A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> Although satellite imagery is becoming a basic component of the work of ecologists and conservationists, its potential and reliability are still relatively unknown for a large number of ecosystems. Using Landsat 7/ETM+ (Enhanced Thematic Mapper Plus) data, we tested the accuracy of two types of supervised classifications for mapping 13 peatland habitats in southern Quebec, Canada. Before classifying peatland habitats, we applied a mask procedure that revealed 629 peatlands covering a total of 18,103 ha; 26% of them were larger than 20 ha. We applied both a simple maximum likelihood (ML) function and a weighted maximum likelihood (WML) function that took into account the proportion of each habitat class within each peatland when classifying the habitats on the image. By validating 626 Global Positioning System locations within 92 peatlands, we showed that both classification procedures provided an accurate representation of the 13 peatland habitat classes. For all habitat classes except lawn with pools, the predominant classified habitat within 45 m of the center of the validation location was of the same type as the one observed in the field. There were differences in the performance of the two classification procedures: ML was a better tool for mapping rare habitats, whereas WML favored the most common habitats. Based on ordinations, peatland habitat classes were as effective as environmental variables such as humidity indicators and water chemistry components at explaining the distribution of plant species and performed 1.6 times better when it came to accounting for vegetation structure patterns. Peatland habitats with pools had the most distinct plant assemblages, and the habitats dominated by herbs were moderately distinct from those characterized by ericaceous shrubs. Habitats dominated by herbs were the most variable in terms of plant species assemblages. Because peatlands are economically valuable wetlands, the maps resulting from the new classification procedure presented here will provide useful information for land managers and conservationists. <s> BIB001 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> The utility of integrating remotely sensed data and other spatial information in a geographical information system (GIS) to model habitat suitability for nesting by saltwater crocodiles (Crocodylus porosus) was investigated in this study. The study areas, Melacca Swamp and the Adelaide River wetlands, are located 50 km east of Darwin, Northern Territory, and encompass areas of suitable nesting habitat for C. porosus. Melacca Swamp is a highly productive nesting area and is managed as a conservation reserve to protect its nesting habitat. Landsat TM, SPOT satellite imagery and large-scale colour aerial photography were evaluated for their utility in mapping habitats preferred for nesting by C. porosus within Melacca Swamp. Satellite imagery was capable of identifying generalised habitat classes used for nesting (e.g. open swamp with emergent trees). However, it was only with aerial photography that habitats could be discerned (e.g. sedges with scattered Melaleuca trees). Spatial information derived from satellite imagery and other sources was integrated in a GIS to model potentially suitable nesting habitat along the Adelaide River. This methodology effectively identified known preferred nesting areas of C. porosus on the basis of the analysis of environmental parameters (i.e. distance to water, vegetation type) that have an influence on selection of nesting habitat. The findings of this research demonstrate the utility of remote sensing and GIS for mapping nesting habitat of C. porosus at a range of scales and provide guidelines for application of the approaches used at the regional or State level. <s> BIB002 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> Throughout the world, but particularly in tropical regions habitat loss and disturbance are considered detrimental to biodiversity. We examine the effects of disturbance by harvesting, burning and habitat fragmentation on six bird species associated with papyrus (Cyperus papyrus) swamps. The presence or absence of these species was verified in 93 wetlands in southern Uganda between June and August 2003. Disturbance was estimated directly by observation and indirectly from examining vegetation structure. Habitat fragmentation was quantified by delineating swamps on Landsat ETM images and applying ‘Fragstats’ to calculate relevant patch metrics. The occurrence of all six species was affected positively by increased swamp size, but birds were more likely to occur in small swamps at high altitude. The shape and proximity of swamps to neighbouring wetlands had little effect on occurrence. As altitude, habitat fragmentation and disturbance were correlated, determining avian responses to disturbance was problematic. However, the occurrence of all species was affected by disturbance, often showing unimodal responses, if disturbance was not considered in conjunction with habitat fragmentation. When the effects of habitat fragmentation and disturbance were analysed together, only the occurrences of papyrus yellow warbler and white-winged warbler were affected (positively) by disturbance. Results suggest that papyrus-dwelling passerines, except papyrus gonolek, are tolerant of low intensities of disturbance, a novel finding in the tropics. We recommend that policy-makers do not prohibit harvesting, thus generating good will and encouraging rural householders to comply with additional conservation policy. <s> BIB003 