Whether sitting by a tranquil lake fishing or walking through the aisles of a pet store, seeing fish gracefully swimming raises the question: Can fish get drunk? Read on to find out the detailed answer.
If you’re short on time, here’s the quick answer: While fish don’t actively seek out alcohol, they can technically consume and be affected by it under very specific circumstances.
How Alcohol Affects Fish
Absorption of Alcohol
Fish absorb alcohol through their gills and skin when exposed to alcoholic solutions. The rate of absorption depends on factors like temperature, fish species, and alcohol concentration. Warm water speeds up absorption compared to cold water.
Alcohol is very soluble in water, allowing it to easily enter a fish’s bloodstream.
Once absorbed, alcohol spreads rapidly to tissues and organs in a fish’s body. Their livers break down and metabolize the ethanol, but fish livers are much smaller relative to body weight than human livers.
This means fish have a lower capacity to process alcohol, leading it to accumulate to higher internal concentrations.
Impacts on Behavior and Health
In excessive amounts, alcohol acts as a depressant on the central nervous system of fish, slowing reflexes, coordination, and swimming ability. Intoxicated fish may have trouble maintaining buoyancy, equilibrium, and orientation. They also become less responsive to external stimuli.
Long-term alcohol exposure threatens the welfare of fish. Chronic ethanol intake can damage gill tissues, suppress immune function, inhibit growth and reproduction, disrupt endocrine systems, and cause organ damage.
The toxicity level depends on the alcohol concentration, duration of exposure, and fish sensitivity. Some consequences can be lethal.
Research on alcoholic beverages mixed into aquarium water indicates even small amounts of 1-2% ethanol by volume can negatively impact zebrafish behavior. Higher proof liquor above 5% caused loss of balance, erratic swimming, and loss of reflexes.
Total system failure and mortality occurred at 16% ethanol concentration after 24 hours.
Alcohol in Fish Habitats
Pollution from Human Activities
Alcohol pollution in aquatic environments often comes from human activities like industrial waste discharge and sewage contamination. Ethanol and other alcohols can enter rivers, lakes, and oceans through stormwater runoff, carrying residues from alcoholic beverage production, food processing, and healthcare facilities.
A 2017 study analyzed alcohol pollution in the Danshui River in Taiwan. Results showed concerning levels of ethanol, methanol, and isopropanol contamination from nearby industrial zones. These alcohols can harm aquatic life by reducing oxygen levels and altering water acidity.
Sewage systems also unavoidably introduce alcoholic compounds into waterways. One investigation of European wastewater treatment plants found that effluent discharged into rivers contained median alcohol concentrations ranging from 11 to 33 milligrams per liter.
While not extremely high, this demonstrates yet another pathway for alcohol to enter fragile aquatic ecosystems.
Fermentation of Organic Matter
In addition to pollution sources, alcohol can naturally occur in water through the microbial fermentation of organic matter like fallen leaves. For example, research in a New Zealand stream detected seasonal spikes in ethanol levels up to 3 milligrams per liter during autumn leaf fall.
Fortunately, most fish can tolerate dilute alcohol better than humans. Zebrafish studies found no effects on larval development when exposed to alcohol concentrations below 1%. While fish likely avoid drinking high-proof alcoholic beverages that might wash into rivers or oceans, they seem equipped to handle trace levels of ethanol and methanol from natural processes in their aquatic homes.
Intentional Consumption by Humans
Adding Alcohol to Aquariums
Some fishkeepers may be tempted to add alcohol like wine or beer to aquarium water, thinking it could be fun to see drunk fish. However, this practice should be avoided as it can be harmful or even fatal to fish.
Alcohol is toxic to fish because their bodies are not equipped to process it. Fish lack the liver enzymes that break down alcohol. As a result, alcohol added to aquarium water is directly absorbed into their bloodstream and tissues.
Even small amounts of 1-2% alcohol can get fish intoxicated, impair their swimming and behavior, and eventually cause respiratory failure.
Certain types of alcohol like beer and wine also contain hops, grapes, and yeast which contaminate aquarium water. The sugars and carbs can spike ammonia levels while the alcohol itself physically damages fish gills. This compromises their breathing and makes them prone to deadly infections.
While the idea of drunk fish may seem funny at first, it is ultimately an irresponsible practice that causes fish undue stress and suffering. Aquarists have an ethical obligation to maintain healthy water conditions for the wellbeing of their fish.
Cooking Fish in Alcohol
Cooking fish in alcoholic beverages like wine, beer, vodka, and rum can infuse flavor and moisture when done properly. However, certain risks need to be considered.
Fish have delicate lean flesh that can dry out and toughen during cooking. Poaching fish in an alcohol-based broth maintains moisture while allowing the fish to gently absorb complementary flavors from the liquid. White wines nicely complement fish like halibut or cod.
Fuller-bodied red wines pair well with salmon or tuna.
However, take care not to overpower the natural mild flavor of the fish. Use subtle amounts of wine or diluted stocks rather than immersing fish directly in strong spirits which can make it taste too boozy. Simmer fish in broth mixtures gently so alcohol can cook off instead of being absorbed raw.
Marinating fish in acidic alcohols like wine or lemon juice for prolonged time can start “cooking” it via denaturation, making it mushy. Brief marinades for 15-30 minutes are safer. Baking or frying fish works better than grilling, as drizzling alcohol over an open flame can cause flare-ups.
In general, lean white fish and oily fish like salmon take well to alcohol-infused cooking. But fish like tilapia and catfish have little natural fat or oil to balance sharp alcoholic flavors. Milder cooking liquids work better.
With some care, cooking fish in moderate amounts of alcohol can add wonderful new dimensions of flavor.
Conclusion
While fish likely do not purposefully consume alcohol like humans, there are some very specific cases where fish can absorb and be physiologically impacted by alcohol compounds. However, these situations are quite rare in the wild.
The health impacts of alcohol on fish are generally negative, so intentionally exposing fish to alcohol, whether in aquariums or cooking, should be avoided.
In summary, under normal circumstances fish do not actively drink alcohol like humans. But they can technically absorb and experience effects from alcohol introduced into their water in cases of pollution or intentional exposure.
Overall fish did not evolve to consume alcohol recreationally, so intake is extremely limited compared to terrestrial species.