White-winged Scoters Research Articles

Nesting Biology of the White-Winged Scoter

Nesting biology and productivity of white-winged scoters (Melanitta fusca deglandi) were studied on islands in Redberry Lake, Saskatchewan, and Jessie Lake, Alberta, in 1975-76. Males constituted 60% of the prenesting populations. Nest initiation peaked between 8 and 21 June, and most nests were under dense shrubs at least 50 m from the nearest shoreline. The mean laying rate for 8 females was 1 egg every 34.4 hours, and mean clutch size (N = 146) was 9.17. The average incubation period for 22 clutches was 27.7 days, and 80% of all clutches hatched between 17 and 31 July. Nesting success averaged 72%. Aggregate broods formed in late July and most hens deserted their broods between 10 and 23 August. Small, mixed-age broods were common after 21 August, and total number of ducklings declined markedly thereafter. Productivity was less than 1.0 ducklings/pair on both lakes in 1976. J. WILDL. MANAGE. 45(1):38-45 White-winged scoter populations have declined in the parklands and boreal forests of northern Alberta, and in coastal and interior Alaska (Bellrose 1976:404). A dramatic decline also has occurred in southwestern Manitoba. The reasons for these declines are not known because scoters are among the least-studied waterfowl groups (Bellrose 1976:408-409), and little information is available concerning their reproductive biology. Clutch sizes have been reported for few whitewinged scoter nests (Bent 1925:132-133, Rawsl 1949:84-88, Vermeer 1969), and no information has been published on brood survival in North America. The objective of our study was to provide information on the nesting biology and productivity of white-winged scoters. Without the encouragement and assistance of F. C. Bellrose, this project would not have been initiated. We also thank L. B. Best, R. B. Dahlgren, R. D. Drobney, and L. H. Fredrickson for their reviews of the manuscript; C. E. Harris for help in the field in 1975; and R. D. Crawford, D. C. Morgan, M. R. Ryan, and D. White for their help. The Iowa Cooperative Fishery Research Unit provided a boat and motor in 1975. K. Vermeer, B. Rippen, and C. S. Houston recommended study areas.

Longevity of White-Winged Scoters

Longevity of White-Winged Scoters

A Pleistocene Record for the White-Winged Scoter in Maryland

A Pleistocene Record for the White-Winged Scoter in Maryland

Food‐Habitat Relationship of Sea Ducks on the New Hampshire Coastline

Use of habitat, food preferences, and food availability were studied for seven species of waterfowl (white—winged scoter (Melanitta deglandi), surf scoter (M. perspicillata), common scoter (Oidemia nigra), oldsquaw (Clangula hyemalis), common goldeneye (Bucephala clangula), bufflehead (B. albeola), and red—breasted merganser (Mergus serrator)) on a 34—km section of the New England coastline during 1968—70. The three scoters selectively used areas of sandy substrate and had very similar food habits. The principal foods were the Atlantic razor clam (Siliqua costata) and Arctic wedge clam (Mesodesma arctatum), which were characteristic of, and abundant in, sandy substrate. In contrast to scoters, goldeneye preferred areas of rocky substrate associated with rocky headlands. They fed primarily on amphipods, isopods, crabs, and gastropods, which were commonly found in the Irish moss (Chondrus crispus) covering of the rocky sublittoral areas. Red—breasted mergansers, like goldeneye, also used the rocky areas. They fed primarily on several small fish species that were observed among the Irish moss and crevices of the rocky substrate. Bufflehead had the most restrictive distribution, being confined mostly to estuaries. Bufflehead fed primarily on sand shrimp, which were found only in harbors with soft ooze bottoms. Oldsquaw had the most generalized diet of all the sea ducks. The major food items consisted of bivalves, gastropods, sand shrimp, and isopods, which were found throughout the study area and accounted for the generalized distribution of oldsquaw along the coastline and in the harbors. Sea ducks were concentrated near the mouths of the estuaries, where more abundant food resources particularly bivalves, were found. Although the species vary, the types of foods eaten by sea ducks were similar to those described in other studies. Thus, food availability, coupled with the physical structure of the substratum in the different coastal habitats, is apparently a major determinant in the way that coastal waterfowl selectively use habitat types. The described patterns of habitat usage appear to have implications for other wide geographical areas.

