DOCSLIB.ORG

Forest Ecology and Management Xxx (Xxxx) Xxx

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Forest Ecology and Management Xxx (Xxxx) Xxx Forest Ecology and Management xxx (xxxx) xxx Contents lists available at ScienceDirect Forest Ecology and Management journal homepage: www.elsevier.com/locate/foreco Suitable nesting sites for specialized cavity dependent wildlife are rare in woodlands Dejan Stojanovic a,*,1, Laura Rayner b,1, Mclean Cobden a, Chris Davey 2, Stuart Harris b, Robert Heinsohn a, Giselle Owens a, Adrian D. Manning a a Fenner School, Australian National University, Canberra, Australia b ACT Parks and Conservation Service, Australian Capital Territory Government, Canberra, Australia ARTICLE INFO ABSTRACT Keywords: Non-excavating species that prefer rare combinations of cavity traits are limited to only a fraction of the available Tree hollow tree cavity resource. Understanding animal preferences and quantifying the abundance of suitable cavities is Nest hollow fundamental to protecting non-excavators. We aimed to identify the traits of trees and cavities selected by a Habitat selection vulnerable, non-excavating bird, the superb parrot Polytelis swainsonii. We also evaluated cavity abundance and Deforestation the accuracy of ground-based survey techniques (where an observer estimated the number of cavities in the Ground survey methods Carrying capacity canopy with binoculars from the ground). We then climbed trees to accurately identify true cavities and to Superb Parrot Polytelis swainsonii measure their internal dimensions. Ground-based counts of tree cavities were correlated with the true number of cavity entrances in trees. When trees had zero cavities, ground counts overestimated their abundance, but for cavity-bearing trees ground counts underestimated their abundance. We found that superb parrot nest trees contained more cavities than random trees. Superb parrots selected cavities that were deeper, with wider floors and entrance sizes than random cavities. Cavities with the combination of selected traits comprised only 0.5% of the standing cavity resource. Our results confirm that non-excavators can be very selective about the types of trees and cavities they use for nesting. Rarity of suitable cavities may be a factor limiting the population growth and recovery of superb parrots. Without accounting for the critical information gap between what is observed on the ground, and what is in fact present in trees, effective habitat management for non-excavators may be compromised by inaccurate assessments of cavity abundance and conservation status. 1. Introduction support more cavities than young ones, so older, less disturbed forests and woodlands have more cavities, higher cavity diversity, and corre­ Tree cavities are a vital habitat resource for many threatened animal spondingly diverse communities of cavity-dependent animals (Linden­ species. Animals can exhibit strong preferences for cavities with mayer et al., 2006). Unfortunately, global deforestation and cumulative particular traits, for example, entrances small enough to exclude pred­ land use change threatens persistence of mature forests and woodlands ators, or floor diameters that can accommodate a large brood (Gold­ (Hansen et al., 2013) and it severely impacts cavity-bearing trees and ingay, 2009; Cockle et al., 2011a; Stojanovic et al., 2017). For non- their dependent fauna (Lindenmayer and Sato, 2018). Managing cavity excavating species that prefer rare combinations of cavity traits, only abundance in deforested landscapes is a global conservation challenge a fraction of the available tree cavity resource is suitable (Gibbons et al., because cavity availability limits population sizes of non-excavators 2002), and this can in turn limit their populations (Ranius, 2000; Cor­ (Newton, 1994; Cornelius et al., 2008). Understanding animal prefer­ nelius et al., 2008). This is because where primary cavity excavators (e. ences and accurately quantifying the abundance of suitable cavities is g. woodpeckers) are absent, non-excavators rely on mechanical damage fundamental to protecting non-excavators (Cockle et al., 2010, 2015), and fungal decay to create cavities, but the odds of this process pro­ especially where deforestation of mature trees is ongoing (Politi et al., ducing a suitable cavity are low (Cockle et al., 2011b). Mature trees 2010). Unfortunately, this critical information is unavailable for many * Corresponding author. E-mail address: [email protected] (D. Stojanovic). 1 Indicates equal contribution. 