Courtship

I think there is no such difference. Birds use different tonalities to communicate among species based on different stimuli (predators, courtship, resources, etc.). What I think is that what we call whistles are simple signals to alert of one's presence in a specific area, or to point out ...

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I think OP might be interested in female displays of courtship?

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... at different times of the year, maybe one in late summer the other in late winter, so they don't meet. 3.) Behavioural Isolation Due to specific courtship rituals, 2 species might not mate. Some species of birds, although really closely related, cannot mate, because they might have different ...

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... There was also no evidence of hybrid breakdown because hybrid male offspring mating with female offspring of either species did not show abnormal courtship behavior or reduced fertility. The authors conclude that microbial-induced reproductive isolation is already apparent between N. longicornis ...

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As February Beetle said, mating rituals for birds play a large part in courtship but it could just be sexual isolation, i.e. mutual attraction between the sexes of different species is absent. They just don't fancy each other!

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