7—
FINDINGS AND RECOMMENDATIONS

Chapters 2 through 4 describe what is known about the 'Alala, and Chapter 5 describes relevant precedents for active management of other endangered species. Chapter 6 describes in detail options for the joint management of the wild and captive populations of 'Alala. Having examined the available data and studied the experiences of others working with endangered avifauna, we now offer a summary of what has occurred to date and some recommendations for action. It is imperative to build on what is already known about the 'Alala and other species if we are to make informed decisions about recovery and management actions.

The Wild Population

Findings

The 'Alala—an omnivorous, but primarily frugivorous, forest-inhabiting corvid that differs in those respects from the widespread and familiar crows of the larger continents—is near extinction. Its decline is part of a larger phenomenon: reduction and extinction of forest birds, especially frugivores, that have been associated with human colonization throughout Polynesia.

As of January 1992, the 'Alala continues to exist on the McCandless Ranch, which are present in two and possibly three territories. A count in March and April 1992 located 11 birds. A few additional 'Alala might persist elsewhere on the Kona Coast north of the McCandless Ranch, and perhaps within the Ka'u District, but no other breeding population is likely to exist.

In the last 14 years, death rates of adult 'Alala in the wild were inordinately high, except at the McCandless Ranch, where numbers of 'Alala observed appear not to have changed since 1976. We do not know why adult survivorship has been low or why it has been higher at McCandless than at other sites, but this fact alone can account for the disappearance of 'Alala from two areas (Hualalai and Honaunau).

Limited banding data and census efforts in the Kona District during the 1970s and 1980s indicate that during this period of precipitous decline, clutch size for the 'Alala is at the low end of what has been found to be typical of that of other Corvus species; nesting pairs of 'Alala continued to produce fledglings at the McCandless Ranch at rates slightly lower than those of other corvids, and even lower elsewhere; and juvenile survival (up to 1 year) in the Kona District was comparable to that of other corvid species that are not endangered.



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Scientific Bases for the Preservation of the Hawaiian Crow 7— FINDINGS AND RECOMMENDATIONS Chapters 2 through 4 describe what is known about the 'Alala, and Chapter 5 describes relevant precedents for active management of other endangered species. Chapter 6 describes in detail options for the joint management of the wild and captive populations of 'Alala. Having examined the available data and studied the experiences of others working with endangered avifauna, we now offer a summary of what has occurred to date and some recommendations for action. It is imperative to build on what is already known about the 'Alala and other species if we are to make informed decisions about recovery and management actions. The Wild Population Findings The 'Alala—an omnivorous, but primarily frugivorous, forest-inhabiting corvid that differs in those respects from the widespread and familiar crows of the larger continents—is near extinction. Its decline is part of a larger phenomenon: reduction and extinction of forest birds, especially frugivores, that have been associated with human colonization throughout Polynesia. As of January 1992, the 'Alala continues to exist on the McCandless Ranch, which are present in two and possibly three territories. A count in March and April 1992 located 11 birds. A few additional 'Alala might persist elsewhere on the Kona Coast north of the McCandless Ranch, and perhaps within the Ka'u District, but no other breeding population is likely to exist. In the last 14 years, death rates of adult 'Alala in the wild were inordinately high, except at the McCandless Ranch, where numbers of 'Alala observed appear not to have changed since 1976. We do not know why adult survivorship has been low or why it has been higher at McCandless than at other sites, but this fact alone can account for the disappearance of 'Alala from two areas (Hualalai and Honaunau). Limited banding data and census efforts in the Kona District during the 1970s and 1980s indicate that during this period of precipitous decline, clutch size for the 'Alala is at the low end of what has been found to be typical of that of other Corvus species; nesting pairs of 'Alala continued to produce fledglings at the McCandless Ranch at rates slightly lower than those of other corvids, and even lower elsewhere; and juvenile survival (up to 1 year) in the Kona District was comparable to that of other corvid species that are not endangered.

