Parental Care and Feeding Ecology of Golden Eagle Nestlings

The Auk ◽  
1984 ◽  
Vol 101 (4) ◽  
pp. 753-760 ◽  
Author(s):  
Michael W. Collopy
Keyword(s):  
Parental Care ◽  
Food Consumption ◽  
Prey Availability ◽  
Birds Of Prey ◽  
Brood Rearing ◽  
Daily Food ◽  
Golden Eagles ◽  
Consumption Rates ◽  
The Mean ◽  
Capture Rates

AbstractA field study of Golden Eagles (Aquila chrysaetos) nesting in and near the Snake River Birds of Prey Area was conducted during 1977-1979. Patterns of parental care differed between female and male eagles during incubation and chick rearing; males consistently captured more food throughout all phases of brood rearing (1.2 vs. 0.6 prey/day), while females typically fed and tended the offspring. During the 7th through 9th week of chick rearing, when the food requirements of nestlings were greatest, the female contributed 43% of the prey biomass. No differences were observed in mean daily capture rates between 1978 and 1979 or between parents of one-chick broods and parents of two-chick broods. Although there were no differences between the sexes in the mean weight of prey captured, there were significant differences among pairs, suggesting differences in prey availability or hunting ability. The daily food consumption of eaglets increased as chick rearing progressed and peaked between the 7th and 9th week. Comparisons between eaglets in different-sized broods revealed that individuals in multiple-chick broods received more food from adults than those in one-chick broods. Late in chick rearing, however, those chicks competing with siblings for food had lower consumption rates.

Water Turnover and Estimated Food-Consumption in 3 Species of Fairy-Wren (Malurus Spp)

1989 ◽  
Vol 16 (2) ◽  
pp. 187 ◽  
Author(s):  
SC Tidemann ◽  
B Green ◽  
K Newgrain
Keyword(s):  
Drinking Water ◽  
Food Consumption ◽  
Climatic Conditions ◽  
Water Turnover ◽  
Interspecific Differences ◽  
Water Influx ◽  
Daily Food ◽  
Consumption Rates ◽  
Dry Conditions ◽  
Malurus Cyaneus

Water influx rates and estimated food consumption rates were determined for adults, juveniles and nestlings of three co-existing species of fairy-wrens: superb (Malurus cyaneus), variegated (M. lamberti) and white-winged (M. leucopterus). There were no significant interspecific differences with respect to water influxes of either juveniles or adults, but variation within species was large. Adults and juveniles had higher water influx values and daily food requirements than nestlings. M. cyaneus nestlings had higher mass-specific water influxes and food intakes than both M. leucopterus and M, lamberti, but the latter two did not differ in these parameters. The higher mortality of M. cyaneus and the requirement for drinking water during hot, dry conditions indicate that the inland distribution and abundance of this species are more constrained by climatic conditions than are populations of M. lamberti and M. leucopterus.

An in situ Evaluation of the Day-to-Day Variation in the Quantity of Food Consumed by Fish

1993 ◽  
Vol 50 (10) ◽  
pp. 2157-2165 ◽  
Author(s):  
Marc Trudel ◽  
Daniel Boisclair
Keyword(s):  
Time Series ◽  
Water Temperature ◽  
Food Consumption ◽  
Daily Ration ◽  
Consumption Rates ◽  
Sampling Intervals ◽  
The Mean ◽  
Food Consumed

We tested the hypothesis that the mean quantity food consumed by fish in situ does not vary significantly over successive days. The daily ration of minnows (Phoxinus eos × P. neogaeus) was estimated over 5–12 consecutive days (June 1–5, July 6–17, and August 3–9, 1992). Mean daily ration ranged from 0.60 to 1.32 g dry∙100 g wet−1∙d−1 and varied significantly over consecutive days in June and July, but not in August. Average day-to-day variation in food consumption rates ranged from 7.0 to 16.3%. Mean daily ration was not influenced by either water temperature or percent cloudiness. Simulated long-term consumption rates of minnows did not vary by more than 19.3% among sampling intervals ranging from 1 to 30 d. We conclude that long-term consumption rates can be accurately determined using time series of daily ration estimated at 3- to 4-wk intervals.

