ARTICLES ON HAWAIIAN
BIRDS AND BIRDWATCHING AND OTHER
Hawai'i's Endemic Forest Birds - Distribution, Status & Population Updates 2002
Hawai'i's endemic forest species are some of the most fascinating, beautiful and rarest species in the world. Unfortunately the populations of all species has declined dramatically in the past thousand years or so, ever since the arrival of man to the islands. During this period many species have become extinct and most of the other species remain at critically low numbers, only a few species appear to be managing to increase in numbers or retain their current population levels. The number of threats to Hawai'i's endemic birds are ever increasing and a combination of factors such as habitat loss, disease and competition from introduced species has ensured that the endemic species which live here will never be restored to their pre-human contact populations. The full history of Hawai'i's birds and their fight against extinction has been covered in many books and articles and so a detailed account is not included here, although the introduction paragraphs from the Hawaiian Forest Birds Conservation Assessment and Management Plan is repeated here below in its entirety.
Although the populations of forest birds are prone to fluctuations from year to year and cycle to cycle the general trend of the population levels and changes in Hawai'i are fairly consistent, and on the whole are a downward trend. It seems very likely that at least two more species will soon be lost from the avifauna of the Hawaiian Archipelago - the 'Alala or Hawaiian Crow and the Po'o-uli, both species have populations which are near to extinction. Figures quoted in the text and tables below are only estimates or trends and should not be regarded as totally accurate.
The following article gives a species by species account for all the Main Hawaiian Islands, with population data, population trends, habitat requirements, presence of captive programs and other relevant information. The three passerine species of the Northwestern Hawaiian Islands, Nihoa Finch, Laysan Finch and Nihoa Millerbird, are not included in these statistics as they have been dealt with in a previous account.
"Throughout the World, reduction and fragmentation of wildlife habitats and populations are occurring at a rapid and accelerating rate. In addition to the deterministic threats of habitat degradation and increasing resource use by rapidly expanding human populations, stochastic problems threaten the survival of small populations. Stochastic events tend to be random and difficult to predict, but nonetheless can be moderated by careful genetic and demographic management of small populations. As natural habitats decline, a large and growing number of taxa will need assistance and more intensive management to prevent extinction. Management methods developed specifically to address the problems of small populations, both in situ and ex situ, must be widely applied if the planet's biodiversity is to be maintained.
Preservation of island biodiversity is of particular concern. Endemic island populations are especially susceptible to extinction because of their small size, specialization in adaptation, vulnerability to environmental catastrophe, disturbance, introduced competitors and predators, and disease, as well as complex interactions between these and other factors. One of the most striking examples of the vulnerability of island endemics is in the Hawaiian Islands. these islands have the planet's highest percentage of endemic plant and animal species, and have already lost 27% of their endemic bird species known since the islands were "discovered" by Captain Cook (Pyle, 1990). There is little or no evidence that the species decline is slowing. If current trends continue, the United States will soon surpass Australia as the leader in the number of endemic extinctions.
The native avifauna of Hawai'i is faced with an extinction crisis that began with the arrival of humans and continues today. Among the hardest-hit in this extinction crisis have been the Hawaiian forest birds. In addition to the existence of the highest rate of endemism for birds, the Hawaiian Islands also have had more bird introductions (162 species) and more exotic bird species established (54) than anywhere else on the planet (Pyle, 1992).
The most recent checklist of the birds of Hawai'i (Pyle, 1992) lists 23 of the 71 endemic taxa known to have occurred in Hawai'i at the time of Captain Cook's exploration as presumed extinct. Those numbers may be conservative; the continued existence of as many as a dozen more species is seriously questioned: the Kama'o, Oloma'o, 'O'o'a'a, Bishop's 'O'o, 'O'u, Kaua'i 'Akialoa, Kaua'i Nuku-pu'u, Maui Nuku-pu'u, O'ahu Creeper, Moloka'i Creeper, Maui Akepa, and Po'ouli probably no longer exist (*1). For the most part these species were at extremely low numbers when last surveyed 10-15 years ago and have not been seen for years, and, based on detection failure in recent surveys, may no longer survive. If these species are added to the presumed extinct list, then 49% of Hawai'i's native resident bird taxa have disappeared (R. Pyle, pers. comm). Considering native forest birds alone, the percentage of taxa lost is even more alarming. Pyle (pers. comm, 2002) suggested that no more than five or six of the 12 species mentioned above are extinct as of 2002 (*1), although some have now been declared extinct as of 2004, and the others have not been seen for up to twenty years or more. In the worst-case scenario, if the 12 taxa listed above are added to the presumed extinct list, as many as 33 of the 57 small forest birds (58%) that are known from Hawai'i in historic times are or are now likely extinct.
The Hawaiian extinction crisis does not affect only those taxa which are highly specialized. Even the more common species appear to be at risk. One hundred years ago the most widespread forest bird species were the 'O'o and the 'I'iwi (P.Banko, pers. comm). The 'I'iwi no longer survives on west Maui and may no longer survive on Lana'i or O'ahu. It appears that the 'Amakihi no longer survives on Lana'i; similarly the Creeper is now gone from west Maui (*2).
There has been some progress toward actions needed to preserve and manage endangered forest bird species. Nearly 1,000,000 acres of habitat have been set aside in State Forest Reserves, Wildlife Sanctuaries, and Natural Reserves, with different levels of protection for each of these three types of state areas. Important forest bird habitat has been placed under protection in the Hakalau Forest on the island of Hawai'i, in the National Wildlife Refuge on O'ahu, and in large areas of forest habitat are protected in national parks on Maui and Hawai'i. Extensive ecosystem management has been instituted over the past 15 years. State, Federal, and private landowners are building fences, attempting to control ungulates and predators, protecting native plant communities, and reforesting degraded habitats. Critically needed research on limiting factors is underway and statewide forest bird surveys have been resumed to monitor bird populations.
