1990	WINTER (November)	Marbled Murrelets in the Walbran Old Growth Strategy Project Robson Bight and Tsitika Valley Update Kitlope Valley Stickleback Research in the QCI Biological Diversity: What's it all about? Part 1
1990	SUMMER (July)	Development underway in the Klaskish News from Rain Forest Grizzly Valley, the Khutzeymateen The Mysterious Marbled Murrelet Cleland Island and Baeria Rocks ERs Nimpkish Island's Tall Trees Oak Groves on Hornby Island
1990	SPRING (February)	Editorial: New Decade: New Goals Sea Otter Research in ER 109 Fencing Mt Tzuhalem ER: a Co-operative Effort Rhododendrons: Asian Images

WINTER 1990

Stickleback Research in the QCI

My biological investigations on the Queen Charlotte Islands (QCI) began in 1967. Since 1975 I have focussed on evolutionary relationships between the giant stickleback fish and diving seabirds at the Drizzle Lake Ecological Reserve (ER 52) and, with my colleague Sheila Douglas, studied the reproductive and foraging biology of the Red-throated loon. During this period, I have expanded my attention to include biological and limnological sampling from 380 lakes throughout the QCI, including those on and in the vicinity of the reserves at Tow Hill (ER 9) and Rose Spit (ER 10) and the Krajina reserve (ER 45) on the west coast of Graham Island. The research is diverse. Many investigations are ongoing and others are in various stages of completion. Funds from Friends of Ecological Reserves have allowed me to complete several sections of the research.

One of the unusual aspects of the Drizzle Lake stickleback is the exceptionally large adult size of the fish. Stickleback typically range from 40 to 70 mm. In length, but at Drizzle Lake they reach 110 mm. The reason for this gigantism is unknown. From analyses of trout stomachs and monthly estimates of trout numbers in the lake, I determined that adult stickleback represent only four per cent of the total stickleback eaten yearly by cutthroat trout. This suggests that adult stickleback are too large for trout to swallow. Given, however, that adult stickleback represent only about four per cent of the total numbers of the species in the lake, the trout may simply be taking stickleback in proportion to their abundance. To eliminate this possibility and test whether the giant stickleback were protected from trout as a result of their size, I carried out a series of predation experiments by offering trout of different sizes a range of stickleback also differing in size. With a video camera and the help of various assistants (Bristol Foster, local high school students), I was able to get data on 1600 separate feedings, from which I determined which ones got away after being captured, which got eaten and how lot it took to swallow the stickleback.

Some results were expected and satisfying, others puzzling. Virtually all small stickleback, even with their large spines, were eaten, while the giant stickleback were largely immune from predation by even the largest trout. While it took only several seconds to swallow a small stickleback, trout chomped on giant stickleback for up to 20 minutes before giving up and spitting out the stickleback, which swam away, somewhat scared and scarred but surviving. It was difficult to get a trout to follow through with an attack on an adult stickleback. This would be tremendously useful for the stickleback, which builds its nest in shallow waters and has to defend the territory around from all intruders. There are 21 species of stickleback predators at Drizzle Lake, and trout, which consume the most stickleback, may be the most important predator that has led to the evolution of giant adult sizes.

This work is published in the Canadian Journal of Fisheries and Aquatic Sciences (47: 1194-95, 1990) and in Copeia (in press).

A second study completed last year with my colleague Dr. Johnny Buckland-Nicks of St. Francis Xavier University, Antigonish, NS, concerned a population of spine-deficient stickleback in Rough Pond, on the district log adjacent to Tow Hill. Several years ago I discovered that the stickleback in this small pond contained a novel covering of cysts over the entire body and head. Remarkably, these cysts were photosynthetic and appeared not to harm the fist. After a great deal of work on the electron microscope and with further assistance of Dr. F. J. R. Taylor (in Oceanography at UBC), we have now identified these as a new species of dinoflaggelate without any clear affinities to any known dinoflaggelate. Nothing comparable to this association has been seen throughout North America or Europe, and we are still not sure of the significance of the finding. Some peculiar limnological characteristics of this muskeg pond and surrounding area may have resulted in this association, or, possibly, the population of stickleback is a relic from preglacial periods. This possibility, which I discounted until recently, may be the most likely interpretation. I am continuing plankton samples of this pond and Johnny is culturing the dinoflaggelates in an effort to find each of the stages in the complex life cycle.

This work is published in the Canadian Journal of Zoology (68: 667-671, 1990) and in Journal of Phycology (in press).

Many species on the Charlottes—the black bear, the short-tailed weasel, the Saw-whet owl and the stickleback—have features distinctive from their relatives on the mainland. Did they separate in the post-glacial era (less than 12,000 years ago), or did they separate earlier and survive in an ice-free refugium, as various scientists have postulated but never proven? A breakthrough in molecular technology, restriction endonuclease analyses of mitochondrial DNA, provides the opportunity to answer this question realistically.