Metabolic Allometry of Larval and Juvenile Yellow Perch (Perca flavescens): In Situ Estimates and Bioenergetic Models

1990 ◽  
Vol 47 (3) ◽  
pp. 554-560 ◽  
Author(s):  
John R. Post
Keyword(s):  
Food Consumption ◽  
Yellow Perch ◽  
Prey Availability ◽  
Juvenile Fish ◽  
Perca Flavescens ◽  
Growth Dynamics ◽  
Model Simulations ◽  
Consumption Rates ◽  
Young Of The Year

Measurements of in situ food consumption and growth rates of young-of-the-year (YOY) yellow perch, Perca flavescens, indicated that extrapolations of the metabolic allometry of adult perch to larval and juvenile perch were inappropriate. YOY active metabolism had the same weight dependent slope as adults but was 4.4 times adult standard respiration. Adult active respiration is typically 1–2 times standard. YOY consumption rates were also higher than predicted from adult allometry. Model simulations demonstrate that consumption and growth dynamics of larval and juvenile fish are more sensitive to variation in temperature and prey availability than are adults.

Cereal Consumption, Production, and Prices in West Pakistan (Notes & Comments)

1968 ◽  
Vol 8 (2) ◽  
pp. 288-306 ◽  
Author(s):  
G. C. Hufbauer
Keyword(s):  
Food Consumption ◽  
Ad Hoc ◽  
Dry Weight ◽  
Small Sample ◽  
Tax Rates ◽  
Active Population ◽  
Early Settlement ◽  
Consumption Rates ◽  
Late Nineteenth ◽  
Better Than

In the late nineteenth and early twentieth centuries, several Punjab Settlement Officers attempted to estimate food consumption rates. These estimates, based on direct observation and ad hoc guesses, were made partly out of academic curiosity, but more urgently, as an aid in establishing the land revenue (i.e., tax) rates. The pre-1926 estimates are summarized in Table I, expressed in pounds of wheat and other foodgrain consumption per person per year1. Broadly speaking, the later, more systemtic observers (e.g., Sir Ganga Ram and C. B. Barry), found lower consumption levels than the earlier observers. It was generally accepted that the rural populace ate better than urban dwellers. Despite the ingenuity of the early Settlement Officers, their compiled estimates suffer from all the difficulties of haphazard small sample observation. Given the revenue purpose of the estimates, they may be biased towards the able-bodied, economically active, population. Further, the very early estimates may have confused dry weight with cooked weight, including water.

Maternal attendance patterns of Steller sea lions (Eumetopias jubatus) from stable and declining populations in Alaska

2003 ◽  
Vol 81 (2) ◽  
pp. 340-348 ◽  
Author(s):  
Linda L Milette ◽  
Andrew W Trites
Keyword(s):  
Prey Availability ◽  
A Priori ◽  
Population Decline ◽  
Perinatal Period ◽  
Eumetopias Jubatus ◽  
Steller Sea Lions ◽  
Sea Lions ◽  
First Feeding ◽  
Attendance Patterns ◽  
The Mean

Maternal attendance patterns of Alaskan Steller sea lions (Eumetopias jubatus) were compared during the summer breeding seasons in 1994 and 1995 at Sugarloaf Island (a declining population) and Lowrie Island (a stable population). Our goal was to determine whether there were differences in maternal attendance between the two populations that were consistent with the hypothesis that lactating Steller sea lions in the area of decline were food-limited during summer. Our a priori expectations were based on well-documented behavioural responses of otariids to reduced prey availability. We found that foraging trips were significantly shorter in the area of population decline, counter to initial predictions. The mean length of foraging trips in the declining area was 19.5 h compared with 24.9 h in the stable area. In contrast, the mean perinatal period (time between parturition and first feeding trip) was significantly longer in the area of decline (9.9 versus 7.9 days), again countering initial predictions. The mean length of shore visits for the declining population was also significantly longer (27.0 h compared with 22.6 h where the population was stable). For both populations, the mean time that mothers foraged increased as pups grew older, whereas the time that they spent on shore with their pups became shorter. Behavioural observations of maternal attendance patterns are inconsistent with the hypothesis that lactating Steller sea lions from the declining population had difficulty obtaining prey during summer.

