I located 105 effective nests, generally when you are riding more sluggish along the land
During the for each and every reproduction seasons we sought out nests intensively everywhere the study web site. I adopted the destiny of any nest before eggs hatched or the nest were unsuccessful. Nests was basically visited anywhere between 0900 and you can 1700 period plus the visits endured two hundred yards from the nest, ranging from 1000 and you will 1700 days. Period of the brand new focal findings varied regarding 31 minute to eight h, together with full lifetime of observation was 29.5 h. Given that our observations ranged in length there had been times in the that your men was at the nest for hours, in order to guess brand new portion of nest attention i pooled the latest focal findings out of nests that were at the same stage from incubation.
Because the males are Japon kГјltГјrГј partner ebeveynler more likely to wilderness the colony when disrupted during the an early stage of nesting duration ( Fernandez and you may Reboreda 2000), we monitored a lot of the nests (9 of 11 circumstances totaling 34 colony-days) while in the mid- or late incubation
The thermistor of the temperature logger was introduced in a fresh natural orphan egg (unattended eggs laid far from active nests; Navarro et al. 1998) through a small hole in the equatorial plane and fixed to the eggshell with epoxy adhesive. The egg was attached to the center of the nest and the data logger was hidden under the nest. The data logger automatically recorded the temperature at 3.8 or 6 min intervals during four or six days, respectively. We monitored egg temperatures in those 11 nests totaling 40 nest-days. In the other two cases we started the monitoring of the nest three and five days after the laying of the first egg. None of the nests used for monitoring male activity was deserted. We used the decrease in egg temperature to determine when the male left the nest ( Hainsworth et al. 1998, Flint and Grand 1999). We previously estimated egg cooling-rate of Greater Rhea eggs by heating six fresh eggs up to 33°C and then placing them in an environment at a temperature of 25°C, similar to temperatures registered in our study area between 1100 and 1300 hours (the warmest time of the day). We estimated egg cooling-rate by dividing the initial difference in temperature between eggs and the environment by the time elapsed until eggs reached a thermal equilibrium with the environment. The estimated egg cooling-rate for a temperature gradient of 8°C was 0.063 ± 0.01°C min ?1 . We assumed that the male left the nest when the difference in egg temperature was |T(t) ? T(t?1)| > 1°C, where T(t) and T(t?1) are egg temperatures at a time interval of 15 min when data loggers were set at 3.8 min intervals or 18 min when they were set at 6 min intervals. We considered that the male was outside the nest since the time at which the difference between T(t) and T(t?1) was negative until the time it was positive (i.e. the male resumed incubation). Although the sun can heat eggs when the male is absent (particularly at midday), unattended eggs never reached temperatures >30°C (see below). Therefore, it was possible for us to discriminate between an increase in temperature produced by the Sun and one produced by males when they resume incubation.
I in addition to measured version inside the eggs temperatures inside about three fresh nests (nests instead men focus). We utilized nests that had been in the past left behind just like the experimental nests. Within the for each and every nest (clutch designs regarding sixteen, 21, and you can 23 eggs) we fixed one-egg having a beneficial thermistor in to the, into cardio of the colony similarly that i did into the effective nests (see a lot more than).
