Project ABIS

Project ABIS

Project A.B.I.S. Annapolis Biodiversity Index Study The five year observational study initiated by the Artificial Reef Society of BC (ARSBC), and conducted by citizen scientist divers in order to document and catalogue the gradual recruitment of marine life on artificial reef Annapolis. Prepared by: Doug Pemberton Director of Biological Monitoring ARSBC Taxons compiled by Donna Gibbs Research Diver/Taxonomist, Ocean Wise MAY 2021 INDEX 1 – INTRODUCTION………………………………………………………………………………1 Artificial reefs………………………………………………………………………………1 Howe Sound………………………………………………………………………………..1 2 - BACKGROUND………………………………………………………………………………..3 Artificial Reef Society of BC………………………………………………………………3 Process of reefing…………………………………………………………………………3-4 History of Halkett Bay……………………………………………………………………..4 Site selection and survey requirements…………………………………………………….4 3 – A.B.I.S. PROJECT……………………………………………………………………………..4 Aims and objectives……………………………………………………………………….4 Diving the Annapolis………………………………………………………………………5 Labelled photos of Annapolis……………………………………………………………..5-6 4 – CONCLUSIONS……………………………………………………………………………….6 Observations of marine life growth………………………………………………………..6 Production vs. Attraction debate…………………………………………………………..7 Graph of marine life accumulation 2015-2021……………………………………………7 Halkett Bay east comparison link…………………………………………………………8 5 – TAXON………………………………………………………………………………………..9 List of 177 species to date………………………………………………………………..9-17 6 – A.B.I.S. Pictures………………………………………………………………………………18-28 7 – APPENDIX 1…………………………………………………………………………………30-33 8 – ACKNOWLEDGEMENTS…………………………………………………………………...34 References…………………………………………………………………………………34 1 - INTRODUCTION It is a fact that nearly ninety-five percent of all marine life is found in only five percent of the oceans, that thin sliver bordering the coastlines of landmasses down to a depth of about 300 feet. Unfortunately, over the past several decades this crucial and sensitive environment around the world has come under serious stresses that have, in many areas, resulted in detrimental changes to the marine environment including habitat destruction and the depletion of once common fish stocks. One positive step that has shown encouraging results towards rejuvenating a marine environment is the creation of stable and sustaining habitats in the form of human-made reefs that are able to support marine life in otherwise barren, unproductive or impacted areas where there is a lack of adequate and needed stable marine substrate to support an abundance of sea life. Areas such as solid, prominent reefs that rise above a flat, featureless bottom support a far greater amount and variety of marine life than their flat surroundings. Artificial reefs, when correctly employed, constitute an important tool to enhance environmental complexity (Bohnsack 1991). In recent times, the repurposing of properly prepared ships, planes, and other structures has been used successfully to mitigate the effects of environmental abuse and neglect. Several studies have identified that reef size significantly influences the biomass and the total numbers of species and individuals (Campos and Gamboa, 1989; Bohnsack et al 1994; Bombace et al 1994) with the efficiency of artificial reefs as attractors being far greater when formed into structures rather than disaggregated pieces (Moffitt et al, 1989). The size of an artificial reef can vary from a few metres2 (Ocean Wise rockfish project, Porteau Cove 2019) to tens of thousands of metres2. The idea of artificial reefs is not new. They have been used by civilizations around the world for hundreds of years. They have been used as both marine life aggregators in impacted areas as well as fishing inhibitors by being used as anti-trawling devices (Relini et al, 1999 and Wong, 1991). However the idea to deploy completely decontaminated, obsolete ships as marine habitats, research platforms, educational opportunities and recreational destinations is relatively new to human history. The convoluted coastline of British Columbia stretches over 25,000 kilometres and marine life variety and concentrations can vary greatly due to a combination of natural factors such as surrounding geography, tidal exchanges and current flow patterns, exposure to open ocean, fresh water input from rivers streams and seasonal runoff. Anthropogenic factors such as population density and commercial and industrial development also contribute a major impact. You cannot, for example compare the quantity and diversity of marine life around Vancouver with that of the remote northern coast of BC or the west coast of Vancouver Island. Just north of Vancouver, a scenic coastal fjord, Átl’ka7tsem/Howe Sound cuts 43 kms north into the Coast mountain range. Átl’ka7tsem/Howe Sound is situated within the unceded territory of the