| Title: Great Bay Estuary Eelgrass, 2021 | |
| Time Period of Content: June 2021 - October, 2021 | Publication Date: August 2, 2022 |
| Originator: Michael Routhier, UNH, Geospatial Science Center | |
| Abstract: The dataset shows the locations where eelgrass was observed during the 2021 field season within the following waterbodies: Great Bay, the mouth of the Squamscott River, the tidal portion of the Lamprey River, the tidal portion of the Oyster River, the tidal portion of the Bellamy River, the Piscataqua River and Portsmouth Harbor and its associated creeks, and the coastal shore of Odiorne Point. Photointerpretation was completed on orthophotography collected using a UAV within Great Bay and Little Bay. Aerial orthophotography from the State of Maine was utilized to allow for photointerpretation of the Piscataqua River region, Portsmouth Harbor, Little Harbor, Newcastle, and Oriorne Point areas. Sentinel satellite imagery was also used to further complement these datasets to help within photointerpretation. Vertical UAV imagery was collected as five spectral bands inclusive of RGB, Red-Edge, and Near Infrared bands. Imagery was collected with varying 1.7 to 3.4 cm spatial resolutions based on 100 to 400 ft flight altitudes specific to FAA maximum flight restrictions around the Pease International Tradeport. Areal Vertical aerial photography was collected as for spectral bands inclusive of RGB and Near Infrared, with a nominal 1 foot spatial resolution. The Sentinel satellite imagery was acquired for the date of June 28th, 2021 with a nominal 10 meter spatial resolution. Environmental conditions included a low-sun angle, low tides, low cloud cover, calm winds, no preceding rain events, and low turbidity in the water column were maintained throughout the course of the survey. The eelgrass habitat mapped from the aerial imagery was verified using the ground truthing data from preselected locations and ad hoc locations chosen during the course of the field work. Ground truthing was done from a small boat during the same season as the photographs were taken. Ground truth observations were made on all tides using a drop camera with video recording capabilities and at low tide when visual observations were recorded. Positions were determined using high accuracy Trimble GeoXT GPS unit. | |
| Theme Keywords: biota, Eelgrass, Estuary, Estuarine | |
| Full Metadata and Data Download | |