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Parental self-feeding effects on parental care levels and time allocation in Palestine sunbirds.

Markman S - PLoS ONE (2014)

Bottom Line: Until now the effect of food consumption by parent birds on their food delivery to their young as well as other parental activities has rarely been studied.Nestling food intake and growth rate increased with increasing food quality of parents and decreasing brood size.These results imply that increasing the nutrient content of foods consumed by parent sunbirds allow them to increase the rate at which other foods are delivered to their young and to increase the time spent on other parental care activities.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Environment, University of Haifa - Oranim, Tivon, Israel.

ABSTRACT
The trade-off between parents feeding themselves and their young is an important life history problem that can be considered in terms of optimal behavioral strategies. Recent studies on birds have tested how parents allocate the food between themselves and their young. Until now the effect of food consumption by parent birds on their food delivery to their young as well as other parental activities has rarely been studied. I have previously shown that parent Palestine sunbirds (Nectarinia osea) will consume nectar and liquidized arthropods from artificial feeders. However, they will only feed their young with whole arthropods. This provided a unique opportunity to experimentally manipulate the food eaten by parents independent of that fed to their offspring. Here, I hypothesized that parents invest in their current young according to the quality of food that they themselves consume. Breeding pairs with two or three nestlings were provided with feeders containing water (control), sucrose solution (0.75 mol) or liquidized mealworms mixed with sucrose solution (0.75 mol). As food quality in feeders increased (from water up to liquidized mealworms mixed with sucrose solution): 1) Parents (especially females) increased their food delivery of whole arthropod prey to their young. 2) Only males increased their nest guarding effort. Nestling food intake and growth rate increased with increasing food quality of parents and decreasing brood size. These results imply that increasing the nutrient content of foods consumed by parent sunbirds allow them to increase the rate at which other foods are delivered to their young and to increase the time spent on other parental care activities.

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The number of parental visits per nestling per hour (means ± SE) by Palestine sunbirds plotted against brood size (2 or 3 nestlings), and quality of food available in an artificial feeder, which was either water (Water), sucrose solution (Sugar) or sucrose and mealworm solution (Sugar and worms).The values consist of the average for the whole seven days of the manipulation period (from nestlings being 7 days of age until 13 days of age) for each parent.
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pone-0113890-g004: The number of parental visits per nestling per hour (means ± SE) by Palestine sunbirds plotted against brood size (2 or 3 nestlings), and quality of food available in an artificial feeder, which was either water (Water), sucrose solution (Sugar) or sucrose and mealworm solution (Sugar and worms).The values consist of the average for the whole seven days of the manipulation period (from nestlings being 7 days of age until 13 days of age) for each parent.

Mentions: After testing for the number of parental visits and time spent at the nest during these feeding visits, I tested for differences in the number of parental visits per nestling and found that the number of feeding visits per nestling increased significantly with increasing food quality in the feeder and with decreasing brood size (all Tukey HSD tests p<0.01; Table 3a, Fig. 4). Although the total number of visits to the larger broods was higher than to the smaller broods, the number of visits per nestling was significantly lower in broods of three than in broods of two (all Tukey HSD tests p<0.001; Table 3a, Fig. 4). However, parents who reared three nestlings and were fed on sucrose solution had similar delivery rates of arthropods per nestling to parents who reared only two nestlings but were offered water in feeders (Tukey HSD test, p = 0.476). Furthermore, parents who reared three nestlings and were provided with sucrose and mealworm solution had higher delivery rates of arthropods per nestling than parents who reared only two nestlings, but were offered water in feeders (Tukey HSD test, p<0.001).


Parental self-feeding effects on parental care levels and time allocation in Palestine sunbirds.

Markman S - PLoS ONE (2014)

The number of parental visits per nestling per hour (means ± SE) by Palestine sunbirds plotted against brood size (2 or 3 nestlings), and quality of food available in an artificial feeder, which was either water (Water), sucrose solution (Sugar) or sucrose and mealworm solution (Sugar and worms).The values consist of the average for the whole seven days of the manipulation period (from nestlings being 7 days of age until 13 days of age) for each parent.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4256214&req=5

pone-0113890-g004: The number of parental visits per nestling per hour (means ± SE) by Palestine sunbirds plotted against brood size (2 or 3 nestlings), and quality of food available in an artificial feeder, which was either water (Water), sucrose solution (Sugar) or sucrose and mealworm solution (Sugar and worms).The values consist of the average for the whole seven days of the manipulation period (from nestlings being 7 days of age until 13 days of age) for each parent.
Mentions: After testing for the number of parental visits and time spent at the nest during these feeding visits, I tested for differences in the number of parental visits per nestling and found that the number of feeding visits per nestling increased significantly with increasing food quality in the feeder and with decreasing brood size (all Tukey HSD tests p<0.01; Table 3a, Fig. 4). Although the total number of visits to the larger broods was higher than to the smaller broods, the number of visits per nestling was significantly lower in broods of three than in broods of two (all Tukey HSD tests p<0.001; Table 3a, Fig. 4). However, parents who reared three nestlings and were fed on sucrose solution had similar delivery rates of arthropods per nestling to parents who reared only two nestlings but were offered water in feeders (Tukey HSD test, p = 0.476). Furthermore, parents who reared three nestlings and were provided with sucrose and mealworm solution had higher delivery rates of arthropods per nestling than parents who reared only two nestlings, but were offered water in feeders (Tukey HSD test, p<0.001).

Bottom Line: Until now the effect of food consumption by parent birds on their food delivery to their young as well as other parental activities has rarely been studied.Nestling food intake and growth rate increased with increasing food quality of parents and decreasing brood size.These results imply that increasing the nutrient content of foods consumed by parent sunbirds allow them to increase the rate at which other foods are delivered to their young and to increase the time spent on other parental care activities.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Environment, University of Haifa - Oranim, Tivon, Israel.

ABSTRACT
The trade-off between parents feeding themselves and their young is an important life history problem that can be considered in terms of optimal behavioral strategies. Recent studies on birds have tested how parents allocate the food between themselves and their young. Until now the effect of food consumption by parent birds on their food delivery to their young as well as other parental activities has rarely been studied. I have previously shown that parent Palestine sunbirds (Nectarinia osea) will consume nectar and liquidized arthropods from artificial feeders. However, they will only feed their young with whole arthropods. This provided a unique opportunity to experimentally manipulate the food eaten by parents independent of that fed to their offspring. Here, I hypothesized that parents invest in their current young according to the quality of food that they themselves consume. Breeding pairs with two or three nestlings were provided with feeders containing water (control), sucrose solution (0.75 mol) or liquidized mealworms mixed with sucrose solution (0.75 mol). As food quality in feeders increased (from water up to liquidized mealworms mixed with sucrose solution): 1) Parents (especially females) increased their food delivery of whole arthropod prey to their young. 2) Only males increased their nest guarding effort. Nestling food intake and growth rate increased with increasing food quality of parents and decreasing brood size. These results imply that increasing the nutrient content of foods consumed by parent sunbirds allow them to increase the rate at which other foods are delivered to their young and to increase the time spent on other parental care activities.

Show MeSH