{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T16:46:19Z","timestamp":1776962779769,"version":"3.51.4"},"reference-count":68,"publisher":"Cambridge University Press (CUP)","issue":"6","license":[{"start":{"date-parts":[[2021,4,8]],"date-time":"2021-04-08T00:00:00Z","timestamp":1617840000000},"content-version":"unspecified","delay-in-days":158,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["cambridge.org"],"crossmark-restriction":true},"short-container-title":["J. Trop. Ecol."],"published-print":{"date-parts":[[2020,11]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>While populations of the Endangered Grey Parrot <jats:italic>Psittacus erithacus<\/jats:italic> have collapsed across its range, the species remains remarkably abundant on the island of Pr\u00edncipe, Gulf of Guinea. We examine how aspects of its ecology interplay with local environmental conditions, to inform conservation strategies for this species and other large parrots. On Pr\u00edncipe, parrots breed in large trees of common species, with nest densities (42 \u00b1 34 km<jats:sup>\u22122<\/jats:sup>) greatly exceeding those for any comparably sized parrot. Productivity is high (1.9 chicks per cavity), probably reflecting the absence of nest competitors and predators. Food sources are abundant and much of the island is inaccessible to trappers, so many nests are successful each year. Historically harvest has involved taking only chicks from trees in a few traditional patches. These conditions have combined to allow Grey Parrots to thrive on Pr\u00edncipe, while elsewhere nest trees are timber targets, nest competition and nest predation are likely to be more intense, trapping is indiscriminate, and few areas remain unexploited by trappers. Preservation of large trees as breeding refugia, and vigilance against the indiscriminate trapping of adult birds, are identified as key conditions to stabilize and recover mainland Grey Parrot populations and indeed large parrots generally, given their very similar ecological traits and anthropogenic circumstances.<\/jats:p>","DOI":"10.1017\/s0266467421000031","type":"journal-article","created":{"date-parts":[[2021,4,8]],"date-time":"2021-04-08T09:09:26Z","timestamp":1617872966000},"page":"293-297","update-policy":"https:\/\/doi.org\/10.1017\/policypage","source":"Crossref","is-referenced-by-count":5,"title":["What can the abundance of Grey Parrots on Pr\u00edncipe Island tell us about large parrot conservation?"],"prefix":"10.1017","volume":"36","author":[{"given":"Simon","family":"Valle","sequence":"first","affiliation":[]},{"given":"Nigel J.","family":"Collar","sequence":"additional","affiliation":[]},{"given":"Martim","family":"Melo","sequence":"additional","affiliation":[]},{"given":"Stuart J.","family":"Marsden","sequence":"additional","affiliation":[]}],"member":"56","published-online":{"date-parts":[[2021,4,8]]},"reference":[{"key":"S0266467421000031_ref15","unstructured":"CITES (2017) Notification to the parties No. 2017\/010 \u2013 Reservations on Appendices I and II."},{"key":"S0266467421000031_ref17","unstructured":"D\u00e4ndliker, G (1992) The Grey Parrot in Ghana: a population survey, a contribution to the biology of the species, a study of its commercial exploitation and management recommendations. 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