Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 91 for “"Clutch size"”.
-
Does nest size constrain clutch size? A tropical-temperate test
The smaller clutch size of tropical as opposed to north temperate birds has intrigued researchers for a long time. An untested hypothesis posits that higher nest predation in the tropics favors smaller nests thereby constraining clutch-size. We tested this hypothesis by conducting an experiment to …
-
Does nest size constrain clutch size? A tropical-temperate test
The smaller clutch size of tropical as opposed to north temperate birds has intrigued researchers for a long time. An untested hypothesis posits that higher nest predation in the tropics favors smaller nests thereby constraining clutch-size. We tested this hypothesis by conducting an experiment to …
-
Fitness Consequences of Clutch Size Decisions and Mate Change in Black Brant
… chapter, I used experimental manipulations of clutch and broods sizes (i.e., the number of goslings leaving the nest) to understand if the maximal clutch size laid by brant (i.e., 5 eggs) is under ultimate control as a result of tradeoffs between reproduction and residual reproductive value of …
-
Ecological and Evolutionary Consequences of Variation in Clutch Size in Asteromyia Carbonifera (o.s.) (Diptera: Cecidomyiidae)
… laid at each ovipositional site is termed the "clutch size." Midge larvae are potential hosts to five species of hymenopterous parasitoids. Three aspects of the plant/gall-maker/parasitoid community are examined in light of current theories in evolutionary ecology: (1) the selective pressures …
-
Consequences of avian parental incubation behavior for within-clutch variance in incubation temperature and offspring behavioral phenotypes
… species to investigate how factors (disturbance, clutch size, ambient temperature) that influence parental demands may affect parental incubation behavior, physiology, and egg temperatures, and subsequently how egg temperatures affect offspring behavior and physiology. In a field experiment, I …
-
Lifetime fitness and changing life history traits in Red-cockaded Woodpeckers
… of attaining breeding status; and lay date, clutch size, age at first reproduction, and variance in clutch size affecting lifetime fitness. I also found that many traits were changing over time including lay date, clutch size, partial brood loss, and survival to year one. These traits were …
-
Reproduction and Movement Patterns of the Common Snapping Turtle (Chelydra Serpentina) Inhabiting a Hypothermic Reservoir in Southwest Missouri
… different for the two sites (P > 0.05). Mean clutch size and relative clutch mass were significantly larger for the Rockaway Beach population (P < 0.05). Egg mass did not vary with plastron length at either site. Clutch size and clutch mass increased with plastron length within both …
-
Annual Reproductive Potential, Diet, and Growth of the Map Turtle, Graptemys Geographica (Le Sueur)) in a Missouri Stream
… 18 females indicate that two-thirds laid two clutches of eggs annually and one-third laid three. The average clutch size is 10.1. The annual reproductive potential is 23.3. Age and minimum size at maturity are tentatively estimated at 3 years, 60mm plastron length for males, and 9-10 years, …
-
Effects of Habitat Quality on Reproduction in Two Georgia Populations of Gopherus Polyphemus
… or between populations? (3) Is female body size shaping egg size and/or clutch size for either population? (4) Are females providing equal resources to hatchlings and is hatchling growth potentially being modified by habitat quality affecting adult size and age to sexual maturity? Tortoises …
-
Senescencia, parasitismo, inmunidad y éxito reproductor en el Avión Común (Delichon urbica Linneo 1758)
… by blood parasites infections, by influencing clutch size, or by producing an energetic cost in inmune response. Infection increases as a consecuence of inmunological deterioration with age. Yolk androgen allocation depends on female body condition.
-
Seasonal variation in the reproductive biology of the ring -billed gull (Larus delawarensis)
… Park, Ontario, in 1976 and 1977. Early started clutches (comprising the majority of clutches on Gull Island) in 1977 produced more chicks per nest (2.20 ± 0.09) than late started clutches (0.86 ± 0.13) as a result of reductions in mean clutch size, hatching success and fledging success with date …
-
REPRODUCTIVE CHARACTERISTICS OF AMERICAN COOTS (FULICA AMERICANA) IN NORTHERN ARIZONA.
… in spikerush at seasonal wetlands laid larger clutches than coots nesting in bulrush at the semipermanent wetland. Better nesting success was related to better vegetative concealment of the nest from crows and ravens. Smaller territories and larger eggs among nests in bulrush were related to …
-
Productivity of A Resident Giant Canada Goose Flock in Northeastern South Dakota
… were used by geese as nesting sites. Mean clutch size of completed nests was 5.14 in 1974 and 5.26 in 1975. Mean clutch size was 5.38 on ANS and 4.89 on NNS for the 2-year study. At least one egg hatched in 87 percent of the 283 nests located during the study. Larger clutches had a higher …
-
Theory and Pattern of Life-History Evolution in Passerine Birds
… in life-history traits among species were hypothesized to result from the interacting effects of mortality expressed as within-brood survivorship of offspring (resource effects), total breeding failure (nest predator effects), adult non-reproductive mortality, and adult reproductive risk. …
-
Summer and Fall Ecology of Gray Patridge in Eastern South Dakota
… of Brookings. Nesting habitats, success, and clutch size were determined from 44 randomly located nests. Most nests (91%) were in grassy roadsides and fencerows. Few birds nested in cover dominated by legume vegetation. Average clutch size of completed nests was 17.8 eggs and nest success was …
-
The Allometry of Giant Flightless Birds
… in estimating avian body mass. The small sample size of extant ratites makes mass estimate extrapolation to larger extinct species inaccurate. The division of ratites into cursorial and graviportal groups is supported. Aepyornithids do not show atypical femoral shaft asymmetry. New and more …
-
Sexual conflict and division of labour during incubation
… breeding attempt. In the second attempt, clutch size was negatively related to the amount of time spent incubating the first clutch in females that had previously fledged a large brood. I also found that the number of offspring surviving to maturity increased with total incubation …
-
Reproductive limitation in coastal ospreys (Pandion haliaetus): an ecological and an evolutionary perspective
… patterns in this species, especially clutch-size and laying date. Reduced food delivery to nests increased nestling loss. Reproductive loss was especially high in Florida where latitude and season restricted daylight foraging time for the providing male parent. Starvation of smaller, …
-
Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island
… fledged, fledging period, hatching success, clutch size, and chick fledging weight. Hatching success, clutch size, and fledging weight were not influenced by the mass of either parent. There was a trend of shorter fledging periods as the mass of the heavier parent increased. The greatest …
-
Aspects of the foraging and breeding ecology of the Southern African Kestrel, Falco tinnunculus rupicolus
… success and diet) and breeding parameters (clutch size, hatching and fledging success, nestling, fledging and post-fledging periods) of the Southern African Kestrel. These parameters were compared to those from studies made on the European Kestrel (Falco tinnunculus tinnunculus) in western …
Page 1 of 5