Biodiversity Management

Ecosystem Management

Conservation biology is interdisciplinary, requiring input from science, medicine, geography, law, economics and other disciplines. Our current knowledge and ability to manage natural biodiversity is limited.

Maintaining habitat is fundamental to conserving species and genetic diversity. Populations that fluctuate widely are more likely to go extinct than populations that are more stable.

Management of ecosystems requires the use of adaptive management that continuously improves our understanding of what needs to done and how we can progressively deliver more effective planning techniques.

Goals

On December 18, 2022, the United Nations, set an international target of ensuring that by 2030 at least 30 per cent of terrestrial, inland water, and of coastal and marine areas, especially areas of particular importance for biodiversity and ecosystem functions and services, are effectively conserved and managed. Canada and British Columbia adopted these targets. (Decision adopted by the conference of the parties to the convention on Biological Diversity, COP15)

Governments have not yet decided how to implement the 30% goal. One method would be to identify and set aside 30% and protect it as a biodiversity reserve. The current method of protection could be described as aspirational and mainly consists of setting guidelines. The method needs to be evaluated to determine if it is effective. A precautionary approach is appropriate.

Adaptive Management

(see also Ecological Management)

Ecological management reflects many different interests and choices. Management of ecosystems requires:

• set objectives and targets for biodiversity in plans
• coordination at multiple levels of biological organization, for multiple time and spatial scales. This requires management of landscapes using the coarse filter approach, combined with management at the species level.
  1. The ‘coarse filter’ approach refers to the management of landscapes through a network of protected areas, and their buffer zones, that attempts to emulate and conserve natural ecological processes within the natural range of variability.
  2. ‘Fine filter’ studies approach the management of biodiversity at the species level through an individual or localized perspective when species issues are not effectively addressed by the coarse filter approach. Individual species sometimes require special attention, sometimes in localized areas.
• management of all native species towards viable populations
• an awareness of what is happening to the ecosystem and species within the ecosystem
• minimizing disruption of habitat in protected areas

Evaluation

Management requires performance evaluation. Objectives, indicators and targets for biodiversity should be documented in management plans to integrate with resource use activities. Measurable indicators need to be developed to monitor whether management objectives are being attained. Measurable indicators provide needed ‘red flags’ in situations requiring corrective action.

Management Principles

Ecosystem-based management (EBM) can be defined as an adaptive approach to managing human activities, seeking to ensure the coexistence of healthy, fully functioning ecosystems and human communities. Adaptive management is a systematic/scientific learning process that formally plans and monitors the outcomes of decisions to improve our ability to better manage natural resources, given uncertainty and risk.

Some of the key characteristics of active adaptive management include:

• Management is treated as experimental, testing innovative approaches.
• A number of policies or practices are selected for implementation.
• There is recognition of a large amount of uncertainty in processes and events.
• Alternate models or sets of explanations are developed.
• Key management and other actions are defined at the necessary scale.
• Scientists, stakeholders, politicians and citizens are involved in the learning process.

Strategies for improving decision-making with incomplete knowledge include:

• ‘trial and error’, in which initial choices are a ‘best guess’ with later choices chosen from a subset that gives better results
• ‘passive adaptive’ where one model is assumed to be correct
• ‘active adaptive’ where multiple alternate models are linked to policy choices

Where there is insufficient data or more uncertainty, a conservative approach is needed.

Principles for the Selection & Design of Protected Space : Landscape

Appropriate management practices can help ensure the persistence of landscape elements, critical habitats and features and prevent loss of native species. Some areas support a wide variety of species, others support rare species, and still others support relatively few yet common species.

Size : Retain Large Contiguous or Connected Areas

To sustain genetic and functional diversity, a broad geographic distribution of ecosystems and species must be maintained within forest and range lands.

B.C. still has areas of ‘wild’ ecosystems where natural or near-natural ecological processes such as predator-prey dynamics remain intact. The areas left continue to shrink each year. Large contiguous and connected areas support natural ecosystems and provide critical habitat for a wide variety of species. Large areas of habitat usually contain a larger variety of species than smaller areas of similar habitat. Species well-distributed across their native range are less susceptible to decline.

