I am uncertain whether this project ever materializes, but it is cool to consider it as a thought exercise.
Economically it is sound. The Netherlands has pelicans in many zoos and bird parks. If the project is evaluated from a purely business standpoint, benefit from visitors coming to see pelicans will be bigger than the cost of commercial fish eaten. A minor problem may be fishermen over-estimating loss of commercial fish.
Translocating wild adults? Not. Adults are likely to be especially attached to the existing wild breeding place, and might attempt to migrate back, or not adapt to a new place.
Translocating wild juveniles and immatures? It was my first thought. It is cheapest and fastest. The colony at lake Mikiri Prespa in Greece has over 1000 pairs, and produces enough young. Removing some juveniles may actually be not a loss, because overcrowding and density-limiting factors could be already in place. Translocating wild animals is normally the most successful method. It carries no problem of teaching zoo young to survive. Therefore, translocating wild juveniles would be worth even as a trial with full understanding the risk they might disperse or even migrate back to SE Europe. Reintroduction projects, in my opinion, suffer from over-organization and slowness. The biggest problem could be getting permissions to catch wild birds in Greece.
Start a colony of zoo birds, let them breed and release the young? Not realistic in my opinion. Breeding of pelicans fails in many zoos. A new colony may not breed or may produce too few chicks. Currently, no zoo colony reliably produces double number of dalmatian pelican chicks per year, which is required to realistically create a wild population. In the best situation, such a colony would need decades to produce enough young, and would need to be maintained all these years. A possible additional problem is that year-round presence of adult pelicans may prevent the young from developing natural feeding skills and winter dispersal. So adult pelicans should be removed for winter, and this will create additional disturbance.
Releasing zoo-bred young? Possible. Zoo-born pelicans can learn to survive in the wild, as proven by a number of escaped pelicans which lived wild in the Western Europe for many months. European zoos collectively produce enough young Dalmatian pelicans every year to make it just viable.
Let the pelicans choose a breeding place themselves? No. Safe breeding places for pelicans are naturally very rare, and often fail. Wild pelicans often select artificially made breeding platforms. Also, with no anchor of a breeding site, possible problem is young losing and not finding each other.
Select a breeding place and anchor released birds to it? Yes, in my opinion. Released pelicans should be attached to the breeding place by presence of released zoo pelicans, or by dummy sculptures of pelicans. The latter was successful once with wild pelicans in the Balkans. Live pelicans are better, in my opinion. Juveniles should be kept confined for few weeks around the platform, to ensure they learn the place rather than e.g. immediately fly away long distance.
Should the breeding colony be very remote, with birds possibly afraid of humans, or close to humans? I feel the remote place is preferable, and care should be taken than the pelicans at least theoretically can forage and survive themselves. Such colony should be watched and cared by staff limiting contact to minimum, possibly from a hidden passage. Hooking the pelicans to people could endanger the birds, both because human provisioning is unreliable, killing by vandals, and potentially turns the pelicans into nuisance to those people who don't like them. Nevertheless, it is possible that the released pelicans become fearless by themselves. Wild pelicans became fearless fishery scavengers in several countries including Greece and South Africa. Wild Grey Herons in the Netherlands are commonly urban scavengers, too. Also, an apparently wild vagrant pelican in the Netherlands recently was tamed by the public feeding it fish over several weeks.
Supplement wild or zoo-reared juveniles after a core group of birds exist? Yes. Pelicans are slow breeding, and vulnerable to chance factors. Such supplementing should be at least tried to speed up creating the viable population.
One place or more? One place is the only realistic option. However, several alternative places may be preferable if not realistic. Recent, reintroduction of other birds like Northern Bald Ibises, California Condors or Whooping Cranes met problems, because the place selected by people was after several years found to be unsuitable, because of subtle factors not imagined before (bloodsucking insects, poisoned food, illegal hunters, collisions with power lines).
