Ginger Tiling-Range
Due to the vast amount of mangrove shoreline in southwest Florida, its entirety cannot be examined in this pilot project. We propose to examine three areas within southwest Florida where Pristis pectinata has been found (based on the sighting and capture data-set provided by the National Oceanic and Atmospheric Administration). From north to south along the coast these will be: the lower Caloosahatachee River and Matlacha Pass; the 10,000 Islands from Goodland to Fakahatchee Bay, including the lower Faka-Union Canal; and from Lostmans River to Shark River in Everglades National Park. These three areas have differing mixes of mangrove shoreline types and thus present an excellent opportunity to examine utilization of shorelines by sawfish. More importantly, they comprise a gradient of human impacts on shorelines, with greatest modification to shorelines in the Caloosahatchee and least in the Lostmans - Shark Rivers.
U.S. Department of Agriculture - Natural Resources Conservation Service (NRCS) Department of the Interior - U.S. Geological Survey Department of Commerce - National Oceanic and Atmospheric Administration (NOAA) Environmental Protection Agency (EPA) Smithsonian Institution - National Museum of Natural History (NMNH)
Foster, Ann M.; Briere, Peter R.; Jones, John W.; Van Arsdall, Carson
Foster, Anne M.; Briere, Peter R.; Coffin, Alisa W.; Jones, John W.; Van Arsdall, Carson; Frye, Laurinda J.
Poulakis, G. R.
Poulakis, G. R.
The full article is available via journal subscription or single article purchase. The abstract may be viewed on the Science Direct website by selecting the volume and issue number.
Osborne, J.; Schmidt, T. W.
The full article is available via journal subscription or single article purchase. The abstract may be viewed on the Science Direct website by selecting the volume and issue number.
Schall, T. N.; Doren, R. F.; Atkinson, A.; Ross, M. S.; Jones, D. T.; Madden, M.; Vilchek, L. Bradley, K. A.; Snyder, J. R.; Burch, J. N.; Pernas, T.; Witcher, B.; Pyne, M.; White, R.; Smith III, T. J.; Sadle, J.; Smith, C. S.; Patterson, M. E.; Gann, G. D.
An arbitrary limit of 200 m was chosen for classifying a sighting as being along a shoreline. Every sighting 200 m or less was considered adjacent to a shoreling and the nearest shoreline was classified. Sightings greater than 200 m were classified as open water and recorded so that a shoreline could be assigned later if needed.
The frequency distribution of shoreline types will be determined using the following method. Random points within the three study areas will be generated using ArcGIS. The nearest shoreline to each point will be located and then classified using the scheme above. The location of each classified shoreline point will be recorded and a shape-file of classified points will be developed. This procedure will be repeated three times for each study area and for each year (1940 and 2004). The number of random points will be from 50 to 100.
New boundaries were created for each study area and 300 randomly generated points were created in each of the study areas.
Historic aerial photos have been collected, scanned and georeferenced for each of the study areas and the historic photos were superimposed on the modern Digital Orthophoto Quarter Quadrangles (DOQQ) for analysis of habitat change.
A draft shoreline classification has been developed. Three levels of classification are proposed. The level one classifier is Natural versus Impacted. The second level classifier is Vegetated versus Un-vegetated. Within the Vegetated class, sub-classes include mangrove, marsh, mixed wetland, and upland. In the Un-vegetated class, subclasses include beach and reef. For "Impacted - Vegetated" a subclass was added for the presence of exotic species on the shoreline. For "Impacted - Un-vegetated" the sub-classes are spoil, concrete and rubble. The third classifier is depth with shallow and deep as the sub-classes.
Three separate databases for each study areas were created. Data stored in each database includes mosaiced DOQQs, mosaiced historic photos, Smalltooth Sawfish, Pristis pectinata data, shorelines, Collison Regulations from the Convention on the International Regulations for Preventing Collisions at Sea of the International Maritime Organization (colregs), random points, bathymetry data.. In our case there is a "colregs" line drawn at the mouth of most rivers. We used some of the colregs demarcations as our boundaries.
