Invasive Toads Shift Predatorprey Densities in Animal Communities By

Total Page:16

File Type:pdf, Size:1020Kb

Invasive Toads Shift Predatorprey Densities in Animal Communities By Ecology, 96(9), 2015, pp. 2544–2554 Ó 2015 by the Ecological Society of America Invasive toads shift predator–prey densities in animal communities by removing top predators 1,2,6,7 2 3 4 5 J. SEAN DOODY, REBEKAH SOANES, CHRISTINA M. CASTELLANO, DAVID RHIND, BRIAN GREEN, 4 6 COLIN R. MCHENRY, AND SIMON CLULOW 1Department of Ecology and Evolutionary Biology, 569 Dabney Hall, University of Tennessee, Knoxville, Tennessee 37996-1610 USA 2Department of Biological Sciences, Monash University, Clayton, Victoria 3800 Australia 3Utah’s Hogle Zoo, 2600 Sunnyside Avenue, Salt Lake City, Utah 84108 USA 4Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria 3800 Australia 5Institute for Applied Ecology, University of Canberra, Australian Capital Territory 2601 Australia 6School of Environmental and Life Sciences, University of Newcastle, Callaghan, New South Wales 2308 Australia Abstract. Although invasive species can have substantial impacts on animal communities, cases of invasive species facilitating native species by removing their predators have rarely been demonstrated across vertebrate trophic linkages. The predictable spread of the invasive cane toad (Rhinella marina), however, offered a unique opportunity to quantify cascading effects. In northern Australia, three species of predatory monitor lizards suffered severe population declines due to toad-induced lethal toxic ingestion (yellow-spotted monitor [Varanus panoptes], Mertens’ water monitor [V. mertensi], Mitchell’s water monitor [V. mitchelli]). We, thus, predicted subsequent increases in the abundance and recruitment of prey species due to the reduction of those predators. Toad-induced population-level declines in the water monitor species approached 50% over a five-year period spanning the toad invasion, apparently causing fledging success of the Crimson Finch (Neochmia phaeton) to increase from 55% to 81%. The consensus of our original and published long-term data is that invasive cane toads are causing predators to lose a foothold on top-down regulation of their prey, triggering shifts in the relative densities of predator and prey in the Australian tropical savannah ecosystem. Key words: cane toad; common tree snake; Crimson Finch; Crocodylus johnstoni; Gilbert’s dragon lizard; monitor lizard; Neochmia phaeton; Rhinella marina; top predator; trophic cascade; Varanus spp. INTRODUCTION nities and ecosystems (Terborgh and Estes 2010, Trophic downgrading, or the disappearance of top Thomsen et al. 2010). As such, there is an urgent need consumers, including apex predators, may be one of the for research to forecast the effects of trophic downgrad- most pervasive anthropogenic influences on nature, and ing on future ecosystems (Estes et al. 2011). has been linked to a plethora of processes worldwide, Invasive species are a major threat to native species including biodiversity loss, the spread of invasive via individual direct effects such as predation, compe- species, wildfire frequency, disease transmission, and tition, and poisoning (reviewed in Simberloff and alterations in water, atmosphere, and soil (Estes et al. Rejmanek [2011]). If these individual effects are partic- 2011). The loss of top predators can influence biodiver- ularly strong, they may translate into population-level sity by shifting the relative abundance of species across impacts, or even extirpations and extinctions (Blackburn trophic levels (Eisenberg 2010). Theory predicts that the et al. 2004, Doody et al. 2009). If the affected species are largest impacts of the loss of predators will be on the predators, we would predict further shifts in communi- next trophic level down, manifest as ‘‘facilitation,’’ or ties and ecosystems via facilitation. Indeed, a major type the increase in density or biomass of one species through of facilitation is predatory release, or outbreaks, in its interaction with another (Thomsen et al. 2010). species caused by declines in top predators (Soule´et al. Facilitation is a recent addition to ecological theory, 1988). Although there are numerous examples of despite its ubiquity and importance for ecological and predatory release, there are few demonstrated cases of evolutionary processes (Bruno et al. 2003, Kikvidze and releases triggered by an invasive species across trophic Callaway 2009). At the biodiversity level, facilitation is levels of vertebrates (reviews in Rodriguez [2006], White now thought to play a major role in shaping commu- et al. [2006], Letnic et al. [2009]). Yet, invasive species that are dispersing in a predictable manner offer a unique opportunity to test predictions involving trophic Manuscript received 8 July 2014; revised 5 November 2014; cascades and trophic downgrading. accepted 18 November 2014; final version received 4 March 2015. Corresponding editor: J. B. Yavitt The (terrestrial) large mammal fauna of Australia is 7 E-mail: [email protected] depauperate relative to other continents, leaving mon- 2544 September 2015 TOADS SHIFT PREDATOR–PREY DENSITIES 2545 itor