Chapter 1: The Plight of the Orange-Bellied Parrots

A small group of orange-bellied parrot (Neophema chrysogaster) nestlings faces a critical situation. These Australian parrots are on the brink of extinction, with their population continuing to dwindle due to rampant logging and habitat destruction.

Remarkably, only two parrot species in the world undertake annual migrations between their breeding grounds in Tasmania and their winter habitats in southeastern Australia. Their journey involves navigating the treacherous Bass Strait, a challenging 240-kilometer (150-mile) stretch of water that poses significant risks.

These migratory parrot species, the orange-bellied parrot and the swift parrot (Lathamus discolor), are critically endangered. Their plight is exacerbated by habitat destruction driven by human activities, such as logging for toilet paper production. To counteract their declining numbers, both species are the focus of intensive captive breeding programs.

However, a puzzling trend has emerged: orange-bellied parrots bred in captivity often struggle to survive when released into their natural habitat. A significant factor limiting their recovery is the low juvenile survival rate during migration. Presently, the entire population of orange-bellied parrots is confined to a single breeding area at Melaleuca in Tasmania's southwest.

This situation raises an important question: which of the captive-bred parrots are more likely to survive their migratory journey? Can we identify these individuals to maximize survival rates upon their release?

Section 1.1: Researching Survival Rates

A study led by conservation biologist Laura Bussolini, a doctoral candidate at the Australian National University, aims to shed light on these questions. The research investigates juvenile survival rates among both wild and captive-bred orange-bellied parrots. Ms. Bussolini is dedicated to bridging the gap between scientific research and conservation management, focusing on practical questions and methods that could enhance efforts for endangered species recovery.

Surprisingly, both wild and captive-bred parrots exhibited similar survival rates during their first migration. However, heavier nestlings showed a notable advantage in survival, regardless of their breeding origin.

Hope for 'world's fattest' parrot as endangered kakapo have record-breaking breeding season - YouTube

The study reveals that nestling body condition significantly impacts survival. Ms. Bussolini noted, “There was a bit of variation in chick body condition by year in the wild population, as they respond to numerous factors like food availability, predators, and weather conditions.”

The order of hatching also affects body condition, with earlier-hatched chicks generally faring better.

Heavier nestlings are better equipped for survival.

Section 1.2: Implications for Conservation

Interestingly, wild-born nestlings consistently demonstrate superior body condition compared to their captive counterparts, highlighting a crucial research goal: to enhance the quality of captive-reared parrots.

The captive breeding program for orange-bellied parrots involves several hundred birds across multiple facilities. Selecting which juveniles to release into the wild is a complex task. Ms. Bussolini emphasizes that “nestling body condition is a valuable tool for identifying individuals with the best chances of survival after release,” and it can also help pinpoint those that may need additional support.

What about nestlings with lower body condition?

Ms. Bussolini reassures that “Just because individuals might rank lower in physical condition doesn’t diminish their overall value to the population.”

Chapter 2: Strategic Conservation Measures

The orange-bellied parrot is not alone; many species depend on effective conservation strategies for survival. This research indicates that while captive-bred individuals may differ from wild counterparts, they can survive just as effectively under the right conditions. The findings suggest that using an age-adjusted mass-to-size relationship could be a straightforward method for identifying suitable release candidates, enhancing post-release survival, and increasing the success of animal reintroductions.

The results underscore the need for a strategic approach to breeding programs, utilizing all available data to improve survival outcomes for critically endangered species.

Kākāpō: four facts about the world's fattest parrot - YouTube