Canada Goose Goslings Research Articles

Ecological implications of reduced forage quality on growth and survival of sympatric geese.

Allometric constraints associated with digesting leaves require relatively small avian herbivores to consume high-quality forage. How such constraints are overcome during ontogeny when energy and nutrient requirements are relatively high has not been adequately explored. We compared growth trajectories of Canada and lesser snow goose goslings raised on grass-based diets that differed in protein (10%, 14% or 18%) and fibre (30% or 45%) with those of free-living goslings on Akimiski Island, Canada. This common-garden experiment allowed us to test the hypotheses that (i) smaller-bodied geese are more negatively affected by reduced forage quality than larger-bodied geese, and (ii) goslings from subarctic brood-rearing areas have a limited capacity to slow growth in response to reduced forage quality. Canada goose goslings fed low-protein (10%) diets were on average 44% lighter in body mass, had slower growth rates and were delayed >20days in reaching 90% of asymptotic size compared with Canada goose goslings fed 18% protein. In contrast, snow goose goslings were unable to survive on the low-protein diets, and those fed high- or medium-protein diets grew at a similar rate and achieved similar asymptotic size. Canada and snow goose goslings fed low-protein diets had reduced growth rates of the tarsus and delayed emergence of the 9th primary. Free-ranging Canada goslings on Akimiski Island were similar in mass and structural size to captive-reared goslings fed low-protein diets. In contrast, snow goslings were similar in mass and structural size to the captive-reared goslings fed the high- and medium-protein diets. This suggests that degraded habitats with mostly low-protein forage may be able to support Canada goslings better than snow goslings which require higher-quality forage to survive. Size-related differences in gosling growth and survival in response to diminished diet quality may influence population size when available food reaches a lower threshold in protein content. However, goslings can avoid such density-dependent population regulation if they are able to move their broods and find adequate quality and quantity of forage.

Golden Eagles (<em>Aquila chrysaetos</em>) breeding in Wapusk National Park, Manitoba

The North American subspecies of the Golden Eagle (Aquila chrysaetos) is of conservation concern throughout Canada. The species is not currently known to breed in Manitoba. In 2011 and 2012, during the course of surveys in Wapusk National Park of Canada in northeastern Manitoba, seven pairs of Golden Eagles and one sub-adult were observed. The identification of nests in proximity to three pairs, the presence of an adult at one nest, and visible white down feathers on two nests confirm breeding and extend the breeding range of the Golden Eagle into Manitoba, where breeding was previously uncertain. The three occupied nests were 14 km (n = 2) and 31 km (n = 1) from the nearest adjacent occupied nest identified. Foraging on Canada Goose (Branta canadensis) goslings was observed. Further research is needed to determine the overall nest density and the diet of Golden Eagles in northeastern Manitoba.

Predators of Dusky Canada Goose goslings and the effect of transmitters on gosling survival

The population of Dusky Canada Geese {Branta canadensis occidentalis) has been in long-term decline, likely due to reduced breeding productivity. To identify causes of mortality, we monitored goslings marked with radio transmitters on the western Copper River Delta, Alaska, from 1997 to 1999. Almost all gosling mortality (96%; 81 of 84) was due to pr?dation, with mink (Mustela vison) and Bald Eagles (Haliaeetus leucocephalus) the most important predators. Bald Eagles are also major nest predators and, thus, appear to play a key role in limiting the breeding productivity of Dusky Canada Geese. Daily survival rate for goslings to 28 d of age was lower (0.011; 95% CI 0.002?0.024) for those with transmitters than for those without, but did not differ for older goslings (29?45 d). Although finer resolution in the timing of the transmitter effect within the first 28 d was not possible, we found that, by limiting our sample to goslings that survived until after 2?3 d posthatching, support for a transmitter effect was much reduced. Younger, smaller birds are inherently more vulnerable than older birds to transmitter effects. In addition, the process of radio-marking may have delayed the departure of goslings from nests and increased their risk of mortality shortly after hatching. Although radio transmitters may often be the only practical means for determining causes of mortality for young waterfowl, we suggest caution in using transmitters because of their potential negative effects, particularly during the first few days after hatching.