2 Retired. https://doi.org/10.1016/j.foreco.2020.118718 Received 3 August 2020; Received in revised form 14 October 2020; Accepted 15 October 2020 0378-1127/© 2020 Elsevier B.V. All rights reserved. Please cite this article as: Dejan Stojanovic, Forest Ecology and Management, https://doi.org/10.1016/j.foreco.2020.118718 D. Stojanovic et al. Forest Ecology and Management xxx (xxxx) xxx threatened cavity-dependent animals. South Wales in winter (Higgins, 1999). Superb parrots nest in mature A major reason why this knowledge gap exists is that it can be trees and there is evidence that suitable nest cavities are reused between difficult to quantify animal preferences and the abundance of suitable breeding seasons (Manning et al., 2004). The species is social and, if cavities without directly measuring them. Climbing trees to directly enough breeding habitat is locally available, they nest in groups (Hig­ measure the dimensions of cavities can yield rich information about the gins, 1999). ecology of forests (Cockle et al., 2015). Climbing trees is not always Our study area was the northern part of the Australian Capital Ter­ undertaken due to the effort, expense and risk involved. Consequently, ritory where the species shows strong reliance on the endangered Yellow knowledge of the standing tree cavity resource is sometimes mostly Box – Blakely’s Red Gum grassy woodland ecological community. Our derived from indirect, ground-based surveys in some forests (Gibbons sites were located across three areas (details withheld) of grassy, open et al., 2002; Koch, 2008). However, ground counts can both over- and woodlands of mixed tenure, near the Canberra urban area. All sites have under-estimate the availability of tree cavities, and yield little or no ongoing grazing and browsing pressure (from native wildlife and stock), information about the most important cavity traits for wildlife – their so the canopy cover is predominantly mature trees with limited internal dimensions (Harper et al., 2004; Rayner et al., 2011; Stojanovic recruitment. et al., 2012). The gap in knowledge between what is observable from the ground and the true availability of suitable cavities is a significant 2.2. Nest identification and data collection conservation problem. For example, population viability models that use inaccurate estimates of cavity abundance may set carrying capacity too We identified superb parrot nests using behavioral cues of birds in high or low, skewing estimates of extinction risk. Given the importance potential nesting habitat (Manning et al., 2004). For every superb parrot of parameter uncertainty on population viability analysis (Brook et al., nest identified, we identified an additional randomly selected tree that 1997), reducing inherent error in carrying capacity estimates is impor­ superb parrots did not use for nesting. Random trees were selected tant. Furthermore, poor conservation outcomes are a likely result of within the same area as nest trees, but we used a DBH minimum of 50 cm ground counts if land managers decide which trees are felled or retained as a criterion for tree selection (because our field studies showed that based on flawed estimates. superb parrots do not nest in trees with DBH < 50 cm). Random trees We address the knowledge gap between ground and climbing counts comprised at least eight individuals of each of three species used as nests for a non-excavating cavity dependent bird. Superb parrots Polytelis by superb parrots in our study area: Blakely’s red gum Eucalyptus bla­ swainsonii are vulnerable (Threatened Species Scientific Committee, kelyi, inland scribbly gum E. rossii and yellow box E. melliodora. For both 2016), and one of the main threats to the species is deforestation nest and random trees, we recorded both tree- and cavity-level data. At (Manning and Lindenmayer, 2009; Manning et al., 2013) and competi­ the tree-level, we recorded: (i) superb parrot nest tree yes/no, (ii) tion for nesting cavities (Threatened Species Scientific Committee, diameter at breast height (DBH) in centimeters, (iii) health as an ordinal 2016). The superb parrot is listed as vulnerable in Australia, partly due category where 1 = perfectly healthy, 2 = early crown senescence, 3 = to concerns about scarcity of suitable nest cavities (Threatened Species moderate crown senescence, 4 = severe senescence, and 5 = dead, (iv) Scientific Committee, 2016). However, weak evidence of nest site lim­ species, (v) a ground count of the number of cavity entrances, and (vi) itation was used as to justify the species’ IUCN status of ‘least concern’ the true number of cavity entrances counted by climbing. We used a (Birdlife International, 2020). Given that cavity abundance is a critical single ground observer to eliminate observer bias in counts. The ground aspect of population limitation in birds (Newton, 1994), the availability observer was blind to the outcomes of climbing counts and tallied all of nesting sites is an important area of uncertainty that must be resolved visible cavities with a maximum estimated entrance diameter > 5 cm, to increase confidence in conservation
Load more

Recommended publications
  • §4-71-6.5 LIST of CONDITIONALLY APPROVED ANIMALS November
