DIVERSITY OF MARINE SPONGES IN THE NORTHWEST ATLANTIC by Susanna Drake Fuller Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Dalhousie University Halifax, Nova Scotia March 2011 © Copyright by Susanna Drake Fuller, 2011 DALHOUSIE UNIVERSITY DEPARTMENT OF BIOLOGY The undersigned hereby certify that they have read and recommend to the Faculty of Graduate Studies for acceptance a thesis entitled “DIVERSITY OF MARINE SPONGES IN THE NORTHWEST ATLANTIC” by Susanna Drake Fuller, in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Dated: March 4, 2011 External Examiner: _________________________________ Research Supervisor: _________________________________ Examining Committee: _________________________________ _________________________________ Departmental Representative: _________________________________ ii DALHOUSIE UNIVERSITY DATE: March 4, 2011 AUTHOR: Susanna Drake Fuller TITLE: DIVERSITY OF MARINE SPONGES IN THE NORTHWEST ATLANTIC DEPARTMENT OR SCHOOL: Department of Biology DEGREE: PhD. CONVOCATION: May YEAR: 2011 Permission is herewith granted to Dalhousie University to circulate and to have copied for non-commercial purposes, at its discretion, the above title upon the request of individuals or institutions. I understand that my thesis will be electronically available to the public. The author reserves other publication rights, and neither the thesis nor extensive extracts from it may be printed or otherwise reproduced without the author’s written permission. The author attests that permission has been obtained for the use of any copyrighted material appearing in the thesis (other than the brief excerpts requiring only proper acknowledgement in scholarly writing), and that all such use is clearly acknowledged. _______________________________ Signature of Author iii This thesis is dedicated to Ransom A. Myers, and my mother, Judith Rivinus Fuller, who would both be glad to know it is finally finished. It is also dedicated to Daniel Kehler, who inspired me to do graduate work in the first place. iv Table of Contents List of Tables ...................................................................................................................... viii List of Figures ....................................................................................................................... x Abstract .............................................................................................................................. xiii Acknowledgements ............................................................................................................ xiv Chapter 1 Introduction ........................................................................................................ 1 Chapter 2 Habitat Engineering by Sessile Marine Invertebrates: Associated Faunal Diversity and Broad Scale Patterns .................................................................................... 7 2.0 Introduction ................................................................................................................ 7 2.1 Ecosystem Engineering Activities ........................................................................... 11 2.2 Habitat Provision ...................................................................................................... 13 2.2.1 Individual Host Effects on Associated Fauna ..................................................... 14 2.2.2 Patterns Between Host Groups ............................................................................ 17 2.2.3 Skeletal Material as Habitat ................................................................................. 22 2.2.4 Topographical Complexity .................................................................................. 23 2.2.5 Sedimentation Facilitation ................................................................................... 26 2.3 Broad Scale Patterns of Associated Faunal Diversity ........................................... 28 2.3.1 Latitudinal Gradients ........................................................................................... 30 2.3.2 Depth Gradients ................................................................................................... 33 2.3.3 Host Volume ........................................................................................................ 35 2.4 Nursery Areas, Community Selection and Evolutionary Consequences ............ 36 2.5 Conclusion ................................................................................................................. 41 Chapter 3 Distribution and Ecosystem Function in Deep-water Structural Species, Based on Local Ecological Knowledge: Implications for Conservation and Management ........................................................................................................................ 55 3.0 Introduction .............................................................................................................. 55 3.1 Methods ..................................................................................................................... 59 3.2 Results ........................................................................................................................ 62 3.2.1 Selection of Interview Participants ...................................................................... 62 3.2.2 Fishing History: Gear Type, Target Species and Area Fished ............................ 62 3.2.3 Knowledge of Distribution of Corals and Sponges ............................................. 64 3.2.4 Ecological Observations of Corals and Sponges ................................................. 66 3.2.5 Fishing Impacts and Changes to the Marine Environment ................................. 66 3.3 Discussion .................................................................................................................. 68 3.3.1 Fishermen’s Contributions to Sponge and Coral Ecology .................................. 69 3.3.2 Linking Fishermen’s Knowledge and Scientific Research.................................. 71 3.3.3 Using LEK in Fisheries Management and Marine Conservation ........................ 73 3.4 Conclusion ................................................................................................................. 76 v Chapter 4 Sponge Distribution and Diversity in the Northwest Atlantic: Analysis of Fisheries Observer and Research Trawl Data ............................................. 92 4.0 Introduction .............................................................................................................. 92 4.1 Methods ..................................................................................................................... 94 4.1.1 Data Availability ................................................................................................. 94 4.1.2 Fisheries Observer Data ...................................................................................... 95 4.1.3 Identification of Sponge Samples ........................................................................ 96 4.2 Results ........................................................................................................................ 97 4.2.1 Fisheries Observer Data ...................................................................................... 97 4.2.2 Trawl Survey Data ............................................................................................... 99 4.3 Discussion ................................................................................................................ 101 4.3.1 Data Availability and Limitations ..................................................................... 101 4.3.2 Sponge Research in the Northwest Atlantic ...................................................... 102 4.3.3 Impacts of Fishing on Sponges .......................................................................... 102 Chapter 5 A Unique Monspecific Population of Vazella pourtalesi (Schmidt, 1870) (Porifera: Hexactinellida) on the Scotian Shelf, Northwest Atlantic ........................... 119 5.0 Introduction ............................................................................................................ 119 5.1 Methods ................................................................................................................... 121 5.1.1 Study Area ......................................................................................................... 121 5.1.2 Data Collection .................................................................................................. 121 5.2 Results & Discussion .............................................................................................. 124 5.2.1 Species Description ........................................................................................... 124 5.2.2 Geographical Distribution ................................................................................. 125 5.2.3 Bottom Substrate ............................................................................................... 126 5.2.4 Currents ............................................................................................................. 127 5.2.5 Community Structure and Associated Megafauna ............................................ 128 5.2.6 Life Cycle and Reproduction ............................................................................. 128 5.2.7 Threats