Thank you Prof. Jones for your clarifications.
I agree that releasing Echo Parakeet fledglings into an area where there are already flocks of wild Echos which the new young birds can imitate, follow and learn from is a much simpler job than trying to release Spix Macaws into the wild where there are no Spixes to act as teachers.
It would seem that some Spix fledglings would be more apt at quick learning about feeding on new foodstuffs, predator avoidance, safe sleeping spots and the like, while other individual birds would be more likely to depend upon human supplemental feed stations, staying close to the release site aviaries and the like. That is why I believe that an extended period of training would be helpful for such fledglings in order to determine in a free flighted situation which birds are the more apt learners.
Mr. Watson’s observation that:
[parrots held back in captivity too long do not develop to the same extent of parrots fledged into the wild or parrots released from captivity at a young age.]
This may have proven true in Mauritius, though I would venture that this concept depends totally upon HOW the parrots are kept in captivity, whether they are allowed out free flying regularly in rough topography with plenty of wild browse foodstuffs, and whether they are single males, single hens or paired bonded parrots. Also what they have been exposed to in terms of danger and flock dynamics prior to release.
Echo Parakeets are fast, elusive flyers that are quick to take off, adept at changing direction and have a common flock personna that when grouped in numbers provides extra protection against in flight dangers. The sizeable Spix is a different entity, being slower to emerge from perched positions, bulkier in flight maneuvers and landings, hence decidedly more vulnerable to say raptor attack.
Now if single Spix fledglings were released in an area that had older single birds already smart in survival and feeding methods, then it would be advantageous for these new birds to pair up with an opposite gender parrot for safety and education. Fleglings, however are dependent upon their parents until sexually aware enough to begin a friendship bond with another Spix, therefore releasing fledglings with no parental guidance, nor any predisposal to pair for later propagation, would work against the possibilities of the bird being more than a “loner” amongst other fledglings. If the fledglings are kept together in captive situation long enough to begin pairing up, then the program would most likely have a higher success rate releasing birds in young pairs.
Some added observations:
Mr. Watson says: [Why would we release birds which are reproductively compromised?]
Well, they would be released for their experience and savvy in a flock of reintroduced Spixes! Why would a conservation program wish to keep them in captivity if they were reproductively compromised? Unless of course they were being used profitably to train youngsters—otherwise such birds are at a dead end conservation wise and should be imaginatively employed in a differing role.
Also he mentions: [Currently there is 66 Spix’s Macaws in the program and we need to reach a population size of approximately 120-150 before releasing birds]
That implies that it will be many years before fledglings will be available as the70 or so birds needed to make up that number will be aging by many months if not years prior to reachin a 130 bird goal. Twould seem plausible to be training all such birds in a safe area so that the intelligence and potential survival of the entire group in captivity goes up as the years go by, rather than remaining static in a program focused on only propagation of the needed numbers. Even having a breeding facility on site of future release would be preferable (If feasible) as the nuances of survival learned by outdoor caged birds in the environment they are going to be in are varied and subtly necessary—even behind wire or with daily sojourns out of cage.
As to this: [Unfortunately there is 2 entrenched beliefs in the parrot world that are simply not true, the first is that released birds need a wild teacher in order for them to succeed post release and the other is that parrots need to be trained how to behave like wild birds in a captive environment first before being released]
Of course I would not state that released birds NEED a wild teacher. But having one is of enormous benefit to fledgling parrots who imitate and follow and learn daily—that is why fledglings spend so much time in the company of their parents in the wilds—learning species specific survival skills. And teaching release prospects how to behave in the face of danger or how to find water sources or which seeds are ripe when and where are things that humans have a hard time conveying. Releasing young birds with a huge learning window post-fledgling and expecting them to pick up so many such lessons by themselves is asking a lot. Not impossible, but higher risk to be sure.
I would expect if any Spix release were accomplished in the future, it would be more like a wild animal park, freed of as many dangers (including humans) as possible, with birds basically feeding at stations and then beginning to branch out into the environment as the months and years go by.
Should such a safe place be established, it would be a shame not to allow some formerly wild Spix birds, especially if reproductively compromised, to join a wild release group—lest the knowledge they have to pass on to captive born individuals be lost to the species forever.