Feeding behaviour of herons: 1. Chinese Pond Heron

“The past 4-5 weeks have been very rainy with overcast skies making photography challenging. Took a risk and went into the Tambun foothills where there are many ex-mining pools. Some converted into fish farming. Came across one that was teeming with fish and also with bird life in a feeding frenzy. Although the farmers had covered small sections of the pond with nets, large areas were available for the birds to fish. This pond is 14-15 football fields in size. The birds were sensitive to my presence but the call of the food (fish) was very strong, so I managed to get some views hidden in the end of the pond.

“Estimating a large number of birds amidst a feeding frenzy is not easy. The total volume was in excess of 250 birds. My estimates:
1. Chinese Pond Heron (Ardeola bacchus) > 60
2. Intermediate Egret (Mesophoyx intermedia) > 12
3. Little Egret (Egretta garzetta) > 150
4. Little Heron (Butorides striata) 3-4
5. Purple Heron (Ardea purpurea manilensis) 4-5
6. Grey Heron (Ardea cinerea cinerea) 3
7. Black-crowned Night Heron (Nycticorax nycticorax nycticorax) 2-3

All were engaged in the same activity. As there was no real bank or slope, they had to fly into the pond, dive in to catch the fis (above). I think they were learning from each other but had slightly different modifications of the technique. Of course some of these are well known fishermen but these were fishing ‘in flight’.

“I focused on the Chinese Pond Herons as there are most often seen feeding on dry land, foraging in a park, the edge of water or in a large drain. So it was surprising to see them actually diving for fish. Dr David R Wells (The birds of the Thai-Malay Peninsula, Volume 1, 1999) describes their feeding as largely ‘terrestrial’ but that ‘diet hardly known’.

“I saw countless episodes of the Chinese Pond Herons diving to catch fish over 3-4 hours in 2 days of observations (30/11/2010 and 01/01/2011, more on the first day). I have not seen Chinese Pond Herons do this before and wonder if the farmers had recently introduced new fish fry into this pond that made this event happen.

“I tried handheld videos but there were poor, so some composites and single images posted. When my camera was hidden or I was further away the success rate for catching fish was in excess of 70%. This deteriorated when I came closer or pointed the camera at them.

“The technique used by the Chinese Pond Herons is to wait on some vegetation/bush, some elevation, adjacent to the pond. When spotting a fish they would launch out, flying clumsily just over the surface of the water, trying to hover sometimes with feet trailing in the water (above). Then diving in head first and getting almost completely submerged before emerging with the prize and pushing hard to get free of the water. Then off to the perch to feast. Most perches were out of my view.”

Dato’ Dr Amar-Singh HSS
Tambun Interior, Ipoh, Perak, Malaysia
Ex-mining pool adjacent to limestone hills and secondary growth
December 2010 and January 2011

3 Responses

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.