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Scientific Bases for the Preservation of the Hawaiian Crow Although extensive field studies have been conducted, many aspects of the behavior and biology of the 'Alala are still poorly understood, and no single cause for the decline in the wild 'Alala population can be identified. However, previous studies implicated habitat and food, predators, and diseases and parasites. When populations are as small as this one, demographic accidents and random environmental disturbances are likely to cause extinction. Clearly, a dominant cause of the decline has been alteration of the 'Alala habitat throughout its historical range as a result of grazing by ungulates, logging, and agriculture in the mid-elevation belt (1,000–1,800 m). The magnitude of mortality caused directly by collecting and shooting is difficult to know, but it has probably been substantial, even in recent decades. Furthermore, introduced roof rats prey on eggs and nestlings, and introduced mongooses prey on fledglings on the ground. Two introduced diseases that are widespread among native birds and affect the 'Alala are avian malaria and avian pox. The number of crows that would constitute a minimum viable population for long-term survival of the species cannot be estimated reliably at this time. But it can be said that the species will be in danger of extinction for the foreseeable future. The committee is unanimous in believing that without an active management program the 'Alala population on the McCandless Ranch is likely to become extinct in 1–2 decades from chance, genetic, or demographic events. Maintaining a Wild Population Recommendation 1: In light of what is known about the 'Alala, a viable wild population should be established and maintained. The current size of the population in the wild must be increased for demographic and genetic security. Considering how few crows remain, it is advisable to manage the wild and captive populations as a single unit. Such joint management will require that the identity of all existing birds be known. The possibility that additional birds survive on public and private lands in Hualalai and the Ka'u District needs to be investigated by the U.S. Fish and Wildlife Service and the state of Hawai'i, because additional birds would be potentially crucial to species recovery. They could provide critical, traditional experience for newly released, naive 'Alala being reintroduced into formerly occupied territories. However, contingency plans for the wild population must be developed in the event that the strategy proposed above fails. While the wild population must be maintained if at all possible, there might come a time when it would be necessary to remove all birds from the wild

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Scientific Bases for the Preservation of the Hawaiian Crow and put them in captivity (Option 2). This option should be considered only under the following circumstances: 1) when the wild population is known to be less than two breeding pairs for two consecutive years, and 2) state-of-the-art breeding facilities exist on the Hawaiian islands and the captive population is reproducing well. Recovery Team Recommendation 2: A new recovery team or advisory working group for the 'Alala should be established. The federal Alala Recovery Plan (Burr et al., 1982) and the state Alala Restoration Plan (Burr, 1984) are admirable documents that contain concise summaries of the history and status of the species and sound recommendations for recovery. Each places priority on the protection and restoration of native habitat, the study of disease, and predator control, and each recommends an integrated management of the captive and wild populations. The federal plan designates critical habitat that needs protection and the state plan sets priorities for incorporating that land into a conservation scheme. In the decade since the federal plan was issued, however, it has not been implemented, and the 'Alala has declined further. The committee recommends establishing a new recovery team or advisory working group for the 'Alala that includes state and federal biologists; other professional biologists who are experts in ecology, captive propagation, reintroduction, population biology of birds, and population genetics; an avian veterinary pathologist; an aviculturist; a corvid specialist; and a representative of the private sector, preferably a private land-owner or land manager. This combination of experts will provide the knowledge and skills necessary for joint management of the wild and captive populations. The recovery team must monitor the progress of the 'Alala's recovery and identify research priorities. Land Management Recommendation 3: For the 'Alala, as for other endangered species in Hawai'i and elsewhere, habitat restoration and maintenance are of paramount importance for species recovery and sustainability. Efforts to control and counteract the impacts of exotic animal and plant species must be given high priority. In other habitats along the Kona coast where the 'Alala has already been extirpated, numerous endemic bird populations are declining. Unless the causative factors are identified and corrected, preservation efforts for the 'Alala will be seriously compromised.

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Scientific Bases for the Preservation of the Hawaiian Crow Habitat preservation Recommendation 4: The committee strongly urges the state of Hawai'i and the U.S. Fish and Wildlife Service to establish one or more new preserves along the Kona coast. Acquisition, restoration, and proper management of a significant, dedicated ecosystem preserve on the Kona slope is important for the continued existence of 'Alala in the wild. As discussed in Chapter 2, little pristine forest habitat exists anywhere in the Kona District. The forested slopes of the Kona District constitute one of the most important centers of endemism in the entire Hawaiian Islands chain. Despite its enormous biological significance, the Kona District lacks a habitat preserve that is dedicated to and managed for the native habitat. The absence of a dedicated forest preserve in Kona is especially problematic if the 'Alala or any other endangered species is to be reintroduced. One cannot justify the release of captive-reared birds into areas where the native population has been extirpated and where there is no plan for substantial improvement in the long-term management of the native ecosystem. At best, it would effectively doom any reintroduction program to producing an expensive repetition of the original extirpation events. At worst, it would cause the program to fail to re-establish any reproducing population. For purposes of 'Alala recovery, the recommended preserve should be as close as possible to the McCandless Ranch and should contain areas of forest both at the nesting elevations (1,200–1,800 m) and in the feeding zones (especially down to 800 m in moist 'ohi'a forest). Recommendation 5: The committee strongly recommends that state and federal agencies and private land-owners develop a program of cooperative agreements, easements, and modes of direct compensation to promote a system of exclosures of various sizes and locations. It also recommends that such a program include other creative manipulations of the habitat to protect habitat patches on ranches from the impacts of cattle and other herbivores, so as to restore and maintain the essential features of crow habitat in sufficient quantity and quality for viable populations of crows and other native species of plants and animals to be secure for the indefinite future. During the 'Alala's recovery period, the cooperation of ranches in the vicinity of the remnant wild population will be vital. Research on the specific behavioral use of these properties by 'Alala will provide much needed insight into how cattle and 'Alala can coexist elsewhere along the Kona slopes. If the state or federal government can acquire a large tract of land for a dedicated Kona coast ecosystem, as recommended above, then it could function, in concert with a system of exclosures on surrounding ranch lands, as a reservoir from which species could disperse into peripheral habitats.