lizards to occupy a role of top or near-top predators level declines in previous studies (Letnic et al. 2008, (Johnson et al. 2007, Sutherland et al. 2010). However, Doody et al. 2009, 2014). Prey species of these predators Australian monitor lizards are evolutionarily naı¨ve to counted during these surveys were the Gilbert’s dragon the cane toad (Rhinella marina), a toxic invasive species (Lophognathus gilberti) and the common tree snake that poisons many predators that attempt to ingest it (Dendrelaphis punctulata). Five surveys were conducted (reviewed in Shine [2010]). The steady westward march annually during May–June 2009–2013 along the Ord of cane toads across tropical Australia offers an ideal River, Western Australia (15848030.0100 S, 128844015.1200 opportunity to use before-and-after studies to determine E to 128859006.2900 S, 128842014.7400 E; Fig. 1). Surveys the ecological impact of toads on native species, and were conducted under sunny conditions, and each research has revealed severe population-level declines in survey involved counts along 46 km of river during monitor lizards coincident with toad invasion (Griffiths 08:30–15:30 hours (Fig. 1). Surveys involved visual and McKay 2007, Doody et al. 2009, 2014, Ujvari and searching for target species on the shoreline, on trees Madsen 2009). Moreover, emerging from this research and logs, vegetation (terrestrial, emergent, and floating), was evidence for increases in the monitors’ prey and man-made structures (piers and docks). The boat following their demise (Doody et al. 2006, 2009, 2013, was kept between 7–10 m from the shoreline during Brown et al. 2011). surveys. There were three observers, including the Here, we address the prediction that cane toads are driver, and one scribe, who did not observe. Air and shifting the relative densities of predator and prey in water temperature were taken five times during each animal communities in the riparian ecosystem of survey at 08:30, 10:15, 12:30, 14:15, and 15:30 hours. tropical Australia, via direct impacts on monitor lizards and indirect impacts on their prey. We quantified the Crimson Finch fledging success relative abundance of predators and their prey for five To determine if toads facilitated Crimson Finches years spanning the arrival of the invasive cane toad, (Neochmia phaeton) by boosting fledging success, we including four species of predators (the monitor lizards used a snapshot nest appearance method to estimate Varanus mertensi, V. mitchelli, and V. panoptes, and the fledging success across 2011–2013 along 13 km of the freshwater crocodile Crocodylus johnstoni), and three Ord River (Fig. 1). We collected nests late in the nesting prey species of those predators (the Crimson Finch period (2011, N ¼ 42 nests; 2012, N ¼ 35 nests; 2013, N ¼ Neochmia phaeton, the Gilbert’s dragon lizard Lopho- 48 nests) and scored each nest as preyed upon or fledged, gnathus gilberti, and the common tree snake Dendrela- based on nest appearance and condition, presence of phis punctulata). We review published data for other feces or egg shells, and signs of damage, such as holes, species to update the overall ecological impact of cane tearing, or distorted entrances. toads on the vertebrate food web. To inform managers, We validated the snapshot method in 2011 by we predict future impacts of cane toads on animal comparing the estimate for each nest to its known fate; communities as they invade the last remaining toad-free the known fate was determined in an intensive study of area of tropical Australia. reproductive success of a larger sample of nests in 2011 that included the 42 nests in the above estimate (Soanes MATERIALS AND METHODS 2011). During the intensive study, visual searches for Toad surveys active finch nests among shoreline vegetation were To determine the timing of toad arrival, we conducted conducted by boat along the same 13 km of the Ord five annual 13 km long surveys of the M1 Channel Road, River used in the snapshot method (Fig. 1). When which runs parallel to the M1 Channel and stems from possible, adult birds were opportunistically followed for the Ord River, near Kununurra, Western Australia several minutes to attempt to discover their nest site, but (15841022.4100 S, 128844031.0800 Eto158470306200 S, the majority of nests were located directly, due to their 128843004.0500 E; Fig. 1, see Plate 1). Surveys were conspicuousness (in emergent Pandanus trees just above conducted by two observers and one driver on rainless water). Once located, the stage of each nest was nights at 19:30–21:00 h in late May and early June, 2009– determined (building, laying, incubation, or chick 2013, from a car travelling at 15 km/h. Surveys involved rearing) and its contents, such as the number of eggs visual searches for toads with the aid of spotlights. or chicks and chick developmental stage, were assessed. Notes on parent and chick behavior during monitoring Predator and prey surveys were also recorded. All active nests were checked by To determine direct effects of toads on the relative boat, on average, every three days until fledging or nest abundance of native predators, we used visual encounter failure occurred.
