|proudly sponsored by Oryx||
Birds in Spain
Images and text by Juan Antonio Lorenzo Gutiérrez *
* Delegación Territorial de Canarias de SEO/BirdLife. Avenida Trinidad Nº 55, Edificio Anchieta, puerta 121, 38206 – La Laguna, Tenerife, islas Canarias. Tlf.- fax 922 252129, e-mail: email@example.com
On 23.11.2001 a bird which apparently seemed a member of Rallidae family was found at Parque García Sanabria, the main urban park of Santa Cruz de Tenerife town, in Tenerife island, Canaries. It was found alive but in extremely bad condition in the middle of the vegetation of a small pond of the park. It was then collected by members of the Wildlife Recovery Centre of the Tenerife authorities (Centro de Recuperación de Fauna Silvestre del Cabildo de Tenerife). Sadly, however, the bird could not be recovered and it died on 24.11.2001 and its corpse was frozen. After an initial study of the bird by Juan Hernández-Abad and Carmen Méndez, both from the recovery centre, it was identified as an odd Rail some of whose features did not fit Eurasian Rail Rallus aquaticus, the rail which can be expected to arrive during its migrations to the Canary Islands.
As every time a vagrant or a scarce migrant appears in the recovery centre, the people from the Centro called Juan Antonio Lorenzo, member of the Spanish Rarities Committee (CR/SEO) to give a look to the corpse. Besides photographs and biometrics, they altogether took a brief description of the corpse and the final conclusion was that the bird belonged to the African species Crex egregia.
Although the general pattern of the bird recalls that of Eurasian Rail Rallus aquaticus, there are noteworthy and obvious differences that exclude the latter species. Those include length and colour of the bill and facial pattern. Distinction from Corncrake Crex crex is also straightforward. The enclosed photos are very clear and show all main identification diagnostic characters that pointed towards the proposed species.
Biometrics (in mm)
Bill to feathers 122
Bill to skull 125,5
Central finger 36-35
Besides head and bill details, both the pattern of vent and lower breast with black and white markings that include undertail coverts area as well; and the brownish tinge to the undertail coverts are typical of the species. Underwing coverts are also indicative of the species.
The obtained biometrics are within the ranges given by Taylor & Van Perlo (1998) and Urban et al (1986). However, the bird measurements do not allow its sexing given the overlap in male and female values.
Plumage examination allowed us to determine the bird as an adult. Besides, there are strong possibilities that the crake was a male on the basis of plumage pattern although expert confirmation would be interesting in this case. Basically, all feathers were in pristine condition and there was no sign of moult. Taylor & van Perlo (1998) mention the species undertaking a complete post-breeding moult just prior to migration.
As Martin & Lorenzo (2001) state, the Canary Islands constitute a strategic hotspot for African vagrants. Some of the recorded species come from northern desert habitats such as Bar-tailed Desert Lark Ammomanes cincturus, Hoopoe Lark Alaemon alaudipes, Desert Wheatear Oenanthe deserti and Desert Warbler Sylvia nana. Others come from the wetlands south of Sahara, being wildfowl dispersing due to rainfall or draught periods. These species include Allen’s Gallinule Porphyrula alleni and Dwarf Bittern (Ardeirallus [=Ixobrychus] sturmii).
All these African species have already accepted records by the Spanish Rarities Committee (CR/SEO). Amongst the mentioned species it is worth noting the pattern of Allen’s Gallinule with nine records in the islands, most of them of 1st winters and almost all between November and March (Martin & Lorenzo 2001).
The arrival of African origin depressions that reach the Canaries from Mauritania, Sahara and Morocco coasts are behind the presence of many of these vagrants as well as some European migrants given winds coincide with their migration periods. Strong winds and storms from N and NE origin preceded the dates in which the African Corncrake was discovered in Tenerife, hence these being quite unlikely to be relationed with the Crex arrival. Therefore, it is possible that the bird had arrived before the finding dates, associated to other storms such as those of early November 2001 that even involved the arrival of Saharan dust to the islands.
The bibliography states that this species has a good vagrancy potential being a good migrant but having a complex pattern of movements along its distribution area (Urban et al 1986, Avery et al 1988, Taylor & Van Perlo, 1998, Del Hoyo et al 1996). According to these references, the species is present from June to September in the African countries close to the Canary Islands: Mauritania (probable vagrant in the SE), Senegal (only 3 records, one north of Dakar), the Gambia (scarce or rare resident) and Guinea as well. There is a migration pattern towards southern parts of its range associated with rainfall periods. Besides, migrations are nocturnal and there are a number of migrant birds having been attracted by lights or by towns, having been found in urban areas, such as the Tenerife case. Other island records off Africa are those of birds recorded at Santo Tomé and Bioko islands.
From now on a good advice for both local and visiting birders is to pay a little more attention to any rail in these islands because any species can be expected!
In the last Spanish RC meeting (February 2002), the CR/SEO examined the record and accepted it without any problem. Hence, it becomes the 1st record for Spain and also the Western Palearctic.
To know which species need to be submitted to the Spanish RC you can download a complete list from the files section of this website.
All photos depicting the corpse of the African Corncrake in Tenerife, Canary Islands. All photos by J.A.Lorenzo & Cabildo Insular Tenerife.
To the people of the Centro de Recuperación de Fauna Silvestre del Cabildo de Tenerife and particularly to Cármen Méndez and Juan Hernández-Abad without whom this record would have been lost. The author wants to thank Ricard Gutiérrez for his interest in making public the record.
Thanks to Juan Antonio Lorenzo for sending the photos for its publication in the web site and circulation amongst the CR/SEO of which he is also an active member. Gracias a Toño Lorenzo por enviar las fotos para su publicación en la web y circulación en el CR/SEO del cual él es también un miembro activo. Gràcies al Toño Lorenzo per les fotos per a la web i el CR/SEO del qual és també n'és membre actiu.
African Corncrake Crex egregia in Tenerife, Canary Islands, 1st for the Western Palearctic
Spanish version of this page here
Designed to be seen in 800x600
resolution with Java enabled browsers.