Garter snakes and some other small snakes inhabit similar environments in certain parts of North America, so it is possible for garter snakes to be found near ponds with Koi, Goldfish, or other fish you have in your pond.
Is it true that garter snakes eat goldfish or Koi?
Garter snakes are not a natural predator of goldfish or koi, but there have been reports that some garter snakes have been seen feeding on fish and other animals found in ponds where they live. It has also been reported that some garter snake species from North America even eat small mammals. This is unusual behavior and not normal for garter snakes.
Do fish ponds attract snakes?
Fish ponds can attract snakes because the water is warmer than the surrounding areas. Snakes are ectotherms (cold-blooded) and react to heat much like a human does: if the temperature is higher, they will be more active.
Garter snakes like other reptiles cannot tolerate cold temperatures, so in cooler climates, they look for areas to warm up by basking in the sun. Ponds and other water sources can sometimes attract snakes because of their proximity to food sources (that are not easy for them to catch).
What do garter snakes eat?
Garter snakes are not natural predators of goldfish and other fish. They normally eat amphibians, frogs, toads, mammals (including mice), birds, reptiles (such as lizards), and insects.
Goldfish in ponds have been reported to be one of the prey items for some species of garter snake, but it does not seem to be the predominant diet of any species. More garter snakes are seen eating frogs and other amphibians that live in or near the water than garter snakes eating fish.
Garter snakes also eat rodents and moles found near ponds where they live. They are sometimes even seen eating insects that fall into the water.
How can you keep garter snakes away?
Garter snakes are not aggressive and do not attack people or pets. They are shy animals, but if you find one in your garden or backyard, then there is no reason to panic because they will go away on their own.
The best way to get rid of them is to remove the reasons why they have come there in the first place.
Some of the things that attract garter snakes are Moist soil, water bodies (such as ponds), and hiding places like brush piles. Garter snakes do not build homes like some other species of snake, so if you eliminate these three factors from your property, then you will not attract garter snakes.
Garter snakes and other herpetological animals are interesting and they can provide us with a place to learn about the natural world, so there is no reason for anyone to kill garter snakes.
If you have concerns about them harming your pets or plants, then make sure that you take the steps to prevent them from coming near your property.
What do garter snakes eat in your garden/backyard?
Pond fish
Though it is not strictly the diet of any species, garter snakes are known to prey on fish in ponds. They seem to prefer amphibians over fish and other pond creatures like insects, crustaceans, and mollusks.
In addition to eating frogs and other amphibians found near water bodies, some species of garter snake have been reported to eat small mammals like mice, rats, and voles.
Tree frogs
In the wild, garter snakes sometimes prey on frogs. Tree frogs fall into that category, but not all species of tree frogs are a natural food source for garter snakes—though some animals’ diets can vary seasonally.
Garter snakes have been found to eat about anything living in or near their habitat; almost half of what they eat are amphibians, which include frogs and toads.
Tree frogs found around water bodies are both a food source for garter snakes and a predator of some of the tree frog species that live in or near those same water bodies.
The rest of their diets consist of insects, rodents, small mammals like mice and voles, and other reptiles.
Toads
Most garter snakes are toad eaters. They start out eating smaller amphibians while they are young; they also start with smaller amphibians that live close to the water.
Toads are usually the largest amphibians found near water bodies where garter snakes live, so they can be easy to catch and consume. Toads are also good prey but sometimes poisonous if their skin is touched; however, it doesn’t seem to harm garter snakes when they eat them.
Most species of small toads fall prey to garter snakes. The toad that is most susceptible to being eaten by a garter snake is called the American green frog.
While garter snakes are often not the first animals that come to mind when we consider predators of amphibians and reptiles, they do eat those animals when given the opportunity.
Lizards
While it is possible for them to prey on other reptiles like lizards, the majority of the time when a garter snake encounters a lizard, they will flee instead of attacking.
In some regions where there are abundant prey sources like frogs and toads, garter snakes mostly eat them. Keep in mind that these snakes can also be opportunistic eaters; this means that if they see mice or other small mammals near their habitat, then they may kill and eat those animals because they are easier to catch than frogs and toads.
Baby mice or rats
The majority of the time garter snakes will try to avoid eating larger prey, but during an infestation, nothing is off-limits. When faced with a population of rodents that have overrun their habitat, it seems like this type of snake will eat anything it can catch and consume.
Garter snakes do not usually eat larger prey, but when faced with a population of small rodents like rats and mice that have taken over their habitat, they will kill whatever they are able to catch.
Baby opossums
Garter snakes that live near water bodies are known to eat baby opossums.
While they may not seem like a natural food source, garter snakes can and do eat them. In fact, if you go near their habitat where there is abundant prey available like frogs and toads, then you might find one that has just consumed an opossum.
In Summary
It’s important to know that garter snakes are not always the top predator of the water bodies where they live. There are certain species that eat other animals, and some will even consume small mammals like mice and voles if those types of rodents have taken over their habitat.
Garter snakes don’t usually prey on fish from ponds, but there have been reports of this happening. Garter snakes are opportunistic eaters; that means that they will take advantage of any situation when it provides them with an easy meal like fish from a pond instead of frogs or toads.
Garter snakes can be found near water bodies all over North America, so if you live in an area with these reptiles, you should take safety precautions to ensure that they don’t try to get into your pond.
References:
Garter Snakes in and Around the Home https://wildlife.unl.edu/pdfs/garter-snakes-in-around-home.pdf
Common Garter Snake (Thamnophis sirtalis) https://tourism.oregonstate.edu/common-garter-snake-thamnophis-sirtalis/