Recommended publications
  • Demonstration of Facilitation Between Microalgae to Face Environmental Stress Emna Krichen, Alain Rapaport, Emilie Le Floc’H, Eric Fouilland
    Demonstration of facilitation between microalgae to face environmental stress Emna Krichen, Alain Rapaport, Emilie Le Floc’H, Eric Fouilland To cite this version: Emna Krichen, Alain Rapaport, Emilie Le Floc’H, Eric Fouilland. Demonstration of facilitation between microalgae to face environmental stress. Scientific Reports, Nature Publishing Group, 2019, 9 (16076), pp.1-12. 10.1038/s41598-019-52450-9. hal-02315867 HAL Id: hal-02315867 https://hal.archives-ouvertes.fr/hal-02315867 Submitted on 14 Oct 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Demonstration of facilitation between microalgae to face environmental stress Emna Krichen1,2, Alain Rapaport2, Emilie Le Floc’h1, and Eric Fouilland1,* 1UMR MARBEC, Univ. Montpellier, CNRS, IFREMER, IRD, Sete,` France 2UMR MISTEA, Univ. Montpellier, INRA, SupAgro, Montpellier, France *[email protected] ABSTRACT Positive interactions such as facilitation play an important role during the biological colonization and species succession in harsh or changing environments. However, the direct evidence of such ecological interaction in microbial communities remains rare. Using common freshwater microalgae isolated from a High Rate Algal Pond HRAP treating wastewaters, we investigated with both experimental and modeling approaches the direct facilitation between two algal strains during the colonization phase.
    [Show full text]
  • 2007 Birds in a Changing Climate
    T HE S TATE OF A USTRALIA ’ S B IRDS 2 0 0 7 Birds in a Changing Climate Compiled by Penny Olsen Supplement to Wingspan, vol. 14, no. 4, December 2007 2 The State of Australia’s Birds 2007 The State of Australia’s Birds 2007 3 The term climate change is commonly used to refer to shifts in modern climate, including the rise in average surface temperature known as global warming or the enhanced greenhouse effect. We use it here to refer to anthropogenic climate change, under the presumption that it is overwhelmingly caused by humans and hence has potential to largely be stabilised or reversed. The State of Australia’s Birds report series presents an overview of the status of the nation’s birds, the major threats they face and the conservation actions needed. This fifth annual report focuses on climate change. The climate is always changing and birds respond by adapting and evolving. However, at least since the very early 1900s the surface temperature of the earth has been warming at a rate unprecedented in human history, bringing with it shifts in local, regional and global weather systems. The vast majority of scientists agree that this is almost all attributable to the release of excessive amounts of greenhouse gases through human activity, particularly the use of fossil fuels and deforestation. Australia has warmed by 0.9 ° C since 1900, most rapidly since 1950, and is expected to warm a further 1 ° C over the next two decades. Signs of this change are already reflected in the distribution and abundance of some of our birds and in the timing of their breeding and migration, in line with changes observed in other biota.
