Semipalmated Plover: the story so far...

Followers of this blog will be familiar with the Semipalmated Plover (Charadrius semipalmatus) which has now been at the airport pools on La Palma for about one month. Just to recap, here is a brief summary of the story so far...

Oct 4: The bird was discovered and correctly identified by Tom Brereton and Marcus John, about 45 minutes before they were due to catch their flight back to the UK. They observed the bird through a telescope, but failed to get satisfactory photographs. That evening, I received the following, extremely concise email from Tom: "Semipalmated Plover airport pools".

Oct 5: Not entirely convinced that the alert wasn't some kind of practical joke, I headed for the site with my photographic gear, and within minutes of arrival had found the mega-rarity. The first photos were posted on my website the same day.

Oct 8: I returned to the airport pools and posted another set of pictures on "La Palma Birds", including a couple of views of the not very scenic location and surroundings.

Oct 18: The bird was observed at the same spot by a visiting birder, Javier Orrit (pers. com.)

Oct 19: An early visit with good light conditions and absence of disturbances produced my best pictures of the bird so far. The various differences between semipalmatus and hiaticula were now evident, thanks to the convenient proximity of the latter.

Oct 23: Javier Orrit and myself observed the bird with a telescope.

Oct 27: I checked to confirm that the bird was still present.

Oct 29:  Another visiting birder, John Perry, informed me of his personal sighting.

Oct 31: Together with two visitng birders, Juan Sagardía and José Portillo, the bird was observed again. Juan also filmed, recorded, and photographed it. (José Portillo is presently the presumed leader of the Spanish version of "The Big Year" - an unofficial twitching race to see the largest number of bird species in 2013 within Spain, including the Canaries, Balearics, Ceuta and Melilla. With the total number of Spanish species standing at 569, and another two months to go, José Portillo is already nearing the 400-mark. The Semipalmated Plover at the airport pools on La Palma has been another valuable addition to his list. More details of the competition and an interview with José Portillo at http://rbsbt.blogspot.com.es/2013/07/el-gran-ano-2013-medio-camino.html in Spanish).

The bird confidently associates with a small flock of Ringed Plover, a species which regularly winters on La Palma...so there is a very good chance that the semipalmatus will stay with them.

Nov 9: 14h The bird was still present at the airport pools.

Nov 10: Observed by a visiting birder,  Óscar Llama (pers. com.).

Nov 15: The bird was still present at the same site.

Nov 19: It was seen by Clemente Usategui at the same location (pers. com).

Nov 22: I observed the bird at the same spot.

Nov 24 & 25: Still present (Sergi Fernández)

Nov 27: Still present at same site.

Semipalmated Plover III

 Semipalmated Plover (Charadrius semipalmatus)

The Semipalmated Plover (Charadrius semipalmatus), featured in the previous post, was observed yesterday Oct 18 at the same location by Javier Orrit, so I returned to the site this morning to take a few more photographs of the bird.

The close proximity of 3-4 Ringed Plover (C. hiaticula) for comparison facilitates appreciation of the differences between the two species. C. palmatus has paler, thinner legs, a shorter, more conical bill, an overall "daintier" build, and a thin orbital ring absent in hiaticula.

This morning I was less concerned with photographing the bird's feet, since my earlier photos show the webbed toes well, but above is another clear view of the webbing between the two inner toes.

When not foraging at the edges of the tidal pools, this Semipalmated Plover conceals itself amongst stones in the gravelly areas nearby, together with small groups of Ringed Plover.

A number of the previously-mentioned differences between semipalmatus and hiaticula can be seen in the picture below:

Charadrius semipalmatus and C. hiaticula

Semipalmated Plover II

 The "airport pools" looking north, with the airport access road visible on the left, and  Santa Cruz de La Palma in the distance.

 The "pools", locally known as Las Maretas, are actually disused gravel pits which provided materials for the construction of the airport. 

Despite the unpicturesque surroundings, the location is very popular with all kinds of people, especially at weekends and on sunny afternoons: dog-walkers, joggers, bait-gatherers and anglers, families with young children, and cars and even caravans can all be found here. How the Semipalmated Plover (Charadrius semipalmatus) will cope with all this potential disturbance remains to be seen, but the bird was still foraging at the site this morning (Oct 8), together with two or three Ringed Plover (C. hiaticula).

Note the difference in size between Semipalmated (foreground) and Common Ringed in the above image. The obvious webbing between the two inner toes, a diagnostic identification feature of semipalmatus, can also be appreciated.

The bird was in a less-favourable spot for photography this morning, so I have been unable to improve on the first photos taken on Oct 5. The verdict of several experienced observers coincide in that this specimen is not a juvenile, as previously assumed,  but an adult.

This record of Charadrius semipalmatus, if accepted by the Spanish Rarities Committee, will be the fifth for Spain, and the first for the Canary Islands. It seems likely that such low numbers of sightings do not reflect the real numbers of semipalmatus arriving in the country, but can be attributed to the fact that this species is very easily overlooked.

Semipalmated Plover

 Semipalmated Plover (Charadrius semipalmatus)

Congratulations to Tom Brereton and Marcus John of Naturetrek for finding the mega-rarity featured in the present post: a juvenile Semipalmated Plover (Charadrius semipalmatus), discovered at the seawater pools next to the island's airport. I was tipped off by Tom yesterday evening (Oct 4) and managed to photograph the bird this morning.

There are presently about four Ringed Plovers (Charadrius hiaticula) at the same location, but the Semipalmated was not difficult to find. Note the very thin, pale orbital ring, and of course, the distinct webs between both outer and inner toes.

The photograph above, and the heavily-cropped version below show the webbed toes clearly.

