The Book Kills

[Derrick Drescher]

Fishkills and fish disease events in North Carolina often involve a host of factors and underlying causes. It is therefore crucial to gather as much information as possible surrounding an event from all involved parties. In 1996 the DWR Water Sciences Section (WSS), in consultation with Regional Office staff, Wildlife Resources biologists, and Division of Marine Fisheries personnel instituted a new fish kill investigation procedure to be used by the DWR Regional Offices, Monitoring Teams and other agencies to collect and track information on fish kills throughout the state. Fish kill and fish health data are recorded via standardized methods and sent to WSS where the data are reviewed. Fish kill investigation reports and supplemental information are compiled in a central database where the data can be managed, retrieved, and reported to state officials, scientists, and other concerned parties. Fish kill data is also reviewed as part of the DWR efforts to monitor water quality trends across the state.

The Texas Parks and Wildlife Department Kills and Spills Team (KAST) is a group of biologists who investigate fish and wildlife kills resulting from pollution and natural events. KAST staff are trained to assess impacts to fish and wildlife resources and to determine the causes of events.

Some of the most common calls fishery management agencies receive from the public are reports about dead or dying fish in a waterbody, or fish kills. A fish kill is a common but complex phenomenon. Contrary to popular belief, fish kills are seldom caused by pollution or other human activities. Instead, changes in environmental factors such as temperature, dissolved oxygen, salinity, and acidity are often to blame for fish kills. Changes in some of these factors might not be lethal by themselves, but when combined, can cause a fish kill. In many reported fish kills, it is not possible to determine the cause.

In Louisiana and other areas of the southern United States, fish kills occur most frequently in the summertime. The most common cause of summertime fish kills is low levels of dissolved oxygen in the water. Fish need oxygen to survive and almost all fish get their oxygen from the water. When dissolved oxygen levels are low, fish can suffocate and die.

While hundreds of fish kills occur in Minnesota every year, mostly in lakes and ponds, fish kills on trout streams in southeast Minnesota are much less common. The cause of most lake/pond fish kills is believed to be from natural causes such as disease or low oxygen levels under ice. These natural causes, however, may be exacerbated by chronic environmental conditions such as excess nutrients in lakes, and extreme weather.

In trout streams, fish kills are usually related to the discharge or runoff of pollutants from the landscape through incidents like toxic spills, runoff of manure, pesticides, or fertilizers, and high-temperature wastewater or stormwater discharges.

If you see multiple dead fish in a lake or river, or runoff or a spill entering waters, call the Minnesota Duty Officer at 800-422-0798. Calls are answered 24 hours a day, 365 days a year. If there is an immediate threat to life or property, call 911 first.

Timing is critical to test waters or capture spills. Key investigative elements such as water levels, water temperature, water quality, and amount or type of run off can quickly move downstream and dilute, leaving little evidence.

Smart application of manure, pesticides and fertilizers is critical to maximize their nutrient value and increase crop productivity. Runoff from fields not only reduces crop productivity but may impact water quality and could contribute to fish kills, especially when improperly applied or applied too close to rain events.

The MPCA, Department of Natural Resources (DNR), Department of Agriculture (MDA), and Department of Health (MDH) coordinate on fish kill responses. Agency program staff coordinate and triage fish kill reports to determine the appropriate level of response and investigation for each. The DNR makes initial assessments regarding reports that indicate likely winterkill or summerkill. When a fish kill presents a threat to public health and safety, MDH will get involved. The MDA takes the lead for pesticide and fertilizer incidents while the MPCA investigates the environmental impacts from the release of hazardous materials, oil, or other materials such as manure. Local governments also help with fish kill investigations.

Some fish kills have obvious causes, such as a spill or identifiable discharge to a surface water. One example is when a tanker truck tips over in a ditch, spilling a product toxic to fish that flows to a stream. Other fish kills have less discernible causes that are often driven by rain events somewhere in a watershed. An example would be an intense rain event that creates runoff to streams from many agricultural fields and city streets in a large upstream watershed. Finding a clear explanation for a fish kill will depend largely on the lag time between the kill and its reporting, as well as the complexity and scope of the cause(s).

