Seasonal roosts of Red-lored Amazons in Ecuador provide information about population size and structure

ABSTRACT.   Data from roosts of Amazona parrots may be useful in creating demographic models, because these birds exhibit high roost fidelity and pairs are conspicuous in flight. However, few investigators have attempted to track changes in the number of pairs using such roosts. We studied Red-lored Amazons ( Amazona autumnalis ) at a communal roost in southwest Ecuador over a 1-yr period to understand better their population structure. Population size was estimated at 214 individuals. Counts revealed seasonal variation in numbers, but the occurrence of pairs and singles was seldom correlated. The number of paired individuals using the roost was lower during the breeding period. In contrast, the number of single birds at the roost nearly doubled during the breeding period. Overall, our data suggest that parental responsibilities during the nesting period explain fluctuations in the number of birds at the roost, and such fluctuations can be used to estimate the reproductive portion of the population. Protection of the small mangrove islands where the parrots roost would likely benefit a population that occupies a much larger area and would, at the same time, provide a useful tool for demographic studies of this poorly known neotropical parrot.     

Postfledging Survival and Development of Juvenile Lilac-Crowned Parrots

Abstract: We fitted radiotransmitters to 68 lilac-crowned parrot (Amazona finschi) fledglings from 1996 to 2003 to determine the survival and development of juveniles during their first year after leaving the nest. Overall, first-year survival was 73% (CI = 53–94%) and all mortalities occurred within 5 weeks of fledging, with highest mortality in the first week postfledging. Survival varied between years, influencing recruitment of independent young in the population. Nesting lilac-crowned parrots produced 0.70 independent young per egg-laying pair during 1996–2003. Lowest productivity of 0.25 independent young per pair occurred in 2003, with 40% postfledging survival. Juvenile development after fledging was characterized by variations in mobility, distance from the nest, and separation distance between siblings. Mobility and distance of young birds from the nest increased linearly with months postfledging. The first 2–3 weeks after fledging were characterized by low mobility and survival of young parrots, making this the most critical phase postfledging. The dependency period for young parrots extended to 4–5 months postfledging and was characterized by increased mobility and low separation between siblings, as juveniles traveled in family groups. Independence occurred in month 5 and was marked by a significant increase in mobility and separation between siblings, indicating the break-up of family groups. The first weeks after leaving the nest were crucial for survival and highlight the need for secure habitats where fledglings can improve flight and locomotory skills. The 4–5-month dependency of young parrots may be a key period for development, enhancing survival, and establishment in the breeding population. Release programs need to replicate learning and development acquired during the postfledging dependency phase to enhance survival of captive-reared psittacines. Researchers should conduct surveys of parrot group sizes during the dependency period 1–4 months after the end of nesting to provide reliable demographic data on annual recruitment of wild populations.     

Annual pattern of fecal corticoid excretion in captive Red-tailed parrots (<Emphasis Type="Italic">Amazona brasiliensis</Emphasis>)

Annual patterns of fecal corticoid excretion were analyzed in the threatened Red-tailed parrot (Amazona brasiliensis) in captivity. Corticoid concentration over the 15 months of the study (mean ± standard error, 12.6 ± 0.32 ng g⁻¹, n = 585) was lowest around May (the southern Fall), and greatest around September (late winter), just prior to their normal breeding period. Corticoid excretion follows a seasonal pattern best explained by reproductive cycles rather than climate, although climate may be involved in the timing of corticoid excretion. Fecal corticoids also show promise as a tool to measure stress levels. We demonstrate that fecal corticoid measurement is a simple, yet efficient method for monitoring adrenocortical activity in captive, and perhaps wild, parrots. Monitoring adrenocortical activity can inform researchers about imposed stress in captivity, whether pair-bonds are forming in captive birds, and of the timing of breeding both in captivity and in nature.     