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Scientific Bases for the Preservation of the Hawaiian Crow Cattle ranching Recommendation 6: The committee encourages the economical management of cattle ranches in ways that provide critical habitat for native flora and fauna. Ranches that incorporate a holistic perspective abound throughout North America and are increasing there and in other parts of the world, e.g., Africa, South America, and Australia. Because ranches are large, and therefore can contain larger stands of native or near-native habitat, they make vital contributions to the long-term protection of landscapes and ecosystems, as long as they are managed in a benign, self-sustaining way with a multiple-use approach, and are not exploited for maximum short-term financial gain. Recovery and long-term survival of 'Alala through extensive portions of its native range depend on the good will and interest of the cattle-ranching community, which can be obtained only if ranchers understand how the economic goals of food production and healthy natural forest management can be met simultaneously. Ranchers often know and understand the natural history of their properties extremely well, in part because they spend considerable time attending to the annual cycle of their landscape and animals. Property-owners involved with ranching operations usually are justifiably proud and fond of the natural attributes of their land. These persons need to be respected, listened to, and encouraged to participate fully in the process of understanding and protecting endangered species, such as 'Alala, and their habitats and ecosystems. Four features of habitats, as set forth below, are crucial to the 'Alala. All four can be maintained in good quantity on cattle ranches. If property-managers control or prevent clearing and grazing in critical areas of sufficient size and distribution, 'Alala territories ought to be able to persist indefinitely in cattle-ranch settings on the Kona slopes. Tall trees and forest patches. 'Alala was always a forest-inhabiting crow with the habits of roosting, resting, displaying, and nesting in tall trees. 'Alala will live in forested areas that are interspersed with openings, pastures, occasional clear-cuts, and selective tree removals. 'Alala will not live in areas that have lost their essential forest stature. Mature 'ohi'a and emergent koa must exist in dense stands covering tens to hundreds of hectares. Numerous smaller wood lots widely dispersed and connected by corridors might be better than one or a few extensive stands. Native fruit. 'Alala consume a wide variety of fruits all year round and even feed them extensively to dependent young. Especially important traditional fruits include: 'ie'ie, mamaki, 'olapa, 'oha, ho'awa, and pilo. They and many other native fruits grow on shrubs, small trees, and vines. Quantities of those plants must be protected from clearing and grazing to provide feeding habitat for 'Alala. Moreover, the plants produce fruit for only part of the year, so 'Alala requires adequate supplies of diverse native food plants to prevent critical nutrient shortages during any season. In some small key areas (e.g., areas with certain fruiting

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Scientific Bases for the Preservation of the Hawaiian Crow shrubs), creative horticulture could be employed to re-establish populations of these plants in areas occupied by cattle and other ungulate herbivores by growing them as epiphytes in artificial planters suspended in trees above the heads of the livestock. Understory vegetation. Although often seen in the forest canopy, 'Alala regularly forage within several meters of the ground (Sakai et al., 1986), and fledgling 'Alala depend on understory and ground cover to shelter them from predators for several weeks following fledging. Native understory can be maintained only by excluding cattle and other grazing or rooting mammals. Maintenance of large examples of such terrain interspersed throughout a ranch property is especially critical for 'Alala nesting. Habitat corridors. 'Alala prefer forest and forest-edge habitats and will disperse more readily when provided unbroken habitat corridors. In a ranch setting, these can be maintained efficiently by excluding cattle from networks of forest corridors along fencerows, road margins, and natural forest-edge ecotones. It is especially vital that corridors of native 'ohi'a-koa forest be allowed to regenerate near the upper elevation of this habitat. Owners of neighboring properties could further enhance 'Alala habitat by coordinating habitat corridors to connect with one another along the north-south axis of the Kona slopes, especially in the elevational zone between 1,000 and 1,800 m. Predator control Recommendation 7: The habitat of the wild population should be managed aggressively with respect to predators, including mongooses, rats, and cats. The current practice of trapping cats, mongooses, and rats on the McCandless Ranch should be continued and expanded. Because 'Alala will frequently nest in the same locations from year to year, nest trees should be protected by electrical predator guards or aluminum flashing during the breeding season. Solar-powered electric guards have been used successfully on Guam to protect Marianas Crow nests from predation by brown tree snakes (Boiga irregularis). In addition, this year fledgling Marianas Crows were successfully protected during the vulnerable postfledging period by placing them in cages each night until they were capable of sustained flight (R. E. Beck, pers. comm., 1992). This technique should be tried with 'Alala fledglings to reduce the risk of predation. In addition to trapping, other methods, including the use of diphacinone-laced baits, should be considered when the recovery team feels that data are adequate to evaluate their safety.