Food Habits of the White-Winged Scoter in Northwestern California

Food Habits of the White-Winged Scoter in Northwestern California

Differential Vulnerability Patterns among Three Species of Sea Ducks

During the 1969 and 1970 hunting seasons, 1,530 white-winged scoters (MeZanitta deglandi), surf scoters (M. perspicilla;ta), and common scoters (Oidemia ntgra) were observed responding to decoys in typical scoter hunting situations on the New Hampshire coastline. Results indicated that the common scoter was extremely vulnerable to actual hunting, the surf scoter was intermediate, and the white-winged scoter was the least vulnerable. These differences in vulnerability patterns influenced the composition of the scoter harvest as compared with the relative abundance of the three species on the study area. The literature indicates that changes in population levels and winter distribution of scoters have occurred. The described differences in vulnerability, coupled with past hunting pressure, provide a mechanism by which these changes could have happened. To more fully understand the future dynamics of scoter populations in relation to harvest, more accurate population measurements are needed. The sport of sea duck hunting is old and well established, especially along the New England coast, and many hunters enjoy the challenge of ocean shooting with the long seasons and liberal bag limits. Despite this long history of sport hunting, there is little available information concerning the effect of hunting on sea duck populations because of the presently inadequate sampling of the harvest by such surveys as wing collections, hunter mail questionnaires, and band recovery data. Differences in vulnerability of waterfowl, based on observations in hunting situations, were first described in 1965 (Olson 1965). From this work, Olson concluded that disproportionate sex ratios in canvasbacks ( Aythya valisiner?a ) were the result of differences in vulneralbility between sexand age-groups. He further suggested that differences in vulnerability probably affected the population structure of other waterfowl such as lesser scaup ( Aythya

An Evaluation of Waterfowl Surveys on the New Hampshire Coastline

An Evaluation of Waterfowl Surveys on the New Hampshire Coastline

Eucotyle castanea n.sp. and other trematodes of the family Eucotylidae from birds in British Columbia

Four species of trematodes of the family Eucotylidae were collected from birds in British Columbia. Eucotyle castanea n.sp. from Melanitta deglandi (Bonaparte) differs from other members of the genus mainly by the presence, throughout its parenchyma, of a reddish-brown pigment. E. cohni Skrjabin, 1924 was recovered from Podiceps grisegena holböllii Reinhardt, Clangula hyemalis (Linnaeus), Bucephala clanguia (Linneaus), and Padiceps aurittis (Linnaeus). E. warreni Schell, 1967 was collected from Bucephala islandica (Gmelin) and Tanaisia fedtschenkoi Skrjabin, 1924 from Charadrius vociferus Linnaeus. This is the first record of the occurrence of these parasite species in Canada.The structure of the cirrus sac in E. castanea and E. cohni and the excretory system of the latter species are described. The relationship between Eucotyle and Tanaisia is discussed and a key to the species of Eucotyle is included.

An Outbreak of Fowl Cholera in Waterfowl on the Chesapeake Bay

An outbreak of fowl cholera (Pasteurella multocida infection) occurred in waterfowl wintering on the Chesapeake Bay during February to March 1970. Losses were primarily confined to sea ducks: oldsquaws (Clangula hyemalis), white-winged scoters (Melanitta deglandi), goldeneyes (Bucephala clangula), and buffleheads (Bucephala albeola).

Some Aspects of the Breeding of the White-Winged Scoter at Miquelon Lake, Alberta

Some Aspects of the Breeding of the White-Winged Scoter at Miquelon Lake, Alberta

On the environment of Polymorphus minutus (Acanthocephala) in ducks.

Crompton & Harrison (1965) complied from the literature a list of 84 species of bird which have been reported to be final hosts ofPolymorphus minutusand since then, the parasite has been found in the American White-winged Scoter (Melanitta deglandi) and the Chestnut Teal (Anas castanea) by Schmidt (1965) and Avery (1966) respectively. Unless detailed investigations are undertaken, there is no way of knowing how many of these birds from true hosts in whichP. minutuscan reproduce successfully.P. minutushas also been reported from the muskrats (Ondata zibethica) which Golvan (1961) considered to be an accidental host and I have recovered seven living specimens ofP. minutus48 h after forcibly feeding 20 cystacanths of the parasite contained inGammarus pulexto a female Wistar rat. The seven worms were firmly attached to the rat's intestinal wall and all were located in the posterior half of the intestine.

