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F.M. Uhler

Publications and source records attributed to F.M. Uhler.

At least 19 recordsLinked to original sources
USGS1988

Food habits and distribution of wintering canvasbacks, Aythya valisineria, on Chesapeake Bay

Baltic clams ( Macoma balthica ) were the predominant food items of 323 canvasbacks ( Aythya valisineria ) collected throughout Chesapeake Bay during 1970–1979. Natural vegetation constituted 4% of the food volume. Widgeongrass ( Ruppia maritima ) and redhead grass ( Potamogeton perfoliatus ) constituted the greatest percent volume and frequency of occurrence among the plant species, whereas wild celery ( Vallisneria americana ) constituted only a trace of the food volume. These results contrast with historical records of food habits of canvasbacks in Chesapeake Bay. Canvasback population estimates during the 1970’s were examined to detect annual and seasonal changes in distribution. Linear regression analyses of winter canvasback populations in the bay showed a significant decline in the upper-bay and middle-bay populations, but no significant changes in the lower-bay and Potomac River populations. The changes in winter distribution and abundance of the canvasback appear related to changes in natural food availability, which is the result of altered environmental conditions.

Maryland, Virginia↗
USGS1982

Food habits of diving ducks in the Carolinas

Food habits analyses were conducted on 264 diving ducks (7 species) from North and South Carolina during the 1970'S. The Baltic clam (Macoma balthica) was the predominant food among canvasbacks (Aythya valisineria) from the Pamlico River area, whereas sago pondweed (Potamogeton pectinatus) predominated in birds from impoundments in North and South Carolina. Shoalgrass (Halodule beaudettei) formed 100% of the gullet food and 99% of the gizzard food in redheads (Aythya americana) from Pamlico Sound. Lesser scaup (Aythya affinis) in North Carolina had fed predominantly on mollusks (Mulinia lateralis and Rangia cuneata), whereas widgeon grass (Ruppia maritima) was the predominant food in birds from South Carolina. In North Carolina, ring-necked ducks (Aythya collaris) fed mainly on vegetation, and greater scaup (Aythya marila), bufflehead (Bucephala albeola), and ruddy ducks (Oxyura jamaicensis) fed mainly on Mulinia lateralis. Food habits data from this study when compared with historical food habits of these species indicate that most diving duck species were feeding more on invertebrates and less on submerged aquatic vegetation than in the past. North and South Carolina have a diverse food supply and appear to offer waterfowl adequate wintering habitat based on these food habits studies. Present trends in wintering habitat, however, could adversely affect diving duck populations in the future.

Proceedings of the Annual Conference of the Southe↗
USGS1981

Asiatic clam (Corbicula manilensis) and other foods used by waterfowl in the James River, Virginia

Corbicula manilensis was found in the gizzards of 24 ducks of 5 species taken from the James River, Virginia, between 1973 and 1976. Percent average volume in these species ranged from trace to 6%. This is the first known occurrence of this exotic clam in the food of duck in Chesapeake Bay. A total of 135 other food items was identified from the 116 gizzards of 9 species that were examined. Food that predominated included Cyperus spp., Leersia oryzoides, Polygonum spp., and Zea mays . The great diversity of food consumed in this fresh tidal section of the James River indicates the high value of these wetlands to waterfowl.

Virginia↗
USGS1967

Magruder Park Swamp

The last Tuesday in August, between five-thirty and seven in the evening, we zigzaged through this glorious jungle, attended by a family of Wood Pewees for whom we seemed to be stirring up a feast of flying insects. There was gentle background music by Mole Crickets. A few steps in from the playing field and we were out of sight in ten-foot-high Cattails. All through, we met -- as high as we, or higher--clumped Cinnamon Ferns, deep-rose Joe Pye Weed, and orange, pendent flowers of Jewelweed (first cousins to Balsam and Sultana). Here and there were soft, white spikes of Canadian Burnet, a rare plant hereabouts, and deep purple Ironweed. Dense-foliaged Hempweed climbed over bushes and up small trees, filling the air with its delicate fragrance. Arrowleaf Tear-thumb snatched at us with tiny prongs on its angled stems. Once in a while we tripped over huge sedge tussocks, half-hidden in the tangle. A few times we steered around a small bush of Poison Sumac. The next day We remembered seeing ninety kinds of plants on this hasty trip. Skunk Cabbage leaves recalled April, when a person, from the edge of the lawn, could see huge clumps of them all the way across the swamp. The sky had been washed by last week's downpours; scattered Gums were reddening; and Maples were getting ready for crimson beauty a month from now. There wasn't a mosquito! (Ed. Note.-The Hyattsville City Council is taking pains to preserve this interesting swamp.)

Prince Georges Post↗
USGS1964

Water off and on

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Book chapter↗
USGS1956

New habitats for waterfowl

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Transactions of the North American Wildlife Confer↗
USGS1951

In Memoriam: Albert Kenrick Fisher

Dr. Albert Kenrick Fisher, a Founder and Past President of the American Ornithologists' Union and one of its best known Fellows for nearly 65 years, died in Washington, D. C. on June 12, 1948, after a brief illness from circulatory complications that developed as a result of advanced age. With his passing, the American Ornithologists' Union has lost one of its last links with that eminent group of bird students who founded this organization in the autumn of 1883.

The Auk↗