Batfish profilers

Two Batfish profiles of chlorophyll and copepods (sampled in the eastern Canadian Arctic) were separated by volume into their component species and are shown in Figure 5. The separation shows that both Calanus finmarchicus Stage V and Calanus glacialis Stage V are situated 5 m above the chlorophyll maximum, whereas Calanus hyperboreus Stages V and VI were situated primarily at or below the chlorophyll maximum. Such examples illustrate the species identification potential of the electronic counter and the resolution capabilities of the system for isolating species in the water column. 

Figure 5. Two Batfish profiles of copepods, chlorophyll, temperature, and salinity. The chlorophyll maximum is located at the base of the thermocline...

Figure 6. Scotian Shelf and slope-water region. The mean position of a thermal front with surface temperatures of -- 9-11 °C was contoured from satellite imagery and partly from Batfish profiling. The work area for Batfish transects is shown along 63°25 W (10).

Figure 10. Vertical Batfish profiles taken from the transect of Figure 6 on the Scotian Shelf. The profiles are separated into the following components chlorophyll, production estimated in two Ways from a chlorophyll/ light model, small copepods (S.C.), and all stages of C. finmarchicus (13).

Figure 11. The depth of maximum chlorophyll, production relative to small copepods, and C. finmarchicus. The tow began in coastal waters of the Scotian Shelf (left side of plot) and the course was reversed at the front. There are -- 90 vertical Batfish profiles in the transect (13).

Biological Profiling in the Upper Oceanic Layers with a Batfish Vehicle A Review of Applications... 

HERMAN Biological Profiling with a Batfish Vehicle... 

Figure 8, Time sequence of temperature profiles of the front south of Nova Scotia taken by Batfish over —30 /i. A bimodal intrusion occurs in Panel 4 at...

Separation of the vertical interactions of copepods and chlorophyll requires a measurement resolution of — 1 m. Such a requirement was apparent in the Arctic data, which indicated small vertical separations of — 3-4 m between copepods and chlorophyll. Continuous profiling with the Batfish provides adequate statistical sampling of a large number of profiles... 

The in situ Batfish sampler does not provide seawater samples for on-deck analysis. Therefore, we have also developed a continuous profiling pumping system (11) that measures biological profiles of copepods and chlorophyll and temperature while on station. Copepods and chlorophyll are measured on deck from the hose effluent with a deck-mounted electronic zooplankton counter and Turner 111 fluorometer. Measured profiles of copepods and chlorophyll indicate a vertical resolution of 3-4 m while the pumping system delivers — 50-60 L/min of seawater on deck. 

Herman, A.W. and Denman, K.L. (1976). Rapid underway profiling of chlorophyll with an in situ fluorometer mounted on a batfish vehicle. Deep-Sea Res., 24,385-397. 

---