A molecular phylogeny of Amazona: implications for Neotropical parrot biogeography, taxonomy, and conservation

Amazon parrots (Genus Amazona) are among the most recognizable and imperiled of all birds. Several hypotheses regarding the evolutionary history of Amazona are investigated using a combined phylogenetic analysis of DNA sequence data from six partitions including mitochondrial (COI, 12S, and 16S) and nuclear (beta-fibint7, RP40, and TROP) regions. The results demonstrate that Amazona is not monophyletic with respect to the placement of the Yellow-faced parrot (Amazona xanthops), as first implied by. In addition, the analysis corroborates previous studies suggesting a Neotropical short-tailed parrot genus as sister to Amazona. At a finer level, the phylogeny resolves the Greater Antillean endemic species as constituting a monophyletic group, including the Central American Amazona albifrons, while further revealing a paraphyletic history for the extant Amazon species of the Lesser Antilles. The reconstructed phylogeny provides further insights into the mainland sources of the Antillean Amazona, reveals areas of taxonomic uncertainty within the genus, and presents historical information that may be included in conservation priority-setting for Amazon parrots.     

Parrot conservation and ecotourism in the Windward Islands

The genus Amazona is represented on three islands in the Windward Islands. Since Europeans first visited the region in the fifteenth century, at least three parrot species have become extinct in the Windward Islands, and today all the extant parrots of the region are endangered. Several factors have contributed to the current plight of the parrots. The authorities in each of the islands of the Windward Islands that have endemic parrots have come to the realization that sound environmental management measures can complement rather than hinder national socioeconomic goals and objectives. Consequently, regional governments have begun to explore and foster linkages between conservation and other sectors of the economy. This article examines current parrot conservation efforts in the Windward Islands and the linkages which are being fostered between tourism and other sectors of the economy. Policy and research implications of the region's current parrot conservation efforts and ecotourism programme are also considered.     

Plant food resources and the diet of a parrot community in a gallery forest of the southern Pantanal (Brazil).

Neotropical parrots usually forage in forest canopies for nectar, flowers, leaves, fruit pulp, and seeds. As they have no all-purpose territories, these birds usually exploit vegetation mosaics in order to use plentiful resources as they become available. In this study we examine the use of a gallery forest in the southern Pantanal (Brazil) by a diverse parrot community that ranged from Brotogeris chiriri (a small species) to Ara chloroptera (a large one). Plant food resources principally used by parrots were abundantly available during the rainy season (fleshy fruits), the annual floods (fleshy fruits), and the dry season (flowers). While both smaller and larger species foraged on fruits, parakeets largely consumed the pulp, while larger parrot species used pulp and seeds. In the dry season parakeets foraged extensively on nectar, especially Inga vera nectar that was abundantly available during the last two months of the dry season, the harshest period of the year. Among larger parrots, only Propyrrhura auricollis frequently harvested nectar. Fruits maturing during floods, despite being fish- or water- dispersed were extensively used by the parrots. Hence, unlike what happens in most other Neotropical dry forests, occurrence of a fruiting peak during the annual flooding, which occurs in the transition from the wet to the dry season, constitutes an extra and significant episode of food availability, since in this period, fruit production normally declines. Therefore, the unique and abundant availability of flowers and fruits in this gallery forest may account for the presence of large parrot populations in the southern Pantanal.     

Influence of environmental variability on the growth of Lilac-crowned Parrot nestlings

Growth rate parameters were analysed for Lilac-crowned Parrot Amazona finschi nestlings in the tropical dry forest of the Reserva de la Biosfera Chamela-Cuixmala, Mexico. Growth rates for psittacine species follow the inverse relation with body mass observed for neotropical landbirds, with larger parrot species exhibiting slower growth rates. There was significant variation between years in size and growth rates of Lilac-crowned Parrot nestlings with nestlings exhibiting slower growth rates in 1996 than in 1997. Food abundance for parrots also varied significantly between years, with greater food availability during the 1997 breeding season than that of 1996. The increased size and growth rates of nestlings in 1997 may have reflected this, and suggests the potential influence of environmental variability on parrot reproduction, particularly in such a markedly seasonal habitat.     

