Satellite remote sensing of submerged kelp beds on the Atlantic coast of Canada

Branching Algorithm to Identify Bottom Habitat in the Optically Complex Coastal Waters of Atlantic Canada Using Sentinel-2 Satellite Imagery

“…While in optically complex temperate environments, Sentinel-2 has been used to map eelgrass beds to depths of 4-5 m (Fethers, 2018;Dierssen et al, 2019), and retrieve bathymetry to 10-m deep in Ireland (Casal et al, 2020), both studies observed that this maximum depth was highly dependent on image quality, and depth limits were significantly shallower under non-optimal conditions, which is consistent with our results. Lastly, while Sentinel-2 has not previously been used to detect submerged kelp beds, SPOT and Landsat have been used to map vegetated bottom habitat (eelgrass and kelps) to depths of 7-8 m in Atlantic Canada (Simms and Dubois, 2001;St-Pierre and Gagnon, 2020) and down to 10 m in turbid waters in Spain (Casal et al, 2011).…”

“…Rockweed habitat can be easily identified using vegetation indices given its strong signal in the near-infrared (NIR) compared to its environment. In the subtidal zone, completely submerged kelp habitat has been quantified with Landsat along the Gaspé Peninsula in Quebec (Simms and Dubois, 2001), with SPOT-7 along the Mingan Archipelago also in Québec (St-Pierre and Gagnon, 2020) and with lidar along the south shore of Nova Scotia (Webster, 2018). Eelgrass habitat has been quantified with lidar (Webster et al, 2016), sonar (Vandermeulen, 2014;Barrell et al, 2015), and a variety of multispectral sensors including Worldview, Quickbird, and SPOT (Milton et al, 2009;Barrell et al, 2015; at various sites along the exposed Atlantic coast of Nova Scotia and along the Northumberland Straight.…”

Combining unmanned aerial vehicles and satellite imagery to quantify areal extent of intertidal brown canopy‐forming macroalgae

“…seagrass, mangroves and coral reef; Chauvaud et al, 1998;Garza-Pérez et al, 2004;Mishra et al, 2006;Mumby et al, 1997). With the exception of canopy algae such as Macrocystis pyrifera and Nereocystis luetkeana, which sit on the surface of the ocean, and shallow subtidal species exposed at low tide or found in areas of good visibility (Anderson et al, 2007;Bell et al, 2020;Casal et al, 2011;Cavanaugh et al, 2021;Finger et al, 2021;Simms & Dubois, 2001;Uhl et al, 2016), few studies have attempted to estimate macroalgal areal extent using remote sensing. For intertidal species, which are bidaily exposed during low tide, remote imagery techniques are a more viable for estimating areal extent (Brodie et al, 2018;Rossiter et al, 2020).…”

A review of sub tidal kelp forests in Ireland: from first descriptions to new habitat monitoring techniques

“…: Mora-soto et al, 2020), satellite data is also useful in mapping kelp species that span the water column, and was pioneered in the east Pacific (M. pyrifera: Mora-soto et al, 2020;Cavanaugh et al, 2010). Simms & Dubois (2010) created a method for submerged kelp beds in the north western Atlantic, which could potentially be used on the subtidal L. hyperborea forests in Ireland.…”