Survival of Dusky Canada Goose Goslings in Relation to Weather and Annual Nest Success

The dusky Canada goose (Branta canadensis occidentalis) population has been in long-term decline, likely due to reduced breeding productivity, but gosling survival of this population had not been examined. We studied gosling survival in broods of radiomarked adult females on the western Copper River Delta, Alaska, USA, during 1997–1999 and 2001–2003. Survival estimates for dusky Canada goose goslings to 45 days (x = 0.32) were below estimates from most previous studies of geese. Daily survival of goslings increased with age and decreased with date of hatch. Precipitation during the first 3 days post-hatch was negatively related to gosling survival and this effect increased with date. Annual estimates of gosling survival were positively correlated with annual estimates of nest success, suggesting overlap in factors affecting nest and gosling survival. Nest success probably also directly affected gosling survival, because survival decreased with hatch date and more broods hatched from renests during years with low nest success. Gosling survival appears to play an important role in limiting current productivity of this population. Management directed at increasing nest success would likely also improve gosling survival. We recommend additional research directed at examining sources of gosling mortality and the link between nest success and gosling survival.

Field evaluation of an avian risk assessment model

We conducted two laboratory subacute dietary toxicity tests and one outdoor subacute dietary toxicity test to determine the effectiveness of the U.S. Environmental Protection Agency's deterministic risk assessment model for evaluating the potential of adverse effects to birds in the field. We tested technical-grade diazinon and its D.Z.N 50W (50% diazinon active ingredient wettable powder) formulation on Canada goose (Branta canadensis) goslings. Brain acetylcholinesterase activity was measured, and the feathers and skin, feet, and gastrointestinal contents were analyzed for diazinon residues. The dose-response curves showed that diazinon was significantly more toxic to goslings in the outdoor test than in the laboratory tests. The deterministic risk assessment method identified the potential for risk to birds in general, but the factors associated with extrapolating from the laboratory to the field, and from the laboratory test species to other species, resulted in the underestimation of risk to the goslings. The present study indicates that laboratory-based risk quotients should be interpreted with caution.

Decomposed gosling feet provide evidence of insecticide exposure.

Canada goose goslings were exposed to turf sprayed with DZN diazinon 50W application (2.24 kg a.i./ha). The control plot was subjected to a water application. One foot from each bird was placed outdoors for 7 d to decompose and the other foot was kept frozen. Diazinon residues were analyzed on both feet. Results showed that diazinon was detected from undecomposed and decomposed feet of the birds. Diazinon residues were below the level of detection (<0.01 ppm, a.i.) on the feet from the control goslings. Decomposed feet may be used for determining insecticide exposure when the traditional matrices are not available.

Influence of Body Size and Condition on Harvest and Survival of Juvenile Canada Geese

Direct recoveries for Canada goose (Branta canadensis interior) goslings from the portion of the Southern James Bay Population (SJBP) on Akimiski Island, Nunavut, Canada, have declined markedly since 1987. We suspected that poor gosling nutrition, due to limited food resources on brood-rearing areas, was causing low survival. Consequently, we measured body size and condition of 2,893 unfledged goslings during late July and early August, 1994-1996. Based on 128 recoveries of dead birds during hunting seasons and 69 recaptures during summer on Akimiski Island, we estimated the separate influences of gosling size and condition on subsequent probabilities of recovery by hunters and survival. Estimated survival probabilities were 0.025, 0.051, and 0.147, and reporting probabilities were 0.0026, 0.0051, and 0.0142 for 1994-1996, respectively. Annual variation in both probabilities was related to size and condition of goslings, which were largest and in the best condition in 1996, followed by 1995, and then 1994. Estimates of slopes suggested that relatively small increases in both body size and condition resulted in increased survival and reporting probabilities. Unlike previous waterfowl research, our results showed that the largest goslings, and those in the best condition, were the most likely to be shot. We suggest that goslings in poor condition died on Akimiski Island before they fledged. We conclude that food availability was limiting recruitment, and predict that harvest restrictions on SJBP Canada geese will not result in an increase in the segment of the population that nests on Akimiski Island.

Growth and Development of Prefledging Canada Geese and Lesser Snow Geese: Ecological Adaptation or Physiological Constraint?

AbstractNeonate, gosling, and adult Canada Geese (Branta canadensis interior) and Lesser Snow Geese (Chen caerulescens caerulescens) were collected to evaluate if growth rates and developmental patterns differed interspecifically and to determine if such differences were better explained by physiology of the growth process or by ecological conditions historically experienced by those two species. Patterns of growth and development of Canada and Lesser Snow goose goslings were similar to those reported for other Arctic geese, but differences in relative growth rates and developmental patterns of external structures, digestive organs, and skeletal muscles were observed between these two species. As compared to Canada Geese, body parts associated with locomotion and acquisition or processing of food generally increased at relatively faster rates and were more developed relative to adult size in Lesser Snow Geese. Relative rates of increase for carcass protein and body mass in these two species did not support a physiological constraint on growth. Rates and patterns of growth and development were better explained as adaptations to ecological factors, such as growing season and nesting or brood rearing conditions, historically experienced by these two species.