TAXONOMIC AND BIOLOGICAL OBSERVATIONS ON STREPTOCARA CALIFORNICA (GEDOELST, 1919) GEDOELST AND LIÉGEOIS, 1922 AND THE GENUS STREPTOCARA (NEMATODA: ACUARIIDAE)

A detailed redescription is presented for adults of Streptocara californica (Gedoelst, 1919) Gedoelst and Liégeois, 1922 based on specimens from under the gizzard lining of a common scoter, Oidemia nigra (L.), from Vancouver, Canada. Adult S. californica are here reported from the type host, Melanitta deglandi (Bonap.), and from the following new hosts near Vancouver: Anas platyrhynchos L., Aythya valisineria (Wilson), Bucephala islandica (Gmelin), Clangula hyemalis (L.), Melanitta perspicillata (L.), and Mergus serrator L. A description of the fourth-stage larvae is presented, based on specimens from Aythya marila (L.), Melanitta perspicillata (L.), and Mergus merganser L. from the same region. Yseria californica Gedoelst, 1919; Korjakinema gusi Oschmarin, 1950; Streptocara dogieli Belopolskaya, 1952; and Skrjabinobronema californicum (Gedoelst, 1919) Yamaguti, 1961 are considered synonyms of Streptocara californica. A comparison of the prevalence of S. californica with that of S. crassicauda charadrii Skrjabin, 1916 seems to indicate rather different life cycles for the two species. It is suggested that the genus Streptocara may be more highly evolved than the other genera of the Seuratiinae.

A White-Winged Scoter Specimen from Alabama

A White-Winged Scoter Specimen from Alabama

White-Winged Scoter Banding

White-Winged Scoter Banding

Naming Wild Birds as If They Were Poultry

As FOLK names are of multifarious origin and are never compiled or systematized by the people, the diversity of the cock, hen, pullet, and related titles indicates a wide prevalence of the conceit of naming birds as if they were wild poultry. In its extreme form, this fancy results in comparisons with a particular breed of fowls. When a Wisconsin farmer spoke, although facetiously, of his black manorkies, he referred to the crows on his place as if they were a kind of chicken (Minorca). Then too, if I am not mistaken, the name coachen (varied to coachin, and folk-etymologized as cold-shin) in coastal North Carolina really means 'Cochin,' and indicates that the wildfowl specified (greater and lesser scaups and the ring-necked duck) are thought of as breeds of Nature's poultry. Further, when even the little downy woodpecker in the neighborhood of Golden Pond, Kentucky, is called dominecker, the allusion is to its speckled plumage, suggesting that of a race of chickens, the Dominique, which a long time ago some of us learned to call the dominick or dominicker. A related christening is that of dominicker for the red-shouldered hawk in Georgia. In this type of folk naming, the domesticated varieties of ducks also are not wholly neglected, the large Muscovy, with distinctive head adornment, suggesting the scoters, sizable among wild ducks and with unusually shaped and colored bills. All of our three species are known as bay muscoveys in Maryland, and each has been recorded under cognate but distinct titles: the white-winged scoter as muscovy (Pa.) and muscovite (Iowa); the surf scoter as 'scovy (Va.) and wild muscovy (Pa.); and the black scoter as little muscovy (Pa.). Surprisingly, the cognomen guinea is not as a rule applied to spotted birds; if there is any tendency in the usage, it is to designate medium-sized species that may more or less logically be classed as wild poultry. Spots seem to have been the decisive factor in giving the simple appellation guinea to Mearn's quail (Ariz.), but in all the other examples different reasons appear probable. A list follows:

White-Winged Scoter Nesting Record in North Dakota

White-Winged Scoter Nesting Record in North Dakota

Summer Occurrence of the White-Winged Scoter on National Wildlife Refuges

Summer Occurrence of the White-Winged Scoter on National Wildlife Refuges

Status of the White-Winged Scoter in Louisiana

Status of the White-Winged Scoter in Louisiana

The White-Winged Scoter in Louisiana

The White-Winged Scoter in Louisiana