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Thomas J. Snetsinger

Publications and source records attributed to Thomas J. Snetsinger.

7 recordsLinked to original sources
USGS2005

Breeding ecology of the Puaiohi (Myadestes palmeri)

We studied the breeding ecology of the critically endangered Puaiohi ( Myadestes palmeri ), a poorly known Hawaiian thrush endemic to the island of Kauai. From 1996 through 1998, we monitored 96 active nests over the course of three breeding seasons. Mean clutch size was 2.0, and pairs produced an average of 1.5 fledglings/successful nest. Pairs renested after failure and some raised multiple broods. The mean annual reproductive effort was 2.1 nesting attempts/territory, and pairs produced a mean 1.1 fledglings/attempt. Large differences in nesting effort and productivity occurred among years, with mean number of fledglings/territory ranging from 0.4 to 4.9. Predation by owls (probably Short-eared Owls, Asio flammeus ) and introduced rats (probably black rats, Rattus rattus ) accounted for most nest failures. The presence of non-breeding floaters in the population and their largely unsuccessful attempts to gain territories in the study area suggest that the population is near carrying capacity. The high reproductive potential of the Puaiohi may help explain its persistence despite the species' historical rarity.

Hawaii↗
USGS2001

What caused the population decline of the Bridled White-eye on Rota, Mariana Islands?

The Bridled White-eye ( Zosterops conspicillatus rotensis ) was Once thought to be common and widespread on Rota, Commonwealth of the Northern Mariana Islands, but is now restricted to several patches of native limestone forest in and adjacent to the Sabana region. Surveys conducted in 1990 indicated that the population had declined by 87% between 1982 and 1990 for unknown reasons. The low density and restricted habitat association of the Bridled White-eye on Rota contrasts with the situation on Saipan, Tinian, Agiguan, and formerly on Guam, where the Bridled White-eye is the most common forest bird and occurs at all elevations and in all habitat types. We surveyed the entire range of the Rota Bridled White-eye in 1996 to estimate its current numbers and distribution. We also reviewed existing information on the white-eye and evaluated potential causes of its decline, including predation by Black Drongos ( Dicrurus macrocercus ), rats ( Rattus spp.), and the brown tree snake Boiga irregularis ); pesticides; avian disease; and habitat loss and alteration. We found that 94% of the extant population of 1,165 white-eyes on Rota was restricted to four patches of old-growth, native limestone forest covering only 259 ha. We believe that the population decline and current localized distribution is primarily a result of habitat changes due to agricultural development and typhoons, but the absence of white-eyes from several stands of native forest above 200 m remains unexplained. The Rota white-eye may be a different species from white-eyes found on Saipan, Tinian, Agiguan, and Guam, with different habitat preferences.

Rota↗
USGS2001

The Hawai'i rare bird search 1994-1996

We compiled the recent history of sightings and searched for 13 rare and missing Hawaiian forest birds to update status and distribution information. We made 23 expeditions between August 1994 and April 1996 on the islands of Hawai‘i, Maui, Moloka‘i, and Kaua‘i totaling 1,685 search hours, 146 field days, and 553 person days. During our surveys we found four critically endangered birds: the Po‘ouli ( Melamprusops phaeosoma , five to six individuals), Maui Nukupu‘u ( Hemignathus lucidus affinis , one individual), ‘I‘iwi ( Vestiaria coccinea ) on Moloka‘i (one individual), and the Puaiohi ( Myadestes palmeri , 55-70 individuals). Detection rates for each species were 0.013, 0.002, 0.012, and 0.318 detections/hr, respectively. Although not visually confirmed during our surveys, auditory detections, unconfirmed sightings, and other reports suggest the possible existence of ‘O‘u ( Psittirostra psittacea ) on Hawai‘i, Kaua‘i Nukupu‘u ( Hemignathus lucidus hanapepe ), and Maui ‘Akepa ( Loxops coccineus ochraceus ) in perilously low numbers. Six undetected forest bird populations, Kama‘o ( Myadestes myudestinus ), Kaua‘i ‘O‘o ( Moho braccatus ), Bishop’s ‘O‘o ( Moho bishopi ), ‘O‘o on Kaua‘i, Greater ‘Akialoa ( Hemignafhus ellisianus ), and Kakawahie ( Paroveomyza flammea ) have high probabilities of being extinct. Oloma‘o ( Myadestes lanaiensis ) from Moloka‘i are probably extirpated from the areas searched on that island but may persist on the unsurveyed Oloku‘i Plateau.

Hawai'i↗
USGS1998

Ou ( Psittirostra psittacea )

The ‘Ö‘ü and the Läna‘i Hookbill are plump, predominantly olive green, thick-billed Hawaiian honeycreepers. The ‘Ö‘ü is now very rare and restricted to remote, high-elevation native forest, and the Läna‘i Hookbill is extinct. They are closely related species, belonging to a specialized tribe, Psittirostrini, consisting of nine historically known Hawaiian species with heavy, finchlike to parrotlike bills. Because of their taxonomic affinity and the paucity of information on the Läna‘i Hookbill, we are treating the two species in a single account.

Birds of North America↗
USGS1997

Translocation of the Palila, an endangered Hawaiian honeycreeper

The Palila Loxioides bailleui is an endangered Hawaiian honeycreeper that is restricted to high-elevation dry woodlands on Mauna Kea volcano, Hawaii. Palila are absent or occur in small numbers throughout most of their historic range because of habitat loss, predation and avian disease. The Palila's habitat is regenerating as a result of feral ungulate control, but the species is likely to be slow in recolonizing former ranges because of strong site tenacity. In March 1993, we translocated 35 Palila to Kanakaleonui on the eastern slope of Mauna Kea to determine whether we could speed recovery by releasing adult birds in new areas where predators were controlled. At least two pairs of translocated Palila successfully nested at the release site during their first breeding season, and two other pairs constructed nests. The density of Palila at Kanakaleonui in the three years following the translocation was higher than that before translocation. Approximately half of the translocated birds remained at the release site for 2?6 weeks and then homed back to their capture site, >20 km away. Translocations of adult birds and release of captive-reared juvenile Palila, in combination with additional habitat restoration, may be an effective management tool for speeding the recovery of this species.

Pacific Conservation Biology↗
USGS1997

Kauai's endangered solitaires: Update on population status and distribution 1996

The puaioihi ( Myadestes palmeri ) and the kamao ( M. myadestinus ) are endangered solitaires endemic to Kauai in the Hawaiian Islands and now restricted to the Alakai Swamp. The puaiohi has been rare historically with population estimates declining since the first population surveys 1968-73. Puaiohi were believed to be on the verge of extinction with population estimates less than 35 birds since 1981. In 1995 intensive studies of the breeding biology and population status of the puaiohi began using mist netting, color banding, spot mapping, and surveys. Fifty active nests were discovered and 63-75 birds monitored at the Koaie study site. Seven survey expeditions in 1996 detected 55-70 more puaiohi from 6 of 8 main river drainages of four survey areas explored. Although still rare and vulnerable to extinction (145±19 individuals known), puaiohi are more widely distributed within the Alakai Swamp than previously believed. Our data from 1996 suggest previous surveys methods have underestimated the population size or that the population has increased since 1981. The kamao has not been confirmed since 1985, but unconfirmed reports were made from 1989-1996. We have not sighted kamao to date despite intensive search efforts. We infer from detection probabilities that the species in highly likely to be extinct.

Hawaii↗