In spite of these efforts, species continue to be lost. The trend appears to be one of a gradual, slow decline in small populations, and , to date, not a sudden collapse of larger populations. If this trend continues, those species that presently are already reduced to small population sizes, like the Puaiohi, will also soon be lost. It is not possible to determine, at present, whether more "common" species, like the 'I'iwi, are also on the same path to extinction.
The statewide forest bird surveys carried out by the U.S. Fish and Wildlife Service (Scott et al., 1986) from 1976-1981 have provided a useful assessment of forest bird numbers. When first published, these surveys were a comprehensive tool to evaluate the status of forest birds. Many of the population estimates in this document (*3) are based on these data.
As recently as 1976, little was known about the status of most Hawaiian birds; many areas within the islands were as yet ornithologically unexplored (Berger, 1972) because of the difficulty of survey under arduous field conditions within the island rain forests (Scott et al., 1986). While the status of many of the Hawaiian forest birds has been fairly well-documented, the integral role that may be played by some Hawaiian forest birds in the rain forest is not yet well-understood. It is possible that the role of many species within these ecosystems may not be elucidated before they become extinct. As such, it will be difficult to determine broader effects of species extinctions on the ecosystems as a whole.
As critical as the situation facing Hawaiian forest birds has become, and as urgent as the need is for immediate actions to halt the decline, the underlying factors causing the decline in forest birds are poorly understood. It has been suggested that competition for food with introduced taxa has played a significant role in the decline of many native species (Berger, 1981; Mountainspring & Scott, 1985). Other significant limiting factors include: habitat modification by humans as well as introduced domestic animals or exotic plants; disease, especially malaria; predation by exotics; genetic factors; as well as inherent problems with small populations. All are thought to affect forest birds to varying degrees but the relative importance of each is unknown. Still other limiting factors may not yet have been determined. At the very least, however, the likelihood of survival for Hawaiian forest bird taxa can be increased with more intensive management of identified limiting factors that are controllable, focusing on minimizing the effects of disease, predation by introduced exotic species, habitat loss and/or modifications, and competition with exotic species.
The successful preservation of wild species and ecosystems in Hawai'i as well as elsewhere necessitates development and implementation of active, integrated management programs by people and governments living within the range of the species in question". From the Hawaiian Forest Birds Conservation Assessment and Management Plan, 1992.
*1). Of these only the Po'o-uli is known to still survive as of 2002. No individuals were known to survive by 1/12/2004.
*2). The 'I'iwi no longer survives on Lana'i and is extremely rare on O'ahu; and 'O'o do not survive on any of the Islands (2002).
*3). The Hawaiian Forest Bird Conservation and Assessment Plan, 1992.
Recent sightings of all Endemic Hawaiian Birds can be found in the Reports Archive and Recent Sightings section (subject to reports being submitted).
Kaua'i's Endemic Forest Birds
PUEO (Asio flammeus sandwichensis)
The Pueo is still fairly common on Kaua'i and the island probably holds the largest population in the Hawaiian Archipelago. The Hawaiian Forest Bird CAMP (1992) estimates that one out of every three Owls seen or found dead on Kaua'i were of this species, although more recent declines in numbers of Barn Owls may have increased this ratio in favour of the Pueo. Disease appears to be a contributing factor to deaths of this species, although they are so far unidentified. Other factors which may affect the population are starvation and possible competition with Barn Owls, although Pueo tend to be mainly crepuscular and the Barn Owl is more nocturnal, which means that competition is perhaps less than one would expect. The species is not listed by any of the state or national conservation bodies and the Kaua'i population is an island population of the subspecies Asio flammeus sandwichensis.
KAMA'O (Myadestes myadestinus)
Extinct. The last documented sighting by a U.S. Fish and Wildlife Survey was in 1989. Although the species was reported several times in the Pihea Ridge/Alaka'i Swamp trail area these sightings must be regarded as rather unlikely due to the species range during that period and the small population. This species was tied habitat-wise more to the higher peaks and exposed mountain ridge-tops, which unfortunately aided its demise as Hurricanes Iwa and Iniki in the 1980's and 1990's ravaged the exposed mountains and forest on Kaua'i and destroyed much of the species preferred habitat. The last stronghold of the species was in the inaccessible area just below the peak of Mount Waileale. Additional threats to the species were disease, food competition, genetic factors, loss of habitat through introduced plant species and feral ungulates and although these factors were never conclusively proven there can be little doubt that they added to the species decline. Also known as Large Kaua'i Thrush. The 2004 IUCN Red List has declared this species as officially extinct.
PUAIOHI (Myadestes palmeri)
This smaller relative of the Kama'o inhabits the gullies and streambeds of the Alaka'i Swamp and thus was less affected by the severe hurricanes which affected the Kama'o, although even vegetation in the more sheltered areas was affected, with trees uprooted and non-native vegetation moving into previously alien-free areas. The species was still more common before the hurricanes with estimates of 176 and 97 between 1968, but only 20 in 1981. The fortunes of this species appear to have been reversed, both in the wild and through a captive breeding program. Birds which were bred in captivity were released at the end of the 1990's and shortly afterwards captive-raised pairs were seen nest building, and some wandered further afield and paired with wild-born individuals. The species is still listed as Endangered (USFWS), Endangered (IUCN) and Critical (Mace-Lande). Still a hard species to observe, but much easier in the last few years due to the increase in the population. The rarest forest bird that birders will see on Kaua'i. Also called Small Kaua'i Thrush.
KAUA'I 'ELEPAIO (Chasiempis sandwichensis sclateri)
The Kaua'i (sub)species is commonly found above 3,000 feet in the central portion of the island, and is easily seen in Koke'e and the Alaka'i. Although a decline was detected during the 1980's the species appears to have recovered and numbers seem stable at present. Populations were also found near Alexander Reservoir in the late 1990's/early 2000 and this is at a lower elevation than most birds are found and this may reflect a range expansion and show birds becoming more resistant to avian malaria. If this is the case then there is quite a large amount of lower elevation habitat which the species could occupy, including areas in the Mokolea Mountains, which is disjunct from the mountainous heart of the island. Listed as vulnerable by Mace-Lande, otherwise unlisted. The main threats to this species are disease, competition with alien species, habitat loss and predation by introduced rats and cats.