scholarly journals The reproducibility of subjective appetite scores

1995 ◽  
Vol 73 (4) ◽  
pp. 517-530 ◽  
Author(s):  
Anne Raben ◽  
ANNA TAGLIABUE ◽  
Arne Astrup
Keyword(s):  
Visual Analogue Scale ◽  
Food Consumption ◽  
Analogue Scale ◽  
Prior Experience ◽  
Random Noise ◽  
Normal Weight ◽  
Vas Scores ◽  
The Mean ◽  
The Difference ◽  
Mean Differences

Although subjective appetite scores are widely used, studies on the reproducibility of this method are scarce. In the present study nine healthy, normal weight, young men recorded their subjective appetite sensations before and during 5 h after two different test meals A and B. The subjects tested each meal twice and in randomized order. Visual analogue scale (VAS) scores, 10 cm in length, were used to assess hunger, satiety, fullness, prospective food consumption and palatability of the meals. Plasma glucose and lactate concentrations were determined concomitantly. The repeatability was investigated for fasting values, Δ-mean 5 h and mean 5 h values, Δ-peak/nadir and peak/nadir values. Although the profiles of the postprandial responses were similar, the coefficients of repeatability (CR = 2SD) on the mean differences were large, ranging from 2·86 to 5.24 cm for fasting scores, 1·36 to 1·88 cm for mean scores, 2·98 to 5·42 cm for Δ-mean scores, and 3·16 to 6·44 cm for peak and Δ-peak scores. For palatability ratings the CK values varied more, ranging from 2·38 (taste) to 8·70 cm (aftertaste). Part of the difference in satiety ratings could be explained by the differences in palatability ratings. However, the low reproducibility may also be caused by a conditioned satiation or hunger due to the subjects' prior experience of the meals and therefore not just be a reflection of random noise. It is likely, however, that the variation in appetite ratings is due both to methodological day-to-day variation and to biological day-to-day variation in subjective appetite sensations.

scholarly journals Influence of environmental variables on the feeding and diet of European hake (Merluccius merluccius) on the Mediterranean Iberian coasts

2004 ◽  
Vol 84 (4) ◽  
pp. 831-835 ◽  
Author(s):  
J.E. Cartes ◽  
J. Rey ◽  
D. Lloris ◽  
L. Gil de Sola
Keyword(s):  
Prey Availability ◽  
Western Mediterranean ◽  
Delayed Response ◽  
Feeding Intensity ◽  
Merluccius Merluccius ◽  
Phytoplankton Pigment ◽  
Consumption Rates ◽  
Wet Weight ◽  
European Hake ◽  
Food Consumed

The feeding intensity and the diet of Merluccius merluccius were studied along a 1000 km latitudinal scale on the coasts of the Iberian Peninsula (western Mediterranean) in spring 2000. Merluccius merluccius was distributed along two bathymetric bands corresponding to the deep continental shelf (between 36 to 148 m), and the upper slope (between 215 to 310 m). At the shelf small crustaceans (mainly euphausiids and mysids) were dominant in the diet while fish (mainly Myctophidae) were the preferred prey on the slope. Feeding intensity of hake was significantly higher in areas with higher hake density suggesting feeding aggregations. Also, feeding intensity was significantly correlated with phytoplankton pigment concentrations (ppc), though only with ppc recorded one month before on the hake sampling stations. This delay between ppc and feeding intensity of hake may be a response to higher prey availability, because most hake prey were pelagic in origin (euphausiids, Clupeiformes) and they may reach high densities after exploiting local phytoplankton blooms. This delayed response seems to have more a local or spotted pattern. During three 8-h sampling cycles food consumed by hake ranged between 1·01 to 5·51% body wet weight (BWW), on average within the range of food consumption rates of other benthopelagic, active swimmer, fish.

scholarly journals Contribution of foods consumed away from home to energy intake in Brazilian urban areas: the 2008–9 Nationwide Dietary Survey

2012 ◽  
Vol 109 (7) ◽  
pp. 1276-1283 ◽  
Author(s):  
Ilana Nogueira Bezerra ◽  
Amanda de Moura Souza ◽  
Rosangela Alves Pereira ◽  
Rosely Sichieri
Keyword(s):  
Total Energy ◽  
Energy Intake ◽  
Food Consumption ◽  
Urban Areas ◽  
Total Energy Intake ◽  
Alcoholic Beverages ◽  
Food Groups ◽  
Dietary Survey ◽  
Home Food ◽  
The Mean

