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We occasionally publish articles in SpruceRoots magazine, a journal providing perspectives and promoting discussion on issues that affect Haida Gwaii. Please find links to these articles for reading on the website or for download from the SpruceRoots website ~ www.spruceroots.org. Be sure to look through the SpruceRoots stories for other articles on marine issues, including salmon farming and BC offshore oil and gas.
Discover. To be the first to find or find out about. The first hint of something strange surfaced in 1984 during a sea-floor mapping exercise in Hecate Strait. Geological Survey of Canada (GSC) scientists observed through sonar imaging, unexpected permeable bumps over huge areas of the sea floor. Similar acoustic anomalies, described as an "amorphous, irregular seismic signature having no coherent internal reflectors," were observed again in 1986, this time during a survey in Queen Charlotte Sound. In 1987, GSC scientists Kim Conway and Vaughn Barrie discovered the sponge reef. It was "something that succeeded even our expectations," says Conway. Unique. Being the only one of a particular type. It's unique and it's big. It is the only living bioconstruction of its kind known in the world. And it lives in our backyard - four sponge reefs, around 9,000 years of age, 700 kilometres squared in combined surface area and up to 18 metres high, all under 150 to 250 metres of water. The posts and beams of the sponge reef are siliceous sponges of the Order Hexactinosa, providing the rigid framework necessary for reef formation. Like the building of coral reefs, young sponges attach and grow upon the older generation, laterally and vertically extending the reef. The reef complexes exist in three continental shelf troughs from Hecate Strait south to Queen Charlotte Sound. The northernmost reef sits 10 nautical miles offshore from Banks Island; the southernmost is 50 nautical miles north of Vancouver Island. Extinct. Of an animal or plant species having no living representative. Siliceous sponge reefs were thought extinct. Prehistoric sponge reefs stretched in a discontinuous belt 7000 kilometres - three and a half times longer than the Great Barrier Reef off northeast Australia - across the northern Tethys to the margin of the Atlantic Ocean at a time when part of modern Europe, as we know it, was under the sea. Today, fossilized outcrops extend across Romania, Poland, Germany, Switzerland, France, Spain, Portugal, off Newfoundland and Oklahoma. The sponge reef on our coast is a living organism ecosystem that will provide insight into the Jurassic paleoenvironment which supported the vast Tethys sponge reef. The first recorded hexactinellid sponges shared oceans with coelacanth fish (thought extinct until discovered off the coast of South Africa in 1938) during the Devonian Period 400 million years ago. Sponge reef distribution climaxed in the late Jurassic Period 140 million years ago, with the formation of the northern Tethys reef. This fossilized sponge reef from the Age of Dinosaurs is the largest bioconstruction ever known to exist. Following the Jurassic Period, sponge reef distribution dramatically declined to apparent extinction during the Cretaceous Period 65 million years ago. Science. The systematic study of the nature and behaviour of the material and physical universe, based on observation, experiment, and measurement, and the formulation of laws to describe these facts in general terms. Up until 1987, sponge reef science was limited to description and study of the fossilized northern Tethys sponge reefs and similar areas. Paleontologist Manfred Krautter, at the University of Stuttgart in Germany, spent years studying the fossil sponge reefs of Spain, Germany and Portugal. But, in 1987, the dinosaurs came to life. Underwater photography in Hecate Strait captured live irregularly-shaped sponges, with random fingerlike projections and a large central cavity. Over two years, GSC scientists map-ped the location and extent of the sponge reefs; mollusc shells embedded in core samples allowed the reef to be aged by carbon-dating. In 1999, Canadian and German scientists, including Conway and Krautter, embarked on a joint research program to unlock to secrets of the sponge. Funded by the Geological Survey of Canada and the University of Stuttgart, the Canadian Coast Guard vessel John P. Tully cruised over the reefs. Aboard were a team of scientists and sophisticated geophysical surveying equipment. A Delta submersible (equipped with underwater still and video cameras and a mechanical maneuvering arm with a grab sampler and super sucker slurp gun) provided images, picked up specimen rocks and sponges, and excavated sediment. At one point during the survey, it took five hours, traveling at speeds of 1 to 2 nautical miles per hour, for the submersible to cross the reef. Forty hours of videotapes and nearly two thousand 35mm slides later, the scientists fastidiously identified species and their abundance through the sampled sites. Marine organisms noted to date include annelid worms, bryozoans, bivalves, gastropods, spider crabs, box crabs, shrimps, prawn, sea stars, urchins, brittle stars and rockfishes. Initial observations suggest that the sponge reef provides benthic habitat for a wide variety of organisms and that the local ecology of the reef is different than that outside the reef area. For the first time anywhere, hexactinellid reefs were studied by direct observation. How did these sponge reefs form? First, a special set of environmental
