Why environmental inventories are insufficient for conservation planning: Comments on the 2008 PGL report on CRC

by Alejandro Frid,, February 28, 2008


Here I comment on the PGL (January 2008) report on CRC. To make the best use of the time I can allot to volunteer work, I will focus on ecological issues that complement the expertise and input of local naturalists (e.g. S.E. Fast, A Whitehead, B. Gowans and others). In essence, I have guessed what these other folks can address and stayed clear from it.

The PGL report is an inventory that maps and lists ecological attributes at CRC. According to its own introduction, it “is not a detailed environmental impact assessment (EIA) of the CRC project“, and EIAs are expect to follow later. While the inventory is a reasonable first step, the problem is that the PGL report steps beyond the scope of its current analyses by presenting a land use plan that, according to its own conclusion (page 23) will “ensure the protection of the Cape’s functional ecosystem“. That conclusion—which has the potential to influence public opinion and development approval—is currently unsupported due to the following issues.

Main issues

The recommendations and conclusions of the report implicitly assume that understanding biodiversity pattern—the spatial distribution of different species and habitats—is sufficient for long-term conservation planning. This is a fundamental flaw because biodiversity patterns are maintained through ecological processes: interactions between multiple species and habitats that affect the distribution, survival and reproduction of each organism (Pressey et al. 2007). Although the report gives token acknowledgements to some processes (i.e. describes disturbance history and mentions connectivity) for the most part it treats biodiversity patterns as static entities that can be protected by drawing a circle around them and excluding development within that circle. In the short term, that strategy alone might achieve some conservation goals. In the long term, its chances of failing are large because “[b]iodiversity is generated and maintained by processes and, unless we plan for them specifically, many processes will be disrupted or cease altogether” (Pressey et al. 2007:583).

Consider predators, for instance, which indirectly influence the distribution and abundance of plants and other species at lower trophic levels by affecting the mortality rate and foraging behaviour of herbivores and other animals at mid-trophic levels. This general principle applies to myriad taxa, large and small (e.g. Werner & Peacor 2003; Ripple & Beschta 2006, 2007). Even invertebrate predators (e.g. spiders) can indirectly influence plant community composition and ecosystem processes (Schmitz 2008). If reserves are small (as the PGL report proposes) and predators readily cross permeable reserve boundaries, then human activities adjacent to reserves can continue to impact the distribution, reproductive success, and behaviour of predators (e.g. Sergio et al. 2005). What can potentially follow is the severe disruption of predator-driven ecological processes within reserve boundaries (Terborgh et al. 2001; Schmitz 2008). Given that settlers in the early 20th century eliminated wolves, the former top predator, from Bowen Island (Armitage 2001), in present-day CRC these concerns might be most applicable to human influences on the hunting distributions of owls, raptors and mustelids, but the list of expected predators at CRC (including small-bodied and invertebrate predators) would require further examination in this context.

Because ecological processes cannot be studied from scratch in a “land use planning” situation like CRC, general principles available in the refereed literature are essential tools for conservation planning that must be integrated with the known natural history of the area. A recent paper, for instance, provides a synthesis of the concepts and methods for addressing three questions essential to conservation planning (Pressey et al. 2007:583):

  1. Which processes to plan for?;
  2. How to plan for processes?; and
  3. How to choose between processes when conservation resources are insufficient for all to persist?

The PGL report, however, does not address these sorts of question. Thus, its proposed measures for conservation planning deserve little confidence.

This lack of confidence is exacerbated by the report’s second fundamental flaw: the implicit assumption that human threats to biodiversity are static (Pressey et al. 2007). In the face of climate change, this is naïve. There is growing literature on methods and concepts on how to make climate change predictions inherent to long-term conservation planning (Araujo et al. 2004; Hannah et al. 2007; Pressey et al. 2007). Climate change considerations are also inseparable from attempts to conserve natural systems, as recent experimental work demonstrates that multi-species interactions increase ecosystem resilience to climate change (Suttle et al. 2007). To be credible, any follow-up EIAs must rigorously apply these concepts.

Other issues

Here I briefly reiterate some points (not all) from my recent article in the Bowen Island Undercurrent (January 11, 2008. Arguments made there remain unchanged after my reading of the PGL report. The only brand new point here concerns fire management.

Invasive species

It is rather humorous that the PGL report speaks of invasives being present where campers and hikers have disturbed habitats at CRC, which is undoubtedly true, but then ignores how proposed development will exacerbate the invasive species problem to a much larger scale. To be credible, any follow-up EIAs must rigorously apply existing literature on this issue (e.g. Quian & Rickleffs 2006; Pressey et al. 2007).

Biodiversity impacts from dogs

Disturbance from dogs and other pets on birds and other wildlife must be inherent to any protected area management strategy, particularly in the context of the huge number of people that is proposed to be housed at CRC. The impacts from dogs can be severe and extend well beyond the killing of individual wild animals by affecting the habitat use and distribution of entire populations (Frid & Dill 2002; Banks & Bryant 2007). These impacts must be explicitly considered by any follow-up EIAs and park management plans.

