Having established the snake's position, I think we should once again check the calendar for the months of the Easter Islanders. At spring equinox we ought to find some trace of kava.

But first I happen to notice something else:

"Kena = A sea bird, with a white breast and black wings, considered a symbol of good luck and noble attitudes."

"Moa tu'a ivi raá, 'sun-back chicken': chicken with a yellow back which shines in the sun."

The kena bird is white in front (mua) and black on the back (muri), whereas moa tu'a ivi raá has a golden back (and presumably a front of more ordinary appearance). These birds are opposites.

It does not seem to be a coincidence that kena is located in the 1st month (Anakena) and this golden moa in the 7th month (Tua haro). Althought, of course, there is nothing in the name Tua haro to make one think about moa tu'a ivi raá, that is just an example of the use of the word tu'a (fetched from internet: http://www.rongorongo.org/vanaga/).

At winter solstice (Anakena) the white season is in front (in the future) and at summer solstice (Tua haro) the golden season of growing has just passed away.