KAUA'I 'O'O (Moho braccatus)
Extinct. This species was last observed in 1987 when a single male was seen, although only two had been seen in the previous six years. The female of the pair disappeared after Hurricane Iwa. The threats which aided the species demise were habitat loss, disease and competition, although it appears that the small population just could not recover from large catastrophic natural disasters. The species has not been seen or heard since the male was last recorded, but a haunting recording of its song can be found on the Audubon recording Voices of Hawai'i's Birds.
KAUA'I O'U (Psitterostra psittacea)
Extinct. The last confirmed sighting of this species on Kaua'i was two seen in 1989 on a DOFAW survey. Despite predation from rats, natural disasters, food competition, disease and loss of habitat this was still one of the commonest endemic forest birds on Kaua'i into the late 1960's, the following catastrophic decline is unexplained but may have been aided by a new virulent strain of avian malaria. This species probably above all others shows the desperate need for information on disease and habitat loss (and protection) to prevent other seemingly "safe" species from becoming extinct. There is the very remote chance that there are a few surviving birds in the Alaka'i Swamp and a possible bird was heard calling in the late 1990's, but not since.
KAUA'I 'AMAKIHI (Hemignathus virens stejnegeri)
Kaua'i's second most abundant endemic forest bird species the 'Amakihi can be found easily above 2,000 feet in the Koke'e and Alaka'i areas, and may wander as low as 1,000 feet in Waimea Canyon and near Alexander Reservoir. Like the 'Elepaio there is suitable habitat in the Mokolea Mountains once the species become immune to avian malaria found at these lower elevations. The wild population has been estimated at 15,000-20,000 for the 1993 report and the population is stable or increasing ten years later. The threats to this species are much the same as other species on the island. A successful captive population exists for 'Amakihi, although all individuals have been collected on the Big Island, and as taxonomic research shows that Kaua'i's population is a separate species a further captive population should be considered.
'ANIANIAU (Hemignathus parvus)
The smallest endemic species on Kaua'i appears to be stable or slightly increasing in numbers and can easily be seen in Koke'e and particularly the Alaka'i. The 1993 estimate was 15,000-20,000 and this was roughly comparable with the estimate for 1981 and therefore this species appears to be holding its own against disease, predation, habitat loss and competition. There are currently none in captivity and with the population at its current level there does not seem to be an urgent reason for commencing one. Also known as Lesser 'Amakihi.
KAUA'I 'AKIALOA (Hemignathus procerus)
Extinct. Last observed in 1969 by P. Bruner, with the last specimen collected in 1960. Surveys between 1967 and 2000 have failed to locate any birds and it is presumed extinct. It seems unlikely that with the numerous surveys and the relative ease of identification that the species has been overlooked. Even in 1992 the species was listed as endangered by USFWS, despite not having been seen for almost 25 years.
KAUA'I NUKU-PU'U (Hemignathus lucidus hanapepe)
Extinct. The species has not been recorded reliably since 1987 when a single bird was seen by a survey team on two consecutive days. Later reports are either not reliable, refer to Kaua'i 'Amakihi or are not well documented. The cause decline of this species is unknown but was probably disease-related, rather than through habitat loss or predation/competition.
'AKIKIKI (Oreomystis bairdi)
The 'Akikiki or Kaua'i Creeper has declined in numbers quite considerably in the last 30 years and the current range of the species is much smaller than it was just fifteen years ago. In 1992 the species was estimated to be about 800 - 1,000 in number, and although numbers for 2002 are not known the species is certainly much harder to find and does not occupy habitat and areas where it was once quite regularly found. The species is now extremely uncommon in Koke'e National Park and one must venture further into the Alaka'i Swamp to observe it. Birds are still regularly reported along the Pihea Ridge Trail along the boardwalk where it joins the Alaka'i Swamp Trail. There are probably less than 700 individuals remaining.
'AKEKE'E (Loxops caeruleirostris)
A difficult species to survey as they tend to fly long distances across the forest between foraging sites. Numbers also seem to fluctuate greatly from year to year. In 1992 there were an estimated 5,100 individuals and the population appears to have remained at about the same level. Birds can often be seen along the Pihea Ridge Trail, by the Kalalau Overlook and along the Alaka'i Swamp Trail. The species is confined to forest over 3,500 feet in elevation and has not been recorded at the lower elevations of some other Kaua'i endemics ('Elepaio and 'Amakihi) and is perhaps more vulnerable to avian malaria than other species. Also known as the Kaua'i Akepa.
KAUA'I I'IWI (Vestiaria coccinea)
This species is generally restricted to forest above 3,000 feet, although is sometimes seen as low as 2,000 feet. This species seems to have the greatest population fluctuations from year to year (Melgar, 1998-2001) and the overall population may actually be declining. In 1992 the population was estimated at 10,000 - 20,000 and between 1968 and 1973 was estimated at 26,000 (+/- 6,000). Threats to the 'I'iwi include disease (the major threat), habitat loss, predation and competition. This species appears particularly susceptible to avian malaria, with most birds infected dying. Still present in good numbers in Koke'e and the Alaka'i and regularly observed at Kalalau Overlook, Pihea Ridge Trail, Alaka'i Swamp Trail and the forest to the southwest of Koke'e Museum.
KAUA'I 'APAPANE (Himatione sanguinea)
The most common Kaua'i endemic with an estimated population in 1992 of 100,000, a figure which is probably correct for 2002, although the species may have increased slightly in numbers during the intervening ten years. Commonly seen in all areas of the forest above 1,000 feet. Up to 40,000 birds reside in the Alaka'i alone. Although often recorded at lower elevations than the other forest endemics the species range appears to have remained the same, with few birds recorded away from traditional areas. The main threats to the 'Apapane on Kaua'i are habitat loss and disease, although the species appears to be becoming immune to some strains of avian malaria. Observable anywhere in Waimea Canyon State Park, Koke'e and the Alaka'i.
