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โครงการรวบรวมและจัดทําเอกสารวารสารอิเล็กทรอนิกส์ มหาวิทยาลัยเกษตรศาสตร์

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that they already recognized the risk of predation as presented by loud speakers, the responses of
birds were compared using statistical t-test analysis.

Primary Responses
Distress calls of the White-vented myna made alerted the Common myna to the possible
presence of danger. The Common myna responded by stretching the neck and turning the head

quickly in the first period. The latent time of neck stretching and head turning of birds were treated
as a control. Neck stretching responses to the distress calls were not significantly different (P = 0.575),
but the alarm calls were significantly different (P < 0.01) and the pre-flight calls were significantly
different (P < 0.01). Head turning responses to the distress calls were not significantly different (P =
0.711), but the alarm calls were significantly different (P < 0.01) and the pre-flight calls were
significantly different (P < 0.01). The results showed that the Common myna responded to the
distress calls of the White-vented myna in the same way as the calls of their own species. There may

have been a bit of a delay when tested with alarm and pre-flight calls (Table 2).

Table 2 Responses of Common myna in each stimuli.

Latent time (s)

Behaviours Sounds Treatment SD Control SD P
(n=10) (n=10)
Distress calls 1.553 0.740 1.373 0.666 0.575

Neck stretching Alarm calls 5.244 4.134 1.285 0.963 0.009
Pre-flight calls 4.694 3.226 1.656 0.810 0.010

Distress calls 3.630 1.393 3.404 1.290 0.711

Head turning Alarm calls 9.843 7.691 2.526 1.035 0.008
Pre-flight calls 8.411 5.621 2.866 2.313 0.010

The latent time of neck stretching and head turning were treated in the White-vented myna
as a control. Neck stretching that was in response to the distress calls was not significantly different
(P = 0.569), the alarm calls was not significantly different (P = 0.493), but the pre-flight calls were
significantly different (P < 0.01). Head turning in response to the distress calls were not significantly
different (P = 0.451), the alarm calls were not significantly different (P = 0.141), but the pre-flight calls
were significantly different (P < 0.01). The results showed that White-vented myna responded to the
distress and alarm calls of the Common myna as same as their own species, but they may have a

bit of a delay while tested with pre-flight calls (Table 3).

Secondary Responses
Both myna species exhibited the same pattern of behaviour when they received the distress
calls. Most of them immediately flew to other areas. The structures of distress calls of both species
had high similarity and the flying responses were similar in both species. In terms of distress call

วารสารสัตว์ป่าเมืองไทย ปีที่ 25 1 พ.ศ. 2561 Journal of Wildlife in Thailand Vol. 25, 2018