Breeding periods of Gerbillus cheesmani (Rodentia, Muridae) in Saudi Arabia

Abstract

In deserts, rainfall is rare and often irregular, and this directly conditions the growth, flowering and fruiting of plants. Consequently, food can become seasonally scarce for plant-eating vertebrates. The relationship between the reproduction of rodents, rainfall, and plant production has been partly studied in some Asian and African desert regions, but not in Saudi Arabia. We therefore sought to define the breeding periods of the most common rodent in that country, Gerbillus cheesmani . More than 540 specimens were collected during 16 consecutive months between November 2001 and February 2003. As expected, the reproduction of mature males and females showed significant monthly variation directly correlated to rainfall. Most young were captured 2 months after the peak in pregnancy. The reproduction of this species was clearly seasonal in Saudi Arabia, unlike other desert regions where many rodents reproduce more or less throughout the year. Furthermore, both sexes reproduced synchronously, whereas in most other countries, males become reproductive 1 -2 months before females. Lastly, reproduction coincided with the rainfall during the study period, but not with the average pluviosity of the country. This indicates that all the individuals responded quickly to the local conditions.

Reproductive patterns in the Baluchistan gerbil, Gerbillus nanus (Rodentia: Muridae), from western Saudi Arabia: The role of rainfall and temperature

“…Cheesman's gerbil where male and female cue into rainfall and synchronise reproduction (Henry and Dubost, 2012), in the Baluchistan gerbil, males are activated by rainfall while females appear to be in reproductive readiness for much of the year in Taif, Saudi Arabia. …”

“…However, photoperiod does not play such an important cue in desert and semi-desert environments where the correlation between photoperiod and food availability is often not so clear cut (Henry andDubost, 2012, Breed andLeigh, 2011).Deserts experience extreme ranges in daily and seasonal ambient temperatures, with little or no rainfall, intense solar radiation and have a minimal primary productivity (Schmidt-Nielsen, 1964). These habitats have sparse vegetation and the soil substrate is exposed to the full rays of the sun and rainfall is often unpredictable.Consequently, mammals occupying these regions are prone to desiccation and must regulate both their water balance and energy tightly (Macfarlane, 1968).Similarly, reproduction in desert ecosystems may be difficult to achieve because of the scarceness and unpredictability of rainfall, extreme daily and seasonal temperature ranges and the associated general lack of available food resources (Reichman and Graff, 1973).…”

“…Henry and Dubost (2012) studied Cheesman's gerbil, Gerbillus cheesmani from the southwestern part of Saudi Arabia and found it to cue its reproduction with precipitation. Indeed reproduction is highly seasonal with both males and females synchronizing their reproduction to the short period of rainfall, rapidly producing offspring that can benefit from the short periods of food abundance.…”

Characterizing the reproductive transcriptomic correlates of acute dehydration in males in the desert-adapted rodent,Peromyscus eremicus

“…The integral role of water as a reproductive cue for desert-rodents has also been demonstrated in water-supplementation studies (reviewed in [45,50]) as well as research on the effects of desert rainfall [51][52][53][54]. Thus, Schwimmer and Haim [46] asserted that reproductive timing is the most evolutionarily important adaptation for desert rodents.…”

“…Furthermore, watersupplementation studies among wild desert rodents resulted in prolonged breeding seasons in the hairyfooted gerbil and the four-striped grass mouse, but not in the Cape short-eared gerbil [50]. Recent research has confirmed the importance of rainfall as a reproductive cue in the Arabian spiny mouse [51], the Baluchistan gerbil [52], Chessman's gerbil [53] and the Spinifex hopping mouse [54]. The focus of this previous research was to investigate reproductive cues and consequences of water-limitation in desert rodents, namely how species have adapted breeding onset and cessation patterns to respond to water availability.…”