    §4-71-6.5 LIST OF CONDITIONALLY APPROVED ANIMALS November 28, 2006 SCIENTIFIC NAME COMMON NAME INVERTEBRATES PHYLUM Annelida CLASS Oligochaeta ORDER Plesiopora FAMILY Tubificidae Tubifex (all species in genus) worm, tubifex PHYLUM Arthropoda CLASS Crustacea ORDER Anostraca FAMILY Artemiidae Artemia (all species in genus) shrimp, brine ORDER Cladocera FAMILY Daphnidae Daphnia (all species in genus) flea, water ORDER Decapoda FAMILY Atelecyclidae Erimacrus isenbeckii crab, horsehair FAMILY Cancridae Cancer antennarius crab, California rock Cancer anthonyi crab, yellowstone Cancer borealis crab, Jonah Cancer magister crab, dungeness Cancer productus crab, rock (red) FAMILY Geryonidae Geryon affinis crab, golden FAMILY Lithodidae Paralithodes camtschatica crab, Alaskan king FAMILY Majidae Chionocetes bairdi crab, snow Chionocetes opilio crab, snow 1 CONDITIONAL ANIMAL LIST §4-71-6.5 SCIENTIFIC NAME COMMON NAME Chionocetes tanneri crab, snow FAMILY Nephropidae Homarus (all species in genus) lobster, true FAMILY Palaemonidae Macrobrachium lar shrimp, freshwater Macrobrachium rosenbergi prawn, giant long-legged FAMILY Palinuridae Jasus (all species in genus) crayfish, saltwater; lobster Panulirus argus lobster, Atlantic spiny Panulirus longipes femoristriga crayfish, saltwater Panulirus pencillatus lobster, spiny FAMILY Portunidae Callinectes sapidus crab, blue Scylla serrata crab, Samoan; serrate, swimming FAMILY Raninidae Ranina ranina crab, spanner; red frog, Hawaiian CLASS Insecta ORDER Coleoptera FAMILY Tenebrionidae Tenebrio molitor mealworm,
    [Show full text]
  • TAG Operational Structure
    PARROT TAXON ADVISORY GROUP (TAG) Regional Collection Plan 5th Edition 2020-2025 Sustainability of Parrot Populations in AZA Facilities ...................................................................... 1 Mission/Objectives/Strategies......................................................................................................... 2 TAG Operational Structure .............................................................................................................. 3 Steering Committee .................................................................................................................... 3 TAG Advisors ............................................................................................................................... 4 SSP Coordinators ......................................................................................................................... 5 Hot Topics: TAG Recommendations ................................................................................................ 8 Parrots as Ambassador Animals .................................................................................................. 9 Interactive Aviaries Housing Psittaciformes .............................................................................. 10 Private Aviculture ...................................................................................................................... 13 Communication ........................................................................................................................
    [Show full text]
  • Conservation Advice Polytelis Swainsonii Superb Parrot
    THREATENED SPECIES SCIENTIFIC COMMITTEE Established under the Environment Protection and Biodiversity Conservation Act 1999 The Minister approved this conservation advice on 5 May 2016; and confirmed this species 16 July 2000 inclusion in the Vulnerable category. Conservation Advice Polytelis swainsonii superb parrot Taxonomy Conventionally accepted as Polytelis swainsonii (Desmarest, 1826). Summary of assessment Conservation status Vulnerable: Criterion 1 A4(a)(c) The highest category for which Polytelis swainsonii is eligible to be listed is Vulnerable. Polytelis swainsonii has been found to be eligible for listing under the following listing categories: Criterion 1: A4(a)(c): Vulnerable Species can be listed as threatened under state and territory legislation. For information on the listing status of this species under relevant state or territory legislation, see http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl Reason for conservation assessment by the Threatened Species Scientific Committee The superb parrot was listed as Endangered under the predecessor to the Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act) the Endangered Species Protection Act 1992 and transferred to the EPBC Act in June 2000. This advice follows assessment of information provided by public nomination to change the listing status of Polytelis swainsonii. Public Consultation Notice of the proposed amendment and a consultation document was made available for public comment for greater than 30 business days between 17 November 2014 and 9 January 2015. Any comments received that were relevant to the survival of the species were considered by the Committee as part of the assessment process. Species Information Description The superb parrot is a medium-sized (36–42 cm long; 133–157 g weight) slender, long-tailed green parrot.
