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Notes on Species/Habitat Outlines
RATIONALE
The species/habitat outlines are intended to provide the scientific background for making
ecologically sound habitat assessments specific to the British Columbia coast. One
criticism of most habitat assessments or evaluations carried out as part of the standard
development project review is that they tend to be only concerned with one species or
group of organisms (e.g. Pacific salmon). This approach simplifies the logistical
problems of conducting rapid assessments, but falls far short of generating an ecological
evaluation from which habitat managers can make decisions about project approval,
mitigation and compensation. The species/habitat outlines provide succinct summaries of
marine and estuarine nearshore habitat utilization and other pertinent information for 49
of the most economically and ecologically "important" organisms that support
commercial, recreational and Native fisheries. They have been developed to provide field
personnel with a species specific, ecological summary. Hopefully, they will impress upon
users that coastal habitats support a diverse and dynamic flora and fauna, and that
assessments must consider entire life cycles and include sufficient temporal and
geographic boundaries. The outlines also provide a foundation for developing the habitat
description and assessment procedures manuals.
SPECIES / HABITAT DOCUMENTATION
The species/habitat outlines consist of two main components: succinct text summarizing
existing scientific information and figures showing habitat utilized and generalized life
cycles. The format was developed to provide manual users with a short, easy-to-use guide
to assist habitat assessment. Each species/habitat outline includes information on the
following:
- taxonomy
- ecological data
- growth rate
- fishery
- references
- generalized life cycle, habitat utilization, and coastal distribution
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The main categories are discussed below. TAXONOMY
A basic taxonomic summary is provided to assist manual users determine to which group a
particular organism belongs, since popularized Family names are often used in the
literature to describe groups of animals. It also shows how the organisms are grouped
according to similar characteristics, and will assist users to obtain more detailed
information in text books or other more complete references. ECOLOGICAL DATA
Although the primary focus of the manual is on habitat, it is important that an ecological
approach be used in habitat assessments. To encourage use of a more ecological approach,
notes are included on habitat and trophic interactions, including: (a) Distribution
Many species have a wide distribution and are relatively abundant. Others may have a
much more limited distribution either latitudinally or geographically, or according to
exposure or other factor.
(b) Habitat
Information under this heading will probably be the most critical for habitat
assessments. The habitat zone addressed in the manual is the coastal area between the
riparian and 20 m subtidal depth. Habitat utilization was summarized according to the
dominant stages of the life cycle. It attempts to stress the temporal nature of habitat
utilization. For example, a continuum of habitats are used during the life of an organism
and habitat assessments should try to determine how the development will affect the
functional relationship between organism and habitat.
(c) Tidal elevation
Habitat utilization during much of a species life cycle is often largely confined to a
restricted tidal zone. Therefore, it is important that habitat assessors be aware of
specific usage. In other cases, habitat utilization varies with each stage in the life
cycle.
(c) Food and predators
Primary food sources or prey are identified to try to show some of the ecological
relationships for each of the 49 species.
GROWTH RATE
An indication of growth rate helps to provide some insight into habitat utilization. For
example, slow growing organisms may reside in a particular habitat for extended periods of
time, or the size of an animal may affect the amount of habitat required per individual,
or size can be a useful characteristic for species identification. FISHERY
Some species are more important economically and may require more restrictive habitat
protection. Under this heading the size and/or value of the recent fishery may be
provided, based on 1986 commercial catch statistics, or noted as being important. Quotas
or fishing limits may also be useful information and was included where available. REFERENCES
The most "useful" references were included to guide manual users to more
complete scientific literature describing habitat utilization. More extensive references
are provided in the Appendix report. As new data becomes available our understanding of
habitat utilization will improve, and the existing references updated easily. FIGURES
A three part figure was included for each species which shows (a) habitat utilization, (b)
coastal distribution and (c) life cycle. Species illustrations are also included at the
end of the report. Part A Habitat Utilization
Habitat utilization shows a cross-sectional view through typical habitat, from riparian
to 20 m depth. It attempts to guide the manual user by indicating intertidal and subtidal
utilization, dominant vegetation types, substrate, etc.
Part B Coastal Distribution
Coastal distribution presents a hypothetical reach of inshore and open coast, along
with the dominant habitat types. The area where one would expect to find the organism is
shown by the shading, "expected presence". This figure will assist the manual
user in considering the importance of habitats to specific organisms.
Part C Life Cycle
Life cycle provides a simplified schematic identifying the main life stages. For some
species the life cycle could be well represented by a figure, while others were more
complicated and text seemed more appropriate. The aim of the life cycle figure was to
provide the manual user with a more ecological impression of habitat utilization.
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