I am working towards a MS in Marine Resource Management in the College of Oceanic & Atmospheric Sciences at Oregon State University.
The Confederated Tribes of the Siletz Indians' (CTSI) Pacific lamprey project, funded by the USDA Forest Service - Rural Community Assistance Program, investigates factors of the Pacific lamprey (Lampetra tridentata) decline in the Rock Creek drainage of the Siletz River basin. The Pacific lamprey was a primary food source for the Pacific Northwest Indians, including the Siletz tribe. In recent years, the Pacific lamprey appears to be suffering a population decline in the Siletz River basin. Throughout the study, the following issues will be addressed: causal factors of the population decline, healthy ecosystem requirements for the lamprey, design of sustainable ecosystem management strategies, and cultural and environmental education for tribal members. This project is unique because it integrates native knowledge with scientific research and modern day technology to understand the plight of the lamprey and to make sound resource management decisions.
The Pacific lamprey is an important part of the Siletz Indian native lifestyle. The most predominate role of the lamprey is its use as a food source. The lamprey is a high-energy food; packed with vitamins and minerals that has four times the caloric value per weight of salmon. Additionally, native American tribes use the lamprey and its components for medicinal and ceremonial purposes. The Pacific lamprey, just as any other native animal species, plays an important part of the ecosystem ecology. If the lamprey populations are declining then this could be an indicator of greater ecological problems in the native area of the region.
One of the important parts of the GIS is the data involved. Because the Siletz Indians knew they would be collaborating with the watershed council and other government agencies, we decided that it would be important to have data collected using established standards. The Oregon Department of Fish and Wildlife (ODFW) Aquatic Inventory Project is an established protocol for collecting stream survey data and it provides quantitative information on aquatic and riparian habitat condition throughout Oregon.
Pacific lamprey, an anandromous species, begins life as filter feeders in freshwater rivers, continues to live as a parasitic adult in marine waters and returns to their native rivers to spawn. This complex life cycle is particularly sensitive to changes in the environment. Information on the lamprey life requirements is an important component of models that would show which areas of the river are livable. It is necessary to understand the ecological and biological requirements of the Pacific lamprey, if a habitat analysis is going to be done. I compiled a summary of all the biological and ecological data I could find on the Pacific lamprey. Since most of the research on Pacific lamprey has been in Canada, the Siletz Indians will need to take care when interpreting the data for their models.
The ODFW stream survey data is collected on the river unit scale. These units can be less that 10 feet to over 100 feet long. This creates a unique problem when trying to attach stream survey data to an arc river network coverage. Typically, there would be one arc for each river unit and its associated habitat data. However, this becomes problematic if you have data that is not partitioned along river units. Little Rock Creek had over 700 river units in approximately 5 river miles and the resulting ARC/INFO file would be very large. Additionally, it is not possible to accurately digitize the small arcs needed for short segments. Since the main criteria for establishing this GIS is to be able to actively use the information for management decisions, it was necessary to find a more efficient and flexible means to link the aquatic habitat data. Dynamic segmentation is an ARC/INFO network analysis tool created by ESRI, which presents solutions to the difficulties encountered by traditional methods. Dynamic segmentation allows the user to link data to arcs, regardless of the arc length. This means the coverage does not have to be digitized using the river units and the arcs can be any lengths necessary. The ARC/INFO file will be a more manageable size using fewer arcs, instead of using individual arcs for each river unit. Since arc length is not the controlling factor for attaching data, it is not necessary to have data partitioned by river units. This allows for other forms of data to be associated with the same stream coverage. Dynamic segmentation can also be used as a powerful tool for queries. It allows the user to find where habitat meets criteria along the stream continuum, as well as what habitat is available at a specific point.
Dynamic segmentation makes measurements along the route you create. For Rock Creek, I made each creek, one arc and one sub-route. The entire basin belongs to one route, so that other creeks can be added easily in the future.
In order to get the data connected to the sub-route in the correct place it is necessary to calibrate the arcs. For example, I use a stream coverage from the Oregon GIS Center for my stream arcs. Then I created a coverage of known points (known on the survey data and known on the ground) to tell ARC/INFO how long each segment should be. Once this is completed, you can use ROUTESTATS to find out the error.
By creating EVENTS, I was able to link the stream survey data to the measured sub-routes I had created.
This image shows the output of a simple boolean query on Little Rock Creek. The blue lines are other creeks in the basin and the brown lines are roads. The red sections of Little Rock Creek did not meet the query criteria.
This is a close up of the square region shown in the previous image. The yellow region shows the area that did meet the query criteria.