ESTIMATED NUMBER 1992
ESTIMATED NUMBER 2002
Island-wide in all habitats
Considered vulnerable. Both this and the Barn Owl are declining for unknown reasons.
0 - 10
Last seen in 1981 during USFWS survey. Unconfirmed reports in mid-1980's in Pihea/Alakai Swamp Trail
20 - 50
50 - 80+
Natural increase as well as re-introduction of captive bred birds in late 1990's has reversed the
downward trend of this species. Still listed as Critical.
20,000 - 30,000
Less than 20,000
Although still widespread and common, the species appears slightly less common, although this could
partly be due to birds moving into areas previously uninhabited, such as at lower elevations.
Extinct. Last recorded in 1985.
Presumed Extinct. Last recorded in 1981. Severe decline since 1960's when fairly common.
15,000 - 20,000
Same or Increase
Still the second most common endemic Kaua'i forest species. Numbers appear stable.
15,000 - 25,000
Appears to be maintaining its numbers.
Last seen in 1969.
0 - 10
Last seen in 1987. Reported later but no evidence.
800 - 1,000
Less than 1,000
The species appears to have declined in numbers and the area in which it occurs has shrunk.
Appears to be relatively stable in numbers.
10,000 - 20,000
10,000 - 20,000
Stable, perhaps slight decline.
Numbers appear stable, but annual fluctuations make assessing population difficult.
Kaua'i's most common endemic species. Numbers appear stable or slightly decreasing.
O'ahu's Endemic Forest Birds
PUEO (Asio flammeus sandwichensis)
This species is uncommon on O'ahu and the population is probably not much greater than the 200 estimated in 1992, and may in fact be smaller. Although there is no proof disease, poisoning and predation may have negative effects on the population.
O'AHU 'ELEPAIO (Chasiempis sandwichensis gayi)
This O'ahu endemic is decreasing in numbers and has been listed as critical by Mace-Lande, although remains unlisted by other conservation agencies in Hawai'i. The species may be classed as a full species in the future and this should help afford it more protection and money for research. The 1992 population was estimated at 200 - 500 birds and this figure may have slightly dropped in the following ten years. The species is divided into two populations with 20% being found in the Waianae Mountains and 80% in the Koolau Mountains. In the Honolulu area the species can be found at relatively low elevation, where it seems to have become immune to avian malaria. Unfortunately the population around honolulu appears to show a strong downward trend in the past 30 years, presumably through predation, disease, habitat loss and disturbance. The Kuli'ou'ou and Ka'alakei Valleys are probably the best spots to observe the species.
O'AHU 'AMAKIHI (Hemignathus virens chloris)
There appears to be a slight decline in the species numbers over the last ten years, although the population is still likely in the 50,000+ mark. The species is found in both the Waianae and Koolau Mountain ranges and can still be commonly seen in areas such as the Manan Trail and Aiea Loop/Ridge Trails. Although individuals of the Big Island form are kept in a captive breeding program it would be useful to ensure that some of the O'ahu form are also in such a program. The species uses non-native forest as well as native forest and appears to be moving into lower elevation areas and so the species may be becoming resilient against avian malaria.
O'AHU 'ALAUHIO (Paroreomyza maculata)
Probably Extinct. Once found in the Koolau and Waianae Mountains the species was last reliably recorded in 1978, with later reports in 1985 and 1990 considered questionable at best. The species can appear very similar to O'ahu 'Amakihi and so reports would ideally be supported with photographic evidence. The species previous stronghold was in the north Halawa Valley which was partly destroyed and widely disturbed during the construction of a new highway (the H-3) and so if the species survives it is now most likely to be away from this area.
O'AHU 'I'IWI (Vestiaria coccinea)
Extremely rare on O'ahu and almost extinct on this island. In 1992 the population was estimated at less than 50 individuals, most of which were in the Waianae Mountain range. Local birders have reported the species on very few occasions in the last 20 years, with only about two or three birds seen in the Koolau Mountains over that period. Why the species should become so rare on O'ahu is not really known but disease, habitat loss, pollution, predation, genetic inbreeding and competition must all play their part in the species demise. There are birds from the Big Island in captive breeding programs and so the future of the 'I'iwi on O'ahu may lie in individuals from other islands. Right: Adult 'I'iwi. Once one of the most common Hawaiian species the 'I'iwi is now extinct on Lana'i and Moloka'i and almost so on O'ahu.
O'AHU 'APAPANE (Himatione sanguinea)
Still fairly common on O'ahu with a 1992 population estimated at 20,000 - 50,000, although a decline has probably occurred in the last ten years. The species is often seen at lower elevations and may have developed some resistance to avian malaria and other diseases. The species can still be easily seen in the Koolau Mountains at such locations as the Aiea Ridge Trail and the Manana Trail.
ESTIMATED POPULATION 1992
ESTIMATED POPULATION 2002
Island-wide in all habitats.
Decline due to unknown reasons.
Upland and lowland forest.
200 - 500
Less than 400
Designated as critical. Birds in lowland areas particularly vulnerable.
Upland and lowland forest.
20,000 - 60,000
20,000 - 50,000
0 - 10
Last recorded in 1978; reported in 1990 but sighting tentative.
0 - 50
0 - 50
Critically endangered on O'ahu.
20,000 - 50,000
20,000 - 40,000
Maui's Endemic Forest Birds
PUEO (Asio flammeus sandwichensis)
This species is not widespread on Maui, despite the islands size and is probably due to the fact that Haleakala takes up almost the entire eastern portion of the island and therefore territories overlap or take in less than ideal habitat. In 1992 there were estimated to be 100 individuals and the population was considered to be declining. Ten years on and the population is probably about the same. Unidentified factors which have affected populations on other islands are also probably affecting the Maui population. More research is needed to identify the threats that the species faces.