Cryptic diversity and conservation units in the Bahama parrot

Wide application of genetic approaches has enhanced the detection of cryptic diversity, even in historically well-studied organisms. In addition to improving our knowledge of biodiversity, detection of cryptic diversity can have important management implications within imperiled groups, such as the Cuban parrot complex (Amazona leucocephala). Bahama parrots (A. l. bahamensis) were once widespread throughout the archipelago, but are now restricted to the two largest islands (Abaco and Inagua). Mitochondrial DNA-based population genetic and phylogenetic analyses revealed the distinctiveness of the Abaco, Inagua and now extirpated Acklins populations, detecting diagnostic character support and reciprocal monophyly indicative of three phylogenetic species. Congruent results were obtained for the Abaco and Inagua populations based on Bayesian clustering analyses of microsatellite genotypic data. Genetic signatures of demographic contraction were identified on Abaco, but not Inagua. These findings were consistent with lower genetics-based estimates of effective population size on Abaco, as well as the disproportionate human impacts reported on the island relative to Inagua. Overall, our results suggest that the taxonomy of the Cuban parrot complex requires revision and that the conservation status of the Abaco phylogenetic species should be immediately elevated to reflect its historical isolation, recent population decline and continued threats to its persistence.     

Nesting Habitat of the Lilac-crowned Parrot in a Modified Landscape in Mexico

Parrot populations are being increasingly pressured to occupy modified or fragmented landscapes, yet little is known of the habitat requirements of most species, particularly with regard to the effects on breeding habitat. We evaluated nesting habitat of the lilac-crowned parrot Amazona finschi in the modified landscape of coastal Michoacan in Mexico. We located 90 parrot nests in 12 tree species in Michoacan, with lilac-crowned parrots presenting a narrow niche-breadth of tree species used for nesting. Considering an additional 82 nest trees recorded for lilac-crowned parrots in Jalisco, we determined a 51 percent similarity in cavity resource use by parrots in the two dry forest regions. Overall, the predominant nest tree species with 76 percent of nests were Astronium graveolens , Piranhea mexicana , Brosimum alicastrum , and Tabebuia spp., all characteristic of semi-deciduous forest. Only 8 percent of nests occurred in trees characteristic of deciduous forest. Parrots utilized large trees with canopy level cavities as nest sites, and preferred conserved semi-deciduous forest for nesting, with fewer nests than expected in deciduous forest and transformed agricultural land. Nest areas in semi-deciduous forest occurred on significantly steeper terrain, as remnant semi-deciduous forest is restricted to steep ridges and canyons. Those parrot nests in modified habitats and forest patches were located near to continuous forest, with nest trees in open agricultural land being significantly closer to continuous forest than nests in disturbed forest patches. These results demonstrate the importance of conserved semi-deciduous forest as breeding habitat for the threatened, endemic lilac-crowned parrot, making wild populations of the species vulnerable to the high rate of transformation and fragmentation of tropical dry forest.     

Seabird nest counts: a test of monitoring metrics using Red-tailed Tropicbirds

ABSTRACT.   Counts of nesting birds are often used to monitor the abundance of breeding pairs at colonies. Mean incubation counts (MICs) are counts of nests with eggs at intervals that correspond to the mean incubation period of a species. The sum of all counts during the nesting season (MIC_total) and the highest single count during the season (MIC_max) are metrics that can be generated from this method. However, the utility of these metrics as measures of the number of breeding pairs has not been well tested. We used two approaches to evaluate the bias and precision of MIC metrics for quantifying annual variation in the number of breeding Red-tailed Tropicbirds ( Phaethon rubricauda ) nesting on two islands in the Papahānaumokuākea Marine National Monument in the northwest Hawaiian Islands. First, we used data from nest plots with individually marked birds to generate simulated MIC metrics that we compared to the known number of nesting individuals. The MIC_total overestimated the number of pairs by about 5%, whereas the MIC_max underestimated the number of pairs by about 60%. However, both metrics exhibited similar precision. Second, we used a 12-yr time series of island-wide MICs to compare estimates of temporal trend and annual variation using the MIC_max and MIC_total. The 95% confidence intervals for the trend estimates were overlapping and the residual standard errors for the two metrics were similar. Our results suggest that both metrics offered similar precision for indices of breeding pairs of Red-tailed Tropicbirds, but that MIC_total was more accurate.     

Genome size variation in parrots: longevity and flying ability

Several hypotheses have been proposed to explain genome size variation in birds. However, no general consensus has been reached thus far. In this study, we analysed the inter- and intraspecific variation of genome size in some parrot species, and we tested the hypotheses that (1) weaker fliers have larger genomes, and (2) long-living species have lower DNA content. In general, parrots have a mean genome size (2.93 pg/nucleus) comparable to that of other avian orders. Amazona ochrocephala tresmariae has the highest genome size (4.30 pg/nucleus) among parrots. As expected, weaker flyers have larger genomes than better ones. In contrast to our prediction, we found a positive correlation between genome size and longevity. Finally, the species-group Amazona has a higher DNA content than the two groups Ara and Cacatua . Since oxidative stress is causally related to longevity, we suggest that DNA oxidative damage could have acted to some extent as a constraint on GS variation in parrots and perhaps also in other avian orders.     

