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We studied the sex ratio of goitered gazelles in the naturally arid environment of Kazakhstan over a 6-year period. The main methods in our study were taking transect counts and focal observations. The sex ratio of adult goitered gazelles has demonstrated a female bias due to a much higher mortality of males of all ages, especially during years with unusually severe winters. This phenomenon is typical for many polygynous ungulates, as well as other gazelle species. Surprisingly, our data demonstrated monthly fluctuations in sex proportions, along with a bias shift from a female-dominant population during most of the year to a male-dominant population during spring. We discovered, though, that our data did not reflect any real changes in the sex ratio of the population but, instead, revealed the radical changes in behavior of pregnant females before giving birth—hiding from danger in thick shrubs or broken terrain rather than fleeing. As a result, we were not able to see many pregnant females in our spring samples (before birthing), and so received a male-biased population. During the rest of the year (after birthing), females returned to their usual behaviors of fleeing from danger that then gave us a female-biased sex ratio that reflected a more accurate status in sex proportions of the population. So, our results discovered seasonal sex difference in hiding behavior which led to a bias based on visibility.
Apart from the purely physiological excretion function, many mammals use their own urine and feces as reliable, odoriferous signals to indicate territorial occupancy. Marking is especially important for many antelopes, as territoriality is linked to reproductive success in these species. Scent marking with excrement, though, imposes physiological constraints in the amounts of urine and feces they can produce for these acts. Some male antelopes have been found to be able to regulate the size of their fecal marks, increasing marking frequency and decreasing the volume per defecation deposit compared to that of females. In this paper, we investigate quantitative characteristics of urination-defecation acts in goitered gazelles (Gazella subgutturosa), such as excretion frequency and duration, and explain potential differences in urine and fecal marking behavior for goitered gazelles based on sex, age, season, and territorial status. Our study found that frequency of urination-defecation acts in adult males fluctuated significantly over seasons and was highest in males during the rut, while subadult males urinated-defecated more rarely and with longer acts of urination than adults. In contrast, females (both adult and subadult) urinated and defecated at the same rate without significant seasonal changes. During the rutting period, urination duration in adult males decreased significantly with the rate increasing but even then, urination duration was longer than in females; defecation duration, on the other hand, remained relatively stable in adult males over months compared to urination duration, irrespective of rate. This finding is contradictory to the “material (urine and feces) saving hypothesis” as found for male oribi (Ourebia ourebi). We also discovered that in contrast to females and non-territorial males, territorial goitered gazelle males intensively ate snow during the rut, likely to compensate for water loss during their vigorous urination marking activity. The stability in defecation duration in adult and subadult males, however, regardless of seasonal changes in rate, was difficult to explain.
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