BISHOP'S 'O'O (Moho bishopi)
Extinct. Last reliably observed in 1980, although unconfirmed reports into the mid-1980's and several 'O'o-like calls were heard by several people in 1985 during USFWS Surveys. The threats faced by this species are the same as for most other endemic forest birds - disease, habitat loss, disturbance, competition and inter-breeding. Despite the reported sightings there continues to be a question as to whether 'O'o's actually even existed on Maui!
MAUI PARROTBILL (Pseudonestor xanthophrys)
Listed as Endangered by several conservation groups the Maui Parrotbill was estimated to have a population in 1992 of <500 individuals, with a decrease in the population noted. In 2002 the species appears to still be declining slowly but may have slightly stabilised somewhat and the species is regularly observed in small numbers at the Waikamoi Preserve. The bulk of the population lives within the Hanawi Natural Area Reserve/East Maui Wilderness, and as access is severely restricted here the species may fare better than in publicly accessible locations. Birds have been banded and capture and recapture work has been carried out. The introduced Japanese Bush-Warbler may have an affect on the species. In 1980 there was just one detection of the Bush-Warbler, in 1992 the species was recorded at 66 of the stations, and the in 2000 the species was still increasing in numbers and range.
In 1999 biologists found a Parrotbill nest and translocated an egg to the Maui Bird Conservation Center at Olinda where the egg hatched, only the second chick of the species to be hatched in captivity, the other being a female which is being maintained at the Keauhou Bird Conservation Center on the Big Island.. The egg weighed 1.54 grams and the chick hatched during the third week of March.
Historic records show that the Parrotbill was once found in dry Koa forests on the northwest slopes of Haleakala but when most of this forest was cleared for timber, agriculture and cattle ranching the population was restricted to less-preferred wet 'Ohi'a forests. The species has been found in fossil records in dry lowland habitats on the north coast of Moloka'i but the species disappeared from that island shortly after the arrival of the early Polynesians, as a result of forest clearing and burning.
MAUI 'AMAKIHI (Hemignathus virens wilsoni)
This species is still common on Maui with 47,000 estimated in 1992 and with similar numbers present today, although a slight increase has been noted. The species is affected by the same threats as other endemic forest species, but it appears to be able to exist in non-native vegetation, for at least part of the time. There may be three genetically-distinct populations on the island, although all are located in west Maui. The species is no longer found in West Maui.
MAUI NUKU-PU'U (Hemignathus lucidus affinis)
Extinct. The species was last reliably recorded in 1989, although there were numerous reports between 1985 and 1986. The species was only found above 1600 metres and had a small habitat range in the Manawainui Valley. It is assumed that disease and the presence of alien species contributed to the species decline. Despite extensive bird surveys in the last ten years the species has not been observed again.
MAUI CREEPER (Paroreomyza montana newtoni)
This Maui endemic is still common in forest between 3,000 and 7,000 feet on the northwest and western slopes of Haleakala. In 1992 the population was estimated at 35,000 and there has been little change in the population since 1980. The species often utilises non-native vegetation, and at some locations such as Hosmer Grove may be found on the ground, in introduced trees and bushes and even in quite exposed windswept areas where there is little vegetation. No longer exists on West Maui and the decline there is unexplained but apparently preceded the appearance of the Japanese Bush-Warbler.
MAUI 'AKEPA (Loxops coccineus ochraceus)
Probably close to extinction on Maui, with the last confirmed sightings in 1980 when USFWS surveys reported two visual and one acoustic detections. Although the population was estimated at 230 in 1992 this was based on one acoustic detection in 1980 and had a variance of +/- 290. If any individuals do still remain they are in the East Maui Wilderness area, although almost daily work here would no doubt reveal the presence of any remaining birds. Disease, genetic factors, habitat loss, introduced species and natural catastrophes are all threats which face the species. It has also been reported that Parrotbill calls may be mistaken for 'Akepas and that the species may have become extinct in the early 1980's.
MAUI 'I'IWI (Vestiaria coccinea)
Two populations of this species have been known historically on Maui. The first was in West Maui, but this population was last recorded in 1980 when nine detections were made. The West Maui population was believed to be closer geographically to the Moloka'i population than the East Maui population. The West Maui population appears to be stable with numbers about the same as they were in 1992, approximately 19,000. The species is seldom found below 1,100 metres, presumably the present upper limit of mosquitoes as this species is severely affected by avian malaria. The 'I'iwi has become almost extinct on O'ahu and has declined severely on Moloka'i and is generally seen as a good indicator species for changes in Hawaiian birdlife and so a new survey of the Maui population should be carried out soon to estimate the health of Hawai'i's endemic forest birds.
CRESTED HONEYCREEPER (Palmeria dolei)
One of the most unusual plumaged birds in Hawai'i, the Crested Honeycreeper or 'Akohekohe is found on the northeast slope of Haleakala, Makawao forest reserve to Kaupo between 4,000 and 7,000 feet. the population in 1992 was estimated at 3,800 individuals (based on a 1981 survey), apparently the species has declined both in numbers and distribution since that time, although sightings in the 1990's show that the species may be increasing again. The 'Akohekohe can be seen regularly in the Waikamoi Preserve and very occasionally has been reported at Hosmer Grove. The species was once found in West Maui and on Moloka'i too, but is now extinct in those areas. The species can be very noisy and quite aggressive to other species and it is likely that disease, predation and habitat loss are the main threats to this species.
MAUI 'APAPANE (Himatione sanguinea)
Still a common and widespread species on East Maui between 2,000 and 8,000 feet. The population for East Maui appears to be stable with a population in excess of 90,000, mainly on Haleakala and the east Maui Wilderness. The West Maui population is declining severely and may soon disappear. There are seventeen birds in captivity in mainland zoos. The species appears to be able to deal with threats in the Hawaiian Islands better than other species and more information should be gathered as to why it is successful; perhaps the sheer numbers involved mean that loss to the population is "swallowed up" by the yearly recruitment?