circumstances provided good attachment sites, allowing the sponge to
grow. About 15 to 13 thousand years ago, when glaciers covering much of
Hecate Strait and Queen Charlotte Sound began to melt, sea levels were
about 150m lower than they are today. Icebergs scoured the continental
shelf, leaving marks at modern depths over 250m. During the Holocene
Period 9,000 years ago, sponge reef construction started on
iceberg-ploughed berms of coarse gravel. Third, there was a balance between sediment coming into the area and sponge survival and growth, allowing the reef to persist and develop over geologic time. In a process similar to sand and silt dropping out of river water in lower velocity backeddies and off-channel areas, sediment deposits out of sea water as it travels into lower velocity eddies created by the rough surface of the reef. The Building Blocks Sponges of all kaleidoscopic shapes, sizes and colours belong to the Phylum Porifera. Over 10,000 species are known worldwide, from the equator to the poles, from shallow tidepools to deep ocean trenches. Largely unchanged in basic form since the Devonian Period, hexactinellid (glass) sponges are characterized by their siliceous spicules (inanimate crystals of silica or calcium carbonate) which consist of six rays intersecting at right angles (similar to a toy jack). The spicules (hexactines) are interwoven throughout the sponge body. Although numerous sponge species exist on the reef, three form the framework of the reef: Aphrocallistes vastus, Chonelasma calyx and Farrea occa. Sponges are distinct, having the most simple body structure of all multi-cellular animals. A sponge is typically composed of an outer layer (cortex) and an inner layer filled with spicules and organic fibres. Water, the lifeblood of the sponge, is drawn into the organism through innumerable small openings (ostia) which perforate the outer surface, acting as gateways to a labyrinth of internal canals and chambers. Lining the walls of the labyrinth, millions of flagellated cells beat vigorously to sweep water through the sponge body, simultaneously trapping food particles for energy. Much like blood in our circulatory system, water also transports oxygen to internal cells while removing cellular waste products. In the reef sponges, filtered water is expelled through a central cavity (osculum). Incredibly efficient filter feeders with a predilection for bacteria and other organic debris, a typical sponge can filter four to five times its body volume every minute. At this rate, a basketball-sized sponge would process several thousand litres of water each day. A sponge reef complex covering an area of 700km2 two and a half times the size of Louise Island - with a presumed average height of 0.5m, would therefore filter 1.75 trillion litres of sea water per day - roughly equivalent to 6 times the volume of Yakoun Lake or 500 times the daily discharge volume of the Yakoun River watershed! Construction Individual sponge mounds, which initially look symmetrical and circular, develop irregular shapes as suspended sediment settles on the mounds through slowing of tidally-driven currents. As sediment accumulates, individual and coalescing mounds develop and tend to elongate in the direction of prevailing seabed currents. These reefs represent the only significant post-glacial deposits throughout much of the continental shelf since negligible amounts of sediment settle outside of the sponge reefs. Interestingly, the marine sediments trapped in the reef contain up to 3% organic carbon as high as values found in the sediments of productive estuaries. Today, the reef occurs both as mounds (bioherms) and as sheets (biostromes). The bioherms are steep-sided formations up to 18m six stories high; The more extensive biostromes are several metres thick and cover many square kilometres one square kilometre encompasses 75 typical city blocks. Any given reef complex is composed of bioherms and biostromes of varying shapes, sizes and densities. Unlike many sponges which are reduced to a mat of loose spicules once their organic matrix has decomposed, dead hexactinosan sponges retain their shape as they are buried by clay-rich sediment. This burial process protects the siliceous skeletons from dissolving in sea water. Building on the skeletons of previous generations, live sponges can be over a metre high. With an estimated maximum growth rate of 1 cm per year, these sponges are over 100 years old! The Building Lynn Lee is the Haida Gwaii local coordinator for the World Wildlife Fund.
