Louis N. Locke

The occurrence of lead in tissues of wild birds

Lead poisoning has been recognized as a factor in waterfowl mortality since the turn of the century. Lead, once believed to be foreign, or accidental at most in its occurrence, is now known to be a regularly occurring constituent of plant and animal tissues. Although there is a relatively large amount of information on the concentration of lead in tissues of birds that have succumbed to lead poisoning, there is a conspicuous need for a record of naturally occurring levels in certain tissues. All birds are constantly exposed to sublethal quantities of lead in their food. Such exposure results in measurable amounts in the bones, soft tissue, and liver. No biological requirement for lead has been established.

Lead poisoning in a sample of Maryland mourning doves

A sick mourning dove (Zenaidura macroura) collected in Maryland with 2 lead shot in the gizzard showed acid-fast intranuclear inclusion bodies in the kidney tubular cells. The liver and the tibia contained 72 ppm and 187 ppm lead (wet weight) respectively. Four gizzards from 62 doves killed by hunters contained lead shot. The lead content of 43 dove livers ranged from 0.4-14.0 ppm (wet weight); 40 of these doves were collected by hunters, and the other 3 were dying of trichomoniasis.

Brain lesions in mallard ducklings from parents fed methylmercury

Methylmercury dicyandiamide was fed to mallard ducks at 3 ppm mercury. Mercury accumulated in the eggs to an average of 7.18 and 5.46 ppm on a wet-weight basis in 2 successive years. Mercury in the eggs is believed to have caused brain lesions in the hatched ducklings. Lesions included demyelination, neuron shrink-age, necrosis, and hemorrhage in the meninges overlying the cerebellum. Brains of dead ducklings contained an average of 6.17 and 5.19 ppm mercury on a wet-weight basis in 2 successive years.

Lead poisoning in Canada geese in Delaware.

483 geese died at the Bombay Hook Wildlife Refuge between November 1965 and April 1966. All but one goose had enough lead in the liver to indicate lead poisoning as the cause of death. Delaware waterfowl biologists have estimated that perhaps as many as 2000-4000 geese succumbed to what appears to be lead poisoning during the winter of 1965-66. 9 references, 3 figures, 2 tables.

Lead in tissues of mallard ducks dosed with two types of lead shot

SummaryMallard ducks (Anas platyrhynchos) were sacrificed one month after ingesting one number 4 all-lead shot or one number 4 lead-iron shot. Livers, kidneys, blood, wingbones, and eggs were analyzed for lead by atomic absorption.Necropsy of sacrificed ducks failed to reveal any of the tissue lesions usually associated with lead poisoning in waterfowl. Lead levels in ducks given all-lead shot averaged about twice those in ducks given lead-iron shot, reflecting the amount of lead in the two types of shot. Lead in the blood of ducks dosed with all-lead shot averaged 0.64 ppm, and 0.28 ppm in ducks given lead-iron shot. Lead residues in livers and kidneys of females given all-lead shot were significantly higher than in males. In both dosed groups, lead levels in wingbones of females were about 10 times those in males, and were significantly correlated with the number of eggs laid after dosage. Lead levels in contents and shells of eggs laid by hens dosed with all-lead shot were about twice those in eggs laid by hens dosed with lead-iron shot. Eggshells were found to best reflect levels of lead in the blood.Our results indicate that mallards maintained on a balanced diet and dosed with one lead shot may not accumulate extremely high lead levels in the liver and kidney. However, extremely high lead deposition may result in the bone of laying hens after ingesting sublethal amounts of lead shot as a result of mobilization of calcium from the bone during eggshell formation.

Lead Poisoning in Common Loons (Gavia immer)

Two emaciated common loons (Gavia immer) were believed to have died of lead poisoning when fragments of fishing lines and lead sinkers were discovered in their stomachs. Later a third emaciated loon, which had only the remnants of fishing line in its stomach, was suspected of being a possible lead-poisoning victim when all other test results were negative. The liver lead levels in the first two loons were 20.6 ppm and 46.1 ppm (wet weight), and the level in the third was 38.52 ppm (wet weight). Thirteen common loons dying of other causes had liver lead levels of less than 1 ppm (wet weight).

Isolation of poxvirus from debilitating cutaneous lesions on four immature grackles (Quiscalus sp.)

Poxvirus was isolated from nodules on four immature grackles (Quiscalus sp.) collected in two residential areas of Victoria, Texas. All of the birds were emaciated and had nodules on the eyelids, bill, legs, toes, and areas of the skin on the wings, neck, and ventral abdomen. These pox nodules were extensive and probably interfered with both sight and flight. The preliminary diagnosis was confirmed by virus isolation, histopathology, and electron microscopy. Poxvirus was isolated on the chorioallantoic membrane of embryonated hens eggs and in Muscovy duck embryo fibroblast cell culture. Phaenicia calliphoridae (blowfly) larvae were found in one of the pox nodules, raising the possibility of mechanical transmission of the virus by contaminated adult blowflies.

Peregrine falcon suspected of pesticide poisoning

The results of the chemical analysis are shown in Table 1. The falcon weighed 721.5 g and had no deposits of subcutaneous, mesenteric, coronary, or abdominal fat. There were no fractures or injuries present; the myocardium, heart valves, and liver appeared normal. The posterior portions of both lungs appeared consolidated. The right thoracic and right abdominal air sacs were thickened and opaque and contained three or four tightly coiled nematodes of the genus Serratospiculum. A fibrinous deposit surrounded each nematode. The nematodes were tightly ad

Epizootic of Coccidiosis in Free-Flying Lesser Scaup

A coccidiosis epizootic has occurred in lesser scaup (Aythya affinis) at Bluestem Reservoir in eastern Nebraska during the spring in each of three recent years: 1976-1978. Losses peaked during the period from mid-March through April. As much as 29% of the peak population of scaup using the reservoir died. Necropsies of 72 of the nearly 1390 scaup that died revealed destruction and sloughing of the intestinal mucosa and associated hemorrhaging. Fibrinonecrotic cores were frequently found in the intestinal lumens. Scrapings from the intestinal mucosal contained massive numbers of oocysts of the coccidian Eimeria aythyae. This is the first report of recurrent epizootics of coccidiosis in freeflying waterfowl.

Isolation of Streptococcus zooepidemicus from a Bald Eagle (Haliaeetus leucocephalus)

From 1960 to 1974, 307 bald eagles found dead at various locations in the United States were submitted to the U.S. Fish and Wildlife Services Patuxent Wildlife Research Center (PWRC), Laurel, Maryland, for necropsy and subsequent chemical analysis for organochlorine pesticide residues. This note reports the isolation of Streptococcus zooepidemicus from the intestine of one of these eagles and is the first record of isolation of this organism from the American bald eagle.