Nutcracker
Stop Brexit!
:t:Well spotted! obviously southeastern France!
Thanks Nutcracker
B
Just when I was hoping they might be crossing the Channel soon . . . :-O
:t:Well spotted! obviously southeastern France!
Thanks Nutcracker
B
Thanks John. So this Torrevieja population looks as if it is likely to be introduced, but the local Iberian Magpie. How long does one normally wait to see the population establish itself before it is deemed sustainable? The lack of suitable habitat could well be a factor in this attempt to establish the species that far east.
Interestingly, your own article has a map that shows the eastern seaboard as too dry. Time will tell ultimately, if they make it.
In your opinion, one I respect, do you feel I should mention this population? Maybe something like the following would suffice:
This species is thought to have been introduced to Torrevieja in around 2014, on the eastern side of Spain about 200 km away from existing populations. Due to a lack of suitable habitat and the prevailing arid climate, time will ultimately tell if the attempt to populate this area has been a success.
And for movement, I suggest something like:
Evidence from bird ringing projects suggest that although this species is usually sedentary, in the Sierra de Gredos, in central Spain, and at the Pajares pass in northwest Spain it appears to ocasionally make altitudinal migrations to lower valleys to avoid bad weather in the winter. There are several records of movement in southeastern France, the most recent in the Camargue in December 2005. In general, occurences of individuals or small groups making such journeys are rare.
I found this criteria for AOU
"Species that have been introduced by humans, either deliberately or accidentally, are considered to be established if there are persistent records of or at least ten years and satisfactory evidence that they are maintaining a reasonably stable or increasing population throughs duccessfurle production"
Gosh, you respect my opinion. That's very kind I don't always do that myself!
I'm not sure whether there's an 'official' period for how long it takes an introduced species to be regarded as having established a self-sustaining population. I know that there are cases of species thriving and doing well for decades but then suddenly disappearing so I guess there's no clear rule.
I think that these populations ought to be mentioned as it will raise awareness and increase chances of their spread or demise being documented.
In this thread, there is quote
There might a rule for ABA as well, both from the other side of the pond
Niels
The text accompanying the Spanish map says that the diet consists principally of invertebrates (60%, reaching 90% in spring).
Thanks John, is this local knowledge, or is there a paper on this? Can you supply a reference, even if it is in Spanish? Nothing wrong with local knowledge, of course it should be taken into account too, but the power of the pen puts a time and place to this.
Thanks, that's very interesting.The following paper provides a summary of the origin of the Alicante population. In Spanish, with a short English summary included
Pujol J.A, Saez Izquierdo. Rabilargo ibĂ©rico (Cyanopica cooki) (2015) In: Atlas de las aves nidificantes en la provincia de Alicante, Edition: 2015, Publisher: Universidad de Alicante · SEO Birdlife, Editors: G.M. LĂłpez Iborra, A. Bañuls Patiño, A. ZaragozĂ Llenes, J. Sala Bernabeu, A. Izquierdo Rosique, J.E. MartĂnez PĂ©rez, J. Ramos Sánchez, D. Bañuls Patiño, S. Arroyo Morcillo, J.A. Sánchez Zapata, B. Campos Rois, A. Reig Ferrer, pp.444 - 445
https://www.researchgate.net/publication/296846263_Rabilargo_iberico_Cyanopica_cooki and press "Read full publication"
"Some of the Torrevieja observations were of azure magpies carrying plastic rings in the legs, in particular in 2008 (Palmer, 2008) and 2011 (LĂłpez, 2011)"
It maybe just a coincidence, as probably is due to other factors, but Iberian Imperial Eagle, which more or less shares the same overall distribution/habitat as Azure Magpie in the peninsula is spreading quickly to the East during the last ten years, with couples breeding right now very close to Alicante province limits. But with the important difference that its spread is continuous, without the gaps shown by Azure Magpie distribution
The following paper provides a summary of the origin of the Alicante population. In Spanish, with a short English summary included
Pujol J.A, Saez Izquierdo. Rabilargo ibĂ©rico (Cyanopica cooki) (2015) In: Atlas de las aves nidificantes en la provincia de Alicante, Edition: 2015, Publisher: Universidad de Alicante · SEO Birdlife, Editors: G.M. LĂłpez Iborra, A. Bañuls Patiño, A. ZaragozĂ Llenes, J. Sala Bernabeu, A. Izquierdo Rosique, J.E. MartĂnez PĂ©rez, J. Ramos Sánchez, D. Bañuls Patiño, S. Arroyo Morcillo, J.A. Sánchez Zapata, B. Campos Rois, A. Reig Ferrer, pp.444 - 445
https://www.researchgate.net/publication/296846263_Rabilargo_iberico_Cyanopica_cooki and press "Read full publication"
"Some of the Torrevieja observations were of azure magpies carrying plastic rings in the legs, in particular in 2008 (Palmer, 2008) and 2011 (LĂłpez, 2011)"
It maybe just a coincidence, as probably is due to other factors, but Iberian Imperial Eagle, which more or less shares the same overall distribution/habitat as Azure Magpie in the peninsula is spreading quickly to the East during the last ten years, with couples breeding right now very close to Alicante province limits. But with the important difference that its spread is continuous, without the gaps shown by Azure Magpie distribution
There is a paper on the diet here.
http://fernando-alvarez.com/pub/6.pdf
Puts it at 50% animal, so not the paper on which the previous text is based.
Thanks for the link occasional. This does seem to confirm that scientific proof is superior to beliefs or hunches however well intentioned. I'm not discounting Nutcracker's claim, yet. It will be interesting to see the fruits of his research!
It's not a perfect match but the distribution of the species broadly matches that of Stone Pine (see map) with the exception of warmer Mediterranean areas towards the coast (and perhaps wetter colder areas to the north-west). Perhaps some sort of climate requirement is a limitation but it's tempting to wonder if they might now survive in areas in France, NE Spain & even Italy with Stone Pine had they not been 'trapped' in the peninsula.
I'd think that's as good as anything findable at the moment; 50% certainly sounds more reasonable than the up to 90% animal mentioned before.
Much of the distribution mapped there for Pinus pinea is naturalised from ancient human cultivation, not wild. Rikli (Das Pflanzenkleid der Mittelmeerländer) concluded it was truly native only in Iberia; map below with green = native, purple = naturalised / cultivated:
It wasn't radically different to the first - 50% as opposed to 60%. The 'reaching 90%' was for spring, i.e. I presume equating to the breeding season - not uncommon to see increased importance of invertebrate matter in this season.
Long-cultivated plants are actually harder to track; Pinus pinea has been cultivated for ~6,000 years - probably one of the earliest cultivated plants of any (along with Date Palm, Wheat, and a few others from the Med region). One difficulty is distinguishing between traded seed, and seed grown locally, in the archaeological record. With pines, there's the additional problem that the pollen can't be identified to species level, and macrofossils are rare as they don't tend to grow in habitats that favour fossilisation.Ancient introductions are always tricky to be sure about but I'd guess a plant that provides food is easier to track in the record.
But it's the 90% figure that's particularly unlikely ...