Range-Wide Population Assessment of the Endangered Yellow-Naped Amazon (Amazona auropalliata)

Abstract

Yellow-naped amazons, Amazona auropalliata, have experienced a dramatic population decline due to persistent habitat loss and poaching. In 2017, BirdLife International changed the species’ status from threatened to endangered and estimated that between 10,000 and 50,000 individuals remained in the wild. An accurate estimate of the number of remaining wild individuals is critical to implementing effective conservation plans. Wright et al. conducted roost count surveys in Costa Rica and Nicaragua during 2016 and published their data in 2019; however, no population data exists for the rest of the range. We conducted roost counts at 28 sites across Mexico, Guatemala, and the Bay Islands in Roatan during 2018 and 2019. We counted 679 birds and combined our data with the published Wright et al. (2019) data for a total of 2361 wild yellow-naped amazons observed across the species’ range. There were fewer roosts detected in the northern region of the range than in the southern region. We found that roosts were most likely to occur in built-up rural and pasture habitat, with 71% found within 100 m of human habitation. Our results illustrate the need for immediate conservation action to mitigate decline, such as enforced legal action against poaching, nest guarding, and increased community education efforts.

Parrot Ownership and Capture in Coastal Ecuador: Developing a Trapping Pressure Index

“…Our interviews revealed that Lilacine Amazons were trapped both in mangroves, where they roost, and dry forests, where they feed and nest [38,39], suggesting that both adults and chicks are being taken from the wild. Anecdotal reports from communities suggest past events of outsiders casting nets over mangrove islands to remove an entire roost of Lilacines at a time.…”

Annual Censuses and Citizen Science Data Show Rapid Population Increases and Range Expansion of Invasive Rose-Ringed and Monk Parakeets in Seville, Spain

“…However, single counts at communal roosts, such as those performed here, do not allow for the identification of uncertainty in population size estimates related to detection errors, which may lead to the underestimation of real population numbers [67,68]. Despite these limitations, roost counts allow a reasonable lower bound for estimating the total population size (e.g., [66]) and its temporal changes (e.g., [68]) when individuals concentrate in well-known localities, thus reducing the probability of overlooking large flocks during census [68]. In the case of rose-ringed parakeets in Seville, we cannot discard small counting errors that may slightly affect annual population sizes, but they are overweighed by the easy locating of the largest roosts [47].…”

“…Monk parakeets, on the other hand, have grown exponentially but seem to have reached a stability of about 1500 individuals, distributed in several breeding nuclei scattered throughout the study area. Population censuses, through counts of individuals at roosts, are suitable for communal roosting species, such as some parrot species [44,[65][66][67][68]. However, single counts at communal roosts, such as those performed here, do not allow for the identification of uncertainty in population size estimates related to detection errors, which may lead to the underestimation of real population numbers [67,68].…”

“…Citizen science data have several biases that may explain these results. Although occurrence records from volunteers can be temporally and spatially biased when the detectability of the species is difficult or survey efforts are inadequate [66,[83][84][85], these biases are unlikely in this case, given that parakeets are loud and highly conspicuous [59,86], thus facilitating their detection by birdwatchers. However, volunteers can accidentally introduce sampling bias such as a misidentification between both parakeet species (which is rather unlikely due to their different morphologies and behaviors) or under-reporting, especially when these species become abundant, or simply because they are not interesting to observers [87,88].…”

Roadside Car Surveys: Methodological Constraints and Solutions for Estimating Parrot Abundances across the World

“…While roost counts may allow estimating regional and even global populations sizes of some parrot species [11,60,62,63], they are not affordable for most parrot populations and species and thus estimates of densities are often obtained using point counts or walk line transects [10]. However, these methodologies may fail to record rare and patchily distributed species, a problem that could be solved using large-scale roadside car surveys [10].…”