domingo, 16 de noviembre de 2014

Grackles (Quiscalus) in the Iberian peninsula

Quiscalus mexicanus, Mexico, 31.8.2007 © Ricard Gutiérrez

Grackles (genus Quiscalus) are birds from Icteridae family, typical of Neotropical region, but also present in the Holartic, including USA coast. Typical 'resort' birds known by many as those 'black' birds frequenting the tables of hotels in the Caribbean or Mexican coasts trying to steal food from customer's breakfast or lunch. 

Not a typical long-distance migrant group, they are believed to be quite intelligent, in a rather Corvidae mood, so despite they cannot be considered as true vagrants to the Palearctic according to the uncapability of crossing by themselves the Atlantic, it is true that they (presumably) board on ships to do the crossing. And not only one species but, at least, two having been recorded in Gibraltar and mainland Spain. 

E-listed in Europe due to the 'current rules', a review of the treatment of what A listing means regarding 'clever' birds such as Corvidae or these Grackles, could turn up in having these species included in the Spanish and European lists.  Hence, a review of recent known reports, after at least two  birds this 2014 fall seems of some interest.



  1. Quiscalus mexicanus. Cadaqués, Girona, (42.288530N 3.278058E) 25 October 2014 


A  bird was photographed at Cadaqués, Girona on 25.10.2014. It had been in the area at least for 2-3 days according to local birdwatchers (Ponç Feliu in litt). It was seen many times trying to feed on the terrace of La Boia bar by the Cadaqués beach. Salvador Oliu photographed the bird and the images are enclosed below. 






Quiscalus mexicanus. El Port de la Selva, Girona, (42.339793N 3.203845E) 31 October 2014 

Presumably the same bird despite what some of the enclosed photos may suggest, was seen at El Port de la Selva, Girona, also in the Creus cape area, six days later (8,21 km minimum distance at 132,72º). Jesús Aparicio saw the bird and called Ponç Feliu who was nearby and went to the area to photograph the bird (see below).


 



2. Quiscalus mexicanus. Europa point, Gibraltar, (36.109303N 5.345679W) 4 November 2014


A bird was seen at Europa point, Gibraltar, on 4.11.2014 (Paul Rocca). It was properly identified on 12.11.2014 (Clive Finlayson, Stewart Finlayson, Paul Rocca, Charlie Perez, Keith Bensusan, Rhian Guillem/GONHS) when photographed too (Steward Finlayson, see below). More details in the GONHS website here. Also seen by Spanish observer Álex Colorado in the evening.







3. Quiscalus quiscula . Gibraltar, (36.132001N 5.351692W aprox) Unknown, 2010

The November 2014 sighting has made available another record, in this case of a presumed Common Grackle Q.quiscula also at Gibraltar (above coordinates only indicative) back in 2010 by Jonathan Perera (see photo below).




Discussion

Distribution of the Great-tailed (see below) and Common Grackles match the origin of well-established maritime traffic routes from Mexico Gulf to the Mediterranean. 

Quiscalus mexicanus distribution (Source: wikipedia)
Traffic statistics from the Barcelona harbour, Catalonia in September 2014 show how a part (not the most important though) of the ships coming through the Straits and into the NW coast of Iberia come from the Gulf of Mexico. 

Birds such as this one, or the recent Mourning Dove Zenaida macroura (one or two birds) seen during October-November 2014 near the Barcelona harbour -not fully discarded as an escape, but from where?- could have this origin.  






Traffic statistics of Barcelona harbour as from September 2014 (taken from Port de Barcelona stats)
 
© Christoph Weinrich, 7.11.2014 www.rarebirdspain.net 
 

The small proportion of ships coming from America to this part of the country could explain the scarcity of reports of presumed ship-assisted birds which interestingly match a fall (autumn) pattern. Besides, birds coming on board of a ship tend to flush towards land once they see it (given they are in good condition) what would explain the presence of birds in Gibraltar but the Cadaqués-Port de la Selva area too: both villages are located in the NE extreme cape of Iberia, the Creus cape, which has to be avoided by maritime traffic heading to Lion gulf. Perhaps a ship sailing near the cape towards France or Italy was the origin of that (presumably one) bird.

Given the listing rules applying to ship-assistance are modified for clever birds such as crows and ravens, the occurrence of grackles in Europe could account for the same treatment. For the moment, collecting their records might be a good idea.


Acknowledgements. Charles Pérez/GONHS and Ponç Feliu for providing information and photos on these interesting sightings.