PO'O-ULI (Melamprosops phaesoma)
Probably exinct as of 2004, but may still just hang on to existence. The species was only discovered in the 1970's but by 1992 the population was estimated at c.50 birds and by the end of the twentieth century just three individuals remained. Three birds were still in existence in 2001/2002 and comprised one male and two females. The species is found on the northeast slope of Haleakala from 5,000 to 6,000 feet in wet 'Ohi'a forest with dense understorey, where the species feeds. The presence of pigs and goats in its habitat which eat the low growing understorey vegetation results in its prime habitat being destroyed on a daily basis. Exclusion of these exotic species would help the species to recover if the population had been larger, but unfortunately it may be too late to reverse the trend. Other threats to the species include disease, genetic factors, predation (by rats and mongoose) and natural disasters such as hurricanes. If pigs and goats can be kept from destroying the understorey and if birds start nesting then there may yet be a glimmer of hope for the species.
In 2002 the three birds remaining in the Hanawi Natural Area Reserve in East Maui were subject to a new project to try to bring a pair together to instigate breeding. The three birds ranges do not overlap and so the birds do not encounter each other and thus chances of breeding success are zero. As a result of an Environmental Assessment written by the USFWS and the State DOFAW, as well as subsequent public comments, it was decided that it was the best strategy to translocate one of the females into the home range of the male, in the hope that they will breed and nest.
It has been shown with earlier translocations of Hawaiian birds that most individuals have a strong "homing instinct" and return to their original home range rather quickly, often within a few days. The plan for the Po'o-uli is to first catch the male and place a small radio transmitter on it so that it can be tracked and located and then catch the female and place her in the males home range when the male is nearby. If the two birds meet there is more chance that the pair will remain in the males territory.
During January 2002 ten trips had taken place to Hanawi but the bird team had been unable
to catch the male, despite observing him for three days in a row and the fact that he came within about twenty
yards of the mist nets. Poor weather during January 2002 also hindered efforts to help save the Po'o-uli. Even
if the project is successful it seems very likely that the Po'o-uli will become the next Hawaiian species to become
extinct. A full account of the Po'o-uli discovery, life history and population status can be found by clicking
on the following links: Po'o-uli, Po'ouli
2004, Po'ouli 2005.
New accounts will be updated or added with any new information received from 2005 onwards.
In 2003 efforts continued to capture the last remaining three birds known at that time and put them in a captive breeding program at San Diego Zoo, however this had not happened by the end of 2003 and only a single bird was observed three times during counts during the CBC week in the Hanawi Area. In September 2004 one female was captured and transferred to a captive breeding facility on Maui, however the bird died on November 28th. The other two individuals have not been relocated since and the species must now be considered extinct.
|SPECIES||RANGE||ESTIMATED POPULATION 1992||ESTIMATED POPULATION 2002||TREND||NOTES|
|PUEO||Island-wide in all habitats||100||100||Stable||No survey has been conducted.|
|BISHOP'S 'O'O||Upland forest||0||0||Extinct||Last reported 1980 but unconfirmed sightings in 1980's.|
|MAUI PARROTBILL||Upland forest||<500||c.500||Stable||Perhaps a slight increase.|
|MAUI 'AMAKIHI||upland forest||47,000||47,000||Stable||Slight increase in numbers.|
|MAUI NUKU-PU'U||Upland forest||<10||0||Probably Extinct.||Last recorded in 1989.|
|MAUI CREEPER||Upland forest||35,000||35,000||Stable|
|MAUI 'AKEPA||Upland forest||230||?||Decline, possibly extinct.||Last confirmed sighting in 1980.|
|MAUI 'I'IWI||Upland forest||19,180||19,000+||Stable||Extinct in West Maui, all remaining birds in East Maui.|
|CRESTED HONEYCREEPER||Upland forest||3,800||3,000+||Stable, perhaps slight decline.||Declined during mid-1980's although this trend appears to have been reversed in the 1990's.|
|MAUI 'APAPANE||Upland forest in both West and East Maui||112,000||100,000+||Stable, perhpas declining in West Maui.|
|PO'O-ULI||Upland forest||<50||3||Severe decline||Just three birds, one male and two females survived in 2002. Probably no birds survive as of 1/12/2004.|
Moloka'i's Endemic Forest Birds
PUEO (Asio flammeus sandwichensis)
Although there has never been a proper survey the population was estimated at 100 individuals in 1992. The population is probably stable or declining today as habitat is lost and other unknown factors take effect, as they are on Pueo on other islands. More research is needed to estimate the current population and threats faced by it.
MOLOKA'I OLOMA'O (Myadestes lanaiensis rutha)
Extinct. The species was last sighted in 1988, with the most recent reports before that in 1979, when three were seen in Olokui and three were seen in Kamakou, and three seen in 1974. The species was restricted to the Olokui Plateau between 900 and 1500 metres, but habitat loss, disease, genetic factors and competition and predation finally took their toll. A second subspecies M.l. lanaiensis is also now extinct. The Japanese Bush-Warbler, an introduced species, is now widespread and common on Moloka'i, even into the higher elevations, whereas when the Oloma'o was still present there were none or just a few Bush-Warblers present. The threat posed by this introduced species needs to be examined thoroughly.
MOLOKA'I 'AMAKIHI (Hemignathus virens wilsoni)
The species still numbers 1500 plus today but the species is declining on Moloka'i. The population in 1992 was approximately 1800 individuals. The usual factors of disease, competition, predation, habitat loss and natural disasters are all having an effect on the species. The Japanese Bush-Warbler may pose a serious threat.
MOLOKA'I CREEPER (Paroreomyza flammea)
Extinct. the species was last recorded in 1963 when a single bird was observed. The most recent previous sighting to that was of three birds in 1962 and two birds in 1961. The species has not been surveyed for since 1988. Apparently the bird seen in 1963 was on the west rim of Pelekunu Valley on Ohialele Plateau and was a bright orange plumaged individual which vocalised a lot and readily approached humans. Presumably the same threat factors were present for this species as they are for all other Hawaiian endemic forest species.
MOLOKA'I 'I'IWI (Vestiaria coccinea)
As on O'ahu this species has declined severely on Moloka'i and is probably extinct here, although a few may remain undetected. There was an estimated population of 50 birds or less in 1992, based on a 1988 survey which showed ten records. The widespread occurrence of mosquitoes on Moloka'i presumably has aided the species decline.
