Effects of Electromagnetic Fields on the Reproductive Success of American Kestrels

2000 ◽  
Vol 73 (1) ◽  
pp. 60-65 ◽  
Author(s):  
Kimberly J. Fernie ◽  
David M. Bird ◽  
Russell D. Dawson ◽  
Paul C. Laguë
Keyword(s):  
Reproductive Success ◽  
Electromagnetic Fields ◽  
American Kestrels

scholarly journals Reproductive Success of American Kestrels: The Role of Prey Abundance and Weather

The Condor ◽  
2000 ◽  
Vol 102 (4) ◽  
pp. 814-822 ◽  
Author(s):  
Russell D. Dawson ◽  
Gary R. Bortolotti
Keyword(s):  
Reproductive Success ◽  
Natural Variation ◽  
Weather Conditions ◽  
Prey Abundance ◽  
Offspring Size ◽  
Minimum Threshold ◽  
Provisioning Behavior ◽  
American Kestrels ◽  
Parental Provisioning

Abstract We investigated how natural variation in abundance and availability of the main prey of American Kestrels (Falco sparverius), small mammals, influenced provisioning rates by parents, and offspring size and survival. Provisioning behavior of kestrels was not constrained by the abundance of food in the environment; however, the availability of food, mediated through variation in weather, appeared to significantly influence parental provisioning behavior. Moreover, variation in weather had clear effects on reproductive success because nestlings exposed to inclement weather were smaller and lighter at fledging, and less likely to survive to fledging, compared to nestlings raised during good weather conditions. Prey abundance was not related to offspring size or survival. Our results suggest American Kestrels are limited by the availability, as opposed to abundance, of food on territories. It is likely that during our study, prey abundance was above some minimum threshold necessary to support successful reproduction, and so variation in weather affected reproduction more than variation in prey abundance.

scholarly journals Effects of Electromagnetic Fields on the Growth of Nestling American Kestrels

The Condor ◽  
2000 ◽  
Vol 102 (2) ◽  
pp. 461-465 ◽  
Author(s):  
Kimberly J. Fernie ◽  
David M. Bird
Keyword(s):  
Weight Gain ◽  
Electromagnetic Fields ◽  
Transmission Lines ◽  
Bone Growth ◽  
Growth Patterns ◽  
Laboratory Setting ◽  
Male And Female ◽  
Maximal Weight ◽  
American Kestrels ◽  
In The Wild

AbstractWe studied nestling American Kestrels (Falco sparverius) in a laboratory setting to determine whether exposure to electromagnetic fields (EMFs) affected their growth. Captive nestlings were raised by their parents under control or EMF conditions similar to those occurring near transmission lines in the wild. Nestlings also were exposed to EMFs as embryos when incubated by their parents. Measurements of body mass, and lengths of tarsi, antebrachia, and feathers were taken every three days after hatching. EMF exposure affected the growth of female and male nestlings. EMF nestlings and fledglings were heavier and had longer tarsi. The periods of maximal weight gain and antebrachial growth were delayed in EMF males compared to controls, although EMF males were heavier and had similarly long antebrachia to controls by 21 days of age. Growth of ninth primaries and central rectrices of nestlings were unaffected by EMF exposure. Growth patterns of male and female kestrel nestlings were similar to those previously reported for this species, although the periods of maximal weight gain and bone growth did not occur earlier in EMF males than females as it did in controls.

Environmentally Relevant Concentrations of DE-71 and HBCD Alter Eggshell Thickness and Reproductive Success of American Kestrels

2009 ◽  
Vol 43 (6) ◽  
pp. 2124-2130 ◽  
Author(s):  
Kim J. Fernie ◽  
J. Laird Shutt ◽  
Robert J. Letcher ◽  
Ian J. Ritchie ◽  
David M. Bird
Keyword(s):  
Reproductive Success ◽  
Eggshell Thickness ◽  
American Kestrels

Reproductive performance of American Kestrels laying replacement clutches

1985 ◽  
Vol 63 (11) ◽  
pp. 2590-2593 ◽  
Author(s):  
Reed Bowman ◽  
David M. Bird
Keyword(s):  
Reproductive Success ◽  
Reproductive Performance ◽  
Falco Sparverius ◽  
Nestling Growth ◽  
Fledging Success ◽  
American Kestrels ◽  
First Clutch ◽  
Second Clutch

Egg dimensions, nestling growth, and reproductive success were compared between first and second clutch nests of American Kestrels (Falco sparverius) to determine the influence of renesting on fledging success. Eggs were removed from 11 nests during 1982–1983. Eight nests served as controls. Most pairs (81.8%) renested on their original territory. We found no significant differences in egg dimensions, fertility, or hatchability between the two groups. Second clutch males (n = 6 clutches) were smaller at hatching than males from first clutches (n = 8 clutches). By day 24 these males (n = 5 clutches) were heavier, with significantly longer manus and antebrachia than first clutch males (n = 3 clutches). However, five of eight first clutch nests fledged all males before day 24. Males remaining in first clutch nests beyond day 24 were lighter with significantly smaller antebrachia by day 18 than males fledging before day 24. This may have biased our comparisons between first and second clutch males. No significant differences in growth were found between female groups. First-clutch progeny fledged significantly younger than second-clutch birds. Males fledged earlier than females in first clutches, but the sexes fledged simultaneously in second clutches.

The Flame Retardant β-1,2-Dibromo-4-(1,2-dibromoethyl)cyclohexane: Fate, Fertility, and Reproductive Success in American Kestrels (Falco sparverius)

2012 ◽  
Vol 46 (15) ◽  
pp. 8440-8447 ◽  
Author(s):  
Sarah C. Marteinson ◽  
Robert J. Letcher ◽  
Laura Graham ◽  
Sarah Kimmins ◽  
Gregg Tomy ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Flame Retardant ◽  
Falco Sparverius ◽  
American Kestrels

Effects of Electromagnetic Fields on Body Mass and Food-Intake of American Kestrels

The Condor ◽  
1999 ◽  
Vol 101 (3) ◽  
pp. 616-621 ◽  
Author(s):  
Kimberly J. Fernie ◽  
David M. Bird
Keyword(s):  
Food Intake ◽  
Electromagnetic Fields ◽  
Body Mass ◽  
American Kestrels
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