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> Abstract We assessed spatial distribution and habitat use by Ross's and lesser snow geese (Chen rossii and C. caerulescens caerulescens) during late brood rearing to begin understanding goose–habitat interactions and monitoring key habitats around a rapidly growing nesting colony located at Karrak Lake, Nunavut, Canada. We conducted aerial surveys to count geese and georeference locations, then used Landsat Thematic Mapper satellite imagery to identify habitats associated with each flock. We observed 435 and 407 flocks and 36,287 and 32,745 birds in 1994 and 1995, respectively. Birds were somewhat uniformly distributed over the 5,000-km2 study area, with larger aggregations occurring closer to the coast, about 70 km from the colony. We assessed habitat use using Bonferroni intervals at both the flock and individual scales. At the flock level, birds avoided lichen–heath, used other terrestrial habitats as available, and selected freshwater. At the individual level, geese selected lowland habitats: wet sedg... <s> BIB004 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> The Madagascar plover Charadrius thoracicus is a shorebird endemic to western Madagascar, currently classified as globally vulnerable. It is restricted to specialized wetland habitats that are increasingly threatened by humans. To inform future conservation measures for this poorly known species, we develop a predictive habitat suitability map and use this map to estimate the size of the Madagascar plover population. We integrate spatially referenced presence-only observations of Madagascar plovers with Landsat data, elevation data and measures of distance to settlements and the coast to produce a habitat suitability model using ecological niche factor analysis. Validation of this model using a receiver operating characteristic plot suggests that it is at least 84% accurate in predicting suitable sites. We then use our estimate of total area of suitable habitat above a critical suitability threshold and data on Madagascar plover density in suitable sites to estimate the total population size to derive a total population estimate of 3100 396 standard error individuals. Finally, we explore the conservation applications of our model. <s> BIB005 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> The southern Oregon-northeastern California and extreme northwestern Nevada (hereafter "SONEC") region provides critical spring migration habitat for waterfowl and other waterbirds in the Pacific Flyway. Information on the dynamics and distribution of waterbird habitats in SONEC during spring is needed to guide conservation efforts in the region. We grouped 1992 National Land Cover Data classes into 5 potential waterbird habitat types and used Landsat 5 Thematic Mapper and Landsat 7 Enhanced Thematic Mapper Plus satellite imagery to map flooding of these habitat types in SONEC during February-May, 2002 and 2003. SONEC included 13,727 km2 of potential waterbird habitat comprised of grasslands (37.1%), pasture/hay (24.6%), marsh (15.9%), open wetland (11.8%), and croplands (10.6%). On average, 11.9% of this potential habitat was flooded during spring; but the percentage, area, and composi- tion varied within and among years and subregions. Total flooding increased from 693 km2 in February to 2099 km2 in April during 2002 and from 1630 km2 in February to 2125 km2 in May during 2003. Open wetland comprised 58%-74%, marsh 8%-18%, pasture/hay 4%-11%, grassland 4%-17%, and cropland 3%-8% of the flooded habitat in SONEC. Satel- lite imagery and land-use data provided useful estimates of waterbird habitat availability in SONEC during spring, but other methods should be tested to more accurately measure flooding of densely vegetated habitats such as marsh. With <12% of the potential habitat flooded on average during spring, conservation programs have ample opportunity to improve the SONEC landscape for migrating waterbirds. <s> BIB006 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> Rice fields are an important habitat for waterbirds. Knowledge of the availability of this habitat is important since the reduction in the area of natural wetlands has converted rice fields into vital refuges. This paper presents a method for mapping habitat availability in rice fields according to different waterbirds’ habitat preferences and examining its phenology during the crop cycle. Data from bird censuses carried out in the Donana rice fields were analysed to determine the habitat preferences of 22 species of waterbird at different stages in the rice production cycle. Discriminant function analysis of seven Landsat images was used to classify paddy field stages. The phenology of habitat availability in rice fields during autumn and winter was examined. Waterfowl and waders preferentially used the ‘flooded’ and ‘mudflats with water’ paddy field stages, respectively, and the ‘rice growing’ and ‘dry’ stages were rejected by waterbirds. The area of preferred habitats within rice fields increased during autumn; subsequently, the area of the ‘flooded’ paddy fields decreased in January, whereas that of ‘mudflats with water’ remained available until March. The automatic classification of paddy field stages with Landsat images allowed habitat availability for different species of waterbirds to be monitored and provides relevant information for understanding behavioural and population responses in waterbirds that use rice fields. After examining the phenology of the availability of habitat and comparing it with dates of arrival and departure of migrant waterbirds, best crop practices could be defined to favour waterbirds (i.e. adjusting harvest, ploughing and flooding dates). Taking into account climatic change and loss of wetlands this method could help in the integration of agriculture and conservation, in particular in areas where there is no remaining natural wetland habitat. <s> BIB007 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> Bird monitoring is frequent in wetlands; however, in the absence of information on other variables, trends in bird numbers are difficult to interpret. In this article we describe a methodology for bird’s habitat area assessment based on remote sensing. We calibrated the methodology to study the changes in the habitat area of Cygnus melancoryphus, the black-necked swan, at the Carlos Anwandter Sanctuary, a wetland located in Valdivia, Southern Chile. Swan habitat area was estimated by means of the Normalized Difference Vegetation Index (NDVI) based on Landsat images and calibrated through spectral photography by means of a portable Tetracam ADC Camera. Results show that calibrated NDVI values from Landsat images can be used to estimate habitat area but not to separate individual species of vegetation. We also show that the joint analysis of habitat area and swan count can indeed be used to separate some of the scales of variability of bird counts: those with “local-influence” associated with changes in habitat area from those of larger scales not related with habitat area. <s> BIB008 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> As wildlife habitat is in constant evolution, periodic monitoring is essential to assess its quality. In this study, the change to the red-crowned crane habitat in the Yellow River Delta Nature Reserve was detected from multi-temporal remote sensing data from 1992 to 2008 in a geographic information system. Habitat fragmentation was derived from both physical constraints and human disturbance. The changing habitat quality was assessed against five landscape indices. The results obtained from Landsat TM images indicate that potential habitat shrank 37.9 % during 1992–2001, but recovered 99.4 % by 2008. Suitable habitat shrank by 4,329 ha to a level below that of 1992 despite an increase of 4,747 ha in potential habitat due to an increase of 9,075 ha in fragmented areas. Both landscape indices and the red-crowned crane population reveal that suitable habitat was the most fragmented in 2001, but the least fragmented in 1992. Therefore, it is inadequate to just restore wetland through artificial diversion of channel flow to the Reserve to preserve the crane habitat. Commensurate efforts should also be directed at improving habitat quality by minimizing human activities and spatially juxtaposing water and reed marshes harmoniously inside the Reserve. <s> BIB009 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> Assessment of habitat quality for wetland-obligate wildlife and endangered species of waterfowl is essential particularly in the changing environment. In this study, the areas of potential suitable habitat for Siberian cranes in Poyang Lake natural wetland were evaluated using 11 scenes of Landsat TM/ETM+ images. Habitat quality was assessed against six landscape indices. Results indicate that the optimum water level for habitats of Siberian cranes in Poyang Lake wetland would be about 12 m. Potential suitable habitat areas would be reduced from about 2300 km2 at 5 m lake level to 530 km2 at 15.6 m lake level. Landscape indices revealed that a higher water level would not be suitable for conservation of Siberian cranes. The proposed Poyang Lake Dam should be operated to control water levels for providing a favorable habitat condition for wintering migratory birds. It would create an unfavorable condition to the wintering habitats for Siberian cranes in Poyang Lake wetland if the dam would maintain the lak... <s> BIB010 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> The concept of habitat networks represents an important tool for landscape conservation and management at regional scales. Previous studies simulated degradation of temporally fixed networks but few quantified the change in network connectivity from disintegration of key features that undergo naturally occurring spatiotemporal dynamics. This is particularly of concern for aquatic systems, which typically show high natural spatiotemporal variability. Here we focused on the Swan Coastal Plain, a bioregion that encompasses a global biodiversity hotspot in Australia with over 1500 water bodies of high biodiversity. Using graph theory, we conducted a temporal analysis of water body connectivity over 13 years of variable climate. We derived large networks of surface water bodies using Landsat data (1999–2011). We generated an ensemble of 278 potential networks at three dispersal distances approximating the maximum dispersal distance of different water dependent organisms. We assessed network connectivity through several network topology metrics and quantified the resilience of the network topology during wet and dry phases. We identified ‘stepping stone’ water bodies across time and compared our networks with theoretical network models with known properties. Results showed a highly dynamic seasonal pattern of variability in network topology metrics. A decline in connectivity over the 13 years was noted with potential negative consequences for species with limited dispersal capacity. The networks described here resemble theoretical scale-free models, also known as ‘rich get richer’ algorithm. The ‘stepping stone’ water bodies are located in the area around the Peel-Harvey Estuary, a Ramsar listed site, and some are