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Matthew C. Perry

Publications and source records attributed to Matthew C. Perry.

At least 73 records · Page 4Linked to original sources
USGS1989

Behaviour of captive canvasbacks Aythya valisineria fed different diets during winter

Time activity budget studies were conducted on captive Canvasbacks manintained on ad libitum diets with varying levels of protein and energy during the winter of 1978-79 and 1979-80. No differences could be detected in the behaviour of the ducks as a result of the diets they received. Differences due to season and sex were observed for some behaviours. Activity decreased (P<0.05) during the winter apparently as a mechanism to conserve energy. This decrease occurred in mid-winter irrespective of diet quality and appeared to be an endogenous component of the Canvasbacks' annual cycle. This behaviour pattern has been observed in the wild and seems to persist in captive Canvasbacks.

Wildfowl↗
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↗
USGS1988

Sex specificity of behavioral dominance and fasting endurance in wintering canvasbacks: Experimental results

Hand-reared canvasbacks (Aythya valisineria) of varying sex ratios were maintained in pens during winter 1980-81 (3M-3F, 6M-0F, 0M-6F) and winter 1981-82 (4M-2F, 2M-4F) and fed two diets (control and stress). They were observed during feeding trials to determine intrasexual and intersexual aggressive activity. There was little evidence that either diet or sex ratio affected the total number of aggressive encounters. Females fed both control and stress diets were more aggressive and spent more time in the small feeding areas than males in pens with 3M-3F, 4M-2F, and 2M-4F sex ratios. Stressed ducks tended to weigh less than controls throughout the study. Females in the 3M-3F and 4M-2F pens weighed less than those in the 0M-6F and 2M-4F pens, respectively. However, relative weight changes throughout the winter were similar for males and females. Thus, results of these experiments do not lead to conclusive rejection of either the behavioral dominance hypothesis or the fasting endurance hypothesis.

Book chapter↗
USGS1986

Influence of nutrients on feed intake and condition of captive canvasbacks in winter

Dramatic changes in the food habits and distribution of canvasbacks ( Aythya valisineria ) in Chesapeake Bay during the 1970's generated a need to evaluate the nutritional value of food items and the requirements of this species on its wintering grounds. Groups of captive canvasbacks were maintained ad libitum on 5 diets during the winters of 1978-79 and 1979-80 to evaluate the effects of varying protein and energy levels on feed intake and condition. Feed intake during the 1979-80 winter was 42% greater for those ducks fed the low energy (1,543 kcal/kg) diet than for those fed the high energy (3,638 kcal/kg) diet. Canvasbacks fed the high energy diet, however, consumed 317 kcal/bird day, whereas those fed the low energy diet consumed only 191 kcal/bird day. Body weight of males and females did not differ among groups fed different diets, but there were seasonal differences (P < 0.05) for both sexes aggregated across diets. Data from this study indicate that canvasbacks may be unable to adjust intake rates to compensate for low energy foods and subsequently may store less fat or modify behavior. However, decreased weight, feed intake, and activity of ducks fed ad libitum rations occurred in mid-winter irrespective of diet quality and appeared to be an endogenous component of their annual cycle that persists in captivity. These changes apparently have a selective advantage of increasing the probability of survival in ducks by decreasing energy expenditure during periods of winter stress.

Maryland, Virginia↗
USGS1986

Blood chemistry and hematocrit of captive and wild canvasbacks

Blood chemistry and packed cell volume (PCV) did not vary among groups of captive canvasbacks ( Aythya valisineria ) maintained ad libitum on 5 diets varying in metabolizable energy (ME) and protein. Ducks fed low quality diets increased their consumption so that all ducks were obtaining similar amounts of energy and protein. Some variables, including cholesterol, were found to differ between the sexes and ages of captive ducks. Seasonal differences were detected in the blood chemistry of captive canvasbacks. Four of the 5 enzyme values increased from October to January and then declined to April. PCV increased from 45 in October to 51 in April. Overall, blood chemistry values and PCV's were highly variable and did not appear to be good discriminators for age, sex, and diet of captive canvasbacks. Differences detected between captive and wild canvasbacks were attributed to increased stress of wild ducks during handling.