    [Show full text]
  • Breeding Ecology of the Superb Parrot, Polytelis Swainsonii In
    Technical Report Breeding ecology of the superb parrot Polytelis swainsonii in northern Canberra Laura Rayner, Dejan Stojanovic, Robert Heinsohn and Adrian Manning Fenner School of Environment and Society The Australian National University This report was prepared for Environment and Planning Directorate Australian Capital Territory Government Technical Report: Superb parrot breeding in northern Canberra Acknowledgements This technical report was prepared by Professor Adrian D. Manning and Dr Laura Rayner of the Fenner School of Environment and Society (ANU). Professor Robert Heinsohn and Dr Dejan Stojanovic of the Fenner School of Environment and Society (ANU) were integral to the design and execution of research contained within. Mr Chris Davey contributed many hours of nest searching and monitoring to this project. In addition, previous reports of superb parrot breeding in the study area, prepared by Mr Davey for the Canberra Ornithologists Group, provided critical baseline data for this work. Dr Laura Rayner and Dr Dejan Stojanovic undertook all bird banding, transmitter deployment and the majority of nest checks and tree climbing. Mr Henry Cook contributed substantially to camera maintenance and transmitter retrieval. Additional field assistance was provided by Chloe Sato, Steve Holliday, Jenny Newport and Naomi Treloar. Funding and equipment support were provided by Senior Environmental Planner Dr Michael Mulvaney of the Environment and Planning Directorate (Environment Division) and Ecologist Dr Richard Milner of the Territory and Municipal Services Directorate (ACT Parks and Conservation Service). Spatial data of superb parrot breeding trees and flight paths for the Canberra region were provided by the ACT Conservation Planning and Research Directorate, (ACT Government). Mr Daniel Hill and Mr Peter Marshall of Canberra Contractors facilitated access to a nest tree located within the Throsby Development Area.
    [Show full text]
  • PRINCESS PARROT Polytelis Alexandrae
    Threatened Species of the Northern Territory PRINCESS PARROT Polytelis alexandrae Conservation status Australia: Vulnerable Northern Territory: Vulnerable Princess parrot. ( Kay Kes Description Conservation reserves where reported: The princess parrot is a very distinctive bird The princess parrot is not resident in any which is slim in build, beautifully plumaged conservation reserve in the Northern and has a very long, tapering tail. It is a Territory but it has been observed regularly in medium-sized parrot with total length of 40- and adjacent to Uluru Kata Tjuta National 45 cm and body mass of 90-120 g. The basic Park, and there is at least one record from colour is dull olive-green; paler on the West MacDonnell National Park. underparts. It has a red bill, blue-grey crown, pink chin, throat and foreneck, prominent yellow-green shoulder patches, bluish rump and back, and blue-green uppertail. Distribution This species has a patchy and irregular distribution in arid Australia. In the Northern Territory, it occurs in the southern section of the Tanami Desert south to Angas Downs and Yulara and east to Alice Springs. The exact distribution within this range is not well understood and it is unclear whether the species is resident in the Northern Territory. Few locations exist in the Northern Territory where the species is regularly seen, and even Known locations of the princess parrot. then there may be long intervals (up to 20 years) between records. Most records from = pre 1970; • = post 1970. the MacDonnell Ranges bioregion are during dry periods. For more information visit www.denr.nt.gov.au Ecology • extreme fluctuations in number of mature individuals.
    [Show full text]
  • Volume 2. Animals
    AC20 Doc. 8.5 Annex (English only/Seulement en anglais/Únicamente en inglés) REVIEW OF SIGNIFICANT TRADE ANALYSIS OF TRADE TRENDS WITH NOTES ON THE CONSERVATION STATUS OF SELECTED SPECIES Volume 2. Animals Prepared for the CITES Animals Committee, CITES Secretariat by the United Nations Environment Programme World Conservation Monitoring Centre JANUARY 2004 AC20 Doc. 8.5 – p. 3 Prepared and produced by: UNEP World Conservation Monitoring Centre, Cambridge, UK UNEP WORLD CONSERVATION MONITORING CENTRE (UNEP-WCMC) www.unep-wcmc.org The UNEP World Conservation Monitoring Centre is the biodiversity assessment and policy implementation arm of the United Nations Environment Programme, the world’s foremost intergovernmental environmental organisation. UNEP-WCMC aims to help decision-makers recognise the value of biodiversity to people everywhere, and to apply this knowledge to all that they do. The Centre’s challenge is to transform complex data into policy-relevant information, to build tools and systems for analysis and integration, and to support the needs of nations and the international community as they engage in joint programmes of action. UNEP-WCMC provides objective, scientifically rigorous products and services that include ecosystem assessments, support for implementation of environmental agreements, regional and global biodiversity information, research on threats and impacts, and development of future scenarios for the living world. Prepared for: The CITES Secretariat, Geneva A contribution to UNEP - The United Nations Environment Programme Printed by: UNEP World Conservation Monitoring Centre 219 Huntingdon Road, Cambridge CB3 0DL, UK © Copyright: UNEP World Conservation Monitoring Centre/CITES Secretariat The contents of this report do not necessarily reflect the views or policies of UNEP or contributory organisations.
