Figure 1.  Below. Seascape distributions during the week before (March 4-11) and during the cruise (March 11-18). Colors correspond to individual seascape types. The FKNMS limits are shown with the black line and sampled sites during the cruise are shown with black circles. Right: underway measurements of CDOM and Chl-a fluorescence, salinity, turbidity, and phycoerithryn and phycocyanin fluorescence.

Figure 3. Below. Sampled locations (circles) showed various levels of seascape heterogeneity within a 9-km radius area (shown with crosses).

Figure 2. Below. In situ Chl-a, specific absorption of phytoplankton (aph), detritus (ad), and CDOM (ag), and harmful algal blooms (HABs) counts from the FWC HAB program at selected sampling sites during the March 14-18 cruise.

Figure 4. Below. Principal component analysis of common phytoplankton measured as part of the FWC HAB monitoring program. Color code denotes seascape from which the sample was taken. PC1 is associated with increased Pseudonitzschia sp. abundance, PC 2 is associated with increased dominance by Karenia brevis (increases met with declines in other species), PC3 is associated with increased Procentrum spp. abundances.

The satellite seascape maps (8-day composites) were developed for the week before the cruise (March 4-11) and during the cruise (March 11-18) to study the spatiotemporal evolution of seascapes across the region.  Eight seascape types were sampled across      27 stations for hydrography, eDNA, phytoplankton taxonomy, and bio-optical properties (Fig 1). 

Seascape distributions were compared to concurrent underway observations (Fig. 1) and discrete observations of chlorophyll-a concentrations, specific absorption of phytoplankton, detritus, and colored dissolved organic matter (CDOM), and harmful algae counts from the Florida Wildlife Conservation Commission HAB program (Fig. 2). Seascape types were somewhat variable within a 9-km radius area at some stations, whereas other sites exhibited highly homogeneous seascape conditions (Fig. 3).  Also, three seascape types had distinctive HAB assemblages (Fig. 4).

Zooplankton samples are collected routinely during the RV Walton Smith cruises to test molecular detection of zooplankton using eDNA methods. During the March cruise, triplicate net tows for zooplankton sampling were also added to reduce sample biasing for zooplankton diversity estimates for our eDNA detection tests.

Research In Progress: Team Uses Satellite Seascapes to Guide Florida Keys Sampling

MBON researchers tested a new sampling plan strategy based on satellite seascape maps created by Maria Kavanaugh, Postdoctoral  Investigator at the Woods Hole Oceanographic Institution. The seascape maps guided the sampling during the RV Walton Smith cruise in the Florida Keys National Marine Sanctuary in March 2016.

"Our goal was to identify relationships between in situ biodiversity observations and distributions of various seascape types. Sampling different seascapes allows us to compare how biodiversity of different trophic levels is influenced by changes in ocean chemical and physical properties derived from ocean color data," said Enrique Montes Herrera, post-doctoral researcher at USF,  who works with Kavanaugh and others in Muller-Karger's Institute of Marine Remote Sensing at USF, to process the satellite images. "We made changes in the sampling plan for eDNA to target different seascape types."

Montes and Muller-Karger oversee the MBON Florida Keys sampling program in collaboration with NOAA AOML partners Chris Kelble, Lindsey Visser and Libby Johns.  The sample collection and processing in FKNMS Key West facility is conducted by NOAA FKNMS scientists including Lonny Anderson, Rosemary Abbitt, Beth Dieveney and overseen by Sean Morton.