With crossed fingers, caretakers backed out of the Hawaiian foliage last year after five hand-raised , or 驶Alal膩, and into their native forest. The species had been extinct in the wild since 2002, and this was the 驶Alal膩 Project鈥檚 defining moment: Would these five birds be able to establish a new population?
They were not. Within a month, three members of the cohort died鈥攖wo from hawk attacks and one from unnamed environmental stressors. Efforts to save the wild 驶Alal膩 population date back to the 1970s, and the project is the most recent attempt to achieve establish a new population. After the first three deaths, though, the researchers quickly and brought the two survivors back into captivity.
Now, a little more than a year later, the team has tried again, and a new group of 驶Alal膩 have ventured into the Hawaiian wilderness. The project released 11 crows鈥攖wo of which were last year's survivors鈥攊n the past couple months. A was released into the Pu鈥榰 Maka鈥榓la Natural Area Reserve on the big island of Hawaii on September 26, and entered the forest in a slightly different location on October 11. With more than twice as many birds venturing into their native habitat than last time, the researchers are optimistic that this new crop will thrive. Since the last year's introduction, the team overhauled its reintroduction strategy鈥攅specially the methods for acclimating 驶Alal膩 to predators鈥攁nd believe the bird's are much better prepared this time around.
The first loss served as a painful reality check. 鈥淥ur team had been working very hard, for months and years even, to raise these birds鈥攆rom being laid as an egg to hatching out, and then being released into the wild,鈥 says Bryce Masuda, a San Diego Zoo Global conservation program manager who works on the project. 鈥淚t was really difficult for all of us.鈥 At the same time, 鈥渢he outcomes were also a learning experience,鈥 says Jackie Gaudioso Levita, the project coordinator for the .
For one, this time the team made sure the birds would stick together in the wild. For almost nine months, the researchers observed each crow鈥檚 behavior before and after feeding, taking note of who was pushy, who begged, and who got to the feed bowl last. Dinner time manners indicate social hierarchies for 驶Alal膩, so the team parsed the two groups based on which individuals were most likely to get along.
Then training for the wild really began. The number one priority was teaching the 驶Alal膩 to recognize and avoid the , a native Hawaiian hawk. Though the team taught the crows to dodge their natural predator before the 2016 release, this year's batch received what Masuda calls 鈥渁 suite of stimuli鈥 meant to 鈥済et the 驶Alal膩 riled up鈥 during 鈥业辞 attacks.
The system the team used imitates the natural process of events when the hawks hunt. First, the birds heard playbacks of 鈥业辞 hunting calls; then, they saw a taxidermied version of their foe soar overhead. Recordings of 驶Alal膩 warning cries were next broadcast through speakers, and for the finale, a live 鈥业辞 in an adjacent cage flapped its wings. Levita and her team tested the drill on older, breeding crows first to make sure they squawked and took notice of the faux danger.
During all of the sorting and training, the team also scoped out drop-off locations within Pu鈥榰 Maka鈥榓la using a new tactic often used by business strategists. Called (strength, weakness, opportunity, and threat) analysis, the method helped the researchers weigh factors like 鈥业辞 scarcity, native fruit abundance, and accessibility for daily research monitoring.
All these efforts culminated in a delicate introduction for the birds. First, the crows moved to a pseudo forest environment鈥攁n aviary within the Pu鈥檜 Maka鈥榓la鈥攗ntil they settled down. Then, when the doors were finally flung open, each 驶Alal膩 wandered out on its own time, explained Masuda. Some zipped out immediately; others lingered in the comforts of home for hours.
Now the team waits. Until the birds' foraging habits fully kick in, San Diego Zoo employees will supply them with extra food and monitor their weight using feeders equipped with small scales. So far, though, the 驶Alal膩 are fending for themselves fairly well. They strip bark from trees to get at insects and find native berries to snack on鈥攁 process that's important for indigenous fruiting plants, which could use the dispersal boost from crows scattering their seeds.
When the year of observation ends, the birds should be completely independent and ideally will have established a baseline population in Pu鈥檜 Maka鈥榓la. Levita and her team plan to continue breeding in captivity and introducing younger batches of 驶Alal膩 into the forest with their relatives, eventually building a flock that can boost their numbers on their own. And seeing as the group of six from September have already out-survived the 2016 cohort, the team has reason to be hopeful.
Locals are also rooting for the project's success. 驶Alal膩 represent ancestral guardians in Hawaiian culture, and their presence or calls signify warnings of future misfortunes. Since the 驶Alal膩 Project's creation, team members have given presentations at community centers and schools to update the region's residents on the bird鈥檚 progress. And when they announced the three deaths last year, people showed up in droves to learn what happened and how the project planned to move forward. With the latest round of releases, the locals are even more invested鈥攖hey voted online to give each of the 11 驶Alal膩 a native Hawaiian name. This, Levita says, shows that the birds are just as integral to 鈥渢he cultural fabric of the Hawaiian islands鈥 as they are to the ecosystem they belong.
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