For over 7,000 years, coastal First Nations people along the British Columbia coastline harvested abalone for food, decoration and currency for trade. Harvesting was by hand picking in the intertidal at low tides and by using a two-pronged spear able to reach down 6 feet below the surface. Diving was not known as a harvest method and thus, only the intertidal and a very small portion of the upper subtidal abalone population was exploited by traditional First Nations fisheries. In the early days, Haida people traveling to the Skeena and the Nass Rivers had also sold dried abalone to the Chinese. For perhaps 100 years, but certainly since the advent of SCUBA (Self-Contained Underwater Breathing Apparatus) in the 1950s, a small recreational fishery for abalone has existed. Prior to the abalone harvesting closure in 1990, most areas of the B. C. coast were open to a daily bag limit of 12 abalone over 100mm shell length. Around 1910, the first recorded commercial abalone fisheries in BC took place around Haida Gwaii, with canning stations at Jedway Bay and Rose Harbour, and drying stations at Murchison Island. At the same time, canning activities were also reported in Bella Bella. By 1913, all but the Jedway Bay cannery was closed, with Jedway continuing sometime past 1926. Between 1913 and 1952, little is known about the fishery, although harvest levels were suspected to be quite low, ranging from 6.4 tonnes in 1922 to 30.6 tonnes in 1928. With the advent of SCUBA in the early 1950s, commercial landings of abalone became more consistent. Between 1952 and 1971, an average of 7.71 tonnes of abalone was harvested every year, with a maximum landing of ~58 tonnes in 1964. During this period, the product was sold on the domestic market, fresh to restaurants and seafood stores, bringing prices between $0.15 per kg in 1954 and $0.92 per kg in 1970. In the 1950s, much of the abalone harvest occurred on the south coast. In the 60s and early 70s, about half the harvest came from each of the north and south coasts. About thirty years ago, the large-scale commercial harvest of abalone began. Abalone was one of many "developing fishery" species being harvested by the BC diving fleet and fishermen were testing the waters for monetarily valuable species. Prior to 1976, the harvest was open to anyone who had a personal fishing license and, after 1968, an unlimited "C" license (granted to anyone having a vessel with approved fish-holding space). The fishery was regulated with only a minimum size limit, the philosophy being that this limit was sufficient to sustain the abalone population. Precipitated by numerous factors including restricted access to salmon and roe herring fisheries (causing fishermen to look for new fishing opportunities), unrestricted access into abalone and other "developing" fisheries (including geoducks, red urchins and prawns), developing technology moving from day-boats to freezer-boats (allowing fishermen to fish more remote areas for longer periods of time) and increased demand and prices from Japan (between 1972 and 1976, the landed value increased 3-fold to $3.14 per kg), abalone landings reached a record high of 274 tonnes in 1976. In less than a year, the commercial harvest took more than the 4 previous years combined (1972 to 1975) and possibly more than the 62 years before that (1910 to 1971). In 1976, fishery managers realized that minimum size limits were not enough. Abalone was in demand and the price on was rising rapidly. Suddenly, abalone was a valuable commodity. Over the next 2 years, fisheries management attempted to control abalone harvest levels to no avail. Despite the introduction of limited licensing, limited number of divers, reduction in fishing season, minimum size limits, changes in harvesting procedures and requirements for activity log books, landings increased unabated. The 1977 landings totaled 428 tonnes coastwide, over 8 months of fishing from 29 licenses, with almost all the catch coming out of North Coast waters. In fact, since 1976, consistently over 75% of the landings occurred from the North Coast and much of that was harvested from Area 1 (north Graham Island) and Area 2E (east Moresby Island) around Haida Gwaii. Attempting to reduce the catch to ~255 tonnes in 1978, DFO opened the fishery to 27 licenses for only 3 months resulting in a total catch of 433 tonnes! Further management action was taken, limiting the fishery to a total overall quota and dividing the total quota equally among all 26 license holders, resulting in Canada's first Individual Vessel Quota (IVQ) management system. To ease the fisheries into this new regime, the 1979 season was divided into 2 phases: 113 tonnes was taken as an open fishery which lasted 18 days and the remaining 113 tonnes, equally divided into IVQs, lasted almost 7 months. The pressure for each individual fisherman to get as much as possible as fast as possible was relieved. The