The objectives of the present study were to estimate the dietary contribution of away-from-home food consumption, to describe the contribution of away-from-home foods to energy intake, and to investigate the association between eating away from home and total energy intake in Brazilian urban areas. In the first Brazilian Nationwide Dietary Survey, conducted in 2008–9, food records were collected from 25 753 individuals aged 10 years or older, living in urban areas of Brazil. Foods were grouped into thirty-three food groups, and the mean energy intake provided by away-from-home food consumption was estimated. Linear regression models were used to evaluate the association between away-from-home food consumption and total energy intake. All analyses considered the sample design effect. Of the total population, 43 % consumed at least one food item away from home. The mean energy intake from foods consumed away from home was 1408 kJ (337 kcal), averaging 18 % of total energy intake. Eating away from home was associated with increased total energy intake, except for men in the highest income level. The highest percentage of away-from-home energy sources was for food with a high content of energy, such as alcoholic beverages (59 %), baked and deep-fried snacks (54 %), pizza (42 %), soft drinks (40 %), sandwiches (40 %), and sweets and desserts (30 %). The consumption of foods away from home was related to a greater energy intake. The characterisation of away-from-home food habits is necessary in order to properly design strategies to promote healthy food consumption in the away-from-home environment.

scholarly journals Distribution and use of brood-rearing and moulting sites of the Atlantic population of Canada Geese (Branta canadensis) in Nunavik, Quebec

2015 ◽  
Vol 129 (3) ◽  
pp. 229
Author(s):  
Richard C. Cotter
Keyword(s):  
Branta Canadensis ◽  
Hudson Bay ◽  
Canada Geese ◽  
Nesting Ecology ◽  
Brood Rearing ◽  
Atlantic Population ◽  
The Mean ◽  
Shallow Bay ◽  
Over Time ◽  
Coastal Lowlands

The Atlantic population of Canada Geese (Branta canadensis) nests in the coastal lowlands of eastern Hudson Bay and southwestern Ungava Bay in Nunavik, Quebec. Although many aspects of the nesting ecology of this and other northern populations of Canada Geese have been studied and published, there is a paucity of information on the use of brood-rearing and moulting sites. Based on 18 years of band and recapture data from an ongoing banding program, this paper presents the distribution of brood-rearing and moulting sites and the use of these sites over time. Along Hudson Bay and Ungava Bay, the most important brood-rearing and moulting areas are the stretch of coastal lowlands between the Mariet River and Shallow Bay and between Rivière aux Feuilles and Virgin Lake, respectively. Of all adult geese captured during the banding program (n = 41 924), 7.5% (standard error [SE] 0.13%) were recaptures, that is, birds that had previously been caught and banded; annual recapture rates ranged from 5.1% to 11.4%. The mean and median distances between the site of first recapture and the original site of capture were 4.3 km (SE 0.22 km) and 1.5 km, respectively. Juveniles moved, on average, 5.4 km farther than adults and males moved 1.4 km farther than females. Among geese banded as juveniles, males moved twice as far as females: 11.5 km versus 5.7 km.

Feeding Schedule and Daily Food Consumption in Red-Throated Loons (Gavia stellata) over the Prefledging Period

The Auk ◽  
1984 ◽  
Vol 101 (3) ◽  
pp. 593-599 ◽  
Author(s):  
T. E. Reimchen ◽  
Sheila Douglas
Keyword(s):  
British Columbia ◽  
Food Consumption ◽  
Marine Fish ◽  
Average Duration ◽  
Fish Populations ◽  
Feeding Schedule ◽  
Parental Feeding ◽  
Daily Food ◽  
Feeding Activities ◽  
Coastal British Columbia

Abstract We describe parental feeding activities of Red-throated Loons (Gavia stellata) throughout the prefledging period at two freshwater nesting territories in coastal British Columbia. The nesting lake contained resident fish populations, but adult loons fed marine fish to their young, making an average of 11 flights per day (average duration 60 min per flight) to the ocean and returning each time with a single fish. Small shallow-bodied fish (Ammodytidae, Pholidae), which were easily swallowed by chicks, predominated in the diet during the 3 days following hatching. The total weight of fish fed to the chicks per day (8-194 g) increased over the prefledging period: adults returned fewer but larger fish (Embiotocidae) as the chick aged. Of the fish offered, 4% were too large for the chick to swallow.

Sign in / Sign up

Export Citation Format

Share Document