Analysis Of The Typical Breeding Season Of Eastern Bluebirds

The typical breeding season of Eastern Bluebirds typically begins when they lay their first egg around the beginning of April and their last egg towards the final days of that month (Hall, 2013). The nestlings will not start fledging until early May, although there is variation until early September. We understand from researching the process of fecal sac removal that the fecal sacs will most likely not be removed until the first few weeks after hatching. The longer days of late spring and early summer have a photoperiod average of 16-18 hours of daylight and we since we plan to conduct this experiment in April of 2017, 18 hours of daylight will be the expected May photoperiod by the time the birds hatch (Navara, 2016).The normal temperatures of May average from the lows of 14.6 ℃ to 27.7℃ (U.S. …show more content…
This will allow scientists to see what percentage of each sex is involved with removing fecal sacs. Also, the time in which the most fecal sacs are removed (i.e. initial post hatch vs. later) will be significant to see if feeding frequency has any correlation to fecal sac removal. As the birds grow larger and as more of the nestlings hatch, more food and feeding trips will be necessary to support growth. Basal hormones will be taken from male birds at the beginning of the experiment from all birds via blood samples. At the height of incubation, which we expect to be early to mid May, all birds in the prolactin implantation group will have their blood samples taken to compare hormone levels in males verses females. This will be used for comparison at the end of the experiment. Out of the three groups we are using, only the two experimental gorups will be given prolactin implants and within these groups, only the males will receive the implants (20 total