GROWTH AND DEVELOPMENT OF PREFLEDGING CANADA GEESE AND LESSER SNOW GEESE: ECOLOGICAL ADAPTATION OR PHYSIOLOGICAL CONSTRAINT?

Abstract Neonate, gosling, and adult Canada Geese (Branta canadensis interior) and Lesser Snow Geese (Chen caerulescens caerulescens) were collected to evaluate if growth rates and developmental patterns differed interspecifically and to determine if such differences were better explained by physiology of the growth process or by ecological conditions historically experienced by those two species. Patterns of growth and development of Canada and Lesser Snow goose goslings were similar to those reported for other Arctic geese, but differences in relative growth rates and developmental patterns of external structures, digestive organs, and skeletal muscles were observed between these two species. As compared to Canada Geese, body parts associated with locomotion and acquisition or processing of food generally increased at relatively faster rates and were more developed relative to adult size in Lesser Snow Geese. Relative rates of increase for carcass protein and body mass in these two species did not suppo...

Composition of Eggs and Neonates of Canada Geese and Lesser Snow Geese

AbstractWe collected eggs, neonates, and adults of Canada Geese (Branta canadensis interior) and Lesser Snow Geese (Chen caerulescens caerulescens) from Akimiski Island, Nunavut, during the 1996 breeding season. This was done to assess interspecific differences in egg composition, egg-nutrient catabolism, developmental maturity, tissue maturity, and body reserves, and to relate observed differences in those variables to ecological conditions historically experienced by Canada Geese and Lesser Snow Geese. Eggs of both species had identical proportional compositions, but Canada Goose embryos catabolized 13% more of their egg protein, whereas Lesser Snow Goose embryos catabolized 9% more of their egg lipid. Neonate Canada Geese and Lesser Snow Geese had similar protein reserves, relative to body size, but Lesser Snow Geese had relatively smaller lipid reserves than did Canada Geese. Relative to conspecific adults, Lesser Snow Goose goslings generally were structurally larger at hatch than were Canada Goose goslings. Neonate Lesser Snow Geese had more developmentally mature keels, wings, and breast muscles, and larger gizzards and caeca for their body size, than did neonate Canada Geese. Despite hatching from smaller eggs and having a shorter period of embryonic growth, skeletal muscles and gizzard tissues of Lesser Snow Geese were more functionally mature than those of Canada Geese. Increased lipid use during embryonic development could account for how Lesser Snow Geese hatched in a more developmentally and functionally mature state. In turn, differences in developmental and functional maturity of Lesser Snow Geese, as compared to Canada Geese, likely are adaptations that offset metabolic costs associated with their small body size, or to selection pressures associated with high arctic environmental conditions and colonial nesting and brood rearing.

COMPOSITION OF EGGS AND NEONATES OF CANADA GEESE AND LESSER SNOW GEESE

We collected eggs, neonates, and adults of Canada Geese (Branta canadensis interior) and Lesser Snow Geese (Chen caerulescens caerulescens) from Akimiski Island, Nunavut, during the 1996 breeding season. This was done to assess interspecific differences in egg composition, egg-nutrient catabolism, developmental maturity, tissue maturity, and body reserves, and to relate observed differences in those variables to ecological conditions historically experienced by Canada Geese and Lesser Snow Geese. Eggs of both species had identical proportional compositions, but Canada Goose embryos catabolized 13% more of their egg protein, whereas Lesser Snow Goose embryos catabolized 9% more of their egg lipid. Neonate Canada Geese and Lesser Snow Geese had similar protein reserves, relative to body size, but Lesser Snow Geese had relatively smaller lipid reserves than did Canada Geese. Relative to conspecific adults, Lesser Snow Goose goslings generally were structurally larger at hatch than were Canada Goose goslings. Neonate Lesser Snow Geese had more developmentally mature keels, wings, and breast muscles, and larger gizzards and caeca for their body size, than did neonate Canada Geese. Despite hatching from smaller eggs and having a shorter period of embryonic growth, skeletal muscles and gizzard tissues of Lesser Snow Geese were more functionally mature than those of Canada Geese. Increased lipid use during embryonic development could account for how Lesser Snow Geese hatched in a more developmentally and functionally mature state. In turn, differences in developmental and functional maturity of Lesser Snow Geese, as compared to Canada Geese, likely are adaptations that offset metabolic costs associated with their small body size, or to selection pressures associated with high arctic environmental conditions and colonial nesting and brood rearing.

