Seafloor Geomorphology as Benthic Habitat

The conservation of marine benthic biodiversity is a recognised goal of a number of national and international programs such as the United Nations Convention on Biodiversity (CBD). In order to attain this goal, information is needed about the distribution of life in the ocean so that spatial conservation measures such as marine protected areas (MPAs) can be designed to maximise protection within boundaries of acceptable dimensions. Ideally, a map would be produced that showed the distribution of benthic biodiversity to enable the efficient design of MPAs. The dilemma is that such maps do not exist for most areas and it is not possible at present to predict the spatial distribution of all marine life using the sparse biological information currently available.

Knowledge of the geomorphology and biogeography of the seafloor has improved markedly over the past 10 years. Using multibeam sonar, the benthic ecology of submarine features such as fjords, sand banks, coral reefs, seamounts, canyons, mud volcanoes and spreading ridges has been revealed in unprecedented detail.

This book provides a synthesis of seabed geomorphology and benthic habitats based on the most recent, up-to-date information. Introductory chapters explain the drivers that underpin the need for benthic habitat maps, including threats to ocean health, the habitat mapping approach based on principles of biogeography and benthic ecology and seabed (geomorphic) classification schemes. Case studies from around the world are then presented. They represent a range of seabed features where detailed bathymetric maps have been combined with seabed video and sampling to yield an integrated picture of the benthic communities that are associated with different types of benthic habitat. The final chapter examines critical knowledge gaps and future directions for benthic habitat mapping research.

• Reviews and compares the different methodologies currently being used
• Includes global case studies
• Provides geological expertise into what has traditionally been a biological discipline

Conservation planners and managers, conservation scientists, geologists, environmental managers, ecologists, and marine resource managers

Foreword

Preface

Contributors

1. Why Map Benthic Habitats?

2. Habitat Mapping and Marine Management

3. Anthropogenic Threats to Benthic Habitats

4. Biogeography, Benthic Ecology, and Habitat Classification Schemes

5. Surrogacy

6. Seafloor Geomorphology—Coast, Shelf, and Abyss

7. Phanerogam Meadows

8. Predictive Modeling of Dominant Macroalgae Abundance on Temperate Island Shelves (Azores, Northeast Atlantic)

9. Methane-Related Carbonate Cementation of Marine Sediments and Related Macroalgal Coralligenous Assemblages in the Northern Adriatic Sea

10. Coastal Kelp Forest Habitat in the Baie des Chaleurs, Gulf of St. Lawrence, Canada

11. The Wadden Sea in the Netherlands

12. Sand Wave Field

13. Benthic Habitat Variations over Tidal Ridges, North Sea, the Netherlands

14. Fine-Scale Geomorphological Mapping of Sandbank Environments for the Prediction of Macrobenthic Occurrences, Belgian Part of the North Sea

15. Large Submarine Sand Waves and Gravel Lag Substrates on Georges Bank Off Atlantic Canada

16. The Yongala’s “Halo of Holes”—Systematic Bioturbation Close to a Shipwreck

17. Submarine De Geer Moraines in the Kvarken Archipelago, the Baltic Sea

18. Habitats and Benthos of an Evolving Fjord, Glacier Bay, Alaska

19. Geomorphic Features and Benthic Habitats of a Sub-Arctic Fjord

20. Seabed Character and Habitats of a Rocky Antarctic Coastline

21. Fringing Reefs of the Seychelles Inner Granitic Islands, Western Indian Ocean

22. Coral Reefs and Reef Islands of the Amirantes Archipelago, Western Indian Ocean

23. Hyperspectral Remote Sensing of the Geomorphic Features and Habitats of the Al Wajh Bank Reef System, Saudi Arabia, Red Sea

24. Mesophotic Coral Reefs of the Puerto Rico Shelf

25. Geomorphic Features and Infauna Diversity of a Subtropical Mid-Ocean Carbonate Shelf

26. Geomorphology of Reef Fish Spawning Aggregations in Belize and the Cayman Islands (Caribbean)

27. Submerged Reefs and Aeolian Dunes as Inherited Habitats, Point Cloates, Carnarvon Shelf, Western Australia

28. Seafloor Morphology and Coral Habitat Variability in a Volcanic Environment

29. Habitats and Benthos at Hydrographers Passage, Great Barrier Reef, Australia

30. Two Shelf-Edge Marine Protected Areas in the Eastern Gulf of Mexico

31. Nontropical Carbonate Shelf Sedimentation. The Archipelago Pontino (Central Italy) Case History

32. Habitats of the Cap de Creus Continental Shelf and Cap de Creus Canyon, Northwestern Mediterranean

33. Rock Ridges in the Central English Channel

34. Characterization of Shallow Inshore Coastal Reefs on the Tasman Peninsula, Southeastern Tasmania, Australia

35. Rocky Reef and Sedimentary Habitats Within the Continental Shelf of the Southeastern Bay of Biscay

36. Rock Reefs of British Columbia, Canada

37. Seabed Habitats of the Southern Irish Sea

38. Habitats and Demersal Fish Communities in the Vicinity of Albatross Bank, Gulf of Alaska

39. Seabed Habitat of a Glaciated Shelf, German Bank, Atlantic Canada

40. Identifying Potential Habitats from Multibeam Echosounder Imagery to Estimate Abundance of Groundfish

41. Open Shelf Valley System, Northern Palaeovalley, English Channel, UK

42. Benthos Supported by the Tunnel-Valleys of the Southern North Sea

43. Benthic Habitats and Benthic Communities in Southeastern Baltic Sea, Russian Sector

44. Inland Tidal Sea of the Northeastern Pacific

45. Cold-Water Coral Distribution in an Erosional Environment

46. Habitat Mapping of a Cold-Water Coral Mound on Pen Duick Escarpment (Gulf of Cadiz)

47. Habitats at the Rockall Bank Slope Failure Features, Northeast Atlantic Ocean

48. Evaluating Geomorphic Features as Surrogates for Benthic Biodiversity on Australia’s Western Continental Margin

49. Habitats of the Chella Bank, Eastern Alboran Sea (Western Mediterranean)

50. Habitat Heterogeneity in the Nazaré Deep-Sea Canyon Offshore Portugal

51. Banks, Troughs, and Canyons on the Continental Margin off Lofoten, Vesterålen, and Troms, Norway

52. Distribution of Hydrocorals Along the George V Slope, East Antarctica

53. The Cook Strait Canyon, New Zealand

54. The Ascension–Monterey Canyon System

55. A Study of Geomorphological Features of the Seabed and the Relationship to Deep-Sea Communities on the Western Slope of Hatton Bank (NE Atlantic Ocean)

56. Seafloor Habitats and Benthos of a Continental Ridge

57. Habitats and Benthos of a Deep-Sea Marginal Plateau, Lord Howe Rise, Australia

58. Seamounts, Ridges, and Reef Habitats of American Samoa

59. Mapping Condor Seamount Seafloor Environment and Associated Biological Assemblages (Azores, NE Atlantic)

60. Cold-Water Coral Colonization of Alboran Sea Knolls, Western Mediterranean Sea

61. Fluid Venting Through the Seabed in the Gulf of Cadiz (SE Atlantic Ocean, Western Iberian Peninsula)

62. Habitats of the Su Su Knolls Hydrothermal Site, Eastern Manus Basin, Papua New Guinea

63. Southern Kermadec Arc–Havre Trough Geohabitats and Biological Communities

64. GeoHab Atlas of Seafloor Geomorphic Features and Benthic Habitats

Appendix 1. Questionnaire Completed by All Case Study Authors

Glossary