    [Show full text]
  • The Crimson Finch
    PUBLISHED FOR BIRD LOVERS BY BIRD LOVERS life Aviarywww.aviarylife.com.au Issue 04/2015 $12.45 Incl. GST Australia The Red Strawberry Finch Crimson Finch Black-capped Lory One Week in Brazil The Red-breasted Goose ISSN 1832-3405 White-browed Woodswallow The Crimson Finch A Striking Little Aussie! Text by Glenn Johnson Photos by Julian Robinson www.flickr.com/photos/ozjulian/ Barbara Harris www.flickr.com/photos/12539790@N00/ Jon Irvine www.flickr.com/photos/33820263@N07/ and Aviarylife. Introduction he Crimson Finch Neochmia phaeton has Talways been one of the rarer Australian finches in captivity, and even more so since the white- the mid-late 1980’s, when the previously legal bellied. The trapping of wild finches in Australia was crown is dark prohibited across all states. They unfortunately brown, the back and have a bad reputation for being aggressive, wings are paler brown washed with red, the tail and this together with the fact that they is long, scarlet on top and black underneath. are reasonably expensive in comparison to The cheeks along with the entire under parts are many other finches, could well be a couple deep crimson, the flanks are spotted white, and of the main reasons as to why they are not so the centre of the belly is black in the nominate commonly kept. race and white for N. p. evangelinae, and the Description beak is red. Hens are duller, with black beaks. They are an elegant bird, generally standing There are two types of Crimson Finches, the very upright on the perch, and range from 120- black-bellied, which is the nominate form and 140mm in length.
    [Show full text]
  • An Update of Wallacels Zoogeographic Regions of the World
    REPORTS To examine the temporal profile of ChC produc- specification of a distinct, and probably the last, 3. G. A. Ascoli et al., Nat. Rev. Neurosci. 9, 557 (2008). tion and their correlation to laminar deployment, cohort in this lineage—the ChCs. 4. J. Szentágothai, M. A. Arbib, Neurosci. Res. Program Bull. 12, 305 (1974). we injected a single pulse of BrdU into pregnant A recent study demonstrated that progeni- CreER 5. P. Somogyi, Brain Res. 136, 345 (1977). Nkx2.1 ;Ai9 females at successive days be- tors below the ventral wall of the lateral ventricle 6. L. Sussel, O. Marin, S. Kimura, J. L. Rubenstein, tween E15 and P1 to label mitotic progenitors, (i.e., VGZ) of human infants give rise to a medial Development 126, 3359 (1999). each paired with a pulse of tamoxifen at E17 to migratory stream destined to the ventral mPFC 7. S. J. Butt et al., Neuron 59, 722 (2008). + 18 8. H. Taniguchi et al., Neuron 71, 995 (2011). label NKX2.1 cells (Fig. 3A). We first quanti- ( ). Despite species differences in the develop- 9. L. Madisen et al., Nat. Neurosci. 13, 133 (2010). fied the fraction of L2 ChCs (identified by mor- mental timing of corticogenesis, this study and 10. J. Szabadics et al., Science 311, 233 (2006). + phology) in mPFC that were also BrdU+. Although our findings raise the possibility that the NKX2.1 11. A. Woodruff, Q. Xu, S. A. Anderson, R. Yuste, Front. there was ChC production by E15, consistent progenitors in VGZ and their extended neurogenesis Neural Circuits 3, 15 (2009).
    [Show full text]
  • A Review of the Distribution, Status and Ecology of the Star Finch Neochmia Ruficauda in Queensland
    AUSTRALIAN 278 BIRD WATCHER AUSTRALIAN BIRD WATCHER 1998, 17, 278-289 A Review of the Distribution, Status and Ecology of the Star Finch Neochmia ruficauda in Queensland by GLENN H.OLMES, P.O. Box 1246, Atherton, Queensland 4883 Summary The Star Finch Neochmia ruficauda has been recorded in 35-37 one-degree blocks in Queensland. Most records concern the Edward River, Princess Charlotte Bay and Rockharnpton districts. Viable populations are probably now restricted to Cape York Peninsula. Typical habitat comprises grasslands or grassy open woodlands, near permanent water or subject to regular inundation. Some sites support shrubby regrowth caused by the clearing of formerly unsuitable denser woodlands. Recorded food items are all seeds, of five grass species and one sedge. Precise nest records are few, but large numbers of juveniles have been observed during the last two decades at Aurukun, Pormpuraaw, Kowanyarna and Princess Charlotte Bay. Threatening processes are discussed; livestock grazing in riparian situations is considered the most deleterious. Introduction The distribution, status and ecology of the Star Finch Neochmia ruficauda in Queensland require urgent review. Endemic to northern and eastern Australia, its populations have declined in most regions. Available evidence suggests that the greatest contraction in its distribution has occurred in Queensland (e.g. Blakers et al. 1984). It is extinct in New South Wales, but its distribution there was only oflirnited extent (Holmes 1996). The Star Finch is protected stringently in Queensland because it is gazetted as Endangered under the Nature Conservation Act 1992. This categorisation takes due account of 'biological vulnerability, extent of current knowledge ... and management needs'.