Field evaluation of lead effects on Canada geese and mallards in the Coeur d'Alene River Basin, Idaho.

Hatch year (HY) mallards (Anas platyrhynchos) in the Coeur d'Alene (CDA) River Basin had higher concentrations of lead in their blood than HY Western Canada geese (Branta canadensis moffitti) (geometric means 0.98 versus 0.28 microg/g, wet weight). The pattern for adults of both species was similar, although geometric means (1.77 versus 0. 41 microg/g) were higher than in HY birds. HY mallards captured in the CDA River Basin in 1987 contained significantly lower lead concentrations in their blood than in 1994-95 (0.36 versus 0.98 microg/g); however, some very young mallards were sampled in 1987, and concentrations in adults were not significantly different in 1987, 1994, or 1995 (1.52, 2.07, 1.55 microg/g, respectively). Both species in the CDA River Basin in 1994-95 showed significantly reduced red blood cell delta-aminolevulinic acid dehydratase (ALAD) activity compared to the reference areas: Canada geese (HY -65.4 to -86.0%, adults -82.3%), and mallards (HY -90.7 to -95.5%, adults -94. 1%). Canada goose goslings were divided into size classes, and the two smaller classes from the CDA River Basin had significantly elevated free erythrocyte protoporphyrin (protoporphyrin) levels compared to the reference area (15.2x and 6.9x). HY and adult mallards both had significantly elevated protoporphyrin (5.9x and 7. 5x). Recognizing that interspecific differences exist in response and sensitivity to lead, it appears (at least for hemoglobin and hematocrit) that Canada geese were more sensitive to lead than mallards, i.e., adverse hematologic effects occur at lower blood lead concentrations. Only Canada geese from the CDA River Basin, in spite of lower blood lead concentrations, had significantly reduced mean hemoglobin and hematocrit values. No euthanized Canada geese (all HYs) from CDA River Basin were classified as clinically lead poisoned, but 38 Canada geese found dead in the CDA River Basin during a concurrent study succumbed to lead poisoning between 1992 and 1997. Only 6 (15.8%) of these 38 contained ingested lead shot, which contrasts greatly with the 75-94% incidence of ingested lead shot when mortality was due to lead shot ingestion. Lead from other contaminated sources (i.e., sediments and vegetation) in the CDA River Basin was strongly implicated in most Canada goose deaths. Based on the 31 live mallards and Canada geese collected in the CDA River Basin, which were representative of the live populations blood sampled only, the prevalence of subclinical and clinical lead poisoning (as determined by liver lead concentrations, excluding birds with ingested lead shot) was higher in mallards: subclinical (4 of 8, 50% HYs and 6 of 11, 55% adults); clinical (0% HYs and 4 of 11, 36% adults), with less data available for Canada geese (only 1 of 9, 11% HYs marginally subclinical). The clinically lead-poisoned mallards had extremely high concentrations of lead in blood (2.69-8. 82 microg/g) and liver (6.39-17.89 microg/g). Eight mallards found dead in the CDA River Basin during a concurrent study were diagnosed as lead poisoned, and only one (12.5%) contained ingested lead shot, which again strongly implicates other lead sources. The finding of dead lead poisoned Canada geese together with the high percentage of live mallards classified as subclinically or clinically lead poisoned, in combination with the low incidence of ingested lead shot causes us concern for both of these species, which live in association with lead-contaminated sediment in the CDA River Basin.

Effects of Saline Environments on the Survival of Wild Goslings (Branta canadensis)

Research on ducklings and goslings has demonstrated that young birds hatched in moderate to high saline environments without access to fresh drinking water grow and develop slower, and have increased mortality rates. Most direct saline-induced mortality happens before day 6 of life, after which time the nasal salt glands become functional. At Fish Springs National Wildlife Refuge in western Utah, the water available to Canada goose (Branta canadensis) goslings ranged from brackish to highly saline (3100–25,000 µS/cm) throughout the summer and differed spatially across the impoundments; no fresh water was available. We followed collar-marked, radio-marked and unmarked broods from hatching to day 15 to determine early survival of all goslings hatched in 1997. Nineteen broods hatched between 25 April and 25 May. We analyzed the relationship between specific conductivity of water and gosling mortality in 1997. The levels of salinity found at the refuge within 15 d after hatching were independent of mortality. During dry years salinity levels increase earlier in the Spring and may limit gosling productivity.

