Here's a neat observation on #iNaturalistNZ. iNat user "catchwords" took an excellent set of photos of a shining cuckoo, pīpīwharauroa, in the Coromandel, NZ, eating caterpillars of magpie moths, mōkarakara.

No other bird in NZ eats these caterpillars, as the caterpillars sequester the poisons from the groundsel plants they eat, similar to what monarchs do with milkweeds. The stiff hairs on the caterpillars are also known to pierce the lining of bird gizzards.

Shining cuckoos typically squeeze out the innards of the caterpillars and eat those and then discard the skin.

The birds can also eat cinnabar moth caterpillars in NZ, which were introduced as a biocontrol agent for ragwort. Like magpie moths, cinnabar moths sequester the toxic alkaloids in the ragwort they feed on. Shining cuckoos don't care.

Many birds in the family Cuculidae, the true cuckoos and koels, are known to eat hairy and toxic caterpillars that other birds avoid.

https://inaturalist.nz/observations/253969377

#birds #iNaturalist #Lepidoptera #caterpillars #EcologicalInteractions #nz #ecology #nature #cuckoos