Economic Impacts of Red Tide Events on Restaurant Sales

The economic impact of red tide events were examined for three Southwest Florida waterfront restaurants. Daily gross sales from January 1996 through September were analyzed using a multiple regression time series model to examine whether the presence of a red tide, as measured within three and six miles of the beach, reduced sales revenues. Preliminary results indicate that red tide blooms closer to shore had a significantly large negative influence on sales revenues across restaurant locations.Agribusiness,

Discovering and Generating Hard Examples for Training a Red Tide Detector

Currently, accurate detection of natural phenomena, such as red tide, that adversely affect wildlife and human, using satellite images has been increasingly utilized. However, red tide detection on satellite images still remains a very hard task due to unpredictable nature of red tide occurrence, extreme sparsity of red tide samples, difficulties in accurate groundtruthing, etc. In this paper, we aim to tackle both the data sparsity and groundtruthing issues by primarily addressing two challenges: i) significant lack of hard examples of non-red tide that can enhance detection performance and ii) extreme data imbalance between red tide and non-red tide examples. In the proposed work, we devise a 9-layer fully convolutional network jointly optimized with two plug-in modules tailored to overcoming the two challenges: i) a hard negative example generator (HNG) to supplement the hard negative (non-red tide) examples and ii) cascaded online hard example mining (cOHEM) to ease the data imbalance. Our proposed network jointly trained with HNG and cOHEM provides state-of-the-art red tide detection accuracy on GOCI satellite images.Comment: 10 page

A Red Tide Monitoring Program for Texas Coastal Waters

This is the final report for the red tide monitoring project conducted at The University of Texas at Austin Marine Science Institute (UTMSI) and covers the period from 1 Nov. 1998 to 10 April 2000. The study was designed to examine the seasonal dynamics of the toxic red tide dinoflagellate Karenia brevis (Davis) G. Hansen and Moestrup at 5 locations off the Texas coast. The work was conducted in collaboration with the Texas Parks and Wildlife Department (TPWD) utilizing bimonthly finfish surveys (Coastal Fisheries Division) to collect samples. The samples were shipped to UTMSI for chl a, nutrient, and cell count analyses. Significant interannual variability occurred in the temperature and salinity fields. Temperature was lowest in Jan.-Feb. of each year and increased. In general, the 5 stations showed little concordance with each other. There was no annual pattern in nutrient distributions. Individual stations appeared to reflect local inputs, rather than coast wide events. The only exception was a generalized silicate increase noted in Feb-April 2001 at all stations except Brazos Santiago near Brownsville. Karenia brevis was observed sporadically along the coast during the winter and most observations were limited to the summer/fall months. The sporadic occurrences and numerous "no cells" observations do not support the hypothesis that a year round resident red tide population exists in the Texas coastal zone. It appears that are transported into the area by large scale oceanographic features. The mechanism for this remains unknown. A minor red tide occurred along South Padre Island in Oct./Nov 1999. The bloom advected south into Mexico, and no further fish kills were noted in 1999. However, K. brevis occurred sporadically along the coast during this time. These events suggest that K. brevis may be seeded into the area from further offshore regularly at very low levels. Until fish-killing populations develop, it likely remains undetected. One major red tide event occurred during 2000 that affected the entire Texas coast. A small red tide occurred along South Padre Island in July, 2000 but disappeared after moving north to Padre Island National Seashore. Fish-killing concentrations of K. brevis were first detected in mid August off Sabine Pass in the north and moved south along the coast over the following months. However, low level occurrences of K. brevis were found at intermediate stations well before the main red tide advected into the region, and were nearly coincident with the initial observations off Sabine Pass. It is impossible from this data to determine if the July bloom in south Texas was related to the events off Sabine, but there is a possibility that offshore continental shelf currents may well be transporting cells north from Mexico into northern Texas waters. Another toxic species closely related to K. brevis has been seen at reasonably high abundance. This species, Karenia mikimotoi, is toxic to fish and has been reported to co-occur with K. brevis in blooms. Maximum abundance of this species was 6000 cells L-1, and appeared to exhibit a distinct increase and decline in population levels at 3 different stations.Marine Scienc

Collective motion of micro-organisms from field theoretical viewpoint

We analyze the collective motion of micro-organisms in the fluid and consider the problem of the red tide. The red tide is produced by the condensation of the micro-organisms, which might be a similar phenomenon to the condensation of the strings. We propose a model of the generation of the red tide. By considering the interaction between the micro-organisms mediated by the velocity fields in the fluid, we derive the Van der Waals type equation of state, where the generation of the red tide can be regarded as a phase transition from the gas of micro-organisms to the liquid

Red tide

Algae are vitally important to marine ecosystems, and most species of algae are not harmful. However, under certain environmental conditions, microscopic marine algae called Karenia brevis (K. brevis) grow quickly, creating blooms that can make the ocean appear red or brown. People often call these blooms \ue2\u20ac\u153red tide.\ue2\u20ac?K. brevis produces powerful toxins called brevetoxins, which have killed millions of fish and other marine organisms. Red tides have damaged the fishing industry, shoreline quality, and local economies in states such as Texas and Florida. Because K. brevis blooms move based on winds and tides, pinpointing a red tide at any given moment is difficult.Red tides occur throughout the world, affecting marine ecosystems in Scandinavia, Japan, the Caribbean, and the South Pacific. Scientists first documented a red tide along Florida\ue2\u20ac\u2122s Gulf Coast in fall 1947, when residents of Venice, Florida, reported thousands of dead fish and a \ue2\u20ac\u153stinging gas\ue2\u20ac? in the air, according to Mote Marine Laboratory. However, Florida residents have reported similar events since the mid-1800s

Red Tide: Bad for Business?

Red Tide is a harmful algal bloom that has been observed off the Gulf Coast of Florida for decades. The damage caused by red tides can be seen from beaches to local businesses to shellfish farmers. Research to learn more about how red tide is formed and how to mitigate the effects is a multi-million-dollar effort connecting scientists from all different parts of the world. While no solution has yet been found for a problem of this magnitude, several methods have been proposed and are undergoing experimentation. Looking at the effects red tide has on the state of Florida may provide a better understanding as to why finding a solution for red tide is a pressing issue

NH Department of Helath and Human Services Public Health Laboratories Shellfish Program Activites January 2006 – December 2006

The Department of Health and Human Services-New Hampshire Public Health Laboratories (DHHS-NHPHL) has continued to carry out various actions providing laboratory analyses for the routine water quality monitoring, “Red Tide” monitoring, and additional testing after rainfall, excess sewage treatment plant, and emergency events