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
-
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
Iberian Magpie (1 Viewer)
- Thread starter Andy Hurley
- Start date
Just when I was hoping they might be crossing the Channel soon . . . :-O
John Cantelo
Well-known member
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
There might a rule for ABA as well, both from the other side of the pond
Niels
Cheers Niels
occasional
Well-known member
On the page details, I'd say more should be made of the importance of acorns and Stone Pine Pinus pinea pine nuts in the diet - they from the bulk of the diet, with large amounts cached for later use (invertebrates etc., only secondary importance). The species is the main natural dispersal agent for Pinus pinea, with their native ranges nearly coincident.
The text accompanying the Spanish map says that the diet consists principally of invertebrates (60%, reaching 90% in spring).
The text accompanying the Spanish map says that the diet consists principally of invertebrates (60%, reaching 90% in spring).
Nutcracker
Stop Brexit!
I wonder how accurate that is? There used to be similar statements for Eurasian Jay until quite recently, as the importance of acorns cached the previous autumn had been massively overlooked in earlier research. I'll try to find the references.
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 ibérico (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. López Iborra, A. Bañuls Patiño, A. Zaragozí Llenes, J. Sala Bernabeu, A. Izquierdo Rosique, J.E. Martínez Pérez, 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 (López, 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
Pujol J.A, Saez Izquierdo. Rabilargo ibérico (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. López Iborra, A. Bañuls Patiño, A. Zaragozí Llenes, J. Sala Bernabeu, A. Izquierdo Rosique, J.E. Martínez Pérez, 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 (López, 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
Last edited:
John Cantelo
Well-known member
Thanks, that's very interesting.
occasional
Well-known member
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.
http://fernando-alvarez.com/pub/6.pdf
Puts it at 50% animal, so not the paper on which the previous text is based.
Thanks very much for this Fernando. I agree that research is needed to comfirm/refute any connection in range growth. Like you I think it is likely to be coincidental, because of the 200 km gap in Iberian Magpie distribution and the likelihood that the Torrevieja colony seems to be an organised attempt by one or more individuals to introduce the species to the area.
Last edited:
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!
Nutcracker
Stop Brexit!
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. Unfortunately my Spanish isn't good enough for reading the paper, but the English summary certainly picks out the importance of Stone Pine Pinus pinea seeds (the 'pine nuts' you get in Mediterranean food shops).
John Cantelo
Well-known member
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.
Attachments
Nutcracker
Stop Brexit!
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:
Attachments
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.
John Cantelo
Well-known member
Interesting. The two maps seem to agree on the native distribution across most of Spain (and is perhaps slightly more detailed in the map I posted). They clearly diverge regarding the status in NE Spain and elsewhere further to the east. 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.
Nutcracker
Stop Brexit!
But it's the 90% figure that's particularly unlikely - other similar seed-storing corvids (particularly Nucifraga, but also Garrulus) used also to be thought to be primarily invertebrate eaters in the spring, but are now known to be primarily reliant on seeds stored the previous autumn, both for their own food, and for feeding their chicks. See R. M. Lanner, Made for Each Other - A Symbiosis of Birds and Pines (Oxford UP 1996).
Nutcracker
Stop Brexit!
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.
Doesn't seem unlikely to me.
2002 study of diet of this species found 99.6% of nestling diet consisted of terrestrial invertebrates. Only a small amount of vegetable matter was found, this assumed to have been unintentionally collected during the hunting of these invertebrates. Outside breeding season, 50-60%.
2004 study looked at breeding performance of this species in years of different weather conditions and identified invertebrates as the main element of the diet during this period, further finding that reduced abundance of invertebrates impacts breeding parameters, e.g. leads to smaller clutches.
"The amount of rainfall has a marked influence on invertebrate abundance, the main elements of nestling and adult diet in this species.... Rainfall also affects invertebrate phenology, and especially availability, .... So, as expected, there was a strong year effect on most breeding parameters."
Last edited:
