Quantifying Intertidal Habitat Relative Coverage in a Florida Estuary Using UAS Imagery and GEOBIA

Abstract

Intertidal habitats like oyster reefs and salt marshes provide vital ecosystem services including shoreline erosion control, habitat provision, and water filtration. However, these systems face significant global change as a result of a combination of anthropogenic stressors like coastal development and environmental stressors such as sea-level rise and disease. Traditional intertidal habitat monitoring techniques are cost and time-intensive, thus limiting how frequently resources are mapped in a way that is often insufficient to make informed management decisions. Unoccupied aircraft systems (UASs) have demonstrated the potential to mitigate these costs as they provide a platform to rapidly, safely, and inexpensively collect data in coastal areas. In this study, a UAS was used to survey intertidal habitats along the Gulf of Mexico coastline in Florida, USA. The structure from motion photogrammetry techniques were used to generate an orthomosaic and a digital surface model from the UAS imagery. These products were used in a geographic object-based image analysis (GEOBIA) workflow to classify mudflat, salt marsh, and oyster reef habitats. GEOBIA allows for a more informed classification than traditional techniques by providing textural and geometric context to habitat covers. We developed a ruleset to allow for a repeatable workflow, further decreasing the temporal cost of monitoring. The classification produced an overall accuracy of 79% in classifying habitats in a coastal environment with little spectral and textural separability, indicating that GEOBIA can differentiate intertidal habitats. This method allows for effective monitoring that can inform management and restoration efforts.

Editorial for Special Issue “Remote Sensing for Monitoring Wildlife and Habitat in a Changing World”

“…The works included in this Special Issue present some scientific and technological innovations in remote sensing for assessing the spatio-temporal dynamics of wildlife species and their habitats. Although constituting a very small set of studies, they cover a diverse array of geographic settings distributed throughout the world and comprising both terrestrial [6][7][8][9][10][11][12][13][14] and aquatic [9,12,15,16] systems (Figure 1). They also evaluate individual species groups, including corals [15], reptiles [6,9], birds [7,10], mammals [8,11,13,14], or a combination of different species groups [12,16].…”

“…Although constituting a very small set of studies, they cover a diverse array of geographic settings distributed throughout the world and comprising both terrestrial [6][7][8][9][10][11][12][13][14] and aquatic [9,12,15,16] systems (Figure 1). They also evaluate individual species groups, including corals [15], reptiles [6,9], birds [7,10], mammals [8,11,13,14], or a combination of different species groups [12,16]. These studies used diverse analytical Remote Sens.…”

“…terrestrial [6][7][8][9][10][11][12][13][14] and aquatic [9,12,15,16] systems (Figure 1). They also evaluate individual species groups, including corals [15], reptiles [6,9], birds [7,10], mammals [8,11,13,14], or a combination of different species groups [12,16].…”

“…terrestrial [6][7][8][9][10][11][12][13][14] and aquatic [9,12,15,16] systems (Figure 1). They also evaluate individual species groups, including corals [15], reptiles [6,9], birds [7,10], mammals [8,11,13,14], or a combination of different species groups [12,16]. These studies used diverse analytical approaches applied to remotely sensed data acquired by different sensor systems at different scales ranging from high spatial resolution sensors onboard unoccupied aircraft vehicles [16], underwater systems [15], and space-borne vehicles [12], to intermediate spatial resolution multispectral imagery acquired by operational satellite sensor systems such as the Landsat [6][7][8]10,11,14], SPOT [7], and MODIS [8,13] satellite series, together with coarser spatial resolution data acquired by weather satellite systems [9].…”

“…They also evaluate individual species groups, including corals [15], reptiles [6,9], birds [7,10], mammals [8,11,13,14], or a combination of different species groups [12,16]. These studies used diverse analytical approaches applied to remotely sensed data acquired by different sensor systems at different scales ranging from high spatial resolution sensors onboard unoccupied aircraft vehicles [16], underwater systems [15], and space-borne vehicles [12], to intermediate spatial resolution multispectral imagery acquired by operational satellite sensor systems such as the Landsat [6][7][8]10,11,14], SPOT [7], and MODIS [8,13] satellite series, together with coarser spatial resolution data acquired by weather satellite systems [9]. This diverse array of sensors and analytical approaches proved useful for evaluating habitat requirements and distribution [7,8,10,12,16], species distribution and occurrence [11,15], population dynamics [7], human-wildlife conflicts [13,14], the negative impacts of natural [9] and human-driven [8] disturbances on species distribution, and for assessing the potential impacts of climate change [6].…”