The TIDES approach uses a relatively low-cost and easily transferrable methodology designed to engage communities directly in the research and management of their coastal areas. Using a simple pulley system, we capture thousands of aerial images over around 180 square meters of rocky intertidal habitat. These high-resolution photos are then stitched together by a commercially available structure-from-motion software (Agisoft Metashape) to create very detailed 3D habitat maps of these highly complex ecosystems.
We repeat these large-area imaging surveys on a seasonal basis to determine short-term and seasonal changes within the biological composition of the habitat. We keep track of which organisms make up what percent of the available habitat in our study areas, and how this changes over time.
Because rocky intertidal organisms exist within strict ecological zones, we can track how these zones shift over time and how these biological changes are associated with local changes in sea level.
Sea level rise is a long-term trend, but the actual sea level at a specific location changes very frequently with the tides (that’s how we got our project name!), wave height and force, storms and winds that force more or less water up toward the shore, etc. etc. etc. So many factors influence sea level at any given moment.
Luckily for us, scientist have been able to determine specific sea level by region using a combination of tide gauges and buoys, and specific calculations. The TIDES team uses this information from systems like the Southern California Coastal Ocean Observing System (SCCOOS) alongside the biological data we gather in our surveys and extract using Viscore to determine how these short-term changes in sea level influences the community composition and patterns of zonation in the rocky intertidal.
In this way we can better understand the vulnerability of these ecosystems to both short term changes in sea level, and the long-term trend of sea level rise in order to better support climate change management plans for our iconic coastal seascapes.