MOLOKA'I 'APAPANE (Himatione sanguinea)
The population was estimated at c.39,000 in 1992 and although the species is still widespread a slight decline in numbers has been estimated in recent years. The species is restricted to East Moloka'i (like the other forest endemics except the Pueo) and disease, predation, habitat loss and competition are the main threats yet again.
|SPECIES||RANGE||ESTIMATED POPULATION 1992||ESTIMATED POPULATION 2002||TREND||NOTES|
|PUEO||Island-wide in all habitats||100||100||Stable||No survey conducted|
|MOLOKA'I OLOMA'O||Upland forest||0 - 10||0||Extinct. Decline.||Last reported in 1988.|
|MOLOKA'I 'AMAKIHI||Upland forest||1800||1800 or less||Decline||1992 survey +/- 700 therefore exact change unknown but appears to be declining.|
|MOLOKA'I CREEPER||Upland forest||0||0||Extinct||Last reported 1963.|
|MOLOKA'I 'I'IWI||Upland forest||<50||0||Extinct. Decline.||Very few reported since 1988 and presumed extinct since c. 1997.|
|MOLOKA'I 'APAPANE||Upland forest||39,000||<39,000||Decline||Decline due to mosquito infestation and habitat loss.|
Lana'i's Endemic Forest Birds
PUEO (Asio flammeus sandwichensis)
The population is probably declining on Lana'i and although there has never been a survey the 1992 estimate of 50 individuals (+/- 25) is probably about right. There is not a great deal of habitat on Lana'i and the increase in alteration of habitat on the island has probably not helped the species. More research is needed into the needs of this species.
LANA'I 'AMAKIHI (Hemignathus virens wilsoni)
Extinct. The species was last recorded on the island in 1976. The Hawaiian Forest Bird CAMP comments that the extinction may have been due to malathion which had been used to eradicate fruitflies on the island by the Dole Corporation, although other factors such as disease, genetic factors, competition, habitat loss and natural phenomena would also have played a part, at least in earlier years before the spraying of chemicals.
LANA'I 'APAPANE (Himatione sanguinea)
As with the last species the species may have declined due to the use of malathion and resultant poisoning. Surveying for birds on Lana'i is also difficult due to the vertical terrain in the species habitat, however massive loss of habitat on the island probably means that this species will only survive in extremely small numbers or will disappear altogether within the next few years. All habitat on the island is within the "mosquito zone" and so disease is probably the major limiting factor to (any endemic) species success.
|SPECIES||RANGE||ESTIMATED POPULATION 1992||ESTIMATED POPULATION 2002||TREND||NOTES|
|PUEO||Island-wide in all habitats||50 +/- 25||<50||Probable Decline||No survey conducted.|
|LANA'I 'AMAKIHI||Upland forest||0||0||Extinct||Last recorded in 1976.|
|LANA'I 'APAPANE||Upland forest||<100||<100||Decline||Decline due to mosquito infestation and habitat loss.|
Hawai'i's Endemic Forest Birds
'IO (Buteo solitarius)
This species, the only endemic raptor in Hawai'i, is found island-wide from sea-level up to 9,500 feet. The species is currently considered stable with a population of up to 2,500 individuals. The species is at threat from shooting, disturbance, indirect poisoning, breeding habitat loss, predation and possibly by aircraft disturbance. Although the species main habitat is forest and higher elevation areas the species is frequently observed at sea level and in human-modified habitat. The species was reported as occurring less frequently in the Kailua-Kona area in the 1980's and 1990's but several pairs can be seen along the western and southwestern coasts of the Big Island from Kailua-Kona to South Kona. The species also unfortunately predates 'Alala, Hawai'i's second rarest species. Also known as the Hawaiian Hawk.
PUEO (Asio flammeus sandwichensis)
The estimated population for this species on the Big Island in 1992 was a maximum of 2,000 birds, and although there are periodic die-offs the species currently appears to be stable and can be seen quite commonly island-wide. Threats on this island are the same as for other Hawaiian Islands but also include shooting and predation by the Hawaiian Hawk ('Io).
'ALALA (Corvus hawaiiensis)
Hawai'i's only extant crow species is critically endangered and now numbers only c.10 birds, all of which are in captivity, the last mated pair in the wild not being seen since 2002. The species is only found in the central Kona area near McCandless Ranch and the range is less than 200 square kilometre. There are occasional reports from Kau and Kapapala forests, including a recent unconfirmed sighting in 2002 by visiting birdwatchers. Although birds are kept in a captive breeding program the species nests rarely in captivity, apparently due to the old age of the birds in the population. Young birds which had been reared in the program and released into the wild were usually either killed by 'Io or rats/mongoose or disappeared from the release site never to be recorded again, although presumably they also perished. The species is at severe threat from predation, genetic factors, population age, disease, natural catastrophes, human interference and disturbance (including shooting), loss of habitat and competition from introduced species. Individuals formerly seen on the McCandless ranch were not observed during 1999-2001 and it must be that they have died. If the fortunes of this species do not change soon the species will undoubtedly become extinct within ten years. The 2004 IUCN Red List considers the species to be extinct in the wild.
OMA'O (Myadestes obscurus)
A still widespread and numerous species and often found at lower levels in areas where there is avian malaria, although its island-wide range has contracted in the past twenty years and is no longer found in areas such as Kohala, montane Kona or Hualalai. The population is probably stable, although declines in some areas have been observed. Threats to this species include predation, disease, habitat loss and competition, however the species should be closely and carefully researched and monitored to find reasons why this species appears to be doing so well despite much of its habitat being in easily accessible locations (such as Thurston lava Tube); the information gained may help in protecting the Puaiohi on Kaua'i and any other Hawaiian Thrush which may possibly be refound.
