In search of the Lower Fraser’s lost streams

I became interested in quantifying the lost streams in the Lower Fraser in my pursuit to understand what fraction of the historical salmon habitat of the area remains accessible today.

By combining an estimate for the locations and extents of lost streams with information on barriers to fish passage in Lower Fraser Streams we can estimate the proportion of historical salmon habitat that remains accessible. The inclusion of lost streams in this estimate is important in informing our understanding of remaining habitat as it guards against shifting baselines and can help inform targets for restoration.

The rest of my research will focus on quantifying the benefits of removing fish barriers and assessing the quality of what freshwater habitats that remain. By explicitly considering the costs and benefits of restoring access past each known barrier we can map a way forward towards restoring these historically productive ecosystems in a way that is economically efficient and ecologically valuable.

By combining the historical perspective with modern systematic planning ideas, my research helps to illustrate what once was, and will support the efforts of Raincoast and others to protect and restore freshwater habitats throughout the Lower Fraser into the future.

Riley Finn