The Village Behind the Egg: ʻAnianiau Conservation Begins

Blog Post by Abigail Bernier

This field season, much of the bird crew has been focused on collecting ʻanianiau eggs for the breeding conservation program, allowing us to have a population under human care for eventual release back into the wild. The forest birds face many threats currently, including avian malaria transmitted by invasive mosquitoes. We have been fortunate enough to be able to start work such as IIT, or incompatible insect technique, to reduce these mosquito populations. However, forest bird populations continue to decline even as mosquito control is being implemented.

Conservation Breeding Programs for ʻakikiki and ʻakekeʻe have already been established, laying the groundwork for other honeycreeper species. While the ʻanianiau population is still larger than the critically endangered ʻakikiki and ʻakekeʻe, our research shows that are declining significantly. ʻAnianiau are endemic to Kaua’i, meaning they are native to and only found on this island, and nowhere else in the world. To combat the risk of extinction, we have poured our resources into collecting clutches of ʻanianiau eggs that are sent to a specialized breeding facility, run by San Diego Zoo Wildlife Alliance (SDZWA), where teams of experienced scientists will hatch and raise the chicks. Meanwhile, last fall we collected a dozen adult ‘anianiau, most of which are at the Honolulu Zoo.

Before we can collect eggs, many hours of work go into finding and monitoring the nest. Following adults, watching mating behaviors, observing nest building, and peeping the nest (using an extendible pole with a GoPro attached for viewing) are just a few of the things that need to happen before a collection can be considered. The timing of a nest collection is also important for egg survival. The embryo is very fragile in the early days, but on the other hand, we don’t want to wait too long to avoid hatching during transport. Once determined that there are eggs and the nest is reachable, a free-standing ladder must be extended and set up using a rope to suspend it. The tree canopy and nest are very delicate, so we spend hours making sure we will not disturb the tree the nest is in and that the person collecting the eggs can do so safely. It takes a minimum of 6 people for this process and ample time to prepare the ladder for use. The ladder is extendable and when both pieces are connected weighs around 100 lbs. Even when the two portions are separated, it can be very difficult to carry the ladder for long distances through dense vegetation. If moving the ladder far, we often try to have a helicopter move the ladder attached to a longline. However, we are often in a closed canopy, so we still must carry the ladder to an area open enough to attach and sling the ladder closer to the nest location. The number of moving parts in a nest collection is astounding and requires great communication and teamwork from everyone.

On April 14, the first ʻanianiau nest was collected. The female had laid two small, white and speckled eggs, weighing about 1.5 grams each (half the weight of a penny). One of our aviculturists, specially trained in egg handling and collection, carefully climbed the ladder, high into the canopy. They then delicately reached into the nest to grasp each egg before putting it in a container filled with millet (to keep the eggs from moving around) and lowering it down to waiting arms at the bottom of the ladder. The eggs must be continuously incubated while in transport, so they are then placed into our portable incubator, powered by a battery and fitted in a cooler for insulation. Because this is a time-sensitive process and the portable incubator only has so much power, the eggs must be flown out of the field via helicopter at the earliest opportunity. Just after the eggs had reached the ground safely, they were hiked to the nearest spot a helicopter could land and transported with a team member. Timing the journey out of the field can be difficult, as weather conditions can change rapidly, and the helicopter pilots often only have a short window of time for our helicopter operation as part of their day. Typically, before being transported off-island to a SDZWA facility on Hawai’I Island, they will stay in our ‘egg-house’, where they receive 24/7 care in a proper incubator for a day or two. Luckily, these eggs were able to leave the island the same day for their new home.

Several days later, one of the eggs hatched. It was an exciting moment for members of our team and forest bird lovers alike, the first ʻanianiau egg we had collected hatching in human care. It signaled a hopeful start to our collections, as we prepare for more soon. This truly would not have been possible without the hard work, dedication, and care of our team and SDZWA, as well as the love and support we have received from our community for the conservation of these forest birds. Unfortunately, the other egg did not hatch, as the embryo was later found not to be properly developed. This is sometimes the reality in nature; not every egg will survive. However, we are finding more ʻanianiau nests with eggs and hope to collect more in the coming weeks. We will be contributing further to the captive population, which will act as an insurance policy if this population were to decline beyond the ability to recover naturally.

Mahalo for your support and sharing in our hope for the ʻanianiau. You can continue to follow the journey of our nest collections and the chick on our social media, as well as follow along on our blog for updates and news.