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Scientific Bases for the Preservation of the Hawaiian Crow Management of the Wild Population Recommendation 8: Techniques must be developed for managing the wild population of 'Alala without risking injury to it. The goal of joint management of the captive and wild populations is to increase the size (density and distribution) of the population rapidly. The following short-term actions that can be instituted immediately are recommended: Experiment with effectiveness of food supplementation to increase nestling and fledgling survival. Determine important, safe, and practical kinds of food supplements through additional research. Promote survival of wild nestlings and fledglings with predator-control enclosures around nests aimed at mongooses, cats, and rats. Locate and promote the growth and preservation of trees that are optimal nest sites. Set up observation towers of the scaffolding type on the McCandless Ranch, e.g., four towers 1 mile apart and equipped with a high-powered, high-quality spotting scope and walkie-talkies to facilitate the documentation of habitat use, nest sites, behavior, and banding of young. Monitor and collect Kalij Pheasants and wild turkeys for disease analyses. Establish a public-education program for the 'Alala and other endangered forest species of Hawai'i. The following long-term actions that require planning, cooperation, and coordination of several parties are recommended: Improve the 'Alala's habitat through forest management and other practices that promote important fruit-bearing plants and substrates for invertebrates. Institute a long-term study of avian malaria at appropriate elevations on the Kona slopes. Investigate the possibility of vaccinating nestlings and fledglings against avian pox in order to promote increased survival. Investigate the feasibility of treating young 'Alala for malarial infections. Augment reproductive effort by using young produced in captivity for reintroduction. Design a cage-within-a-cage aviary, with a rat-proof floor, for release of the fledglings on the McCandless Ranch. Release young hatched from first clutches back into the wild immediately. Use ''soft release" methods to induce young crows to use habitat adjacent to existing 'Alala territories. They might even assimilate into newly forming groups on existing territories. Reintroduce crows in groups of two or three, not singly. Favor the McCandless Ranch region for releases until the numbers have grown substantially.

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Scientific Bases for the Preservation of the Hawaiian Crow Recommendation 9: Beginning in the 1993 breeding season, remove first clutches of eggs from the nests 5–7 days into the incubation period and carry them by hand to a hand-rearing facility on the McCandless Ranch. Allow the 'Alala pairs to incubate and rear their own second clutch without interference. Locate the holding facility near the adult population where vocalizations of wild adult birds can be heard. Observe whether adult birds respond to the hand-reared fledglings. Additional Research Recommendation 10: Additional field research is vital for the survival and recovery of the 'Alala. Increasing their numbers in the wild requires knowing what they need to live, remain healthy, reproduce, and recruit in the existing, highly modified environment. Some of the most basic biological facts are still unknown, especially regarding habitat needs, annual and seasonal food requirements, social behavior, and demographic characteristics. Most urgently needed are data on habitat requirements and the variation in food resources that are available and required through the seasons. Such data will provide specific direction for management of the property that supports the final wild population, of adjacent properties as 'Alala numbers increase, and of additional forest preserves after reintroduction or recolonization. The following pages summarize the kinds of data and observations that are most needed to help guide management of habitat as 'Alala numbers increase. The data can be gathered noninvasively, with minimal disturbance of the wild birds. Numbers Surveys of all recent 'Alala ranges should be conducted every year, including broadcasted voice recordings during the winter and very early spring (i.e., during dispersal and early territory establishment, when 'Alala are most vocal and responsive). Effort should be invested at appropriate elevations (1,000–1,800 m) on adjacent properties—i.e., Honaunau Bishop Estate Lands and Yee Hop Ranch—to determine whether additional pairs, resident solitary individuals, or occasional dispersers exist in the vicinity of the McCandless Ranch population. Surveys should also be conducted in the Ka'u District. Habitat Actual and potential resources for 'Alala need to be studied throughout their recent range, not just where they live now. Replicate study plots should be established at the McCandless Ranch and on the best areas immediately adjacent to the ranch, where 'Alala might first be able to recolonize. In addition, at least recently occupied sites remote from the McCandless Ranch should be similarly studied for comparison and to guide future management. Exclosures should be established as soon as possible for long-term studies on vegetational

