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Night herons in the day!

If you thought night herons are nocturnal creatures, think again

OPPORTUNISTIC FEEDING A juvenile night heron with its prey

Birds don't read field guides. Even if they do, they don't follow them to the letter. On night herons, field guides say, "They are essentially crepuscular/ nocturnal. They forage for food during the matutinal (predawn) and vespertinie (dusk) hours." These field guides add that during the breeding season, night herons are active round the clock — the day's workload includes collecting nest material, waging battles against other wetland birds that eye their nest material, courting and mating and, of course, feeding themselves.

Feeding habits

Do night herons turn diurnal only when Nature casts them in the drama of regeneration? Would a juvenile night heron pass up an opportunity to swallow a fish when it is offered on a platter?

Naturalists familiar with the behaviour of the bird maintain that night herons of all ages and sizes like to swoop down on a fish even during bright, daylight conditions. For want of evidence, this contention has been given the respect any unsubstantiated theory commands. Now, bird photographer P. Ramanan has clicked a picture that supports this observation.

During one of his visits to the Vedanthangal Bird Sanctuary in March this year, he photographed a juvenile night heron capturing fish at about 1 p.m. in the lake, which was shimmering in the bright sunlight.

Ramanan says, "The juvenile seemed to be striking a pose holding the struggling fish in its bill. Other wetland birds were fishing close to this young night heron. A forest guard at the sanctuary disputed my identification of the bird as a juvenile night heron and insisted that it was only a diurnal feeding pond heron. People not familiar with all the phases in the life cycle of a night heron mistake the juvenile night heron for a pond heron. The adult and juvenile forms of the night heron are strikingly different." And the juvenile night heron bears a superficial resemblance to the pond heron.

P. Sivaramamurthy, Estate Manager, The Simpson Estate (Sembium), who has watched night herons at close quarters, says, "There is nothing unique about crepuscular/ nocturnal birds helping themselves to food when they see it spread out invitingly sometime during the day — like fish trapped in isolated, shallow pools or surfacing in large numbers. We call it opportunistic feeding — the sight of other birds feeding on easily available prey often acts as a cue to trigger diurnal feeding behaviour."

Black and yellow bitterns, which are also slotted in the crepuscular/ nocturnal category, hunt during the day when they sense an opportunity to do so. The nocturnal short-eared owl chooses to be diurnal when assured of safety. On some of the Galapagos Islands, this owl is out the whole day. Because these spits of land are free of its nemesis — the buzzard.

PRINCE FREDERICK

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