Coastal Cutthroat Trout as Sentinels of Lower Mainland Watershed ...

75To be most effective and efficient, habitat restoration should follow a hierarchicalstrategy based on three elements: (1) protecting existing high quality habitats; (2)restoring natural watershed processes; and (3) applying known effective techniques basedon a watershed assessment (Roni et al. 2002). Thus, the sound approach to restoration isas follows:• initially protect areas of higher quality or key habitats;• then, re-establish access blocked by culverts and reconnect isolated or cut-offhigh quality cutthroat habitats;• next, where feasible restore hydrologic, sediment supply and riparian processes;• then, as needed, restore or supplement nutrients where oligotrophication hasoccurred; and• and finally, restore simplified/lost instream habitats, which are common in urbangeomorphic settings.Coastal cutthroat streams are typically associated with forested areas that werehistorically logged to their stream banks by “practices of the day”. Some riparian forestswere cleared for agricultural expansion and for urban developments. Thus, virtually allRegion 2 cutthroat streams have lost their old growth forests, and at best they have hadonly 60-80 years of forest recovery. At this latitude, this timeframe is insufficient formuch recruitment of large wood to stream channels from existing second growth forests.In fact, the frequency of instream large wood is at its minimum because most of theexisting instream wood has now been lost through losses via decay and transport. Thelatter requires a century to complete its cycle. In the riparian forest cycle, re-supply oflarge wood does not re-initiate until approximately 100 years after riparian logging anddoes reach a maximum until 200 years post-logging. As a clear example of this cycle inthe Lower Mainland, logging-induced losses of in-stream large wood are very evidentwithin the Seymour River. Most coastal cutthroat streams are deficient in large wood asa primary source of pool and cover as key habitat features (Slaney and Martin 1997,Rosenfeld et al. 2000). Until conifers re-dominate the riparian forest, only deciduous (redalder) riparian forests provide minor sources of large wood, which are ephemeral at bestowing to rapid decay. In both urban and agricultural settings this condition isexacerbated by removal of large wood under drainage maintenance programs operated bymunicipalities, which need to be compensated via no-net loss actions.Similarly, lower reaches of many cutthroat stream are channelized and simplified,particularly in urban stream settings. Therefore, remaining LWD and pools are often lost.Small rip-rap is often deployed to re-armour banks of channels that erode withoutinstream LWD, and losses of cutbanks and lateral pools are the end result.Restoration of these degraded habitats is readily feasible and cost-effective, particularlywhere equipment access is available to the channel. Techniques are outlined in Slaneyand Zaldokas (1997) and some of the key techniques are briefly described below as asummary applicable to urban cutthroat streams. Present-day assessments andprescriptions are conducted simultaneously, compared to past separation intoreconnaissance, level 1 assessment, and level 2 prescriptions which were time- and costinefficient.Knowledge of stream restoration for cutthroat has advanced sufficiently to be