Providing a distribution of habitats is important to sustain native species

Representative Samples in Key Areas

Areas selected must effectively support representative species.

Examples of all ecological zones need to be protected. Select areas representing the range of natural ecosystem types.

‘Critical habitats’ are geographic areas that are essential to conserve species of concern or maintain workable populations.

‘Critical features’ are components of habitat needed to help conserve species of concern and maintain viable populations.

Preserve rare landscape elements, critical habitats and features, and associated species such as clean gravel for spawning, wildlife trees used by cavity nesters, and caves used by bats.

Connectivity-Corridors/Fragmentation

Connectivity and fragmentation are both important contributors to ecosystem function and processes.

Fragmentation is the degree to which organisms are split into distant resource patches that can’t cross fertilize and support each other. When habitat is fragmented by highways, urban sprawl, clearcut logging, animals get cut off from their migratory paths connectivity is lost adversely affecting biodiversity.

Connectivity of habitat allows individual organisms to move in response to changing conditions, such as seasonal cycles, a forest fire or climate change. What constitutes connectivity is scale-dependent and varies for each species, depending on its habitat requirements, sensitivity to disturbance and vulnerability to human-caused mortality.

The degree and characteristics of natural connectivity vary with differences in landscape types. For example, some habitat types (e.g., caves, bogs, cliffs) may be naturally fragmented, others (e.g., streams, riparian habitat) are essentially linear and others are often distributed in large blocks or patches.

The management challenge is—how to deal with habitats that existed naturally in large patches but which, as a result of human activity, have been converted into much smaller, sometimes isolated patches. To enable large areas to be connected, obstacles such as highways may need to be modified for safe passage of fish and wildlife. Urban development planning that secures riparian conservation zones to maintain fish habitat and wildlife corridors enhance connectivity.

Preservation vs. Restoration

Select available locations never before harvested or utilized for domestic purposes with the resulting modification of biodiversity. Selection of areas with irreversible damage from land use, such as species loss, should be avoided. It is easier to protect areas than attempt to restore them. Parks in the Vancouver area overrun with blackberry, Japanese knotweed and policeman’s hat are near impossible to restore because root fragments have to be identified and removed, a slow process that takes years.

It is generally more expensive to recover a population that is threatened or endangered than it is to avert population collapses caused by crossing threshold levels.

It is best to avoid mitigation as a means to compensate for the effects of human activities on biodiversity. Compensation for impact should require setting aside alternate and equivalent sites.

Anticipate Encroachment

Buffers: smaller protected areas need natural buffer zones as protection from the impact of cities, industry and farms. These should be incorporated at the time an area is protected. Purchasing land for buffer zones and wildlife corridors as encroachment starts to occur can be costly.

The habitat needs of most forest and range organisms can be provided for by:

• maintaining a variety of patch sizes, seral stages and forest stand attributes and structures across a variety of ecosystems and landscapes
• maintaining connectivity of ecosystems in such a manner as to ensure the continued dispersal and movement of forest and range-dwelling organisms across the landscape
• providing forested areas of sufficient size (1) to maintain forest interior habitat conditions and (2) to prevent the formation of excessive edge habitat.
• ensuring that the abundance and distribution of native species is not reduced by human activities

Generally,

• large blocks of habitat containing large populations of a target species are more effective than small blocks.
• habitat in continuous blocks is better than fragmented habitat.
• interconnected blocks of habitat are better than isolated blocks. Disconnected populations of species are more likely to be genetically impoverished.
• blocks of habitat close together are better than blocks far apart.
• blocks of habitat that are roadless or inaccessible to humans are better than accessible habitat.
• ecosystem boundaries should be determined by natural boundaries.

Species Management – Fine Filter Approach

Management of individual species on a population level involves both a focus on threatened species and habitats, as well as a focus on the general population. Management of individual species remains a necessary part of any conservation strategy. Without individual attention many species have declined.

Species must be managed in response to environmental change.

*See also principles adopted in the British Columbia Guidebook