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

Sightings in November and December 2010

Group of 6 Tufted Ducks (Aythya fuligula)

Migratory ducks tend to arrive on La Palma later in the year than waders. There have been several interesting species on the island this autumn.

A group of 6 Tufted Ducks (Aythya fuligula) appeared in Las Martelas on Nov 25. Within a few days, two of the birds had left the group, possibly to find themselves another pond, or perhaps to continue their southward journey. At the time of writing, 3 birds remain at their original location.

The solitary Garganey (Anas querquedula) above was also photographed in Las Martelas, and is possibly still on the island, although has not been seen recently.

The rather drab Gadwall (Anas strepera) above has been in Las Martelas since Oct 29, but was recently joined by a group of 4 shown below, which arrived on, or just before Dec 12.

Group of 4 Gadwall (Anas strepera)

I assume the above bird is a Eurasian (Anas penelope), rather than an American (A. americana) Wigeon, simply because of the reddish-brown tones on the head and neck. First seen on Nov 25, the bird is still on the island.

However, on Dec 18, two individuals were discovered at different locations. They eventually joined up in the same basin, as can be appreciated in the image below. The second bird to arrive is much greyer in colouring....a female, perhaps?

Even out of its full breeding plumage, the Shoveler (Anas clypeata) is an unmistakable species.

The following male, moulting into winter plumage, was photographed in Las Martelas on Dec 4.

Shoveler (Anas clypeata)

There have also been up to 18 Common Teal (Anas crecca) in Las Martelas in recent weeks, and, at the seawater pools near the airport, the juvenile Bar-tailed Godwit (Limosa lapponica) was discovered on Nov 18, later to be joined by a second bird. Both are still present at the time of writing.

My apologies to all followers of this blog for the lack of new posts in recent weeks. I am presently experiencing serious technical problems with my Internet connection at home, and am having to use other people's computers and Cyber Centres. Hopefully the problems will be solved by early 2011.

A third American Golden Plover!

American Golden Plover (Pluvialis dominica)

The juvenile American Golden Plover (Pluvialis dominica) shown here is the third example of this neartic vagrant I have observed on La Palma this autumn. The two previous birds were both discovered in freshwater irrigation basins in Las Martelas, and one of them is still to be found there at the time of writing.

This third example, however, was seen feeding at the seawater pools opposite the airport, on the east coast of the island, on Nov 6. The relevant plumage details can be clearly appreciated in this series of images, and identification and distribution of this long-distance migrant have been briefly covered in previous posts.
It is perhaps interesting to reflect that P. dominica was not separated from P. fulva until relatively recent times. Present-day populations of the former are estimated at 10,000-50,000 individuals, despite heavy hunting in the past. The post-breeding migration route is typically an ellipse, in which the outward journey from the arctic and subarctic tundra of North America initially follows the east coast of Canada southwards, crosses the Caribbean, and eventually reaches wintering quarters in Argentina, with the return journey being routed further to the west.
Most remarkably, it appears that the leg from Canada to South America is covered in a single non-stop flight, which, in fair weather, is estimated to take 37 hours. Hardly surprising then, that vagrants turn up in Europe, and other parts of the world, fairly frequently!

Up to 2003, only 28 records of dominica in Spain had been accepted by the Spanish Rarities Committee: 12 in the Canary Islands, and the remaining 16 on the mainland.

The above information has been taken from Aves Raras de España (Eduardo de Juana, Lynx Editions, 2006), a catalogue of bird species of occasional occurrence in Spain. The book includes a table of all records accepted by the Spanish Rarities Committee up to the year 2003.

A second American Golden Plover

American Golden Plover (Pluvialis dominica)

On Saturday 23 October, I discovered this juvenile American Golden Plover (Pluvialis dominica) in Las Martelas, and the bird was still there today, Oct 25, when these three photographs were taken.

The second example of this North American migrant to appear on La Palma so far this season, two birds have also been recorded on Lanzarote in recent weeks: see appropriate links in Canary Islands Bird News for more details.

Plumage details of the previously-detected adult bird were harder to appreciate than in the present case: in the above photograph, there's no mistaking the four primaries projecting beyond the tertials, with two extending beyond the tail end.

This species "breeds in North American Arctic and subarctic tundra, and migrates south through interior North America, or via Hudson Bay, to reach the coast around New England, then over the Atlantic to South America, with the non-breeding season being spent in northern Argentina and Uruguay" (Shorebirds of the Northern Hemisphere, R. Chandler, 2009).

Presumably it is during that "over the Atlantic to South America" part of the migration route when certain individuals go astray...especially in autumns as stormy as the present one.

The Spanish Rarities Committee is receiving an unusually high number of records for assessment this year, including the country's first Bobolink (Dolichonyx oryzivorus), a transatlantic passerine currently located on Lanzarote.

