Results
We captured 433 Mops condylurus and 509 Mops pumilusacross the study period, including 391 individual M. condylurus(with 42 recaptures) and 473 individual M. pumilus (with 36
recaptures). The demographic breakdown of bats is given in
Table 1.
The male-to-female ratio of the
population was 1:1.06 for M. condylurus (192 individual males, vs
204 individual females), and 1:1.84 for M. pumilus (169
individual males, vs 311 individual females).
Of the female bats caught over this period, 66 M. condylurus(including 63 individuals) and 142 M. pumilus (including 140
individuals) were gestating. Significantly more gestating than
non-gestating M. condylurus were captured at the beginning of the
pulse (weeks 2-5) (Table 2). Through the middle of pulse (weeks 6-9),
the number of gestating and non-gestating M. condylurus were
comparable. By the end of the pulse (weeks 10-12), significantly moreM. condylurus were not gestating than gestating (Table 2). There
was no consistent directional pattern for gestating versus non-gestatingM. pumilus – there were significantly more gestating females in
weeks 2, 3, and 11, and significantly more non-gestating females in week
7, while numbers of gestating and non-gestating females did not differ
in weeks 4, 5, 9, 10, and 12 (Table 2).
Stage of gestation was not temporally consistent across individual bats
(Figure 2). For M. condylurus , females in early-, medium-, and
late-stage gestation were detected in weeks 1-2 (4 individuals), between
weeks 2-8 (18 individuals), and between weeks 1-10 (58 captures of 55
individuals), respectively. During the month of March, we captured 10M. condylurus at mid-stage gestation, and 20 at late-stage
gestation. The detected duration of early gestation was longer forM. pumilus , spanning the first four weeks (8 individuals).
Females at mid-stage gestation were detected between weeks 2-12 (91
individuals), and late-stage between weeks 1-12 (68 captures of 67
individuals) (Figure 2). Significantly more middle- and late-stage
gestating females were captured from week 2 for both species, compared
to early-stage gestating females (Table 2). However, the number of
early-, mid-, and late-stage gestating M. condylurus did not
differ in weeks 1, 3, 9 and 10, and gestating M. pumilus for
weeks 1, 4, 5, and 7 (Table 2).
In total, 124 and 200 lactating M. condylurus and M.
pumilus were captured (116 and 191 individuals, respectively), with
captures of lactating bats spanning nearly the entire study period for
both species (weeks 1-12 and 2-12, respectively) (Figure 2). Of these,
58 (55 individuals) and 111 (109 individuals) were gestating while
lactating. All stages of gestation (early, mid, and late) were observed
in lactating bats, for both species (Table 3). Females that were
simultaneously lactating and gestating were most often caught between
weeks 2-8 for M. condylurus (Table 2). For M. pumilus ,
females that were simultaneously lactating and gestating were most often
caught between weeks 2-4, though the first lactating non-pregnant female
was captured during week 2 (5th February) (Table 2).
The duration between the first lactating non-pregnant M.
condylurus (potentially indicative of the first parturition and start
of the birth pulse) and the last gestating M. condylurus(indicative of the last parturition and end of the birth pulse) was
~8.5 weeks in our study (30th January
– 31st March) (Table 2). For M. pumilus ,
gestating females were captured continuously throughout the study
period, up to and including the last week of capture, week 12
(14th April). It is likely that the full birth pulse
of M. pumilus was not captured during the study period (Table 2).
Non-reproductive adult females were caught over the entire duration of
the study, for both species (Table 2). This included 30 captures of 29
individual M. condylurus , and 31 captures of 29 individualM. pumilus . To be conservative in this estimate, non-gravid
females with engorged but non lactating nipples (i.e., post-lactating
females) were not classified as non-reproductive, even though they may
have reproduced in the previous birth pulse only.