Cullison; Upland Sandpiper - Ralph Cullison; American Woodcock - HCBC slide show; Least Tern (no photo); Rock Pigeon (no photo); Mourning Dove - Ralph Cullison; Black-billed Cuckoo (no photo); Yellow-billed Cuckoo - Scott Berglund; Barn Owl - Kurt Schwarz; Eastern Screech-Owl - Kathy Colston; Great Horned Owl - Ralph Cullison; Barred Owl - Ralph Cullison; Common Nighthawk - Jeff Friedhoffer; Whip-poor-will (no photo); Chimney Swift - Ralph Cullison; Ruby-throated Hummingbird - Ralph Cullison; Belted Kingfisher - Ralph Cullison; Red-headed Woodpecker - Gayle & Bill Hill; Red-bellied Woodpecker - Jeff Metter; Downy Woodpecker - Ralph Cullison; Hairy Woodpecker - Kevin Heffernan; Northern Flicker - Ralph Cullison; Pileated Woodpecker - Ginny Walker; Eastern Wood-Pewee - Ralph Cullison; Acadian Flycatcher - Kevin Heffernan; Alder Flycatcher (no photo); Willow Flycatcher - Ralph Cullison; Least Flycatcher (no photo); Eastern Phoebe - Kurt Schwarz; Great Crested Flycatcher - Ralph Cullison; Eastern Kingbird - Jeff Metter; White-eyed Vireo - Jeff Metter; Yellow-throated Vireo - Ralph Cullison; Blue-headed Vireo - Barry Miller; Warbling Vireo - Ralph Cullison; Red-eyed Vireo - Ralph Cullison; Blue Jay - Ralph Cullison; American Crow - Ralph Cullison; Fish Crow - Scott Berglund; Common Raven Scott Berglund; Horned Lark - Gayle & Bill Hill; Purple Martin - Jeff Metter; Tree Swallow - Gayle & Bill Hill; Northern Rough-winged Swallow - Kevin Heffernan; Bank Swallow - June Tveekrem; Cliff Swallow - Ralph Cullison; Barn Swallow - Ralph Cullison; Carolina Chickadee - June Tveekrem; Tufted Titmouse - June Tveekrem; Red-breasted Nuthatch - June Tveekrem; White-breasted Nuthatch - Kevin Heffernan; Brown Creeper - Jeff Metter; Carolina Wren - Kevin Heffernan; House Wren - Scott Berglund; Blue-gray Gnatcatcher - Ralph Cullison; Eastern Bluebird - Barry Miller; Veery - Ralph Cullison; Wood Thrush - Ralph Cullison; American Robin - Ralph Cullison; Gray Catbird - Ralph Cullison; Northern Mockingbird - Ralph Cullison; Brown Thrasher - Ralph Cullison; European Starling - Kevin Heffernan; Cedar Waxwing - Jeff Metter; Blue-winged Warbler (no photo); Northern Parula - Ralph Cullison; Yellow Warbler - Ralph Cullison; Chestnut-sided Warbler - Ralph Cullison; Yellow-throated Warbler - Ralph Cullison; Pine Warbler - Kevin Heffernan; Prairie Warbler - Ralph Cullison; Cerulean Warbler - Ralph Cullison; Black-and-white Warbler - Kevin Heffernan; American Redstart - Ralph Cullison; Prothonotary Warbler - Ralph Cullison; Worm-eating Warbler (no photo); Ovenbird - Kevin Heffernan; Louisiana Waterthrush - Scott Berglund; Kentucky Warbler - Ralph Cullison; Common Yellowthroat - Ralph Cullison; Hooded Warbler - Barry Miller; Yellow-breasted Chat - Ralph Cullison; Summer Tanager - Scott Berglund; Scarlet Tanager - Ralph Cullison; Eastern Towhee - Ralph Cullison; Chipping Sparrow - Ralph Cullison; Field Sparrow - Scott Berglund; Vesper Sparrow - Ralph Cullison; Savannah Sparrow - Ralph Cullison; Grasshopper Sparrow - Ralph Cullison; Henslow's Sparrow - Kurt Schwarz; Song Sparrow - June Tveekrem; Swamp Sparrow - Ralph Cullison; Northern Cardinal - Ralph Cullison; Rose-breasted Grosbeak - Ralph Cullison; Blue Grosbeak - Ralph Cullison; Indigo Bunting - Ralph Cullison; Dickcissel - Ralph Cullison; Bobolink - Ralph Cullison; Red-winged Blackbird - Ralph Cullison; Eastern Meadowlark - Ralph Cullison; Common Grackle - Jeff Metter; Brown-headed Cowbird - Ralph Cullison; Orchard Oriole - Ralph Cullison; Baltimore Oriole - Kevin Heffernan; House Finch - Ralph Cullison; American Goldfinch - Jeff Metter; House Sparrow- Scott Berglund.

2. Material is compiled from the Howard County Bird Club's "Breeding Bird Atlas" database and has been cross-checked with the USGS North American BBA Explorer "Maryland & DC 2002-2006" atlas material.

3. Compiled from Maryland Department of Natural Resources original atlas material for the Atlas of the Breeding Birds of Maryland and the District of Columbia published in 1996. The atlas material for 1983-1987 is included in the "Maryland & DC 2002-2006" atlas cited above and is independently used for the Howard County Bird Club's "Breeding Bird Atlas" database.

4. Compiled from original data for the Breeding Bird Atlas of Howard County (1973-1975), the first to use quarter-blocks. Data is in the Howard County Bird Club's "Breeding Bird Atlas" database. Some species have a chart with the number of quarter-blocks confirmed, probable, and possible for the 1973-1975 atlas but do not have the results shown on the map for each quarter-block. (Available original material does not include all map detail for these species.) The results of the Howard County 1973-1975 atlas were published in Maryland Birdlife 43(1): 3-39.