    [Show full text]
  • NESTLING MOUTH Marklngs It '" "' of OLD WORLD FINCHES ESTLLU MIMICRY and COEVOLUTION of NESTING
    NESTLING MOUTH MARklNGS It '" "' OF OLD WORLD FINCHES ESTLLU MIMICRY AND COEVOLUTION OF NESTING r - .. ;.-; 5.i A&+.FINCHES .-. '4 AND THEIR VIDUA BROOD PARASITES - . , , . :.. - i ' -, ,' $*.$$>&.--: 7 -.: ',"L dt$=%>df;$..;,4;x.;b,?b;.:, ;.:. -, ! ,I Vt .., . k., . .,.-. , .is: 8, :. BY ERT B. PAYNE MISCELLANEOUS PUBLICATIONS MUSEUM OF ZOOLOGY, UNIVERSITY OF MICHIGAN, NO. 194 Ann ntwi day, 2005 lSSN 0076-8405 PUBLICATIONS OF THE MUSEUM OF ZOOLOGY, UNIVERSITY OF MICHIGAN NO. 194 J. B. BLJR(.H,Editor JI.:NNIFERFBLMLEE, Assistcint Editor The publications of the Museum of Zoology, The University of Michigan, consist primarily of two series-the Mi.scel/aneous Pziblications and the Occa.siona1 Papers. Both series were founded by Dr. Bryant Walker, Mr. Bradshaw H. Swales, and Dr. W.W. Newcomb. Occasionally thc Museum publishes contributions outside of these series; beginning in 1990 thcsc arc titled Special Publications and arc numbered. All submitted manuscripts to any of the Museum's publications receive external review. The Occasional Papers, begun in 1913, serve as a medium for original studies based principally upon the collections in the Museum. They arc issued separately. When a sufficient number of pages has been printed to make a volume, a title page, table of contents, and an index are supplied to libraries and individuals on the mailing list for the series. The Miscellaneotls Pt~hlication.~,initiated in 1916, include monographic studies, papers on field and museum techniques, and other contributions not within the scope of the Occasional Papers, and are published separately. It is not intended that they be grouped into volurnes. Each number has a title page and, when necessary, a table of contents.
    [Show full text]
  • Grassfinch Decline and Local Extinction of the Crimson Finch Neochmia Phaeton in the Fitzroy River Basin, Queensland
    Australian Field Ornithology 2016, 33, 133–142 http://dx.doi.org/10.20938/afo33133142 Grassfinch decline and local extinction of the Crimson Finch Neochmia phaeton in the Fitzroy River Basin, Queensland Wayne A. Houston* and Robert L. Black Central Queensland University, School of Medical and Applied Sciences, Bruce Highway, Rockhampton QLD 4702, Australia *Corresponding author. Email: [email protected] Abstract. Many granivorous birds of northern Australia, including several species of grassfinches (Estrildidae), have PROOF suffered substantial range contractions in the last 50–100 years, apparently as a result of changes in cattle grazing and fire-management regimes. The Crimson FinchNeochmia phaeton was once widespread in woodlands and savannas of north-eastern Australia, including the extensive Fitzroy River Basin, where it was recorded in all the major subcatchments until the middle of last century. However, surveys in 2006–2008 show that it is now confined to a relatively small area in the north-east of the Basin. A tall river grass, Chionachne Chionachne cyathopoda, is an important component—for food and cover—of its habitat. Complex braiding of river channels, as at the confluence of rivers, is typical of the area where the Finches have persisted, possibly because it increases the availability of water and food, and reduces pressure from cattle grazing during the wet season. A recent local loss of the species was noted in one area where landholders used riparian fencing to maintain greater grazing intensity throughout the year, leading to suppression of Chionachne seeding. Thus, although generally favourable for conservation management, riparian fencing can also be used detrimentally.