A push‐pull integrated pest management scheme for preventing use of parrot nest boxes by invasive Africanized honey bees

Africanized honey bees (Apis mellifera scutellata) compete with endangered parrots for nest boxes and can hamper conservation efforts. We tested an integrated pest management push‐pull protocol in the Atlantic Forest in São Paulo, Brazil, in an effort to prevent bee swarms from colonizing nest boxes (N = 30 in the forest plus five in aviaries) meant for use by Vinaceous‐breasted Amazons (Amazona vinacea). Fifteen parrot nest boxes were treated with a permethrin insecticide to “push” scout bees away and each parrot box was paired with a bee trap box containing a pheromone lure to “pull” bees. Over a 1‐yr period (March 2013 to March 2014), 29 insect colonies moved into 18 of the 35 trap boxes. Nine Africanized honey bee, three native Jatai bee (Tetragonisca sp.), and 17 wasp colonies occupied trap boxes. Only one experimental push‐pull pair untreated parrot box was invaded by bees and no parrot boxes in aviaries were colonized. Four of the parrot nest boxes were occupied by birds during our study. Although none were used by Vinaceous‐breasted Amazons, Southern House Wrens (Troglodytes musculus), Green‐winged Saltators (Saltator similis), and Plain Parakeets (Brotogeris tirica) nested in the boxes and all nests were successful. Although long‐term studies are needed before drawing conclusions about the effectiveness of trap boxes, our results suggest that a push‐pull protocol may prove useful for reducing the use of nest boxes meant for parrots and other cavity‐nesting birds by Africanized honey bees and other insects.     

Low reproductive success of the endangered Takahe Porphyrio mantelli on offshore island refuges in New Zealand

Many of New Zealand's endangered birds have been transferred from the “mainland” of the North and South Islands to smaller coastal islands free from introduced predators and competitors. The transfer of Takahe Porphyrio mantelli (Plate 1) to offshore islands is unique because these highly endangered, flightless rails are being moved from alpine-tussock habitat of Fiordland, the last remaining natural population, to substantially different lowland habitat on island refuges. Despite the fact that 30% of the approximately 160 Takahe left in the wild now live on coastal islands, a detailed analysis on the success of the island populations has never been undertaken. Using data available from New Zealand's Department of Conservation, we found that while adult survivorship of Takahe on islands is high, reproductive success is significantly lower than in Fiordland. Most factors examined, including inbreeding and nutrient deficiency, had no significant effect on reproductive success of Takahe breeding on islands. Island pairs produced fewer eggs and juveniles in the first year of their pair bond relative to all other years. Hence the large number of transfers of birds between islands during the initial stages of the relocation program may have resulted in a higher frequency of pair formation and thus may have contributed to the islands' lower reproductive success. Why first clutches did so poorly (four juveniles from 43 clutches) compared with second (11 from 36) and third (six from 13) clutches is not known but was one of the main contributing factors for island pairs making greater nesting effort but significantly lower returns than birds breeding in Fiordland. In addition, some individual birds have been very successful in producing young relative to other birds, suggesting that important differences in quality of some breeders may also exist. We expect island productivity will improve over time as the number of interisland transfers of Takahe decreases and as the proportion of breeding birds raised in the island environment increases.     

Ecology of the coprophagous moth Trisyntopa neossophila Edwards (Lepidoptera: Oecophoridae)

Trisyntopa neossophila Edwards (Lepidoptera: Oecophoridae) is an unusual moth whose breeding cycle is closely synchronised with a termite mound nesting parrot of northern Australia; the hooded parrot ( Psephotus dissimilis Collet). T. neossophila is one of three coprophagous, nest dwelling moths in the genus Trisyntopa Lower 1918. True coprophagy is rare in the Lepidoptera, although some species occasionally consume faeces to gain rare nutrients. We present observations of the life cycle of T. neossophila , a moth that lays its eggs in the nest of a hooded parrot, so that larvae hatch in synchrony with the hatching of the parrot's eggs. The larvae spend their larval period in the nest and exclusively consume the excrement of the nestling parrots. When the parrot chicks fledge, the larvae move to the walls of the nest cavity to pupate, emerging the following wet season to repeat the process during the next parrot breeding season.     