pressure on the BC abalone population, however, was not relieved. Fishery independent stock assessment of the abalone population was initiated after the distressing record harvest in 1976. Prior to 1976, only anecdotal information was available. Rough estimates made in the early 1980s indicated that the density of abalone decreased by 60 to 90% in harvested areas of the North Coast between 1976 and 1978. Later estimates indicated an 80% overall decrease in density along east Moresby Island between 1978 and 1984. Although patchy distribution of abalone make the stocks difficult to assess, it was clear that a precipitous decline in population had occurred since the start of assessment in 1976. The serial depletion of B. C. northern abalone stocks was underway. After 1979, quotas continued to be reduced year
after year as prices continued to increase. By 1987, the overall quota
for the fishery was set at 47 tonnes and the price had reached over $18
per kg. In December 1990, Fisheries and Oceans Canada (DFO) perceived a
problem. Under threat of abalone population collapse, DFO closed
commercial, recreational and First Nations fisheries for northern
abalone, in hopes that the population would naturally rebuild. Today, the legal harvest of northern abalone remains closed along the British Columbia coast. Despite 10 years of fishery closure, continuing stock assessment by DFO shows no apparent increase in the abalone population around Haida Gwaii. Decreasing abalone densities and declining numbers of monitoring sites showing abalone presence suggest that serial depletion of larger formerly legal-sized abalone continues today. Clouded by an illegal harvest of abalone whose history is as long as the closure and whose breadth has been estimated at up to 5 times the former legal quota, solid explanations for the continued population decline remain elusive. Possibilities? Overharvesting, poor or periodic survival of juveniles, natural predation, environmental factors affecting survival of one or many life stages, poaching and lack of enforcement, and reduced kelp bed areas since elimination of sea otters. In time, the answers may become clear In the meantime, restoration of a healthy marine environment and community stewardship of remaining abalone populations remains key to their survival.
Abalone Sex
· Febuary 2001 The life of an abalone begins with conception. Unlike our familiar concepts, abalone conception doesn't begin inside a mature animal it occurs in the seawater column! Abalone are broadcast spawners adult abalone of separate sexes release millions of eggs and sperm into the water and there it must meet. A rather optimistic way to get together in all that fluid space! As you can imagine, many eggs and many sperm must be released at the same time in the same place for fertilization to succeed. To help the process along, when abalone spawn, mature adults congregate in the shallow subtidal, gathering in relatively high densities on the peak of the highest rock in the area - being higher when sperm is released gives eggs a greater chance of encountering it. Adding to the excitement, they sometimes balance on top of one another up to 6 abalone tall all to get that extra high! In BC, spawning tends to occur between June and August. Within several days, the eggs hatch, beginning the free-swimming larval phase of the abalone life cycle. The first stage is a very small larvae called a Trochophore, which does not need to eat because it is equipped with its own yolk sac for energy. The trochophore larva moves upwards in the water column, attracted to light, thus increasing its travel opportunities on ocean currents this is really the abalone's only chance to visit wider parts of the neighbourhood. In a couple more days, a larval shell starts to form and the trochopore transforms into the second stage of larval life as a Veliger that is no longer attracted to the light. Within 5 to 8 days of hatch, the larva undergoes metamorphosis, turning into a very very small abalone ready to spend life roaming the rocks. When juvenile abalone are ready, chemical signals emitted from particular types of algae, including encrusting red coralline algae, compel the larva to undergo metamorphosis and settle. Juvenile animals less than one or two year old tend to be found in crustose red algae gardens generally deeper than adult animals. It is thought that juveniles settle in deeper water usually deeper than the kelp zone down to 15m deep. As they grow, abalone migrate upward such that most adults are within 10m of the water surface. As juveniles, abalone tend to be cryptic, hiding under rocks and in crevices for most of the day, as they get larger they tend to hide less such that by the time they reach 100mm in shell length, they are all "exposed". The story is that younger smaller abalone have to worry more about being eaten than their larger friends and therefore, the smaller animals