Research Questions

What is the frequency and magnitude of landslides that likely blocked salmon migration in the Fraser River?  

We Used LiDAR and surface exposure dating to develop a chronology of past landslides in the Fraser Canyon that impacted salmon migration based on location and magnitude.

How have landslides affected the abundance and diversity of Fraser salmon?

We compared past landslides to the distribution of salmon populations in the Fraser Canyon to assess past landslide impacts on salmon abundance and diversity.

What river morphologies create hydraulic barriers?

We measured channel morphology, flow patterns and velocities, and water level, along the Fraser Canyon to tease apart what conditions create hydraulic barriers to upstream salmon migration.

How do landslides affect environmental conditions that impede salmon migration?

Using radio-telemetry stations and hydraulic information, we examined the fine-scale behavior of radio-tagged salmon past hydraulic barriers and assessed how passage success or failure is determined by river conditions or intrinsic biological characteristics.

How is salmon passage failure, delay, or success determined by river conditions or biological characteristics?

Using radio-telemetry stations and hydraulic information, we will examine the fine-scale behavior of radio-tagged salmon past hydraulic barriers and assess how passage success or failure is determined by river conditions (e.g., discharge, water surface velocity) or intrinsic biological characteristics (e.g., species, population, size).

Is there genetic variation that increases the likelihood of passage success?

Through comparing the genetic signatures of salmon that passed and failed to pass the Big Bar Landslide, we attempted to identify genes associated with the ability to successfully pass hydraulic barriers.

Did the genetics of salmon change following the Big Bar Landslide?

We assessed the impact of the Big Bar Landslide on salmon biodiversity by comparing the genomics of salmon before and after landslide from populations upstream and downstream of the landslide site.

Are there other canyons in the Fraser that are susceptible to future landslides?

Using existing data and on-the-river observations of channel morphologies, we will identified locations that may be susceptible to future events and developed a list f sites of concern: SITES OF CONCERN DOCUMENT AND web map

What is the likelihood of a future landslide damming the Fraser?

We developed a model to predict whether future landslides could be moved by the river and how long they would block the river based on location where the landslide occurred, the size of the landslide material, and the volume of landslide material.

What are the geomorphic and biologic consequences of these events?

We assess how future landslides would affect salmon populations and built a webtool so that the impact can be visualized THE HAKAI WEB MAP: https://arcg.is/1eau010