Cinnamon Bittern / Puchong Bendang (Paddy Field Bittern)

 Bitterns have much shorter necks than other herons and, in the hand (not advised), have have 10 tail feathers whilst other herons have 12.  Bitterns have a reputation as being shy birds, but this is not entirely true.  The IUCN-SCC Heron Specialist Group write somewhat snidely “this is not a well-understood heron, despite being relatively easy to observe”  (HeronConservation » Cinnamon Bittern). 

One the one hand, is true that bitterns are generally difficult to find.  They have excellent cryptic camouflage and when alarmed rely on freezing with an upward pointed bill in a classic bitterning ‘I am one with the reeds’ posture (Dr Amar Singh, bitterning posture ).  Most species live in reed beds, are active at dusk and dawn, and hunt by stealth: “creeping almost cat-like in search of frogs” (Cinnamon bittern - Wikipedia) although insects, snails, crustaceans, and fish are also taken.

Is there a bittern in the photograph below? 

Here is another "Where is the bittern?" photograph

On the other hand, the cinnamon bittern appears unafraid of humans.  In Malaysia, it lives in human altered habitat such as wet rice fields and ex-mining pools where it continues to hunt even when people are working nearby.  Furthermore, during the breeding season, males perch openly and advertise themselves to neighbouring females with a stretch display and a song / call.   

An openly perched male with no females to display to.

The bird below appears to be unhappy with my camera.  I took one photo and left it to rest in the bushes until dusk.  Note the pupil shape and black bars on an otherwise yellow iris.  This is a useful field mark separating cinnamon bitterns from a similar species known as the yellow bittern (puchong kuning).

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Basic facts about this bittern remain unknown; even the total population is a mystery.  Speculation puts the number of cinnamon bitterns worldwide as between 130 thousand to 2 million.  The Malaysian population is said to be in decline.  One (frankly bizarre) explanation I have read is that some Malaysians are hunting and eating this bird. For details, see Dr Amar Singh The Decline of the Cinnamon Bittern Instead, Dr Singh notes that previously, yellow bitterns nested from Penang northwards.  As Yellow bitterns expanded south it appears likely they have out-competed and displaced cinnamon bitterns.