My graduate student, Pat O-Reilly, has looked at 12 stickleback populations, including the giants at Drizzle Lake, the spine-deficient at Boulton Lake and those at Rouge Pond with their unusual dinoflaggelates. Several findings emerge from this difficult and expensive study. The giant stickleback at Drizzle Lake and the spine-deficient stickleback at Boulton Lake have mitochondrial clones virtually identical to marine stickleback near the Charlottes, which suggests that these unusual stickleback have a very recent, post-glacial original. Morphological evolution can proceed very fast, and this suggests that some of the other endemics on the Charlottes may also be recent in origin. Alas! Nothing is ever so simple: the mitochondria of the Rouge Pond stickleback and of three other populations on the northeastern tip of the Charlottes are highly divergent from all other stickleback. Using the “molecular clock” developed for mitochondrial DNA, it would appear that these fish may have separated from all other stickleback around the Charlottes about 1.2 million years ago! The northeastern corner of the Charlottes may have been an ice-free refugium for much of the Pleistocene era, when repeated glacial advances occurred over the rest of the Charlottes and the BC mainland. I am dubious of this conclusion, because the area is of low elevation and appears to be underlain by glacial outwash moraine. The molecular divergence is, however, so great that extended isolation is the best available interpretation for these mitochondrial data. If true, it means that there may be other ancient genetic lineages among the endemic plants, birds and mammals that live on the Charlottes. Molecular comparisons of these with those on the mainland would tell us a great deal.

These results were presented at a congress at the University of Maryland in July 1990 and are being submitted to Science.

Tom E. Reimchen, Ph.D.

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Biological Diversity: What's it all about? Part 1

(Excerpt from an article by Dr. Jim Pojar in the Spring 1990 issue of Bioline, published by the Association of Professional Biologists of BC)

Biodiversity is the variety of life in an area, which could be as small as a decaying log or as large as the biosphere. The full range of natural variety includes the genetic diversity of populations, the number and kind of different species, the distribution and abundance of plant and animal communities and of ecosystems, and the myriad of ways in which living things actually live and interact. Genetic diversity involves genotypic variation within a taxon. Species diversity is a measure of the richness of different species, both in numbers and relative abundances. Ecosystem diversity is a landscape concept. And functional diversity transcends all three of these levels of organization and reflects the variety of processes whereby organisms interact with other organisms and with their physical environment.

Why Conserve Biological Diversity?

Let me count the whys:

1. It’s going fast. Biodiversity is being reduced at a rate without precedent in human history. During the next few decades, human activities will cause the extinction of more species than at any time since the dinosaurs disappeared 65 million years ago.

2. For its intrinsic value. This is the ethical, deep-ecology view, that all living things have the substantive right to exist, and it would be presumptuous to assume that some species, especially our own, are more valuable and deserving of attention than others.

3. Biodiversity is also valuable as a source of intellectual and scientific knowledge, recreation, and aesthetic pleasure.

4. Humans depend on plants, animals, and micro-organisms for food, medicine, shelter, and other products. Reduced biological diversity could mean losses of resources for research, agriculture, medicine and industry. In this regard, it is worth noting the concern of the International Society of Chemical Ecology, a group not renowned for its environmental awareness, over the implications of species impoverishment to the future discovery of useful natural products. A resolution passed in 1989 draws attention to our dependence on naturally occurring chemicals, urging conservation measures to stem the tide of species extinction, and calling for much more chemical “prospecting” to discover more of these precious resources.

5. Reduced biodiversity could also harm the functioning of ecosystems and critical ecosystem processes that moderate climate, govern nutrient cycles and soil conservation, control pests and diseases, and degrade wastes and pollutants.

6. Maintaining existing natural diversity makes sense because we cannot predict which biological resources will be most important to future needs.

7. It could be that systems with greater biological diversity are more stable in the long term, are more resistant to disturbances, to destructive oscillations in populations, and to biological invasions.

This article will be continued in the next issue.

Jim Pojar, Ph.D, M.Bio

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SUMMER 1990

Nimpkish Island's Tall Trees: Ongoing Damage in Nimpkish Island Ecological Reserve

A. C. Carder, a Victoria naturalist with a long-time interest in tall trees, wrote to pass on his impressions from a visit last summer to the Nimpkish Island Ecological Reserve, “that tall stand of Douglas-firs and other species on a small island straddled by the Nimpkish River.

