Summary of Clutch Loss

If you lose the clutch, it affects the operating sex ratio (OSR) of Dendrobates pumilio. OSR is the ratio of male to female that is suitable for mating. As women spend more time on their parents' responsibilities, the proportion of men in the mating pool usually gets higher. Factors that affect OSR include whether available food and nesting sites, ambient temperature, and whether one sex is greater than the other. Losing the clutch also affects the OSR.

Table 2 summarizes the timing of major breeding events in 2nd Mountain Bluebird. It was in the southern part of the lowland that we arrived at the breeding ground and began producing the clutch. In most areas, there is a long time (at least 1 month) from arrival at the breeding ground to the beginning of the clutch. Most of the first clutch will be laid in May and the second clutch will be laid in late June or early July when tried (Barrett 1998). Breeding success depends on spring / summer climatic conditions, low in dry, warm conditions, high in wet, cold conditions (Power 1974, Power and Lombardo 1996). Eggs, chicks, chicks, and even adults may show considerable mortality rates when freezing is slow, or when cold and humid weather continues (Haecker 1948, Lane 1971, Scott and Lane 1974, Houston 1982 , Power and Lombardo 1996). ) Power (1974) has recorded breeding success rate in Montana for many years.

In stark contrast to the two-year results in the eastern part of British Columbia, 32% of the 13 pairs completed the second operation within one year, 14 of the second year did not attempt a second surgery It was. In some cases, a third clutch can be placed, but this only occurs if the first or second clutch fails (Power and Lombardo 1996). As explained elsewhere in this evaluation, Takayama's ecology and conservation analysis is complicated for the dissemination of nest box research data. One of the main concerns when interpreting data from these studies is that pairing in the box may result in very high reproductive success rates (Purcell et al., 1997) . A study of Blue Bird closest in British Columbia supports this view; the overall success rate of nests (the success rate of nests to at least one youth) is 71% of nest boxes (884 in 1233) 62% of natural caves (36 out of 58) (Campbell et al. 1997)