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Scientific Bases for the Preservation of the Hawaiian Crow changes in the absence of impacts by grazing herbivores. Further experiments should be carries out to develop ways to re-establish native plants on ranges continuous to those occupies by livestock. Some areas should be totally enclosed using pig-control fences as have been used in Hawai'i Volcanoes National Park. Sites anticipated for future reintroductions should be of highest priority for study. Quantitative analysis should be conducted of the differences between existing 'ohi'a-koa forests inside and outside the present range of 'Alala and on the McCandless Ranch inside and outside the home ranges of the two or three remaining 'Alala groups. Special attention should be placed on measuring the composition and abundance of plant species in the forest understory; forest structure, especially age of trees and dispersion of openings within the forest; ages and patch sizes of the lava flows underlying the forest and their effects on plant species composition. Seasonal fruiting phenology and overall availability of native fleshy fruits (especially Lobeliaceae, Rubiaceae, and Freycinetia arborea) must be examined. If any resource appears to be disproportionately favored by 'Alala (e.g., some particular species of understory fruit), the limiting factors controlling dispersal and recruitment of this resource should be determined, especially the effect of grazing or rooting by cattle and pigs. Characteristics of nest sites and their vicinity should be identified, especially quantitative descriptions of the structure of vegetation, plant composition, and extent of native understory habitat within 250 m of the nest trees. Those measurements can be made after the end of the nesting season to avoid possible disturbance of any active nest. Foraging behavior The proportions of time that the 'Alala spend in foraging and roosting in different habitat types (ground, understory, vines, and canopy,) compared with the availability of these habitats within the home range of family groups, should be measured throughout the year. Special attention must be paid to the forest structure and composition where 'Alala choose to spend their time, for example, whether or not open, partially logged 'ohi'a-koa forest is used as much as closed-canopy forest patches in proportion to its occurrence on the McCandless Ranch. Food preferences of foraging 'Alala, compared with the availability of these resources, should be measured throughout the year. Of particular interest would be which fruits, if any, appear to be disproportionately favored. The behavior of 'Alala during movements away from the permanent territory, especially during fledgling-feeding and during midwinter, should be monitored to determine what they are searching for when they leave the permanent territory and how important downslope food resources are during different times of the year.

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Scientific Bases for the Preservation of the Hawaiian Crow Consideration should be given to supplementing the food supply on active territories in an effort to increase reproduction. Although initial attempts did not prove very successful (Banko and Banko, 1980; Giffin, 1983), additional experimentation is warranted. Food supplementation in a variety of species, including corvids (Yom-Tov, 1974; Hochachka and Boag, 1987; Hochachka, 1988; Dhindsa and Boag, 1990; Richner, 1992), has been shown to have a number of effects, including an advancement of laying, increased clutch size, and increased nestling survival and fledgling success. Physiology and disease The incidence and role of disease as a limiting factor among wild 'Alala are poorly known. Disease could be a dominant factor in their decline, or it could be essentially irrelevant. The issue is vital to the long-term ecology of vertebrates on the island of Hawai'i. 'Alala numbers are now too low for active study of the birds themselves in this respect. Inference through the study of other bird species is now required, and it is essential. The following are some questions that need further examination: What are the infection rates of avian malaria and avian pox among introduced and native forest birds at 1,500 m on the Kona slope, both on and off the McCandless Ranch? Does any aspect of disease incidence or vector ecology appear different on the McCandless Ranch? What are the primary and secondary breeding areas for disease vectors above 1,000 m in 'ohi'a-koa forests, especially on and near the McCandless Ranch? Are introduced birds, such as the Kalij Pheasant and wild turkey serving as disease reservoirs for malaria, pox, or other diseases? What are the nutrient components of the ancestral and introduced fruits taken by 'Alala? Do the rarer fruits (especially the ones that were common in their diet, e.g., 'ie'ie) contain elements, protein, or caloric value not replaced by those now more common? Do the introduced fruits contain elements (e.g., too much iron) that could cause long-term disorders? Social behavior We strongly discourage capturing adult birds for color-banding until their numbers increase. Initially, all data should be gathered through careful, noninvasive field observations. Like all corvids, the 'Alala clearly can tolerate nearby humans (and cattle) engaged in nonthreatening behavior. They can easily tolerate noninvasive observations made away from the nest once a complete clutch is laid; however, capture and banding activities might produce unnecessary risk and stress. Scrutiny of the few remaining wild birds will provide clues for identifying many of them without color-bands. Tape recordings should be analyzed to determine whether voice imprints can identify individual birds. Also, individual birds can possibly be tracked by documenting wing molt patterns.

