do you breathe like a crow or not

​ok, so in the Rudra Yamala Tantra it recommends we breathe like crows...what exactly does that mean?
as we know, mammals and birds DO NOT breath the same...
This graphic is worth exploring to see the difference. 
Here's a translation of the verse.

“When the stage is achieved that enough food has been taken for himself, at that instant the stomach should not be further filled and vital breath should be taken in just as a crow does through its beak. In other words, one must take in breath by doing ‘kumbhaka.” — Rudrayamala Tantra 23.12

Here's the original.
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yāvatkālaṃ kṣayaṃ yāti nijabhakṣaṇanirṇayam | 
tatkālaṃ vāyunāpūrya nodaraṃ kākacañcubhiḥ ||