On November 3rd, we discussed the future of Wright's Branch, a headwater stream that has experienced significant problems due to unrestricted cattle access to the stream, westlands, and springs. The uppermost portion of the stream is deforested to allow for cattle grazing, whereas the lowermost portion is completed forested. From looking at pictures (availabe on the Scholar site), it is evident that the stream has unstable banks, is very turbid, and has a very small average sediment size. Trout Unlimited recently accepted an Embrace a Stream Grant for the deforested section of Wright's Branch, but construction has yet to begin. Thus, the focus of this discussion was to evaluate the current conditions of Wright's Branch, dsicuss future activities, and to evaluate the goals and objectives of the grant.
-Current conditions
- What we know
-Headwater stream that flows into the Roanoke River
- Located on private land and thus recieves no fishing pressure
- Anecdotal evidence of historical brook trout populations
- Cows have unrestricted access to the stream, westlands, and springs
- High turbidity
- Bank instability/erosion
- No riparian vegetation
- High percentage of fine substrate
-What we need to know
- Current channel geometry
- Hydrographic regime
- Daily and seasonal changes in stream temperature
- Water quality
- Which springs contribute the most to normal base flows
- Amount of current and potential brook trout habitat
- Stream carrying capacity
- Food availability
- How compliant the landowner is willing to be
-Evaluation of the Embrace a Stream Grant
- Grant goals include the introduction of brook trout, restoration of the riparian zone, and resotration of the watershed
- Is brook trout restoration feasible?
- Evidence of some brown and rainbow trout populations downstream
- Doubts that sediment size will increase fast enough to support natural reproduction in a short temporal scale
- Stocking source is Trout in the Classroom (TC), but they usually use brown or rainbow trout. It has not yet been determined how viable TC brook trout will be.
- Literature indicates that hatchery brook trout may not successfully spawn in natural conditions, at least not for several years.
- Can the riparian zone and watershed be restored?
- Unlikely that the land owner will support complete fencing of of cattle from all springs and wetlands
- Doubts that the riparian plantings will be successfull
- May require longterm maintenance, but there is no provided monetary of physical support in the grant.
- If cattle are not completly restricted from wetlands and springs, it is possible that poor instream water quality due to high nutrieds will persist. The idea of a 50-ft buffer was introduced as it has been shown to reduce nutrient loads in other streams.
- Are the goals of the grant appropraite?
- One major goal of the grant is to establish naturally reproducing brook trout populations. All indications are that that goal will not be realized.
- Calls for stocking trout 6 months after beginning restoration. It is unlikely that the current stream conditions will have changed enough to support trout populations and rushing to stock trout will likely cause failure.
- Because the stream is not fished, it could be used for introduction of nongame endangered species of natural recolonization. However, because TU is funding it, it's primary motivation has to be around trout restoration. It is likley another funding source could have been found to promote restoration for other species.
- Longterm outlook
- Grant calls for monitoring for three years. That length of time seems to short, especially to determine if the trout poplations are naturally reproducing. There should be a much longer monitoring effort and plans to report results in an efort to aid in future stream resotration activities.
- At the conclusion of monitoring, it is likley that the project will be considered a failure because appropriate goals were not set from the beginning.
- Overal Conclusions Determined by the Class
- The stream is currently unstable due to unrestricted cattle access
- There are numerous uncertainties about the current stream condition that should be assessed before continuing with restoration.
- The Embrace a Stream Grant calls for restoration of brook trout, but the goal seems unattainable given the short time frame and complexity of the situation.
- It is likely that this restoration project will be considered a failure even if it does result in a more stable stream channel and overall better water quality.
- Better pre-project goal assessment would hav increased the likelihood of success