Parrot behavior at a Rio Manu (Peru) clay lick: temporal patterns,associations, and antipredator responses

Although eating clay at licks (a form of geophagy) has been described, there are few behavioral data on temporal patterns, social interactions, species associations, or reactions to potential predators. We examined the behavior of nine species of macaws, parrots, and parakeets at the Machiguenga Ccolpa, a clay lick on the Rio Manu, Peru in the dry season. Three distinct mixed-species groups used the licks: in the early morning (parrots and small macaws), in mid-morning (large macaws), and in the early afternoon (parakeets), although the latter two groups used the licks at other times of day as well. The first parrots to begin eating at the lick in the early morning were yellow-crowned parrots (Amazona ochrocephala) and dusky-headed parakeets (Aratinga weddellii), followed by blue-headed parrots Pionus sordidus, and then by mealy (Amazona farinosa) and orange-cheeked (Pionopsitta barrabandi) parrots, and chestnut-fronted macaws (Ara severa). Although blue-headed parrots fed in dense groups of over 50, the others rarely exceeded 20 individuals. Scarlet macaws (A. macao) sometimes fed alone or joined the early morning groups, but most associated with a large group of red and green macaws (A. chloroptera) that arrived, often scaring off the smaller birds. On average, about 100 macaws and parrots fed in the early morning, macaw feeding groups averaging just over 40, and the parakeets averaged over 70. Average time at the lick ranged from 28 min for yellow-crowned parrots to 47 min for tui parakeets. Of the early morning group, blue-headed and mealy parrots were the most aggressive and orange-cheeked parrots were the least aggressive. Red and green macaws were more aggressive than scarlet macaws; the parakeets were equally aggressive. All species had more aggressive interactions with conspecifics than with other species. Responses to intruders and predators varied by species of parrot/macaw and type of intruder. In response to intruders or loud calls, responses could be partial (some individuals flew away, circled, and returned), temporary (all individuals flew away but returned within a few minutes), or total (all flew away and abandoned feeding for at least a half hour). The large macaws showed the lowest rate of total abandonment and the parakeets showed the highest. People passing up or down river in boats scared birds from the lick. The local residents (Machiguenga tribespeople in boats) elicited a much greater response than did the researchers. In the recent past, macaws and parrots were hunted for food, feathers, and the pet trade, and the birds response, as well as the presence of parrot and macaw feathers in local villages we visited, suggests some continued exploitation, or a long-term memory in the birds.Communicated by R.F. Oliveira     

Spatial and seasonal variation in abundance within an insular grey parrot population

Populations of Psittacidae are endangered by habitat loss and the international pet market. The grey parrot (Psittacus erithacus) is among the most traded species, yet little is known about densities and their variability in time and space. The population of grey parrots on the island of Príncipe (Gulf of Guinea) was estimated with distance sampling, in both pre‐ and postbreeding seasons. Abundance was related to a range of habitat features using generalized additive models. Densities averaged 48 ± 3 (SE) individuals km^?2 in the prebreeding and 59 ± 4 in the postbreeding season, both extremely high compared to elsewhere in Africa and to other parrot species. Despite a population of 6000–8000 individuals over only 139 km², parrots were patchily distributed, being unrecorded in ~25% of surveyed areas. Abundance varied seasonally, with densities being significantly higher in secondary compared to primary forest in the post‐ but not in the prebreeding season. Abundance was most tied to the presence of nest‐tree species prior to breeding and to feeding‐tree species and lightly sloping ground after breeding. These results highlight the need to preserve a matrix of habitat types to provide resources for parrots across seasons and ensure that surveys recognize seasonality in habitat use as a potential bias.     

Extensive consumption of Tabebuia aurea (Manso) Benth. & Hook. (Bignoniaceae) nectar by parrots in a Tecoma savanna in the southern Pantanal (Brazil).