Journal of Wildlife Management↗
USGS1986

Seasonal influence of nutrients on the physiology and behavior of captive canvasbacks (Aythya valisineria)

Captive canvasbacks (Aythya valisineria) were maintained ad libitum on five diets during the winters of 1978-79 and 1979-80 to evaluate the effects of varying protein and energy levels on feed intake and condition. Diets were formulated to simulate either a natural diet high in invertebrates or one high in vegetation. Two diets low in protein and energy simulated stress diets. Feed intake during the 1979-80 winter, when diets varied the most, was 30% higher for canvasbacks fed the low energy (1543 kcal/kg) diet than for canvasbacks fed the high energy (3638 kcal/kg) diet. Body weight of males and females did not differ between groups fed different diets, but there were seasonal differences (P < 0.05) for both sexes aggregated across diets. Feed intake and body weights were greatest in November and April and least in January and February. Convasbacks lost weight and ate less during the most stressful periods despite ad libitum feed supplies. No differences could be detected in the behavior of captive canvasbacks as a result of the diets they received. Differences due to season and sex were observed for some behaviors. Inactivity increased (P < 0.05) during the winter apparently as a mechanism to conserve energy.Overall, captive canvasbacks were able to maintain themselves during winter on diets with as little as 10% protein and 1543 kcal/kg provided adequate quantities of food were available. Availability of low energy food (e.g. clams) may be the limiting factor in regard to winter survival of wild canvasbacks. The distribution and abundance of canvasbacks in some wintering areas ultimately has been influenced by the quantity and probably the quality of available nutrients.Data from this study indicate that canvasbacks are unable to adjust intake rates to compensate for low energy foods and may subsequently store less fat or modify behavior and microclimate. However, decreased weight, feed intake, and activity of ducks fed ad libitum rations occurred in mid-winter irrespective of diet quality and appeared to be an endogenous component of their annual cycle which persists in captivity. These changes apparently have a selective advantage of increasing the probability of survival in ducks by decreasing energy expenditure during periods of winter stress.

Dissertation Abstracts International↗
USGS1985

Seasonal Influence of Nutrients on the Physiology and Behavior of Captive Canvasbacks (Aythya valisineria)

Captive canvasbacks (Aythya valisineria) were maintained ad libitum on five diets during the winters of 1978-79 and 1979-80 to evaluate the effects of varying protein and energy levels on feed intake and condition. Diets were formulated to simulate either a natural diet high in invertebrates or one high in vegetation. Two diets low in protein and energy simulated stress diets. Feed intake during the 1979-80 winter, when diets varied the most, was 30% higher for canvasbacks fed the low energy (1543 kcal/kg) diet than for canvasbacks fed the high energy (3638 kcal/kg) diet. Body weight of males and females did not differ between groups fed different diets, but there were seasonal differences (P(O.05) for both sexes aggregated across diets. Feed intake and body weights were greatest in November and April and least in January and February. Canvasbacks lost weight and ate less during the most stressful periods despite ad libitum feed supplies. No differences could be detected in the behavior of captive canvasbacks as a result of the diets they received. Differences due to season and sex were observed for some behaviors. Inactivity increased (P(0.05) during the winter apparently as a mechanism to conserve energy. Overall, captive canvasbacks were able to maintain themselves during winter on diets with as little as 10% protein and 1543 kcal/kg provided adequate quantities of food were available. Availability of low energy food (e.g. clams) may be the limiting factor in regard to winter survival of wild canvasbacks. The distribution and abundance of canvasbacks in some wintering areas ultimately has been influenced by the quantity and probably the quality of available nutrients. Data from this study indicate that canvasbacks are unable to adjust intake rates to compensate for low energy foods and may subsequently store less fat or modify behavior and microclimate. However, decreased weight, feed intake, and activity of ducks fed ad libitum rations occurred in mid-winter irrespective of diet quality and appeared to be an endogenous component of their annual cycle which persists in captivity. These changes apparently have a selective advantage of increasing the probability of survival in ducks by decreasing energy expenditure during periods of winter stress.

Book↗
USGS1984

The Patuxent team

Explore the source record for details and available documents.

Book chapter↗