Other identification features include the relatively narrow, dark breast band, unbroken in the centre, and the overall smaller size of this bird, compared to the nearby Ringed Plovers present at the same site.

I will submit this sighting to the Spanish Rarities Committee in due course, as second observer of this North American vagrant.

Juvenile Semipalmated Plover (Charadrius semipalmatus), discovered by Marcus John and Tom Brereton during a recent trip to La Palma
(All photographs by R. Burton)

September 2013 summary

 Northern Wheatear (Oenanthe oenanthe)

The highlight of recent weeks was undoubtedly the juvenile Citrine Wagtail (Motacilla citreola), found in an almost-empty irrigation pond in Las Martelas (see previous post). Otherwise, it was a pretty quiet September for migrants, with most of the main ponds in Las Martelas dried out and therefore providing hardly any suitable habitat for birds. Only a few common waders turned up in the first half of the month.

However, on Sep 29, on the road to the summit of the island at almost 2,300m altitude, I spotted the Northern Wheatear (Oenanthe oenanthe) shown in the two images above. The precise location was at Km 31, just below the peak known as Pico de la Cruz.

 Northern Wheatear (Oenanthe oenanthe)

There have been several sightings of this species on La Palma in recent years, most of them at much lower elevations. The bird shown in the  image above, and in the next two pictures, was discovered at what might be described as a "classic" location for ground foragers: Llano de las Cuevas in the high part of El Paso, at around 900m above sea-level. The pictures were taken on Oct 2.

I am hoping a Desert Wheatear (O. deserti 12 records on the Canaries), or an Isabelline Wheatear (O. isabellina only one record on the Canaries) will turn up on the island one of these days, but the very long primary projection shown below, reaching almost to the tip of the tail, discounts both of these rarer species.

At the beginning of the month, when several juvenile shorebirds and a few wagtails were foraging in one of the irrigation tanks in Las Martelas, a surprise visitor spent several minutes perched on the edge of the pond...perhaps scrutinising the larder, prior to sampling some of the recently-arrived, overseas delicacies. Sparrowhawks are not often seen in such urban surroundings on La Palma...

I assume the bird below is a juvenile of the  resident sub-species granti.

Sparrowhawk (Accipiter nisus ssp. granti)

Citrine Wagtail

 Curlew Sandpiper (Calidris ferruginea) with first winter Citrine Wagtail (Motacilla citreola)

The post-breeding migration season is already underway, and along with the regular shorebirds, what I take to be a first winter Citrine Wagtail (Motacilla citreola) has turned up in a partly-empty irrigation pond in Las Martelas (Los Llanos de Aridane). Seen for the first time on Sep 8, the bird was still present this evening, Sep 10.

The recently-published "Rare Birds of the Canary Islands" (Eduardo García-del-Rey & Francisco Javier García Vargas, Lynx Edicions, June 2013), gives a total of 6 records of Motacilla citreola on the Canaries: El Hierro 1, Tenerife 1, Fuerteventura 1, and Lanzarote 3. However, in early September this year, two more citrines were observed at the Tias golfcourse on the island of Lanzarote.

Despite the poor quality of the present photographs, several key identification features can be appreciated: the broad white wing bars, the pale eye-surround, the black legs, and the all black bill. Plumage on the upperparts is greyish, with no hint of olive-brown, as in immature Yellow Wagtail (M. flava).

As further evidence, this bird shows no hint of a black collar, as in the White Wagtail (M. alba), and also lacks yellow tones on the undertail-coverts, as in immature Yellow Wagtail (M. flava).

Any comments regarding identification of this bird would be appreciated: please email me at grajaland@gmail.com.

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

Other migrants currently found in Las Martelas include small numbers of:
Curlew Sandpiper (Calidris ferruginea), Green Sandpiper (Tringa ochropus), Common Sandpiper (Actitis hypoleucos), Greenshank (Tringa nebularia), and Common Snipe (Gallinago gallinago).

Elsewhere on the island, I have seen solitary Dunlin (Calidris alpina), Sanderling (Calidris alba), Greenshank (Tringa nebularia ), and Curlew Sandpiper (Calidris ferruginea) at the Fuencaliente saltpans, and two Ringed Plover (Charadrius hiaticula) plus one Whimbrel (Numenius phaeopus) and a solitary Common Sandpiper (Actitis hypoleucos)  at the seawater pools near the airport.

Gull-billed Tern

 Gull-billed Tern (Gelochelidon nilotica)

A welcome observation after a quiet spell in Las Martelas, this Gull-billed Tern (Gelochelidon nilotica) was discovered on the evening of June 21. I managed to get a couple of acceptable pictures on that occasion, but have posted the slightly better quality ones taken today, June 22.

This is my second record of this species on La Palma, the first being in September 2011 (see Sep 12 2011 post). However, both currently available field guides to the birds of the Atlantic Islands/Macaronesia, by Tony Clarke and Eduardo García-del-Rey, refer to the Gull-billed Tern as a "passage migrant with records from all main islands except La Palma".

Back in September 2009, I also saw 3 Whiskered Terns (Chilodonias hybrida) in the same area (Las Martelas, Los Llanos de Aridane).

What a spectacular bird to observe, as it glided and leisurely circled above this artificial wetland! The wings gave the impression of being much longer than the 76-86 cm quoted in the guides. The dark trailing edge on the outer primaries is clearly visible in the three photos above, and also the short, thick, all-black bill.

The tern was attempting to pluck insects from the surface and edges of some of the irrigation ponds, and only perched briefly once, on top of a plastic greenhouse, some distance from where I was standing. The next two shots, unfortunately rather blurred, illustrate the foraging techniques:

Above, the bird is seen scouting the banks of an irrigation pond, and below, a captured prey item, probably a recently-emerged dragonfly, is visible.