Neotropical parrots forage for various food items such as seeds, fruit pulp, flowers, young leaves, and even arthropods. While foraging, many species wander over large areas that include both open and closed habitats. In this study, I examined parrot foraging activity during a brief synchronous and massive flowering in August 1998 in a tecoma savanna (dominated by Tabebuia aurea) in the southern Pantanal. Six parrot species, ranging from the small Brotogeris chiriri to the large Amazona aestiva, foraged for T. aurea nectar, but Nandayus nenday was by far the major nectar consumer, and the results of each of their visits, like those of the other species, was damage of a substantial proportion of the existing flower crop. Parrots foraged mostly during the afternoon, when nectar concentration tended to be higher. Nevertheless, compared to bird-pollinated flowers, which produce copious nectar, T. aurea had a smaller mean nectar volume per flower. Hence, presumably the amount of damage wreaked by these parrots resulted from their efforts to obtain part of their daily energy and water requirements. Thus, the synchronous and massive flowering occurring in such a brief period in the dry season may be related to, among other factors, the necessity of satiating predators such as parrots, which are still abundant in the Pantanal.     

Effect of nestbox type on occupancy and breeding biology of Tree Sparrows Passer montanus in central Spain

Avian life-history studies are often conducted on populations nesting in nestboxes. However, the type of nestbox used is a potentially confounding variable, as each model shows specific characteristics. In recent decades, a new commercial model of artificial nestbox made of woodcrete, a mixture of sawdust and additives, has become popular owing to its better protection against predators compared with the classic wooden design. We assess the effect of nestbox type on the breeding ecology of Tree Sparrows Passer montanus , focusing on their thermal properties, an influential factor in nestbox selection. Occupancy rates and reproductive parameters of Tree Sparrows were compared between birds breeding in woodcrete and wooden nestboxes over 5 years. Woodcrete nestboxes had a higher occupancy rate and birds breeding in them had earlier clutches, a shorter incubation period and more reproductive attempts per season than birds nesting in wooden boxes. Clutch size and nestling condition did not differ between nestbox types, but reproductive success was higher in woodcrete nestboxes. The higher temperature in woodcrete nestboxes (1.5 °C higher on average) might explain these differences. Such differences may bias results obtained in comparative studies where more than one nestbox type is used.     

The Influence of Habitat,Season, and Detectability on Abundance Estimates across an Amazonian Parrot Assemblage

The Amazon basin holds very high parrot species richness but almost nothing is known of parrot population densities in the region or how these vary between species, habitats, sites, and seasons. Such data are becoming important as humans impact on increasing areas of the region. Seventeen parrot species were surveyed using a line transect distance sampling method over 3 yr in floodplain and terra firme forests at two sites in the Tambopata region of southeast Peru. Density estimates for most species were in the range of 3.3–7.8/km², with Brotogeris cyanoptera and Amazona farinosa reaching densities of 22 and 23/km² in floodplain forest during the dry season. Parrot densities were higher in floodplain forest than in terra firme forest at both sites. The parrot communities of terra firme forests were similar across sites and seasons, but those in floodplain forests differed widely across sites and across seasons. Upper canopy birds are notoriously difficult to survey. We introduce a procedure to correct for the likely violation of the assumption that all birds on the transect line are detected (distance sampling assumption g(0) = 1). We correct g(0) based on calling rates of birds using a cue‐counting technique. Multipliers for g(0) differ across species and site, but not season. This method yielded density estimates on average 22 percent higher (6–40% higher in individual species) than those from the standard method.     

Parrot conservation in a small island-nation: Case of the Commonwealth of Dominica

The Commonwealth of Dominica, hereafter referred to as Dominica, is one of only two islands in the English-speaking Caribbean with two species of extant, endemic Amazona parrots, namely the Imperial or Sisserou Parrot (Amazona imperialistand the Red-necked or Jaco Parrot (A. arausiaca).These birds are of national as well as international significance, as their populations have been on the decline for several years. During the last 15 years the local authorities, with the support and cooperation of various regional and international agencies, have mounted a campaign to save both species from extinction. An islandwide public awareness campaign has been attempted, with encouraging results. An increase in the species population as well as an increased level of private and public support for parrot conservation, are among the positive results to date. In spite of these accomplishments, however, the parrots are not out of danger and therefore continued vigilance is necessary. Additional measures are proposed to ensure the continued existence and complete recovery of the Dominican Amazons.