Conservation and Ecology of the Endangered Fire Salamander (Salamandra Infraimmaculata) Ori Segev a THESIS SUBMITTED for THE
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Conservation and ecology of the endangered fire salamander ( Salamandra infraimmaculata ) Ori Segev A THESIS SUBMITTED FOR THE DEGREE "DOCTOR OF PHILOSOPHY" University of Haifa Faculty of Science and Science Education Department of Evolution and Environmental Biology NOVEMBER, 2009 Conservation and ecology of the endangered fire salamander ( Salamandra infraimmaculata ) By: Ori Segev Supervised by: Leon Blaustein A THESIS SUBMITTED FOR THE DEGREE "DOCTOR OF PHILOSOPHY" University of Haifa Faculty of Science and Science Education Department of Evolution and Environmental Biology NOVEMBER, 2009 Recommended by: ________________ Date: _____________ (Advisor) Approved by: ____________________ Date: _____________ (Chairman of Ph.D. Committee) i Acknowledgments ii Table of contents Abstract ………………………………………………………………….…..................…vii List of Tables ………...………………..……………………………………………........…x List of Figures ………………………………...…….……………………..….……….….xii General Introduction ……………..…………………………….……...............................1 Amphibian decline …………………………………………………………………..1 Salamandra distribution and conservation status ………………………………......2 Population size and breeding phenology ………………...……………...........…….3 Invasive species ……………………..…………………………………...………….4 Breeding strategies and habitat selection ………………………………...........…...5 Priority effects ………………………………………………………...……….……6 Chapter 1. Population size, structure and phenology of an endangered salamander at temporary and permanent breeding sites .........................8-29 Abstract...............................................................................................................9 Introduction.......................................................................................................10 Methods.............................................................................................................13 Results...............................................................................................................16 Population size ...........................................................................................15 Residence timing and duration, phenology, and synchronization with rain ...........................................................................16 Discussion................................. .......................................................................17 Conservation management implications ....................................................19 Figures 1-4.................................................................................................22 Tables 1-4...................................................................................................26 iii Chapter 2. Deleterious effects by mosquitofish ( Gambusia affinis ) on the endangered fire salamander ( Salamandra infraimmaculata )……......30-54 Abstract............................................................................................................31 Introduction......................................................................................................32 Materials and Methods.....................................................................................34 Natural pool observations .........................................................................34 Mesocosm experiment ...............................................................................36 Results..............................................................................................................39 Natural pool survey ...................................................................................39 Mesocosm experiment ...............................................................................40 Discussion........................................................................................................42 Figures 1-5................................................................................................47 Tables 1-3..................................................................................................52 Chapter 3. Spatio-temporal progeny allocation strategies in the fire salamander: a model and empirical test ........................................................................55-82 Abstract............................................................................................................56 Introduction......................................................................................................57 The model.........................................................................................................59 The environment ........................................................................................60 Larval load and survival ...........................................................................61 Increment in Reproductive Success ...........................................................61 Accumulated reproductive success ............................................................63 Accumulated reproductive success of fixed clutch strategy ......................64 iv Model predictions ......................................................................................65 Larviposition Experiment...................................................................................66 Statistical analysis .....................................................................................67 Experimental results ..................................................................................67 Discussion..........................................................................................................68 Figures 1-8................................................................................................72 Tables 1-3..................................................................................................80 Chapter 4. Priority effects of the early breeding fire salamander on the late breeding banded newt ( Triturus vittatus )..............................................83-101 Abstract............................................................................................................84 Introduction......................................................................................................85 Methods............................................................................................................87 Urodele survey at Secher pool ..................................................................87 Artificial pool experiment .........................................................................88 Statistical analysis ....................................................................................90 Results..............................................................................................................91 Field survey ...............................................................................................91 Artificial pool experiment 1......................................................................91 Effects on invertebrates ............................................................................91 Effects on Triturus during Salamandra period .........................................92 Overall effects on Triturus ........................................................................92 Artificial pool experiment 2......................................................................93 Combined results of experiments 1 and 2.................................................93 Discussion........................................................................................................93 v Figures 1-4................................................................................................96 Tables 1-2................................................................................................100 General Discussion ..........................................................................................................102 References ………………………………………….......……………...............……......110 vi Conservation and ecology of the endangered fire salamander (Salamandra infraimmaculata ) By: Ori Segev Abstract Amphibian faunas have been declining globally for the last three decades, including in protected, supposedly pristine as well as unprotected areas. This process, which is seems to be non-random and for many species unidirectional, is apparently driven by multiple factors acting independently or in synergism driving amphibian populations’ decline, range constriction and extinction. Although the fire salamander, Salamandra infraimmaculata has been classified globally and locally endangered, critical information on its phenology, interspecific interactions and habitat selection are lacking to critically assess its true status and to properly develop conservation and management plans. Salamandra breeding sites and surrounding terrestrial habitats are threatened by various factors including contamination, desiccation, introduced species, and habitat destruction, alteration and fragmentation. As a keystone amphibian species, the absence of larval Salamandra can also potentially impact the entire ecological community. In this thesis, I addressed and found the following: (1) Although S. infraimmaculata is considered an endangered species, little is known about its population size and structure. Mark-recapture estimates of population size in several breeding sites in northern Israel revealed populations larger than previously assumed and a strong effect of breeding site permanence - populations at sites having