Updated: Oct 30, 2019
Every week we will be highlighting and exploring a new species. Birds from exotic places, birds with unique traits, incredible rarities, and some species that can be found in your backyard!
Palila (Loxioides bailleui)
The Palila (pa-LEE-la) is a small species of Hawaiian Honeycreeper that can only be found in the upper slopes of Mauna Kea on the island of Hawai'i. It is the only finch-billed Honeycreeper that has not gone extinct. Approximately 2,000 birds remain on the island, a 66% drop from their estimated population in 2003. They are considered one of the rarest species of bird on the planet, due to their dwindling numbers, low reproduction rate and extreme isolation.
Palila have a bright yellow head and breast, grey and white body plumage, and olive-green on their wings and tail. They have a dark bill, dark brown eyes, and dark feet. While they are not distinctly sexual dimorphic, males do tend to have brighter coloration, and clear-cut black lores on the face. The females tend to be slightly less contrasting, and a bit smaller in size. On average they are between 6-7.5", making them one of the largest living Hawaiian Honeycreepers. They have a beautiful song consisting of whistling, and warbling and trilling notes that is communicated loudly between birds during feeding.
These birds depend upon the Māmane tree, also found only in Hawaii, for their survival. 90% of their diet comes from the seeds, which contain toxic compounds that can kill other small animals within minutes of ingestion. It is not known how Palila are able to safely eat these seeds. The toxicity of the individual māmane trees varies, and somehow the birds are able to avoid particular plants with pods containing the most toxic seeds.
Māmane tree produce food year-round, as the trees are varied in elevation and flower and produce seeds at different times throughout the year. Naio berries are the secondary food source of the Palila, though this only makes up a small percentage of their diet. They have been observed eating other fruits, such as the non-native Cape gooseberry, and caterpillars are fed upon by adults and given to nestlings unable to digest the toxic māmane seeds.
Female birds select a site for their nest, and the male will assist her in building it using stems, grasses, roots, and bark. These nests do not get reused by the pair. Their clutch numbers are low, averaging just 2 eggs. The embryos develop slowly, which increases the risk of predation. During droughts or when māmane seeds are scarce, birds may not even attempt to breed.
As a result of habitat loss, the Palila's status is critically endangered. Despite being one of the first species to be listed under the Endangered Species Act (listed as a Federally Protected Species in 1967, and changed to Endangered in 1973), their numbers are still under strain. Palila occupy less than 5% of their original distribution throughout the island, as suitable areas of māmane forests have been severely reduced by agriculture conversion and non-native grazing.
Introduced species pose a huge threat to the population. Mouflon sheep were brought to the are for sport hunting in the 1960's, and negatively impact the māmane forests by eating the saplings and trees. Domestic goats, cows, and other breeds of sheep also destructively graze in these habitats. Non-native predators like mongoose, rats, and feral cats eat eggs, nestlings and adult birds, and the Palila are also highly susceptible to mosquito-borne diseases.
The American Bird Conservancy's Hawaii Program includes the Palila as one of it's top priorities. They work with partners to restore native forests, install and maintain fencing to keep out sheep and goats, and control predators in Palila nesting areas. 90,000 trees have been planted on Mauna Kea through their program! The Hawaii Program is also working towards protecting other species of native birds, such as the Millerbird, Hawaiian Petrel, Newell's Shearwater, and the Maui Parrotbill, and relies on donations, volunteers, and awareness brought to these species.
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