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Scientific Bases for the Preservation of the Hawaiian Crow All 'Alala newly released into the wild should be banded, and these birds will begin to provide additional data on social and dispersal behavior. Some released birds should be equipped with radiotelemetry transmitters that are glued to back or rump feathers and designed to fall off with the first annual molt. These will provide data on movement patterns by nonbreeders and might also provide the best opportunity to ascertain causes of death in this age class. The role of prebreeding 'Alala in family affairs, especially in cooperative announcement or defense of territories, should be studied, as should the nature and duration of the lingering association between parents and nonbreeding offspring. The nature of dispersal forays by prebreeders should be studied, as well as the age at which they begin, how far they move, whether dispersers regularly return to the natal family group, and to what habitats and elevations dispersing nonbreeders are attracted. As to the degree of territorial aggression during the nonbreeding season, do family groups (including adjacent territorial pairs) merge, or are the nonbreeding "flocks" merely assemblages of different age classes of prebreeding 'Alala within a single family group? Demography Some of the most important demographic data are impossible to obtain from an unbanded population, especially a small population restricted to a forested habitat. Close study of the 'Alala, however, might provide clues relevant to the following unanswered questions: The causes of adult mortality. The hatchability of eggs in the first and subsequent clutches. The causes of brood reduction after hatching. The age of first breeding needs to be established for future demographic analyses. Although it is clear that some birds breed when 2 years old, the average age in males and females and the range of individual variation in age of sexual maturity need to be established. The Captive Population Findings The husbandry and management of the captive 'Alala at Olinda are inadequate, and there is room for the modification and improvement of methods and procedures. The age structure of the captive population of 10 birds is unstable and the pedigree is relatively shallow.

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Scientific Bases for the Preservation of the Hawaiian Crow The captive population needs to be expanded as rapidly as possible for demographic and genetic purposes. Incompatibility exists with some of the current pairings of the captive birds. The Captive-Breeding Facility Recommendation 11: A facility should be built that provides an optimal environment for successful breeding of the 'Alala. One husbandry facility is not adequate. The current facility is not optimal for successful breeding of the 'Alala. Characteristics of an optimal facility (or facilities) would include the following: An up-to-date library at the Olinda Facility, with continuing access to other journals and information from zoos on the mainland, including videos on various aspects of husbandry. Adequate veterinary facilities at Olinda, institutionalization of routine and emergency veterinary care, and a consistent pathology program. Additional crow enclosures that incorporate the design recommendations of experienced aviculturists from other captive-propagation programs and that allow for the safe and rapid separation of males from their mates. Increase the frequency and duration of routine daily activities around the birds to minimize the stress through conditioning. This process should be initiated during the nonbreeding season. Long-term arrangements for pathological studies with a board-certified pathologist or pathology center. The following specific features can be instituted immediately: Separate areas for juvenile and adult birds (existing structures can be used for juveniles). "Play" items in the aviaries—e.g., bark, games, or a "reward box"—to reduce aggressive behavior. More than one feeding area in each pen. A more natural environment in the form of planted aviaries, rather than wooden planters. The following specific features require planning, cooperation, and coordination of several parties: A second captive-breeding facility should be developed to provide increased security from disease or other catastrophes. This second facility should be developed in Hawai'i and its collection should be restricted to endemic Hawaiian species.

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Scientific Bases for the Preservation of the Hawaiian Crow Advice from outside experts about the design of an optimal habitat for the 'Alala. A "natural" habitat might be produced with dirt floors and vines as a natural barrier between sections of the aviary; wire, which can cause injury to the birds, should be used only when necessary. Plexiglass and larger-meshed cages to provide more light for the birds. Increased light will also allow vegetation to grow in the aviaries and enhance the health of the birds. Changes in dimensions of the pens. The pens should be lower (10–12 ft. high) and wider, so that the birds can be captured with a minimum of trauma and risk of injury. New juvenile cages that include flight areas. New breeding pens for adult breeders with a configuration more suitable for nesting, including multiple nest baskets. Breeding enclosures for individual pairs should be physically separated by about 50 meters, if possible; otherwise, visual barriers should be installed on the existing breeding pens (perhaps with tennis netting and vegetation) before the breeding season. Husbandry in the Captive-Breeding Program Recommendation 12: Husbandry at the current captive breeding program must be improved. The following actions should be instituted immediately: Re-mate birds that have been unsuccessfully paired for more than 2 years. Check semen quality of males and relate it to known history of avian pox infection. Modify breeding enclosures so that male birds can be removed from the nesting site as soon as mates lay their first eggs. Allow females to incubate eggs for 5–7 days before the eggs are removed for artificial incubation, and reintroduce males to their mates only after clutch removal. Artificially incubate eggs at a dry-bulb temperature of 100.5¹F. Monitor weight loss of each egg and adjust conditions to achieve correct loss to pip (about 12%). If necessary, radiograph eggs at the end of incubation to determine whether chicks are malpositioned within eggs. Hatch chicks under still-air conditions and use behavioral stimulation (tactile and auditory) to encourage weak chicks to hatch. Break out weak chicks as soon as possible during the pip-to-hatch interval (after the chorioallantoic blood system has shut down). Monitor nutritional state for components required for reproduction; e.g., check for normal blood concentrations of vitamin E, biotin, iron, and copper. Feed birds a more frugivorous, low-acid, low-iron diet. The following actions require training, planning, cooperation, and coordination: Develop artificial-insemination techniques using another Corvus species as an appropriate research surrogate.