located in a national park. Our results describe a powerful approach that can be implemented when assessing the connectivity for a particular organism with known dispersal distance. The approach of identifying the surface water bodies that act as ‘stepping stone’ over time may help prioritize surface water bodies that are essential for maintaining regional scale connectivity. <s> BIB011 </s> A Review of Wetland Remote Sensing <s> Habitat/Biodiversity <s> In this study we produced the first thematic maps of submerged and coastal habitats of Lampi Island (Myanmar) from in situ and satellite data. To focus on key elements of bio-diversity typically existing in tropical islands the detection of corals, seagrass, and mangrove forests was addressed. Satellite data were acquired from Landsat-8; for the purpose of validation Rapid-Eye data were also used. In situ data supporting image processing were collected in a field campaign performed from 28 February to 4 March 2015 at the time of sensors overpasses. A hybrid approach based on bio-optical modeling and supervised classification techniques was applied to atmospherically-corrected Landsat-8 data. Bottom depth estimations, to be used in the classification process of shallow waters, were in good agreement with depth soundings (R2 = 0.87). Corals were classified with producer and user accuracies of 58% and 77%, while a lower accuracy (producer and user accuracies of 50%) was found for the seagrass due to the patchy distribution of meadows; accuracies more than 88% were obtained for mangrove forests. The classification indicated the presence of 18 mangroves sites with extension larger than 5 km2; for 15 of those the coexistence of corals and seagrass were also found in the fronting bays, suggesting a significant rate of biodiversity for the study area. <s> BIB012
Wetlands are considered a wildlife habitat. Some types of endangered birds are restricted to specialized wetland habitats. Habitat loss and degradation due to climate change and human activities greatly threaten waterfowls. Climate change, such as frequent drought, could cause the shrinkage of wetland area; human activities, such as wetland reclamation and water conservancy engineering, are thought to be the reasons for habitat loss and degradation and threaten the survival of waterfowls BIB010 . As a medium-resolution sensor, Landsat data have been considered to be an effective method in habitat research of wildlife in wetlands at a large area, especially because of time scales >30 years. Tulbure et al. BIB011 used Landsat data to derive surface water bodies and then identify the "step stone" of water-dependent organisms to maintain landscape connectivity. Toral et al. BIB007 used Landsat data to identify rice paddy stages and mapped the habitat availability of water birds in rice fields. Discriminant function analysis was used for Landsat images and different paddy field stages; the habitats of different species of water birds were obtained. Their results are important for water bird conservation, especially in regions with small areas of natural wetland habitat. Jiang et al. BIB010 evaluated the habitat for Siberian cranes of the Poyang Lake wetland in China using Landsat data and found that the suitable water level is 12 m. Their results have practical significance for controlling the water level of the Poyang Lake Dam. Delgado and Marín BIB008 used NDVI derived from Landsat data to assess the habitat of the black-snacked swan. Wang et al. BIB009 assessed the habitat quality of the red-crowned crane in the Yellow River Delta Nature Reserve of China using Landsat data. They concluded that human activity should be minimized to improve the habitat quality for red-crowned crane. Human activities disturb the ecosystem, which will affect the survival of bird species. Maclean et al. BIB003 examined the relationships between harvesting, burning, and habitat fragmentation of swamps and six bird species and found a positive correlation. With the increase of swamp areas, all six bird species increased; however, but no correlation was observed depending between the shape and proximity of swamps and bird species. Landsat and land cover data can provide estimates for water bird habitats in wetlands; the dynamics and distribution of water bird habitats are essential for conservation BIB006 . A reliable wetland habitat map is required by ecologists and conservationists; however, different methods applied to the Landsat data could lead to results with different accuracies. Poulin et al. BIB001 reported that the simple maximum likelihood (ML) function is suitable to map rare wetland habitat and the weighted maximum likelihood (WML) function is more suited for common habitats. To guide the conservation of endangered shorebirds in the future, The population of shorebirds and their suitable habitat should be understood. Many scholars modeled species-habitat relationships based on wildlife observation and habitat data. Long et al. BIB005 mapped a suitability habitat for a type of shorebird using Landsat data and then estimated the number of shorebirds. Slattery and Alisauskas BIB004 used Landsat TM data to monitor the snow geese habitat and estimated the spatial distribution and habitat use in flock and individual scales of snow geese. Giardino et al. BIB012 mapped the coastal and submerged habitat using Landsat 8 OLI and in situ data to study the principal element of biodiversity. Harvey and Hill BIB002 and Duffett et al.  modeled the nest habitat of saltwater crocodiles using Landsat TM, SPOT, and aerial photography and Matthews  assessed bison habitat using Landsat TM data.