Relationships among egg size, energy reserves, growth rate, and fasting resistance of Canada Goose goslings from southern Ontario

Eggs of wild giant Canada Geese (Branta canadensis maxima) breeding in southern Ontario were collected and incubated artificially. Components of the total nutrient reserve of goslings were measured at hatch to test whether relationships existed between egg size, gosling weight, and weight of reserves in goslings. The growth rate of fed goslings of different weights at hatch was measured for 25 days. The nutrient reserves remaining in goslings of different hatch weights were measured after 2, 4, and 6 days of starvation. Egg size and gosling weight were not highly correlated in this population (r = 0.63). Larger goslings generally contained more reserves than small goslings (P &lt; 0.05), but much variability occurred in this relationship. Gain in weight over 25 days was not related to the weight at hatch. Starved goslings with higher body fat levels had significantly higher dry carcass weights than goslings with low body fat levels (P &lt; 0.01), suggesting a sparing action of fat on body tissues. The apparent survival of small goslings and goslings with small reserves, combined with the great variability in egg size, gosling weight, and extent of metabolic reserves, suggests relaxed selection in the southern Ontario environment where this population breeds.

Foraging behavior of cackling Canada Goose goslings: implications for the roles of food availability and processing rate.

Time spent foraging (and in other activities), rate of pecking at food items and length of foraging and nonforaging periods were studied in cackling Canada goose (Branta canadensis minima) goslings during brood-rearing on the Yukon-Kuskokwim Delta, Alaska in 1978 and 1979. Brood density on the study area was twice as high in 1978 (23 broods) as in 1979 (12 broods) owing in part to annual variation in nesting density and success. Peck-rates were lower in meadows during 1978 than in 1979. There was no between-year difference in time spent foraging prior to the adult molt (59% of daylight hours) but during molt, goslings spent more time feeding in 1978 (70%) than in 1979 (56%). Prior to the adult molt, 12.2 and 11.9 hours were spent feeding each day in 1978 and 1979 respectively, whereas goslings fed for 13.4 and 10.6 hours daily, in the two years during molting and fledging. Increased foraging time during the molt in 1978 completely compensated for lower peck rates so that total number of pecks per day during this period were similar in 1978 (62,800 pecks/d) and 1979 (57,900 pecks/d). Elsewhere, we reported that cackling geese significantly reduced the availability of their preferred food in 1979 and this food comprised a smaller proportion of the diet in 1978 than 1979. This variation in diet suggests that preferred foods were less available at higher brood densities, resulting in annual variation in foraging behavior. Lengths of foraging periods increased during brood-rearing in both years but were longer on average in 1978. There was no seasonal or between year variation in the length of nonforaging periods. The alternating pattern of foraging and nonforaging periods suggests that rate of processing limits rate of food intake because a relatively constant period of time was regularly required to empty the esophagus before foraging could be resumed. The restriction of food intake by digestive processes increased the importance of dietary nutrient concentrations because low nutrient concentrations could not be compensated for by higher rates of food intake.

Experimental duck plague in blue-winged teal and Canada geese.

Ten adult blue-winged teal (Anas discors) and six Canada goose (Branta canadensis) goslings were inoculated with liver tissue from a natural case of duck plague in a wild mallard (Anas platyrhynchos). Four additional teal were placed in contact with the inoculated ducks. Inoculated teal died 63.5-68 hr after inoculation; two of the contact teal died 161-162 hr after exposure. Three of the goslings died 119-133 hr after inoculation, the others were killed when moribund 90-133 hr postinfection. The clinical course of disease was extremely rapid in both species. Signs were limited to sudden onset of profound weakness, ataxia, tremors and terminal convulsions. The only consistent gross lesion in the teal was a small dark spleen; half the teal also had inconspicuous foci of epithelial necrosis in the distal esophagus and in the cloaca. Goslings had more severe lesions, with focal hepatic necrosis visible in all, and mucosal necrosis over the intestinal lymphoid tissue, and intestinal hemorrhage in three birds each. Microscopic lesions in both species were similar to those reported in mallards. Duck plague might be overlooked at necropsy of blue-winged teal, because of the paucity of gross lesions.