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Scientific Bases for the Preservation of the Hawaiian Crow Set up more than one captive-breeding facility. Augment the captive populations until there is a minimum of 40 breeding pairs (plus the number of nonbreeders and subadults necessary to maintain this number) at two or more captive facilities. This "target" population size should be adjusted upward or downward depending on the effectiveness of other management strategies for increasing the size of the wild population. Any additions to the captive stock should be made first by taking first clutches of wild eggs and incubating them in the laboratory, second, by taking nestlings or recent fledglings, and third by taking some nonbreeding adults. Removal of adults from the wild should only be considered as a last resort. Develop chick-rearing protocols that minimize imprinting and maximize independence. Develop and implement safe and effective quarantine and sanitation procedures and protocols. Data Recommendation 13: More data on eggs, chicks, fledglings, and adults are needed to determine the causes of the lack of reproductive success of the captive population of 'Alala. General data A computerized record-keeping system that uses ISIS/ARKS and ISIS/SPARKS and an auxiliary database to track survival of eggs and chicks. ISIS/SPARKS to monitor average level of inbreeding. Systematic record-keeping, including information on breeding, fate of clutches, and egg quality. Consistent evaluation of embryo and bird mortality by qualified personnel. This will require accurate record keeping for such information as the fate of eggs and artificial incubation. Standard and regular genetic and demographic analyses on the captive population to establish annual objectives and pairing recommendations. Development of protocols for standard and nonstandard procedures, their wide circulation for peer review, and their implementation. Protocols for pathology. Specific data Vitamins, minerals, amino acids and essential chemicals that are above or below normal concentrations and that could be adversely influencing sexual behavior, reproductive physiology, fertility, hatchability of eggs, or viability of young, with emphasis on vitamin E, biotin, iron, copper, and tannins. Comparison of the reproductive condition of nonbreeding adults and active breeders, based on direct laparoscopic examination or monitoring of hormone concentrations, to determine why some adults do not breed in captivity and others do.

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Scientific Bases for the Preservation of the Hawaiian Crow Optimal conditions for artificial incubation of crow eggs. Factors to consider are temperature, humidity, turning rate, still-air versus forced-air incubation in the first 7 days of incubation, and starting incubation under the female parent to improve hatchability. The feasibility of using human-imprinted crows for artificial insemination in captive propagation. Initial experimentation should be accomplished using another Corvus species as a research surrogate. Research surrogates for this work should not be housed at Olinda or any other facility housing 'Alala. Sexual and social compatibility of all pairings. The effect of photoperiodicity on the timing of reproduction in crows. Other environmental stimuli that are necessary for reproduction, e.g., special foods for courtship feeding, perches for copulation, vocalizations, stimuli from adjacent pairs, and external stimuli that inhibit reproduction. Adults DNA analyses of all captive 'Alala to document the extent of band-sharing. Chromosome analysis of all captive 'Alala to look for chromosomal abnormalities. Electrophoretic analysis of proteins for all captive 'Alala to determine the extent of heterozygosity. Development of a complete protocol for behavioral observation, including television monitors and a blind. Information gathered would help to determine when first eggs are laid so that male birds can be removed from their breeding enclosures promptly. Measurements of what the birds are eating, as opposed to what they are fed, to determine nutritional needs, including measurement of circulating vitamins through analysis of blood samples. Weights of captive birds over time. Determination of hematological and serum norms to assist in the diagnosis of illness. Yearly veterinary evaluations, including blood sampling and screening for parasites. Observation and description of molting of birds to determine potential toxicoses and sex of the birds. Analysis of molting patterns might also help to determine the age of birds in the wild. Sex of birds according to laparoscopy performed by a qualified avian veterinarian and application of chromosomal techniques to feathers. Institution of artificial insemination techniques in the captive population of 'Alala with semen from a male nonbreeder and an imprinted female if initial breeding attempts are unsuccessful or result in the production of infertile eggs. Chicks Development of a complete protocol for behavioral observation of chicks that emphasizes the avoidance of imprinting while maximizing independence, placing of young birds with other captive crows as soon as possible, and allowing them to pick their own food as soon as possible.

