A derivative of DFO's benthic imagery surveys for the Marine Conservation Targets Program in the St. Anns Bank Marine Protected Area (https://open.canada.ca/data/en/dataset/2a55e2b4-cbb6-4fea-b17e-a16f5e99e68f), occurrence records in this analysis represent presence/absence and density of a biogenic habitat-forming species in five drift-camera transects in the southeast corner of the MPA, off the coast of Cape Breton, Nova Scotia, Canada. Presence/absence and count data of the unstalked crinoid (Heliometra glacialis) were derived from the use of high-resolution Nikon D850 still images (n=428, see link to parent record for more descriptive survey information and complete imagery dataset) and continuous high-definition video observations (approximately one observation every second using a 1Cam Mk6, SubC Imaging camera; n=8522). Densities were estimated by dividing the crinoid counts by the field of view (calculated from lasers with 10-cm spacing). Substrates were reported for each video observation, documenting the dominant substrate (>50% cover) according to a modified Wentworth scale (i.e., sand, gravel, pebble, cobble, boulder, bedrock; Wentworth 1922). Crinoids were observed in ~44% of the area of the five transects (~4811 m2), forming dense beds along sloped features from 77-119-m depths, predominantly on cobble and pebble substrates, reaching densities of up to 59 ind. m-2 and 139 ind. m-2 in the digital still images and video observations, respectively.Cite this data as: Lawton P, Teed L. Fine-scale observations of high density Heliometra glacialis (Crinoidea) beds from five near-seafloor imagery transects from a two-year survey in the St. Anns Bank Marine Protected Area, Atlantic Canada. Published March 2026. Coastal Ecosystems Science Division, Fisheries and Oceans Canada, St. Andrews, N.B.References:- Wentworth, C.K. 1922. A scale of grade and class terms for clastic sediments. The Journal of Geology 30(5): 377-392.

**ATTENTION! The files in this dataset are designed for streaming, not downloading. For the best experience, please follow the instructions available in the resources.**In replacement of the former Canadian Digital Elevation Model (CDEM) that is no longer supported, the Medium Resolution Digital Elevation Model (MRDEM) product is a multi-source product that integrates elevation data from the Copernicus DEM** acquired during the TanDEM-X Mission (AIRBUS, 2022), and the High Resolution Digital Elevation Model data derived from airborne lidar. This product provides a complete, 30 meters resolution, nationwide coverage for Canada. It includes a Digital Terrain Model (DTM), a Digital Surface Model (DSM) and other derived products. The spatial coverage extends into the USA, where needed, to provide coverage for cross-border watersheds in support of hydrological studies and applications. The MRDEM-30-DSM is partially based on the GLO-30 version of the Copernicus DEM** (hereafter named GLO-30). Since elevation values from the GLO-30 are referenced to the EGM2008 geoid model, they were transformed to the Canadian Height Reference System of 2013 (CGVD2013), using the CGG2013 geoid model. Where available, the MRDEM-30-DSM integrates surface data from the lidar-derived HRDEM mosaic, resampled from 1 m to 30 m. The process to generate the MRDEM-30-DTM is more complex. Where available, the HRDEM Mosaic derived from lidar was used since it already provides reliable terrain elevation values. The HRDEM Mosaic data used was resampled from 1m to 30m. Elsewhere, the processing workflow combines a forest removal model and a settlement removal model that is applied to the GLO-30 values in order to estimate the terrain elevation values. Both datasets are projected to Canada Atlas Lambert NAD83 (CSRS) (EPSG:3979).The MRDEM is referenced to the CGVD2013 which is the reference standard for orthometric heights across Canada.The product Medium Resolution Digital Elevation Model (MRDEM) is part of the CanElevation Series created in support to the National Elevation Data Strategy implemented by NRCan.** This product was in part produced using Copernicus WorldDEM-30 © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014- 2018 provided under COPERNICUS by the European Union and ESA; all rights reserved.The organisations in charge of the Copernicus program by law or by delegation do not incur any liability for any use of the Copernicus WorldDEM-30.

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**

The Sentinel mirror is maintained by the Government of Canada through the Copernicus collaborative ground segment program as well as EUMETSAT. Data is made available as quickly as possible based on Canada coverage availability at the source. **This third party metadata element follows the Spatio Temporal Asset Catalog (STAC) specification.**