    [Show full text]
  • Species Threatenedsuperb Parrot Polytelis Swainsonii
    Australian Species ThreatenedSuperb Parrot Polytelis swainsonii CONSERVATION STATUS COMMONWEALTH: Vulnerable (Environment Protection and Biodiversity Conservation Act 1999) AUSTRALIAN CAPITAL TERRITORY: Vulnerable (Nature Conservation Act 1980) NEW SOUTH WALES: Vulnerable (Threatened Species Conservation Act 1995) VICTORIA: Threatened (and listed under the Flora and Fauna Guarantee Act 1988) The Superb Parrot is a striking bird found in central woodland areas of southern WHERE DOES IT LIVE? New South Wales (NSW), the Australian The parrots are found in the NSW Capital Territory (ACT) and Victoria. southwest slopes as well as northern Already under threat from land clearing, parts of the ACT and north central loss of hollows, and lack of regeneration Victoria. Each spring they retreat towards of woodland habitat, this species may the southwest to breed, mainly in River soon be faced with another challenge and Blakely’s red gums. They then – the common myna bird. move further north and east, relying on Photo: Katherine Miller woodland habitat for flowers, fruits and seed, particularly in box and Blakely’s red gum. As one of the many Australian WHAT DOES IT bird species that uses tree hollows for breeding, clearing of woodland areas DID YOU KNOW... LOOK LIKE? has had a large impact on the parrot and, • The total population of the Superb The Superb Parrot is a medium-sized with minimal replacement of old trees, Parrot is estimated to be only a few bird with a long slender tail. Both males its numbers may continue to decline in thousand birds and females have a green body, although the future. • It is the official emblem of NSW’s the plumage on males tends to be more Boorowa Shire brilliant.
    [Show full text]
  • Superb Parrot Conservation Research Plan
    Superb Parrot Conservation Research Plan Version 2: 29 July 2020 PLAN DATE PREPARED FOR CWP Renewables Pty Ltd Bango Wind Farm Contact 1: Leanne Cross P. (02) 4013 4640 M. 0416 932 549 E. [email protected] Contact 2: Alana Gordijn P. (02) 6100 2122 M. 0414 934 538 E. [email protected] PREPARED BY Dr Laura Rayner P. (02) 6207 7614 M. 0418 414 487 E. [email protected] on behalf of The National Superb Parrot Recovery Team BACKGROUND The Superb Parrot ................................................................................................................................................................2 PURPOSE Commonwealth compliance .......................................................................................................................................................2 PROJECT OVERVIEW Primary aims of proposed research ...................................................................................................................3 SCOPE OF WORK Objectives and approach of proposed research ...................................................................................................3 PROJECT A Understanding local and regional movements of Superb Parrots ....................................................................................................... 3 PROJECT B Understanding the breeding ecology and conservation status of Superb Parrots .......................................................................... 3 SIGNIFICANCE Alignment of project aims with recovery plan objectives
    [Show full text]
  • Superb Parrot Conservation Research Plan
    Superb Parrot Conservation Research Plan PLAN DATE 17 August 2020 PREPARED FOR Coppabella Wind Farm Pty Ltd Coppabella (Yass Valley) Wind Farm Contact: Medard Boutry P. (02) 9008 1728 E. [email protected] PREPARED BY Dr Laura Rayner P. (02) 6207 7614 M. 0466 391 722 E. [email protected] on behalf of The National Superb Parrot Recovery Team BACKGROUND ........................................................................................................................................................................................................................................... 2 PURPOSE ...................................................................................................................................................................................................................................................... 2 PROJECT OVERVIEW ................................................................................................................................................................................................................................ 3 SCOPE OF WORK ...................................................................................................................................................................................................................................... 3 SIGNIFICANCE ...........................................................................................................................................................................................................................................