Relationships between Sex of Gosling and Position in the Laying Sequence, Egg Mass, Hatchling Size, and Fledgling Size

The sex of Canada Goose (Branta canadensis) goslings was not correlated with the position in the laying sequence, egg mass, or size of goslings at hatching. However, male goslings were larger at fledging than female goslings. This suggests that sex determination in Canada Geese and probably in other Anserinae occurs randomly over the laying sequence and that parental allocation of resources is equal for male and female goslings. Received 19 February 1986, accepted 25 August 1986. SEX of offspring may be of unequal value to the fitness of parents if the sex ratio of the breeding population varies or if the costs of producing each sex differs (Maynard Smith 1984). If parents provide more care to one sex or if the female can control the sex ratio of her progeny to increase survival of one sex, paren- tal fitness will increase also. The possibility that a female bird can control the sex of her off- spring has been suggested (Ankney 1982, Ry- der 1983, Weatherhead 1985). Theoretically, this would be adaptive under specific circum- stances (Trivers and Willard 1973, Myers 1978). The sex ratio of offspring varies through the breeding season in Red-winged Blackbirds (Agelaius phoeniceus; Fiala 1981, Blank and No- lan 1983) and Common Grackles (Quiscalus quis- cula; Howe 1977), and varies with position in the laying sequence in Snow Geese (Chen caeru- lescens; Ankney 1982; but see Cooke and Harm- sen 1983), Ring-billed Gulls (Larus delawarensis; Ryder 1983), and Red-winged Blackbirds (Fiala 1981, Weatherhead 1985). I report on the relationships between the sex of Canada Goose (Branta canadensis) goslings and four variables: position in the laying sequence, egg mass, hatchling size, and fledgling size. The purpose was to determine whether females controlled the sex of their offspring in relation to the position in the laying sequence and to examine if parental allocation of resources, as determined by egg mass, hatchling size, and fledgling size, was equal in the two sexes. STUDY AREA AND METHODS

Growth and Development of Canada Goose Goslings

Growth and Development of Canada Goose Goslings

The Feeding of Some Ornithophilic Black Flies (Diptera: Simuliidae) in the Laboratory and Their Role in the Transmission of Leucocytozoon simondi2

Techniques and equipment are described for feeding, in the laboratory, Cnephia invenusta (Walker), Simulium innocens Shewell, and S. rugglesi Nicholson & Mickel collected from exposed birds at the Seney National Wildlife Refuge, Seney, Michigan, and C. ornithophilia Davies, Peterson, & Wood, S. euryadminiculum Davies, and S. rugglesi reared from larvae at the Seney Refuge ( S. rugglesi ) and the Patuxent Wildlife Research Center, Laurel, Maryland. In 4 feeding experiments with C. invenusta on Pekin ducklings, 109 fed of 194 flies exposed; in 2 experiments with S. innocens on a mallard duckling and an Emden gosling, 35 fed of 65 flies exposed; in 12 experiments with S. rugglesi on mallard ducklings and Canada goose goslings, 465 fed of 1215 flies exposed; in 40 experiments with C. ornithophilia on Khaki Campbell, mallard, and Pekin ducklings and yearling Canada and Emden goslings, 950 fed of 1713 flies exposed; and, in 2 experiments with S. euryadminiculum on Pekin ducklings, 27 fed of 46 flies exposed. Feeding time varied from 2.10 to 15 minutes. C. ornithophilia, S. innocens , and S. rugglesi fed on Khaki Campbell, mallard, and Pekin ducklings and yearling Canada geese infected with Leucocytozoon simondi Mathis & Leger were held 4-7 days after the blood meal. The flies were triturated in physiological saline and deactivated calf serum and inoculated intravenously and intraperitoneally in parasite-free Pekin, Khaki Campbell, and mallard ducklings and Canada goose goslings. Birds became infected with L. simondi 9-14 days after being inoculated with C. ornithophilia ; 4-7 days after being inoculated with S. innocens ; and 9 days after being inoculated with S. rugglesi . Starved, laboratory-fed C. ornithophilia fed first on L. simondi infected Khaki Campbell and Pekin ducklings, held 4-7 days at room temperature, then fed for the 2nd time on parasite-free Pekin ducklings, transmitted the infection by their bite. The birds showed young parasites in the peripheral blood 10 and 11 days following the 2nd feeding.

Goose virus hepatitis in the Canada Goose and Snow Goose.

Seven Canada Goose goslings and one Snow Goose gosling died suddenly and were presented for diagnosis. Gross and microscopic lesions of hepatitis were observed in all birds. A virus was isolated in embryonated goose eggs which, on the basis of complement fixation and immunofluorescence tests, was identified as goose hepatitis virus. The epornitiology of this virus is discussed.