Another North American vagrant at the saltpans

White-rumped Sandpiper (Calidris fuscicollis)

The saltpans at Fuencaliente recently attracted yet another North American migrant: following the Semi-palmated (Calidris pusilla) and Buff-breasted Sandpiper (Tryngites subruficollis) of two previous posts, on the evening of Oct 21 I discovered a solitary White-rumped Sandpiper (Calidris fuscicollis), feeding together with 3 Sanderlings (Calidris alba).

The island of La Palma actually holds the Spanish record for the largest single influx of this particular Nearctic wader, with 6 birds in Las Martelas on Oct 10 2005, 9 individuals at the Fuencaliente saltpans, and 4 at the seawater pools near the airport on the same date! (Ardeola, 54/2)

Note the wing tips projecting beyond the tail

Body size is somewhat smaller than the two Sanderlings shown above, and much more elongated in appearance.

The pale brown colouring on the underside of the bill, and the white rump which gives the species its name, can be clearly appreciated above and below, respectively.

This record will be submitted to the Spanish Rarities Committee in due course.

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Autumn 2010 sightings

Tringa glareola and Calidris alpina

The Wood Sandpiper (Tringa glareola), shown above accompanied by a Dunlin (Calidris alpina), has been sighted several times in Las Martelas in recent weeks; in fact, there might actually be two birds in the area at present. This passage migrant is a much less frequent visitor than both the Green Sandpiper (Tringa ochropus) and the Common Sandpiper (Actitis hypoleucos).

Northern Wheatear (Oenanthe oenanthe)

Solitary examples of Northern Wheatear (Oenanthe oenanthe) are recorded on the island of La Palma almost every year, and are considered "regular passage migrants" by T. Clarke (2006, "Birds of the Atlantic Islands").

Glossy Ibis (Plegadis falcinellus)

The Glossy Ibis (Plegadis falcinellus) featured in two previous posts, was still on the island on Oct 12, but had moved from the Tazacorte area to a group of irrigation basins in Las Martelas, where the above photograph was taken.

Common Snipe (Gallinago gallinago)

The Common Snipe (Gallinago gallinago) often winters in small groups on La Palma. So far this year numbers have been low, since hardly any suitable habitat is available for a species which forages in basins with muddy or soft sandy bottoms. The bird's diagonal probing, rather than vertical stitching, can be appreciated in the photo above.

Above: two images of the juvenile Buff-breasted Sandpiper (Tryngites subruficollis), which was still at the Fuencaliente saltpans on Oct 3.

Common Greenshank (Tringa nebularia), also at the saltpans on the same date

2 North American vagrants at the saltpans

View of the saltpans on the windswept southern tip of the island

The saltpans at Fuencaliente attracted two rare North American vagrants in September: a Semipalmated Sandpiper (Calidris pusilla) on 24/09, and a Buff-breasted Sandpiper (Tryngites subruficollis), first detected on 29/09 but still present at the same location on 03/10.

The Semipalmated Sandpiper "breeds in the arctic and subartic tundra from far-eastern Siberia, Alaska to Baffin Island and Labrador, and winters in Pacific Central America, West Indies and northern and central South America. It is a vagrant to Galápagos, the Azores, and Europe east to Hungary" (Shorebirds of the Northern Hemisphere, R. Chandler, 2009).

Curlew Sandpiper and Semipalmated Sandpiper (C. ferruginea and C. pusilla)

Dunlin and Semipalmated Sandpiper (C. alpina and C. Pusilla)

Apart from the short, straight, blunt-tipped bill, and the very short primary projection beyond the tertials, the critical identification feature, which gives the species its name, can be seen in the next two images - the partially-webbed toes:

Further images of the same bird, found feeding in a small mixed flock of Curlew Sandpiper (C. ferruginea), Dunlin (C. alpina) and Sanderling (C. alba):


There have been 14 officially-accepted records of this species in Spain to date, mostly in the autumn, including 3 from the Canary Islands. Two of the Canary Island sightings are from Tenerife (Oct 1996 and May 1997) and the third is from Lanzarote (Nov 1998). The present bird could therefore be the first for La Palma, the 4th at regional level and the 15th for Spain as a whole, pending homologation by the Spanish Rarities Committee.

The second nearctic vagrant discovered at the saltpans is shown below. This juvenile Buff-breasted Sandpiper (Tryngites subruficollis) is also a long way from home! The species breeds "on well-drained grassy tundra, locally in north-east Siberia, northern Alaska and northern Canada east to King William Island" and spends the non-breeding season "on sparsely vegetated wet grasslands primarily in Argentina" (Shorebirds of the Northern Hemisphere, R. Chandler, 2009).

It is a much commoner visitor on this side of the Atlantic than the previous species, with 40 records from Spain, including 7 from the Canaries. This sighting is also the first for La Palma and will be submitted to the Spanish Rarities Committee in due course.

Above and below, Buff-breasted Sandpiper (Tryngites subruficollis)

Further information regarding the status of the above species can be found on avescanarias.blogspot.com, the Canary Islands Bird News blog.