    [Show full text]
  • Running Head: POULTRY, PARROTS, and PEOPLE
    Running head: POULTRY, PARROTS, AND PEOPLE Poultry, Parrots, and People: Exploring Psyche Through the Lens of Avian Captivity A dissertation submitted by Elizabeth MacLeod Burton-Crow to Pacifica Graduate Institute in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Depth Psychology with emphases in Community Psychology, Liberation Psychology, and Ecopsychology This dissertation has been accepted for the faculty of Pacifica Graduate Institute by: Dr. G. A. Bradshaw, Chair Dr. Craig Chalquist, Reader Dr. Jo-Ann Shelton, External Reader ProQuest Number:13425083 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. ProQuest 13425083 Published by ProQuest LLC ( 2018). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, MI 48106 - 1346 POULTRY, PARROTS, AND PEOPLE iii Abstract Poultry, Parrots, and People: Exploring Psyche Through the Lens of Avian Captivity by Elizabeth MacLeod Burton-Crow What was the last interaction you had with a bird? Was it a cordial conversation with a parrot or indirectly, as while devouring deviled eggs? The colorful ways in which avian and human lives are connected are as nuanced as they are pervasive. Perhaps this is unsurprising, given that globally, birds are held in captivity by the billions.
    [Show full text]
  • Breeding Ecology of the Superb Parrot Polytelis Swainsonii in Northern Canberra
    Technical Report Breeding ecology of the superb parrot Polytelis swainsonii in northern Canberra Nest Monitoring Report 2016 Laura Rayner, Dejan Stojanovic, Robert Heinsohn and Adrian Manning Fenner School of Environment and Society Australian National University This report was prepared for Environment, Planning and Sustainable Development Directorate Australian Capital Territory Government Technical Report II: Superb parrot breeding in northern Canberra 2016 Acknowledgements This technical report was prepared by Professor Adrian D. Manning and Dr Laura Rayner of the Fenner School of Environment and Society, The Australian National University (ANU). Professor Robert Heinsohn and Dr Dejan Stojanovic of the Fenner School of Environment and Society (ANU) contributed to conceptualisation of research within. Chris Davey contributed many hours of nest searching and monitoring to this project. In addition, previous reports of superb parrot breeding in the study area, prepared by Davey for the Canberra Ornithologists Group, provided critical baseline data for this work. Henry Cook contributed to nest checks and camera maintenance. Field assistance was provided by Dr Chloe Sato and Lachlan Bailey. Funding and administrative support was provided by Dr Michael Mulvaney, Dr Richard Milner, Dr Margaret Kitchin and Clare McInnes of the Environment, Planning and Sustainable Development Directorate, ACT Government. Disclaimers The views and opinions expressed in this paper are those of the authors and do not necessarily reflect the views of the Australian Capital Territory Government. Knowledge and understanding of many aspects of the superb parrot's ecology and biology may be imperfect, uncertain or non-existent. The Superb Parrot is listed as Vulnerable in the ACT, and at Commonwealth and international levels.
    [Show full text]
  • Of Parrots 3 Other Major Groups of Parrots 16
    ONE What are the Parrots and Where Did They Come From? The Evolutionary History of the Parrots CONTENTS The Marvelous Diversity of Parrots 3 Other Major Groups of Parrots 16 Reconstructing Evolutionary History 5 Box 1. Ancient DNA Reveals the Evolutionary Relationships of the Fossils, Bones, and Genes 5 Carolina Parakeet 19 The Evolution of Parrots 8 How and When the Parrots Diversified 25 Parrots’ Ancestors and Closest Some Parrot Enigmas 29 Relatives 8 What Is a Budgerigar? 29 The Most Primitive Parrot 13 How Have Different Body Shapes Evolved in The Most Basal Clade of Parrots 15 the Parrots? 32 THE MARVELOUS DIVERSITY OF PARROTS The parrots are one of the most marvelously diverse groups of birds in the world. They daz- zle the beholder with every color in the rainbow (figure 3). They range in size from tiny pygmy parrots weighing just over 10 grams to giant macaws weighing over a kilogram. They consume a wide variety of foods, including fruit, seeds, nectar, insects, and in a few cases, flesh. They produce large repertoires of sounds, ranging from grating squawks to cheery whistles to, more rarely, long melodious songs. They inhabit a broad array of habitats, from lowland tropical rainforest to high-altitude tundra to desert scrubland to urban jungle. They range over every continent but Antarctica, and inhabit some of the most far-flung islands on the planet. They include some of the most endangered species on Earth and some of the most rapidly expanding and aggressive invaders of human-altered landscapes. Increasingly, research into the lives of wild parrots is revealing that they exhibit a corresponding variety of mating systems, communication signals, social organizations, mental capacities, and life spans.
    [Show full text]