need to hide to survive. When they are very young and small, juvenile abalone must eat very tiny plants. Grazing first on diatoms (single-celled phytoplankton) and bacteria which collect on the surface layer of encrusting red coralline algae, the abalone moves on to scrap the surface layer of the coralline algae. By 6 to 13 weeks of age, crustose red algae dominate the abalone food palette. As they grow larger, abalone tend to move around less, preferring to graze less and spend more time trapping drift algae for food. But not just any food will do! Experiments show that as adults, abalone prefer bull kelp (Nereocystis) and giant kelp (Macrocystis) over other kelps. When an abalone will fit into size 8 shoes is not as consistent as you might think. The growth rates of abalone are highly variable, depending on numerous environmental factors such as the quantity and quality of available food, the frequency and magnitude of storm conditions (exposure). At each extreme, abalone fortunate enough to settle in a protected kelp forests with plenty of high quality drift algae will tend to grow much faster and to a larger maximum size than those who settled in a high exposure kelp forest with little drift algae. Interestingly like tomato plants taken from outdoors, placed in a greenhouse and fertilized - abalone will increase in growth rate and size when moved from difficult to more favorable habitat conditions. Unlike the aging of trees, salmon and geoducks, the age of abalone cannot be determined by counting growth rings. Although abalone do have seasonal growth cycles for example, little shell growth during periods of high egg and sperm production annual growth ring formation is not consistent. Measuring, tagging and re-measuring of individual animals a year later has been the only reliable indicator of natural growth rates. From these data points, growth curves generated for abalone suggest that it takes at least 6 years, and more often 7 or 8 years, for an abalone to reach 100mm in shell length (significant because this was the minimum size limit of the commercial and recreational harvest). By 3 years of age (~50mm length), gonads are maturing and by 4 years of age, individuals are generally spawning. Like many long-lived slow-growing animals, though, the level of egg production increases rapidly with size after maturity, reach a climax age then decline in egg production beyond that. The largest northern abalone ever documented was 165mm in length, at least 15 years old and perhaps up to 50 years old!
Everything You
Wanted to Know About Abalone but were Afraid to Ask ·
Feburary 2001 The first people of Haida Gwaii/Queen Charlotte Islands call them by many different names, among them gaalahlyan, galgaahliiyaang and galguuhlkyan. In Haida legend, it is said that the northern abalone descended from the northwestern toad during k'áy gang, the "Time of the Raven." For thousands of years, they harvested northern abalone for food along rocky intertidal shores all around Haida Gwaii. They were traditionally harvested by hand picking animals exposed in the intertidal at low tides and by spearing animals down to six feet below the water surface. Traditionally, the two-pronged seafood spear, kíit'úu, was made by lashing (using spruce root twine) two sharpened pieces of huckleberry stem to each side of a long pole made of spruce or red cedar. Collection of abalone using this spear required practice and skill. If the animal was speared and not twisted off the rock in the same motion it might adhere to the rock with its strong foot and be hard to retrieve, if the animal was speared too lightly, it might be knocked off the rock and fall away to depths beyond reach. Once in hand, the foot of the abalone was removed and eaten raw - sometimes the gonads, ts'iikál, were also eaten. Abalone shell was used for decoration and currency, although Skidegate Haida preferred to use the shell of gwúlxa, the California red abalone, to the indigenous northern abalone. To science, they are marine snails of the Phylum Mollusca, taxonomically Classed Gastropoda, literally translated as "stomach foot" - quite a culinary distinction. Their scientific name is Haliotis kamtschatkana. Abalone are prevalent throughout the northeastern Pacific Ocean, found from the northern tip of Sitka Island in Alaska, south throughout British Columbia, and down through the states of Washington, Oregon and California, and into the Baja. They are also the northernmost species of all the haliotids (over 90 species are described worldwide). In Canada, they are commonly known as the "northern" abalone and in the United States, they are called "pinto" for their mottled white appearance.In the waters of BC, Alaska and Washington, northern abalone are most abundant and do not share their space with other abalone species. In California, they share waters with the red, pink, white, black, green, threaded and flat abalone.