Two field reconnaissance trips were undertaken to ground-truth some initial shoreline classifications based on the aerial photos. One trip was by vehicle around the Caloosahatchee River where we attempted to locate shorelines adjacent to known sawfish sightings in the Cape Coral canal system (without trespassing on private property). The second trip was by boat in the 10,000 Islands National Wildlife Refuge
Several errors were discovered in the bathymetry data set. Therefore, we went through the complete dataset and checked polygon by polygon to see if they agreed with our interpretation which based on the 2004 imagery and the bathymetry in the National Sawfish Encounter Database (NSED) dataset. Inspection of the bathymetry dataset resulted in three polygons being changed.
Completed classification and QA/QC of the 300 random shoreline points for the 10,000 Islands and Lostmans - Shark River study areas, for both historic and present day eras (1,200 total points classified).
Completed change analyses of the classified shorelines for these study areas.
Conducted statistical analyses of the classified points for the 10,000 Islands and Lostmans - Shark Rivers study areas.
Incorporated the newly updated NSED into our geo-database for each of the three study areas.
Classified shorelines associated with sawfish for the 10,000 Island and Lostmans - Shark River study areas.
Performed QA/QC on the sawfish shorelines.
Conducted preliminary analyses of the relationship of sawfish sightings to shoreline class for both study areas.
Completed acquiring the historic air photos for the Caloosahatchee - Matlacha study area.
Geo-referenced and mosaiced these images and incorporated the mosaic into the geo-database.
Added the "negative" collection data to the geo-database.
In the original sawfish dataset we were provided, juveniles were not separated by size-class. In the latest version of NSED, juveniles are separated into Large (201 - 330 cm), Small (100 - 200 cm) and Very small (<100 cm) size-classes. We have analyzed sawfish sightings by this size-class distinction. Our analysis dealt with sightings" which could involve more than one sawfish. We did not weight the analysis based on number counted during a sighting .
A number of sawfish sightings in NSED dataset are for individuals well off-shore, with several >1,000 m from shore. We arbitrarily set a limit of 200 m for classifying a sighting as being along the shoreline. Every sighting 200 m or less was considered adjacent to a shoreline and the nearest shoreline was classified. Sightings >200 m were classed as "open water". We recorded these "open water" points so that a shoreline class can be assigned at a later date if it is decided to do so.
In the Lostmans - Shark river area both Small and Very small sawfish appeared to be over-represented along Natural - Mangrove - Shallow and Natural - Beach - Shallow shorelines and juveniles appear to be under-represented along Natural - Mangrove - Deep shorelines.
These two conditions above are most likely a result of how the NSED is put together. Most sightings are from recreational fisherman or researchers who are fishing in the shallow flats, and not in deeper channels, and end up catching or seeing a sawfish.
In the 10,000 Islands study area sightings are very much over-represented for the Altered - Mangrove - Shallow class. This point was discussed at the Implementation Team meeting and is the result of researchers catching large numbers of all sized juveniles around mangrove spoil islands off the mouth of the Faka-Union Canal
Start and finish the shoreline classification for the random points in the Caloosahatchee - Matlacha study area for both the historic (1944) and modern (2004) periods.
Conduct change analysis of the Caloosahatchee - Matlacha study area.
Conduct the shoreline classification of the NSED sightings for the Caloosahatchee - Matlacha study area.
Conduct analyses of sawfish sightings for both un-weighted (i.e. each sighting = 1) and weighted (i.e. sighting multiplied by number of sawfish recorded in the event) for all three study areas.
Analyze the shorelines of successful and unsuccessful capture locations for differences.
Provide all GIS data-layers, graphics, the geo-databases and all ancillary data and graphics to NOAA.
U.S. Department of the Interior, U.S. Geological Survey
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