HAWAI'I 'ELEPAIO (Chasiempis sandwichensis)
Three sub-species occur on the Big Island - sandwichensis, bryani and ridgewayi. The species may be declining slightly in numbers although the 1992 estimate of 207,000 has probably not changed a great deal. Population fluctuations are recorded with some regularity. Although the population is quite high, individual populations are at risk from any number of threats such as habitat loss and predation. Disease is probably less of a threat to 'Elepaio than it is to many other endemic forest species.
HAWAI'I 'O'U (Psittirostra psittacea)
Presumed Extinct. Last sighted in 1986 and none were located in an extensive search in 1987, although it was possibly heard in 1988. As for the Kaua'i 'O'u this species was once widespread and common, even well into the twentieth century and so if the species were to be rediscovered immediate plans should be made for captive propagation or intensive research. Disease, introduced species and habitat loss are the prime factors in the species decline, although it is not known to what extent each factor played in the species decline. Lava flows from the Kilauea caldera went right through the species main stronghold in the 1980's and the resultant habitat loss no doubt played an extremely large part in the species disappearance.
PALILA (Loxoides bailleui)
This species is restricted to the Mamane forest on Mauna Kea between 6478 and 9360 feet elevation. Threats to the species include population fluctuations, drought, fire, disease, habitat loss and predation. For many years grazing by introduced species such as goats and deer resulted in massive habitat loss and lack of new trees in the heart of the species range. Only after a lengthy legal process were these animals removed and the habitat protected. Although the species has still probably declined since 1992, the removal of at least one of the aforementioned threats should help in reversing the trend. Today Pu'u La'au is the best location to observe this species and although they can be elusive and quiet a little perseverance should result in a sighting.
HAWAI'I 'AMAKIHI (Hemignathus virens virens)
This species is still widespread and common on Hawai'i and the 1992 population estimate was 870,000 and the species appears stable today. There is a captive population of about thirty birds. Threats to this species are the same as for other species mentioned beforehand. the species is easily seen at locations such as Pu'u La'au, Hakalau NWR, Volcanoes National Park and Manuka State Park.
AKIAPOLA'AU (Hemignathus munroi)
One of the jewels of Hawaiian birding, the Akiapola'au is restricted to windward Koa forest between 4,500 and 9,000 feet. The windward Mauna Kea population is apparently declining, the leeward Kona population has more or less disappeared and the population at Pu'u La'au supposedly consists of males only. The 1992 estimate of 1,500 individuals is probably an overestimate and the population today is probably less than 1,000 birds. The species faces the same threats as other Hawaiian forest birds and is not a good candidate for captive breeding programs due to its specialised feeding techniques and bill structure. Birds are best observed at Hakalau, Kipukas off the saddle Road and Pu'u La'au.
HAWAI'I CREEPER (Oreomystis mana)
Found only on the Big island between 4,000 and 6,500 feet, with sub-populations in the windward forest, Kau, south Kona and Hulalai. the 1992 population estimate of 12,500 is probably still correct. The species can be hard to observe in many areas. Threats to the species are as those for other Hawaiian forest species. there are currently no birds in captive breeding programs.
HAWAI'I AKEPA (Loxops coccineus coccineus)
The 1992 population was estimated at 14,000 and although the species is still common at some locations, such as Hakalau NWR, the species appears to be declining, both in numbers and distribution. Recently the species has been found more at the higher elevation locations and is an increasingly rare sight below about 5,000 feet. There are four sub-populations and inbreeding may be a significant factor in the smaller subpopulations. Disease, competition, predation and habitat loss and modification are all further threats. There are currently none in captive breeding programs.
HAWAI'I 'I'IWI (Vestiaria coccinea)
The population is considered to be declining on the Big Island, although it is uncertain how many fewer birds there are than were estimated in 1992, when the population was considered to be about 340,000 individuals. the species tends to move slowly up and down the elevation gradient and so it is vulnerable to many threats such as disease, competition, habitat loss and predation. The species range has contracted, with birds previously found as low as 3,000 feet, but with none now lower than 4,000 feet. The birds range as high as 9,000 feet. There are at least twenty-five birds in captivity, which may be useful in finding treatments for the eradication of avian malaria, as well as providing a base population for captive breeding.
HAWAI'I 'APAPANE (Himatione sanguinea)
Widespread and abundant. This species numbers have not changed much in the last ten years and so the 1992 population estimate of 1000,000 birds is probably quite reliable. About thirty are in captive programs at present. Subject to the same threats as other endemic forest species but more resistant to avian diseases and often found at lower elevations. The large population on this island should mean the species should maintain its levels for a long time and the species should be studied to provide information that may be useful on other smaller populations of 'Apapane, as well as for rarer species.
ESTIMATED POPULATION 1992
ESTIMATED POPULATION 2002
Island-wide in various habitats
1,400 - 2,500
1,400 - 2,500
Island-wide in various habitats
Stable - Declining
Occasional unexplained die-offs.
10 all in captivity.
Critical. Population is old and breeding is very infrequent. Predation by 'Io kills many new young
Population fluctuates but general downward trend.
Possibly slightly Declining.
Three separate populations exist.
Last sighted in 1986, last possibly heard in 1988.
1317 - 6400
c.3000 - 5300
Decline due to loss of habitat through grazing animals, slight reversal of fortune since mid-1990's.
Population estimates are probably overestimates.
Species range may have decreased.
Species range appears to have contracted.
Population disperses widely.
The most abundant endemic bird in the Hawaiian Islands.
The 'Apapane (Himatione sanguinea). Hawai'i's most abundant endemic bird is
still a common sight in higher elevation forests in the Main Islands.
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PYLE, R.L. 1990. Native breeding birds of Hawaii. 'Elepaio 50 (12):99-100.
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SCOTT, J.M., S. MOUNTAINSPRING, F.L. RAMSEY and C.B. KEPLER. . 1986. Forest Bird Communities of the Hawaiian Islands: Their Dynamics, Ecology and Conservation. Studies in Avian Biology #9. Allen Press, Kansas.
Christian Melgar. Worthing, West Sussex, UK. 2002 (with minor updates 2005).