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Scientific Bases for the Preservation of the Hawaiian Crow Documentation of physical and behavioral development, including growth curves, molt sequences, and food intakes. Veterinary information. Eggs Egg pathology, including bacteriological findings on all unsuccessfully hatched eggs. Bacterial culturing of dead embryos. Complete embryonic analysis. Nutrition Recommendation 14: Changes in the captive 'Alala's diet are needed. Although there are many uncertainties and unanswered questions about iron-storage disease, changes in the diet of captive 'Alala are warranted. A low-iron, low-acid balanced diet is recommended. An accurate nutritional analysis of food items in the wild is needed, and consideration should be given to simplifying the diet in captivity to ensure proper and consistent nutrition. Equipment at the Captive-Breeding Facility Recommendation 15: Equipment should be modernized to ensure the success of the captive-breeding program. The following equipment is needed to support a successful captive-breeding program: A full veterinary laboratory-clinic (equivalent to the facilities of a small-animal practice), including quarantine areas, an x-ray machine, updated video-monitoring equipment, a library, and a hatchery (with a hatching room and a brooding facility). A pathology laboratory somewhere on the Hawaiian islands. Personnel and Training Recommendation 16: A mechanism must be established for continuing training of personnel at the captive-breeding facility. Adequately trained personnel are essential to the success of the captive-breeding program. To correct current shortcomings, enhancement activities should include the following:

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Scientific Bases for the Preservation of the Hawaiian Crow A fully funded, long-term avicultural training program for staff at Olinda, including periodic visits to mainland zoos and other captive breeding facilities for workshops and additional training and programs tailored to the specific needs of trainees and the breeding facility. Training in all aspects of genetic management of small populations, including the use of computer software designed to provide those analyses. An apprenticeship program. Access to state-of-the-art technologies developed at zoos and other captive breeding facilities. The facility staff should include the following: A full-time director who serves as both a curator and an administrator. The person should be knowledgeable about both aviculture and ornithology and should be up to date on avicultural techniques. The person would be responsible for the overall management of the facilities, including training of keeper staff, time management, administration, public relations, and fund-raising. A full-time on-site avian veterinarian. A full-time on-site aviculturist. At least two additional animal-keepers. Genetics of the Wild and Captive Populations Findings The decline of the 'Alala must have been accompanied by a loss of genetic variation as a result of genetic drift and inbreeding, but the extent of this loss is unknown. Inbreeding itself is unlikely to be a major cause of the decline of the 'Alala in the wild. Lack of molecular data about historical and current levels of genetic variation in the wild population have prevented meaningful investigation of the genetic implications of the 'Alala's decline. In any case, the 'Alala population on the McCandless Ranch is so close to the wild sources of some of the captive birds that they would be expected to add no more than very slight genetic variability to the captive population, and even the current magnitude of variation will be retained only if the population is rapidly increased. Assuming that all founders of the captive population were originally unrelated (which might or might not be the case), eight of the surviving birds have calculated inbreeding coefficients of 0, and two (the female Hooku and the male Hoikei) have inbreeding coefficients of 0.25. More importantly, two of the four current breeding pairs will produce offspring with inbreeding coefficients of 0.25.

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Scientific Bases for the Preservation of the Hawaiian Crow DNA fingerprinting using two probes reveals a high proportion of band-sharing for seven captive 'Alala. A comparison of data from three other wild corvid populations suggests that the captive population is strongly inbred. The absence of comparable data from the wild 'Alala, however, limits the usefulness of these data. It is not clear whether the extant wild population is suffering from inbreeding depression caused by the loss of genetic variation. Recommendation 17: Because the wild population is so small and the need for increasing numbers of birds is so critical, addition of new wild-caught adult birds to the captive stock should have a very low priority until the wild population has increased, because this action is not likely to provide a genetic advantage. Release of captive birds on the McCandless Ranch solely for the purpose of augmenting genetic variability has no supporting rationale. Any releases must be part of a full-scale management plan. At the present time, genetic studies on the wild population should be considered to be of secondary importance. It is clear that the preservation of genetic diversity in both the captive and wild populations will require that these populations be increased in size as rapidly as possible. Until the wild and captive populations increase substantially, demographic considerations should remain the principal determinants of management activities. However, genetic analysis (e.g., DNA, electrophoresis, and chromosome analyses) should be completed on all captive birds, and on all offspring of wild pairs that are subject to manipulation in any form. This information could prove especially valuable for recovery management, but if not, we have still performed an important function of documenting data that could prove useful in future conservation efforts with other species.