Indonesia added 18 new species of birds, bringing the total number to 1812 this year. The cause of the increase in this number is taxonomical splitting. In 2020, Central Superb Bird-of-paradise (Lophorina feminina) and Purple-chinned Starling (Aplonis circumscripta) were splitted into four different species, adding two new species to the list of Indonesian birds.
Central Superb Bird-of-paradise and Purple-chinned Starling was previously categorised as a subspecies of Western Superb Bird-of-paradise (Lophorina superba) and Metallic Starling (Aplonis metallica), respectively. Both are categorized as separate types because they have different morphological characteristics based on the latest analysis. Moreover, rapid development of technology and increasing public interest in bird watching activities have also contributed to the development of the world of ornithology and conservation. Report on observations through the citizen science observatory, such as e-Bird, recorded 16 additional species to the list of birds in Indonesia.
One of these species that should be highlighted is the Beck’s Petrel (Pseudobulweria becki), currently categorized as Critically Endangered (CR) by the IUCN. This species was previously known to only be distributed in the Bismarck Islands, Papua New Guinea and Solomon Islands (del Hoyo et al., 2020), but its presence in Halmahera has recently been observed.
Based on their threat status, there are 179 bird species included in the global list of threatened birds. Among them, 31 species are in a brink of extinction or in Critically Endangered (CR) category, 53 species are declared as Endangered (EN) and 96 species are Vulnerable (VU).
“This implies increasing conservation challenges of bird’s biodiversity in Indonesia. Despite the large number of conservation efforts, half of the bird's populations in nature will still be deteriorating,” said Achmad Ridha, Biodiversity Conservation Officer of Burung Indonesia on Wednesday 28th April 2021 in Bogor.
Aside from deforestation, hunting and capturing birds from the wild are currently the main cause of population decline and contribute to the increase in the threat status of nine species this year. The species that are directly affected are Scarlet-breasted Lorikeet (Trichoglossus forsteni), Browned-cheeked Bulbul (Alophoixus bres), Gray-cheeked Bulbul (Alophoixus tephrogenys), Aceh Bulbul (Pycnonotus snouckaerti), and Chestnut-capped Thrush (Geokichla interpres).
Browned-cheeked Bulbul is now estimated to have decreased by up to 50% of the original population in its distribution area on the islands of Java and Bali (BirdLife International, 2020a; Eaton et al., 2015). This condition affirms the importance of more serious efforts in reducing the impact of hunting and capturing birds from the wild.
On the other side, threat status of some species has actually decreased, namely Japanese Night-heron (Gorsachius goisagi), Kai Cicadabird (Edolisoma dispar), and Asian Woollyneck (Ciconia episcopus). Those species are now known to have a relatively wide distribution area with relatively stable conditions, thus declining their threat category (IUCN, 2020).
Achmad Ridha Junaid explained that based on the IUCN, the decline doesn’t always indicate a species population recovery in the wild. In some cases, the addition of information in determining the criteria can lead to a decrease in the status of threat, such as happened to the Japanese Night-heron, Kai Cicadabird, and Asian Woollyneck.
This is different from Bristle-thighed Curlew (Numenius tahitiensis) which is experiencing a decrease in threat because in recent years the hunting intensity has decreased and there are signs that the species population is recovering in some parts of its home range (BirdLife International, 2020b). “On the contrary, the status of Javan Oriole (Oriolus cruentus) has lowered into the Data Deficient/DD category due to the lack of record of encounters of this species, thus needing deeper evaluation regarding its threat status. Currently, Javan Oriole has become one of species with least information in Java Island,” he said.
BirdLife International noted that Indonesia is home for at least 17% of the number of bird species in the world and is in 4th position in bird species richness. However, based on its endemicity, Indonesia is in the 1st position that has the most endemic bird species in the world.
Until 2021, Indonesia has recorded 532 endemic bird species. Records increased in 2020, which is as many as 16 types of bird. There are at least seven new species of birds found in the Wallacea region, while nine others sourced from taxonomic breakdowns. The study on the status of bird species carried out by Burung Indonesia is expected to become a reference to the most up to date information on bird species diversity in Indonesia. “As an organization focused on bird conservation and its habitat, it is hoped that this data will not only be a reference to the conservation efforts, but also become product knowledge that can be referred to by the public,” Ridha concluded.