Skwxwú7mesh Úxwumixw/Squamish Nation and with its steeply sloped mountains, rugged coastline and scattered islands it is a visually stunning area and has become a favoured destination for recreational activities as well as residential development, with over 70,000 people presently residing in communities along the shores of Átl’ka7tsem/Howe Sound or on islands within the sound. The geography of Átl’ka7tsem/Howe Sound plays a large part in its ecology. One of the main natural influences on the sound is the Squamish River which flows down from the coastal range of mountains and discharges a large amount of fresh 1 water at the north end of Átl’ka7tsem/Howe Sound. Dozens of creeks and drainages also carry a great deal of seasonal snowmelt runoff from the surrounding mountains into the sound. These factors significantly decrease salinity and increase sediment levels within the sound. Due to its close proximity to Vancouver and easy access by road, rail and water, Átl’ka7tsem/Howe Sound has also seen a great deal of commercial and industrial activity over the past century. Logging and log boom storage, two pulp mills, a copper mine, a chemical plant and commercial fishing, have all had an influence on the environmental health of Átl’ka7tsem/Howe Sound and left their detrimental legacy of pollution, habitat degradation and fish stock depletion. Much of the heavy industry has ceased in recent decades but much damage was done. In the case of some fish species, such as Landsat 8 satellite view of Howe Sound lingcod and rockfish, their numbers have been reduced by over 90% and some species of rockfish such as black rockfish Sebastes melanops1and Bocaccio rockfish Sebastes paucispinis have been virtually eliminated from the sound. The problems faced by marine life in Átl’ka7tsem/Howe Sound, and the rest of the planet for that matter, are now compounded by the more recent affects of global climate change and ocean warming. Today, government led initiatives, work by research institutions and actions by concerned citizen scientist community groups, and First Nations are showing hopeful results in rejuvenating Átl’ka7tsem/Howe Sound and re- establishing impacted habitat, but it is a very slow process. A century of neglect and impact cannot be solved quickly. Tidal exchanges in Átl’ka7tsem/Howe Sound result in an average rise or fall of about 4 metres with current speeds rarely exceeding two knots. The large, intricate surfaces of a reef area, whether natural or man-made, interacts with tidal currents, interrupting, dispersing and redirecting them and delivering nutrients necessary for existing life and also transporting myriad planktonic or juvenile forms of marine life preparing to settle in a more permanent habitat. There is an abundance of seed material floating in the air (just ask any hay fever sufferer!) and planktonic material carried by currents in the ocean just looking for suitable habitat, and nature hates a vacuum so if an empty space is created, whether it is deep in the forest or deep in the ocean, nature will do its best to fill it. Unfortunately, there is probably more seed material than there is suitable habitat and not everything grows everywhere but the placement of a large artificial reef structure provides added opportunity for suitable habitat. Like animals and plants on land, marine plants and animals have specific needs and tolerances as to depth, current interaction and places to hide from prey and predators, and things will not thrive where the conditions are not conducive to their specific needs for survival. It has been suggested in order for artificial reefs to increase production, they need to provide habitat that can improve larval settlement, growth and survival. The high vertical relief of vessel-reefs may increase settlement of juveniles by extending habitat into areas higher in the water column, possibly attracting larval marine life closer to surface waters (Polovina, 1 Restocking efforts of Black rockfish in Howe Sound are showing gradual but promising results. 2 1991, Rilov & Beneyahu, 2002). With the wide variety of habitats offered by a large, intricate and convoluted structure such as a ship with its myriad nooks and crannies at a variety of depths, the chances are good that there is a niche for most species. 2 – BACKGROUND The Artificial Reef Society of British Columbia (ARSBC) is a Vancouver based, volunteer driven, non-profit, registered charity formed in 1989. The society’s goal is to create, place and establish environmentally and economically sustainable human made reefs for the protection and enhancement of affected sensitive marine habitats while also providing unique opportunities for qualified SCUBA divers. Over the past 30 years the ARSBC has successfully placed nine

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