Aims: To find out whether the fatter and smaller moorhen males (which are preferred by females as mates) are also healthier.
Location: Southwestern Andalusia (southern Spain).
Methods: Analysing the variation in time along the autumn and winter of the extent of the fat reserves of adult male moorhens. In the period preceding pair formation (February 2003), the relationship was obtained between body size (represented by tarsus length) and an effective index of fat reserves (body mass x tarsus length-3) with tarsi fluctuating asymmetry, haematocrit, leukocyte index, heterophil/lymphocyte ratio and albumin/globulins ratio.
Results: The extent of the fat reserves decreases during the autumn and winter. The heterophil/lymphocyte ratio was found to be significantly and positively related to body size, and negatively so to the fat index. In addition, the fat index was found to be significantly and negatively related to tarsi fluctuating asymmetry.
Conclusions: The findings that preferred fatter males are more symmetrical, and that these fatter males, as well as those of smaller size, are healthier with respect to the heterophil/lymphocyte ratio point to the election of male mates, not only for the benefits derived from maintaining incubation, but also of good health.
