1991	SUMMER (August)	Editorial: Our Disappearing Ancient Forests Megin River Explorations Transient Killer Whales Predation Old Growth Deferral Shell Game Why Biodiversity? Part 2
1991	SPRING (March)	Park Plan 90 and Ministry of Forests Wilderness Areas Plan Old Growth Forest Strategy Report Endangered Somas Delta Undeveloped Watersheds on Vancouver Island Squamish Eagles and Baynes Island ER

SUMMER 1991

Biological Diversity: What’s it all about?

(This is the second part of an article published in the Spring 1990 issue of Bioline, the official publication of the Association of Professional Biologists of BC. The first part, which ran in the November 1990 issue of The Log, outlined seven reasons for conserving biological diversity. Edited for space. Ed.)

Diversity and Stability

The notion that greater species diversity in ecosystems is associated with greater community stability was among the most influential beliefs in ecology from the 1960s to the mid-1970s, sometimes reaching the status of a home truth or ‘core principle’. Then, some theoreticians, like Robert May, began questioning the relationship, pointing out that, as a mathematical generality, increased complexity should decrease community stability, and that it is not true that in the natural world population stability is uniformly associated with floral and faunal diversity and trophic complexity. Even May, however, allowed that natural ecosystems are the product of a long history of coevolution, and intricate evolutionary processes could have produced mathematically atypical systems with long-term stability. Chaos theory now tells us that these systems could be typical in new mathematics—but that’s another story.

Evidence from, for example, below-ground food webs in an American grassland now suggest that the compartmentalization, reduced connectance and interaction strength associated with greater diversity can stabilize food webs. The number of energy ‘channels’ increase with diversity, so compartmentalization increases as communities become more complex, and food-web connectance and average interaction strength decline. Population stability can exist in complex food webs.

What Needs to be Done?

Biological diversity is disappearing most rapidly outside North America, particularly in the tropical rainforests. Prominent biologists are calling for an immediate effort to chart the biodiversity of Earth—a ‘quick and dirty’ survey. There is no time for exhaustive studies, for science as usual. Projects should take two or three years to complete. The plan is not to do detailed inventories and taxonomic surveys, but rather to identify areas rich in biodiversity so that something can be done before they disappear.

Biological impoverishment is also a serious problem in British Columbia. We too need some quick biotic surveys—the sort of work that should have been done decades ago but for a variety of reasons wasn’t. We need a provincially0 or nationally-coordinated effort to collect, synthesise, and disseminate such information. The idea would be to select a few taxonomic groups, communities and geographic areas. We could try, for example, freshwater fish, ground beetles, butterflies, vascular plants, birds, amphibians and mammals. In British Columbia we already know which communities and which areas to concentrate on. And we already know enough about some species, communities and areas—the Vancouver Island marmot, the Garry oak savannah, the Osoyoos semiarid biotic area—to do something for them immediately.

We need to move beyond the traditional conseration strategies of establishing habitat reserves and preserving endangered species. Some species have already disappeared and some clearly are doomed, and we will never have reserves in sufficient number and of sufficient size to ‘save’ biodiversity. In such areas of the province as the Lower Mainland and southeastern Vancouver island it is probably too late for some species and ecosystems.

We need land-use planning for biodiversity, and management not just o the wilderness but also of the ‘semi-natural’ matrix where many species now largely reside, used by humans for forestry, grazing livestock, mining and dispersed settlement. Management for biodiversity is not simply some form of ‘special purpose’ management in specific locations or circumstances.

We need to broaden our vision. The real challenge is to think and manage in broad terms as well as in detail, to address the biodiversity of large areas. Of course, expanded horizons could throw up uncomfortably heterodox ideas, as for example”

· Lots of ‘edge’ isn’t necessarily good

· Progressive clearcutting sometimes makes better ecological sense than patchwork logging

· Such disturbances as fire, logging and agricultural clearing can help maintain, even augment, landscape diversity and biodiversity.

“Biological diversity is a new term and an enlarged focus for things we have long cared about,” Hal Salwasser writes. We need to understand the natural world first because we are scientists, second in order to manage the biosphere sustainably, and third to develop strategies for preserving some species and habitats while exploiting others in ways that maintain the original levels of overall diversity—at least to allow some fraction of the original biota to persist. Nothing we can do as biologists is more important.

Jim Pojar, Ph.D, M.Bio

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SPRING 1991

Undeveloped Watersheds on Vancouver Island

For several months, forestry consultant Keith Moore has been working on an inventory of the watersheds of the temperate rainforests of coastal BC. He has developed a classification system for identifying whether watersheds are developed or undeveloped and has classified all the coastal watershed larger than 5,000 ha that flow into saltwater. These are called primary watersheds. This inventory will soon be published by Earthlife Canada as part of the Endangered Species program.

On Vancouver Island, Keith has identified eight primary watersheds larger than 5,000 ha that are undeveloped. This group has been further subdivided into watersheds that are pristine—meaning there has been no past or present logging, mining or road construction—and those that have been slightly modified by past or present development-meaning that less than 2% of the total watershed area has been affected. Using this classification system, the Moyeha, Megin, Sydney, Nasparti and East Ck watersheds, all on the wet coast of the Island are “pristine”, and the Power and Klaskish on the west coast and the Shushartie on the northeast coast are “modified”.

In January of 1991, the Friends of Ecological Reserves issued a contract to Keith Moore to gather available inventory information about these eight watersheds. In addition we asked him to compile information about the Tahsish. This work involves assembling biophysical inventory information on wildlife and birds, fisheries, vegetation and ecosystems, and estuaries in each watershed; collecting land status information; identifying present and proposed protected areas. He will also provide us with information about the past, present and proposed logging, road construction and other industrial activities in each watershed.

Keith has been collecting this information from a variety of government and private sources and from various reports. We expect a completed report from him by the end of February 1991. He reports that there is considerable interest in the issue of unlogged watersheds and strong support for this type of program to assemble the information to provide good profiles of each watershed. However, information on the environmental values in the presently unlogged watersheds is very incomplete and in some cases, completely lacking. There is a great need for much better information before any decisions about future land use in these watersheds are made.

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