    [Show full text]
  • The Key Role of Agroforestry and Soil Health in the Ecological Intensification of Agriculture
    The key role of Agroforestry and Soil Health in the Ecological Intensification of Agriculture Edmundo Barrios Eco-Intensive Agriculture Conference – KNAW Amsterdam, The Netherlands - 21 April 2015 Outline 1) Degrading our natural capital 2) Agroforestry: ecological facilitation in action 3) Linking trees, soil biota and ecosystem services 4) Fostering knowledge sharing 5) Challenges and opportunities Outline 1) Degrading our natural capital Millennium Ecosystem Assessment 2001-2005 Steffen et al. 2004 IGBP Planetary Boundaries Rockstrom et al. 2009 Ecology & Society Planetary Boundaries Steffen et al. 2015 Science BIODIVERSITY IN PERSPECTIVE Planned and managed AGBD aboveground biodiversity Above-ground: planned, managed biodiversity ? ? BGBD Unplanned and unmanaged Below-ground:belowground unplanned, unmanagedbiodiversity biodiversity ? Diversitas 2005 DEFORESTATION AND BIODIVERSITY LOSS BRAZILIAN AMAZON (1988-2008) 3.5 3.0 2.5 2.0 1.5 1.0 Million year per deforested Million ha 0.5 0 Nepstad, 2008 WWF-UNFCC BGBD likely higher than Aboveground 7000* 51.4* *updated using Bardgett & van der Putten 2014 Nature Barrios 2007 Ecological Economics Are we looking at the tip of the iceberg? Aboveground biodiversity Belowground biodiversity SOIL BIOLOGICAL FUNCTION AND THE PROVISION OF ECOSYSTEM SERVICES Adapted from Kibblewhite et al 2008 in Barrios et al, 2012 SOIL HEALTH A measure of the state of natural capital that reflects the capacity of soil to respond to agricultural management by maintaining both the agricultural production and the provision
    [Show full text]
  • A Preliminary Assessment of Faunal Values Within and Adjacent EPC 1029, Styx Basin, Central-East Queensland
    A preliminary assessment of faunal values within and adjacent EPC 1029, Styx Basin, central-east Queensland ) Prepared for Yeats Consulting Engineers by Ed Meyer, Ecological Consultant,S Luscombe Street, Runcorn QLD 4113 ([email protected]) Conditions of use This report may only be used for the purposes for which it was commissioned. The use of this report, or part thereof, for any other reason or purpose is prohibited without the written consent of the author. Front cover: Fauna recorded from EPC 1029 during March 2011 surveys. Clockwise from upper left: ornamental snake (Denisonia maculata); squatter pigeon (southern race) (Geophaps scripta scripta); metallic snake-eyed skink (Cryptoblepharus metal/icus); and eastern sedgefrog (Litoria tal/ax). ©Edward Meyer 2011 5 Luscombe Street, Runcorn QLD 4113 E-mail:[email protected] Version 2 _ 3 August 2011 2 Table of contents 1. Summary 4 2. Background 6 Description of study area 6 Nomenclature 6 Abbreviations and acronyms 7 3. Methodology 9 General approach 9 ) Desktop assessment 9 Likelihood of occurrence assessments 10 Field surveys 11 Survey conditions 15 Survey limitations 15 4. Results 17 Desktop assessment findings 17 Likelihood of occurrence assessments 17 Field survey results -fauna 20 Field survey results - fauna habitat 22 Habitat for conservation significant species 28 ) 5. Summary and conclusions 37 6. References 38 Appendix A: Fauna previously recorded from Desktop Assessment Study Area 41 Appendix B: likelihood of occurrence assessments for conservation significant fauna 57 Appendix C: March 2011 survey results 73 Appendix D: Habitat photos 85 Appendix E: Habitat assessment proforma 100 3 1. Summary The faunal values of land within and adjacent Exploration Permit for Coal (EPe) 1029 were investigated by way of desktop review of existing information as well as field surveys carried out in late March 201l.