“I was curious to know what protective steps have been taken to preserve the Nimpkish trees from bank undercutting and wind-throw. At the time of my previous visit damage from both factors was taking place, and I was told by the environment minister that preservation measures would be undertaken. What I saw saddened me. After writing to the minister twice, I at length received a reply saying some work had been done on bank stabilization and more would be done when funds became available. It may be possible to prevent the stream-side erosion that has been brought about by large clearcuts up the Nimpkish Valley. About wind-throw and other injury wrought by wind, I’m not sure what can be done. When I first visited the Nimpkish Trees, other virgin stands across the fiver offered protection, but they have been clearcut, exposing the trees on the island to the full force of the wind. I think this will in time have a pronounced effect on these threes, and the whole object of preserving them will be defeated. A lot of public money was put into acquiring the Nimpkish Trees. I have not viewed the Carmanah spruce forest, but from what I have seen at Nimpkish, even clearcutting a low percentage of the stands will lead to considerable damage to the rest.”

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SPRING 1990

Sea Otter Research in ER 109

Sea otters (Enhydra lutris) once inhabited the N.E. Pacific from Baja, California to northern Japan. Much prized for their thick water repellent coats, sea otters were hunted to near extinction from the late 1700s to the early 1900s. In 1911, a treaty prohibiting the harvest of fur-bearing marine animals from the west coast of North America was signed to protect dwindling numbers of marine mammals. By 1920 the only remaining populations of sea otters could be found in the Aleutian Islands, Prince William Sound, the Queen Charlotte Islands (this population subsequently went extinct), and California. From 1969 to 1972 sea otters from Amchitka Island and Prince William Sound were reintroduced into British Columbia. A total of 89 sea otters were translocated in a series of three transplants to Checleset Bay on the west coast of Vancouver Island.

Since this introduction BC’s otter population has grown. Survey work indicates that the otter population has grown at a rate of approximately 17 per cent per year, and now stands at 400-500 animals. In 1973 Ecological Reserve 109 was established to protect the sea otters, their environment and to permit opportunity for long-term research and public education. This area, Checleset Bay, is now completely occupied by sea otters and accounts for about 350 of BC’s 500 otters.

For the past three years I have been studying BC’s sea otter population. This work has focused on the sea otter population itself and how sea otter foraging is affecting the community in which they live.

Sea otters lack the thick blubber of many aquatic mammals and depend on their dense fur for insulation. As a result sea otters have a high metabolic rate and must eat approximately one quarter of their body weight in food each day, thus an adult otter may eat up to 12 kilograms of urchins, abalone, clams, crabs and mussels each day. By reducing the number of invertebrate herbivores, particularly sea urchins, sea otters increase the abundance of kelp and other fleshy seaweeds, which has a tremendous effect on the nearshore ecosystem. Kelp provides a rich source of detrital and dissolved organic matter, alters the nearshore environment by damping onshore wave motion and provides shelter and nursery grounds for many species of fish.

The results of this study show that sea otters are having a profound effect on the nearshore community in BC in areas where sea otters occur, urchins and immediately into areas that have been cleared of urchins by otter foraging. By sampling pterygophora throughout the sea otter’s range, the age of the plants can be used to indicate when the sea otters first arrived in an area, and subsequently how fast the population has expanded over the last 20 years. This work was stared this year but the results have not yet been analysed.

For the past three summers sea otter surveys have been conducted. At present the sea otters are located in two distinct areas, [in Checleset Bay] from the Brooks Peninsula to the village of Kyuquot (ER 109) and from Ferrer Point to Nootka Light on Nootka Sound. The population appears to be doing well despite the effects of the Nestucca oil spill this past winter. Perhaps the most exciting discovery this summer was made by a crew from West Coast Whale Research Foundation. While filming at Lawn Point in Quatsino Sound a third population of otters was found about 40 miles north of the Brooks Peninsula. Approximately 350 animals were counted in Checleset Bay, and 140 in the Nootka Sound. There are an unknown number at Lawn Point. Females with pups formed a substantial portion of all the otter groups.

Other shellfish species are largely absent and huge underwater forests of kelp flourish. Adjoining areas not inhabited by sea otters are remarkably different; sea urchins dominate the landscape and the bottom is covered with a crust of pink grazer resistant coralline algae.

One species of kelp may prove to be very useful for determining how rapidly the sea otter population has expanded geographically. Pterygophora californica is a stalked kelp that lays down annual rings, much like a tree. Pterygophora grows to a height of 2 metres and forms a subcanopy beneath the canopy forming Bull kelp (Nereocystis) and Giant kelp (Macrocystis). As the sea otter population expands to occupy its historic range, controversy can be expected. The sea otters diet of commercially important shellfish brings it into direct competition with humans. At the same time, its easily damaged insulating fur makes it extremely susceptible to marine pollution, much as its fur was its undoing in earlier times. While controversy and politics nay surround the sea otter, it would appear that it has returned to BC …. to stay.

Funds for this research were obtained from: Friends of Ecological Reserves, the BC Ministry of Parks and Recreation, the Vancouver Public Aquarium and the Department of Fisheries and Oceans.

Jane Watson

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