Restoration and bioregional representation

The PGL report does not deal with the restoration potential of CRC. My position is quoted below (from the Undercurrent article):

“Although much of CRC was disturbed by old logging, is the ecological restoration potential of the area being considered in a bioregional context? Existing disturbances should not be misconstrued as license for development. CRC, being located near major population centres with a long history of resource exploitation, is surrounded by areas where low-elevation coastal-fringe forests are very fragmented and degraded. Given this bioregional context, the unfragmented forest polygons in CRC that are maturing towards older stages used by habitat-specialist species represent a tremendous opportunity for first restoring and then preserving vanishing habitats.”

Follow-up EIAs and reserve design plans should consider explicitly the restoration potential of CRC. They should also ensure that protected area design at CRC considers bioregional representation at the scale of the Georgia Depression ecoprovince (see Pressey et al. 2007).

Fire management appendix

As someone who spent 14 years in the boreal forest of the Yukon, I am aware of conflicts between fire hazard and rural living. The impacts of “fire smarting” a rural community, however, must be included explicitly in estimates of the net impact of development. The more low density and spread out housing developments are, the greater the unintended environmental impacts of “fire-smarting” will be. Further, under climate change the fire hazard situation could well worsen over time, which will lead to justifications for “fire smarting” and expanding roads into what was originally intended to be protected forest polygons. Follow-up EIAs and land management plans should explicitly consider impacts of “fire-smarting” and related road building in areas that are purported to be protected. Analyses must consider both the climate regime that exists today and that predicted for the future.

Sensitive species

What will the follow-up EIAs actually do? For instance, Townsend’s big ear bat (blue list) and Keen’s longeared myotis (red list) are acknowledged by that report as potentially present but specialised surveys are lacking. Similar issues apply to other species of concern. For instance, will specialised surveys be conducted for marbled murrelet nests?


Based on biodiversity patterns alone, the PGL report proposes spatial restrictions to development. Although that is a reasonable start, the report concludes that “these measures ensure the protection of the Cape’s functional natural systems”. Given the lack of consideration to ecological process and dynamic nature of future threats (e.g. climate change), as well as several lesser but important issues, that conclusion is untenable.

If EIAs are to follow, as PGL’s introduction states, then there is still an opportunity to attempt to address the issues I have outlined. Until then, there is little confidence that PGL’s proposed measures will achieve the longterm conservation of biodiversity at CRC.

As a next move, I strongly recommend that PGL lists, in explicit language, what the long-term conservation objectives are for CRC, and then uses these goals as the guide for all EIAs. If the goal is to address the shortterm conservation of some species and the maintenance of green spaces for recreation, then that should be spelled out and there should be no pretense of long-term biodiversity conservation.

Two principal founders of the discipline of conservation biology, Frankel & Soulé (cited in Pressey et al. 2007: 583), state the “the purpose of nature reserves is to maintain, hopefully for perpetuity, a highly complex set of ecological, genetic, behavioural, evolutionary and physical process and the coevolved, compatible populations which participate in those processes. Hopefully these are the goals that will be pursued at CRC. In which case, PGL and ownership have “miles to go before they sleep”.


Araujo, M., Cabeza, M., Thuiller, W., Hannah, L. and Williams, P. 2004. Would climate change drive species out of reserves? An assessment of existing reserve-selection methods. – Global Change Biology 10: 1618-1626.

Armitage, D. 2001. Around the Sound: A History of Howe Sound-Whistler. – Harbour Publishing.

Banks, P. and Bryant, J. 2007. Four-legged friend or foe? Dog walking displaces native birds from natural areas. – Biology Letters 3.

Frid, A. and Dill, L. M. 2002. Human-caused disturbance stimuli as a form of predation risk. – Conservation Ecology 6.

Hannah, L., Midgley, G., Andelman, S., Araújo, M., Hughes, G., Martinez-Meyer, E., Pearson, P. and Williams, P. 2007. Protected area needs in a changing climate. – Frontiers in Ecology and the Environment 5: 131- 138.

Pressey, R., Cabeza, M., Watts, M., Cowling, R. and Wilson, K. 2007. Conservation planning in a changing world. – Trends in Ecology and Evolution 22: 583-592.

Quian, H. and Rickleffs, R. 2006. The role of exotic species in homogenizing the North American flora. – Ecology Letters 9.

Ripple, W. and Beschta, R. 2006. Linking a cougar decline, trophic cascade, and catastrophic regime shift in Zion National Park. – Biological Conservation 133: 397-408.

Ripple, W. and Beschta, R. 2007. Restoring Yellowstone’s aspen with wolves. – Biological Conservation 138: 514-519.

Schmitz, O. 2008. Effects of predator hunting mode on grassland ecosystem function. – Science 319: 952-954.

Sergio, F., Blas, J., Forero, M., Fernández, N., Donázar, J. and Hiraldo, F. 2005. Preservation of wide-ranging top predators by site-protection: Black and red kites in Do_ana National Park. – Biological Conservation 125: 11-21.

Suttle, K., Thomsen, M. and Power, M. 2007. Species interactions reverse grassland responses to changing climate. – Science 315: 640-642.

Terborgh, J., Lopez, L., Nunez, P., Rao, M., Shahabuddin, G., Orihuela, G., Riveros, M., Ascanio, R., Adler, G., Lambert, T. and Balbas, L. 2001. Ecological meltdown in predator-free forest fragments. – Science 294: 1923-1926.

Werner, E. E. and Peacor, S. D. 2003. A review of trait-mediated indirect interactions in ecological communities. – Ecology 84: 1083-1100.

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