    [Show full text]
  • Ecology and Evolution of Facilitation Among Symbionts
    REVIEW ARTICLE DOI: 10.1038/s41467-018-06779-w OPEN Ecology and evolution of facilitation among symbionts Flore Zélé 1, Sara Magalhães 1, Sonia Kéfi 2 & Alison B. Duncan 2 Facilitation occurs when one species positively impacts the fitness of another, and has predominantly been studied in free-living species like plants. Facilitation can also occur among symbiont (mutualistic or parasitic) species or strains, but equivalent studies are 1234567890():,; scarce. To advance an integrated view of the effect of facilitation on symbiont ecology and evolution, we review empirical evidence and their underlying mechanisms, explore the factors favouring its emergence, and discuss its consequences for virulence and transmission. We argue that the facilitation concept can improve understanding of the evolutionary forces shaping symbiont communities and their effects on hosts. 1 cE3c: Centre for Ecology, Evolution, and Environmental Changes, Faculty of Sciences, University of Lisbon, Edifício C2, piso-3, 1749-016 Lisboa, Portugal. 2 ISEM, Université de Montpellier, CNRS, EPHE, IRD, Montpellier Cedex 05, France. Correspondence and requests for materials should be addressed to A.B.D. (email: [email protected]) NATURE COMMUNICATIONS | (2018)9:4869 | DOI: 10.1038/s41467-018-06779-w | www.nature.com/naturecommunications 1 REVIEW ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/s41467-018-06779-w t is now widely accepted that interacting species can positively First, we outline the different mechanisms of impact one another1–5. Facilitation (Box 1) is one of the symbiont–symbiont facilitation. Next, we investigate the ecolo- Ibroadest terms referring to these positive interactions (Fig. 1). gical and evolutionary conditions favouring the occurrence and Its history is anchored in that of plant–plant interactions, maintenance of facilitation between symbiotic organisms.
    [Show full text]
  • Indicus Biological Consultants
    Indicus Biological Consultants Darwin City Waterfront (Darwin Wharf) Redevelopment Terrestrial fauna assessment December 2003 James Smith Ronald Firth This document is and shall remain the property of Indicus Biological Consultants. The document may only be used for the purposes for which it was commissioned and in accordance with the Terms of the Engagement for the commission. Unauthorised use of this document in any form whatsoever is prohibited. 29 Aralia Street, Nightcliff phone: (08) 8411 0350 email: [email protected] Contents www.indicusbc.netfirms.com Terrestrial Fauna Assessment Darwin City Waterfront Redevelopment December 2003 CONTENTS INTRODUCTION .....................................................................................................................................................................3 SURVEY METHODS ................................................................................................................................................................3 Bird counts ........................................................................................................................................................................3 Active Searches .................................................................................................................................................................3 Incidental records ..............................................................................................................................................................4 Bat
    [Show full text]
  • 5Th Australasian Ornithological Conference 2009 Armidale, NSW
    5th Australasian Ornithological Conference 2009 Armidale, NSW Birds and People Symposium Plenary Talk The Value of Volunteers: the experience of the British Trust for Ornithology Jeremy J. D. Greenwood, Centre for Research into Ecological and Environmental Modelling, The Observatory, Buchanan Gardens, University of St Andrews, Fife KY16 9LZ, Scotland, [email protected] The BTO is an independent voluntary body that conducts research in field ornithology, using a partnership between amateurs and professionals, the former making up the overwhelming majority of its c13,500 members. The Trust undertakes the majority of the bird census work in Britain and it runs the national banding and the nest records schemes. The resultant data are used in a program of monitoring Britain's birds and for demographic analyses. It runs special programs on the birds of wetlands and of gardens and has undertaken a series of distribution atlases and many projects on particular topics. While independent of conservation bodies, both voluntary and statutory, much of its work involves the provision of scientific evidence and advice on priority issues in bird conservation. Particular recent foci have been climate change, farmland birds (most of which have declined) and woodland birds (many declining); work on species that winter in Africa (many also declining) is now under way. In my talk I shall describe not only the science undertaken by the Trust but also how the fruitful collaboration of amateurs and professionals works, based on their complementary roles in a true partnership, with the members being the "owners" of the Trust and the staff being responsible for managing the work.
    [Show full text]