Annual Ardeidae Census

Fish-farm off the west coast (Tijarafe)

January 15 was the target date for the annual census of Ardeidae, a nationwide effort promoted by SEO/Birdlife to quantify members of the heron family over-wintering in Spain. Figures for the island of La Palma are still pending, but should be available by the end of this month.

To carry out the survey, observers are required to station themselves at known roost sites before sunset, and count members of the relevant species as they fly in to spend the night. In the case of La Palma, only two species of Ardeidae are involved: the Grey Heron (Ardea cinerea) and the Little Egret (Egretta garzetta).

One of the locations which previously attracted large numbers of this latter species was the fish-farm off the west coast of the island, shown above: over 70 Little Egrets were regularly seen flying to and from the cages anchored offshore. However, during a recent visit to the site, I counted only a dozen birds or so, plus a handful of Grey Herons. The two images below, taken in March 2008, give an idea of the former abundance.

Flock of Little Egret heading for the cliffs

Large numbers of mainly Little Egrets opposite the fish-farm

It is unknown whether such impressive numbers of Little Egret continue to feed and/or roost on the west coast, but some birds can still be observed flying out of the Angustias Ravine in the evening, and then heading in a northerly direction towards the cliffs of Tijarafe. Further field-work is obviously required to ascertain present-day numbers.

During recent prospections a new communal roost has come to light, in rather surprising surroundings. A few days ago I counted 47 Little Egret and 1 Cattle Egret (Bubulcus ibis) flying into the banana plantations shown below late in the evening.

In the centre of the following image is an irrigation basin, hidden from view between the two parallel breeze-block walls. The Egrets tend to arrive from 18:30 onwards, often perching on one or other of the walls, before finally settling down for the night in the tops of the banana plants!

Recently-discovered Little Egret roost

The main roost itself is located in some of the least accessible banana plantations in the whole area, on land which is strictly private property and well walled-off and gated. However, some of the peripheral roosting sites can be reached without trespassing, and the two photos below were taken from a nearby irrigation canal.

Appearance of some of the banana plants used by Little Egret as roosting sites