Quote:
Originally Posted by Duvalboomer
Fish kill in some of the ponds due to temperature inversion from all of the rain
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I just found this:
A sudden appearance of dead fish in a lake or pond causes considerable concern and alarm for most people. Our first reaction is to suspect poisoning of the waterbody. Most fishkills,however, result from natural events, although people can influence their frequency and severity.
Fish kills usually result from too little oxygen in the water.
South Florida receives between 150 and 200 fish kill reports each year.
While some result from spills or illegal discharges of toxic substances, most kills occur when OXYGEN dissolved in the water drops to levels insufficient for fish survival.
For a dissolved oxygen of DO-related fish kill to occur, a combination of environmental conditions transpire simultaneously.
WEATHER PATTERNS, water temperature, depth and quality, amount and type of plant growth, fish community structure, along with the presence of viruses and bacteria are all factors that are necessary to trigger a fish kill.
Lakes, ponds and canals located in RESIDENTIAL AREAS are particularly vulnerable to DO related fish kills. Developed areas create runoff that contain high amounts of nutrients from SEPTIC TANKS.
In addition, street and yard drainage that enters waterbodies can cause water quality problems...
High levels of nutrients from fertilizers applied to lawns, golf courses and farms cause aquatic plants to thrive......
Ponds with high nutrient levels produce dense growths of microscopic plants called ALGAE.
When sunlight is available, algae use nutrients and produces oxygen through the process of photosynthesis. Most oxygen available to fish comes from algae.
DURING NIGHT TIME and cloudy weather, low sunlight causes algae to switch from photosynthesis to respiration, consuming oxygen needed by fish. During severe events, fish can suffocate from low DO.
Most frequently, fish become stressed during a low DO period and become susceptible to viral or bacterial infections.
Most fish kills occur in the warmer months of May through September.
Usually after a period of RAINY or cloudy weather.
Application of pesticides to control lawn and crop insects can enter a pond during heavy rains and cause a fish kill.
FISH KILLS CAN ONLY BE PREVENTED BY MAINTAINING GOOD WATER QUALITY.
CLEAN UP OF FISH KILLS OCCURING IN PRIVATE RESIDENTIAL LAKES AND CANALS ARE GENERALLY THE RESPONSIBILITY OF THE PROPERTY OWNER OR HOMEOWNERS ASSOCIATION.