As described in Iowa DNR's current methodology for water quality assessments, occurrence of a single pollutant-caused fish kill, or a fish kill of unknown origin, on a waterbody or portion of a waterbody during the most recent three-year period indicates an impairment of the aquatic life uses.

Each report of a fish kill will be reviewed to determine whether development of a TMDL is appropriate. In the absence of an ongoing source of a pollutant, TMDLs will not be developed for kills caused by a one-time illegal or unauthorized release of manure or other toxic substance. Impacts from this type of fish kill are addressed through IADNR's enforcement procedures. Fish kills attributed to authorized discharges (i.e., a discharge meeting permit limits) are considered for Section 303(d) listing as the existing, required pollution control measures are not adequate to address this impairment.

The advent of 305(b) reporting and Impaired Waters Listings caused the TMDL and Water Quality Assessment section to begin tracking fish kills and their causes to a greater degree than before. A fish kill can affect the 305(b) water quality assessment of the waterbody, and can potentially cause the waterbody to be listed on the 303(d) listing of impaired waters.

The occurrence of a single pollutant-caused fish kill, or a fish kill of unknown origin, on a waterbody or portion of a waterbody during the most recent three-year period indicates an impairment of the aquatic life uses. This "once in three-year" frequency of criteria violation is designed to provide protection for ecological recovery from a severe stress and is consistent with U.S. EPA recommendations.

Each report of a fish kill will be reviewed to determine whether development of a TMDL is appropriate. In the absence of an ongoing source of a pollutant, TMDLs will not be developed for kills caused by a one-time illegal or unauthorized release of manure or other toxic substance. Impacts from this type of fish kill are addressed through IADNR's enforcement procedures. Fish kills attributed to authorized discharges are considered for Section 303(d) listing as the existing, required pollution control measures are not adequate to address this impairment.

If you believe a fish kill has occurred, please contact the nearest DNR Field Office or Fisheries Office. You should have available the name of the stream, the location of the kill, and any other conditions or observations that may aid in the investigation of the cause and source of the kill.

This section offers statewide records of current and historic information about reported external abnormalities in fish and fish kills reported to the Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute.

The tobacco epidemic is one of the biggest public health threats the world has ever faced, killing over 8 million people a year around the world. More than 7 million of those deaths are the result of direct tobacco use while around 1.3 million are the result of non-smokers being exposed to second-hand smoke (4).

All forms of tobacco use are harmful, and there is no safe level of exposure to tobacco. Cigarette smoking is the most common form of tobacco use worldwide. Other tobacco products include waterpipe tobacco, cigars, cigarillos, heated tobacco, roll-your-own tobacco, pipe tobacco, bidis and kreteks, and smokeless tobacco products.

Around 80% of the 1.3 billion tobacco users worldwide live in low- and middle-income countries (5), where the burden of tobacco-related illness and death is heaviest. Tobacco use contributes to poverty by diverting household spending from basic needs such as food and shelter to tobacco. This spending behaviour is difficult to curb because tobacco is so addictive.

The economic costs of tobacco use are substantial and include significant health care costs for treating the diseases caused by tobacco use as well as the lost human capital that results from tobacco-attributable morbidity and mortality.

Good monitoring tracks the extent and character of the tobacco epidemic and indicates how best to tailor policies. Almost half of the world's population are regularly asked about their tobacco use in nationally representative surveys among adults and adolescents.

Second-hand smoke is the smoke that fills restaurants, offices, homes, or other enclosed spaces when people smoke tobacco products. There is no safe level of exposure to second-hand tobacco smoke. Second-hand smoke causes serious cardiovascular and respiratory diseases, including coronary heart disease and lung cancer, and kills around 1.3 million people prematurely every year.

Hard-hitting anti-tobacco mass media campaigns and pictorial health warnings prevent children and other vulnerable groups from taking up tobacco use, and increase the number of tobacco users who quit.

Tobacco taxes are the most cost-effective way to reduce tobacco use, especially among youth and low-income groups. A tax increase that increases tobacco prices by 10% decreases tobacco consumption by about 4% in high-income countries and about 5% in low- and middle-income countries.

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