The dynamics of abalone populations remain an enigma to science. They are a mysterious species, they are difficult to age, individuals growth rates vary wildly depending on conditions where they live, their reproductive success rate is not known, their survival rate through different life stages is unknown and they like to keep people guessing about how long they live. For thousands of years, northern abalone populations co-existed with the voracious sea otter, a formidable predator that can eat one-third of its body weight a day. Although it seems a contradiction, they lived together in a harmony of balance. The relationships are complex and not fully understood, but in general terms, abalone provided sea otters with one of a kaleidoscope of invertebrate and fish food sources and sea otters provided abalone and other creatures with ample kelp forests for shelter, food and reproduction by controlling populations of grazing sea urchins. About 100 years ago, the sea otter was hunted to extinction along the shores of Haida Gwaii. In the wake of their absence, sea otter prey species, including abalone and red sea urchins, thrived and multiplied. Over time, the subtidal extent of kelp beds decreased as sea urchin grazing proceeded unabated. About 50 years after the sea otter disappeared, another predator arrived, armed with funny looking rubber suits, masks and prying bars. Abalone populations succumbed under commercial harvesting pressure. At first, the commercial harvest took hundreds and thousands at a time, then starting in 1976, hundreds of thousands were processed year after year. In three short years, the abundance of abalone along the BC coast was reduced by a rough estimate of 60 to 90%, marking the beginning of the collapse of BC's northern abalone population. Today, northern abalone live with the natural dangers of hungry cabazons and wolf eels fish with nightmare inspiring faces stealthy sun stars, Pacific octopus, rock crabs, and ravens and river otters at low tide. The generally sedentary lifestyle of the abalone is disturbed when they do a little break dance to run from voracious sunflower stars! Less naturally, the odd rubber-suited poacher adds additional challenge to the survival of the species. On April 23, 1999, the BC northern abalone earned the great distinction of being the first-ever Canadian marine invertebrate to be designated a "threatened" species by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). No other spineless marine creature will ever fill those shoes! In official terms, this means that the species is "likely to become endangered if limiting factors are not reversed". Today, northern abalone survive in numbers much reduced by many factors, man-made and environmental the short and sad history of commercial fishing, large-scale illegal fishing following abalone fishery closure in 1990, decline in rocky shore kelp bed areas since elimination of the sea otter, changing ocean currents and temperatures. Whatever the combination of factors, the accelerated decline of the abalone population has largely been a consequence of their value as a commodity in world economic markets. The future of BC's northern abalone is in the hands of local communities to respect and value beyond monetary returns. Abalone are part of tradition and culture, ways of being and living with respect for the natural world they are a vital part of a healthy marine community, a natural treasure.
Deep Blue -
facing the ocean of issues in the marine environment · July
2002 It is hard to appreciate that beneath the ocean
waves there is an intensity of life that puts this terrestrial world to
shame. For many, even though we are surrounded by saltwater, the ocean
is just something we look at and admire - its changing colour, the
patterns of wave and wind that move across its surface. Some people do
have a strong connection to the sea by virtue of culture, livelihood or
the time spent as children at the seashore. But by the same token, many
don't think about what goes on beneath its surface, for in those deep
blue waters, spineless creatures, fishes and mammals thrive in
ecosystems that are the most ancient on the planet. |
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