BirdLife's Globally Threatened Bird Forums
Eclectus Parrot (Eclectus roratus) is being split: assessment of newly recognised taxa.
Posted on May 23, 2019 by Red List Team (BirdLife International)
Following a taxonomic reassessment investigating the findings of Braun et al. (2016), Eclectus Parrot is being split into four species; Moluccan Eclectus Eclectus roratus, Papuan Eclectus E. polychloros, Sumba Eclectus E. cornelia and Tanimbar Eclectus E. riedeli.
The pre-split species was listed as Least Concern. The population was judged to be declining due to the dual impacts of trapping for the cage bird trade and high rates of habitat loss in parts of the species’s large range. Nevertheless, the overall rate of this decline was not thought to approach the thresholds for listing as threatened under Criterion A, the range greatly exceeded the thresholds for Criterion B, and the total population size was unknown but thought to considerably exceed the thresholds under Criteria C and D. Despite being legally protected in Indonesia, trade continues to be noted throughout the range (Cottee-Jones et al. 2014, Collar et al. 2019).
The reduced range size, and likely population sizes of the newly defined taxa may result in one or more qualifying for listing as threatened. For the newly recognised Moluccan and Papuan Eclectus, an initial assessment (see below) suggests that while they are considered to be declining, they are not considered to approach the thresholds for listing as threatened under the IUCN Red List (IUCN 2001, 2012). Constructive comments are still welcome on these judgements. However, Sumba Eclectus and Tanimbar Eclectus meet initial thresholds for listing as threatened, hence are assessed against all criteria.
Of importance is that there is a revised estimate for the generation length of the pre-split species of 12.7 years (BirdLife International in prep.). Here this is used for each of the newly recognised species to define the three-generation period over which to assess population decline, rounded to 38 years.
Moluccan Eclectus (E. roratus) – The new nominate species includes the two subspecies voesmaeri and roratus, and is restricted to the Moluccas, being known from the islands of Morotai, Halmahera, Ternate, Bacan and Obi (including some smaller islands), and Buru, Seram, Ambon, Haruku and Saparua (Collar et al. 2019). The newly calculated Extent of Occurrence (EOO; IUCN 2001, 2012, Joppa et al. 2016) is 234,950 km2, greatly exceeding the range-size criterion for listing as threatened under Criterion B1 (EOO < 20,000 km2).
A recent survey within the range indicates that the population remains large: on Halmahera, the population just in the Aketajawe-Lolobata National Park was estimated at 4,463 individuals in 2012 (Bashari 2012), which suggests that the overall population on Halmahera is close to 10,000 individuals. The density estimate here was 5.9 individuals/km2, which is similar to the density recorded on Seram (7.4-13 individuals/km2; Marsden 1998, 1999), and Buru (1.9 – 13 inds/km2; Marsden 1999). All populations together likely exceed the population size thresholds for listing as threatened (< 10,000 mature individuals for Criterion C, < 1,000 mature individuals for Criterion D).
However, there are concerns over the impact of trade in parts of the range. While a status assessment of the threat to parrots within the Moluccas in the 1990s did not consider Eclectus to be a priority (Widodo et al. 1999), a recent estimate of 810 (± 153) individuals harvested annually for trade on the island of Obi (Cottee-Jones et al. 2014) appears rather high. The species was found to be uncommon on Obi (Mittermeier et al. 2013; Cottee-Jones et al. 2014), and it was traded at almost double the price of any other parrot species in the bird market. While Obi is a small part of the range and the species persists there, this population appears severely threatened (Cottee-Jones et al. 2014). Lambert (1993) reported that the species was far rarer on Obi than on Bacan or Halmahera, so this may represent a real suppression of numbers by trapping. With densities elsewhere being higher, the concerning situation on Obi indicates that it is reasonable to infer that the population is declining, but that overall the rate of decline is unlikely to approach the threshold for listing as threatened under Criterion A (>30% decline in three generations). Consequently, Moluccan Eclectus is proposed to be listed as Least Concern.
Papuan Eclectus (E. polychloros) – Papuan Eclectus (E. polychloros)includes the subspecies aruensis, biaki, macgillivrayi, and solomonensis. Its range extends from the west Papuan islands (Gebe [Rothschild and Hartert 1901] including Gag Island [Johnstone 2006], Kai Islands, Aru Islands and Biak throughout lowland New Guinea, the Admiralty Islands through the Bismarck Archipelago and the Solomon Islands (except St Matthias, Nissan and Rennell), to the extreme north of Queensland, Australia (Collar et al. 2019). The EOO is 3,770,141 km2. It is considered that while the population may be declining due to trapping and habitat loss, the rate of decline is unlikely to approach the thresholds for listing the species as threatened under Criterion A (>30% decline in three generations).
Several estimates of population density exist, of which many indicate relatively high densities in excess of 10 individuals/km2. For example, densities on New Britain were estimated at 16 individuals/km2 in primary forest and 25-72 individuals/ km2 in logged forest and forest gardens (Marsden and Pilgrim 2003). In lowland rainforest on mainland New Guinea, densities were 10 individuals/km2 (Bell 1982), while the density in hillforest (between 430-950 m) was 11.3 individuals/km2 (Marsden and Symes 2006). The population on New Britain alone would therefore likely exceed thresholds for listing under the population size criterion. Overall, Papuan Eclectus is considered to have a large population and is not believed to approach the thresholds for listing as threatened. Papuan Eclectus is therefore proposed to be listed as Least Concern.
The other two newly-defined taxa have restricted ranges. Sumba Eclectus E. cornelia is only found on the island of Sumba in the western Lesser Sundas, and Tanimbar Eclectus E. riedeli on at least Yamdena Island and Larat (Bishop and Brickle 1999). As they meet the initial thresholds for listing as threatened, they are here assessed against each Red List criterion in turn.