Rutting vocal display in male impala (Aepyceros melampus) and overlap with alarm context

Table 3 Values (mean ± SD) of acoustic variables of the three types of male impala snorts

Snort variable	All snorts n = 181	Usual snorts n = 77	Roar-snorts n = 66	Alarm snorts n = 38	GLM snort type effect	GLM recording site effect
Dur (s)	0.39 ± 0.15	0.42 ± 0.15 ^a	0.43 ± 0.14 ^a	0.28 ± 0.09 ^b	F_2,172 = 15.5, p < 0.001	F_6,172 = 1.58, p = 0.15
fpeak (Hz)	1070 ± 566	1066 ± 598	997 ± 547	1207 ± 517	F_2,172 = 1.64, p = 0.18	F_6,172 = 2.55, p = 0.02
q25 (Hz)	1103 ± 277	1113 ± 275	1050 ± 258	1177 ± 300	F_2,172 = 2.40, p = 0.10	F_6,172 = 2.88, p = 0.01
q50 (Hz)	1995 ± 487	2103 ± 504	1935 ± 428	1879 ± 513	F_2,172 = 2.63, p = 0.08	F_6,172 = 1.15, p = 0.34
q75 (Hz)	3363 ± 734	3462 ± 581 ^a	3532 ± 763 ^a	2870 ± 766 ^b	F_2,172 = 11.0, p < 0.001	F_6,172 = 2.31, p = 0.04
Int (s) ^a	3.10 ± 7.06	0.56 ± 0.32 ^a	0.42 ± 0.23 ^a	13.13 ± 10.79 ^b	F_2,146 = 80.7, p < 0.001	F_6,146 = 1.56, p = 0.16

Designations: Dur call duration, fpeak the peak frequency with maximum amplitude, q25, q50, q75 the lower q25, medium q50, and upper q75 quartiles, covering 25, 50 and 75% of the energy of the call spectrum, Int Interval to the next call within bout or series, GLM GLM results, significant differences are given in bold. The same superscripts indicate that the values did not differ significantly (Tukey HSD test)
^an = 58 for the usual snorts, n = 65 for the roar-snorts, n = 32 for the alarm snorts

ISSN: 1742-9994